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Gold Nanoparticle
Colloidal gold is a sol or colloidal suspension of nanoparticles of gold in a fluid, usually water. The colloid is usually either wine-red coloured (for spherical particles less than 100 nm) or blue/purple (for larger spherical particles or nanorods). Due to their optical, electronic, and molecular-recognition properties, gold nanoparticles are the subject of substantial research, with many potential or promised applications in a wide variety of areas, including electron microscopy, electronics, nanotechnology, materials science, and biomedicine. The properties of colloidal gold nanoparticles, and thus their potential applications, depend strongly upon their size and shape. For example, rodlike particles have both a transverse and longitudinal absorption peak, and anisotropy of the shape affects their self-assembly. History Used since ancient times as a method of staining glass colloidal gold was used in the 4th-century Lycurgus Cup, which changes color depending on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold255
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal in a pure form. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental (native state), as nuggets or grains, in rocks, veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to most acids, though it does dissolve in aqua regia (a mixture of nitric acid and hydrochloric acid), forming a soluble tetrachloroaurate anion. Gold i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stained Glass
Stained glass is coloured glass as a material or works created from it. Throughout its thousand-year history, the term has been applied almost exclusively to the windows of churches and other significant religious buildings. Although traditionally made in flat panels and used as windows, the creations of modern stained glass artists also include three-dimensional structures and sculpture. Modern vernacular usage has often extended the term "stained glass" to include domestic lead light and '' objets d'art'' created from foil glasswork exemplified in the famous lamps of Louis Comfort Tiffany. As a material ''stained glass'' is glass that has been coloured by adding metallic salts during its manufacture, and usually then further decorating it in various ways. The coloured glass is crafted into ''stained glass windows'' in which small pieces of glass are arranged to form patterns or pictures, held together (traditionally) by strips of lead and supported by a rigid frame. Pai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Scattering
Scattering is a term used in physics to describe a wide range of physical processes where moving particles or radiation of some form, such as light or sound, are forced to deviate from a straight trajectory by localized non-uniformities (including particles and radiation) in the medium through which they pass. In conventional use, this also includes deviation of reflected radiation from the angle predicted by the law of reflection. Reflections of radiation that undergo scattering are often called ''diffuse reflections'' and unscattered reflections are called '' specular'' (mirror-like) reflections. Originally, the term was confined to light scattering (going back at least as far as Isaac Newton in the 17th century). As more "ray"-like phenomena were discovered, the idea of scattering was extended to them, so that William Herschel could refer to the scattering of "heat rays" (not then recognized as electromagnetic in nature) in 1800. John Tyndall, a pioneer in light scattering rese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Redox
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate. Elemental phosphorus was first isolated as white phosphorus in 1669. White phosphorus emits a faint glow when exposed to oxygen – hence the name, taken from Greek mythology, meaning 'light-bearer' (Latin ), referring to the "Morning Star", the planet Venus. The term '' phosphorescence'', meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus — a process now called che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Institution
The Royal Institution of Great Britain (often the Royal Institution, Ri or RI) is an organisation for scientific education and research, based in the City of Westminster. It was founded in 1799 by the leading British scientists of the age, including Henry Cavendish and its first president, George Finch. Its foundational principles were diffusing the knowledge of, and facilitating the general introduction of useful mechanical inventions and improvements, as well as enhancing the application of science to the common purposes of life (including through teaching, courses of philosophical lectures, and experiments). Much of the Institution's initial funding and the initial proposal for its founding were given by the Society for Bettering the Conditions and Improving the Comforts of the Poor, under the guidance of philanthropist Sir Thomas Bernard and American-born British scientist Sir Benjamin Thompson, Count Rumford. Since its founding it has been based at 21 Albemarle Street ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Faraday
