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Clinical engineering.
Clinical engineering is the branch of biomedical engineering dealing with the actual implementation of medical equipment and technologies in hospitals or other clinical settings. Major roles of clinical engineers include training and supervising biomedical equipment technicians (BMETs), selecting technological products/services and logistically managing their implementation, working with governmental regulators on inspections/audits, and serving as technological consultants for other hospital staff (e.g. physicians, administrators, I.T., etc.). Clinical engineers also advise and collaborate with medical device producers regarding prospective design improvements based on clinical experiences, as well as monitor the progression of the state of the art so as to redirect procurement patterns accordingly.
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Rehabilitation engineering.
Rehabilitation engineering is the systematic application of engineering sciences to design, develop, adapt, test, evaluate, apply, and distribute technological solutions to problems confronted by individuals with disabilities. Functional areas addressed through rehabilitation engineering may include mobility, communications, hearing, vision, and cognition, and activities associated with employment, independent living, education, and integration into the community.
While some rehabilitation engineers have master's degrees in rehabilitation engineering, usually a subspecialty of Biomedical engineering, most rehabilitation engineers have an undergraduate or graduate degrees in biomedical engineering, mechanical engineering, or electrical engineering. A Portuguese university provides an undergraduate degree and a master's degree in Rehabilitation Engineering and Accessibility. Qualification to become a Rehab' Engineer in the UK is possible via a University BSc Honours Degree course such as Health Design & Technology Institute, Coventry University.
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The rehabilitation process for people with disabilities often entails the design of assistive devices such as Walking aids intended to promote the inclusion of their users into the mainstream of society, commerce, and recreation.
Regulatory issues.
Regulatory issues have been constantly increased in the last decades to respond to the many incidents caused by devices to patients. For example, from 2008 to 2011, in US, there were 119 FDA recalls of medical devices classified as class I. According to U.S. Food and Drug Administration (FDA), Class I recall is associated to "a situation in which there is a reasonable probability that the use of, or exposure to, a product will cause serious adverse health consequences or death"
Regardless of the country-specific legislation, the main regulatory objectives coincide worldwide. For example, in the medical device regulations, a product must be: 1) safe "and" 2) effective and 3) for all the manufactured devices (why is this part deleted?)
A product is safe if patients, users, and third parties do not run unacceptable risks of physical hazards (death, injuries, ...) in its intended use. Protective measures have to be introduced on the devices to reduce residual risks at an acceptable level if compared with the benefit derived from the use of it.
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A product is effective if it performs as specified by the manufacturer in the intended use. Effectiveness is achieved through clinical evaluation, compliance to performance standards or demonstrations of substantial equivalence with an already marketed device.
The previous features have to be ensured for all the manufactured items of the medical device. This requires that a quality system shall be in place for all the relevant entities and processes that may impact safety and effectiveness over the whole medical device lifecycle.
The medical device engineering area is among the most heavily regulated fields of engineering, and practicing biomedical engineers must routinely consult and cooperate with regulatory law attorneys and other experts. The Food and Drug Administration (FDA) is the principal healthcare regulatory authority in the United States, having jurisdiction over medical "devices, drugs, biologics, and combination" products. The paramount objectives driving policy decisions by the FDA are safety and effectiveness of healthcare products that have to be assured through a quality system in place as specified under 21 CFR 829 regulation. In addition, because biomedical engineers often develop devices and technologies for "consumer" use, such as physical therapy devices (which are also "medical" devices), these may also be governed in some respects by the Consumer Product Safety Commission. The greatest hurdles tend to be 510K "clearance" (typically for Class 2 devices) or pre-market "approval" (typically for drugs and class 3 devices).
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In the European context, safety effectiveness and quality is ensured through the "Conformity Assessment" which is defined as "the method by which a manufacturer demonstrates that its device complies with the requirements of the European Medical Device Directive". The directive specifies different procedures according to the class of the device ranging from the simple Declaration of Conformity (Annex VII) for Class I devices to EC verification (Annex IV), Production quality assurance (Annex V), Product quality assurance (Annex VI) and Full quality assurance (Annex II). The Medical Device Directive specifies detailed procedures for Certification. In general terms, these procedures include tests and verifications that are to be contained in specific deliveries such as the risk management file, the technical file, and the quality system deliveries. The risk management file is the first deliverable that conditions the following design and manufacturing steps. The risk management stage shall drive the product so that product risks are reduced at an acceptable level with respect to the benefits expected for the patients for the use of the device. The technical file contains all the documentation data and records supporting medical device certification. FDA technical file has similar content although organized in a different structure. The Quality System deliverables usually include procedures that ensure quality throughout all product life cycles. The same standard (ISO EN 13485) is usually applied for quality management systems in the US and worldwide.
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In the European Union, there are certifying entities named "Notified Bodies", accredited by the European Member States. The Notified Bodies must ensure the effectiveness of the certification process for all medical devices apart from the class I devices where a declaration of conformity produced by the manufacturer is sufficient for marketing. Once a product has passed all the steps required by the Medical Device Directive, the device is entitled to bear a CE marking, indicating that the device is believed to be safe and effective when used as intended, and, therefore, it can be marketed within the European Union area.
The different regulatory arrangements sometimes result in particular technologies being developed first for either the U.S. or in Europe depending on the more favorable form of regulation. While nations often strive for substantive harmony to facilitate cross-national distribution, philosophical differences about the "optimal extent" of regulation can be a hindrance; more restrictive regulations seem appealing on an intuitive level, but critics decry the tradeoff cost in terms of slowing access to life-saving developments.
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RoHS II.
Directive 2011/65/EU, better known as RoHS 2 is a recast of legislation originally introduced in 2002. The original EU legislation "Restrictions of Certain Hazardous Substances in Electrical and Electronics Devices" (RoHS Directive 2002/95/EC) was replaced and superseded by 2011/65/EU published in July 2011 and commonly known as RoHS 2.
RoHS seeks to limit the dangerous substances in circulation in electronics products, in particular toxins and heavy metals, which are subsequently released into the environment when such devices are recycled.
The scope of RoHS 2 is widened to include products previously excluded, such as medical devices and industrial equipment. In addition, manufacturers are now obliged to provide conformity risk assessments and test reports – or explain why they are lacking. For the first time, not only manufacturers but also importers and distributors share a responsibility to ensure Electrical and Electronic Equipment within the scope of RoHS complies with the hazardous substances limits and have a CE mark on their products.
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IEC 60601.
The new International Standard IEC 60601 for home healthcare electro-medical devices defining the requirements for devices used in the home healthcare environment. IEC 60601-1-11 (2010) must now be incorporated into the design and verification of a wide range of home use and point of care medical devices along with other applicable standards in the IEC 60601 3rd edition series.
The mandatory date for implementation of the EN European version of the standard is June 1, 2013. The US FDA requires the use of the standard on June 30, 2013, while Health Canada recently extended the required date from June 2012 to April 2013. The North American agencies will only require these standards for new device submissions, while the EU will take the more severe approach of requiring all applicable devices being placed on the market to consider the home healthcare standard.
AS/NZS 3551:2012.
AS/ANS 3551:2012 is the Australian and New Zealand standards for the management of medical devices. The standard specifies the procedures required to maintain a wide range of medical assets in a clinical setting (e.g. Hospital). The standards are based on the IEC 606101 standards.
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The standard covers a wide range of medical equipment management elements including, procurement, acceptance testing, maintenance (electrical safety and preventive maintenance testing) and decommissioning.
Training and certification.
Education.
Biomedical engineers require considerable knowledge of both engineering and biology, and typically have a Bachelor's (B.Sc., B.S., B.Eng. or B.S.E.) or Master's (M.S., M.Sc., M.S.E., or M.Eng.) or a doctoral (Ph.D., or MD-PhD) degree in BME (Biomedical Engineering) or another branch of engineering with considerable potential for BME overlap. As interest in BME increases, many engineering colleges now have a Biomedical Engineering Department or Program, with offerings ranging from the undergraduate (B.Sc., B.S., B.Eng. or B.S.E.) to doctoral levels. Biomedical engineering has only recently been emerging as "its own discipline" rather than a cross-disciplinary hybrid specialization of other disciplines; and BME programs at all levels are becoming more widespread, including the Bachelor of Science in Biomedical Engineering which includes enough biological science content that many students use it as a "pre-med" major in preparation for medical school. The number of biomedical engineers is expected to rise as both a cause and effect of improvements in medical technology.
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In the U.S., an increasing number of undergraduate programs are also becoming recognized by ABET as accredited bioengineering/biomedical engineering programs. As of 2023, 155 programs are currently accredited by ABET.
In Canada and Australia, accredited graduate programs in biomedical engineering are common. For example, McMaster University offers an M.A.Sc, an MD/PhD, and a PhD in Biomedical engineering. The first Canadian undergraduate BME program was offered at University of Guelph as a four-year B.Eng. program. The Polytechnique in Montreal is also offering a bachelors's degree in biomedical engineering as is Flinders University.
As with many degrees, the reputation and ranking of a program may factor into the desirability of a degree holder for either employment or graduate admission. The reputation of many undergraduate degrees is also linked to the institution's graduate or research programs, which have some tangible factors for rating, such as research funding and volume, publications and citations. With BME specifically, the ranking of a university's hospital and medical school can also be a significant factor in the perceived prestige of its BME department/program.
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Graduate education is a particularly important aspect in BME. While many engineering fields (such as mechanical or electrical engineering) do not need graduate-level training to obtain an entry-level job in their field, the majority of BME positions do prefer or even require them. Since most BME-related professions involve scientific research, such as in pharmaceutical and medical device development, graduate education is almost a requirement (as undergraduate degrees typically do not involve sufficient research training and experience). This can be either a Masters or Doctoral level degree; while in certain specialties a Ph.D. is notably more common than in others, it is hardly ever the majority (except in academia). In fact, the perceived need for some kind of graduate credential is so strong that some undergraduate BME programs will actively discourage students from majoring in BME without an expressed intention to also obtain a master's degree or apply to medical school afterwards.
Graduate programs in BME, like in other scientific fields, are highly varied, and particular programs may emphasize certain aspects within the field. They may also feature extensive collaborative efforts with programs in other fields (such as the university's Medical School or other engineering divisions), owing again to the interdisciplinary nature of BME. M.S. and Ph.D. programs will typically require applicants to have an undergraduate degree in BME, or "another engineering" discipline (plus certain life science coursework), or "life science" (plus certain engineering coursework).
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Education in BME also varies greatly around the world. By virtue of its extensive biotechnology sector, its numerous major universities, and relatively few internal barriers, the U.S. has progressed a great deal in its development of BME education and training opportunities. Europe, which also has a large biotechnology sector and an impressive education system, has encountered trouble in creating uniform standards as the European community attempts to supplant some of the national jurisdictional barriers that still exist. Recently, initiatives such as BIOMEDEA have sprung up to develop BME-related education and professional standards. Other countries, such as Australia, are recognizing and moving to correct deficiencies in their BME education. Also, as high technology endeavors are usually marks of developed nations, some areas of the world are prone to slower development in education, including in BME.
Licensure/certification.
As with other learned professions, each state has certain (fairly similar) requirements for becoming licensed as a registered Professional Engineer (PE), but, in US, in industry such a license is not required to be an employee as an engineer in the majority of situations (due to an exception known as the industrial exemption, which effectively applies to the vast majority of American engineers). The US model has generally been only to require the practicing engineers offering engineering services that impact the public welfare, safety, safeguarding of life, health, or property to be licensed, while engineers working in private industry without a direct offering of engineering services to the public or other businesses, education, and government need not be licensed. This is notably not the case in many other countries, where a license is as legally necessary to practice engineering as it is for law or medicine.
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Biomedical engineering is regulated in some countries, such as Australia, but registration is typically only recommended and not required.
In the UK, mechanical engineers working in the areas of Medical Engineering, Bioengineering or Biomedical engineering can gain Chartered Engineer status through the Institution of Mechanical Engineers. The Institution also runs the Engineering in Medicine and Health Division. The Institute of Physics and Engineering in Medicine (IPEM) has a panel for the accreditation of MSc courses in Biomedical Engineering and Chartered Engineering status can also be sought through IPEM.
The Fundamentals of Engineering exam – the first (and more general) of two licensure examinations for most U.S. jurisdictions—does now cover biology (although technically not BME). For the second exam, called the Principles and Practices, Part 2, or the Professional Engineering exam, candidates may select a particular engineering discipline's content to be tested on; there is currently not an option for BME with this, meaning that any biomedical engineers seeking a license must prepare to take this examination in another category (which does not affect the actual license, since most jurisdictions do not recognize discipline specialties anyway). However, the Biomedical Engineering Society (BMES) is, as of 2009, exploring the possibility of seeking to implement a BME-specific version of this exam to facilitate biomedical engineers pursuing licensure.
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Beyond governmental registration, certain private-sector professional/industrial organizations also offer certifications with varying degrees of prominence. One such example is the Certified Clinical Engineer (CCE) certification for Clinical engineers.
Career prospects.
