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Melons are monoecious or andromonoecious plants. They do not cross with watermelon, cucumber, pumpkin, or squash, but varieties within the species intercross frequently.
The genome of Cucumis melo was first sequenced in 2012. Some authors treat C. melo as having two subspecies, C. melo agrestis and C. melo melo. Varian... | Cucumis melo | Wikipedia | 489 | 23546532 | https://en.wikipedia.org/wiki/Cucumis%20melo | Biology and health sciences | Cucurbitales | null |
Uses
In addition to their consumption when fresh, melons are sometimes dried. Other varieties are cooked, or grown for their seeds, which are processed to produce melon oil. Still other varieties are grown only for their pleasant fragrance. The Japanese liqueur Midori is flavored with melon.
It was once a frequently c... | Cucumis melo | Wikipedia | 272 | 23546532 | https://en.wikipedia.org/wiki/Cucumis%20melo | Biology and health sciences | Cucurbitales | null |
The Monsoon of South Asia is among several geographically distributed global monsoons. It affects the Indian subcontinent, where it is one of the oldest and most anticipated weather phenomena and an economically important pattern every year from June through September, but it is only partly understood and notoriously d... | Monsoon of South Asia | Wikipedia | 496 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Alternatively, it can be categorized into two segments based on the direction of rain-bearing winds:
Southwest (SW) monsoon
Northeast (NE) monsoon
Based on the time of year that these winds bring rain to India, the monsoon can also be categorized into two periods:
Summer monsoon (May to September)
Winter monsoon ... | Monsoon of South Asia | Wikipedia | 332 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
The unique geographic relief features of the Indian subcontinent come into play in allowing all of the above factors to occur simultaneously. The relevant features in explaining the monsoon mechanism are as follows:
The presence of abundant water bodies around the subcontinent: the Arabian Sea, Bay of Bengal, and Indi... | Monsoon of South Asia | Wikipedia | 467 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Normally, the southwest monsoon can be expected to "burst" onto the western coast of India (near Thiruvananthapuram) at the beginning of June and to cover the entire country by mid-July. Its withdrawal from India typically starts at the beginning of September and finishes by the beginning of October.
The northeast mon... | Monsoon of South Asia | Wikipedia | 314 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Also known as the thermal theory or the differential heating of sea and land theory, the traditional theory portrays the monsoon as a large-scale sea breeze. It states that during the hot subtropical summers, the massive landmass of the Indian Peninsula heats up at a different rate than the surrounding seas, resulting ... | Monsoon of South Asia | Wikipedia | 431 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Process of monsoon creation
The dynamic theory explains the monsoon on the basis of the annual shifts in the position of global belts of pressure and winds. According to this theory, the monsoon is a result of the shift of the Intertropical Convergence Zone (ITCZ) under the influence of the vertical sun. Though the mea... | Monsoon of South Asia | Wikipedia | 471 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Over India, a subtropical westerly jet develops in the winter season and is replaced by the tropical easterly jet in the summer season. The high temperature during the summer over the Tibetan Plateau, as well as over Central Asia in general, is believed to be the critical factor leading to the formation of the tropical... | Monsoon of South Asia | Wikipedia | 339 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Jet stream theory
According to this theory, the onset of the southwest monsoon is driven by the shift of the subtropical westerly jet north from over the plains of India toward the Tibetan Plateau. This shift is due to the intense heating of the plateau during the summer months. The northward shift is not a slow and gr... | Monsoon of South Asia | Wikipedia | 376 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Southern Oscillation, a phenomenon first observed by Sir Gilbert Walker, director general of observatories in India, refers to the seesaw relationship of atmospheric pressures between Tahiti and Darwin, Australia. Walker noticed that when pressure was high in Tahiti, it was low in Darwin, and vice versa. A Southern Osc... | Monsoon of South Asia | Wikipedia | 475 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
A positive IOD index often negates the effect of ENSO, resulting in increased monsoon rains in years such as 1983, 1994, and 1997. Further, the two poles of the IOD – the eastern pole (around Indonesia) and the western pole (off the African coast) — independently and cumulatively affect the quantity of monsoon rains.
... | Monsoon of South Asia | Wikipedia | 497 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Seasonal Prediction of Indian Monsoon (SPIM)
The Centre for Development of Advanced Computing (CDAC) at Bengaluru facilitated the Seasonal Prediction of Indian Monsoon (SPIM) experiment on the PARAM Padma supercomputing system.
