bluuebunny/crossref_metadata_2025_split huggingface dataset:
Butylenes
Authors: Calamur Narasimhan , Carrera Martin E. , Wilsak Richard A. 
Published: August 2004

AbstractButylenes are C4H8mono‐olefin isomers: 1‐butene,cis‐2‐butene,trans‐2‐butene, and isobutylene (2‐methylpropene). These isomers are usually coproduced as a mixture and are commonly referred to as the C‐4 fraction. These C‐4 fractions are usually obtained as by‐products from petroleum refinery and petrochemical complexes that crack petroleum fractions and natural gas liquids. Since the C‐4 fractions almost always contain butanes, it is also known as the B–B stream. The linear isomers are referred to as butenes. The carbon–carbon double bond is the distinguishing feature of the butylenes and, as such, controls their chemistry. The carbon–carbon bond, acting as a substitute, affects the reactivity of the carbon atoms at the alpha positions through the formation of the allylic resonance structure. This structure can stabilize both positive and negative charges. Reactions of butylenes can be divided into two broad categories: those that take place at the double bond itself, destroying the double bond; and those that take place at alpha carbons. The C‐4 isomers are almost always produced commercially as by‐products in a petroleum refiner–petrochemical process. There are other commercial processes available for the production of butylenes. However, these are site‐ or manufacturer‐specific. Any of these processes can become an important source in the future. Several technologies are emerging for the production of isobutylene to meet the expected demand for isobutylene: deep catalytic cracking; superflex catalytic cracking; dehydrogenation of butanes; and the Coastal process of thermal dehydrogenation of butanes. There are four types of separation methods available: selective removal of isobutylene by polymerization and separation of 1‐butene; use of addition reactions with alcohol, acids, or water to selectively produce pure isobutylene and 1‐butene; selective extraction of isobutylene with a liquid solvent, usually an acid; and physical separation of isobutylene from 1‐butene by absorbents. There are three important processes for the production of isobutylene; the extraction process using an acid to separate isobutylene; the dehydration oftert‐butyl alcohol, formed in the Arco's Oxirane process; and the cracking of MTBE. Handling requirements are similar to liquefied petroleum gas (LPG). Butylenes are not toxic. The effect of long‐term exposure is not known; hence, they should be handled with care. They are volatile and asphyxiants. Care should be taken to avoid spills because they are extremely flammable.
Carbonyls
Authors: Wagner Frank S. , Kaesz Herbert D. 
Published: August 2004

AbstractCarbon monoxide forms a host of metal carbonyl complexes, at least one for every transition metal. Mononuclear, polynuclear, and heteronuclear metal carbonyls are all known. The complexes, of general formula Mx(CO)y, may be charged or neutral; the metal or metals are in the zero oxidation state. Metal carbonyls are useful as reagents and catalysts in organic synthesis, and play a role in both the Reppe and the oxo processes, as well as in the preparation of synthetic fuels and in vapor deposition of purified metals.The structure and bonding of the metal carbonyls, including that of cluster compounds, follow well‐defined rules. Synthesis of the metal carbonyls usually proceeds either from the reduction of the corresponding metal, initially in the form of a metallic salt, or via condensation of lower molecular weight compounds.
Cellulose
Authors: French Alfred D. , Bertoniere Noelie R. , Battista O. A. , Cuculo John A. , Gray Derek G. 
Published: August 2004

AbstractThis article covers nomenclature, sources, preparation, uses, microcrystalline cellulose, structural chemistry, reactions, solvents, and liquid crystals. Cellulose for commercial purposes comes mostly from wood and cotton, whereas cellulose for research comes from bacteria, algae, and ramie (also a textile fiber). Preparation includes pulping and purification, with a new alternative method of steam explosion. The pore structure of cellulose is mentioned, along with the build‐up of cellulose molecules into entire fibers. Emphasis is given to cellulose crystal structure, where recent research on the dominant natural form has made previous findings obsolete. Most cellulose is a mixture of two crystalline phases. Cellulose solutions are important to the rayon and cellophane industries, and new solvents are of interest because they may lessen pollution and might permit commercial production of stronger cellulosic materials through the formation of liquid crystals. Figures include the chemical and physical structures of the molecule, including in solution, the structure of a microfibril, and the unit cell structures of Cellulose I‐IV.
Cesium and Cesium Compounds
Authors: Burt Richard O. 
Published: August 2004