In 2012 there were about 19,400 biomedical engineers employed in the US, and the field was predicted to grow by 5% (faster than average) from 2012 to 2022. Biomedical engineering has the highest percentage of female engineers compared to other common engineering professions. Now as of 2023, there are 19,700 jobs for this degree, the average pay for a person in this field is around $100,730.00 and making around $48.43 an hour. There is also expected to be a 7% increase in jobs from here 2023 to 2033 (even faster than the last average). |
Balkans
The Balkans ( , ), corresponding partially with the Balkan Peninsula (Peninsula of Haemus, Haemaic Peninsula), is a geographical area in southeastern Europe with various geographical and historical definitions. The region takes its name from the Balkan Mountains (Haemus Mountains) that stretch throughout the whole of Bulgaria. The Balkan Peninsula is bordered by the Adriatic Sea in the northwest, the Ionian Sea in the southwest, the Aegean Sea in the south, the Turkish straits in the east, and the Black Sea in the northeast. The northern border of the peninsula is variously defined. The highest point of the Balkans is Musala, , in the Rila mountain range, Bulgaria.
The concept of the Balkan Peninsula was created by the German geographer August Zeune in 1808, who mistakenly considered the Balkan Mountains the dominant mountain system of Southeast Europe spanning from the Adriatic Sea to the Black Sea. In the 19th century the term "Balkan Peninsula" was a synonym for Rumelia, the parts of Europe that were provinces of the Ottoman Empire at the time. It had a geopolitical rather than a geographical definition, which was further promoted during the creation of the Kingdom of Yugoslavia in the early 20th century. The definition of the Balkan Peninsula's natural borders does not coincide with the technical definition of a peninsula; hence modern geographers reject the idea of a Balkan Peninsula, while historical scholars usually discuss the Balkans as a region. The term has acquired a stigmatized and pejorative meaning related to the process of Balkanization. The region may alternatively be referred to as Southeast Europe.
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The borders of the Balkans are, due to many contrasting definitions, widely disputed, with no universal agreement on its components. By most definitions, the term fully encompasses Albania, Bosnia and Herzegovina, Bulgaria, Croatia (up to the Sava and Kupa rivers), mainland Greece, Kosovo, Montenegro, North Macedonia, Northern Dobruja in Romania, Serbia (up to the Danube river) and European Turkey. However, many definitions also include the remaining territories of Croatia, Romania and Serbia, and southern parts of Slovenia. Additionally, some definitions include Hungary and Moldova due to cultural and historical affiliations. The Province of Trieste in northeastern Italy, whilst by some definitions on the geographical peninsula, is generally excluded from the Balkans in a regional context.
Name.
Etymology.
The origin of the word "Balkan" is obscure; it may be related to Turkish 'mud' (from Proto-Turkic *"bal" 'mud, clay; thick or gluey substance', cf. also Turkic 'honey'), and the Turkish suffix "-an" 'swampy forest' or Persian "bālā-khāna" 'big high house'. It was used mainly during the time of the Ottoman Empire. In both Ottoman Turkish and modern Turkish, "" means 'chain of wooded mountains'.
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Historical names and meaning.
Classical antiquity and the early Middle Ages.
From classical antiquity through the Middle Ages, the Balkan Mountains were called by the local Thracian name "Haemus". According to Greek mythology, the Thracian king Haemus was turned into a mountain by Zeus as a punishment and the mountain has remained with his name. A reverse name scheme has also been suggested. D. Dechev considers that Haemus (Αἷμος) is derived from a Thracian word "*saimon", 'mountain ridge'. A third possibility is that "Haemus" () derives from the Greek word "haima" () meaning 'blood'. The myth relates to a fight between Zeus and the monster/titan Typhon. Zeus injured Typhon with a thunder bolt and Typhon's blood fell on the mountains, giving them their name.
Late Middle Ages and Ottoman period.
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Evolution of meaning in the 19th and 20th centuries.
The term was not commonly used in geographical literature until the mid-19th century because, already then, scientists like Carl Ritter warned that only the part south of the Balkan Mountains could be considered as a peninsula and considered it to be renamed as "Greek peninsula". Other prominent geographers who did not agree with Zeune were Hermann Wagner, Theobald Fischer, Marion Newbigin, and Albrecht Penck, while Austrian diplomat Johann Georg von Hahn, in 1869, for the same territory, used the term "Südosteuropäische Halbinsel" ('Southeastern European peninsula'). Another reason it was not commonly accepted as the definition of then European Turkey had a similar land extent. However, after the Congress of Berlin (1878) there was a political need for a new term and gradually "the Balkans" was revitalized, but in many maps, the northern border was in Serbia and Montenegro and Greece was not included (it only depicted the then Ottoman-occupied parts of Europe), while Yugoslavian maps also included Croatia and Bosnia. At the time, the "Balkan Peninsula" was also understood as a synonym for Rumelia or "European Turkey", and, in its broadest sense, encompassed the borders of all former Ottoman provinces in Europe.
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The usage of the term changed in the very end of the 19th and beginning of the 20th century, when it was embraced by Serbian geographers, most prominently by Jovan Cvijić. It was done with political reasoning as affirmation for Serbian nationalism on the whole territory of the South Slavs, and also included anthropological and ethnological studies of the South Slavs through which were claimed various nationalistic and racialist theories. Through such policies and Yugoslavian maps the term was elevated to the modern status of a geographical region. The term acquired political nationalistic connotations far from its initial geographic meaning, arising from political changes from the late 19th century to the creation of post–World War I Yugoslavia (initially the Kingdom of Serbs, Croats and Slovenes in 1918). After the dissolution of Yugoslavia beginning in June 1991, the term "Balkans" acquired a negative political meaning, especially in Croatia and Slovenia, as well in worldwide casual usage for war conflicts and fragmentation of territory.
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Southeast Europe.
In part due to the historical and political connotations of the term "Balkans", especially since the military conflicts of the 1990s in Yugoslavia in the western half of the region, the term "Southeast Europe" is becoming increasingly popular. A European Union (EU) initiative of 1999 is called the "Stability Pact for Southeastern Europe".
The online newspaper "Balkan Times" renamed itself "Southeast European Times" in 2003.
Current.
In other languages of the Balkans, the region or peninsula are known as:
Definitions and boundaries.
Balkan Peninsula.
The Balkan Peninsula is bounded by the Adriatic Sea to the west, the Mediterranean Sea (including the Ionian and Aegean seas) and the Sea of Marmara to the south and the Black Sea to the east. Its northern boundary is subject to varying interpretations, but is often given as the Danube, Sava and Kupa Rivers. The Balkan Peninsula has a combined area of about . The peninsula is generally encompassed in the region known as Southeast Europe.
Italy currently holds a small area around Trieste that is by some older definitions considered a part of the Balkan Peninsula. However, the regions of Trieste and Istria are not usually considered part of the peninsula by Italian geographers, due to their definition limiting its western border to the Kupa River.
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Balkans.
The borders of the Balkans region are, due to a multitude contrasting definitions, widely disputed, with no universal agreement on its components. By most definitions, it fully encompasses Albania, Bosnia and Herzegovina, Bulgaria, Croatia (up to the Sava and Kupa rivers), mainland Greece, Kosovo, Montenegro, North Macedonia, Northern Dobruja in Romania, Serbia (up to the Danube river) and East Thrace in Turkey. However, many definitions also include the remaining territories of Croatia, Romania and Serbia, and southern parts of Slovenia. Additionally, some definitions include Hungary and Moldova due to cultural and historical affiliations. The Province of Trieste in northeastern Italy, whilst by some definitions on the geographical peninsula, is generally excluded from the Balkans in a regional context.
The term Southeast Europe may also be applied to the region, with various interpretations, although Balkan countries may alternatively be placed in Southern, Central or Eastern Europe. Turkey, including East Thrace, is generally placed in West Asia or the Middle East.
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Western Balkans.
The "Western Balkans" is a political neologism coined to refer to Albania and the territory of the former Yugoslavia, except Slovenia, since the early 1990s. The region of the Western Balkans, a coinage exclusively used in pan-European parlance, roughly corresponds to the Dinaric Alps territory.
The institutions of the EU have generally used the term "Western Balkans" to mean the Balkan area that includes countries that are not members of the EU, while others refer to the geographical aspects.
Each of these countries aims to be part of the future enlargement of the EU and reach democracy and transmission scores but, until then, they will be strongly connected with the pre-EU waiting programme Central European Free Trade Agreement. Croatia, considered part of the Western Balkans, joined the EU in July 2013.
Criticism as geographical definition.
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Croatian geographers and academics are highly critical of inclusion of Croatia within the broad geographical, social-political and historical context of the Balkans, while the neologism Western Balkans is perceived as a humiliation of Croatia by the European political powers. According to M. S. Altić, the term has two different meanings, "geographical, ultimately undefined, and cultural, extremely negative, and recently strongly motivated by the contemporary political context". In 2018, President of Croatia Kolinda Grabar-Kitarović stated that the use of the term "Western Balkans" should be avoided because it does not imply only a geographic area, but also negative connotations, and instead must be perceived as and called Southeast Europe because it is part of Europe.
Slovenian philosopher Slavoj Žižek said of the definition,
Nature and natural resources.
Most of the area is covered by mountain ranges running from the northwest to southeast. The main ranges are the Balkan Mountains (Stara Planina in Bulgarian language), running from the Black Sea coast in Bulgaria to the border with Serbia, the Rila-Rhodope massif in southern Bulgaria, the Dinaric Alps in Bosnia and Herzegovina, Croatia and Montenegro, the Korab-Šar mountains which spreads from Kosovo to Albania and North Macedonia, and the Pindus range, spanning from southern Albania into central Greece and the Albanian Alps, and the Alps at the northwestern border. The highest mountain of the region is Rila in Bulgaria, with Musala at 2,925 m, second being Mount Olympus in Greece, with Mytikas at 2,917 m, and Pirin mountain with Vihren, also in Bulgaria, being the third at 2915 m. The karst field or polje is a common feature of the landscape.
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On the Adriatic and Aegean coasts, the climate is Mediterranean, on the Black Sea coast the climate is humid subtropical and oceanic, and inland it is humid continental. In the northern part of the peninsula and on the mountains, winters are frosty and snowy, while summers are hot and dry. In the southern part, winters are milder. The humid continental climate is predominant in Bosnia and Herzegovina, northern Croatia, Bulgaria, Kosovo, northern Montenegro, the Republic of North Macedonia, and the interior of Albania and Serbia. Meanwhile, the other less common climates, the humid subtropical and oceanic climates, are seen on the Black Sea coast of Bulgaria and Balkan Turkey (European Turkey). The Mediterranean climate is seen on the Adriatic coasts of Albania, Croatia and Montenegro, as well as the Ionian coasts of Albania and Greece, in addition to the Aegean coasts of Greece and Balkan Turkey (European Turkey).
Over the centuries, forests have been cut down and replaced with bush. In the southern part and on the coast there is evergreen vegetation. Inland there are woods typical of Central Europe (oak and beech, and in the mountains, spruce, fir and pine). The tree line in the mountains lies at the height of 1,800–2,300 m. The land provides habitats for numerous endemic species, including extraordinarily abundant insects and reptiles that serve as food for a variety of birds of prey and rare vultures.
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The soils are generally poor, except on the plains, where areas with natural grass, fertile soils and warm summers provide an opportunity for tillage. Elsewhere, land cultivation is mostly unsuccessful because of the mountains, hot summers and poor soils, although certain cultures such as olive and grape flourish.
Resources of energy are scarce, except in Kosovo, where considerable coal, lead, zinc, chromium and silver deposits are located. Other deposits of coal, especially in Bulgaria, Serbia and Bosnia, also exist. Lignite deposits are widespread in Greece. Petroleum scarce reserves exist in Greece, Serbia and Albania. Natural gas deposits are scarce. Hydropower is in wide use, from over 1,000 dams. The often relentless bora wind is also being harnessed for power generation.
Metal ores are more usual than other raw materials. Iron ore is rare, but in some countries there is a considerable amount of copper, zinc, tin, chromite, manganese, magnesite and bauxite. Some metals are exported.
History and geopolitical significance.
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Antiquity.
The Balkan region was the first area in Europe to experience the arrival of farming cultures in the Neolithic era. The Balkans have been inhabited since the Paleolithic and are the route by which farming from the Middle East spread to Europe during the Neolithic (7th millennium BC). The practices of growing grain and raising livestock arrived in the Balkans from the Fertile Crescent by way of Anatolia and spread west and north into Central Europe, particularly through Pannonia. Two early culture-complexes have developed in the region, Starčevo culture and Vinča culture. The Balkans are also the location of the first advanced civilizations. Vinča culture developed a form of proto-writing before the Sumerians and Minoans, known as the Old European script, while the bulk of the symbols had been created in the period between 4500 and 4000 BC, with the ones on the Tărtăria clay tablets even dating back to around 5300 BC.
The identity of the Balkans is dominated by its geographical position; historically the area was known as a crossroads of cultures. It has been a juncture between the Latin and Greek bodies of the Roman Empire, the destination of a massive influx of pagan Bulgars and Slavs, an area where Orthodox and Catholic Christianity met, as well as the meeting point between Islam and Christianity.
