|
BARS Apparatus
BARS (or "split sphere", transliteration from abbreviation of , (bespressovaya apparatura vysokogo davleniya «razreznaya sfera»), "press-free high-pressure setup «split sphere»") a high-pressure high-temperature apparatus usually used for growing or processing minerals, especially diamond and boron nitride. Typical pressures and temperatures achievable with BARS are and . The BARS technology was invented around 1989–1991 by the scientists from the Institute of Geology and Geophysics of the Siberian Branch of the Russian Academy of Sciences, Siberian Branch of the Academy of Sciences of the USSR. In the center of the device, there is a ceramic cylindrical reaction cell of about 2 cm3 in size. The cell is placed into a cubic-shaped pressure-transmitting material, which is pressed by elements made from cemented carbide (VK10 hard alloy). The outer octahedral cavity is pressed by 8 steel sectors. After mounting, the whole assembly is locked in a disc-type barrel with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermocouple
A thermocouple, also known as a "thermoelectrical thermometer", is an electrical device consisting of two dissimilar electrical conductors forming an electrical junction. A thermocouple produces a temperature-dependent voltage as a result of the Seebeck effect, and this voltage can be interpreted to measure temperature. Thermocouples are widely used as list of temperature sensors, temperature sensors. Commercial thermocouples are inexpensive, interchangeable, are supplied with standard Electrical connector, connectors, and can measure a wide range of temperatures. In contrast to most other methods of temperature measurement, thermocouples are self-powered and require no external form of excitation. The main limitation with thermocouples is accuracy; system errors of less than one degree Celsius (°C) can be difficult to achieve. Thermocouples are widely used in science and industry. Applications include temperature measurement for kilns, gas turbine exhaust, diesel engines, and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Inventions
This timeline of Russian innovation encompasses key events in the history of technology in Russia. The entries in this timeline fall into the following categories: * indigenous invention, like airliners, AC transformers, radio receivers, television, artificial satellites, ICBMs * uniquely Russian products, objects and events, like Saint Basil's Cathedral, Matryoshka dolls, Russian vodka * products and objects with superlative characteristics, like the Tsar Bomba, the AK-47, and the Typhoon-class submarine * scientific and medical discoveries, like the periodic law, vitamins and stem cells This timeline includes scientific and medical discoveries, products and technologies introduced by various peoples of Russia and its predecessor states, regardless of ethnicity, and also lists inventions by naturalized immigrant citizens. Certain innovations achieved internationally may also appear in this timeline in cases where the Russian side played a major role in such projects. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Processes
Industrial processes are procedures involving chemical, physical, electrical, or mechanical steps to aid in the manufacturing of an item or items, usually carried out on a very large scale. Industrial processes are the key components of heavy industry. Chemical processes by main basic material Certain chemical process yield important basic materials for society, e.g., (cement, steel, aluminum, and fertilizer). However, these chemical reactions contribute to climate change by emitting carbon dioxide, a greenhouse gas, through chemical reactions, as well as through the combustion of fossil fuels to generate the high temperatures needed to reach the activation energies of the chemical reactions. Cement (the paste within concrete) * Calcination – Limestone, which is largely composed of fossilized calcium carbonate (CaCO3), breaks down at high temperatures into useable calcium oxide (CaO) and carbon dioxide gas (), which gets released as a by-product. This chemical reaction, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamond
Diamond is a Allotropes of carbon, solid form of the element carbon with its atoms arranged in a crystal structure called diamond cubic. Diamond is tasteless, odourless, strong, brittle solid, colourless in pure form, a poor conductor of electricity, and insoluble in water. Another solid form of carbon known as graphite is the Chemical stability, chemically stable form of carbon at Standard temperature and pressure, room temperature and pressure, but diamond is metastable and converts to it at a negligible rate under those conditions. Diamond has the highest Scratch hardness, hardness and thermal conductivity of any natural material, properties that are used in major industrial applications such as cutting and polishing tools. Because the arrangement of atoms in diamond is extremely rigid, few types of impurity can contaminate it (two exceptions are boron and nitrogen). Small numbers of lattice defect, defects or impurities (about one per million of lattice atoms) can color ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamond Enhancement
Diamond enhancements are specific treatments, performed on natural diamonds (usually those already cut and polished into gems), which are designed to improve the visual gemological characteristics of the diamond in one or more ways. These include clarity treatments such as laser drilling to remove black carbon inclusions, fracture filling to make small internal cracks less visible, color irradiation and annealing treatments to make yellow and brown diamonds a vibrant fancy color such as vivid yellow, blue, or pink. The CIBJO and government agencies, such as the United States Federal Trade Commission, explicitly require the disclosure of all diamond treatments at the time of sale. Some treatments, particularly those applied to clarity, remain highly controversial within the industry—this arises from the traditional notion that diamonds hold a unique or "sacred" place among the gemstones, and should not be treated too radically, if for no other reason than a fear of damaging con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diamond Color
