bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyanine Dyes
Authors: Sturmer David M. 
Published: August 2004

AbstractCyanine dyes and the related merocyanines and oxonols are commercially important dyes for high technology uses, including spectral sensitization of photographic films, optical filtering/light modulation, dye lasers, and biological staining agents. The primary chromophores and heterocycles in these dyes are outlined with specific reference to chemical reactions that allow the synthesis of almost every type of cyanine and related dye. Known structure‐property relationships for the cyanines are extensive, and examples are included for properties such as color, substituent effects, solubility, self‐association (aggregation), electrochemical behavior, photochemical reactions, and biological uses.
Cyclopentadiene and Dicyclopentadiene
Authors: Keenan Michael J. 
Published: August 2004

AbstractCyclopentadiene is the most widely studied, conjugated cyclodiene in the history of organic chemistry. The more stable form, dicyclopentadiene, has a multitude of applications. This article discusses the physical properties of these compounds, chemical reactions, derivatives, manufacturing processes, and applications.Cyclopentadiene undergoes the Diels‐Alder reaction with itself and with a wide variety of olefins and diolefins. In addition, it can be functionalized to many derivatives and can be polymerized with itself and other olefins. The derivatives are used in polyesters, perfumes, elastomers, and pesticides. Metallocene complexes of cyclopentadiene have been extensively studied and are useful as catalysts.Dicyclopentadiene is used in polymers with itself and with other hydrocarbons, in polyester resins, bodied oils, elastomers, polycarbonates, and pharmaceuticals. Total worldwide recoverable dicyclopentadiene capacity exceeds 175,000 metric tons per year.
Design of Experiments
Authors: Hahn Gerald J. 
Published: August 2004

AbstractThe main reason for designing an experiment statistically is to obtain unambiguous results at a minimum cost. The need to learn about interactions among variables and to measure experimental error are added reasons.Statistically planned experiments are characterized by (1) the proper consideration of extraneous variables; (2) the fact that primary variables are changed together, rather than one at a time, in order to obtain information about the magnitude and nature of interactions and to gain improved precision in the final estimates; and (3) built‐in procedures for measuring the various sources of random variation and for obtaining a valid measure of experimental error.A well‐planned experiment is often tailor‐made to meet specific objectives and to satisfy practical constraints. The final plan may or may not involve a standard textbook design. If possible, a statistician knowledgeable in the design of experiments should be called in early, made a full‐fledged team member, and be fully apprised of the objectives of the test program and of the practical considerations and constraints. Designing an experiment is often an iterative process requiring rework as new information and preliminary data become available. With a full understanding of the problem, the statistician is in an improved position to respond rapidly if last‐minute changes are required and to provide meaningful analyses of the subsequent experimental results.
Diamines and Higher Amines, Aliphatic
Authors: Carter Richard G. , Doumaux Arthur R. , Kaiser Steven W. , Umberger Pamla R. 
Published: August 2004

AbstractThe aliphatic diamine and higher amine family encompasses a wide range of multifunctional and multireactive compounds. The so‐called ethyleneamines family, which includes ethylenediamine and its homologues, the polyethylene polyamines, have found the broadest commercial application. Representative physical and chemical properties are given. Three main processes are used currently to produce the ethyleneamines: the reaction of ethylene dichloride with ammonia to produce the whole spectrum of ethyleneamine products; the reductive amination of monoethanolamine to produce the lighter ethyleneamines, mainly ethylenediamine; and the catalytic reaction of monoethanolamine with ethylenediamine to produce higher ethyleneamines. Worldwide capacity for ethyleneamines is about 295 t/yr. Typical specifications and test methods, storage and handling guidelines, and health and safety factors are discussed. This family of compounds finds use in a wide variety of applications by virtue of their unique combination of reactivity, basicity, and surface activity. With a few significant exceptions, they are used predominantly as intermediates in the production of functional products. Significant applications include fungicides, lubricant and fuel additives, epoxy curing agents, polyamide resins, paper resins, and chelates.
Chlorine Oxygen Acids and Salts, Dichlorine Monoxide, Hypochlorous Acid, and Hypochlorites
Authors: Wojtowicz John A. 
Published: August 2004

