bluuebunny/crossref_metadata_2025_split huggingface dataset:
Helium Group Compounds
Authors: Schrobilgen Gary J. , Whalen J. Marc 
Published: August 2004

AbstractCompounds of the helium‐group gases, known since 1962, are limited to those of xenon, krypton, and radon. These heavy noble gases form stable compounds and adducts with fluorine and other powerful oxidants. Xenon has the best studied, most extensive chemistry. The oxidation states observed for xenon range from\documentclass{article}\pagestyle{empty}\begin{document}${+}$\end{document}to\documentclass{article}\pagestyle{empty}\begin{document}${+8}$\end{document}. Bonds to fluorine, oxygen, nitrogen, and carbon have been characterized. The chemistry of krypton, which has one known oxidation state,\documentclass{article}\pagestyle{empty}\begin{document}${+2}$\end{document}, is far less extensive, but bonds to fluorine, oxygen, and nitrogen have been characterized. That of radon is even less well characterized and is limited to fluoride species of the\documentclass{article}\pagestyle{empty}\begin{document}${+2}$\end{document}oxidation state. Properties of the compounds are reviewed.
Copper
Authors: George David B. 
Published: August 2004

Abstract
Copper and its various alloys are used in industrial and consumer applications because of high electrical and thermal conductivities, wear and corrosion resistance, and mechanical and aesthetic properties. These metals are vital to nearly every industrial sector. Uses of copper and alloy mill products may be broken down into five principal markets: building construction, electrical and electronic products, industrial machinery and equipment, transportation, and consumer and general products. In addition, copper and its alloys are a strategic material essential to the production of equipment critical to the U.S. economy and national defense.
The various copper minerals, mining, ore treatment, smelting, and refining are discussed as is fabrication of products and the chemical reactions specific to these processes. There have been significant process innovations in the copper industry, particularly in hydrometallurgy, solvent‐extraction technology, and continuous casting production methods.
Pure copper is most often produced by electromining. Sulfuric acid is a principal by‐product of copper refining. The United States is a world leader in smelting and refining capacity. It is the second largest copper ore producer and repository of one‐fifth of the world's recoverable reserves. U.S. and world production is discussed.
Copper Compounds
Authors: Wayne Richardson H. 
Published: August 2004

AbstractAn overview of copper compounds is presented with the emphasis on those compounds of key industrial importance. The chemistry and stability of copper in its various oxidation states and with regard to coordination complexes are discussed. The primary methods of manufacture for many commercially significant compounds are given as are the most usual methods of analysis. The uses of copper in agriculture, as a nutritional fungicide and algicide are discussed. The various copper‐bond fungicides are listed. Other uses of copper compounds such as in catalysis, electronics, and electroplating are mentioned. Copper compounds are also used as pigments, in wood preservation and electroless plating, and in solar collectors.
Cyanamides
Authors: Patel Baldev K. 
Published: August 2004

AbstractCyanamide has been commercially available, as calcium salt, since the beginning of the twentieth century. A commercial process for manufacturing a pure grade of cyanamide was introduced in 1964. Cyanamide was widely used as a nitrogen fertilizer and later as a raw material for dicyandiamide and melamine.The use of cyanamide as a fertilizer has been replaced by ammonia and urea. Melamine is now made by a petrochemical process using natural gas. Cyanamide is still used in the manufacture of dicyandiamide and calcium cyanide. Cyanamide‐based chemicals have also been used in special applications for defoliants, fungicides, herbicides, and as a weed killer. In pure form, cyanamides are used in the synthesis of many complex chemicals.Calcium cyanamide is produced by both batch oven and continuous kiln processes. This article deals with the chemistry, manufacture, specifications, health and safety factors (toxicity and environment), and use of cyanamide homologues: cyanamide, dicyandiamide, and melamine.
Cyanuric and Isocyanuric Acids
Authors: Wojtowicz J. A. 
Published: August 2004

