bluuebunny/crossref_metadata_2025_split huggingface dataset:
Medical Imaging Technology
Authors: Hornak Joseph P. 
Published: July 2004

AbstractMedical imaging is the component of the emerging discipline called imaging science and is concerned with the application of nonsurgical techniques to produce images of the organs and tissues inside the human body. The many technologies applied to produce medical images take advantage of the basic imaging principles of absorption, emission, and reflection of energy by tissues. The principal medical imaging modalities include endoscopy, x‐ray imaging, magnetic resonance imaging, ultrasound imaging, and nuclear imaging. These technologies have extended the frontiers of medicine into areas such as mapping brain function. Technological advances in computers, electronics, and magnetics have aided in the development of medical imaging. The theory and specialized equipment of each technique is presented. Application and safety issues are addressed.
Memory‐Enhancing Drugs
Authors: Zaczek Robert , Chorvat Robert J. 
Published: July 2004

AbstractWhereas memory enhancement can be viewed as generally beneficial to many individuals, agents being developed are almost exclusively for some form of impairment. The memory‐enhancing drugs therapeutically available offer only symptomatic relief rather than slowing or stopping the progression of dementia. The greatest effort in development has been in the areas of cerebral metabolism and neurotransmission enhancers. Cerebral vasodilators and nootropics have both been developed for usage, as have cholinergic enhancers.
Mercury
Authors: DeVito Stephen C. 
Published: July 2004

Abstract
DeVito, Stephen C. (U.S. Environmental Protection Agency). Mercury, used for centuries in many industrial and consumer applications and products because of the unique physical and chemical properties of the metal, is defined as being a hazardous material. The toxic effects of the metal to workers and to the general population as a result of occupational exposure, consumer exposure, and environmental pollution have gained worldwide attention in the last part of the twentieth century. Much effort has been devoted to limiting the production and use of mercury, and finding alternative technologies that are designed to supplant the need for mercury. Overall demand for mercury has decreased throughout the industrialized world and it is likely to continue to decline. The chemistry, properties, natural occurrence, production, processing, economic aspects, environmental releases, uses, and toxicity of mercury are reviewed. Regulatory restrictions imposed by the U.S. Environmental Protection Agency on the production, use, and disposal of the metal are also provided. Vol. 16, pp. 212–228, 45 refs. to June 1993.
Metal‐Matrix Composites
Authors: Chawla Krishan K. , Chawla N. 
Published: July 2004

Abstract
Metal‐matrix composites have a metal or an alloy as the continuous phase, in which the reinforcing phase (particle whisker, short or continuous fiber) is distributed. Important techniques for processing metal‐matrix composites are described. Description of the reinforcement/matrix interface region and its characteristics, and properties of different metal‐matrix composites are provided. Different applications of metal‐matrix composites are summarized.
Methacrylic Acid and Derivatives
Authors: Wilczynski Robert , Jerrick Juliette Jamie 
Published: July 2004

AbstractMethacrylic acid (MAA) and its derivatives exhibit a rich array of chemistries and have found wide use in commercial applications, especially as monomers for making various types of polymer products. The predominant manufacturing route to the two simplest methacrylates continues to be via the conversion of acetonecyanohydrin (ACH) in sulfuric acid to methacrylamide followed by either hydrolysis to MAA or esterification with methanol to give methyl methacrylate (MMA). Alternative routes have reached or are now approaching commercialization. These include processes based on either ethylene (C‐2), propylene (C‐3), methylacetylene (C‐3), or isobutylene (C‐4) feedstocks, as well as a separate ACH process which does not involve sulfuric acid. The later route, which starts with catalyzed hydration of ACH to hydroxyisobutyramide followed by esterification and dehydration steps to MMA, has an added benefit of recycling HCN as a raw material. The ethylene‐based routes typically involve formaldehyde condensation on either a propionaldehyde or propionic acid intermediate. The isobutylene‐based routes involve oxidation processes to reach the methacrylate backbone, often passing through methacrolein as an intermediate. The propylene‐based routes typically involve isobutyric acid or isobutyraldehyde intermediates. The methylacetylene‐based process appears to be the most selective overall, where a single reaction with carbon monoxide and methanol leads directly to MMA. All of the synthetic routes require various types of catalysts to promote the separate steps involved. In addition to providing more details on each of these processes, the following article also provides information on volumes, costs, health and safety for methacrylic acid and its derivatives.
Methylene Chloride
Authors: Holbrook Michael T. 
Published: July 2004

