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Section: Early life and education. She was inspired to pursue a life of science after reading a book on Marie Curie, the great physicist and Nobel Prize winner, that was given to her by one of the French nuns at the library. She refers to this instance as a "turning point" in her life where she realized that a woman wh... | Wikipedia - Huda Akil - Early life and education | 329 | 1,674 | null |
Section: Career and research. Akil's research covers many areas, but is collectively rooted in understanding emotions. Throughout her career her research has included work on opiate receptors, structure function analyses, behavioral studies, the neurobiology of severe psychiatric disorder, post mortem brains, and molec... | Wikipedia - Huda Akil - Career and research | 337 | 1,671 | null |
Further research in this area was conducted in the rat by employing the D'Amour and Smith tail flick test in order to investigate role played by the cerebral monoamines, dopamine, noradrenaline, and serotonin. Akil and colleagues used four different approaches to alter transmission in monoamine pathways: depletion of m... | Wikipedia - Huda Akil - Career and research | 334 | 1,629 | null |
Essentially, they developed a model of stress induced analgesia that was naloxone responsive. Building on prior research, Akil and colleagues established that in the rat, inescapable acute stress causes a significant increase in the opioid peptides, enkephalins and endorphins with a concurrent reduction in pain respons... | Wikipedia - Huda Akil - Career and research | 324 | 1,584 | null |
Section: Honors and awards. Akil is a decorated scientist, who has been the recipient of numerous awards throughout her career. In 1993, she received the National Institute on Drug Abuse Pacesetter Award. The following year she was the co-recipient, with Stanley Watson, of the Robert J. and Claire Pasarow Foundation Me... | Wikipedia - Huda Akil - Honors and awards | 320 | 1,620 | null |
Section: Early life. Graduating from the University of Arizona with a BS in Biological Sciences (1975), Aldrich went on to earn a Ph. D. in Neuroscience from Stanford University (1980). After completing a post-doctoral fellowship in physiology at Yale University under the direction of W. Knox Chandler and Charles F. St... | Wikipedia - Richard W. Aldrich - Early life | 215 | 1,062 | null |
Section: Life. He graduated from University of Chicago with a PhD in anthropology. In 2000, Allman's laboratory reported identification of a class of neurons - large spindle-shaped cells - unique to humans and our closest relatives, the great apes. The spindle neurons, now called the Von Economo neurons to distinguish ... | Wikipedia - John Allman - Life | 273 | 1,316 | null |
Section: Works. John Allman, Atiya Hakeem, J.M. Erwin, E. Nimchinsky, P. Hof (2001). 'Anterior cingulate cortex: The evolution of an interface between emotion and cognition', Annals of the New York Academy of Sciences, Vol 935, pp 107–117. John Allman, Atiya Hakeem, and Karli Watson (2002). 'Two phylogenetic specializa... | Wikipedia - John Allman - Works | 233 | 784 | null |
Section: First years. Born in Hungary to a Jewish family, he survived The Holocaust and migrated with his family via Germany and Australia to the United States. In these places, he sought employment as a librarian and used the opportunity to inform himself reading books about psychology, human behavior, psychoanalysis,... | Wikipedia - Joseph Altman - First years | 190 | 1,005 | null |
Section: Discovery of adult neurogenesis. Joseph Altman discovered adult neurogenesis, the creation of new neurons in the mammalian adult brain, in the 1960s. His research showed neuronal migration, i.e. the origin of the neocortical neurons from a zone of dividing cells lining the ventricles of the fetal brain and mig... | Wikipedia - Joseph Altman - Discovery of adult neurogenesis | 283 | 1,335 | null |
Section: Career. Amara was a faculty at Yale University and the Vollum Institute as an HHMI Investigator. She was elected as a member of the National Academy of Sciences in 2004, and became a fellow of the AAAS in 2007. Her main research interests are the parts of the brain that get activated when people take certain a... | Wikipedia - Susan Amara - Career | 315 | 1,521 | null |
She argued in favor of funding by citing past successful NIH-funded projects that helped researchers find new ways to treat mental health and neurological disorders. In January 2013, Amara joined the DIRP becoming the NIMH Scientific Director and continues her research in her new lab at the NIMH, the Laboratory of Mole... | Wikipedia - Susan Amara - Career | 263 | 1,281 | null |
Section: Research. Amaral is a specialist on the organization and functioning of the hippocampus, the amygdala and other parts of the primate and human brain. Amaral has directed several million dollars worth of research with grants from the National Institute of Mental Health (NIMH), which has included primate researc... | Wikipedia - David Amaral - Research | 249 | 1,196 | null |