AbstractCyanuric acid has been known for over 200 years, but achieved commercial importance only in the mid‐1950s primarily via its derivatives. The chemistry of cyanuric acid is diversified because of multiple reaction sites.N‐Chlorination of cyanuric acid produces chloroisocyanurates that are widely used as disinfectants, sanitizers, and bleaches. The triallyl‐ and tris(2‐hydroxyethyl) derivatives are employed as cross‐linking and curing agents, and tris(2,3‐epoxypropyl)isocyanurate is used in weather‐resistant powder coatings. Melamine cyanurate finds significant use as a fire retardant in plastics. Considerable interest has developed in the use of cyanuric acid for reduction of nitrogen oxides in exhaust gases from combustion of oil, gas, and coal.Nomenclature is based on the keto‐enol tautomers. The trihydroxy form is variously designated cyanuric acid,s‐triazine‐2,4,6‐triol or 2,4,6‐trihydroxy‐s‐triazine. The trioxo structure, ors‐triazine‐2,4,6(1H,3H,5H)‐trione is the basis for the isocyanuric acid nomenclature. The triazine‐based system is preferred in the scientific literature and is used by government regulatory agencies; however, the less cumbersome (iso)cyanurate designations persist in commerce. The keto form normally predominates in cases of keto‐enol tautomerism. In alkaline solution, the anion formed is that of the hydroxy tautomer. Through common usage, both forms are collectively called cyanuric acid (CA).
Defoamers
Authors: Owen Michael J. 
Published: August 2004

AbstractModern defoamers are complex formulated products of vital importance in a wide variety of industries. A classification by chemical type is presented based on active liquid and solid phase components and ancillary surface‐active materials and carriers. Traditional vegetable and mineral oils, poly(oxypropylene), polydimethylsiloxane, alkyl phosphates, acetylenic glycols, hydrophobic silica, and solid fatty amides are included together with examples of commercial sources. Current theory of defoaming is reviewed from the perspective of the spreading properties of liquid‐phase components and the dewetting of foam films from the solid‐phase components. Emphasis is on surface dilatational properties, using silicone defoaming of crude oils as an example, and on the role of the dispersed hydrophobic solids in aqueous defoaming, using hydrophobic silica as the example. The principal industries and application areas where defoamer use is most critical are reviewed including adhesives and sealants, chemical processing, cleaning compounds, construction, fermentation, fertilizers, food and beverages, leather, metal working, oil and petroleum, paints and coatings, polymers, pulp and paper, textiles, and wastewater treatment. Economic aspects, test methods, and health and safety factors are also briefly covered.
Dental Materials
Authors: Tesk John A. , Antonucci Joseph M. , Eichmiller Fred C. , Kelly J. Robert , Rupp Nelson W. , Waterstrat Richard W. , Fraker Anna C. , Chow Lawrence C. , George Laurie A. , Stansbury Jeffrey W. , Parry Edward E. 
Published: August 2004

AbstractDental materials are those materials used to provide therapy for the hard and soft oral tissues. This therapy includes the replacement of oral tissues lost through disease with inert materials, ie, metallic, ceramic, and organic, or with composites employing combinations of these three broad classes. The operative restorations and prostheses are made of amalgam, precious and nonprecious alloys, special cements, synthetic polymers, porcelain, and glass‐ceramics, all of which must withstand the rigors of the oral environment (see also Prosthetic and Biomedical Devices). The accessory materials needed in the fabrication procedures include synthetic polymers, synthetic and natural gums and waxes, hydrocolloids, gypsums, and refractories.These materials are used by ca 170,000 practicing dentists in the United States (1992) and more than 8,500 commercial U.S. dental laboratories employing ca 40,000–50,000 technicians.
Deuterium and Tritium, Deuterium
Authors: Katz Joseph J. 
Published: August 2004

AbstractDeuterium (2H or D) the heavier, stable isotope of hydrogen (1H) occurs in nature, and is always present in all hydrogen‐containing compounds. Deuterium oxide, known as heavy water, is the most important deuterium compound. Heavy water differs from ordinary water in structure of the liquid phase, in nuclear spin, ionic equilibria, and in various spectroscopic properties. Kinetic isotope effects occur in chemical reactions involving bond rupture of H and D. This effect in hydrogen exchange between water and hydrogen sulfide is the basis for the most important separation process for large‐scale deuterium production. Infrared absorption is the method of choice for the analysis of heavy water. Deuterium has far‐reaching biological effects, and it is possible to grow living organisms in which all of the hydrogen normally present is replaced by deuterium. The nuclear properties of deuterium are such that heavy water is the most efficient neutron moderator known for nuclear fission reactors. Deuterium is also important in nuclear fusion technology.
Dispersants
Authors: Hann William M. 
Published: August 2004