AbstractMethylene chloride is a colorless, heavy liquid with a pleasant ethereal odor. Its outstanding solvent properties are the basis of its principal industrial interest. It is produced almost exclusively by the chlorination of lesser chlorinated methanes along with coproducts chloroform and carbon tetrachloride. U.S. capacity has been estimated at 242,600 t/yr although there is considerable flexibility to change the mix of the coproducts made. Methylene chloride production has declined significantly since 1985 because of an unfavorable carcinogenicity test. A projected growth rate of 0% per year is expected. Its primary uses are for paint stripping and metal cleaning. It is regulated by many federal and state laws.
Amines, Aromatic, Methylenedianiline
Authors: Lowenkron Steven 
Published: July 2004

AbstractCommercial production of 4,4′‐methylenedianiline (4,4′‐MDA) is carried out by the acid‐catalyzed reaction of formaldehyde with aniline. All processes produce polymeric MDA (PMDA), which consists of mixtures of isomers and oligomers of MDA. More than 99% of the manufactured PMDA products are used in reactions with phosgene to produce the corresponding isocyanates for use in polyurethanes. The resultant polymeric isocyanates (PMDI) are either sold commercially or are purified to isolate 4‐4′‐methylenediphenyldiisocyanate (MDI). MDI is an important intermediate in the manufacture of spandex fibers, thermoplastic resins, and coatings, and it is used in reaction injection molding (RIM) for automotive applications. The primary use of PMDI products is in rigid foam insulation, but they are also used in semiflexible foams, foundry core binders, and particle board manufacture. Nonisocyanate uses for MDA or PMDA include epoxy curing agents, filament wound pipe, wire coatings, and military applications. MDA reacts similarly to other aromatic amines under the proper conditions. All of the toxicity data on MDA have been collected using either 4,4′‐MDA or the corresponding hydrochloride salt. Because MDA is a potentially hazardous chemical, worker exposure should be kept to a minimum. The major exposure route in workers who experience MDA poisoning is by skin contact. MDA is a suspected human carcinogen.
Microscopy
Authors: Weaver Rob 
Published: July 2004

AbstractThe microscope is arguably the most indispensable and widely used scientific instrument. There are few science or engineering disciplines that do not utilize microscopes or the data they provide to understand processes and material's properties as well as test and develop new theories. Industrial applications of the microscope continue to grow as the scale of electronic devices has passed from the micrometer to nanometer level. Microscopes are used routinely in such diverse fields as forensic science, analytical chemistry, microbiology, pathology, materials science, mineral exploration, and environmental science. It is the intent of this article to provide a concise summary of the various forms of microscopy. A great amount of discussion is devoted to the three most common types of microscopes: light microscopes; electron microscopes; and scanned probe microscopes; however, other forms of microscopy such as X‐ray, acoustic and atom probe microscopes are also discussed. For each form of microscopy there is a discussion of the principles of image formation, areas of application and strengths and weaknesses.
Genetic Engineering, Microbes
Authors: Nagarajan Vasantha , Bramucci Michael 
Published: July 2004

