bluuebunny/crossref_metadata_2025_split huggingface dataset:
Benzene
Authors: Fruscella William 
Published: July 2004

AbstractBenzene, C6H6, is a volatile, colorless, and flammable liquid aromatic hydrocarbon possessing a distinct, characteristic odor. Benzene is used as a chemical intermediate for the production of many important industrial compounds, such as styrene (polystyrene and synthetic rubber), phenol (phenolic resins), cyclohexane (nylon), aniline (dyes), alkylbenzenes (detergents), and chlorobenzenes. These intermediates, in turn, supply numerous sectors of the chemical industry producing pharmaceuticals, specialty chemicals, plastics, resins, dyes, and pesticides. Benzene has also found limited application in medicine for the treatment of certain blood disorders, such as polycythemia and malignant lymphoma, and in veterinary medicine as a disinfectant. Benzene, along with other light high octane aromatic hydrocarbons such as toluene and xylene, is used as a component of motor gasoline. Benzene is no longer used in appreciable quantity as a solvent because of the health hazards associated with it. Since the 1950s, benzene production from petroleum feedstocks has been very successful and accounts for ∼ 95% of all benzene obtained. Benzene is the simplest and most important member of the aromatic hydrocarbons. Petroleum‐derived benzene is commercially produced by reforming and separation, thermal or catalytic dealkylation of toluene, and disproportionation. Benzene is also obtained from pyrolysis gasoline formed in the steam cracking of olefins. World capacity was 40 × 106t as of Jan. 2000. Several different grades of benzene are commercially available. Benzene is classified as a flammable liquid and should be stored away from any potential source of ignition. Benzene is shipped by rail tank cars, trucks, barges, and tankers. Because of the flammability, toxicity, and volatility of benzene, transfers from one vessel to another are conducted in closed systems. Benzene should be handled only where adequate ventilation is provided; protective clothing and self‐contained respirators are recommended. Benzene is classified as a hazardous waste. Benzene emissions and effluent streams from petroleum refineries or benzene processing plants are also subject to strict federal regulations.
Biocatalysis
Authors: Pannuri Sachin , DiSanto Rocco , Kamat Sanjay 
Published: July 2004

AbstractBioorganic catalysis is emerging as a powerful tool to complement traditional catalytic reactions in organic synthesis. A wide range of reactions can be catalyzed using biocatalysts, and this article attempts to introduce the reader to the variety of reactions that have been demonstrated. Although these reactions are possible in the laboratory, the challenge is to make them economically feasible on an industrial scale. Each biotransformation process has some unique obstacles to overcome before it is translated from the laboratory to commercial scale, and some of these problems are discussed. Biocatalytic properties are amenable to dramatic modification using genetic and solvent engineering, setting them apart from traditional catalysts. Many biocatalytic processes are being run on a commercial scale and one such reaction utilizing a transaminase is presented as a case study.
Biosensors
Authors: Turner A. P. F. , Laschi Serena , Mascini Marco 
Published: July 2004

Abstract

Biosensors
are chemical sensors in which the recognition system utilizes a biochemical mechanism. The term biosensor has been variously used to a number of devices either used to monitor living system or incorporating biotic elements. The current consensus is that this term should be reserved for sensors incorporating a biological element such as an enzyme, antibody, nucleic acid, microorganism, or eukariotic cell where the biological element is in intimate contact with the transducer. The main purpose of the recognition system is to provide specificity to the biosensor, thus creating a device able to detect either a specific molecular target or a related family of compounds. The ability of biosensors to detect trace and low levels of biologically active substances is the main characteristic of these systems, and for this reason they have applications in the fields of medicine, biotechnology, food, and environmental science.
Bismuth and Bismuth Alloys
Authors: Chagnon Mark J. 
Published: July 2004

