|
Joseph Black
Joseph Black (16 April 1728 – 6 December 1799) was a British physicist and chemist, known for his discoveries of magnesium, latent heat, specific heat, and carbon dioxide. He was Professor of Anatomy and Chemistry at the University of Glasgow for 10 years from 1756, and then Professor of Medicine and Chemistry at the University of Edinburgh from 1766, teaching and lecturing there for more than 30 years. The chemistry buildings at both the University of Edinburgh and the University of Glasgow are named after Black. Early life and education Black was born "on the banks of the river Garonne" in Bordeaux, France, the sixth of the 12 children of Margaret Gordon (''d''. 1747) and John Black. His mother was from an Aberdeenshire family that had connections with the wine business and his father was from Belfast, Ireland, and worked as a factor in the wine trade. He was educated at home until the age of 12, after which he attended grammar school in Belfast. In 1746, at the age of 18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mezzotint
Mezzotint is a monochrome printmaking process of the intaglio (printmaking), intaglio family. It was the first printing process that yielded half-tones without using line- or dot-based techniques like hatching, cross-hatching or stipple. Mezzotint achieves tonality by roughening a metal plate with thousands of little dots made by a metal tool with small teeth, called a "rocker". In printing, the tiny pits in the plate retain the ink when the face of the plate is wiped clean. This technique can achieve a high level of quality and richness in the print, and produce a furniture print which is large and bold enough to be framed and hung effectively in a room. Mezzotint is often combined with other intaglio techniques, usually etching and engraving, including stipple engraving. The process was especially widely used in England from the eighteenth century, and in France was called ''la manière anglais'' (“the English manner”). Until the 20th century it has mostly been used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 chemical compound, compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during chemical reaction, reactions with other chemical substance, substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology. It is sometimes called the central science because it provides a foundation for understanding both Basic research, basic and Applied science, applied scientific disciplines at a fundamental level. For example, chemistry explains aspects of plant growth (botany), the formation of igneous rocks (geology), how atmospheric ozone is formed and how environmental pollutants are degraded (ecology), the prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Analytical Balance
An analytical balance (or chemical ''balance'') is a class of balance designed to measure small mass in the sub-milligram range. The measuring pan of an analytical balance (0.1 mg resolution or better) is inside a transparent enclosure with doors so that dust does not collect and so any air currents in the room do not affect the balance's operation. This enclosure is often called a draft shield. The use of a mechanically vented balance safety enclosure, which has uniquely designed acrylic airfoils, allows a smooth turbulence-free airflow that prevents balance fluctuation and the measure of mass down to 1 μg without fluctuations or loss of product. Also, the sample must be at room temperature to prevent natural convection from forming air currents inside the enclosure from causing an error in reading. Single pan mechanical substitution balance is a method of maintaining consistent response throughout the useful capacity of the balance. This is achieved by maintaining a constan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatic Chemistry
In the history of science, pneumatic chemistry is an area of scientific research of the seventeenth, eighteenth, and early nineteenth centuries. Important goals of this work were the understanding of the physical properties of gases and how they relate to chemical reactions and, ultimately, the composition of matter. The rise of phlogiston theory, and its replacement by a new theory after the discovery of oxygen as a gaseous component of the Earth atmosphere and a chemical reagent participating in the combustion reactions, were addressed in the era of pneumatic chemistry. Air as a reagent In the eighteenth century, as the field of chemistry was evolving from alchemy, a field of the natural philosophy was created around the idea of air as a reagent. Before this, air was primarily considered a static substance that would not react and simply existed. However, as Lavoisier and several other pneumatic chemists would insist, the air was indeed dynamic, and would not only be influence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Principle (chemistry)
Principle, in chemistry, refers to a historical concept of the constituents of a substance, specifically those that produce a certain quality or effect in the substance, such as a ''bitter principle'', which is any one of the numerous compounds having a bitter taste. The idea of chemical principles developed out of the classical elements. Paracelsus identified the '' tria prima'' as principles in his approach to medicine. In his book ''The Sceptical Chymist'' of 1661, Robert Boyle criticized the traditional understanding of the composition of materials and initiated the modern understanding of chemical elements. Nevertheless, the concept of chemical principles continued to be used. Georg Ernst Stahl published ''Philosophical Principles of Universal Chemistry'' in 1730 as an early effort to distinguish between mixtures and compounds. He writes, "the ''simple'' are ''Principles'', or the first material causes of ''Mixts'';..." Georg Ernst Stahl (1730Philosophical Principles of Unive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Carbonate