This project involved simulated runs of historical data from 1985 to 2004 to try to establis... | Monsoon of South Asia | Wikipedia | 395 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Agricultural
In India, which has historically had a primarily agrarian economy, the services sector recently overtook the farm sector in terms of GDP contribution. However, the agriculture sector still contributes 17–20% of GDP and is the largest employer in the country, with about 60% of Indians dependent on it for em... | Monsoon of South Asia | Wikipedia | 406 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
Social
D. Subbarao, former governor of the Reserve Bank of India, emphasized during a quarterly review of India's monetary policy that the lives of Indians depend on the performance of the monsoon. His own career prospects, his emotional well-being, and the performance of his monetary policy are all "a hostage" to the ... | Monsoon of South Asia | Wikipedia | 322 | 31096097 | https://en.wikipedia.org/wiki/Monsoon%20of%20South%20Asia | Physical sciences | Seasons | Earth science |
The Wu experiment was a particle and nuclear physics experiment conducted in 1956 by the Chinese American physicist Chien-Shiung Wu in collaboration with the Low Temperature Group of the US National Bureau of Standards. The experiment's purpose was to establish whether or not conservation of parity (P-conservation), wh... | Wu experiment | Wikipedia | 469 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
Theoretical physicists Tsung-Dao Lee and Chen-Ning Yang did a literature review on the question of parity conservation in all fundamental interactions. They concluded that in the case of the weak interaction, experimental data neither confirmed nor refuted P-conservation. Shortly after, they approached Chien-Shiung Wu,... | Wu experiment | Wikipedia | 424 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
Theory
If a particular interaction respects parity symmetry, it means that if left and right were interchanged, the interaction would behave exactly as it did before the interchange. Another way this is expressed is to imagine that two worlds are constructed that differ only by parity—the "real" world and the "mirror" ... | Wu experiment | Wikipedia | 390 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
Experiment
The experiment monitored the decay of cobalt-60 (60Co) atoms that were aligned by a uniform magnetic field (the polarizing field) and cooled to near absolute zero so that thermal motions did not ruin the alignment. Cobalt-60 is an unstable isotope of cobalt that decays by beta decay to the stable isotope nic... | Wu experiment | Wikipedia | 416 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
The experiment then essentially counted the rate of emission for gamma rays and electrons in two distinct directions and compared their values. This rate was measured over time and with the polarizing field oriented in opposite directions. If the counting rates for the electrons did not differ significantly from those ... | Wu experiment | Wikipedia | 421 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
In the experiment carried out by Wu, the gamma ray anisotropy was approximately 0.6. That is, approximately 60% of the electrons were emitted in one direction, where as 40% were emitted in the other. If parity were conserved in beta decay, the emitted electrons would have had no preferred direction of decay relative to... | Wu experiment | Wikipedia | 344 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
The results of the Wu experiment provide a way to operationally define the notion of left and right. This is inherent in the nature of the weak interaction. Previously, if the scientists on Earth were to communicate with a newly discovered planet's scientist, and they had never met in person, it would not have been pos... | Wu experiment | Wikipedia | 427 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
From experiments such as the Wu experiment and the Goldhaber experiment, it was determined that massless neutrinos must be left-handed, while massless antineutrinos must be right-handed. Since it is currently known that neutrinos have a small mass, it has been proposed that right-handed neutrinos and left-handed antine... | Wu experiment | Wikipedia | 479 | 36284621 | https://en.wikipedia.org/wiki/Wu%20experiment | Physical sciences | Quantum mechanics | Physics |
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. Biological membranes include cell membranes (outer coverings of cells or organ... | Membrane | Wikipedia | 447 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Ultrafiltration removes particles higher than 0.005-2 μm and operates within a range of 70-700kPa. Ultrafiltration is used for many of the same applications as microfiltration. Some ultrafiltration membranes have also been used to remove dissolved compounds with high molecular weight, such as proteins and carbohydrate... | Membrane | Wikipedia | 508 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Membrane configurations
In the membrane field, the term module is used to describe a complete unit composed of the membranes, the pressure support structure, the feed inlet, the outlet permeate and retentate streams, and an overall support structure. The principal types of membrane modules are:
Tubular, where membrane... | Membrane | Wikipedia | 508 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
The permeability (k) [m·s−2·bar−1] of a membrane is given by the next equation:
The trans-membrane pressure (TMP) is given by the following expression:
where PTMP is the trans-membrane pressure [kPa], Pf the inlet pressure of feed stream [kPa]; Pc the pressure of concentrate stream [kPa]; Pp the pressure if permeate... | Membrane | Wikipedia | 491 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
For cross-flow processes, the deposition of material will continue until the forces of the binding cake to the membrane will be balanced by the forces of the fluid. At this point, cross-flow filtration will reach a steady-state condition , and thus, the flux will remain constant with time. Therefore, this configuration... | Membrane | Wikipedia | 467 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Physical cleaning techniques for membrane include membrane relaxation and membrane backwashing.