AbstractDispersants are polymeric compounds that help maintain fine solid particles in suspension in a fluid medium or that inhibit the growth of crystallites in a supersaturated solution. Dispersants function by adsorbing on active sites in a growing crystal or by adsorbing on solid particle surfaces to provide a barrier that prevents particle aggregation. This barrier can be due to coulombic (charge) repulsion, steric repulsion, or both. Significant uses for dispersants include detergent builder assists, water treatment applications, paint and pigment dispersing, and in cements to increase workability. The principal types of dispersants are polyphosphates, polyacrylates, polymaleates, melamine‐ or naphthalene‐sulfonic acid condensates, and natural product‐derived dispersants. In general, dispersants are used to prevent settling, deposition, precipitation, agglomeration, flocculation, coagulation, adherence, or caking of solid particles.
Drug Delivery Systems
Authors: Quadros Elizabeth , Comfort Ann R. , Dinh Steven M. , Berner Bret 
Published: August 2004

AbstractThe concepts of drug delivery are described, focusing on the application of polymer chemistry to design a well‐characterized controlled dosage form that produces the desired drug delivery profile. In order to design a system, both drug release from the system, ie, desorption or dissolution, and absorption across the relevant biological membrane are measured. The physiology and barrier properties of different routes of drug delivery, which include oral, rectal, transdermal, buccal, nasal, pulmonary, ocular, and vaginal, are described. The mechanisms that govern drug release from systems include diffusion (including osmotic), chemical, swelling, and external control, such as iontophoresis or electromechanical devices. Examples are given of commercially available systems from each class, including implants, oral osmotic devices, transdermal and ocular systems, and infusion pumps. Characterization of the physical and chemical properties of the system components is described, as well as the different types of manufacturing processes and characterization of the final system, including drug release and adhesion, if relevant.
Dyes, Environmental Chemistry
Authors: Reife Abraham 
Published: August 2004

AbstractSynthetic organic dyes are essential to satisfy the ever growing demands in terms of quality, variety, fastness, and other technical requirements for coloration of a growing number of substances. Beginning in 1970, however, the dyestuff and textile industries have become increasingly subject to international, federal, and state regulations designed to improve health, safety, and environment. Therefore, in an attempt to provide a perspective of the environmental problems posed by synthetic organic colorants, and the efforts being made by industry, academia, and government to solve these problems, this article includes the physical, chemical, and biological methods of effluent treatment of dye wastewater. Specifically, the physical methods are adsorption, sedimentation, flotation, flocculation, coagulation, foam fractionation, polymer flocculation, reverse osmosis and ultrafiltration, ionization radiation, and incineration; the chemical methods are neutralization, reduction, oxidation, electrolysis, ion exchange, and wet air oxidation; the biological methods are stabilization ponds, aerated lagoons, trickling filters, activated sludge, anaerobic digestion, and bioaugmentation. Also included are fate of dyes, analytical methods, pollution prevention, heavy metals, toxicity, and legislation.
Dyes, Reactive
Authors: Smith Roy E. 
Published: August 2004