Section: MIND Institute. Amaral was the founding Research Director of the MIND Institute. This institute was started at UC Davis in collaboration with the parents of children diagnosed with autism spectrum disorders. Amaral's research team is dedicated to understanding the biological and behavioral features of autism, ... | Wikipedia - David Amaral - MIND Institute | 189 | 1,058 | null |
Section: Biography. Andersen was born in New Kensington, Pennsylvania, on October 27, 1950. He received his undergraduate degree in biochemistry at the University of California, Davis, in 1973, working in the laboratory of Prof. Robert Scobey over two summers. Andersen then received his PhD in physiology under the ment... | Wikipedia - Richard A. Andersen (neuroscientist) - Biography | 333 | 1,739 | null |
Section: Research. Early work centered on the discovery and elucidation of cortical gain fields, a general rule of multiplicative computation used by many areas of the cortex. Andersen and Zipser of UCSD developed one of the first neural network models of cortical function, which generated a mathematical basis for test... | Wikipedia - Richard A. Andersen (neuroscientist) - Research | 350 | 1,848 | null |
Article: David J. Anderson. David Jeffrey Anderson (born 1956) is an American neurobiologist. He is a Howard Hughes Medical Institute investigator. His lab is located at the California Institute of Technology, where he currently holds the position of Seymour Benzer Professor of Biology, TianQiao and Chrissy Chen Leader... | Wikipedia - David J. Anderson - Summary | 153 | 761 | null |
Section: Clinical. A serious illness after the birth of her first daughter piqued Andreasen's interest in medicine and biomedical research, and she decided to change careers to study medicine. She attended medical school at the University of Iowa College of Medicine, graduated in 1970 and completed her psychiatry resid... | Wikipedia - Nancy Coover Andreasen - Clinical | 341 | 1,868 | null |
Section: Honors. In 2000 President Clinton awarded her the National Medal of Science, America's highest award for scientific achievement. This award was given for her pivotal contributions to the social and behavioral sciences, through the integrative study of mind, brain, and behavior, by joining behavioral science wi... | Wikipedia - Nancy Coover Andreasen - Honors | 299 | 1,645 | null |
Section: Career. Andrews' research career has been distinguished by advancing both basic and translational research questions in chemical neuroscience. She is the leader of an interdisciplinary research team at UCLA engaged in the development of innovative nanomaterial based in vivo biosensors for neurotransmitters. In... | Wikipedia - Anne M. Andrews - Career | 291 | 1,552 | null |
Section: Education, research, and service. Andrews grew up in Pittsburgh and discovered her passion for science, and most especially chemistry, during her middle school science classes. She would go on to receive her B.S. in Chemistry Pennsylvania State University where during her time as a student she was an intern in... | Wikipedia - Anne M. Andrews - Education, research, and service | 337 | 1,705 | null |
Article: A. V. Apkarian. Apkar Vania Apkarian is a professor of physiology, anesthesiology, and physical medicine and rehabilitation at Northwestern University, in the Feinberg School of Medicine. He has been a pioneer in the use of magnetic resonance spectroscopy to study the neurochemistry of the brain and the develo... | Wikipedia - A. V. Apkarian - Summary | 209 | 1,015 | null |
Section: Career. Dr. Apkarian's early work with primate electrophysiology established that thalamic neurons can be physiologically characterized based on morphology and projections to the cortex, which led to the discovery that the thalamus dynamically encodes nociceptive stimuli in response to features of sensory stim... | Wikipedia - A. V. Apkarian - Career | 340 | 1,745 | null |
Dr. Apkarian's research has increasingly focused on the translation of neuroimaging findings to improve clinical treatment of chronic pain, including the development of preventative treatments and the strategic use of placebo treatment. This work should hopefully traverse through the alleviation of clinical pain condit... | Wikipedia - A. V. Apkarian - Career | 346 | 1,761 | null |
Section: Works. Why God Won't Go Away: Brain Science and the Biology of Belief (2001) with Andrew Newberg (Author) and Vince Rause, Ballantine Books The Mystical Mind: Probing the Biology of Religious Experience (1999) with Andrew B. Newberg, Fortress Press Brain, Symbol and Experience: Toward a Neurophenomenology of H... | Wikipedia - Eugene G. d'Aquili - Works | 158 | 692 | null |