AbstractThe hydrolysis of chlorine gives rise to a pH‐dependent complex system involving no less than six equilibria in which the oxidizing power of the parent element is preserved in hypochlorous acid, chlorine monoxide, and hypochlorite. The physical and chemical aspects of this unique family of compounds, including organic and other nonmetal hypochlorites, are outlined, their preparation and manufacturing processes are surveyed, and important uses are cited. Corrosion problems and potential hazards in handling and use of these compounds are also discussed.Hypochlorous acid is the active biocidal agent when hypochlorites are employed in disinfection and sanitation. It is an intermediate in the manufacture of hypochlorites, chloramines, and chlorohydrins. A process for production of HOCl in concentrations as high as 60% has recently been developed.The commercially important hypochlorites are Ca(OCl)2, NaOCl solution, LiOCl, chlorinated trisodium phosphate, and to a lesser extent hemibasic Ca(OCl)2and bleaching powder. They are used primarily in sanitation and bleaching applications. Although the use of chloroisocyanurates in swimming pool sanitation is increasing, hypochlorites remain the dominant products in this area. The most important solid hypochlorite is Ca(OCl)2, which is marketed in partially hydrated form and to a lesser extent as an almost anhydrous product. Several new processes for its manufacture are described.Continued research interest involve use of hypochlorites for selective epoxidation, oxidation, and chlorination, and use of chlorine monoxide as a highly selective agent for aromatic ring and side chain chlorination.
Disinfectants and Antiseptics
Authors: Block Seymour S. 
Published: August 2004

AbstractDisinfectants and antiseptics are employed in the prevention of diseases of bacterial, parasitic, fungal, and viral origin. Hospital acquired infections, AIDS, Legionnaires disease, tuberculosis, and cholera are a few of the diseases controlled in part through the use of disinfectants and antiseptics.Disinfectants and antiseptics are antimicrobial agents used as preservatives, sporicides, sanitizers, etc. Chemical groups employed as disinfectants and antiseptics include halogens, acids, aldehydes, nitrogen heterocycles, peroxygen, phenolic, and sulfur metal compounds. Disinfectants also may be classified as either surface‐active agents or gaseous sterilants. Numerous analytical tests exist for establishing the activity and application of disinfectants. Antiseptics, considered drugs, come under the jurisdiction of FDA testing guidelines.
Distillation
Authors: Fair James R. 
Published: August 2004

AbstractDistillation is the most widely used industrial method for separating liquid mixtures into their constituents. In chemical plants and petroleum refineries, distillations are normally carried out in vertical columns containing devices for bringing the flowing liquid mixture into intimate contact with a flowing vapor mixture that is generated by partial vaporization of the liquid. This article covers the fundamental physical and mathematical relationships that are needed for the design of new distillation columns as well as the analysis of existing columns.The article is divided into four main topics: vapor‐liquid equilibria; distillation processes; distillation columns, both plate and packed; and distillation as a separation method. Minor divisions include such special topics as steam distillation, molecular distillation, distillation literature sources, and economics. Sufficient information is given to enable the user to carry out preliminary designs of a variety of systems, and guidance is provided for cases where additional resources might be needed.
Drying
Authors: McCormick Paul Y. 
Published: August 2004

AbstractDrying is an operation in which volatile liquids are separated from solids, slurries, and solutions to yield solid products. Drying mechanisms and processes, including psychometry, heat‐ and mass‐transfer principles, and a description of liquid and vapor flow encountered during drying are discussed. In freeze drying (lyophilization), wet material is cooled to freeze the liquid and vaporization occurs by sublimation.Industrial dryers may be broadly classified according to the method of heat transfer as being either direct‐heat or indirect‐heat dryers. The types of dryers employed in the chemical industry, which may also be classified as batch or continuous, are described. Conventional, radiant, dielectric, and microwave heat sources are discussed as are emission control and energy usage of the various dryer types.
Drying Oils
Authors: Wicks Zeno W. 
Published: August 2004

