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History Of Nanotechnology
The history of nanotechnology traces the development of the concepts and experimental work falling under the broad category of nanotechnology. Although nanotechnology is a relatively recent development in scientific research, the development of its central concepts happened over a longer period of time. The emergence of nanotechnology in the 1980s was caused by the convergence of experimental advances such as the invention of the scanning tunneling microscope in 1981 and the discovery of fullerenes in 1985, with the elucidation and popularization of a conceptual framework for the goals of nanotechnology beginning with the 1986 publication of the book ''Engines of Creation''. The field was subject to growing public awareness and controversy in the early 2000s, with prominent debates about both its potential implications as well as the feasibility of the applications envisioned by advocates of molecular nanotechnology, and with governments moving to promote and fund research in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanotechnology
Nanotechnology, also shortened to nanotech, is the use of matter on an atomic, molecular, and supramolecular scale for industrial purposes. The earliest, widespread description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology. A more generalized description of nanotechnology was subsequently established by the National Nanotechnology Initiative, which defined nanotechnology as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). This definition reflects the fact that quantum mechanical effects are important at this quantum-realm scale, and so the definition shifted from a particular technological goal to a research category inclusive of all types of research and technologies that deal with the special properties of matter which occur below the given size threshold. It is therefore common to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lusterware
Lustreware or lusterware (respectively the spellings for British English and American English) is a type of pottery or porcelain with a metallic glaze that gives the effect of iridescence. It is produced by metallic oxides in an overglaze finish, which is given a second firing at a lower temperature in a "muffle kiln", or a reduction kiln, excluding oxygen. The technique of lustreware on pottery was first developed in Mesopotamia (modern Iraq) in the early 9th century. Initially mostly decorated with geometric patterns, by the 10th century an Iraqi style with the design dominated by one or two large figures developed. After the Fatimid conquest of Egypt in 969, it became a great centre of lustreware production until the Fatimid Caliphate fell in 1171, soon after the potter's quarter of the capital Fustat (Cairo) was burned in 1169. It is thought that the Fustat potters dispersed to both Syria and Persia, and lustreware appears there about this time; later the devastating conq ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clay
Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay particles, but become hard, brittle and non–plastic upon drying or firing. Most pure clay minerals are white or light-coloured, but natural clays show a variety of colours from impurities, such as a reddish or brownish colour from small amounts of iron oxide. Clay is the oldest known ceramic material. Prehistoric humans discovered the useful properties of clay and used it for making pottery. Some of the earliest pottery shards have been dated to around 14,000 BC, and clay tablets were the first known writing medium. Clay is used in many modern industrial processes, such as paper making, cement production, and chemical filtering. Between one-half and two-thirds of the world's population live or work in buildings made with clay, often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ochre
Ochre ( ; , ), or ocher in American English, is a natural clay earth pigment, a mixture of ferric oxide and varying amounts of clay and sand. It ranges in colour from yellow to deep orange or brown. It is also the name of the colours produced by this pigment, especially a light brownish-yellow. A variant of ochre containing a large amount of hematite, or dehydrated iron oxide, has a reddish tint known as "red ochre" (or, in some dialects, ruddle). The word ochre also describes clays coloured with iron oxide derived during the extraction of tin and copper. Earth pigments Ochre is a family of earth pigments, which includes yellow ochre, red ochre, purple ochre, sienna, and umber. The major ingredient of all the ochres is iron(III) oxide-hydroxide, known as limonite, which gives them a yellow colour. * Yellow ochre, , is a hydrated iron hydroxide (limonite) also called gold ochre. * Red ochre, , takes its reddish colour from the mineral hematite, which is an anhydrous iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vinegar
Vinegar is an aqueous solution of acetic acid and trace compounds that may include flavorings. Vinegar typically contains 5–8% acetic acid by volume. Usually, the acetic acid is produced by a double fermentation, converting simple sugars to ethanol using yeast, and ethanol to acetic acid by acetic acid bacteria. Many types of vinegar are available, depending on source materials. It is now mainly used in the culinary arts as a flavorful, acidic cooking ingredient, or in pickling. Various types are used as condiments or garnishes, including balsamic vinegar and malt vinegar. As the most easily manufactured mild acid, it has a wide variety of industrial and domestic uses, including use as a household cleaner. Etymology The word "vinegar" arrived in Middle English from Old French (''vyn egre''; sour wine), which in turn derives from Latin: ''vinum'' (wine) + ''acer'' (sour). Chemistry The conversion of ethanol (CH3CH2OH) and oxygen (O2) to acetic acid (CH3COOH) takes plac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry (the measurable relationship between reactants and chemical equations of a equation or reaction) Oxides are extraordinarily diverse in terms of stoichiometries and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salt (chemistry)