Article: Victoria Arango. Victoria Arango is an American neuroscientist who until 2017, was a Professor of Clinical Neurobiology (in Psychiatry) in the Department of Psychiatry at Columbia University. She was the director of the Diane Goldberg Laboratory for the Molecular Imaging of Neural Disorders (MIND) and the Labo... | Wikipedia - Victoria Arango - Summary | 340 | 1,871 | null |
Section: Recognition. In 2008, Arnsten received the Distinguished Investigator Award from the National Alliance for Research on Schizophrenia and Depression, to further her research on the neurobiology of mental illness. In 2013, she was given the National Institutes of Health Director's Pioneer Award in recognition of... | Wikipedia - Amy Arnsten - Recognition | 182 | 957 | null |
Section: Selected publications > Articles. Augustine, George J.; Charlton, Milton P.; Smith, Stephen J. (1987). "Calcium Action in Synaptic Transmitter Release". Annual Review of Neuroscience. 10: 633–693. doi:10.1146/annurev.ne.10.030187.003221. PMID 2436546. Smith, Stephen J.; Augustine, George J. (1988). "Calcium Io... | Wikipedia - George J. Augustine - Selected publications > Articles | 349 | 1,000 | null |
Section: Experience with Zen. Austin has been a practicing Zen Buddhist since 1974. He began in Kyoto at Daitoku-ji as a student of the Rinzai roshi Kobori Nanrei Sohaku. After eight years of regular Zen meditation, Austin experienced the taste of what Zen practice calls kenshō. The chief characteristic of this experie... | Wikipedia - James H. Austin - Experience with Zen | 335 | 1,506 | null |
Section: Research and career. During the late 1970s, Axel, along with microbiologist Saul J. Silverstein and geneticist Michael H. Wigler, discovered a technique of cotransformation via transfection, a process which allows foreign DNA to be inserted into a host cell to produce certain proteins. A family of patents, now... | Wikipedia - Richard Axel - Research and career | 319 | 1,643 | null |
Axel's primary research interest is on how the brain interprets the sense of smell, specifically mapping the parts of the brain that are sensitive to specific olfactory receptors. He holds the titles of University Professor at Columbia University, Professor of Biochemistry and Molecular Biophysics and of Pathology at C... | Wikipedia - Richard Axel - Research and career | 184 | 982 | null |
Section: Awards and honors. In addition to the Nobel Prize, Axel has won numerous awards and honors. He was elected a Fellow of the American Academy of Arts and Sciences and a member of the National Academy of Sciences in 1983. In 2005, Axel received the Golden Plate Award of the American Academy of Achievement. Axel w... | Wikipedia - Richard Axel - Awards and honors | 215 | 1,117 | null |
Section: Research > Analgesic research. In 1946, Axelrod took a position working under Bernard Brodie at Goldwater Memorial Hospital. The research experience and mentorship Axelrod received from Brodie would launch him on his research career. Brodie and Axelrod's research focused on how analgesics (pain-killers) work. ... | Wikipedia - Julius Axelrod - Research > Analgesic research | 161 | 692 | null |
Section: Research > Catecholamine research. In 1949, Axelrod began work at the National Heart Institute, forerunner of the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health (NIH). He examined the mechanisms and effects of caffeine, which led him to an interest in the sympathet... | Wikipedia - Julius Axelrod - Research > Catecholamine research | 327 | 1,397 | null |
Section: Research > Pineal gland research. Some of Axelrod's later research focused on the pineal gland. He and his colleagues showed that the hormone melatonin is generated from tryptophan, as is the neurotransmitter serotonin. The rates of synthesis and release follows the body's circadian rhythm driven by the suprac... | Wikipedia - Julius Axelrod - Research > Pineal gland research | 174 | 795 | null |
Section: Personal life > Political views. After receiving the Nobel Prize in 1970, Axelrod used his visibility to advocate several science policy issues. In 1973 U.S. President Richard Nixon created an agency with the specific goal of curing cancer. Axelrod, along with fellow Nobel-laureates Marshall W. Nirenberg and C... | Wikipedia - Julius Axelrod - Personal life > Political views | 152 | 783 | null |
Article: Bernard Baars. Bernard J. Baars (born 1946 in Amsterdam, the Netherlands) is a former Senior Fellow in Theoretical Neurobiology at the Neurosciences Institute in San Diego, US. He is currently an Affiliated Fellow there. He is best known as the originator of the global workspace theory, a concept of human cogn... | Wikipedia - Bernard Baars - Summary | 222 | 1,130 | null |
Section: Biography. Bach-y-Rita was born on April 4, 1934, in New York City to Anne Hyman and Pedro Bach-y-Rita, the latter a Catalan poet and teacher at City College of New York. He studied at the Bronx High School of Science, from which he graduated at the age of fifteen before studying at Mexico City College (now th... | Wikipedia - Paul Bach-y-Rita - Biography | 249 | 1,158 | null |