Abstract
Natural and synthetic drying oils are discussed. Occurrence, isolation, composition, and analysis of oils is covered. Mechanism of drying through free‐radical initiated autoxidation is described with particular emphasis, in the case of oils with nonconjugated double bonds, of the role of activated methylene groups between double bonds. The reactions are catalyzed by oil‐soluble transition‐metal salts. Modified and synthetic oils include: varnishes, synthetically conjugated oils, esters of higher functionality polyols, maleic anhydride‐modified oils, and vinyl‐modified oils. Data on economic aspects and lists of specifications are included. Natural drying and semidrying oils as well as their fatty acids are used in making alkyds, epoxy esters, and urethane oils, which can properly be considered synthetic drying oils. Uses of drying oils discussed include paints, printing inks, and other uses.
Electroseparations, Electrophoresis
Authors: Rudge Scott , Markey Kathleen 
Published: August 2004

AbstractElectrophoresis is a separation technique which is most often applied to the analysis of biological and other polymeric samples. The principles, modes of operation, separation matrices, detection techniques, and equipment for the various electrophoresis techniques are presented. The three principal modes of electrophoresis, zone electrophoresis, isoelectric focusing, and isotachophoresis, are discussed, as are the advantages of the principal matrices in which electrophoresis is performed, including agarose, polyacrylamide, paper, capillaries, and flowing buffers. Specific examples of techniques such as immunochemical reaction, two‐dimensional techniques, and blotting are given.
Electroanalytical Techniques
Authors: Sandifer James R. 
Published: August 2004

AbstractElectroanalytical techniques may be classified as involving active or passive measurements. Active measurements, such as those obtained in coulometry and voltammetry, result from the application of a voltage or current. Passive measurements, such as those from an ion‐selective electrode, are made independently of external waveforms. The various electroanalytical techniques are described, as is the assembly of electrochemical cells for electroanalysis. Electroanalytical cells employ at least two electrodes placed in either aqueous or organic media. Analyte concentrations may be in the picomolar to molar range. Electroanalytical systems may be employed independently or in conjunction with a separation technique such as chromatography.
Embedding
Authors: Wong C. P. , Xu Jianwen 
Published: August 2004

AbstractAdvances in electronic technology have had great technological and economic impact on the electronic industry throughout the world. The rapid growth of the number of components per chip, the rapid decrease of device dimension, and the steady increase in IC chip size have imposed stringent requirements not only on IC physical design and fabrication, but also in electronic packaging and embedding. Electronic embedding is one of the most common processes used to encapsulate and protect electronic components. With advances in VLSI technology and multichip modules packaging, embedding of high density packages in electronics has become a challenge. Various polymeric encapsulants are used for embedding these types of electronic components. These materials, such as silicones, silicon‐carbon thermosets, epoxies, polyurethanes, polyesters, polysulfides, and advanced thermoplastics, and their electrical, mechanical, and rheological properties as well as material processes related to molding, potting, casting, and saturation coating processes, are discussed in detail. Furthermore the studies of material curing by differential calorimetry, ftir, and microdielectrometry are described.The development of a novel aluminum‐filled high dielectric composite is detached. Aluminum is a fast self‐passivation and low‐cost metal. The thin passivation layer forms a boundary layer outside of metallic spheres that has dramatic effects on the electrical, mechanical, and chemical behaviors of the resulting composites.
Ethylene Oxide
Authors: Dever J. P. , George K. F. , Hoffman W. C. , Soo H. 
Published: August 2004

AbstractEthylene oxide is a colorless gas that condenses at low temperatures into a liquid and is miscible with water and most organic solvents. Its vapors are flammable and explosive. Ethylene oxide can be relatively toxic as both a liquid or gas, and is considered as a potential human carcinogen and reproductive hazard.Ethylene oxide was first prepared from ethylene chlorohydrin and aqueous potassium hydroxide in 1859. It was first produced commercially during World War I in Germany by the chlorohydrin process. In 1931, direct oxidation of ethylene to ethylene oxide was achieved by using a silver catalyst. The chlorohydrin process was quickly replaced by the direct oxidation process, and is still the dominate technology.Ethylene oxide is a highly reactive compound; it is used industrially as an intermediate for many chemical products. The total world production capacity in 1992 was about 9.6 × 106metric tons. More than 98% of the total ethylene oxide production is converted to derivatives. About 60–65% is consumed in the manufacture of ethylene glycol. Other derivatives include glycol ethers, ethanolamines, and surfactants. The fastest growing market is expected to be ethylene glycol for polyester production.
Ethylene–Acrylic Elastomers
Authors: Dobel Theresa M. 
Published: August 2004