AbstractThe techniques involved in isolation and manipulation of genes from several microbes have become routine. Genes are cloned into plasmid or phage‐based vectors and introduced into the microbe of choice. The number of vectors that have been engineered is on the increase for several systems. In addition, construction of gene libraries and screening are also performed by small biotechnology companies. Various computational tools have become essential. The number of nucleotide and protein databases is rapidly increasing. Many software packages are available to access, manipulate, and analyze sequences. Most of the reagents needed for gene manipulation such as oligonucleotides, peptides, vectors, and antibodies are commercially available. Genetically engineered microbes are used to produce several commercial products. The number of products is likely to increase. They include therapeutics, bulk enzymes, antibiotics, chemicals, and polymer products.
Microbial Transformations
Authors: Sebek Oldrich K. , Rosazza John P. N. 
Published: July 2004

AbstractThe technology of microbial transformations is concerned with harnessing the enzymes of microorganisms to catalyze useful reactions of organic compounds. Microbial enzymes are well known for their abilities to hydrolyze, oxidize, reduce, and otherwise change the structures of organic chemicals. This review summarizes important historical applications of microbes to transform steroids, amino acids, antibiotics, sugars, and others structural classes of compounds and introduces applications of microorganisms and their enzymes as reagents in synthetic organic chemistry. It covers reactions including oxidations (hydroxylation, dioxygenation, dehydrogenation, β‐oxidation, and Baeyer‐Villiger oxidation), reductions (of ketones, double bonds, and carboxylic acids), hydrolyses (esters, amides, and nitriles), condensations (acyloin, aldolase, and carboxylation), amination and deamination, dehydration,N‐ andO‐dealkylation, decarboxylation, conjugations (N‐acetylation,O‐phosphorylation, andO‐adenylylation) and isomerization. The methodology of microbial transformations is also described. Vol. 16, pp. 611–627, 100 refs. to September 1993.
Microemulsions
Authors: Smith Duane H. 
Published: July 2004

Abstract

Microemulsions are true, thermodynamically equilibrated solutions that contain a surfactant and/or other amphiphile(s); one or more nonpolar components, such as hydrocarbons; water; and, frequently, inorganic salt(s). The surfactant(s) may be nonionic, ionic, or amphoteric; but most ionic surfactants also require a nonionic cosurfactant or amphiphile to suppress formation of liquid crystals. Microemulsions are distinct from (macro)emulsions, which are thermodynamically unstable dispersions of macroscopic droplets of one or more liquid and/or liquid crystalline phases in a continuous liquid. However, a microemulsion may be one of the phases of an emulsion. The microemulsion may appear as one of three phases, for example, a middle phase in simultaneous equilibrium with a top or upper oleic phase, and a bottom or lower aqueous phase. Because the three phases are close to a tricritical point (where all three phases simultaneously become a single phase), the interfacial tensions among the three phases are several orders of magnitude less than the tensions produced by conventional micellar solutions. Moreover, by suitable changes of temperature, salinity, or other compositional variable, the composition of the middle phase can be made to vary continuously between that of the bottom and top phases. Current or potential industrial uses of microemulsions include agrochemicals, biotechnology, catalysis, cosmetics, detergency, dyeing, enhanced oil recovery, foods, pharmaceuticals,
in situ
remediation of pollutants, separations, and synthesis of nanomaterials. Annual U.S. consumption of surfactants is about 3.4 billion kg.
Microencapsulation
Authors: Thies Curt 
Published: July 2004

AbstractThies, Curt (Washington University). This article discusses the concept of microencapsulation, many processes by which microcapsules are produced, and a number of microcapsule applications. Nomenclature and selected materials used to form microcapsules are summarized briefly. Encapsulation processes discussed include complex coacervation, polymer–polymer incompatibility, interfacial andin situpolymerization, solvent evaporation, extractive drying, submerged stationary nozzle and centrifugal nozzle, spray drying, fluidized bed, and rotational suspension separation. Microcapsule applications discussed include graphic arts such as carbonless copy paper, prolonged herbicides and insecticides, oral and injectable pharmaceuticals, live cell immobilization for biomedical and biotechnological applications, enhanced performance of food ingredients such as flavors and vitamins, and several general consumer uses such as cosmetics and adhesives.
Microwave Technology—Chemical Synthesis Applications
Authors: Varma Rajender S. 
Published: July 2004