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Albanic, Hellenic, and other Palaeo-Balkan languages, had their formative core in the Balkans after the Indo-European migrations in the region. In pre-classical and classical antiquity, this region was home to Greeks, Illyrians, Paeonians, Thracians, Dacians, and other ancient groups. The Achaemenid Persian Empire incorporated parts of the Balkans comprising Macedonia, Thrace (parts of present-day eastern Bulgaria), and the Black Sea coastal region of Romania beginning in 512 BC. Following the Persian defeat in the Greco-Persian Wars in 479 BC, they abandoned all of their European territories, which regained their independence. During the reign of Philip II of Macedon (359-336 BC), Macedonia rose to become the most powerful state in the Balkans. In the second century BC, the Roman Empire conquered the region and spread Roman culture and the Latin language, but significant parts still remained under classical Greek influence. The only Paleo-Balkan languages that survived are Albanian and Greek. The Romans considered the Rhodope Mountains to be the northern limit of the Peninsula of Haemus and the same limit applied approximately to the border between Greek and Latin use in the region (later called the Jireček Line). However large spaces south of Jireček Line were and are inhabited by Vlachs (Aromanians), the Romance-speaking heirs of Roman Empire.
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The Bulgars and Slavs arrived in the sixth-century and began assimilating and displacing already-assimilated (through Romanization and Hellenization) older inhabitants of the northern and central Balkans. This migration brought about the formation of distinct ethnic groups amongst the South Slavs, which included the Bulgarians, Croats and Serbs and Slovenes. Prior to the Slavic landing, parts of the western peninsula have been home to the Proto-Albanians. Including cities like Nish, Shtip, and Shkup. This can be proven through the development of the names, for example "Naissos" > "Nish" and "Astibos" > "Shtip" follow Albanian phonetic sound rules and have entered Slavic, indicating that Proto-Albanian was spoken prior to the Slavic invasion of the Balkans. Proto-Albanian speakers were Christianized under the Latin sphere of influence, specifically in the 4th century CE, as shown by the basic Christian terms in Albanian, which are of Latin origin and entered Proto-Albanian before the Gheg–Tosk dialectal diversification.
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Middle Ages and Early modern period.
During the Early Middle Ages, The Byzantine Empire was the dominant state in the region, both military and culturally. Their cultural strength became particularly evident in the second half of the 9th century when the Byzantine missionaries Cyril and Methodius managed to spread the Byzantine variant of Christianity to the majority of the Balkans inhabitants who were pagan beforehand. Initially, it was adopted by the Bulgarians and Serbs, with the Romanians joining a bit later. The lack of Old Church Slavonic terms in Albanian Christian terminology shows that the missionary activities during the Christianization of the Slavs did not involve Albanian-speakers, indeed, the Christian belief among Albanians had survived through the centuries and already become an important cultural element in their ethnic identity.
The emergence of the First Bulgarian Empire and the constant conflicts between the Byzantine Empire and the First Bulgarian Empire significantly weakened the Byzantine control over the Balkans by the end of the 10th century. The Byzantines further lost power in the Balkans after the resurgence of the Bulgarians in the late 12th century, with the forming of their Second Bulgarian Empire. After the collapse of the Second Bulgarian Empire, the Byzantine's Empire grip on power was prolonged by the inability of the Slavs to unite, which was caused by frequent infighting amongst themselves. Bulgaria in the first half of the 14th century was then overshadowed by the new rising regional power of Serbia, which was a result of Stefan Dušan rising up and conquering much of the Balkans to create the Serbian Empire. The Serbian and Byzantine empires continued to be the dominant forces in the region until the arrival of the Ottomans several decades later.
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Ottoman expansion in the region began in the second half of the 14th century, as the Byzantine Empire continued to lose its grip on the region after several defeats to the Ottomans. In 1362, the Ottoman Turks conquered Adrianople (now Edirne, Turkey). This was the start of their conquest of the Balkan Peninsula, which lasted for more than a century. Other states in the area starting falling like Serbia after the Siege of Smederevo in 1459, Bulgaria in 1396, Byzantine Empire in 1453, Bosnia in 1463, Herzegovina in 1482, and Montenegro in 1496. The conquest was made easier for the Ottomans due to existing divisions among the Orthodox peoples and by the even deeper rift that had existed at the time between the Eastern and Western Christians of Europe.
The Albanians under Skanderbeg's leadership resisted the Ottomans for a time (1443–1468) by using guerilla warfare. Skanderbeg's achievements, in particular the Battle of Albulena and the First Siege of Krujë won him fame across Europe. The Ottomans eventually conquered the near entirety of the Balkans and reached central Europe by the early 16th century. Some smaller countries, such as Montenegro managed to retain some autonomy by managing their own internal affairs, since the territory was too mountainous to completely subdue. Another small country that retained its independence, both de facto and de jure in this case, was the Adriatic trading hub of Ragusa (now Dubrovnik, Croatia).
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By the end of the 16th century, the Ottoman Empire had become the controlling force in the region after expanding from Anatolia through Thrace to the Balkans. Many people in the Balkans place their greatest folk heroes in the era of either the onslaught or the retreat of the Ottoman Empire. As examples, for Greeks, Constantine XI Palaiologos and Kolokotronis; and for Serbs, Miloš Obilić, Tsar Lazar and Karađorđe; for Albanians, George Kastrioti Skanderbeg; for ethnic Macedonians, Nikola Karev and Goce Delčev; for Bulgarians, Vasil Levski, Georgi Sava Rakovski and Hristo Botev and for Croats, Nikola Šubić Zrinjski.
In the past several centuries, because of the frequent Ottoman wars in Europe fought in and around the Balkans and the comparative Ottoman isolation from the mainstream of economic advance (reflecting the shift of Europe's commercial and political centre of gravity towards the Atlantic), the Balkans have been the least developed part of Europe. According to Halil İnalcık, "The population of the Balkans, according to one estimate, fell from a high of 8 million in the late 16th-century to only 3 million by the mid-eighteenth. This estimate is based on Ottoman documentary evidence".
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Most of the Balkan nation-states emerged during the 19th and early 20th centuries as they gained independence from the Ottoman or Habsburg empires: Greece in 1821, Serbia and Montenegro in 1878, Romania in 1881, Bulgaria in 1908 and Albania in 1912.
Recent history.
World wars.
In 1912–1913, the First Balkan War broke out when the nation-states of Bulgaria, Serbia, Greece and Montenegro united in an alliance against the Ottoman Empire. As a result of the war, almost all remaining European territories of the Ottoman Empire were captured and partitioned among the allies. Ensuing events also led to the creation of an independent Albanian state. Bulgaria insisted on its status quo territorial integrity, divided and shared by the Great Powers next to the Russo-Turkish War (1877–78) in other boundaries and on the pre-war Bulgarian-Serbian agreement. Bulgaria was provoked by the backstage deals between its former allies, Serbia and Greece, on the allocation of the spoils at the end of the First Balkan War. At the time, Bulgaria was fighting at the main Thracian Front. Bulgaria marks the beginning of Second Balkan War when it attacked them. The Serbs and the Greeks repulsed single attacks, but when the Greek army invaded Bulgaria together with an unprovoked Romanian intervention in the back, Bulgaria collapsed. The Ottoman Empire used the opportunity to recapture Eastern Thrace, establishing its new western borders that still stand today as part of modern Turkey.
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World War I was sparked in the Balkans in 1914 when members of Young Bosnia, a revolutionary organization with predominantly Serb and pro-Yugoslav members, assassinated the Austro-Hungarian heir Archduke Franz Ferdinand of Austria in Bosnia and Herzegovina's capital, Sarajevo. That caused a war between Austria-Hungary and Serbia, which—through the existing chains of alliances—led to the World War I. The Ottoman Empire soon joined the Central Powers becoming one of the three empires participating in that alliance. The next year Bulgaria joined the Central Powers attacking Serbia, which was successfully fighting Austria-Hungary to the north for a year. That led to Serbia's defeat and the intervention of the Entente in the Balkans which sent an expeditionary force to establish a new front, the third one of that war, which soon also became static. The participation of Greece in the war three years later, in 1918, on the part of the Entente finally altered the balance between the opponents leading to the collapse of the common German-Bulgarian front there, which caused the exit of Bulgaria from the war, and in turn, the end of World War I and the collapse of the Austro-Hungarian Empire.
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Between the two wars, in order to maintain the geopolitical status quo in the region after the end of World War I, the Balkan Pact, or Balkan Entente, was formed by a treaty between Greece, Romania, Turkey and Yugoslavia on 9 February 1934 in Athens.
With the start of the World War II, all Balkan countries, with the exception of Greece, were allies of Nazi Germany, having bilateral military agreements or being part of the Axis Pact. Fascist Italy expanded the war in the Balkans by using its protectorate Albania to invade Greece. After repelling the attack, the Greeks counterattacked, invading Italy-held Albania and causing Nazi Germany's intervention in the Balkans to help its ally. Days before the German invasion, a successful "coup d'état" in Belgrade by neutral military personnel seized power.
Although the new government reaffirmed its intentions to fulfill its obligations as a member of the Axis, Germany, with Bulgaria, invaded both Greece and Yugoslavia. Yugoslavia immediately disintegrated when those loyal to the Serbian King and the Croatian units mutinied. Greece resisted, but, after two months of fighting, collapsed and was occupied. The two countries were partitioned between the three Axis allies, Bulgaria, Germany and Italy, and the Independent State of Croatia, a puppet state of Italy and Germany.
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During the occupation, the population suffered considerable hardship due to repression and starvation, to which the population reacted by creating a mass resistance movement. Together with the early and extremely heavy winter of that year (which caused hundreds of thousands of deaths among the poorly fed population), the German invasion had disastrous effects in the timetable of the planned invasion in Russia causing a significant delay, which had major consequences during the course of the war.
Finally, at the end of 1944, the Soviets entered Romania and Bulgaria forcing the Germans out of the Balkans. They left behind a region largely ruined as a result of wartime exploitation.
Cold War.
During the Cold War, most of the countries on the Balkans were governed by communist governments. Greece became the first battleground of the emerging Cold War. The Truman Doctrine was the US response to the civil war, which raged from 1944 to 1949. This civil war, unleashed by the Communist Party of Greece, backed by communist volunteers from neighboring countries (Albania, Bulgaria and Yugoslavia), led to massive American assistance for the non-communist Greek government. With this backing, Greece managed to defeat the partisans and, ultimately, remained one of the two only non-communist countries in the region with Turkey.
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However, despite being under communist governments, Yugoslavia (1948) and Albania (1961) fell out with the Soviet Union. Yugoslavia, led by Marshal Josip Broz Tito (1892–1980), first propped up then rejected the idea of merging with Bulgaria and instead sought closer relations with the West, later even spearheaded, together with India and Egypt the Non-Aligned Movement. Albania on the other hand gravitated toward Communist China, later adopting an isolationist position.
On 28 February 1953, Greece, Turkey and Yugoslavia signed the treaty of Agreement of Friendship and Cooperation in Ankara to form the Balkan Pact of 1953. The treaty's aim was to deter Soviet expansion in the Balkans and eventual creation of a joint military staff for the three countries. When the pact was signed, Turkey and Greece were members of the NATO, while Yugoslavia was a non-aligned communist state. With the Pact, Yugoslavia was able to indirectly associate itself with NATO. Though it was planned for the pact to remain in force for 20 years, it dissolved in 1960.
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As the only non-communist countries, Greece and Turkey were (and still are) part of NATO composing the southeastern wing of the alliance.
Post–Cold War.
In the 1990s, the transition of the regions' ex-Eastern bloc countries towards democratic free-market societies went peacefully. While in the non-aligned Yugoslavia, Wars between the former Yugoslav republics broke out after Slovenia and Croatia held free elections and their people voted for independence on their respective countries' referendums. Serbia, in turn, declared the dissolution of the union as unconstitutional and the Yugoslav People's Army unsuccessfully tried to maintain the status quo. Slovenia and Croatia declared independence on 25 June 1991, which prompted the Croatian War of Independence in Croatia and the Ten-Day War in Slovenia. The Yugoslav forces eventually withdrew from Slovenia in 1991 while the war in Croatia continued until late 1995. The two were followed by Macedonia and later Bosnia and Herzegovina, with Bosnia being the most affected by the fighting. The wars prompted the United Nations' intervention and NATO ground and air forces took action against Serb forces in Bosnia and Herzegovina and FR Yugoslavia (i.e. Serbia and Montenegro).
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From the dissolution of Yugoslavia, six states achieved internationally recognized sovereignty: Slovenia, Croatia, Bosnia and Herzegovina, North Macedonia, Montenegro and Serbia; all of them are traditionally included in the Balkans which is often a controversial matter of dispute. In 2008, while under UN administration, Kosovo declared independence (according to the official Serbian policy, Kosovo is still an internal autonomous region). In July 2010, the International Court of Justice, ruled that the declaration of independence was legal. Most UN member states recognise Kosovo. After the end of the wars a revolution broke in Serbia and Slobodan Milošević, the Serbian communist leader (elected president between 1989 and 2000), was overthrown and handed for a trial to the International Criminal Tribunal for crimes against the International Humanitarian Law during the Yugoslav wars. Milošević died of a heart attack in 2006 before a verdict could have been released. Ιn 2001 an Albanian uprising in Macedonia (North Macedonia) forced the country to give local autonomy to the ethnic Albanians in the areas where they predominate.
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With the dissolution of Yugoslavia, an issue emerged over the name under which the former (federated) republic of Macedonia would internationally be recognized, between the new country and Greece. Being the Macedonian part of Yugoslavia (see Vardar Macedonia), the federated republic under the Yugoslav identity had the name (Socialist) Republic of Macedonia on which it declared its sovereignty in 1991. Greece, having a large homonymous region (see Macedonia), opposed the usage of the name as an indication of a nationality and ethnicity. Thus dubbed Macedonia naming dispute was resolved under UN mediation in the June 2018 Prespa agreement was reached, which saw the country's renaming into North Macedonia in 2019.