Section: Work in Sensory Substitution and Neuroplasticity. Bach-y-Rita's most notable work was in the field of neuroplasticity. He is seen as the first to propose the concept of sensory substitution to treat patients with disabilities, often those caused by neurological problems. One of the first applications of sensor... | Wikipedia - Paul Bach-y-Rita - Work in Sensory Substitution and Neuroplasticity | 180 | 914 | null |
Section: Work in Sensory Substitution and Neuroplasticity > Using Neuroplasticity to treat balance disorders. One of his last applications of neuroplasticity was to treat patients with damaged vestibular systems, meaning they were unable to remain balanced. The device he created (now sold as Brainport) consists of a gr... | Wikipedia - Paul Bach-y-Rita - Work in Sensory Substitution and Neuroplasticity > Using Neuroplasticity to treat balance disorders | 245 | 1,216 | null |
Section: Work in Sensory Substitution and Neuroplasticity > Research into neuroplasticity to treat stroke patients. In 1959, Bach-y-Rita's father, Pedro, had a cerebral infarction (stroke) which caused paralysis to one side of his body and damaged his ability to speak. George Bach-y-Rita—a psychiatrist and Paul's broth... | Wikipedia - Paul Bach-y-Rita - Work in Sensory Substitution and Neuroplasticity > Research into neuroplasticity to treat stroke patients | 182 | 830 | null |
Article: Rajendra Badgaiyan. Professor Rajendra D Badgaiyan (born 1955) is an Indian-American psychiatrist and cognitive neuroscientist. He is best known for developing a new neuroimaging technique for detection of acute changes in concentration of dopamine released in the live human brain during performance of a cogni... | Wikipedia - Rajendra Badgaiyan - Summary | 180 | 924 | null |
Section: Life. Badgaiyan was born and raised in India. He graduated with MBBS and MD degrees from Gandhi Medical College Bhopal and received an MA degree in psychology from Bhopal University. He taught neurophysiology in medical schools in Bhopal, Rohtak and Banaras Hindu University. In India, he was awarded a number o... | Wikipedia - Rajendra Badgaiyan - Life | 344 | 1,847 | null |
Article: Matthew J. Baggott. Matthew John Baggott is an American neuroscientist who studies entactogens, hallucinogens, and other psychoactive drugs. He is considered to be an expert on MDMA and other entactogens and is an influential figure in the psychedelic medicine movement. Baggott is co-founder and CEO of Tactoge... | Wikipedia - Matthew J. Baggott - Summary | 345 | 1,502 | null |
Section: Selected publications. Baggott M, Heifets B, Jones RT, Mendelson J, Sferios E, Zehnder J (November 2000). "Chemical analysis of ecstasy pills". JAMA. 284 (17): 2190. doi:10.1001/jama.284.17.2190. PMID 11056589. Lester SJ, Baggott M, Welm S, Schiller NB, Jones RT, Foster E, Mendelson J (December 2000). "Cardiov... | Wikipedia - Matthew J. Baggott - Selected publications | 344 | 1,030 | null |
ISBN 978-0-89281-857-0. Retrieved 24 November 2024. Harris DS, Baggott M, Mendelson JH, Mendelson JE, Jones RT (August 2002). "Subjective and hormonal effects of 3,4-methylenedioxymethamphetamine (MDMA) in humans". Psychopharmacology (Berl). 162 (4): 396–405. doi:10.1007/s00213-002-1131-1. PMID 12172693. Baggott, Matth... | Wikipedia - Matthew J. Baggott - Selected publications | 344 | 1,043 | null |
"Intimate insight: MDMA changes how people talk about significant others". J Psychopharmacol. 29 (6): 669–677. doi:10.1177/0269881115581962. PMC 4698152. PMID 25922420. Baggott MJ, Coyle JR, Siegrist JD, Garrison KJ, Galloway GP, Mendelson JE (April 2016). "Effects of 3,4-methylenedioxymethamphetamine on socioemotional... | Wikipedia - Matthew J. Baggott - Selected publications | 343 | 991 | null |
ISBN 9780963009661. OCLC 1176317484. Baggott MJ, Garrison KJ, Coyle JR, Galloway GP, Barnes AJ, Huestis MA, Mendelson JE (2019). "Effects of the Psychedelic Amphetamine MDA (3,4-Methylenedioxyamphetamine) in Healthy Volunteers". J Psychoactive Drugs. 51 (2): 108–117. doi:10.1080/02791072.2019.1593560. PMID 30967099. Ma... | Wikipedia - Matthew J. Baggott - Selected publications | 331 | 1,073 | null |
Article: Kristin Baldwin. Kristin K. Baldwin is an American scientist who is a professor at the Department of Genetics and Development at Columbia University. Her research focuses on using reprogrammed and induced pluripotent stem cells to identify mechanisms and therapies related to human genetic risk for neurologic a... | Wikipedia - Kristin Baldwin - Summary | 193 | 950 | null |
Section: Career and research. Baldwin was a Ph.D. student and Howard Hughes Medical Institute fellow in the Department of Microbiology and Immunology, Howard Hughes Medical Institute, Stanford University, Stanford, CA, in the laboratory of Mark M. Davis. From 1998 to 2005 she was an associate research scientist / postd... | Wikipedia - Kristin Baldwin - Career and research | 319 | 1,633 | null |