Abstract
Ethylene‐acrylate elastomers are a family of addition copolymers of ethylene and methyl acrylate that were commercialized under the trademark VAMAC by Du Pont Co. in 1975. Traditional grades of ethylene‐acrylic elastomers also have small amounts of a carboxylic monomer polymerized into the polymer backbone to provide cure sites for cross‐linking with amines. A line of copolymers of only ethlyene and methyl acrylate has been added to the ethylene‐acrylic family. In this article cure properties, aging characteristics, mechanical properties, and low temperature properties of ethylene‐acrylic elastomers are reviewed. Special compounded attributes such as uniquely temperature‐stable vibrational damping properties and the ability to produce flame‐resistant and smoke suppressive compounds are also discussed. Ethylene‐acrylic elastomers are processed in the same manner as other elastomers. Because of this balance of properties, ethylene‐acrylic elastomers have found ready acceptance in many high performance applications, especially in the automotive market.
Fermentation
Authors: Sengha Surjit S. 
Published: August 2004

Abstract
Fermentation uses microorganisms to manufacture products such as alcoholic beverages, antibiotics, enzymes, organic acids, amino acids, vitamins, and other materials. The processes may be either anaerobic or aerobic. Fermentation is often the only financially viable method for manufacturing complex molecules such as enantiomers. There are over 150 companies worldwide employing bacteria, yeast, and fungi in fermentation processes which consist of preparing sterile medium, fermentors, and related equipment; propagation of seed cultures; culturing the microorganisms; separation of the product from the fermentation broth; and subsequent purification. Fermentations, which typically require oxygen, carbon, and nitrogen sources and other nutrients such as raw materials, are computer controlled to provide optimal pH, temperature, oxygen saturation, and nutrient concentrations.
Fertilizers
Authors: Taylor Alan W. 
Published: August 2004

Abstract
The function of fertilizer applications is to raise the level of soil fertility and biological activity in the soils and farming areas where they are used by increasing the amounts of available plant nutrients, in particular, nitrogen and phosphorus. As a result, adverse environmental impacts may occur to water quality. In recent years, there has been a large body of research directed toward the need to reduce the fertilizer contribution to these problems.
Catalyst Regeneration, FCC units
Authors: Upson L. L. , Lomas D. A. 
Published: August 2004

AbstractThe fluid catalytic cracking (FCC) process is an important refinery process in the United States. Catalyst regeneration is an essential part of this process. In the reactor section of a FCC unit, hydrocarbon feed is combined with hot fluidizable cracking catalyst at the base of the riser reactor. Catalyst and hydrocarbon vapors pass up the riser in a dilute‐phase, plug‐type flow and discharge into the reactor vessel where catalyst and hydrocarbon vapors are separated. When in contact with the catalyst, the hydrocarbon feed cracks to form gasoline, middle distillates, liquefied petroleum gas (LPG), and fuel gas. Coke, which is also formed, deposits on the catalyst surface and greatly reduces the catalyst activity. To restore its activity, the catalyst passes into the regenerator section where the coke is burned off. The heat released from coke burning is completely used to provide the heat requirements on the reactor side. Heat balance, environmental concerns, regenerator configuration and design, and other parameters of FCC are discussed.
Formaldehyde
Authors: Gerberich H. Robert , Seaman George C. 
Published: August 2004