Balkan countries control the direct land routes between Western Europe and South-West Asia (Asia Minor and the Middle East). Since 2000, all Balkan countries are friendly towards the EU and the US.
Greece has been a member of the EU since 1981, while Slovenia is a member since 2004, Bulgaria and Romania are members since 2007, and Croatia is a member since 2013. In 2005, the EU decided to start accession negotiations with candidate countries; Turkey, and North Macedonia were accepted as candidates for EU membership. In 2012, Montenegro started accession negotiations with the EU. In 2014, Albania is an official candidate for accession to the EU. In 2015, Serbia was expected to start accession negotiations with the EU, however this process has been stalled over the recognition of Kosovo as an independent state by existing EU member states.
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Greece and Turkey have been NATO members since 1952. In March 2004, Bulgaria, Romania and Slovenia have become members of NATO. As of April 2009, Albania and Croatia are members of NATO. Montenegro joined in June 2017. The most recent member state to be added to NATO was North Macedonia on 27 March 2020.
Almost all other countries have expressed a desire to join the EU, NATO, or both at some point in the future.
Economy.
Currently, all of the states are republics, but until World War II all countries were monarchies. Most of the republics are parliamentary, excluding Romania and Bosnia which are semi-presidential. All the states have open market economies, most of which are in the upper-middle-income range ($4,000–12,000 p.c.), except Croatia, Romania, Greece, and Slovenia that have high income economies (over $12,000 p.c.), and are classified with very high HDI, along with Bulgaria, in contrast to the remaining states, which are classified with high HDI. The states from the former Eastern Bloc that formerly had planned economy system and Turkey mark gradual economic growth each year. The gross domestic product per capita is highest in Slovenia (over $29,000), followed by Croatia and Greece (~$20,000), Romania, Bulgaria (over $11,000), Turkey, Montenegro, Serbia (between $10,000 and $9,000), and Bosnia and Herzegovina, Albania, North Macedonia (~$7,000) and Kosovo ($5,000). The Gini coefficient, which indicates the level of difference by monetary welfare of the layers, is on the second level at the highest monetary equality in Albania, Bulgaria, and Serbia, on the third level in Greece, Montenegro and Romania, on the fourth level in North Macedonia, on the fifth level in Turkey, and the most unequal by Gini coefficient is Bosnia at the eighth level which is the penultimate level and one of the highest in the world. The unemployment is lowest in Romania and Bulgaria (around 5%), followed by Serbia and Albania (11–12%), Turkey, Greece, Bosnia, North Macedonia (13–16%), Montenegro (~18%), and Kosovo (~25%).
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As nations in the Western Balkans opened up to private investment in the 1990s, newly created enterprises (mostly SMEs) fueled regional economic development by facilitating the transition from a massive state-owned structure to a market economy. SMEs now account for 99% of all active businesses, up to 81% of total value created, and 72% of total employment in the Western Balkans.
The Western Balkans are mostly bank-based economies, with bank credit serving as the primary source of external capital for all enterprises, including SMEs. Despite this, the region's bank credit supply is limited and undeveloped. A recent analysis from the European Investment Bank estimated the funding deficit to be at US$2.8 billion, or around 2.5% of nominal GDP.
In most Western Balkan markets, international banks have a market share of 70% to 90%. At the end of 2023, the macroeconomic environment in the Western Balkans indicates that risks are increasing, threatening to worsen the financial imbalance. Recent survey findings give conflicting data on enterprises' funding circumstances. While supply has fallen as a result of the COVID-19 pandemic and interest rate increasers, it has showed progressive recovery.
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Regional organizations.
"See also the Black Sea regional organizations"
Demographics.
The region is inhabited by Albanians, Aromanians, Bulgarians, Bosniaks, Croats, Gorani, Greeks, Istro-Romanians, Macedonians, Hungarians, Megleno-Romanians, Montenegrins, Serbs, Slovenes, Romanians, Turks, and other ethnic groups which present minorities in certain countries like the Romani and Ashkali.
Religion.
The region is a meeting point of Orthodox Christianity, Islam and Roman Catholic Christianity. Eastern Orthodoxy is the majority religion in both the Balkan Peninsula and the Balkan region, The Eastern Orthodox Church has played a prominent role in the history and culture of Eastern and Southeastern Europe. A variety of different traditions of each faith are practiced, with each of the Eastern Orthodox countries having its own national church. A part of the population in the Balkans defines itself as irreligious.
Islam has a significant history in the region where Muslims make up a large percentage of the population. A 2013 estimate placed the total Muslim population of the Balkans at around eight million. Islam is the largest religion in nations like Albania, Bosnia-Herzegovina, and Kosovo with significant minorities in Bulgaria, North Macedonia and Montenegro. Smaller populations of Muslims are also found in Romania, Serbia and Greece.
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The Jewish communities of the Balkans were some of the oldest in Europe and date back to ancient times. These communities were Sephardi Jews, except in Croatia and Slovenia, where the Jewish communities were mainly Ashkenazi Jews. In Bosnia and Herzegovina, the small and close-knit Jewish community is 90% Sephardic, and Ladino is still spoken among the elderly. The Sephardi Jewish cemetery in Sarajevo has tombstones of a unique shape and inscribed in ancient Ladino. Sephardi Jews used to have a large presence in the city of Thessaloniki, and by 1900, some 80,000, or more than half of the population, were Jews. The Jewish communities in the Balkans suffered immensely during World War II, and the vast majority were killed during the Holocaust. An exception were the Bulgarian Jews who Boris III of Bulgaria sent to forced labor camps instead of Nazi concentration camps. Almost all of the few survivors have emigrated to the (then) newly founded state of Israel and elsewhere. Almost no Balkan country today has a significant Jewish minority.
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Languages.
The Balkan region today is a very diverse ethnolinguistic region, being home to multiple Slavic and Romance languages, as well as Albanian, Greek, Turkish, Hungarian and others. Romani is spoken by a large portion of the Romanis living throughout the Balkan countries. Throughout history, many other ethnic groups with their own languages lived in the area, among them Thracians, Illyrians, Romans, Celts and various Germanic tribes. All of the aforementioned languages from the present and from the past belong to the wider Indo-European language family, with the exception of the Turkic languages (e.g., Turkish and Gagauz) and Hungarian.
Urbanization.
Most of the states in the Balkans are predominantly urbanized, with the lowest number of urban population as % of the total population found in Bosnia and Herzegovina at 49%, Kosovo at 50% and Slovenia at 55%.
A list of largest cities:
Only the European part of Istanbul is a part of the Balkans. It is home to two-thirds of the city's 15,519,267 inhabitants.
Time zones.
The time zones in the Balkans are defined as the following: |
Bohr model
In atomic physics, the Bohr model or Rutherford–Bohr model was the first successful model of the atom. Developed from 1911 to 1918 by Niels Bohr and building on Ernest Rutherford's nuclear model, it supplanted the plum pudding model of J. J. Thomson only to be replaced by the quantum atomic model in the 1920s. It consists of a small, dense nucleus surrounded by orbiting electrons. It is analogous to the structure of the Solar System, but with attraction provided by electrostatic force rather than gravity, and with the electron energies quantized (assuming only discrete values).
In the history of atomic physics, it followed, and ultimately replaced, several earlier models, including Joseph Larmor's Solar System model (1897), Jean Perrin's model (1901), the cubical model (1902), Hantaro Nagaoka's Saturnian model (1904), the plum pudding model (1904), Arthur Haas's quantum model (1910), the Rutherford model (1911), and John William Nicholson's nuclear quantum model (1912). The improvement over the 1911 Rutherford model mainly concerned the new quantum mechanical interpretation introduced by Haas and Nicholson, but forsaking any attempt to explain radiation according to classical physics.
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The model's key success lies in explaining the Rydberg formula for hydrogen's spectral emission lines. While the Rydberg formula had been known experimentally, it did not gain a theoretical basis until the Bohr model was introduced. Not only did the Bohr model explain the reasons for the structure of the Rydberg formula, it also provided a justification for the fundamental physical constants that make up the formula's empirical results.
The Bohr model is a relatively primitive model of the hydrogen atom, compared to the valence shell model. As a theory, it can be derived as a first-order approximation of the hydrogen atom using the broader and much more accurate quantum mechanics and thus may be considered to be an obsolete scientific theory. However, because of its simplicity, and its correct results for selected systems (see below for application), the Bohr model is still commonly taught to introduce students to quantum mechanics or energy level diagrams before moving on to the more accurate, but more complex, valence shell atom. A related quantum model was proposed by Arthur Erich Haas in 1910 but was rejected until the 1911 Solvay Congress where it was thoroughly discussed. The quantum theory of the period between Planck's discovery of the quantum (1900) and the advent of a mature quantum mechanics (1925) is often referred to as the "old quantum theory".
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Background.
Until the second decade of the 20th century, atomic models were generally speculative. Even the concept of atoms, let alone atoms with internal structure, faced opposition from some scientists.
Planetary models.
In the late 1800s speculations on the possible structure of the atom included planetary models with orbiting charged electrons.
These models faced a significant constraint.
In 1897, Joseph Larmor showed that an accelerating charge would radiate power according to classical electrodynamics, a result known as the Larmor formula. Since electrons forced to remain in orbit are continuously accelerating, they would be mechanically unstable. Larmor noted that electromagnetic effect of multiple electrons, suitable arranged, would cancel each other. Thus subsequent atomic models based on classical electrodynamics needed to adopt such special multi-electron arrangements.
Thomson's atom model.
When Bohr began his work on a new atomic theory in the summer of 1912 the atomic model proposed by J. J. Thomson, now known as the plum pudding model, was the best available. Thomson proposed a model with electrons rotating in coplanar rings within an atomic-sized, positively-charged, spherical volume. Thomson showed that this model was mechanically stable by lengthy calculations and was electrodynamically stable under his original assumption of thousands of electrons per atom. Moreover, he suggested that the particularly stable configurations of electrons in rings was connected to chemical properties of the atoms. He developed a formula for the scattering of beta particles that seemed to match experimental results.
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However Thomson himself later showed that the atom had a factor of a thousand fewer electrons, challenging the stability argument and forcing the poorly understood positive sphere to have most of the atom's mass. Thomson was also unable to explain the many lines in atomic spectra.
Rutherford nuclear model.
In 1908, Hans Geiger and Ernest Marsden demonstrated that alpha particle occasionally scatter at large angles, a result inconsistent with Thomson's model.
In 1911 Ernest Rutherford developed a new scattering model, showing that the observed large angle scattering could be explained by a compact, highly charged mass at the center of the atom.
Rutherford scattering did not involve the electrons and thus his model of the atom was incomplete.
Bohr begins his first paper on his atomic model by describing Rutherford's atom as consisting of a small, dense, positively charged nucleus attracting negatively charged electrons.
Atomic spectra.
By the early twentieth century, it was expected that the atom would account for the many atomic spectral lines. These lines were summarized in empirical formula by Johann Balmer and Johannes Rydberg. In 1897, Lord Rayleigh showed that vibrations of electrical systems predicted spectral lines that depend on the square of the vibrational frequency, contradicting the empirical formula which depended directly on the frequency.
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In 1907 Arthur W. Conway showed that, rather than the entire atom vibrating, vibrations of only one of the electrons in the system described by Thomson might be sufficient to account for spectral series. Although Bohr's model would also rely on just the electron to explain the spectrum, he did not assume an electrodynamical model for the atom.
The other important advance in the understanding of atomic spectra was the Rydberg–Ritz combination principle which related atomic spectral line frequencies to differences between 'terms', special frequencies characteristic of each element. Bohr would recognize the terms as energy levels of the atom divided by the Planck constant, leading to the modern view that the spectral lines result from energy differences.
Haas atomic model.
In 1910, Arthur Erich Haas proposed a model of the hydrogen atom with an electron circulating on the surface of a sphere of positive charge. The model resembled Thomson's plum pudding model, but Haas added a radical new twist: he constrained the electron's potential energy, formula_1, on a sphere of radius to equal the frequency, , of the electron's orbit on the sphere times the Planck constant:
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formula_2
where represents the charge on the electron and the sphere. Haas combined this constraint with the balance-of-forces equation. The attractive force between the electron and the sphere balances the centrifugal force:
formula_3
where is the mass of the electron. This combination relates the radius of the sphere to the Planck constant:
formula_4
Haas solved for the Planck constant using the then-current value for the radius of the hydrogen atom.
Three years later, Bohr would use similar equations with different interpretation. Bohr took the Planck constant as given value and used the equations to predict, , the radius of the electron orbiting in the ground state of the hydrogen atom. This value is now called the Bohr radius.
Influence of the Solvay Conference.
The first Solvay Conference, in 1911, was one of the first international physics conferences. Nine Nobel or future Nobel laureates attended, including
Ernest Rutherford, Bohr's mentor.
Bohr did not attend but he read the Solvay reports and discussed them with Rutherford.
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The subject of the conference was the theory of radiation and the energy quanta of Max Planck's oscillators.
Planck's lecture at the conference ended with comments about atoms and the discussion that followed it concerned atomic models. Hendrik Lorentz raised the question of the composition of the atom based on Haas's model, a form of Thomson's plum pudding model with a quantum modification. Lorentz explained that the size of atoms could be taken to determine the Planck constant as Haas had done or the Planck constant could be taken as determining the size of atoms. Bohr would adopt the second path.
