bluuebunny/crossref_metadata_2025_split huggingface dataset:
Chocolate and Cocoa
Authors: Zoumas B. L. , Azzara C. D. , Bouzas J. 
Published: July 2004

AbstractMost 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, ∼ 50:50.The ingredients used for making chocolate are cocoa liquor, cocoa butter, sugar, lecithin, and vanillin for dark chocolate, plus milk solids 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.
Choline
Authors: Gidding Curtis E. 
Published: July 2004

AbstractThe quaternary ammonium compound choline or a precursor is needed in the diet as a constituent of certain phospholipids (lecithin) universally present in protoplasm. This makes choline an important nutritional substance. It is also of great physiological interest because one of its esters, acetylcholine, appears to be responsible for the mediation of parasympathetic nerve impulses and has been postulated to be essential to the transmission of impulses of all nerves. Acetylcholine and other more stable compounds that simulate its action are pharmacologically important because of their powerful effect on the heart and on smooth muscle. Choline is used clinically in liver disorders. Its principal commercial use is as a constituent in animal feeds usually as the chloride.Choline's properties, biological functions, occurrence, preparation, analysis, and uses are discussed. Some of its salts and derivatives are also described.
Chromium Compounds
Authors: Page Billie J. , Loar Gary W. ,   Updated by Staff
Published: July 2004

AbstractChromium compounds and their important uses are described. Chemical properties of the low valence compounds, Cr(‐II) through Cr(I), and those of Cr(IV) and Cr(V) are discussed as are those of the commercially important oxidation states of Cr(II), Cr(III), and Cr(VI).Sodium chromate and dichromate production from imported chromite ore, and the production of other chromates, dichromates, and chromic acid are summarized. The manufacture of water‐soluble trivalent compounds is also given. Regulations concerning shipments, specifications, and analytical test methods are discussed as are the health and safety factors of chromium compounds.The environmental impact and waste management practices of chromium compounds is also of importance. Chromium compounds of various oxidation states are used commercially as pigments, in metal finishing, leather tanning, drilling muds, and in wood preservation. Chromium compounds are also used in alloys, batteries catalysts, photosensitive gels, and as reagent grade chemicals.
Coal Conversion Processes, Cleaning and Desulfurization
Authors: Chiang Shiao‐Hung , Cobb James T. 
Published: July 2004

AbstractAn overview of coal cleaning and desulfurization schemes designed to minimize contaminants from coal combustion systems is presented. Coal cleaning can be divided into two basic categories: physical and chemical processes. Physical cleaning involves specific gravity‐controlled processes. Surface‐force‐controlled processes, such as flotation and selective agglomeration, dominate newer developments. Whereas chemical and biological coal cleaning processes have shown potential to produce deep‐cleaned coal, most of these processes have yet to be tested at commercial scale.As coal is burned, and also following combustion, sulfur dioxide can be removed at a number of locations as the combustion gas gives up its heat and entrained particulate matter before being exhausted to the atmosphere. Atmospheric and circulating fluidized‐bed combustors are commercially available, and pressurized fluidized‐bed combustors are being developed to collect sulfur dioxide in limestone injected into the combustion zone. Limestone injection just after combustion in a pulverized coal furnace, and processes whereby lime or limestone can be injected into the ductwork following the boiler and in dry scrubbers for desulfurization, have been installed at coal‐fired power plants and these and both wet and dry regenerable scrubbers are described.
Metal Surface Treatments, Cleaning
Authors: Murphy Donald P. 
Published: July 2004

Abstract
Metal surface cleaning is the beginning of any metal treatment. The cleaners for metal surfaces may be classified as solvent‐based or aqueous. Usage of solvent‐based cleaners is declining. Whereas aqueous cleaners may be acidic, neutral, or alkaline, alkaline cleaners are the most widely used. The types of components typically found in an alkaline cleaner for specific types of metals or alloys, together with cleaning temperatures and other conditions of operation, are discussed. The most common mechanisms of soil removal are presented, as well as descriptions of the various cleaner application methods such as spray, immersion, electro‐ and barrel cleaning.
Coatings, Marine
Authors: Brady Robert F. , Drisko Richard W. 
Published: July 2004