AbstractFormaldehyde is a versatile, reactive substance, basic to the chemical industry because of its low cost and ease of production. It is manufactured by vapor‐phase oxidation of methanol using two principal processes. One method employs a pure silver catalyst and the other an iron molybdate catalyst. Several other processes are under development, but none have been commercialized. All processes are capital intensive, requiring integrated reaction, heat recovery, and purification systems to achieve optimum economic benefits.Formaldehyde is sold as concentrated, aqueous solutions, and may contain methanol to inhibit polymerization. It is also sold in alcohol solutions, which contain little water. Its principal uses are in the production of amino and phenolic resins, polyhydric alcohols, acetal resins, paraformaldehyde, and fertilizers. It reacts with numerous organic compounds in condensation‐type reactions, resulting in formation of one or more new carbon‐carbon bonds.In recent years, formaldehyde has come under increased scrutiny because of its potential negative health effects. It is an irritant to the eyes, nose, and throat, and is a suspected human carcinogen.
Initiators, Free‐Radical
Authors: Sanchez José , Myers Terry N. 
Published: August 2004

AbstractMost commercial free‐radical applications employ initiators such as peroxides and azo compounds. Lesser amounts of carbon–carbon initiators and photoinitiators, and high energy ionizing radiation are also used commercially to generate free radicals. The chemical initiators are substances possessing labile oxygen–oxygen, carbon–nitrogen, or carbon–carbon covalent bonds that under certain thermal, chemical, or photochemical conditions undergo homolytic scission of the labile bond to produce free radicals. The free radicals produced are useful in many industrial chain reactions, eg, halogenations, additions to carbon–carbon double bonds, polymerizations of vinyl monomers, grafting reactions, curing of rubbers and unsaturated polymers, cross‐linking of polyolefins, modification of polyolefins, and reactive processing.In this article free‐radical initiator decomposition pathways are reviewed. Initiator reactivity is related to chemical structure and to first‐order decomposition parameters such as temperature, frequency factor, and activation energy. Reactivity of derived free radicals is also related to structure and to the occurrence of secondary reactions such as β‐scission and induced decomposition. The energy and the chemical properties of the free radicals determine commercial utility, thus the interrelation of initiators, their kinetics, and the radicals produced provide guidelines for initiator selection.
Furnaces, Fuel‐Fired
Authors: Bozzuto Carl R. 
Published: August 2004

AbstractA furnace is a device (enclosure) for generating controlled heat with the objective of performing work. In fossil‐fuel furnaces, the work application may be direct (eg, rotary kilns) or indirect (eg, plants for electric power generation). The furnace chamber is either cooled (waterwall enclosure) or not cooled (refractory lining). Furnaces related to metallurgy such as blast furnaces are excluded. Fuel‐fired furnaces primarily utilize carbonaceous or hydrocarbon fuels. Since the purpose of a furnace is to generate heat for some useful application, flame temperature and heat transfer are important aspects of furnace design. Industrial furnaces are an order of magnitude smaller than power‐plant furnaces since the applications are usually on an individual basis rather than feeding power to a regional electric grid. Like the power‐plant furnace, the function of the industrial furnace usually is to generate steam, generally for a chemical process, mechanical power, or heating application, rather than electric power generation. New furnace concepts in evolutionary stages include fluidized‐bed furnaces, coal gasification furnaces, and MHD furnaces. Fluidized‐bed combustion has reached commercial‐scale operations.
Germanium and Germanium Compounds
Authors: Thomas Dennis W. 
Published: August 2004

AbstractGermanium is a semiconducting metalloid element found in Group 14 (IVA), Period 4 of the Periodic Table. Although it looks like a metal, it has a diamond cubic crystal structure and is fragile like glass. Its electrical resistivity is about midway between that of metallic conductors and good electrical insulators. The first significant use was in solid‐state electronics, and, using germanium, the transistor was invented. The entire modern field of semiconductors owes it development to the early successful use of germanium. Germanium is used for optical fiber production, as polymerization catalysts, in infrared optics, in electronic and solar applications, and in other miscellaneous markets. Germanium usually occurs widely dispersed in minerals. Most germanium production has been from zinc smelters and copper smelters.Germanium also occurs in significant concentrations in many coals around the world. Germanium is quite stable in air up to 400°C, where slow oxidation begins. The metal resists concentrated acid and alkali. Many Ge alloys have been prepared and studied.No mineral is mined solely for its germanium content. Almost all of the Ge recovered worldwide is a by‐product of other mining. Germanium compounds generally have a low order of toxicity.