Section: Career and research. Bale joined the faculty at the University of Pennsylvania in 2003. She was the co-director of the Penn Center for the Study of Sex and Gender in Behavioral Health, Director of Research for the BIRCWH Faculty Scholars, and Director of the Neuroscience Center at the School of Veterinary Medi... | Wikipedia - Tracy Bale - Career and research | 333 | 1,799 | null |
Article: Moshe Bar (neuroscientist). Moshe Bar (Hebrew: משה בר; born 1964) is an Israeli cognitive neuroscientist. He is a professor at Bar-Ilan University. He was previously head of the Gonda Multidisciplinary Brain Research Center at Bar-Ilan University and before that director of the Cognitive Neuroscience Laborator... | Wikipedia - Moshe Bar (neuroscientist) - Summary | 164 | 786 | null |
Section: Biography. Bar completed a bachelor's degree in electrical engineering at Ben-Gurion University in 1988. Thereafter, in parallel with military service in the Israeli Air Force, he completed a master's degree in computer science and applied mathematics in 1994 at the Weizmann Institute of Science, where he work... | Wikipedia - Moshe Bar (neuroscientist) - Biography | 281 | 1,479 | null |
Section: Selected publications > Scientific articles. Bar, M. (2004). "Visual objects in context". Nature Reviews Neuroscience. 5: 617–629. doi:10.1038/nrn1476. Bar, M.; Kassam, K.; Ghuman, A.; Boshyan, J.; Dale, A.; Hämäläinen, M.; Marinkovic, K.; Schacter, D.L.; Rosen, B.; Halgren, E. (2006). "Top-down facilitation o... | Wikipedia - Moshe Bar (neuroscientist) - Selected publications > Scientific articles | 226 | 626 | null |
Section: Selected publications > Books. Bar, M., ed. (2011). Predictions in the Brain: Using Our Past to Generate a Future. New York: Oxford University Press. ISBN 978-0195395518. Bar, M.; Bubic, A. (2013). "Top-down Effects in Visual Perception". In Ochsner, K.; Kosslyn, S. (eds.). The Oxford Handbook of Cognitive Neu... | Wikipedia - Moshe Bar (neuroscientist) - Selected publications > Books | 235 | 724 | null |
Article: Robert L. Barchi. Robert Lawrence Barchi (born November 23, 1946) is an American neurologist, physician, and scientist. He was the 20th president of Rutgers University, holding the position from September 1, 2012, to June 30, 2020. Barchi was appointed to the position on April 11, 2012, to succeed Richard L. M... | Wikipedia - Robert L. Barchi - Summary | 154 | 771 | null |
Section: Career. Barchi began as his career an assistant professor in the Department of Biochemistry and Biophysics at the University of Pennsylvania. By 1985, he was the David Mahoney Professor of Neurological Sciences. He served as director of the Mahoney Institute of Neurological Sciences from 1983 to 1996. In 1992,... | Wikipedia - Robert L. Barchi - Career | 335 | 1,783 | null |
Barchi oversaw the formation of Rutgers Biomedical and Health Sciences in 2013 and the entrance of Rutgers University-New Brunswick into the Big Ten Conference a year later. He led the establishment and construction of an honors college at New Brunswick that contributed to a 50-point rise in average SAT scores of incom... | Wikipedia - Robert L. Barchi - Career | 166 | 857 | null |
Article: Chemistry. Chemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes ... | Wikipedia - Chemistry - Summary | 265 | 1,450 | null |
Section: Etymology. The word chemistry comes from a modification during the Renaissance of the word alchemy, which referred to an earlier set of practices that encompassed elements of chemistry, metallurgy, philosophy, astrology, astronomy, mysticism, and medicine. Alchemy is often associated with the quest to turn lea... | Wikipedia - Chemistry - Etymology | 179 | 779 | null |
Section: Modern principles. The current model of atomic structure is the quantum mechanical model. Traditional chemistry starts with the study of elementary particles, atoms, molecules, substances, metals, crystals and other aggregates of matter. Matter can be studied in solid, liquid, gas and plasma states, in isolati... | Wikipedia - Chemistry - Modern principles | 346 | 1,905 | null |
Section: Modern principles > Matter > Atom. The atom is the basic unit of chemistry. It consists of a dense core called the atomic nucleus surrounded by a space occupied by an electron cloud. The nucleus is made up of positively charged protons and uncharged neutrons (together called nucleons), while the electron cloud... | Wikipedia - Chemistry - Modern principles > Matter > Atom | 199 | 930 | null |
Section: Modern principles > Matter > Element. A chemical element is a pure substance which is composed of a single type of atom, characterized by its particular number of protons in the nuclei of its atoms, known as the atomic number and represented by the symbol Z. The mass number is the sum of the number of protons ... | Wikipedia - Chemistry - Modern principles > Matter > Element | 195 | 976 | null |