AbstractMarine coatings technology and the role of marine coatings in controlling corrosion are described. Marine coatings aid in the prevention of corrosion of ships, buoys, offshore drilling platforms, piers, locks, and bridges. These coatings impart surface properties, such as fouling protection, which cannot be attained by any other means. Regulations concerning coatings materials and surface preparation methods are summarized. The principal types of modern marine coatings, surface preparation methods, and application techniques are described, advantages and drawbacks are specified, and criteria for selection and use are given. Coating components such as pigment, resins, and additives are provided. The performance requirements for coatings in various ship areas are identified, and the coatings which meet these requirements are described.
Coffee
Authors: Wasserman Gerald S. , Bradbury Allan , Cruz Theodore , Penson Simon 
Published: July 2004

AbstractThis article presents a description of coffee processing technology; coffee chemistry and coffee consumption trends. Special attention is given to green coffee processing, the chemistry of green coffee, the effects of roasting and brewing upon chemistry, as well as the chemistry of instant or soluble coffee. Processing and packaging of roasted, ground, instant and decaffeinated coffees are discussed. The economics of green coffee, as well as the import and world production figures for 1999–2000, are included. Emerging activity in coffee biotechnology is also discussed.
Colloids
Authors: Schramm Laurier L. 
Published: July 2004

AbstractA colloid comprises a collection of small particles, droplets, or bubbles of one phase having at least one dimension between ∼ 1 and 1000 nm, and dispersed in a second phase. Either or both phases may be in gas, liquid, solid, or supercritical phase states. Another property that distinguishes colloidal dispersions is the extremely large area of the interface between the two phases compared with the mass of the dispersed phase. A consequence is that any chemical and physical phenomena that depend on the existence of an interface become very prominent in colloidal dispersions. Colloidal systems are important because they feature prominently, in both desirable and undesirable contexts, in a wide variety of practical disciplines, products and industrial processes. The problems associated with colloids are usually interdisciplinary in nature and a broad scientific base is required to understand them completely. This article provides an introduction to the field of colloids, emphasizing the wide range of practical and industrial applications.
Colorants for Plastics
Authors: Charvat Robert A. 
Published: July 2004

Abstract
Colorants in plastic consumer and industrial products play a major role in their acceptance by the consumer. Color is what sells the product to the consumer. Industrially, color plays an important role in identifying parts, as an example. What a dull world it would be without color! Coloring a product correctly, however, is not an easy task. Years ago, the coloring of materials was a true art. Today, the art is still there, but science now plays a much greater role.
Colorants are generally classified into three distinct groups: organic pigments, inorganic pigments, and soluble dyes. These three major groups are available in a number different physical forms designed to maximize their effectiveness and efficiency of use. Each is quite different in how it brings color to a product and how they may affect other properties not visible, which could make a product more effective. Colorants and other additives for that matter can positively and/or negatively effect such properties as strength, impact resistance, electrical properties, opacity–transparency processing parameters, durability to heat, chemical attack and weathering if the product is destined for outdoor use.
Combustion Science and Technology
Authors: Sharifi Reza , Pisupati Sarma V. , Scaroni Alan W. 
Published: July 2004

AbstractIn the introductory section, some of the fundamental concepts and theories of combustion science such as higher heating value of fuel, air to fuel ratio, flammability limits, ignition, and flame temperature are discussed. Premixed and diffusion flames are then defined and some guidelines for their analysis and understanding are outlined. Finally, the fundamentals of coal combustion are discussed. Then the technology involved in the combustion of the three most common types of fossil fuels, namely gas, oil, and coal, is discussed along with some design parameters for the combustion chambers. The most recent advances in fossil fuel combustion technology are pointed out and some of the associated problems with each fuel are explained. Finally, the impact of fossil fuels on the environment and some of the techniques available for reducing their impact are pointed out.
Boron Hydrides, Heteroboranes, and their Metalla Derivatives (Commercial Aspects)
Authors: Barendt Joseph , Dryden Beth 
Published: July 2004