The discussions outlined the need for the quantum theory to be included in the atom. Planck explicitly mentions the failings of classical mechanics. While Bohr had already expressed a similar opinion in his PhD thesis, at Solvay the leading scientists of the day discussed a break with classical theories. Bohr's first paper on his atomic model cites the Solvay proceedings saying: "Whatever the alteration in the laws of motion of the electrons may be, it seems necessary to introduce in the laws in question a quantity foreign to the classical electrodynamics, "i.e." Planck's constant, or as it often is called the elementary quantum of action." Encouraged by the Solvay discussions, Bohr would assume the atom was stable and abandon the efforts to stabilize classical models of the atom
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Nicholson atom theory.
In 1911 John William Nicholson published a model of the atom which would influence Bohr's model. Nicholson developed his model based on the analysis of astrophysical spectroscopy. He connected the observed spectral line frequencies with the orbits of electrons in his atoms. The connection he adopted associated the atomic electron orbital angular momentum with the Planck constant.
Whereas Planck focused on a quantum of energy, Nicholson's angular momentum quantum relates to orbital frequency.
This new concept gave Planck constant an atomic meaning for the first time. In his 1913 paper Bohr cites Nicholson as finding quantized angular momentum important for the atom.
The other critical influence of Nicholson work was his detailed analysis of spectra. Before Nicholson's work Bohr thought the spectral data was not useful for understanding atoms. In comparing his work to Nicholson's, Bohr came to understand the spectral data and their value. When he then learned from a friend about Balmer's compact formula for the spectral line data, Bohr quickly realized his model would match it in detail.
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Nicholson's model was based on classical electrodynamics along the lines of J.J. Thomson's plum pudding model but his negative electrons orbiting a positive nucleus rather than circulating in a sphere. To avoid immediate collapse of this system he required that electrons come in pairs so the rotational acceleration of each electron was matched across the orbit. By 1913 Bohr had already shown, from the analysis of alpha particle energy loss, that hydrogen had only a single electron not a matched pair. Bohr's atomic model would abandon classical electrodynamics.
Nicholson's model of radiation was quantum but was attached to the orbits of the electrons. Bohr quantization would associate it with differences in energy levels of his model of hydrogen rather than the orbital frequency.
Bohr's previous work.
Bohr completed his PhD in 1911 with a thesis 'Studies on the Electron Theory of Metals', an application of the classical electron theory of Hendrik Lorentz. Bohr noted two deficits of the classical model. The first concerned the specific heat of metals which James Clerk Maxwell noted in 1875: every additional degree of freedom in a theory of metals, like subatomic electrons, cause more disagreement with experiment. The second, the classical theory could not explain magnetism.
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After his PhD, Bohr worked briefly in the lab of JJ Thomson before moving to Rutherford's lab in Manchester to study radioactivity. He arrived just after Rutherford completed his proposal of a compact nuclear core for atoms. Charles Galton Darwin, also at Manchester, had just completed an analysis of alpha particle energy loss in metals, concluding the electron collisions where the dominant cause of loss. Bohr showed in a subsequent paper that Darwin's results would improve by accounting for electron binding energy. Importantly this allowed Bohr to conclude that hydrogen atoms have a single electron.
Development.
Next, Bohr was told by his friend, Hans Hansen, that the Balmer series is calculated using the Balmer formula, an empirical equation discovered by Johann Balmer in 1885 that described wavelengths of some spectral lines of hydrogen. This was further generalized by Johannes Rydberg in 1888, resulting in what is now known as the Rydberg formula.
After this, Bohr declared, "everything became clear".
In 1913 Niels Bohr put forth three postulates to provide an electron model consistent with Rutherford's nuclear model:
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Other points are:
Bohr's condition, that the angular momentum be an integer multiple of formula_23, was later reinterpreted in 1924 by de Broglie as a standing wave condition: the electron is described by a wave and a whole number of wavelengths must fit along the circumference of the electron's orbit:
According to de Broglie's hypothesis, matter particles such as the electron behave as waves. The of an electron is
which implies that
or
where formula_28 is the angular momentum of the orbiting electron. Writing formula_29 for this angular momentum, the previous equation becomes
which is Bohr's second postulate.
Bohr described angular momentum of the electron orbit as formula_31 while de Broglie's wavelength of formula_32 described formula_11 divided by the electron momentum. In 1913, however, Bohr justified his rule by appealing to the correspondence principle, without providing any sort of wave interpretation. In 1913, the wave behavior of matter particles such as the electron was not suspected.
In 1925, a new kind of mechanics was proposed, quantum mechanics, in which Bohr's model of electrons traveling in quantized orbits was extended into a more accurate model of electron motion. The new theory was proposed by Werner Heisenberg. Another form of the same theory, wave mechanics, was discovered by the Austrian physicist Erwin Schrödinger independently, and by different reasoning. Schrödinger employed de Broglie's matter waves, but sought wave solutions of a three-dimensional wave equation describing electrons that were constrained to move about the nucleus of a hydrogen-like atom, by being trapped by the potential of the positive nuclear charge.
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Electron energy levels.
The Bohr model gives almost exact results only for a system where two charged points orbit each other at speeds much less than that of light. This not only involves one-electron systems such as the hydrogen atom, singly ionized helium, and doubly ionized lithium, but it includes positronium and Rydberg states of any atom where one electron is far away from everything else. It can be used for K-line X-ray transition calculations if other assumptions are added (see Moseley's law below). In high energy physics, it can be used to calculate the masses of heavy quark mesons.
Calculation of the orbits requires two assumptions.
Derivation.
In classical mechanics, if an electron is orbiting around an atom with period T, and if its coupling to the electromagnetic field is weak, so that the orbit doesn't decay very much in one cycle, it will emit electromagnetic radiation in a pattern repeating at every period, so that the Fourier transform of the pattern will only have frequencies which are multiples of 1/T.
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However, in quantum mechanics, the quantization of angular momentum leads to discrete energy levels of the orbits, and the emitted frequencies are quantized according to the energy differences between these levels. This discrete nature of energy levels introduces a fundamental departure from the classical radiation law, giving rise to distinct spectral lines in the emitted radiation.
Bohr assumes that the electron is circling the nucleus in an elliptical orbit obeying the rules of classical mechanics, but with no loss of radiation due to the Larmor formula.
Denoting the total energy as "E", the negative electron charge as "e", the positive nucleus charge as "K=Z|e|", the electron mass as "me", half the major axis of the ellipse as "a", he starts with these equations:
formula_38
formula_39
"E" is assumed to be negative, because a positive energy is required to unbind the electron from the nucleus and put it at rest at an infinite distance.
Eq. (1a) is obtained from equating the centripetal force to the Coulombian force acting between the nucleus and the electron, considering that formula_40 (where "T" is the average kinetic energy and "U" the average electrostatic potential), and that for Kepler's second law, the average separation between the electron and the nucleus is "a".
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Eq. (1b) is obtained from the same premises of eq. (1a) plus the virial theorem, stating that, for an elliptical orbit,
formula_41
Then Bohr assumes that formula_42 is an integer multiple of the energy of a quantum of light with half the frequency of the electron's revolution frequency, i.e.:
formula_43
From eq. (1a,1b,2), it descends:
formula_44
formula_45
formula_46
He further assumes that the orbit is circular, i.e. formula_47, and, denoting the angular momentum of the electron as "L", introduces the equation:
formula_48
Eq. (4) stems from the virial theorem, and from the classical mechanics relationships between the angular momentum, the kinetic energy and the frequency of revolution.
From eq. (1c,2,4), it stems:
formula_49
where:
formula_50
that is:
formula_51
This results states that the angular momentum of the electron is an integer multiple of the reduced Planck constant.
Substituting the expression for the velocity gives an equation for "r" in terms of "n":
so that the allowed orbit radius at any "n" is
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The smallest possible value of "r" in the hydrogen atom () is called the Bohr radius and is equal to:
The energy of the "n"-th level for any atom is determined by the radius and quantum number:
An electron in the lowest energy level of hydrogen () therefore has about 13.6 eV less energy than a motionless electron infinitely far from the nucleus. The next energy level () is −3.4 eV. The third (3) is −1.51 eV, and so on. For larger values of "n", these are also the binding energies of a highly excited atom with one electron in a large circular orbit around the rest of the atom. The hydrogen formula also coincides with the Wallis product.
The combination of natural constants in the energy formula is called the Rydberg energy ("R"E):
This expression is clarified by interpreting it in combinations that form more natural units:
Since this derivation is with the assumption that the nucleus is orbited by one electron, we can generalize this result by letting the nucleus have a charge , where "Z" is the atomic number. This will now give us energy levels for hydrogenic (hydrogen-like) atoms, which can serve as a rough order-of-magnitude approximation of the actual energy levels. So for nuclei with "Z" protons, the energy levels are (to a rough approximation):
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The actual energy levels cannot be solved analytically for more than one electron (see "n"-body problem) because the electrons are not only affected by the nucleus but also interact with each other via the Coulomb force.
When "Z" = 1/"α" (), the motion becomes highly relativistic, and "Z"2 cancels the "α"2 in "R"; the orbit energy begins to be comparable to rest energy. Sufficiently large nuclei, if they were stable, would reduce their charge by creating a bound electron from the vacuum, ejecting the positron to infinity. This is the theoretical phenomenon of electromagnetic charge screening which predicts a maximum nuclear charge. Emission of such positrons has been observed in the collisions of heavy ions to create temporary super-heavy nuclei.
The Bohr formula properly uses the reduced mass of electron and proton in all situations, instead of the mass of the electron,
However, these numbers are very nearly the same, due to the much larger mass of the proton, about 1836.1 times the mass of the electron, so that the reduced mass in the system is the mass of the electron multiplied by the constant 1836.1/(1+1836.1) = 0.99946. This fact was historically important in convincing Rutherford of the importance of Bohr's model, for it explained the fact that the frequencies of lines in the spectra for singly ionized helium do not differ from those of hydrogen by a factor of exactly 4, but rather by 4 times the ratio of the reduced mass for the hydrogen vs. the helium systems, which was much closer to the experimental ratio than exactly 4.
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For positronium, the formula uses the reduced mass also, but in this case, it is exactly the electron mass divided by 2. For any value of the radius, the electron and the positron are each moving at half the speed around their common center of mass, and each has only one fourth the kinetic energy. The total kinetic energy is half what it would be for a single electron moving around a heavy nucleus.
Rydberg formula.
Beginning in late 1860s, Johann Balmer and later Johannes Rydberg and Walther Ritz developed increasingly accurate empirical formula matching measured atomic spectral lines.
Critical for Bohr's later work, Rydberg expressed his formula in terms of wave-number, equivalent to frequency. These formula contained a constant, formula_63, now known the Rydberg constant and a pair of integers indexing the lines:
formula_64
Despite many attempts, no theory of the atom could reproduce these relatively simple formula.
In Bohr's theory describing the energies of transitions or quantum jumps between orbital energy levels is able to explain these formula. For the hydrogen atom Bohr starts with his derived formula for the energy released as a free electron moves into a stable circular orbit indexed by formula_65:
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formula_66
The energy difference between two such levels is then:
formula_67
Therefore, Bohr's theory gives the Rydberg formula and moreover the numerical value the Rydberg constant for hydrogen in terms of more fundamental constants of nature, including the electron's charge, the electron's mass, and the Planck constant:
formula_68
Since the energy of a photon is
these results can be expressed in terms of the wavelength of the photon given off:
Bohr's derivation of the Rydberg constant, as well as the concomitant agreement of Bohr's formula with experimentally observed spectral lines of the Lyman ( =1), Balmer ( =2), and Paschen ( =3) series, and successful theoretical prediction of other lines not yet observed, was one reason that his model was immediately accepted.
To apply to atoms with more than one electron, the Rydberg formula can be modified by replacing with or with where is constant representing a screening effect due to the inner-shell and other electrons (see Electron shell and the later discussion of the "Shell Model of the Atom" below). This was established empirically before Bohr presented his model.
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Shell model (heavier atoms).
Bohr's original three papers in 1913 described mainly the electron configuration in lighter elements. Bohr called his electron shells, "rings" in 1913. Atomic orbitals within shells did not exist at the time of his planetary model. Bohr explains in Part 3 of his famous 1913 paper that the maximum electrons in a shell is eight, writing: "We see, further, that a ring of "n" electrons cannot rotate in a single ring round a nucleus of charge "ne" unless "n" < 8." For smaller atoms, the electron shells would be filled as follows: "rings of electrons will only join together if they contain equal numbers of electrons; and that accordingly the numbers of electrons on inner rings will only be 2, 4, 8". However, in larger atoms the innermost shell would contain eight electrons, "on the other hand, the periodic system of the elements strongly suggests that already in neon "N" = 10 an inner ring of eight electrons will occur". Bohr wrote "From the above we are led to the following possible scheme for the arrangement of the electrons in light atoms:"
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In Bohr's third 1913 paper Part III called "Systems Containing Several Nuclei", he says that two atoms form molecules on a symmetrical plane and he reverts to describing hydrogen. The 1913 Bohr model did not discuss higher elements in detail and John William Nicholson was one of the first to prove in 1914 that it couldn't work for lithium, but was an attractive theory for hydrogen and ionized helium.