Section: Modern principles > Matter > Molecule. A molecule is the smallest indivisible portion of a pure chemical substance that has its unique set of chemical properties, that is, its potential to undergo a certain set of chemical reactions with other substances. However, this definition only works well for substances... | Wikipedia - Chemistry - Modern principles > Matter > Molecule | 348 | 1,756 | null |
Identifiable molecules compose familiar substances such as water, air, and many organic compounds like alcohol, sugar, gasoline, and the various pharmaceuticals. However, not all substances or chemical compounds consist of discrete molecules, and indeed most of the solid substances that make up the solid crust, mantle,... | Wikipedia - Chemistry - Modern principles > Matter > Molecule | 233 | 1,217 | null |
Section: Modern principles > Phase. In addition to the specific chemical properties that distinguish different chemical classifications, chemicals can exist in several phases. For the most part, the chemical classifications are independent of these bulk phase classifications; however, some more exotic phases are incomp... | Wikipedia - Chemistry - Modern principles > Phase | 350 | 1,826 | null |
Section: Modern principles > Bonding. Atoms sticking together in molecules or crystals are said to be bonded with one another. A chemical bond may be visualized as the multipole balance between the positive charges in the nuclei and the negative charges oscillating about them. More than simple attraction and repulsion,... | Wikipedia - Chemistry - Modern principles > Bonding | 344 | 1,664 | null |
In a covalent bond, one or more pairs of valence electrons are shared by two atoms: the resulting electrically neutral group of bonded atoms is termed a molecule. Atoms will share valence electrons in such a way as to create a noble gas electron configuration (eight electrons in their outermost shell) for each atom. At... | Wikipedia - Chemistry - Modern principles > Bonding | 198 | 1,035 | null |
Section: Modern principles > Energy. In the context of chemistry, energy is an attribute of a substance as a consequence of its atomic, molecular or aggregate structure. Since a chemical transformation is accompanied by a change in one or more of these kinds of structures, it is invariably accompanied by an increase or... | Wikipedia - Chemistry - Modern principles > Energy | 326 | 1,577 | null |
The activation energy necessary for a chemical reaction to occur can be in the form of heat, light, electricity or mechanical force in the form of ultrasound. A related concept free energy, which also incorporates entropy considerations, is a very useful means for predicting the feasibility of a reaction and determinin... | Wikipedia - Chemistry - Modern principles > Energy | 341 | 1,676 | null |
The transfer of energy from one chemical substance to another depends on the size of energy quanta emitted from one substance. However, heat energy is often transferred more easily from almost any substance to another because the phonons responsible for vibrational and rotational energy levels in a substance have much ... | Wikipedia - Chemistry - Modern principles > Energy | 230 | 1,346 | null |
Section: Modern principles > Reaction. When a chemical substance is transformed as a result of its interaction with another substance or with energy, a chemical reaction is said to have occurred. A chemical reaction is therefore a concept related to the "reaction" of a substance when it comes in close contact with anot... | Wikipedia - Chemistry - Modern principles > Reaction | 346 | 1,852 | null |
Many physical chemists specialize in exploring and proposing the mechanisms of various chemical reactions. Several empirical rules, like the Woodward–Hoffmann rules often come in handy while proposing a mechanism for a chemical reaction. According to the IUPAC gold book, a chemical reaction is "a process that results i... | Wikipedia - Chemistry - Modern principles > Reaction | 159 | 848 | null |
Section: Modern principles > Ions and salts. An ion is a charged species, an atom or a molecule, that has lost or gained one or more electrons. When an atom loses an electron and thus has more protons than electrons, the atom is a positively charged ion or cation. When an atom gains an electron and thus has more electr... | Wikipedia - Chemistry - Modern principles > Ions and salts | 165 | 739 | null |
Section: Modern principles > Acidity and basicity. A substance can often be classified as an acid or a base. There are several different theories which explain acid–base behavior. The simplest is Arrhenius theory, which states that an acid is a substance that produces hydronium ions when it is dissolved in water, and a... | Wikipedia - Chemistry - Modern principles > Acidity and basicity | 350 | 1,663 | null |
