Chemist in the context of "Joseph Priestley"

Sir John Frederick William Herschel, 1st Baronet KH FRS (/ˈhɜːrʃəl, ˈhɛər-/; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor and experimental photographer who invented the blueprint and did botanical work.

Herschel originated the use of the Julian day system in astronomy. He named seven moons of Saturn and four moons of Uranus – the seventh planet, discovered by his father Sir William Herschel. He made many contributions to the science of photography, and investigated colour blindness and the chemical power of ultraviolet rays. His Preliminary Discourse (1831), which advocated an inductive approach to scientific experiment and theory-building, was an important contribution to the philosophy of science.

Alexander Porfiryevich Borodin (12 November 1833 – 27 February 1887) was a Russian Romantic composer and chemist of Georgian–Russian parentage. He was one of the prominent 19th-century composers known as "The Five", a group dedicated to producing a "uniquely Russian" kind of classical music. Borodin is known best for his symphonies, his two string quartets, the symphonic poem In the Steppes of Central Asia and his opera Prince Igor.

A doctor and chemist by profession and training, Borodin made important early contributions to organic chemistry. Although he is presently known better as a composer, he regarded medicine and science as his primary occupations, only practising music and composition in his spare time or when he was ill. As a chemist, Borodin is known best for his work concerning organic synthesis, including being among the first chemists to demonstrate nucleophilic substitution, as well as being the co-discoverer of the aldol reaction. Borodin was a promoter of education in Russia and founded the School of Medicine for Women in Saint Petersburg, where he taught until 1885.

A gamma ray, also known as gamma radiation (symbol γ), is a penetrating form of electromagnetic radiation arising from high-energy interactions like the radioactive decay of atomic nuclei or astronomical events like solar flares. It consists of the shortest wavelength electromagnetic waves, typically shorter than those of X-rays. With frequencies above 30 exahertz (3×10 Hz) and wavelengths less than 10 picometers (1×10 m), gamma ray photons have the highest photon energy of any form of electromagnetic radiation. Paul Villard, a French chemist and physicist, discovered gamma radiation in 1900 while studying radiation emitted by radium. In 1903, Ernest Rutherford named this radiation gamma rays based on their relatively strong penetration of matter; in 1900, he had already named two less penetrating types of decay radiation (discovered by Henri Becquerel) alpha rays and beta rays in ascending order of penetrating power.

Gamma rays from radioactive decay are in the energy range from a few kiloelectronvolts (keV) to approximately 8 megaelectronvolts (MeV), corresponding to the typical energy levels in nuclei with reasonably long lifetimes. The energy spectrum of gamma rays can be used to identify the decaying radionuclides using gamma spectroscopy. Very-high-energy gamma rays in the 100–1000 teraelectronvolt (TeV) range have been observed from astronomical sources such as the Cygnus X-3 microquasar.

Organic compounds are a subclass of chemical compounds of carbon. Little consensus exists among chemists on the exact definition of organic compound; the only universally accepted definition is the quasi-tautological "organic compounds are the subject matter of organic chemistry".

Generally, any large chemical compound containing a carbon–hydrogen or carbon–carbon bond is accepted as an organic compound. Thus alkanes (e.g. ethane, CH₃−CH₃) and their derivatives are typically considered organic. For historical and disciplinary reasons, small molecules containing carbon are generally not accepted: cyanide ion (CN), hydrogen cyanide (HCN), chloroformic acid (ClCO₂H), carbon dioxide (CO₂), and carbonate ion (CO2−3) may all be excluded.

Louis Pasteur ForMemRS (/ˈluːi pæˈstɜːr/, French: [lwi pastœʁ] ; 27 December 1822 – 28 September 1895) was a French chemist, pharmacist, and microbiologist renowned for his discoveries of the principles of vaccination, microbial fermentation, and pasteurization, the last of which was named after him. His research in chemistry led to remarkable breakthroughs in the understanding of the causes and preventions of diseases, which laid down the foundations of hygiene, public health and much of modern medicine. Pasteur's works are credited with saving millions of lives through the developments of vaccines for rabies and anthrax. He is regarded as one of the founders of modern bacteriology and has been honored as the "father of bacteriology" and the "father of microbiology" (together with Robert Koch; the latter epithet also attributed to Antonie van Leeuwenhoek).

Pasteur was responsible for disproving the doctrine of spontaneous generation. Under the auspices of the French Academy of Sciences, his experiment demonstrated that in sterilized and sealed flasks, nothing ever developed; conversely, in sterilized but open flasks, microorganisms could grow. For this experiment, the academy awarded him the Alhumbert Prize carrying 2,500 francs in 1862.

Rosalind Elsie Franklin (25 July 1920 – 16 April 1958) was an English chemist and X-ray crystallographer. Her work was central to the understanding of the molecular structures of DNA (deoxyribonucleic acid), RNA (ribonucleic acid), viruses, coal, and graphite. Although her works on coal and viruses were appreciated in her lifetime, Franklin's contributions to the discovery of the structure of DNA were largely unrecognised during her life, for which Franklin has been variously referred to as the "wronged heroine", the "dark lady of DNA", the "forgotten heroine", a "feminist icon", and the "Sylvia Plath of molecular biology".

Franklin graduated in 1941 with a degree in natural sciences from Newnham College, Cambridge, and then enrolled for a PhD in physical chemistry under Ronald George Wreyford Norrish, the 1920 Chair of Physical Chemistry at the University of Cambridge. Disappointed by Norrish's lack of enthusiasm, she took up a research position under the British Coal Utilisation Research Association (BCURA) in 1942. The research on coal helped Franklin earn a PhD from Cambridge in 1945. Moving to Paris in 1947 as a chercheur (postdoctoral researcher) under Jacques Mering at the Laboratoire Central des Services Chimiques de l'État, she became an accomplished X-ray crystallographer. After joining King's College London in 1951 as a research associate, Franklin discovered some key properties of DNA, which eventually facilitated the correct description of the double helix structure of DNA. Owing to disagreement with her director, John Randall, and her colleague Maurice Wilkins, Franklin was compelled to move to Birkbeck College in 1953.

Abū al-Qāsim Khalaf ibn al-'Abbās al-Zahrāwī al-Ansari (c. 936–1013), popularly known as al-Zahrawi, Latinised as Albucasis or Abulcasis (from Arabic Abū al-Qāsim), was an Arab physician, surgeon and chemist from al-Andalus. He is considered one of the greatest surgeons of the Middle Ages.

Al-Zahrawi's principal work is the Kitab al-Tasrif, a thirty-volume encyclopedia of medical practices. The surgery chapter of this work was later translated into Latin, attaining popularity and becoming the standard textbook in Europe for the next five hundred years. Al-Zahrawi's pioneering contributions to the field of surgical procedures and instruments had an enormous impact in the East and West well into the modern period, where some of his discoveries are still applied in medicine to this day. He pioneered the use of catgut for internal stitches, and his surgical instruments are still used today to treat people.

Tracy Caldwell Dyson (born Tracy Ellen Caldwell; August 14, 1969) is an American chemist and NASA astronaut. She was a mission specialist on Space Shuttle Endeavour flight STS-118 in August 2007 and has participated in two long-duration missions to the International Space Station, Expedition 23 and 24 from April to September 2010 and Expedition 70 and 71 from March to September 2024. She has completed four spacewalks, logging nearly 24 hours of extravehicular activity.