AbstractReactive dyes are those dyes that are electrophilic and react with a nucleophilic group of a substrate to form a covalent chemical bond. They offer improved washfastness over dyes that are mechanically entrapped by the substrate. Brighter shades can be obtained on cellulose with reactive dyes than with large molecular weight direct dyes.Reactive dyes for cellulose were first commercialized by ICI in 1956 under the trade name Procion M. The reactive group of those dyes was dichlorotriazine. Since that time more than 40 reactive groups have been reported. However, the most important groups for cellulose are monochlorotriazine, vinyl sulfone, and monofluorotriazine, in order of increasing reactivity. Acrylamide andα‐bromoacrylamide are the most important reactive groups for wool where usage is minimal compared to cellulose. Difunctional reactive dyes with functional groups of different reactivity were commercialized in the early 1980s, and gave much greater substantivity on cellulose than had previously been possible.Since about 1980 reactive dyes have represented the principal research and development efforts among the several classes of textile dyes. Most efforts are directed toward improved dye fixation on the substrate to minimize ecological adversities and improve economics. The most common approach to achieve this objective is the use of bifunctional dyes, which may be applied over a wide range of reaction conditions. Reactivity may be varied by selection of reactive group, or by inductive effects of the dye chromophore on the reactive group.
Dyes, Sensitizing
Authors: Sturmer David M. 
Published: August 2004

AbstractSpectral sensitizing dyes enhance the colors and wavelengths to which photosensitive systems respond. Color photography requires spectral sensitizers for each of the color regions of the visible spectrum (blue, green, and red). Infrared spectral sensitizers are essential to a wide variety of processes, including infrared photography, electrophotography, and optical disk data storage. Chlorophyll is the natural sensitizer in plants, and retinal derivatives activate our vision system. Other spectral sensitizers find specialty uses in photoresists, solid‐state laser‐activated printing, graphic arts/x‐ray films, manufacture of perfume constituents, and photochemical disease therapy.
Economic Evaluation
Authors: Ward Thomas J. 
Published: August 2004

Abstract
Economic evaluation is the financial assessment of a proposed venture, relative to other possible choices. Problem definition is the first part of economic evaluation. Cost estimation involves equipment, capital investment, and product cost. Revenue estimation considers product price and factor estimates. Profitability analysis utilizes multiyear process ventures, ie, money flows of capital investments, sales revenues, annual cash flow, etc; and profitability criteria, ie, net present value, discounted total capital, internal return rate, etc. Cash flow examples are included, as are profitability and sensitivity diagrams. Break‐even charts, inflationary effects, and statistical analysis are also discussed.
Electroplating
Authors: Horner Jack 
Published: August 2004

AbstractElectroplating is a diversified industry using a variety of metals and alloys to plate on many base materials for a wide range of both decorative and functional applications. Whereas the majority of substrates are metals and alloys, there are a large and growing number of plastics being plated. More electroplated materials are used for their functional properties than for their decorative ones.The fundamentals of the electroplating process, cleaning and preparation of the base materials, bath formulations, operating conditions, and the properties of the electroplated deposits are presented. The overall environmental impact of the industry is discussed with an eye to waste management. Changes in the electroplating industry, such as the increased use of trivalent chromium and zinc alloys, are being environmentally driven.
Electrically Conductive Polymers
Authors: Reynolds John R. , Child Andrew D. , Gieselman Melinda B. 
Published: August 2004

AbstractAn overview of the field of electrically conductive polymers is presented. The synthesis of conducting polymers is discussed with detailed sections describing polyacetylenes, polyphenylenes, polyheterocycles, poly(arylene vinylenes), and polyanilines. The preparations of conducting polymer blends, composites, and colloids are described. The concept of redox doping to form charge carriers on conjugated polymers and its effect on optical and electrical properties is given. The effect of polymer structure on electronic properties is demonstrated. The stabilities of conducting polymers are compared. A number of applications are outlined; these include charge storage batteries, conductive textiles, chemical biochemical sensors, electromagnetic shielding, antistatic coatings, gas separation membranes, electrochromism, and electroluminescence.
Emulsions
Authors: Friberg Stig E. , Jones Steven 
Published: August 2004

Abstract
The formation, stability, and applications of emulsions are reviewed with the focus on more complex systems than the traditional two‐phase liquid‐in‐liquid dispersions. The presence of a third phase is demonstrated to change the properties of the emulsion in a significant manner and is, in fact, in some cases a necessity for specific applications.
Enzyme Inhibitors
Authors: Muscate Angelika , Levinson Cynthia L. , Kenyon George L. 
Published: August 2004