AbstractCesium is the most chemically active and rare of the naturally occurring Group 1 (IA) alkali metals. It is generally produced from pollucite by acid digestion to an intermediate cesium compound followed by thermochemical or electrolytic reduction. Production routes and properties of cesium and cesium compounds are described. Uses of cesium and cesium compounds continue to grow in electronics, in catalysts and organic synthesis, in analytical instrumentation, and in biotechnology. Cesium usage has also shown potential in such areas as magnetohydrodynamic power generation.
Chocolate and Cocoa
Authors: Zoumas B. L. , Smullen J. F. 
Published: August 2004

Abstract
Most chocolate and cocoa products consist of blends of roasted cocoa beans chosen for flavor and color characteristics. Cocoa may be blended in the bean, nib, or liquor state before going on to the chocolate making or pressing phase. Pressing separates the liquor into cocoa powder and cocoa butter, approximately 50:50.
The ingredients used for making chocolate are cocoa liquor, cocoa butter, sugar, and flavor for dark chocolate, plus milk for milk chocolate. These ingredients are mixed and then refined so the particle size of the ingredients is reduced to make the resultant chocolate smooth.
After refining, the chocolate is conched during which changes to viscosity, flavor, and texture occur. After conching, the product is standardized to fat content and viscosity, is tempered to obtain the correct form of fat crystal, and is deposited into molds to form the final shape. The chocolate is removed from the molds after cooling and then is wrapped and packaged ready for shipment to the customer.
Colloids
Authors: Bleier Alan 
Published: August 2004

AbstractA colloid is a finely dispersed material, having a high surface‐area‐to‐volume ratio. It is usually a solid particle, but it may be a liquid droplet or a gas bubble. The differences in composition, structure, and interactions between the surface atoms or molecules and those on the interior impart colloids with diverse physicochemical properties that generally deviate from those of both the constituent atoms or molecules and the macroscopic material.Many technological problems relate to the behavior of colloids, especially those dispersed in a liquid or gaseous fluid. Commercial examples include metals, magnetic powders, catalysts, ceramics, minerals, oil recovery, technical glasses, paints and pigments, polymers, pulp and paper, prepared foods, pharmaceuticals, fibers, detergents, and purified water. Natural and biological systems can also depend on the behavior of colloids, and soil science and plant nutrition, meteorology, hematology, membrane science, and medical technology furnish numerous examples. Thus the ubiquity and importance of colloids have made the ability to control their formation, destruction, or stabilization a critical problem, irrespective of whether the colloidal material is deemed desirable or undesirable.This article addresses the physical and chemical properties of colloidal materials, their widespread applications, and the hazards associated with finely dispersed particulates.
Colorants for Ceramics
Authors: Eppler Rchard A. 
Published: August 2004

AbstractCeramics may be colored by melting a transition metal into a glass or dispersing it in a ceramic body, by precipitating a colored crystal in a transparent matrix, or by dispersing in a matrix an insoluble crystal or crystals that are colored. The latter is the principal method of coloration of ceramic coatings. Most of the crystals used for ceramic pigments are complex oxides. The choices to obtain the principal colors are described in this article. Also discussed are the factors to be considered in selecting a ceramic pigment: processing stability requirements, pigment uniformity and reproducibility, particle size distribution, dispersibility, and compatibility of all materials to be used.
Dimethylacetamide
Authors: Watts J. C. , Larson P. A. 
Published: August 2004