Back-washing or back-flushing consists of pumping the permeate in the reverse direction through the membrane. Back-washing removes successfully most of the reversible fouling caused by pore blocking. Backwashing can also be ... | Membrane | Wikipedia | 334 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Reducing flux. The flux always reduces fouling but it impacts on capital cost since it demands more membrane area. It consists of working at sustainable flux which can be defined as the flux for which the TMP increases gradually at an acceptable rate, such that chemical cleaning is not necessary.
Using cross-flow filtr... | Membrane | Wikipedia | 454 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
RO membranes have some environmental challenges that must be resolved in order to comply with the circular economy principles. Mainly they have a short service life of 5–10 years. Over the past two decades, the number of RO desalination plants has increased by 70%. The size of these RO plants has also increased signifi... | Membrane | Wikipedia | 314 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Reuse of RO membranes include the direct reapplication of modules in other separation processes with less stringent specifications. The conversion from the RO TFC membrane to a porous membrane is possible by degrading the dense layer of polyamide. Converting RO membranes by chemical treatment with different oxidizing s... | Membrane | Wikipedia | 459 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Mechanical recycling characteristics:
A first separation of the components of interest is needed.
Previous washing to avoid property deterioration during the process.
Grinding of the polymeric materials into suitable size (loss of 5% of the material).
Possible posterior washing.
Melting and extrusion process (loss of 1... | Membrane | Wikipedia | 368 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Post-treatment
After applying the chosen technique, it is necessary to carry out a post-treatment process to ensure that the membrane can function normally again.
The first step in post-treatment involves removing all residual waste from the equipment. This ensures that no contaminants remain that could affect the memb... | Membrane | Wikipedia | 511 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Membranes are used with pressure as the driving processes in membrane filtration of solutes and in reverse osmosis. In dialysis and pervaporation the chemical potential along a concentration gradient is the driving force. Also perstraction as a membrane assisted extraction process relies on the gradient in chemical pot... | Membrane | Wikipedia | 141 | 26456640 | https://en.wikipedia.org/wiki/Membrane | Physical sciences | Other separations | Chemistry |
Ammonium dihydrogen phosphate (ADP), also known as monoammonium phosphate (MAP) is a chemical compound with the chemical formula (NH4)(H2PO4). ADP is a major ingredient of agricultural fertilizers and dry chemical fire extinguishers. It also has significant uses in optics and electronics.
Chemical properties
Monoammo... | Ammonium dihydrogen phosphate | Wikipedia | 491 | 23552434 | https://en.wikipedia.org/wiki/Ammonium%20dihydrogen%20phosphate | Physical sciences | Phosphoric oxyanions | Chemistry |
Toys
Being relatively non-toxic, MAP is also a popular substance for recreational crystal growing, being sold as toy kits mixed with dyes of various colors.
Natural occurrence
The compound appears in nature as the rare mineral biphosphammite. It is formed in guano deposits. A related compound, that is the monohydrogen... | Ammonium dihydrogen phosphate | Wikipedia | 81 | 23552434 | https://en.wikipedia.org/wiki/Ammonium%20dihydrogen%20phosphate | Physical sciences | Phosphoric oxyanions | Chemistry |
Grifola frondosa (also known as hen-of-the-woods, in Japanese, ram's head or sheep's head) is a polypore mushroom that grows at the base of trees, particularly old growth oaks or maples. It is native to China, Europe, and North America.