In 1921, following the work of chemists and others involved in work on the periodic table, Bohr extended the model of hydrogen to give an approximate model for heavier atoms. This gave a physical picture that reproduced many known atomic properties for the first time although these properties were proposed contemporarily with the identical work of chemist Charles Rugeley Bury
Bohr's partner in research during 1914 to 1916 was Walther Kossel who corrected Bohr's work to show that electrons interacted through the outer rings, and Kossel called the rings: "shells". Irving Langmuir is credited with the first viable arrangement of electrons in shells with only two in the first shell and going up to eight in the next according to the octet rule of 1904, although Kossel had already predicted a maximum of eight per shell in 1916. Heavier atoms have more protons in the nucleus, and more electrons to cancel the charge. Bohr took from these chemists the idea that each discrete orbit could only hold a certain number of electrons. Per Kossel, after that the orbit is full, the next level would have to be used. This gives the atom a shell structure designed by Kossel, Langmuir, and Bury, in which each shell corresponds to a Bohr orbit.
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This model is even more approximate than the model of hydrogen, because it treats the electrons in each shell as non-interacting. But the repulsions of electrons are taken into account somewhat by the phenomenon of screening. The electrons in outer orbits do not only orbit the nucleus, but they also move around the inner electrons, so the effective charge Z that they feel is reduced by the number of the electrons in the inner orbit.
For example, the lithium atom has two electrons in the lowest 1s orbit, and these orbit at "Z" = 2. Each one sees the nuclear charge of "Z" = 3 minus the screening effect of the other, which crudely reduces the nuclear charge by 1 unit. This means that the innermost electrons orbit at approximately 1/2 the Bohr radius. The outermost electron in lithium orbits at roughly the Bohr radius, since the two inner electrons reduce the nuclear charge by 2. This outer electron should be at nearly one Bohr radius from the nucleus. Because the electrons strongly repel each other, the effective charge description is very approximate; the effective charge "Z" doesn't usually come out to be an integer.
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The shell model was able to qualitatively explain many of the mysterious properties of atoms which became codified in the late 19th century in the periodic table of the elements. One property was the size of atoms, which could be determined approximately by measuring the viscosity of gases and density of pure crystalline solids. Atoms tend to get smaller toward the right in the periodic table, and become much larger at the next line of the table. Atoms to the right of the table tend to gain electrons, while atoms to the left tend to lose them. Every element on the last column of the table is chemically inert (noble gas).
In the shell model, this phenomenon is explained by shell-filling. Successive atoms become smaller because they are filling orbits of the same size, until the orbit is full, at which point the next atom in the table has a loosely bound outer electron, causing it to expand. The first Bohr orbit is filled when it has two electrons, which explains why helium is inert. The second orbit allows eight electrons, and when it is full the atom is neon, again inert. The third orbital contains eight again, except that in the more correct Sommerfeld treatment (reproduced in modern quantum mechanics) there are extra "d" electrons. The third orbit may hold an extra 10 d electrons, but these positions are not filled until a few more orbitals from the next level are filled (filling the n=3 d orbitals produces the 10 transition elements). The irregular filling pattern is an effect of interactions between electrons, which are not taken into account in either the Bohr or Sommerfeld models and which are difficult to calculate even in the modern treatment.
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Moseley's law and calculation (K-alpha X-ray emission lines).
Niels Bohr said in 1962: "You see actually the Rutherford work was not taken seriously. We cannot understand today, but it was not taken seriously at all. There was no mention of it any place. The great change came from Moseley."
In 1913, Henry Moseley found an empirical relationship between the strongest X-ray line emitted by atoms under electron bombardment (then known as the K-alpha line), and their atomic number . Moseley's empiric formula was found to be derivable from Rydberg's formula and later Bohr's formula (Moseley actually mentions only Ernest Rutherford and Antonius Van den Broek in terms of models as these had been published before Moseley's work and Moseley's 1913 paper was published the same month as the first Bohr model paper). The two additional assumptions that [1] this X-ray line came from a transition between energy levels with quantum numbers 1 and 2, and [2], that the atomic number when used in the formula for atoms heavier than hydrogen, should be diminished by 1, to .
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Moseley wrote to Bohr, puzzled about his results, but Bohr was not able to help. At that time, he thought that the postulated innermost "K" shell of electrons should have at least four electrons, not the two which would have neatly explained the result. So Moseley published his results without a theoretical explanation.
It was Walther Kossel in 1914 and in 1916 who explained that in the periodic table new elements would be created as electrons were added to the outer shell. In Kossel's paper, he writes: "This leads to the conclusion that the electrons, which are added further, should be put into concentric rings or shells, on each of which ... only a certain number of electrons—namely, eight in our case—should be arranged. As soon as one ring or shell is completed, a new one has to be started for the next element; the number of electrons, which are most easily accessible, and lie at the outermost periphery, increases again from element to element and, therefore, in the formation of each new shell the chemical periodicity is repeated." Later, chemist Langmuir realized that the effect was caused by charge screening, with an inner shell containing only 2 electrons. In his 1919 paper, Irving Langmuir postulated the existence of "cells" which could each only contain two electrons each, and these were arranged in "equidistant layers".
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In the Moseley experiment, one of the innermost electrons in the atom is knocked out, leaving a vacancy in the lowest Bohr orbit, which contains a single remaining electron. This vacancy is then filled by an electron from the next orbit, which has n=2. But the n=2 electrons see an effective charge of "Z" − 1, which is the value appropriate for the charge of the nucleus, when a single electron remains in the lowest Bohr orbit to screen the nuclear charge +"Z", and lower it by −1 (due to the electron's negative charge screening the nuclear positive charge). The energy gained by an electron dropping from the second shell to the first gives Moseley's law for K-alpha lines,
or
Here, R"v = R"E/"h" is the Rydberg constant, in terms of frequency equal to 3.28 x 1015 Hz. For values of Z between 11 and 31 this latter relationship had been empirically derived by Moseley, in a simple (linear) plot of the square root of X-ray frequency against atomic number (however, for silver, Z = 47, the experimentally obtained screening term should be replaced by 0.4). Notwithstanding its restricted validity, Moseley's law not only established the objective meaning of atomic number, but as Bohr noted, it also did more than the Rydberg derivation to establish the validity of the Rutherford/Van den Broek/Bohr nuclear model of the atom, with atomic number (place on the periodic table) standing for whole units of nuclear charge. Van den Broek had published his model in January 1913 showing the periodic table was arranged according to charge while Bohr's atomic model was not published until July 1913.
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The K-alpha line of Moseley's time is now known to be a pair of close lines, written as (Kα1 and Kα2) in Siegbahn notation.
Shortcomings.
The Bohr model gives an incorrect value for the ground state orbital angular momentum: The angular momentum in the true ground state is known to be zero from experiment. Although mental pictures fail somewhat at these levels of scale, an electron in the lowest modern "orbital" with no orbital momentum, may be thought of as not to revolve "around" the nucleus at all, but merely to go tightly around it in an ellipse with zero area (this may be pictured as "back and forth", without striking or interacting with the nucleus). This is only reproduced in a more sophisticated semiclassical treatment like Sommerfeld's. Still, even the most sophisticated semiclassical model fails to explain the fact that the lowest energy state is spherically symmetric – it doesn't point in any particular direction.
In modern quantum mechanics, the electron in hydrogen is a spherical cloud of probability that grows denser near the nucleus. The rate-constant of probability-decay in hydrogen is equal to the inverse of the Bohr radius, but since Bohr worked with circular orbits, not zero area ellipses, the fact that these two numbers exactly agree is considered a "coincidence". (However, many such coincidental agreements are found between the semiclassical vs. full quantum mechanical treatment of the atom; these include identical energy levels in the hydrogen atom and the derivation of a fine-structure constant, which arises from the relativistic Bohr–Sommerfeld model (see below) and which happens to be equal to an entirely different concept, in full modern quantum mechanics).
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The Bohr model also failed to explain:
Refinements.
Several enhancements to the Bohr model were proposed, most notably the Sommerfeld or Bohr–Sommerfeld models, which suggested that electrons travel in elliptical orbits around a nucleus instead of the Bohr model's circular orbits. This model supplemented the quantized angular momentum condition of the Bohr model with an additional radial quantization condition, the Wilson–Sommerfeld quantization condition
where "pr" is the radial momentum canonically conjugate to the coordinate "qr", which is the radial position, and "T" is one full orbital period. The integral is the action of action-angle coordinates. This condition, suggested by the correspondence principle, is the only one possible, since the quantum numbers are adiabatic invariants.
The Bohr–Sommerfeld model was fundamentally inconsistent and led to many paradoxes. The magnetic quantum number measured the tilt of the orbital plane relative to the "xy" plane, and it could only take a few discrete values. This contradicted the obvious fact that an atom could have any orientation relative to the coordinates, without restriction. The Sommerfeld quantization can be performed in different canonical coordinates and sometimes gives different answers. The incorporation of radiation corrections was difficult, because it required finding action-angle coordinates for a combined radiation/atom system, which is difficult when the radiation is allowed to escape. The whole theory did not extend to non-integrable motions, which meant that many systems could not be treated even in principle. In the end, the model was replaced by the modern quantum-mechanical treatment of the hydrogen atom, which was first given by Wolfgang Pauli in 1925, using Heisenberg's matrix mechanics. The current picture of the hydrogen atom is based on the atomic orbitals of wave mechanics, which Erwin Schrödinger developed in 1926.
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However, this is not to say that the Bohr–Sommerfeld model was without its successes. Calculations based on the Bohr–Sommerfeld model were able to accurately explain a number of more complex atomic spectral effects. For example, up to first-order perturbations, the Bohr model and quantum mechanics make the same predictions for the spectral line splitting in the Stark effect. At higher-order perturbations, however, the Bohr model and quantum mechanics differ, and measurements of the Stark effect under high field strengths helped confirm the correctness of quantum mechanics over the Bohr model. The prevailing theory behind this difference lies in the shapes of the orbitals of the electrons, which vary according to the energy state of the electron.
The Bohr–Sommerfeld quantization conditions lead to questions in modern mathematics. Consistent semiclassical quantization condition requires a certain type of structure on the phase space, which places topological limitations on the types of symplectic manifolds which can be quantized. In particular, the symplectic form should be the curvature form of a connection of a Hermitian line bundle, which is called a prequantization.
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Bohr also updated his model in 1922, assuming that certain numbers of electrons (for example, 2, 8, and 18) correspond to stable "closed shells".
Model of the chemical bond.
Niels Bohr proposed a model of the atom and a model of the chemical bond. According to his model for a diatomic molecule, the electrons of the atoms of the molecule form a rotating ring whose plane is perpendicular to the axis of the molecule and equidistant from the atomic nuclei. The dynamic equilibrium of the molecular system is achieved through the balance of forces between the forces of attraction of nuclei to the plane of the ring of electrons and the forces of mutual repulsion of the nuclei. The Bohr model of the chemical bond took into account the Coulomb repulsion – the electrons in the ring are at the maximum distance from each other.
Symbolism of planetary atomic models.
Although Bohr's atomic model was superseded by quantum models in the 1920s, the visual image of electrons orbiting a nucleus has remained the popular concept of atoms.
The concept of an atom as a tiny planetary system has been widely used as a symbol for atoms and even for "atomic" energy (even though this is more properly considered nuclear energy). Examples of its use over the past century include but are not limited to: |
Bombay Sapphire
Bombay Sapphire is a brand of gin that is distilled by the Bombay Spirits Company, a subsidiary company of Bacardi, at Laverstoke Mill in the village of Laverstoke in the English county of Hampshire.
The brand was first launched in 1986 by English wine-merchant International Distillers & Vintners. In 1997 Diageo sold the brand to Bacardi. Its name originates from the gin and tonic popularised by the Royal Indian Armed Forces during the British Raj in colonial India; "Bombay" refers to the Indian city and "Sapphire" refers to the violet-blue Star of Bombay which was mined from British Ceylon (Sri Lanka), and is now on display at the Smithsonian Institution. Bombay Sapphire is marketed in a flat-sided, sapphire-coloured bottle that bears a picture of Queen Victoria on the label.
The flavouring of the drink comes from a recipe of ten ingredients: almond, lemon peel, liquorice, juniper berries, orris root, angelica, coriander, cassia, cubeb, and grains of paradise. Alcohol brought in from another supplier is evaporated three times using a carterhead still, and the alcohol vapours are passed through a mesh/basket containing the ten botanicals to gain flavour and aroma. This is felt to give the gin a lighter, more floral taste compared to gins created using a copper pot still. Water from Lake Vyrnwy, a reservoir in Powys, Wales is added to bring the strength of Bombay Sapphire down to 40.0% (UK, the Nordics, several continental European markets, Canada and Australia).
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The 47.0% version is the standard for sale at duty-free shops in all markets.
Production.
Until 2013, production and bottling of Bombay Sapphire was contracted out by Bacardi to G&J Greenall in Warrington, Cheshire. However, in 2011, plans were announced to move the manufacturing process to a new facility at Laverstoke Mill in Laverstoke, Hampshire. These plans included the restoration of the former Portal's paper mill at the proposed site and the construction of a visitor centre.
Planning permission was granted in February 2012, and the centre opened to the public in the autumn of 2014. The visitor centre included a new construction by Thomas Heatherwick of two glasshouses for plants used as botanicals in the production of Bombay Sapphire gin. As part of the transfer of production, two of Greenall's stills were moved from Warrington to Laverstoke.
After production was shifted to Laverstoke, bottling of the drink remained contracted out by G&J Greenall, with the undiluted gin being tankered to Warrington for dilution and bottling. Bottling has subsequently been shifted to Glasgow in Scotland.