Abstract

Dimethylacetamide, DMAC, mol wt 87.12, CH
3
CON (CH
3
)
2
, is a colorless, high boiling polar solvent. DMAC is a good solvent for a wide range of organic and inorganic compounds. The polar nature of DMAC enables it to act as a combined solvent and reaction catalyst, often producing high yields in short time periods. The chemical reactions of DMAC are typical of those of disubstituted amides. Dimethylacetamide can be produced by the reaction of acetic acid and dimethylamine, or by the reaction of acetic anhydride and dimethylamine. DMAC is capable of producing systemic injury, principally cumulative damage to the liver and kidney, when repeatedly inhaled or absorbed through the skin. The uses of dimethylacetamide are very similar to those for dimethylformamide.
Dyes, Anthraquinone
Authors: Hattori Makoto 
Published: August 2004

AbstractThe history and current situation of the anthraquinone dye industry, and basic chemistry of anthraquinone compounds (color and structure, and general method of synthesis) are discussed. The manufacturing processes of key intermediates are illustrated both on the basis of industrial importance and the latest advances in research and development. Emphasis is placed on process improvements in view of environmental issues.The properties and the preparation of anthraquinone dyes are discussed according to dye type: reactive dyes (bromamine acid derivatives with sulfatoethylsulfonyl, chlorotriazine, and other heterocyclic functional group), disperse dyes (1‐amino‐4‐hydroxy‐anthraquinones, 1,4‐diaminoanthraquinone‐2,3‐dicarboxyimides, 1,4,5,8‐substituted anthraquinones, 1,4‐diaminoanthraquinones, andN‐substituted‐1‐amino‐4‐hydroxyanthraquinones), acid dyes (bromamine acid derivatives and quinizarin derivatives), vat dyes (benzanthrones, indanthrones, anthrimides, anthrimidocarbazoles, acylaminoanthraquinones, anthraquinoneazoles, anthraquinone acridones, anthrapyrimidines, and other highly condensed ring systems), and mordant dyes. Recent advances in functional dyes related to the electronics industry are also presented. Economic aspects of the anthraquinone dye industry are included and health and safety information is presented.
Chromogenic Materials, Electrochromic
Authors: Greenberg Charles B. 
Published: August 2004

AbstractElectrochromism is a reversible color change in a material, often a thin film, that accompanies an oxidation‐reduction reaction driven by a small current at low voltage. It occurs at or near room temperature in both cathodically colored and anodically colored inorganic and organic compounds. It is accompanied by ion insertion/extraction (doping/undoping) for charge balance in thin solid films. Electrochromic chromogenic materials are divided into two groups based on whether or not insertion/extraction occurs or is distinguishing. For the smaller, noninsertion group, reversible coloration occurs in solution or is associated with reversible electrodeposition from solution. The best known members are viologens.There are three subsets of the insertion/extraction group: (1) cathodically colored inorganic materials usually color with either H+or alkali‐ion insertion. The best known film is amorphous tungsten oxide, in part because of its relatively high coloration efficiency in the visible region; (2) anodically colored inorganic materials include Prussian blue, also having a high coloration efficiency, and hydrated oxides of iridium and nickel. Often, K+is inserted for Prussian blue. There is a lively debate about whether H+or OH−is active for the hydrated oxides; (3) doped/undoped organic films color both anodically and cathodically, in general. There is must less known about this form of electrochromism in literature which, as a whole, has been reviewed through 1990.
Esters, Organic
Authors: Tau Kwoliang D. , Elango Varadaraj , McDonough Joseph A. 
Published: August 2004

AbstractThis article presents important information related to carboxylic esters including nomenclature, physical properties, chemical reactions, occurrence and preparation, analysis, health and safety issues, handling regulations, and commercial uses. It also includes figures for United States production and sales of carboxylic esters in 1990.Chemical reactions of esters discussed are hydrolysis (acidic, basic, steam, and enzymatic), transesterification, ammonolysis and aminolysis, reduction (catalytic and stoichiometric), enolate reactions, Grignard and related reactions, acyloin condensation, pyrolysis, substitution, alkylation, and rearrangement.Analytical methods for characterization as well as spectral behavior of esters are given. Discussion on health, safety, and handling focuses on ester's reactivity, flash point, autoignition temperature, toxicity data, and permissible exposure limits.Uses of esters in areas such as solvents, plasticizers, resins, plastics, coatings, lubricants, perfumes, flavors, cosmetics, soap, surface‐active agents, medicinals, herbicides, and pesticides are described. Some specific examples are also given.
Ethers
Authors: Karas Lawrence , Piel W. J. 
Published: August 2004