In chemistry, a salt is a chemical compound consisting of an ionic assembly of positively charged cations and negatively charged anions, which results in a compound with no net electric charge. A common example is table salt, with positively charged sodium ions and negatively charged chloride ions. The component ions in a salt compound can be either inorganic, such as chloride (Cl−), or organic, such as acetate (). Each ion can be either monatomic, such as fluoride (F−), or polyatomic, such as sulfate (). Types of salt Salts can be classified in a variety of ways. Salts that produce hydroxide ions when dissolved in water are called ''alkali salts'' and salts that produce hydrogen ions when dissolved in water are called ''acid salts''. ''Neutral salts'' are those salts that are neither acidic nor basic. Zwitterions contain an anionic and a cationic centre in the same molecule, but are not considered salts. Examples of zwitterions are amino acids, many metabolites, peptid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element with the Symbol (chemistry), symbol Ag (from the Latin ', derived from the Proto-Indo-European wikt:Reconstruction:Proto-Indo-European/h₂erǵ-, ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc Refining (metallurgy), refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes bimetallism, alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable metallic form ( native metals). This led to very early human use in several regions, from circa 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, circa 5000 BC; the first metal to be cast into a shape in a mold, c. 4000 BC; and the first metal to be purposely alloyed with another metal, tin, to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper Nanoparticle
A copper nanoparticle is a copper based particle 1 to 100 nm in size.Khan, F.A. ''Biotechnology Fundamentals''; CRC Press; Boca Raton, 2011 Like many other forms of nanoparticles, a copper nanoparticle can be prepared by natural processes or through chemical synthesis. These nanoparticles are of particular interest due to their historical application as coloring agents and the biomedical as well as the antimicrobial ones. Historical uses One of the earliest uses of copper nanoparticles was to color glass and ceramics during the ninth century in Mesopotamia. This was done by creating a glaze with copper and silver salts and applying it to clay pottery. When the pottery was baked at high temperatures in reducing conditions, the metal ions migrated to the outer part of the glaze and were reduced to metals. The end result was a double layer of metal nanoparticles with a small amount of glaze in between them. When the finished pottery was exposed to light, the light would penetra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Nanoparticle
Silver nanoparticles are nanoparticles of silver of between 1 nm and 100 nm in size. While frequently described as being 'silver' some are composed of a large percentage of silver oxide due to their large ratio of surface to bulk silver atoms. Numerous shapes of nanoparticles can be constructed depending on the application at hand. Commonly used silver nanoparticles are spherical, but diamond, octagonal, and thin sheets are also common. Their extremely large surface area permits the coordination of a vast number of ligands. The properties of silver nanoparticles applicable to human treatments are under investigation in laboratory and animal studies, assessing potential efficacy, biosafety, and biodistribution. Synthesis methods Wet chemistry The most common methods for nanoparticle synthesis fall under the category of wet chemistry, or the nucleation of particles within a solution. This nucleation occurs when a silver ion complex, usually AgNO3 or AgClO4, is reduced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glazing (window)
Glazing, which derives from the Middle English for 'glass', is a part of a wall or window, made of glass. Glazing also describes the work done by a professional "glazier". Glazing is also less commonly used to describe the insertion of ophthalmic lenses into an eyeglass frame. Common types of glazing that are used in architectural applications include clear and tinted float glass, tempered glass, and laminated glass as well as a variety of coated glasses, all of which can be glazed singly or as double, or even triple, glazing units. Ordinary clear glass has a slight green tinge but special colorless glasses are offered by several manufacturers. Glazing can be mounted on the surface of a window sash or door stile, usually made of wood, aluminium or PVC. The glass is fixed into a rabbet (rebate) in the frame in a number of ways including triangular glazing points, putty, etc. Toughened and laminated glass can be glazed by bolting panes directly to a metal framework by bolts pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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