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Varieties.
Bacardi also markets Bombay Original London Dry Gin (or Bombay Original Dry). Eight botanical ingredients are used in the production of the Original Dry variety, as opposed to the ten in Bombay Sapphire. "Wine Enthusiast" preferred it to Bombay Sapphire.
In September 2011, Bombay Sapphire East was launched in test markets in New York and Las Vegas. This variety has another two botanicals, lemongrass and black peppercorns, in addition to the original ten. It is bottled at 42% and was designed to counteract the sweetness of most tonic water.
A special edition of Bombay gin called Star of Bombay was produced in 2015 for the UK market. It is bottled at 47.5% and is distilled from grain. It features bergamot and ambrette seeds in harmony with Bombay's signature botanicals. This version has later been extended to several other markets.
Bombay Bramble is a variety infused with blackberries and raspberries and bottled at 37.5% ABV.
In the summer of 2019, Bacardi launched a limited edition gin called Bombay Sapphire English Estate, which features three additional English-sourced botanicals: Pennyroyal Mint, rosehip and hazelnut. It is bottled at 41%.
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Design connection.
The brand started a series of design collaborations. Their first step into the design world was a series of advertisements featuring work from currently popular designers. Their works, varying from martini glasses to tiles and cloth patterns, are labelled as "Inspired by Bombay Sapphire". The campaign featured designers such as Marcel Wanders, Yves Béhar, Karim Rashid, Ulla Darni, and Dror Benshetrit and performance artist Jurgen Hahn.
From the success of this campaign, the company began a series of events and sponsored locations. The best known is the Bombay Sapphire Designer Glass Competition, held each year, where design students worldwide can participate by designing their own "inspired" martini cocktail glass. The finalists (one from each participating country) are then invited to the yearly Salone del Mobile, an international design fair in Milan, where the winner is chosen.
Bombay Sapphire also endorses glass artists and designers with the Bombay Sapphire Prize, which is awarded yearly to an outstanding design featuring glass. Bombay Sapphire also showcases the designers' work in the Bombay Sapphire endorsed blue room, a design exhibition touring the world each year.
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From 2008 the Bombay Sapphire Designer Glass Competition final will be held at 100% Design in London, and the Bombay Sapphire Prize will take place in Milan at the Salone del Mobile.
Evaluation.
Bombay Sapphire has been reviewed by several outside spirits ratings organisations to various degrees of success. Recently, it was awarded a score of 92 (on a 100-point scale) from the Beverage Testing Institute. Ratings aggregator Proof66.com categorizes the Sapphire as a Tier 2 spirit, indicating highly favourable "expert" reviews. |
Bob Wills
James Robert "Bob" Wills (March 6, 1905 – May 13, 1975) was an American musician, songwriter, and bandleader. Considered by music authorities as the founder of Western swing, he was known widely as the King of Western Swing (although Spade Cooley self-promoted the moniker "King of Western Swing" from 1942 to 1969). He was also noted for punctuating his music with his trademark "ah-haa" calls.
Wills formed several bands and played radio stations around the South and West until he formed the Texas Playboys in 1934 with Wills on fiddle, Tommy Duncan on piano and vocals, rhythm guitarist June Whalin, tenor banjoist Johnnie Lee Wills, and Kermit Whalin who played steel guitar and bass. Oklahoma guitar player Eldon Shamblin joined the band in 1937 bringing jazzy influence and arrangements. The band played regularly on Tulsa, Oklahoma, radio station KVOO and added Leon McAuliffe on steel guitar, pianist Al Stricklin, drummer Smokey Dacus, and a horn section that expanded the band's sound. Wills favored jazz-like arrangements and the band found national popularity into the 1940s with such hits as "Steel Guitar Rag", "San Antonio Rose", "Smoke on the Water", "Stars and Stripes on Iwo Jima", and "New Spanish Two Step".
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Wills and the Texas Playboys recorded with several publishers and companies, including Vocalion, Okeh, Columbia, and MGM. In 1950, Wills had two top 10 hits, "Ida Red likes the Boogie" and "Faded Love", which were his last hits for a decade. Throughout the 1950s, he struggled with poor health and tenuous finances. He continued to perform frequently despite a decline in the popularity of his earlier hit songs, and the growing popularity of rock and roll. Wills had a heart attack in 1962, and a second one the next year, which forced him to disband the Texas Playboys. Wills continued to perform solo.
The Country Music Hall of Fame inducted Wills in 1968 and the Texas State Legislature honored him for his contribution to American music. In 1972, Wills accepted a citation from the American Society of Composers, Authors and Publishers in Nashville. He recorded an album with fan Merle Haggard in 1973. Wills suffered two strokes that left him partially paralyzed, and unable to communicate. He was comatose the last two months of his life, and died in a Fort Worth nursing home from pneumonia in 1975. The Rock and Roll Hall of Fame inducted Wills and the Texas Playboys in 1999.
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Biography.
Early years.
He was born on a cotton farm in Kosse, Texas, to Emma Lee Foley and John Tompkins Wills. His parents were both of primarily English ancestry, but had distant Irish ancestry, as well. The entire Wills family was musically inclined. His father was a statewide champion fiddle player, and several of his siblings played musical instruments. The family frequently held country dances in their home, and while living in Hall County, Texas, they also played at "ranch dances", which were popular throughout West Texas. In this environment, Wills learned to play the fiddle and the mandolin early.
Wills not only learned traditional music from his family, but he also learned some blues songs directly from African-American families who worked in the cotton fields near Lakeview, Texas. As a child, he mainly interacted with African-American children, learning their musical styles and dances such as jigs. Aside from his own family, he knew few other White children until he was seven or eight years old.
New Mexico and Texas.
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The family moved to Hall County in the Texas Panhandle in 1913, and in 1919 they bought a farm between the towns of Lakeview, Texas, and Turkey, Texas. At the age of 16, Wills left the family and hopped a freight train, travelling under the name Jim Rob. He drifted from town to town trying to earn a living for several years, once nearly falling from a moving train.
In his 20s, he attended barber school, married his first wife Edna, and moved first to Roy, New Mexico, then returned to Turkey in Hall County (now considered his home town) to work as a barber at Ham's Barber Shop. He alternated barbering and fiddling, even when he moved to Fort Worth, Texas, after leaving Hall County in 1929. There, he played in minstrel and medicine shows, and, as with other Texas musicians such as Ocie Stockard, continued to earn money as a barber. He wore blackface makeup to appear in comedy routines, something that was common at the time. Wills played the violin and sang, and had two guitarists and a banjo player with him. "Bob was in blackface and was the comic; he cracked jokes, sang, and did an amazing jig dance."
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Since there was already a Jim on the show, the manager began calling him Bob. As Jim Rob Wills, though, paired with Herman Arnspiger, he made his first commercial (though unissued) recordings in November 1929 for Brunswick/Vocalion. Wills quickly became known for being talkative on the bandstand, a tendency he picked up from family, local cowboys, and the style of Black musicians he had heard growing up.
While in Fort Worth, Wills added the "rowdy city blues" of Bessie Smith and Emmett Miller, whom he idolized, to a repertoire of mainly waltzes and breakdowns he had learned from his father, and patterned his vocal style after that of Miller and other performers such as Al Bernard. His 1935 version of "St. Louis Blues" replicates Al Bernard's patter from the 1928 version of the song. He described his love of Bessie Smith's music with an anecdote: "I rode horseback from the place between the rivers to Childress to see Bessie Smith... She was about the greatest thing I had ever heard. In fact, there was no doubt about it. She was the greatest thing I ever heard."
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In Fort Worth, Wills met Herman Arnspiger and formed the Wills Fiddle Band. In 1930, Milton Brown joined the group as lead vocalist and brought a sense of innovation and experimentation to the band, which became known as the Aladdin Laddies and then soon renamed itself the Light Crust Doughboys because of radio sponsorship by the makers of Light Crust Flour. Brown left the band in 1932 to form the Musical Brownies, the first true Western swing band. Brown added twin fiddles, tenor banjo, and slap bass, pointing the music in the direction of swing, which they played on local radio and at dancehalls.
The Texas Playboys.
After forming a new band, The Playboys, and relocating to Waco, Texas, Wills found enough popularity there to decide on a bigger market. They left Waco in January 1934 for Oklahoma City. Wills soon settled the renamed Texas Playboys in Tulsa, Oklahoma, and began broadcasting noon shows over the 50,000-watt KVOO radio station, from the stage of Cain's Ballroom. They also played dances in the evenings. Wills largely sang blues and sentimental ballads. "One Star Rag", "Rat Cheese Under the Hill", "Take Me Back to Tulsa", "Basin Street Blues", "Steel Guitar Rag", and "Trouble in Mind" were some of the songs in the extensive repertory played by Wills and the Playboys.
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Wills added a trumpet to the band inadvertently when he hired Everet Stover as an announcer, not knowing that he had played with the New Orleans symphony and had directed the governor's band in Austin. Stover, thinking he had been hired as a trumpeter, began playing with the band, and Wills never stopped him. Although Wills initially disapproved of it, young saxophonist Zeb McNally was eventually hired. Wills hired the young, "modern-style musician" Smoky Dacus as a drummer to balance out the horns.
He continued to expand the lineup through the mid- to late 1930s. The addition of steel guitar whiz Leon McAuliffe in March 1935 added not only a formidable instrumentalist, but also a second engaging vocalist. Wills and the Texas Playboys did their first recordings on September 23–25, 1935, in Dallas. Session rosters from 1938 show both lead guitar and electric guitar in addition to guitar and steel guitar in the Texas Playboys recordings. About this time, Wills purchased and performed with an antique Guadagnini violin. The instrument, worth an estimated $7,600 at the time, was purchased for only $1,600. In 1940, "New San Antonio Rose" sold a million records and became the signature song of the Texas Playboys. The "front line" of Wills' orchestra consisted of either fiddles or guitars after 1944.
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Film career.
In 1940, Wills, along with the Texas Playboys, co-starred with Tex Ritter in "Take Me Back to Oklahoma". Altogether, Wills appeared in 19 films, including "The Lone Prairie" (1942), "Riders of the Northwest Mounted" (1943), "Saddles and Sagebrush" (1943), "The Vigilantes Ride" (1943), "The Last Horseman" (1944), "Rhythm Round-Up" (1945), "Blazing the Western Trail" (1945), and "Lawless Empire" (1945).
Swing era.
In December 1942, after several band members had left the group, and as World War II raged, Wills joined the Army at the age of 37, but received a medical discharge in 1943. After leaving the Army, Wills moved to Hollywood and began to reorganize the Texas Playboys. He became an enormous draw in Los Angeles, where many of his fans had relocated during the Great Depression and World War II in search of jobs. Monday through Friday, the band played the noon hour timeslot over KMTR-AM (now KLAC) in Los Angeles. They also played regularly at the Mission Beach Ballroom in San Diego.
He commanded enormous fees playing dances there, and began to make more creative use of electric guitars to replace the big horn sections the Tulsa band had boasted. For a very brief period in 1944, the Wills band included 23 members, and around mid-year, he toured Northern California and the Pacific Northwest with 21 pieces in the orchestra. "Billboard" reported that Wills out-grossed Harry James, Benny Goodman, "both Dorsey brothers bands, et al." at Civic Auditorium in Oakland, California, in January 1944.
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Wills and His Texas Playboys began their first cross-country tour in November 1944, and appeared at the Grand Ole Opry on December 30, 1944. According to Opry policy, drums and horns were considered pop instruments, inappropriate to country music. The Opry had two Western swing bands on its roster, led by Pee Wee King and Paul Howard. Neither was allowed to use their drummers at the Opry. Wills' band at the time consisted of two fiddlers, two bass fiddles, two electric guitars, electric steel guitar, and a trumpet. Wills's then-drummer was Monte Mountjoy, who played in the Dixieland style. Wills battled Opry officials and refused to perform without his drummer. An attempt to compromise by keeping Mountjoy behind a curtain collapsed when Wills had his drums placed front and center onstage at the last minute.
In 1945, Wills' dances were drawing larger crowds than dances put on by Tommy Dorsey and Benny Goodman. That year, he lived in both Santa Monica and Fresno, California. In 1947, he opened the Wills Point nightclub in Sacramento, California, and continued touring the Southwest and Pacific Northwest from Texas to Washington. In Sacramento, he broadcast shows over KFBK, a station whose reach encompassed much of the American West. Wills was in such high demand that venues would book him even on weeknights, because they knew the show would still be a draw.
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During the postwar period, KGO radio in San Francisco syndicated a Bob Wills and His Texas Playboys show recorded at the Fairmont Hotel. Many of these recordings survive today as the Tiffany Transcriptions and are available on CD. They show off the band's strengths significantly, in part because the group was not confined to the three-minute limits of 78 RPM discs. On April 3, 1948, Wills and the Texas Playboys appeared for the inaugural broadcast of the "Louisiana Hayride" on KWKH, broadcasting from the Municipal Auditorium in Shreveport, Louisiana.
Wills and the Texas Playboys played dances throughout the West to more than 10,000 people every week. They held dance attendance records at Jantzen Beach in Portland, Oregon; Santa Monica, California; Klamath Falls, Oregon; and California's Oakland Auditorium, where they drew 19,000 people over two nights. Wills recalled the early days of what became known as Western swing music in a 1949 interview: "Here's the way I figure it. We sure not tryin' to take credit for swingin' it."