AbstractMicrowave‐accelerated chemical syntheses in various solvents as well as under solvent‐free conditions have witnessed an explosive growth. This technology, which is still in its growth phase, has found widespread application predominantly exploiting the inexpensive unmodified household microwave (MW) ovens although the use of dedicated MW equipment has been rapidly gaining ground. Of special interest is the environmentally friendlier solventless approach that often involves exposure of neat reactants to MW irradiation or employs supported reagents on recyclable inorganic oxides or catalysts and has been adequately demonstrated in several MW‐assisted condensation, deprotection, rearrangement, cyclization, reduction, and oxidation reactions. The rapid one‐pot preparation of heterocyclic compounds fromin situgenerated reactive intermediates and the general application to multicomponent reactions, that are adaptable for building a library of compounds, have been accomplished using this MW technique. More recently, the strategy has been extended to combinatorial chemistry and the synthesis of a newer class of solvents, ionic liquids that are essentially molten salts with barely measurable vapor pressure. The salient features of these high yield protocols, namely, the selectivity, experimental ease of manipulation, and the enhanced reaction rates are discussed.
Molybdenum and Molybdenum Alloys
Authors: Stiefel Edward I. 
Published: July 2004

Abstract
Molybdenum, a key industrial element, is used both in its pure form as a refractory metal and as an alloying element in irons and steels. Most molybdenum production is in North America, although some metal comes from other areas, especially from South America and China. The largest source of molybdenum is copper mines, where the former metal is a by‐product. Molybdenum supply, ore‐processing to commercial products, and the associated environmental considerations are reviewed.
Tools, pipelines, pumps, and various gears and dies, especially those for harsh working environments such as those found in the petroleum industry, are made from molybdenum containing alloys. The molybdenum imparts strength, hardness, and corrosion resistance to steels and cast irons. Molybdenum is a refractory metal used in furnaces, electrodes, light bulbs, and x‐ray tubes. Properties and uses are described.
Water, Municipal Water Treatment
Authors: Singley J. E. 
Published: July 2004

AbstractMost surface waters contain varying amounts of suspended solids, including silt, clay, bacteria, viruses, etc. It is necessary to remove these prior to distribution to domestic or industrial customers. Sedimentation and filtration are the principal treatment processes. These are discussed in detail. Also discussed is the removal of colloidal particles by coagulation and flocculation. Lime and lime‐soda processes, and ion exchange are used to control hardness of water. Data on taste and odor control methods, as well as removal of organic compounds, iron and manganese, which impact on water quality, are given.
Nanotechnology
Authors: Vaidya Rajesh , López Gabriel , López José A. 
Published: July 2004

AbstractMolecular nanotechnology (also known as nanotechnology, molecular engineering, or molecular manufacturing) is the production of functional materials and structures in the 0.1 to 100 nm range (the nanoscale) by any of a variety of nanoscale physical and chemical methods. These methods include nanolithography, direct atomic and molecular manipulation with nanoscale probes, biotechnological selection and production of useful nanomaterials, and chemical synthesis and self‐assembly of functional molecules and aggregates. Examples of such materials and devices include molecular electronic devices (eg, molecular wires, diodes, transistors, memories), sensors, disease‐fighting agents (eg, microbicidal, anticancer), and assemblers (devices that manufacture a particular molecule or assembly of molecules) using nanoscale mechanical devices (eg, nanopumps, motors, gears). Nanoscale structures and devices may be constructed synthetically from their atomic or molecular constituents (the synthetic or “bottom‐up” approach, also referred to as nanochemistry), or may be constructed by fabrication techniques that use methods to form small structures from larger ones (the reductive or “top‐down” approach). Biological systems employ a variety of synthetic strategies and processes that make efficient use of a suite of atomic, interatomic, and intermolecular interactions to form highly ordered molecular and supramolecular units that perform myriad functions, including light harvesting, catalysis, environmental sensing, information storage and processing, locomotion, and self‐replication. Thus biological systems form important existence theorems and design criteria for the production of functional, nanoscale materials through nanotechnology. This article focuses on the current state‐of‐the‐art of methods that produce nanostructures and devices. These methods include biotechnology, nanolithography, atom manipulation by local probes, nanochemical synthesis, rational design, and supramolecular chemistry.
Naphthalene
Authors: Mason Robert T. 
Published: July 2004