AbstractSodium tetrahydroborate, NaBH4, more commonly called sodium borohydride, is the most widely used commercial boron hydride. Sodium borohydride is available as a 12% solution in caustic soda and in solid form either as powder or pellets. Solid sodium borohydride does not ignite upon contact with moisture and is not shock‐sensitive. These characteristics allow it to be handled safely in air. Because it does liberate hydrogen upon contact with water it should be handled with care. The predominant use for sodium borohydride is in wood pulp bleaching. The next largest commercial use is as a reducing agent of functional groups in organic synthesis. A significant application in pharmaceutical synthesis is the stereospecific and selective reduction in steroid production. Borane complexes are the most widely used commercial boron compounds, after sodium borohydride. Examples used in organic synthesis are amine borane complexes and borane complexes of tetrahydrofuran and dimethyl sulfide. Although not commercial as yet, boron neutron capture therapy (bnct) involves the uptake of boron compounds enriched with the boron‐10,10B, isotope, selectively accumulating in cancerous tumors.
Semiconductors, Compound Semiconductors
Authors: Drummond Timothy J. , Biefeld Robert M. , Sherwin Marc E. , Crawford Mary H. 
Published: July 2004

Abstract
The term compound semiconductor encompasses a large number of materials, most of which crystallize in either the zincblende, wurtzite, or rock salt crystal structures. This article focuses primarily on the properties of the most extensively studied Groups III and V and Groups (2, 12) II–VI compound semiconductors. A summary of the physical (mechanical and electrical) properties of the zincblende cubic semiconductors, a description of the metal organic chemical vapor deposition process, the physics and applications of electronic and photonic devices, and the fabrication process technology in use to create both electronic and photonic devices and circuits are discussed.
Computer‐Aided Design and Manufacturing (CAD/CAM)
Authors: Pao Y. C. , Clements L. D. 
Published: July 2004

Abstract
Design has a long history but computer‐aided design (CAD) offers a new, modern connotation. With the exception of the physical processes, such as cutting, forging, and mixing used to a manufacture items, the commonly discussed topics in computer‐aided manufacturing (CAM), such as material planning, process and procedure designs, numerical control, and scheduling, can also be considered CAD because design is involved. This article reviews the history of computer‐aided design beginning with ENIAC, the first electronic computer, which was developed for the army during World War II, through the recent introduction of a computer that has a speed of 100–250 million floating‐point operations per second (flops). In automating chemical processes and computations, companies must decide whether to use commercial software packages or to develop in‐house CAD/CAM programs. Many of the underlying principles employed in the design of the prevailing commercial software packages are discussed. These principles can also guide the development of in‐house programs. The topics covered include absorption to waste management, and range from drafting isometric pipeline systems and the interactive manipulation of block diagrams involved in chemical processes to the solid modeling of molecular structures.
Petroleum, Composition
Authors: Robbins Winston K. , Hsu Chang Samuel 
Published: July 2004

Abstract
Petroleum is a complex mixture, consisting primarily of hydrocarbons, derived from ancient living organisms deposited as geological sediments. The composition of petroleum conveniently described in terms of refinery distillation varies greatly from one source to another. The naphtha, middle‐distillate, vacuum gas oil, and vacuum resid fractions increase in complexity and molecular weight. The elemental and molecular composition of these fractions show a general shift from simple saturated hydrocarbons in the naphtha to more complex aromatics and eventually sulfur‐, nitrogen‐, and oxygen‐containing hydrocarbons in the heavier distillates. The nondistillable vacuum resid includes still larger molecules that appear to contain several groups of the benzologues of smaller molecular structures linked together plus the largest portion of the S, N, O, and metal compounds. Complete compositional analysis of petroleum is possible only for low boiling fractions. For high boiling fractions, composition is usually determined by compound types and carbon number ranges. For nonvolatile fractions, only average structure can be obtained. Elaborate separation into well‐defined fractions can aid in compositional analysis by sophisticated analytical techniques.
Noble‐Gas Compounds
Authors: Schrobilgen Gary J. , Moran Matthew D. 
Published: July 2004