Description
Like the sulphur shelf mushroom, G. frondosa is a perennial fungus th... | Grifola frondosa | Wikipedia | 453 | 23555003 | https://en.wikipedia.org/wiki/Grifola%20frondosa | Biology and health sciences | Edible fungi | Plants |
The siemens (symbol: S) is the unit of electric conductance, electric susceptance, and electric admittance in the International System of Units (SI). Conductance, susceptance, and admittance are the reciprocals of resistance, reactance, and impedance respectively; hence one siemens is equal to the reciprocal of one ohm... | Siemens (unit) | Wikipedia | 479 | 31109470 | https://en.wikipedia.org/wiki/Siemens%20%28unit%29 | Physical sciences | Electromagnetism | null |
The inverted capital omega symbol (℧), while not an official SI abbreviation, is less likely to be confused with a variable than the letter "S" when writing the symbol by hand. The usual typographical distinctions (such as italic for variables and roman for units) are difficult to maintain. Likewise, it is difficult to... | Siemens (unit) | Wikipedia | 150 | 31109470 | https://en.wikipedia.org/wiki/Siemens%20%28unit%29 | Physical sciences | Electromagnetism | null |
UY Scuti (BD-12°5055) is a red supergiant star, located 5,900 light-years away in the constellation Scutum. It is also a pulsating variable star, with a maximum brightness of magnitude 8.29 and a minimum of magnitude 10.56, which is too dim for naked-eye visibility. It is considered to be one of the largest known stars... | UY Scuti | Wikipedia | 413 | 40502503 | https://en.wikipedia.org/wiki/UY%20Scuti | Physical sciences | Notable stars | Astronomy |
In mid 2012, AMBER interferometry with the Very Large Telescope (VLT) in the Atacama Desert in Chile was used to measure the parameters of three red supergiants near the Galactic Center region: UY Scuti, AH Scorpii, and KW Sagittarii. They determined that all three stars are over 1,000 times bigger than the Sun and ove... | UY Scuti | Wikipedia | 491 | 40502503 | https://en.wikipedia.org/wiki/UY%20Scuti | Physical sciences | Notable stars | Astronomy |
After fusing heavy elements, its core will begin to produce iron, disrupting the balance of gravity and radiation in its core and resulting in a core collapse supernova. It is expected that a star like UY Scuti should evolve back to hotter temperatures to become a yellow hypergiant, luminous blue variable, or a Wolf–Ra... | UY Scuti | Wikipedia | 107 | 40502503 | https://en.wikipedia.org/wiki/UY%20Scuti | Physical sciences | Notable stars | Astronomy |
Matoke, locally also known as matooke, amatooke in Buganda (Central Uganda), ekitookye in southwestern Uganda, ekitooke in western Uganda, kamatore in Lugisu (Eastern Uganda), ebitooke in northwestern Tanzania, igitoki in Rwanda, Burundi and by the cultivar name East African Highland banana, are a group of starchy trip... | Matoke | Wikipedia | 466 | 32104696 | https://en.wikipedia.org/wiki/Matoke | Biology and health sciences | Tropical and tropical-like fruit | Plants |
Taxonomy
East African Highland bananas are triploid (AAA) cultivars. Their official designation is Musa acuminata Colla (AAA-EA). Synonyms include Musa brieyi De Wild. Their paternal parent is the blood banana subspecies (M. acuminata ssp. zebrina) of the wild banana species Musa acuminata.
East African Highland bana... | Matoke | Wikipedia | 347 | 32104696 | https://en.wikipedia.org/wiki/Matoke | Biology and health sciences | Tropical and tropical-like fruit | Plants |
Origin and distribution
East African Highland bananas were introduced early into Africa from Southeast Asia during the first to sixth centuries AD, probably via trade. They are genetically distinct from the other AAA cultivars, having evolved locally in the African Great Lakes region for over a millennium. They are fo... | Matoke | Wikipedia | 430 | 32104696 | https://en.wikipedia.org/wiki/Matoke | Biology and health sciences | Tropical and tropical-like fruit | Plants |
Food preparation
Matoke are peeled using a knife, wrapped in the plant's leaves (or plastic bags), and set in a cooking pot (Swahili: sufuria) atop the banana stalks. The pot is then placed on a charcoal or wood fire and the matoke is steamed for a couple of hours; water is poured into the bottom of the cooking pot mu... | Matoke | Wikipedia | 291 | 32104696 | https://en.wikipedia.org/wiki/Matoke | Biology and health sciences | Tropical and tropical-like fruit | Plants |
Herpes esophagitis is a viral infection of the esophagus caused by Herpes simplex virus (HSV).
While the disease most often occurs in immunocompromised patients, including post-chemotherapy, immunosuppression with organ transplants and in AIDS, herpes esophagitis can also occur in immunocompetent individuals.