Abstract
This article deals mainly with naphthalene. The hydrogenated naphthalenes, the alkylnaphthalenes (particularly methyl‐ and isopropylnaphthalenes), and acenaphthalene also are discussed. These aromatic hydrocarbons have the expected properties and undergo the usual reactions of electrophilic aromatic substitution as well as oxidation, a significant commercial reaction.Coal tar and petroleum are the sources of naphthalene in the United States. The principal use of naphthalene is for phthalic anhydride manufacture. Naphthalene is also a raw material for synthesis of pesticides, dispersants, and wetting agents.
Heat‐Exchange Technology, Network Synthesis
Authors: Hohmann Edward 
Published: July 2004

Abstract
Synthesis of heat‐exchange (energy) networks has shown large economic rewards and the most promise for future universal use.
The high cost of energy mandates carefully planned heat‐exchange networks for economically and environmentally viable plants. The process of developing a good heat‐exchange or energy network is most easily viewed as a multiple‐tier optimization problem. Minimum life‐time plant cost is the objective. The process includes minimizing capital and operating costs plus an emphasis on developing a robust design that includes the necessary flexibility and operability characteristics.
Many of the calculations necessary for heat‐exchange network design can be done by hand and need to be understood by every process engineer. Computational resources make it attractive for the average process designer to use a computer program to determine and evaluate alternative network configurations. Commercial heat‐exchange network programs are available and these programs typically take the raw stream data available to the process engineer for the plant and calculate the limiting network conditions. Heat‐exchange networks are concerned with just a portion of the total energy in a process plant. Ideally, a process plant should be examined for its total energy consumption.
Niacin, Nicotinamide, and Nicotinic Acid
Authors: Van Arnum Susan D. 
Published: July 2004

AbstractThe history of the discovery of nicotinic acid and nicotinamide is unusual in that these compounds were first synthesized and later their biological significance was elucidated. In the early part of the twentieth century, the importance of nicotinamide in the treatment of pellagra was determined. Specifically, nicotinic acid and nicotinic amide are constituents of the cofactors NAD and NADH which are required for many enzymatic reactions and the particular role of these cofactors is discussed. The key intermediate in the industrial synthesis of these compounds are alkyl pyridines. Methods of preparation of these intermediates as well as methods to functionalize the side chain are reviewed. Both biological and chemical approaches have found utility in this application. A review of analytical methodology is presented. An overview of the biological effects of these substances is presented. Despite their structural similarities, the safety and toxicity of these compounds are quite different and these consequences are highlighted.
Nickel and Nickel Alloys
Authors: Tundermann John H. , Tien John K. , Howson Timothy E. 
Published: July 2004

Abstract
World nickel reserves and nickel production and consumption are reviewed. The types of nickel ores that can be economically mined and the extraction and refining processes used to obtain commercial nickel products are described, as are the forms, characteristics, and uses of these products. The physical constants for nickel and the nominal chemistries and properties of a range of cast and wrought nickel alloys and superalloys are listed. The development paths for wrought nickel alloys are given.

Alloying copper, chromium, iron, molybdenum, and other elements with nickel produces a range of corrosion‐ and heat‐resistant materials strengthened by various means. These alloys can operate from cryogenic conditions to temperatures

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. Nickel containing oxide‐dispersion‐strengthened alloys, nickel–aluminide intermetallics, and advanced nickel‐matrix composites are presented.