AbstractModern approaches to rational drug discovery have led to a number of different strategies for the design of enzyme active‐site directed inhibitors, which can be divided into classes describing noncovalent and covalent binding. Noncovalently binding inhibitors can be subdivided into rapidly reversible, tight, slow, slow‐tight binding inhibitors, transition‐state, and multisubstrate analogues. Covalently binding inhibitors are grouped into mechanism‐based inhibitors, affinity labels, and pseudoirreversible inhibitors. Inhibitors that fall into one or more of these categories have been designed using mechanistic and structural information. Computer‐aided drug design has been used as a new and powerful approach for the design of inhibitors. Using three‐dimensional enzyme structures or pharmacophores, novel, nonsubstrate analogue lead compounds have been developed byde novodesign or screening of small molecule databases and further optimized to obtain potent inhibitors. Alternatively, quantitative structure‐activity relationship methods (QSAR), comparative molecular field analysis (CoMFA), or perturbation free‐energy calculations have used the speed and computational power of computer algorithms to establish structure‐activity relationships for a series of structurally related compounds, allowing for the design of more potent inhibitors.
Ethanol
Authors: Logsdon John E. 
Published: August 2004

AbstractEthanol's unique combination of physical and chemical properties has led to its use as a solvent, a germicide, a beverage, an antifreeze, a fuel, a depressant, and a chemical intermediate for other organic chemicals. Most industrial ethanol is produced from ethylene by the direct hydration process. Ethanol from fermentation processes is the second most important source. The subsidized (federal and state) use of fermentation ethanol in gasoline has fueled a rapid growth in U.S. production, which has provided some ethanol for crossover to the industrial market. The 1990 Clean Air Act requiring the use of oxygenates in gasoline has further fueled this growth. Corn is the principal feedstock for fermentation in the United States, and sugar cane is the most important raw material outside the United States. This rapid growth has also caused a renewed interest in research into this ancient process. The main uses for industrial ethanol are as an intermediate for the production of other chemicals and as a solvent. The United States Treasury, Bureau of Alcohol, Tobacco, and Firearms oversees the production, procurement, and use of ethanol in the United States.
Ethyl Chloride
Authors: Miller Matt C. 
Published: August 2004

AbstractEthyl chloride (chloroethane), C2H5Cl, is a colorless, mobile liquid with a nonirritating ethereal odor and a pleasant taste. It is flammable, is normally stored as liquefied gas, and burns with a green‐edged flame, producing hydrogen chloride fumes. This article discusses its properties, manufacture, toxicology, and economic aspects. Ethyl chloride has primarily been used in the manufacture of the fuel additive tetraethyllead (TEL). Environmental legislation mandating the use of lead‐free fuels has caused a steep decline in production of ethyl chloride. A recent study has shown evidence of carcinogenic activity in female mice exposed to 15,000 ppm. The only other important demand for ethyl chloride is in the production of ethylcellulose.
Ethylene–Propylene–Diene Rubber
Authors: Noordermeer Jacobus W. M. 
Published: August 2004

AbstractEPM and EPDM are the fastest growing elastomers by virtue of their excellent ozone resistnce in comparison with commodity rubbers. Even though these rubbers have been commercially available for more than 30 years, the production and applications technologies are still very much under development. The various structural parameters of EP(D)M are described, as well as how these depend on production conditions. EP(D)M is produced in suspension with liquid propylene as dispersing agent, or most commonly in solution where the polymer produced is dissolved in a hydrocarbon solvent. The solution process technology is described in detail. EP(D)M can be compounded with fillers and plasticizers. Basic principles of compounding are described, including a few typical examples of EP(D)M recipes. EP(D)M can be mixed, extruded, and vulcanized on all common rubber‐factory equipment.The mechanical properties depend considerably on the structural characteristics of the EP(D)M and the type and amount of fillers in the compound. Some typical properties of EP(D)M vulcanizates are good elastic properties, resistance to heat and ozone, various chemicals, and good electrical properties. The principal uses of vulcanized EP(D)M rubber are in automotive, building and construction, cable and wire, and appliances. Unvulcanized EP(D)M rubber is mainly used in blends with thermoplastics, particularly polypropylene, and as an oil additive.