Signs a... | Herpes esophagitis | Wikipedia | 470 | 26465940 | https://en.wikipedia.org/wiki/Herpes%20esophagitis | Biology and health sciences | Viral diseases | Health |
Treatment
Antivirals such as acyclovir, famciclovir, or valacyclovir may be used. Intravenous acyclovir is reserved for individuals who cannot swallow due to the pain, individuals with other systemic manifestations of herpes or severely immunocompromised individuals. | Herpes esophagitis | Wikipedia | 67 | 26465940 | https://en.wikipedia.org/wiki/Herpes%20esophagitis | Biology and health sciences | Viral diseases | Health |
Soldering (; ) is a process of joining two metal surfaces together using a filler metal called solder. The soldering process involves heating the surfaces to be joined and melting the solder, which is then allowed to cool and solidify, creating a strong and durable joint.
Soldering is commonly used in the electronics ... | Soldering | Wikipedia | 512 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Electronic soldering connects electrical wiring to devices, and electronic components to printed circuit boards. Electronic connections may be hand-soldered with a soldering iron. Automated methods such as wave soldering or use of ovens can make many joints on a complex circuit board in one operation, vastly reducing ... | Soldering | Wikipedia | 398 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
A eutectic formulation has advantages when applied to soldering: the liquidus and solidus temperatures are the same, so there is no plastic phase, and it has the lowest possible melting point. Having the lowest possible melting point minimizes heat stress on electronic components during soldering. And, having no plasti... | Soldering | Wikipedia | 512 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
The alloy of the filler metal for each type of soldering can be adjusted to modify the melting temperature of the filler. Soldering differs from gluing significantly in that the filler metals directly bond with the surfaces of the workpieces at the junction to form a bond that is both electrically conductive and gas- a... | Soldering | Wikipedia | 493 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Soldering operations can be performed with hand tools, one joint at a time, or en masse on a production line. Hand soldering is typically performed with a soldering iron, soldering gun, or a torch, or occasionally a hot-air pencil. Sheetmetal work was traditionally done with "soldering coppers" directly heated by a fla... | Soldering | Wikipedia | 473 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Since the joint is produced using a metal with a lower melting temperature than the workpiece, the joint will weaken as the ambient temperature approaches the melting point of the filler metal. For that reason, the higher temperature processes produce joints which are effective at higher temperatures. Brazed connection... | Soldering | Wikipedia | 460 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
The American Welding Society defines brazing as using filler metals with melting points over — or, by the traditional definition in the United States, above . Aluminium soldering alloys generally have melting temperatures around . This soldering / brazing operation can use a propane torch heat source.
These materials... | Soldering | Wikipedia | 488 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Fluxes for soft solder are currently available in three basic formulations:
Water-soluble fluxes – higher activity fluxes which can be removed with water after soldering (no VOCs required for removal).
No-clean fluxes – mild enough to not "require" removal due to their non-conductive and non-corrosive residues. These... | Soldering | Wikipedia | 352 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Heating methods
Different types of soldering tools are made for specific applications. The required heat can be generated from burning fuel or from an electrically operated heating element or by passing an electric current through the item to be soldered. Another method for soldering is to place solder and flux at the ... | Soldering | Wikipedia | 438 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
A soldering gun heats a small cross-section copper tip very quickly by conducting a large AC current through it using a large cross-section one-turn transformer; the copper tip then conducts the heat to the part like other soldering irons. A soldering gun will be larger and heavier than a heating-element soldering iron... | Soldering | Wikipedia | 424 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
During WW2 and for some time afterwards SOE forces used small pyrotechnic self-soldering joints to make connections for the remote detonation of demolition and sabotage explosives. These consisted of a small copper tube partially filled with solder and a slow-burning pyrotechnic composition wrapped around the tube. The... | Soldering | Wikipedia | 488 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Induction soldering
Induction soldering uses induction heating by high-frequency alternating current in a surrounding copper coil. This induces currents in the part being soldered, which generates heat because of the higher resistance of a joint versus its surrounding metal (resistive heating). These copper coils can b... | Soldering | Wikipedia | 505 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Resistance soldering equipment, unlike conduction irons, can be used for difficult soldering and brazing applications where significantly higher temperatures may be required. This makes resistance comparable to flame soldering in some situations, but the resistance heat is more localized because of direct contact, wher... | Soldering | Wikipedia | 323 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Outside the United States, "sweating" refers to the joining of flat metallic surfaces by a two step process by which solder is first applied to one surface, then this first piece is placed in position against the second surface and both are re-heated to achieve the desired joint.