A chemically pure and structurally perfect diamond (gemstone), diamond is perfectly transparent with no hue, or color. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The color of a diamond may be affected by colors of chemicals, chemical impurities and/or structural defects in the Crystal structure#Lattice systems, crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's color can either detract from or enhance its value. For example, most colorless (white) diamonds are discounted in price when more yellow hue is detectable, while intense pink diamonds or blue diamonds (such as the Hope Diamond) can be dramatically more valuable. Of all colored diamonds, red diamonds are the rarest. The Aurora Pyramid of Hope displays a spectacular array of naturally colored diamonds, including red diamonds. History of color grading Color grading of diamonds was performed as a step of sorting rough diamonds for sale by the Londo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Material Properties Of Diamond
Diamond is the allotrope of carbon in which the carbon atoms are arranged in the specific type of cubic lattice called diamond cubic. It is a crystal that is transparent to opaque and which is generally isotropic (no or very weak birefringence). Diamond is the hardest naturally occurring material known. Yet, due to important structural brittleness, bulk diamond's toughness is only fair to good. The precise tensile strength of bulk diamond is little known; however, compressive strength up to has been observed, and it could be as high as in the form of micro/nanometer-sized wires or needles (~ in diameter, micrometers long), with a corresponding maximum tensile elastic strain in excess of 9%. The anisotropy of diamond hardness is carefully considered during diamond cutting. Diamond has a high refractive index (2.417) and moderate dispersion (0.044) properties that give cut diamonds their brilliance. Scientists classify diamonds into four main types according to the nature of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synthetic Diamond
A synthetic diamond or laboratory-grown diamond (LGD), also called a lab-grown, laboratory-created, man-made, artisan-created, artificial, or cultured diamond, is a diamond that is produced in a controlled technological process, in contrast to a naturally-formed diamond, which is created through geological processes and obtained by mining. Unlike diamond simulants (imitations of diamond made of superficially similar non-diamond materials), synthetic diamonds are composed of the same material as naturally formed diamonds—pure carbon crystallized in an isotropic 3D form—and have identical chemical and physical properties. The maximal size of synthetic diamonds has increased dramatically in the 21st century. Before 2010, most synthetic diamonds were smaller than half a carat. Improvements in technology, plus the availability of larger diamond substrates, have led to synthetic diamonds up to 125 carats in 2025.=https://www.gia.edu/gia-news-research/gems-gemology-summary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the increase in rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. The rate increase occurs because the catalyst allows the reaction to occur by an alternative mechanism which may be much faster than the noncatalyzed mechanism. However the noncatalyzed mechanism does remain possible, so that the total rate (catalyzed plus noncatalyzed) can only increase in the presence of the catalyst and never decrease. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usual ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystallographic Defects In Diamond
Imperfections in the crystal lattice of diamond are common. Such defects may be the result of lattice irregularities or extrinsic substitutional or interstitial impurities, introduced during or after the diamond growth. The defects affect the material properties of diamond and determine to which type a diamond is assigned; the most dramatic effects are on the diamond color and electrical conductivity, as explained by the electronic band structure. The defects can be detected by different types of spectroscopy, including electron paramagnetic resonance (EPR), luminescence induced by light (photoluminescence, PL) or electron beam (cathodoluminescence, CL), and absorption of light in the infrared (IR), visible and UV parts of the spectrum. The absorption spectrum is used not only to identify the defects, but also to estimate their concentration; it can also distinguish natural from synthetic or enhanced diamonds. Labeling of diamond centers There is a tradition in diamond spectr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electricity
Electricity is the set of physical phenomena associated with the presence and motion of matter possessing an electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by Maxwell's equations. Common phenomena are related to electricity, including lightning, static electricity, electric heating, electric discharges and many others. The presence of either a positive or negative electric charge produces an electric field. The motion of electric charges is an electric current and produces a magnetic field. In most applications, Coulomb's law determines the force acting on an electric charge. Electric potential is the Work (physics), work done to move an electric charge from one point to another within an electric field, typically measured in volts. Electricity plays a central role in many modern technologies, serving in electric power where electric current is used to energise equipment, and in electronics dealing w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