Magnesium carbonate, (archaic name magnesia alba), is an inorganic salt that is a colourless or white solid. Several hydrated and Base (chemistry), basic forms of magnesium carbonate also exist as minerals. Forms The most common magnesium carbonate forms are the anhydrous salt called magnesite (), and the di, tri, and pentahydrates known as barringtonite (), nesquehonite (), and lansfordite (), respectively. Some basic forms such as artinite (), hydromagnesite (), and dypingite () also occur as minerals. All of those minerals are colourless or white. Magnesite consists of colourless or white trigonal crystals. The anhydrous salt is practically insoluble in water, acetone, and ammonia. All forms of magnesium carbonate react with acids. Magnesite crystallizes in the calcite structure wherein magnesium, is Coordination geometry#Crystallography usage, surrounded by six oxygen atoms. The dihydrate has a triclinic structure, while the trihydrate has a monoclinic structure. Refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kidney Stones
Kidney stone disease (known as nephrolithiasis, renal calculus disease, or urolithiasis) is a crystallopathy and occurs when there are too many minerals in the urine and not enough liquid or hydration. This imbalance causes tiny pieces of crystal to aggregate and form hard masses, or calculi (stones) in the upper urinary tract. Because renal calculi typically form in the kidney, if small enough, they are able to leave the urinary tract via the urine stream. A small calculus may pass without causing symptoms. However, if a stone grows to more than , it can cause blockage of the ureter, resulting in extremely sharp and severe pain ( renal colic) in the lower back that often radiates downward to the groin. A calculus may also result in blood in the urine, vomiting (due to severe pain), or painful urination. About half of all people who have had a kidney stone are likely to develop another within ten years. ''Renal'' is Latin for "kidney", while "nephro" is the Greek equival ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wine
Wine is an alcoholic drink made from Fermentation in winemaking, fermented fruit. Yeast in winemaking, Yeast consumes the sugar in the fruit and converts it to ethanol and carbon dioxide, releasing heat in the process. Wine is most often made from grapes, and the term "wine" generally refers to grape wine when used without any qualification. Even so, wine can be made fruit wine, from a variety of fruit crops, including plum, cherry, pomegranate, blueberry, Ribes, currant, and Sambucus, elderberry. Different varieties of grapes and Strain (biology), strains of yeasts are major factors in different styles of wine. These differences result from the complex interactions between the Biochemistry, biochemical development of the grape, the reactions involved in fermentation, the grape's growing environment (terroir), and the wine production process. Many countries enact legal appellations intended to define styles and qualities of wine. These typically restrict the geographical origin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Factor (agent)
A factor is a type of trader who receives and sells goods on commission, called factorage. A factor is a mercantile fiduciary transacting business that operates in their own name and does not disclose their principal. A factor differs from a commission merchant in that a factor takes possession of goods (or documents of title representing goods, such as a bill of lading) on consignment, but a commission merchant sells goods not in their possession on the basis of samples. Most modern factor business is in the textile field, but factors are also used to a great extent in the shoe, furniture, hardware, and other industries. The number of trade areas in which factors operate has increased. In the United Kingdom, most factors fall within the definition of a mercantile agent under the Factors Act 1889 ( 52 & 53 Vict. c. 45), and therefore have the powers of such. A factor has a possessory lien over the consigned goods that covers any claims against the principal arising out of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belfast
Belfast (, , , ; from ) is the capital city and principal port of Northern Ireland, standing on the banks of the River Lagan and connected to the open sea through Belfast Lough and the North Channel (Great Britain and Ireland), North Channel. It is the second-largest city in Ireland (after Dublin), with an estimated population of in , and a Belfast metropolitan area, metropolitan area population of 671,559. First chartered as an English settlement in 1613, the town's early growth was driven by an influx of Scottish people, Scottish Presbyterian Church in Ireland, Presbyterians. Their descendants' disaffection with Kingdom of Ireland, Ireland's Protestant Ascendancy, Anglican establishment contributed to the Irish Rebellion of 1798, rebellion of 1798, and to the Acts of Union 1800, union with Kingdom of Great Britain, Great Britain in 1800—later regarded as a key to the town's industrial transformation. When granted City status in the United Kingdom#Northern Ireland, city s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aberdeenshire
Aberdeenshire (; ) is one of the 32 Subdivisions of Scotland#council areas of Scotland, council areas of Scotland. It takes its name from the Shires of Scotland, historic county of Aberdeenshire (historic), Aberdeenshire, which had substantially different boundaries. The Aberdeenshire Council area includes all of the areas of the historic counties of Aberdeenshire and Kincardineshire except the area making up Aberdeen City Council area, as well as part of Banffshire. The historic county boundaries are still officially used for a few purposes, namely land registration and Lieutenancy areas of Scotland, lieutenancy. Aberdeenshire Council is headquartered at Woodhill House in Aberdeen, making it the only Scottish council whose headquarters are located outside its jurisdiction. Aberdeen itself forms a different council area (Aberdeen City). Aberdeenshire borders onto Angus, Scotland, Angus and Perth and Kinross to the south, Highland (council area), Highland and Moray to the west a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