Copper tubing conducts heat away much... | Soldering | Wikipedia | 460 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
As with all solder joints, all parts to be joined must be clean and oxide free. Internal and external wire brushes are available for the common pipe and fitting sizes; emery cloth and wire-wool are frequently used as well, although metal wool products are discouraged, as they can contain oil, which would contaminate th... | Soldering | Wikipedia | 267 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Since copper pipe quickly conducts heat away from a joint, great care must be taken to ensure that the joint is properly heated through to obtain a good bond. After the joint is properly cleaned, fluxed and fitted, the torch flame is applied to the thickest part of the joint, typically the fitting with the pipe inside ... | Soldering | Wikipedia | 488 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
When soldering pipes closely connected to valves such as in refrigeration systems it may be necessary to protect the valve from heat that could damage rubber or plastic components within, in this case a wet cloth wrapped around the valve can often sink sufficient heat through the boiling of the water to protect the val... | Soldering | Wikipedia | 463 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Electronic joints are usually made between surfaces that have been tinned and rarely require mechanical cleaning, though tarnished component leads and copper traces with a dark layer of oxide passivation (due to aging), as on a new prototyping board that has been on the shelf for about a year or more, may need to be me... | Soldering | Wikipedia | 503 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
A cold-soldered joint may not conduct at all, or may conduct only intermittently. Cold-soldered joints also happen in mass production, and are a common cause of equipment which passes testing, but malfunctions after sometimes years of operation.
Dry joints
A "dry joint" occurs when the cooling solder is moved. Since n... | Soldering | Wikipedia | 475 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Visual inspection of joints
When visually inspected, a good solder joint will appear smooth, bright and shiny, with the outline of the soldered wire clearly visible. In general a good-looking soldered joint is a good joint.
A matte gray surface is a good indicator of a joint that was moved during soldering. A dry join... | Soldering | Wikipedia | 491 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Some fluxes are corrosive and flux residue must be removed after soldering. If not properly cleaned, the flux may corrode the joint or the PCB. Water, alcohol, acetone, or other solvents compatible with the flux and the parts involved are commonly used with cotton swabs or bristle brushes.
In some applications, the PC... | Soldering | Wikipedia | 494 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Reflow soldering is a process in which a solder paste (a mixture of prealloyed solder powder and a flux-vehicle that has a peanut butter-like consistency) is used to stick the components to their attachment pads, after which the assembly is heated by an infrared lamp, a hot air pencil, or, more commonly, by passing it ... | Soldering | Wikipedia | 450 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Lead free soldering requires higher soldering temperatures than lead/tin soldering. SnPb 63/37 eutectic solder melts at . SAC lead-free solder melts at .
Nevertheless, many new technical challenges have arisen with this endeavor. To reduce the melting point of tin-based solder alloys, various new alloys have had to b... | Soldering | Wikipedia | 237 | 25067088 | https://en.wikipedia.org/wiki/Soldering | Technology | Metallurgy | null |
Jameson's mamba (Dendroaspis jamesoni) is a species of highly venomous snake in the family Elapidae. The species is native to equatorial Africa. A member of the mamba genus, Dendroaspis, it is slender with dull green upper parts and cream underparts and generally ranges from in total length. Described by Scottish natu... | Jameson's mamba | Wikipedia | 499 | 33704019 | https://en.wikipedia.org/wiki/Jameson%27s%20mamba | Biology and health sciences | Snakes | Animals |
Description
Jameson's mamba is a long and slender snake with smooth scales and a tail which typically accounts for 20 to 25% of its total length. The total length (including tail) of an adult snake is approximately . It may grow as large as . The general consensus is that the sexes are of similar sizes, although fieldw... | Jameson's mamba | Wikipedia | 372 | 33704019 | https://en.wikipedia.org/wiki/Jameson%27s%20mamba | Biology and health sciences | Snakes | Animals |
Jameson's mamba occurs mostly in Central Africa and West Africa, and in some parts of East Africa. In Central Africa it can be found from Angola northwards to the Democratic Republic of the Congo, Republic of the Congo, Central African Republic, and as far north as the Imatong Mountains of South Sudan. In West Africa i... | Jameson's mamba | Wikipedia | 440 | 33704019 | https://en.wikipedia.org/wiki/Jameson%27s%20mamba | Biology and health sciences | Snakes | Animals |