Michael Faraday (; 22 September 1791 – 25 August 1867) was an English scientist who contributed to the study of electromagnetism and electrochemistry. His main discoveries include the principles underlying electromagnetic induction, diamagnetism and electrolysis. Although Faraday received little formal education, he was one of the most influential scientists in history. It was by his research on the magnetic field around a conductor carrying a direct current that Faraday established the concept of the electromagnetic field in physics. Faraday also established that magnetism could affect rays of light and that there was an underlying relationship between the two phenomena.. the 1911 Encyclopædia Britannica. He similarly discovered the principles of electromagnetic induction, diamagnetism, and the laws of electrolysis. His inventions of electromagnetic rotary devices formed the foundation of electric motor technology, and it was largely due to his efforts ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Herschel
Sir John Frederick William Herschel, 1st Baronet (; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor, 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. Early life and work on astronomy Herschel was born in Slough, Buckinghamshire, the son of Mary Baldwin and astronomer William Herschel. He was the nephew of astronomer Caroline Herschel. He studied shortly at Eton Colle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Von Löwenstern-Kunckel
Johann Kunckel, awarded Swedish nobility in 1693 under the Swedish name von Löwenstern-Kunckel and the German version of the name Kunckel von Löwenstern (1630 - prob. 20 March 1703), German chemist, was born in 1630 (or 1638), near Rendsburg, his father being alchemist to the court of Holstein. He became chemist and apothecary to the dukes of Lauenburg, and then to the Elector of Saxony, Johann Georg II, who put him in charge of the royal laboratory at Dresden. Intrigues engineered against him caused him to resign this position in 1677, and for a time he lectured on chemistry at Annaberg and Wittenberg. Invited to Berlin by Frederick William, in 1679 he became director of the laboratory and glass works of Brandenburg. In 1688 the king of Sweden, Charles XI, brought him to Stockholm, ennobling him under the name ''von Löwenstern-Kunckel'' in 1693 and making him a member of the Bergskollegium, the Board of Mines. He died probably on 20 March 1703 near Stockholm (other sources ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nicholas Culpeper
Nicholas Culpeper (18 October 1616 – 10 January 1654) was an English botanist, herbalist, physician and astrologer.Patrick Curry: "Culpeper, Nicholas (1616–1654)", ''Oxford Dictionary of National Biography'' (Oxford, UK: OUP, 2004) His book ''The English Physician'' (1652, later ''Complete Herbal'', 1653 ff.) is a source of pharmaceutical and herbal lore of the time, and ''Astrological Judgement of Diseases from the Decumbiture of the Sick'' (1655) one of the most detailed works on medical astrology in Early Modern Europe. Culpeper catalogued hundreds of outdoor medicinal herbs. He scolded contemporaries for some of the methods they used in herbal medicine: "This not being pleasing, and less profitable to me, I consulted with my two brothers, and , and took a voyage to visit my mother , by whose advice, together with the help of , I at last obtained my desire; and, being warned by , a stranger in our days, to publish it to the world, I have done it." Culpeper came from a l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drinking Water
Drinking water is water that is used in drink or food preparation; potable water is water that is safe to be used as drinking water. The amount of drinking water required to maintain good health varies, and depends on physical activity level, age, health-related issues, and environmental conditions. This 2004 article focuses on the USA context and uses data collected from the US military. Recent work showed that the most important driver of water turnover which is closely linked to water requirements is energy expenditure. For those who work in a hot climate, up to a day may be required. Typically in developed countries, tap water meets drinking water quality standards, even though only a small proportion is actually consumed or used in food preparation. Other typical uses for tap water include washing, toilets, and irrigation. Greywater may also be used for toilets or irrigation. Its use for irrigation however may be associated with risks. Water may also be unacceptable d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Francis Anthony
Francis Anthony (16 April 1550 – 26 May 1623) was a 16th-century physician and chemist. His father, Derrick Anthony, was a goldsmith in London, employed in the jewel office of Queen Elizabeth. He attended the University of Cambridge, receiving a master of arts degree in 1574. He studied the theory and practice of chemistry, leaving Cambridge at the age of 40. In 1598, he sent abroad his first treatise concerning the excellency of a medicine drawn from gold. "Aurum Potabile" He commenced a medical practice in London without a Licence from the college of Physicians, and after six months was called before the president of the college of Physicians. He was interdicted practice; for disregarding this injunction, he was fined five pounds and committed to prison, whence he was released by a warrant of the lord chief justice. The college however got him recommitted and Anthony submitted. Being again prosecuted for the same offence and refusing to pay a heavy fine, he was kept in pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