Abstract
An overview of ethers is provided that covers the general types of ethers, their synthesis reactions, properties, and some general uses in industry. More detail and expanded discussion is provided on ethyl ether, tetrahydrofuran (THF), and methyl tertiary butyl ether (MTBE), which represent three of the ethers with the highest commercial volumes. One of the fastest growing and largest uses of ethers is for gasoline blending. Though initially developed to provide octane in gasoline, fuel‐grade ethers are now used to add oxygen to the gasoline mixture, which helps improve combustion and reduce tailpipe emissions from automobiles. Besides MTBE, other possible fuel ethers such as ethyl tertiary butyl ether (ETBE) and tertiary amyl ether (TAME) are also noted.
Fluorine
Authors: Shia George 
Published: August 2004

AbstractFluorine, the first member of the halogen family, is the most reactive nonmetal, and capable of reacting with all of the other elements, except the gases helium, neon, and argon, oxidizing most elements to their highest oxidation. Although fluorine is highly corrosive, commercial uses have been developed. The largest industrial usage for fluorine is in the production of uranium hexafluoride, which is used in the uranium enrichment process, and in the production of sulfur hexafluoride, a gaseous dielectric. Fluorine is also used to make perfluorinated materials and for surface treatment of polyolefin‐based containers.Fluorine is produced by electrolysis of molten potassium bifluoride in specially designed cells having steel or Monel cathodes and carbon anodes. The selection of the anode carbon is critical. This manufacturing process and the special equipment needed for handling fluorine are described. Most fluorine produced is used captively for synthesis.
Coal Conversion Processes, Gasification
Authors: Mahagaokar Uday , Krewinghaus A. B. 
Published: August 2004

Abstract
Coal gasification is a well‐proven technology that provides an excellent way to utilize vast resources of coal efficiently and cleanly. The near‐term application of coal gasification is in conjunction with combined cycle systems to generate electricity. Modern coal gasification processes produce high pressure syngas, which can be fed as fuel to a gas turbine. The high efficiency derived from combining gas turbine cycles with steam turbine cycles, along with significant environmental benefits, makes coal gasification combined cycle (CGCC) power plants more attractive than conventional technologies that generate power by coal combustion.
Gasification technologies are described for various types of feedstocks. The chemistry of coal gasification is presented and process results are shown for several coals with a focus on gasifier performance and process efficiency. Other potential applications of coal involve the use of syngas chemistry to produce chemicals.
Gelatin
Authors: Keenan Thomas R. 
Published: August 2004

Abstract
Gelatin is a protein obtained by partial hydrolysis of collagen, the chief protein component in skin, bones, hides, and white connective tissues of the animal body. Type A gelatin is produced by acid processing of collagenous raw material; type B is produced by alkaline or lime processing. Because it is obtained from collagen by a controlled partial hydrolysis and does not exist in nature, gelatin is classified as a derived protein.
Uses of gelatin are based on its combination of properties; reversible gel‐to‐sol transition of aqueous solution; viscosity of warm aqueous solutions; ability to act as a protective colloid; water permeability; and insolubility in cold water, but complete solubility in hot water. It is also nutritious. These properties are utilized in the food, pharmaceutical, and photographic industries. In addition, gelatin forms strong, uniform, clear, moderately flexible coatings which readily swell and absorb water and are ideal for the manufacture of photographic films and pharmaceutical capsules.
Acetic Acid, Halogenated Derivatives
Authors: Morris Earl D. , Bost John C. 
Published: August 2004