Diet and predators
Jameson's mamba has been difficult to study in the field due to its arboreal nature and green coloration. It has not been observed hunting but is thought to use a sit-and-wait strategy, which has been reported for the eastern green mamba. The bulk of its diet is made up of birds and tree-dwelling mam... | Jameson's mamba | Wikipedia | 358 | 33704019 | https://en.wikipedia.org/wiki/Jameson%27s%20mamba | Biology and health sciences | Snakes | Animals |
Like other mambas, the venom of the Jameson's mamba is highly neurotoxic. Symptoms of envenomation by this species include pain and swelling of the bite site. Systemic effects include generalised swelling, chills, sweating, abdominal pain and vomiting, with subsequent slurred speech, difficulty breathing, and paralysis... | Jameson's mamba | Wikipedia | 490 | 33704019 | https://en.wikipedia.org/wiki/Jameson%27s%20mamba | Biology and health sciences | Snakes | Animals |
A colored pencil (American English), coloured pencil (Commonwealth English), colour pencil (Indian English), map pencil, pencil crayon, or coloured/colouring lead (Canadian English, Newfoundland English) is a type of pencil constructed of a narrow, pigmented core encased in a wooden cylindrical case. Unlike graphite a... | Colored pencil | Wikipedia | 407 | 40516793 | https://en.wikipedia.org/wiki/Colored%20pencil | Technology | Artist's and drafting tools | null |
Although colored pencils had been used for “checking and marking” for decades prior, it was not until the early 20th century that artist-quality colored pencils were produced. Manufacturers that began producing artist-grade colored pencils included Faber-Castell in 1908 (the Polychromos range was initially 60 colors) a... | Colored pencil | Wikipedia | 431 | 40516793 | https://en.wikipedia.org/wiki/Colored%20pencil | Technology | Artist's and drafting tools | null |
Watercolor pencils, otherwise known as water-soluble pencils, are a versatile art medium. The pencils can be used dry—like normal colored pencils—or they can be applied wet to get the desired watercolor effect. In wet application, the artist first lays down the dry pigment and then follows up with a damp paintbrush to ... | Colored pencil | Wikipedia | 354 | 40516793 | https://en.wikipedia.org/wiki/Colored%20pencil | Technology | Artist's and drafting tools | null |
Layering is usually used in the beginning stages of a colored pencil drawing, but can also be used for entire pieces. In layering, tones are gradually built up using several layers of primary colors. Layered drawings usually expose the tooth of the paper and are characterized by a grainy, fuzzy finish.
Burnishing is a ... | Colored pencil | Wikipedia | 258 | 40516793 | https://en.wikipedia.org/wiki/Colored%20pencil | Technology | Artist's and drafting tools | null |
Radioanalytical chemistry focuses on the analysis of sample for their radionuclide content. Various methods are employed to purify and identify the radioelement of interest through chemical methods and sample measurement techniques.
History
The field of radioanalytical chemistry was originally developed by Marie C... | Radioanalytical chemistry | Wikipedia | 475 | 23568658 | https://en.wikipedia.org/wiki/Radioanalytical%20chemistry | Physical sciences | Basics_2 | Chemistry |
Gaseous ionization detectors collect and record the electrons freed from gaseous atoms and molecules by the interaction of radiation released by the source. A voltage potential is applied between two electrodes within a sealed system. Since the gaseous atoms are ionized after they interact with radiation they are att... | Radioanalytical chemistry | Wikipedia | 504 | 23568658 | https://en.wikipedia.org/wiki/Radioanalytical%20chemistry | Physical sciences | Basics_2 | Chemistry |
Since small amounts of radionuclides are typically being analyzed, the mechanics of manipulating tiny quantities is challenging. This problem is classically addressed by the use of carrier ions. Thus, carrier addition involves the addition of a known mass of stable ion to radionuclide-containing sample solution. The ... | Radioanalytical chemistry | Wikipedia | 511 | 23568658 | https://en.wikipedia.org/wiki/Radioanalytical%20chemistry | Physical sciences | Basics_2 | Chemistry |
Occupational safety and health (OSH) or occupational health and safety (OHS) is a multidisciplinary field concerned with the safety, health, and welfare of people at work (i.e., while performing duties required by one's occupation). OSH is related to the fields of occupational medicine and occupational hygiene and alig... | Occupational safety and health | Wikipedia | 511 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
History
Research and regulation of occupational safety and health are a relatively recent phenomenon. As labor movements arose in response to worker concerns in the wake of the industrial revolution, workers' safety and health entered consideration as a labor-related issue.