Section: Modern principles > Redox. Redox (reduction-oxidation) reactions include all chemical reactions in which atoms have their oxidation state changed by either gaining electrons (reduction) or losing electrons (oxidation). Substances that have the ability to oxidize other substances are said to be oxidative and ar... | Wikipedia - Chemistry - Modern principles > Redox | 198 | 973 | null |
Section: History. The history of chemistry spans a period from the ancient past to the present. Since several millennia BC, civilizations were using technologies that would eventually form the basis of the various branches of chemistry. Examples include extracting metals from ores, making pottery and glazes, fermenting... | Wikipedia - Chemistry - History | 301 | 1,600 | null |
Section: History > Definition. The definition of chemistry has changed over time, as new discoveries and theories add to the functionality of the science. The term "chymistry", in the view of noted scientist Robert Boyle in 1661, meant the subject of the material principles of mixed bodies. In 1663, the chemist Christo... | Wikipedia - Chemistry - History > Definition | 260 | 1,279 | null |
Section: History > Background. Early civilizations, such as the Egyptians, Babylonians, and Indians, amassed practical knowledge concerning the arts of metallurgy, pottery and dyes, but did not develop a systematic theory. A basic chemical hypothesis first emerged in Classical Greece with the theory of four elements as... | Wikipedia - Chemistry - History > Background | 334 | 1,606 | null |
In the Hellenistic world the art of alchemy first proliferated, mingling magic and occultism into the study of natural substances with the ultimate goal of transmuting elements into gold and discovering the elixir of eternal life. Work, particularly the development of distillation, continued in the early Byzantine peri... | Wikipedia - Chemistry - History > Background | 350 | 1,653 | null |
Improvements of the refining of ores and their extractions to smelt metals was widely used source of information for early chemists in the 16th century, among them Georg Agricola (1494–1555), who published his major work De re metallica in 1556. His work, describing highly developed and complex processes of mining meta... | Wikipedia - Chemistry - History > Background | 305 | 1,536 | null |
In the following decades, many important discoveries were made, such as the nature of 'air' which was discovered to be composed of many different gases. The Scottish chemist Joseph Black and the Flemish Jan Baptist van Helmont discovered carbon dioxide, or what Black called 'fixed air' in 1754; Henry Cavendish discover... | Wikipedia - Chemistry - History > Background | 339 | 1,711 | null |
J.A.R. Newlands devised an early table of elements, which was then developed into the modern periodic table of elements in the 1860s by Dmitri Mendeleev and independently by several other scientists including Julius Lothar Meyer. The inert gases, later called the noble gases were discovered by William Ramsay in collabo... | Wikipedia - Chemistry - History > Background | 344 | 1,763 | null |
Section: Practice > Subdisciplines. Chemistry is typically divided into several major sub-disciplines. There are also several main cross-disciplinary and more specialized fields of chemistry. Analytical chemistry is the analysis of material samples to gain an understanding of their chemical composition and structure. A... | Wikipedia - Chemistry - Practice > Subdisciplines | 343 | 1,935 | null |
Nuclear chemistry is the study of how subatomic particles come together and make nuclei. Modern transmutation is a large component of nuclear chemistry, and the table of nuclides is an important result and tool for this field. In addition to medical applications, nuclear chemistry encompasses nuclear engineering which ... | Wikipedia - Chemistry - Practice > Subdisciplines | 347 | 2,058 | null |
Article: Actinide chemistry. Actinide chemistry (or actinoid chemistry) is one of the main branches of nuclear chemistry that investigates the processes and molecular systems of the actinides. The actinides derive their name from the group 3 element actinium. The informal chemical symbol An is used in general discussio... | Wikipedia - Actinide chemistry - Summary | 176 | 793 | null |
Section: Main branches > Nanotechnology and supramolecular chemistry of actinides. The possibility of using unique properties of lanthanides in the nanotechnology is demonstrated. The origination of linear and nonlinear optical properties of lanthanide compounds with phthalocyanines, porphyrins, naphthalocyanines, and ... | Wikipedia - Actinide chemistry - Main branches > Nanotechnology and supramolecular chemistry of actinides | 274 | 1,325 | null |