AbstractNoble‐gas reactivity was discovered in 1962 when Neil Bartlett showed that xenon gas was oxidized by PtF6to XePtF6. Pursuant to his discovery, numerous xenon and krypton compounds were synthesized in macroscopic quantities. Among the noble‐gas elements, xenon has the most extensive chemistry, and can possess formal oxidation states of 0, +½, +2, +4, +6 and +8 in its compounds by forming fluorides, oxides and oxide fluorides as well as derivatives in which xenon is bonded to polyatomic groups through oxygen, nitrogen and carbon. In addition, several compounds containing Xe‐Au bonds and one compound containing an Xe‐Xe bond are known. Other xenon‐element bonds are known in the gas phase or in low‐temperature matrices, which provide examples of Xe‐H, Xe‐Si, Xe‐S, Xe‐X (X = Cl, Br, I) and Xe‐U bonds. Krypton chemistry is more limited. Only compounds with krypton in the +2 oxidation state are known, namely, KrF2, salts of the KrF+and Kr2F3+cations, by analogy with xenon, Kr(OTeF5)2and several species containing Kr‐N bonds. Several gas‐phase and matrix‐isolated species in which krypton is bonded to carbon, hydrogen and halides other than fluorine are also known. Radon is believed to form RnF2and RnF+by analogy with krypton and xenon. The only argon species that are known are the ArF+cation, which has been observed in the gas phase, and HArF, which has been stabilized in a low‐temperature argon matrix. To date, no argon, neon or helium compounds have been isolated in macroscopic amounts. Noble‐gas compounds have been utilized as oxidizers and oxidative fluorinating agents in chemical syntheses.
Computer‐Aided Chemical Engineering
Authors: Johns W. R. 
Published: July 2004

AbstractComputer‐Aided Chemical Engineering is reviewed from its beginnings in the 1950s to the present state in which virtually all chemical engineering is computer‐aided. Over 200 computer‐based computations routinely undertaken by chemical engineers are listed. Computer‐aids are used at every stage from deciding what chemical species to make, through the conceptual design of the processes, the detailed design, the on‐line control, optimization and retrofit design, up to the decommissioning. Computer‐aids are important for assessing and minimizing environmental impacts and hazards. This chapter does not discuss any of these topics in detail. It concentrates on the design of reliable software and the correct use of software supplied by third parties. Guidance is given for designing software that properly meets the technical requirements of the end users. The program structure and test procedures necessary to validate the software are described. Methods for ensuring that the program properly incorporates the physical models on which it is based are outlined including emphasis on dimensionally consistent programming. The importance of data validation is emphasized. It is further emphasized that these design guidelines apply equally to models written in special‐purpose modeling systems as they do to models written in general‐purpose computer‐programming languages. The elements of numerical analysis are introduced and illustrated with common examples from chemical engineering. Even simple computations, such as log–mean temperature difference, can be grossly in error if the numerical limitations of computers are ignored. Reliable, easily solved models should be near‐linear and explicit, and steps to achieve such models are included. The treatment is designed to be adequate for engineers writing small programs, or small parts of larger programs. References are introduced to enable professional engineering programmers to pursue the topics in greater depth.End‐users of chemical engineering software have responsibility for the decisions taken based on computed results. They must ensure that the software is adequate for its purpose, that all data is properly validated, and that the computed results are properly interpreted. They are also responsible for scoping the uncertainties in the computation and assessing their impact on the decisions taken. This chapter describes the steps that should be taken to ensure that computer aids are properly used and decisions are properly reached. It gives further reading for engineers likely to manage projects in which extensive use is made of computer tools.A brief introduction is given to some of the rapidly advancing areas of computer‐aided chemical engineering.
Computer Technology
Authors: Watson Ian 
Published: July 2004

Abstract
Computers are an integral part of modern chemistry. As computers have become faster, less expensive, and more functional, chemists have come to rely more and more on their use. These trends are expected to continue. This article provides brief overviews of the principal classes of computers commonly used in chemistry today, together with some of the roles they play. Within each class, there is discussion of the historical significance and changing role of the computer for chemistry. Emphasis is on computers that find application in computational chemistry and other numerically intensive areas. Given the rapidly accelerating rates of change in computer technology, it is expected that this article will provide mostly a historical perspective soon after its publication.
Contraceptives
Authors: Hahn D. W. , McGuire J. L. , Bialy Gabriel 
Published: July 2004

AbstractMillions of people throughout the world use a variety of methods to regulate human fertility, including oral contraceptives, sterilization, vaginal and barrier contraceptives, long‐acting injectable and implantable contraceptives, intrauterine devices, and natural family planning. Each of these methods has its advantages and disadvantages, and contraceptive use varies significantly by country and geographical region. It is generally accepted that none of these methods represents the ideal method of fertility regulation for everyone, and research is focused on new methods such as contraceptive vaccines, GnRH analogues, and progesterone antagonists in many countries throughout the world today.