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Still a binge drinker, Wills became increasingly unreliable in the late 1940s, causing a rift with Tommy Duncan (who bore the brunt of audience anger when Wills's binges prevented him from appearing). It ended when he fired Duncan in the fall of 1948.
Later years.
Having lived a lavish lifestyle in California, Wills moved back to Oklahoma City in 1949, then went back on the road to maintain his payroll and Wills Point. He opened a second club, the Bob Wills Ranch House, in Dallas, Texas. Turning the club over to managers, later revealed to be dishonest, left Wills in desperate financial straits with heavy debts to the IRS for back taxes. This caused him to sell many assets, including the rights to "New San Antonio Rose".
In 1950, Wills had two top-10 hits, "Ida Red Likes the Boogie" and "Faded Love". After 1950, radio stations began to increasingly specialize in one form or another of commercially popular music. Although usually labelled "country and western", Wills did not fit into the style played on popular country and western stations, which typically played music in the Nashville sound. Neither did he fit into the conventional sound of pop stations, although he played a good deal of pop music.
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Wills continued to appear at the Bostonia Ballroom in San Diego throughout the 1950s. He continued to tour and record through the 1950s into the early 1960s despite the fact that Western swing's popularity, even in the Southwest, had greatly diminished. Charles R. Townsend described his drop in popularity: Bob could draw "a thousand people on Monday night between 1950 and 1952, but he could not do that by 1956. Entertainment habits had changed."
On Wills' return to Tulsa late in 1957, Jim Downing of the "Tulsa Tribune" wrote an article headlined "Wills Brothers Together Again: Bob Back with Heavy Beat". The article quotes Wills as saying "Rock and roll? Why, man, that's the same kind of music we've been playin' since 1928! ... We didn't call it rock and roll back when we introduced it as our style back in 1928, and we don't call it rock and roll the way we play it now. But it's just basic rhythm and has gone by a lot of different names in my time. It's the same, whether you just follow a drum beat like in Africa or surround it with a lot of instruments. The rhythm's what's important." The use of amplified guitars accentuates Wills's claim; some Bob Wills recordings from the 1930s and 1940s sound similar to rock and roll records of the 1950s.
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Even a 1958 return to KVOO, where his younger brother Johnnie Lee Wills had maintained the family's presence, did not produce the success he hoped. He appeared twice on ABC-TV's "Jubilee USA" and kept the band on the road into the 1960s. After two heart attacks, in 1965, he dissolved the Texas Playboys (who briefly continued as an independent unit) to perform solo with house bands. While he did well in Las Vegas and other areas, and made records for the Kapp Records label, he was largely a forgotten figure—even though inducted into the Country Music Hall of Fame in 1968. A 1969 stroke left his right side paralyzed, ending his active career. He did, however, recover sufficiently to appear in a wheelchair at various Wills tributes held in the early 1970s. A revival of interest in his music, spurred by Merle Haggard's 1970 album "A Tribute to the Best Damn Fiddle Player in the World", led to a 1973 reunion album, teaming Wills, who spoke with difficulty, with key members of the early band, as well as Haggard.
Wills died in Fort Worth of pneumonia on May 13, 1975.
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Personal life.
Bob Wills was married six times and divorced five times. He was twice married to, and twice divorced from, Mary Helen Brown, the widow of Wills' ex-band member Milton Brown.
Legacy.
Wills' style influenced performers Buck Owens, Merle Haggard, and The Strangers and helped to spawn a style of music now known as the Bakersfield Sound. (Bakersfield, California, was one of Wills' regular stops in his heyday). A 1970 tribute album by Haggard, "A Tribute to the Best Damn Fiddle Player in the World (or, My Salute to Bob Wills)" directed a wider audience to Wills's music, as did the appearance of younger "revival" bands like Asleep at the Wheel and Commander Cody and His Lost Planet Airmen plus the growing popularity of longtime Wills disciple and fan Willie Nelson. By 1971, Wills recovered sufficiently to travel occasionally and appear at tribute concerts. In 1973, he participated in a final reunion session with members of some of the Texas Playboys from the 1930s to the 1960s. Merle Haggard was invited to play at this reunion. The session, scheduled for two days, took place in December 1973, with the album to be titled "For the Last Time". Wills, speaking or attempting to holler, appeared on a couple tracks from the first day's session but suffered a stroke overnight. He had a more severe one a few days later. The musicians completed the album without him. Wills by then was comatose. He lingered until his death on May 13, 1975.
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Reviewing "For the Last Time" in "" (1981), Robert Christgau wrote: "This double-LP doesn't represent the band at its peak. But though earlier recordings of most of these classic tunes are at least marginally sharper, it certainly captures the relaxed, playful, eclectic Western swing groove that Wills invited in the '30s."
In addition to being inducted into the Country Music Hall of Fame in 1968, Wills was inducted into the Nashville Songwriters Hall of Fame in 1970, the Rock and Roll Hall of Fame in the Early Influence category along with the Texas Playboys in 1999, and received the Grammy Lifetime Achievement Award in 2007.
From 1974 until his 2002 death, Waylon Jennings performed a song he had written called "Bob Wills Is Still the King". Released as the B-side of a single that was a double-sided hit, it went to number one on the country charts. The song has become a staple of classic country radio station formats. In addition, The Rolling Stones performed this song live in Austin, Texas, at Zilker Park on their A Bigger Bang Tour, a shout-out to Wills. This performance was included on their subsequent DVD "The Biggest Bang". In a 1968 issue of "Guitar Player", rock guitarist Jimi Hendrix said of Wills and the Playboys: "I dig them. The Grand Ole Opry used to come on, and I used to watch that. They used to have some pretty heavy cats, some heavy guitar players." In fact, Bob Wills and His Texas Playboys only performed on the Opry twice: in 1944 and 1948. Hendrix almost surely referred to Nashville guitarists.
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Wills ranked number 27 in "CMT's 40 Greatest Men in Country Music" in 2003.
Wills' upbeat 1938 song "Ida Red" was Chuck Berry's primary inspiration for creating his first rock-and-roll hit "Maybellene".
Fats Domino once remarked that he patterned his 1960 rhythm section after that of Bob Wills.
During the 49th Grammy Awards in 2007, Carrie Underwood performed his song "San Antonio Rose". Today, George Strait performs Wills' music on concert tours and records songs influenced by Wills and his Texas-style swing.
The Austin-based Western swing band Asleep at the Wheel has honored Wills' music since the band's inception, mostly notably with their continuing performances of the musical drama "", which debuted in Austin in March 2005 to coincide with celebrations of Wills' 100th birthday.
The Bob Wills Birthday Celebration is held every year in March at the Cain's Ballroom in Tulsa, Oklahoma, with a Western swing concert and dance.
In 2004, a documentary film about his life and music, titled "Fiddlin' Man: The Life and Music of Bob Wills", was released by VIEW Inc.
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In 2011, Proper Records released an album by Hot Club of Cowtown titled "What Makes Bob Holler: A Tribute to Bob Wills and His Texas Playboys" and the Texas Legislature adopted a resolution designating Western swing as the official State Music of Texas.
The Greenville Chamber of Commerce hosts an annual Bob Wills Fiddle Festival and Contest in downtown Greenville, Texas, in November.
Bob Wills was honored in episode two of Ken Burns' 2019 series on PBS called "Country Music".
In 2021, Wills was inducted into the Texas Cowboy Hall of Fame. |
Badtrans
BadTrans is a malicious Microsoft Windows computer worm distributed by e-mail. Because of a known vulnerability in older versions of Internet Explorer (CVE-2001-0154), some email programs, such as Microsoft's Outlook Express and Microsoft Outlook programs, may install and execute the worm as soon as the e-mail message is viewed.
Once executed, the worm replicates by sending copies of itself to other e-mail addresses found on the host's machine, and installs a keystroke logger, which then captures everything typed on the affected computer. Badtrans then transmits the data to one of several e-mail addresses.
Among the e-mail addresses that received the keyloggers were free addresses at Excite, Yahoo, and IJustGotFired.com.
The target address at IJustGotFired began receiving emails at 3:23pm on November 24, 2001. Once the account exceeded its quotas, it was automatically disabled, but the messages were still saved as they arrived. The address received over 100,000 keylogs in the first day alone.
In mid-December, the FBI contacted Rudy Rucker, Jr., owner of MonkeyBrains, and requested a copy of the keylogged data. All of that data was stolen from the victims of the worm; it includes no information about the creator of Badtrans.
Instead of complying with the FBI request, MonkeyBrains published a database website, https://web.archive.org/web/20070621140432/https://badtrans.monkeybrains.net/ for the public to determine if a given address has been compromised. The database does not reveal the actual passwords or keylogged data. |
Barış Manço
Mehmet Barış Manço (born Tosun Yusuf Mehmet Barış Manço; 2 January 1943 – 1 February 1999), better known by his stage name Barış Manço, was a Turkish rock musician, singer, composer, actor, television producer and show host. Beginning his musical career while attending Galatasaray High School, he was a pioneer of rock music in Turkey and one of the founders of the Anatolian rock genre. Manço composed around 200 songs and is among the best-selling Turkish artists to date and the winner of the most awards. Many of his songs were translated into other languages including English, French, Japanese, Greek, Italian, Bulgarian, Romanian, Persian, Hebrew, Urdu, Arabic, and German. Through his TV programme, "7'den 77'ye" ("From 7 to 77"), Manço travelled the world and visited many countries. He remains one of Turkey's most popular public figures long after his death.
Early life and career.
Barış Manço was born in Üsküdar, Istanbul, Turkey on 2 January 1943. Born in Adana, his mother Rikkat Uyanık, was a famous singer in the early 1940s. His older brother, who was born during World War II, was named Savaş ("War" in Turkish) while he was named Barış ("Peace" in Turkish) by his parents to celebrate the end of the war. At birth, he was additionally named Tosun Yusuf after his deceased uncle Yusuf nicknamed Tosun (literally: Joseph the Sturdy). However, this name was erased just before he attended primary school.
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During his time at Galatasaray High School (and later in Şişli Terakki High School) in the 1950s he formed his first band, Kafadarlar (The Buddies), allegedly after seeing Erkin Koray's band - all students at the nearby Deutsche Schule Istanbul ("İstanbul Alman Lisesi") - performing. Prof. Dr. Asaf Savaş Akat, a famous economist in Turkey, played saxophone, while guitarist Ender Enön made his own guitar because it was difficult to find a real one on the market in those years.
In 1962 and 1963, with his next band, Harmoniler (The Harmonies), he recorded cover versions of some popular American twist songs and rearrangements of Turkish folk songs in rock and roll form, thus marking the beginning of the Anatolian rock movement, a synthesis of Turkish folk music and rock. In this period, his key visual and musical influence was Elvis Presley.
After graduating from high school in 1963, he moved to Europe, traveling to Paris and Liège where he formed bands with local musicians and recorded some singles mainly in English and French but also in Turkish. Then, in 1964, he resumed his studies at the Royal Academy of Fine Arts in Liège, Belgium. He toured with his band Les Mistigris (not related to Mistigris) in Germany, Belgium, France and Turkey until 1967.
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In 1967, he suffered a serious car accident, after which he started to grow his signature moustache to conceal his scar.
Frustrated by the difficulties of working with musicians from different nationalities, he formed Kaygısızlar (The Carefrees), featuring Mazhar Alanson and Fuat Güner, future members of the band MFÖ. He recorded several singles and toured with the band, both domestically and internationally, until the band members protested that they did not want to live abroad.
In 1970, he formed Barış Manço Ve... (Barış Manço and...) again with foreign musicians, to record his first hit single, "Dağlar Dağlar" (Mountains, Mountains!), which was a success in both Turkey and Belgium, selling over 700,000 copies. It remains one of his most popular songs.
1970s.
After the success of "Dağlar Dağlar", Manço recorded a couple of singles with Moğollar (The Mongols), another influential Turkish Anatolian rock band. He then decided to return to Turkey where he recorded with the reformed Kaygısızlar for a short period. In 1971, his early works were compiled under his first full-length album "Dünden Bugüne ("From Yesterday to Today")", today commonly referred to as "Dağlar Dağlar".
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In 1972, he formed the legendary Kurtalan Ekspres that would accompany him until his death. While continuing to release singles, in 1975 he also released his first non-compilation LP "2023", a concept album that included many instrumental pieces.
In a last attempt to achieve international success, he released an LP simply entitled "Baris Mancho" (1976), a strange transcription of his name. It was mostly completed with the George Hayes Orchestra on the CBS Records label in Europe and South Africa. Although the album did not bring him the fame he was hoping for, it did top the charts in Romania and Morocco. The following year, the album was released in Turkey under the title "Nick the Chopper". In 1975 he starred in the movie "Baba Bizi Eversene" (Father Make Us Marry), the only movie he starred in during his career. Its music is a compilation of tracks composed by Barış Manço and Kurtalan Ekspres.
From 1977 to 1980, he released three more albums in Turkey, partly consisting of compilations of older singles, namely "Sakla Samanı Gelir Zamanı" (1977), "Yeni Bir Gün" (A New Day, 1979) and "20. Sanat Yılı Disko Manço" (1980), all following a similar sound to "2023". All these albums are now rarities, but most of the material is available in later compilations "Ben Bilirim" and "Sarı Çizmeli Mehmet Ağa".
1980s.
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