Section: Main branches > Biological and environmental chemistry of actinides. Generally, ingested insoluble actinide compounds such as high-fired uranium dioxide and mixed oxide (MOX) fuel will pass through the digestive system with little effect since they cannot dissolve and be absorbed by the body. Inhaled actinide ... | Wikipedia - Actinide chemistry - Main branches > Biological and environmental chemistry of actinides | 348 | 1,660 | null |
Significant concentrations of uranium occur in some substances such as phosphate rock deposits, and minerals such as lignite, and monazite sands in uranium-rich ores (it is recovered commercially from these sources). Seawater contains about 3.3 parts per billion of uranium by weight as uranium(VI) forms soluble carbona... | Wikipedia - Actinide chemistry - Main branches > Biological and environmental chemistry of actinides | 198 | 890 | null |
Section: PUREX. The PUREX process is a liquid–liquid extraction ion-exchange method used to reprocess spent nuclear fuel, in order to extract primarily uranium and plutonium, independent of each other, from the other constituents. The current method of choice is to use the PUREX liquid–liquid extraction process which u... | Wikipedia - Actinide chemistry - PUREX | 293 | 1,274 | null |
Emulsions are often referred to as third phases in the solvent extraction community. An organic solvent composed of 30% tributyl phosphate (TBP) in a hydrocarbon solvent, such as kerosene, is used to extract the uranium as UO2(NO3)2·2TBP complexes, and plutonium as similar complexes, from other fission products, which ... | Wikipedia - Actinide chemistry - PUREX | 230 | 976 | null |
Article: Allotropy. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements. Allotropes are different structural modifications... | Wikipedia - Allotropy - Summary | 304 | 1,302 | null |
Section: History. The concept of allotropy was originally proposed in 1840 by the Swedish scientist Baron Jöns Jakob Berzelius (1779–1848). The term is derived from Greek άλλοτροπἱα (allotropia) 'variability, changeableness'. After the acceptance of Avogadro's hypothesis in 1860, it was understood that elements could e... | Wikipedia - Allotropy - History | 221 | 928 | null |
Section: Differences in properties of an element's allotropes. Allotropes are different structural forms of the same element and can exhibit quite different physical properties and chemical behaviours. The change between allotropic forms is triggered by the same forces that affect other structures, i.e., pressure, ligh... | Wikipedia - Allotropy - Differences in properties of an element's allotropes | 187 | 813 | null |
Section: List of allotropes > Metals. Among the metallic elements that occur in nature in significant quantities (56 up to U, without Tc and Pm), almost half (27) are allotropic at ambient pressure: Li, Be, Na, Ca, Ti, Mn, Fe, Co, Sr, Y, Zr, Sn, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Yb, Hf, Tl, Th, Pa and U. Some phase trans... | Wikipedia - Allotropy - List of allotropes > Metals | 196 | 687 | null |
Section: List of allotropes > Metals > Lanthanides and actinides. Cerium, samarium, dysprosium and ytterbium have three allotropes. Praseodymium, neodymium, gadolinium and terbium have two allotropes. Plutonium has six distinct solid allotropes under "normal" pressures. Their densities vary within a ratio of some 4:3, ... | Wikipedia - Allotropy - List of allotropes > Metals > Lanthanides and actinides | 176 | 623 | null |
Section: Nanoallotropes. In 2017, the concept of nanoallotropy was proposed. Nanoallotropes, or allotropes of nanomaterials, are nanoporous materials that have the same chemical composition (e.g., Au), but differ in their architecture at the nanoscale (that is, on a scale 10 to 100 times the dimensions of individual at... | Wikipedia - Allotropy - Nanoallotropes | 157 | 686 | null |
Article: Alloy. An alloy is a mixture of chemical elements of which in most cases at least one is a metallic element, although it is also sometimes used for mixtures of elements; herein only metallic alloys are described. Metallic alloys often have properties that differ from those of the pure elements from which they ... | Wikipedia - Alloy - Summary | 305 | 1,537 | null |
They can be further classified as homogeneous (consisting of a single phase), or heterogeneous (consisting of two or more phases) or intermetallic. An alloy may be a solid solution of metal elements (a single phase, where all metallic grains (crystals) are of the same composition) or a mixture of metallic phases (two o... | Wikipedia - Alloy - Summary | 202 | 912 | null |
Section: Characteristics. An alloy is a mixture of chemical elements, which forms an impure substance (admixture) that retains the characteristics of a metal. An alloy is distinct from an impure metal in that, with an alloy, the added elements are well controlled to produce desirable properties, while impure metals suc... | Wikipedia - Alloy - Characteristics | 336 | 1,673 | null |
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