AbstractThe most important of the halogenated derivatives of acetic acid is chloroacetic acid, which has wide applications as an industrial chemical intermediate in the manufacture of cellulose ethers, herbicides, and thioglycolic acid. Most chloroacetic acid is produced by the chlorination of acetic acid. Chloroacetic acid is extremely corrosive and will cause serious chemical burns, and is readily absorbed through the skin; contamination of 5–10% of the skin is usually fatal. Sodium chloroacetate, C2H2ClO2Na, is produced by reaction of chloroacetic acid with sodium hydroxide or sodium carbonate. Dichloroacetic acid, C2H2Cl2O2, is a reactive intermediate in organic synthesis. It has been manufactured by the chlorination of acetic and chloroacetic acids and by other means. Trichloroacetic acid, C2HCl3O2, forms white deliquescent crystals. Sodium trichloroacetate, C2Cl3O2Na, is used as a herbicide. Chloroacetyl chloride (ClCH2COCl) is the corresponding acid chloride of chloroacetic acid, and is manufactured by reaction of chloroacetic acid with chlorinating agents. Much of the chloroacetyl chloride produced is used captively as a reactive intermediate. It is useful in many acylation reactions and in the production of adrenalin, diazepam, and chloroacetic anhydride. Two chloroacetate esters of industrial importance are methyl chloroacetate, C3H5ClO2, and ethyl chloroacetate, C4H7ClO2. Both are used as agricultural and pharmaceutical intermediates. Other derivatives are bromoacetic acid, dibromoacetic acid, tribromoacetic acid, iodoacetic acid, diiodoacetic acid, and triiodoacetic acid.
Hazard Analysis and Risk Assessment
Authors: Crowl Daniel A. 
Published: August 2004

Abstract

The purpose of hazard analysis and risk assessment in the chemical process industry is to
(1)
characterize the hazards associated with a chemical facility;
(2)
determine how these hazards can result in an accident; and
(3)
determine the risk, ie, the probability and the consequence of these hazards. Methods for performing hazard analysis and risk assessment include safety review, checklists, Dow Fire and Explosion Index, what‐if analysis, hazard and operability analysis (HAZOP), failure modes and effects analysis (FMEA), fault tree analysis, and event tree analysis.

In order to complete an assessment of risk, a probability must be determined.
A more recent concept which could have significant impact on future designs is that of inherent safety. Hazard avoidance is performed by three techniques. First, there is substitution. This means substituting a less hazardous material for the material in use. The second method for inherent safety is attenuation, ie, operating the process at lower temperatures and pressures. The last inherent safety technique is intensification. This means using much smaller inventories of hazardous raw and intermediate materials, and reducing process hold‐up and inventories.
Insect Control Technology
Authors: Metcalf Robert L. 
Published: August 2004

AbstractInsects are the most numerous of living organisms and the nearly one million described species constitute approximately 72% of all animal species. Of these about 1% are considered significant pests. This article summarizes the chemistry, properties, uses, and advantages and disadvantages of most of the chemicals used for insect control. These include many products of largely historical interest as well as some not registered for use in the United States but used elsewhere in the world.Approximately 70% of all insecticide use is in agriculture and applications are generally made directly to raw agricultural commodities to protect plants and animals from insect attacks. With the exception of microbial insecticides, nearly all of the uses of insecticides result in residues of the various chemicals and their degradation products.Basic guidelines for the limitations of pesticide residues in raw agricultural commodities are established by national and international agencies. International standardization is highly desirable for trade in foodstuffs and values for more than 100 pesticides used on more than 1600 specified food crops are reviewed periodically. Vol. 14, pp. 524–602, 77 refs. to 1993.
Furnaces, Electric, Introduction
Authors: Sommer Richard A. 
Published: August 2004

Abstract
Furnaces, Electric, Introduction. Richard A. Sommer (Consultant). The term electric furnace applies to all furnaces that use electrical energy as their sole source of heat. Electric furnaces are used for heating solid materials to desired temperatures below their melting points for subsequent processing, or melting materials for subsequent casting into desired shapes. Classification is by the manner in which the electrical energy is converted into heat. Three types of furnaces are widely used in industry: electric resistance furnaces, arc furnaces, and electric induction furnaces.