Beginnings
Written works on occupational d... | Occupational safety and health | Wikipedia | 469 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
The United Kingdom was the first nation to industrialize. Soon shocking evidence emerged of serious physical and moral harm suffered by children and young persons in the cotton textile mills, as a result of exploitation of cheap labor in the factory system. Responding to calls for remedial action from philanthropists a... | Occupational safety and health | Wikipedia | 509 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
The first decennial British Registrar-General's mortality report was issued in 1851. Deaths were categorized by social classes, with class I corresponding to professionals and executives and class V representing unskilled workers. The report showed that mortality rates increased with the class number.
Continental Euro... | Occupational safety and health | Wikipedia | 508 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
Physical hazards affect many people in the workplace. Occupational hearing loss is the most common work-related injury in the United States, with 22 million workers exposed to hazardous occupational noise levels at work and an estimated $242 million spent annually on worker's compensation for hearing loss disability. F... | Occupational safety and health | Wikipedia | 449 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
Psychosocial hazards include risks to the mental and emotional well-being of workers, such as feelings of job insecurity, long work hours, and poor work-life balance. Psychological abuse has been found present within the workplace as evidenced by previous research. A study by Gary Namie on workplace emotional abuse fou... | Occupational safety and health | Wikipedia | 489 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
The mining industry still has one of the highest rates of fatalities of any industry. There are a range of hazards present in surface and underground mining operations. In surface mining, leading hazards include such issues as geological instability, contact with plant and equipment, rock blasting, thermal environments... | Occupational safety and health | Wikipedia | 482 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
The 2010 National Health Interview Survey Occupational Health Supplement (NHIS-OHS) identified work organization factors and occupational psychosocial and chemical/physical exposures which may increase some health risks. Among all US workers in the construction sector, 44% had non-standard work arrangements (were not r... | Occupational safety and health | Wikipedia | 507 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
In addition to these organizational risks, some industries pose significant physical dangers due to the manual labor involved. For instance, on a per employee basis, the US Postal Service, UPS and FedEx are the 4th, 5th and 7th most dangerous companies to work for in the United States, respectively.
Healthcare and soc... | Occupational safety and health | Wikipedia | 496 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
European Union
Certain EU member states admit to having lacking quality control in occupational safety services, to situations in which risk analysis takes place without any on-site workplace visits and to insufficient implementation of certain EU OSH directives. Disparities between member states result in different i... | Occupational safety and health | Wikipedia | 487 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
Further problems in the accounting of workplace fatalities arise from the fact that multiple Russian federal entities collect and publish records, a practice that should be avoided. In 2008 alone, 2074 accidents at work may have not been reported in official government sources.
United Kingdom
In the UK there were 135... | Occupational safety and health | Wikipedia | 479 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
About 3.5 million nonfatal workplace injuries and illnesses were reported by private industry employers in 2022, occurring at a rate of 3.0 cases per 100 full-time workers.
Management systems
Companies may adopt a safety and health management system (SMS), either voluntarily or because required by applicable regulati... | Occupational safety and health | Wikipedia | 464 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
National
National management system standards for occupational health and safety include AS/NZS 4801 for Australia and New Zealand (now superseded by ISO 45001), CSA Z1000:14 for Canada (which is due to be discontinued in favor of CSA Z45001:19, the Canadian adoption of ISO 45000) and ANSI/ASSP Z10 for the United S... | Occupational safety and health | Wikipedia | 399 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
Hazard identification
Hazard identification is an important step in the overall risk assessment and risk management process. It is where individual work hazards are identified, assessed and controlled or eliminated as close to source (location of the hazard) as reasonably practicable. As technology, resources, social e... | Occupational safety and health | Wikipedia | 473 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
The assessment should be recorded and reviewed periodically and whenever there is a significant change to work practices. The assessment should include practical recommendations to control the risk. Once recommended controls are implemented, the risk should be re-calculated to determine if it has been lowered to an acc... | Occupational safety and health | Wikipedia | 473 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
In China, the Ministry of Health is responsible for occupational disease prevention and the State Administration of Work Safety workplace safety issues. The Work Safety Law (安全生产法) was issued on 1 November 2002. The Occupational Disease Control Act came into force on 1 May 2002. In 2018, the National Health Commission ... | Occupational safety and health | Wikipedia | 405 | 35319154 | https://en.wikipedia.org/wiki/Occupational%20safety%20and%20health | Biology and health sciences | Health and fitness | null |
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