Abstract
The element bismuth, Bi, found in Group 15 (VA) of the Periodic Table, has at no. 83, at wt 208.98. Its valences are +5 and +3. Bismuth is a silvery metal having a high metallic luster and exhibiting a slightly pink tinge on a cleanly broken surface. The metal itself is brittle in nature and easily broken. Bismuth is referred to as a minor metal. Bismuth occurs in the earth's crust in a concentration of approximately 0.1 ppm on the average. The physical properties of bismuth are characterized by a low melting point, a high density, and expansion on solidification. The thermal conductivity of bismuth is lower than that of any other metal except mercury. Bismuth is mined primarily as a by‐product of the processing of ores of other metals, mostly copper and lead. The principal portion of the bismuth in copper ores follows the copper into the matte. During the conversion of the matte to blister copper most of the bismuth fumes off. The fumes are caught in the baghouse or Cottrell system. The portion of the bismuth remaining with the blister copper is separated during the electrolytic refining in the slimes. The bismuth found in the lead ore accompanies the lead through the smelting operation right up to the last refining steps. Bismuth is leached from roasted tin concentrates and other bismuth‐bearing materials by means of hydrochloric acid. There are four basic forms of bismuth that are readily available commercially: ingot, needle, pellet, and powder. The three primary categories of uses of bismuth in industry are chemical, metallurgical additive, and fusible alloy. The Chemical category can be broken down into pharmaceuticals, cosmetics, catalysts, industrial pigments, and electronics, and the metallurgical additive category into steel, aluminum, and cast‐iron additives. The fusible alloy category is divisible into more than a dozen subcategories dependent on a specific application. Because bismuth alloys with certain other metals to give low melting point alloys, bismuth is particularly well‐suited for a number of uses. No industrial poisoning from bismuth has been reported. Ingestion and inhalation of dusts and fumes should be avoided.
Bismuth Compounds
Authors: Breunig Hans Joachim 
Published: July 2004

AbstractBismuth is the fifth member of the nitrogen family of elements and like its congeners possesses five electrons in its outermost shell, (6s2)(6p3). In many compounds, the bismuth atom utilizes only the three 6pelectrons in bond formation and retains the two 6selectrons as an inert pair. Compounds are also known where bismuth is bonded to four, five, or six other atoms. Many bismuth compounds do not have simple molecular structures and exist in the solid state as polymeric chains or sheets. Inorganic compounds of bismuth include bismuthine, bismuthides, bismuth halides, bismuth oxide halides, bismuth oxides and bismuthates, higher oxides of bismuth and related compounds, sulfides and related compounds, and bismuth salts. In a manner similar to phosphorus, arsenic, and antimony, the bismuth atom can be either tri‐ or pentacovalent. Methylbismuthine, CH3BiH2, and dimethylbismuthine, (CH3)2BiH, are prepared by the lithium aluminum hydride reduction of methyldichlorobismuthine, CH3BiCl2, and dimethylchlorobismuthine, respectively. Tertiary bismuthines appear to have a number of uses in synthetic organic chemistry and for a number of other industrial purposes. Chloro‐, dichloro‐, bromo‐, and dibromobismuthines are best prepared by the reaction of a tertiary bismuthine and bismuth trichloride or tribromide. Tetraalkyl‐ and tetraaryldibismuthines can be obtained by the reaction of a sodium dialkyl‐ or diarylbismuthide and a 1,2‐dihaloethane. Dibismuthines tend to be thermally unstable. They also are very sensitive to oxidation. Organobismuth(V) compounds have found considerable use as oxidizing agents. After the tertiary bismuthines, the triarylbismuth dihalides constitute the most important class of organobismuth compounds and are by far the largest class of compounds containing pentacovalent bismuth. Very few trialkylbismuth dihalides have been prepared. In addition to use in organic synthesis and limited industrial use, triarylbismuth dihalides have been used as catalysts for the carbonation of epoxides to form cyclic carbonates. A number of bismuthonium ylides, have been prepared and their reactions studied. A number of pentaarylbismuth compounds are known. Pentaphenylbismuth, C30H25Bi, is a violet‐colored, crystalline compound that decomposes spontaneously after standing for several days in a dry nitrogen atmosphere. It has been studied as a reagent in organic synthesis where it can act either as an oxidizing or an arylating agent. Commercially available preparations of Bismuth subsalicylate (Pepto‐Bismol), a basic salt of varying composition, corresponding approximately too‐HOC6H4CO2(BiO), and De‐Nol, tripotassium dicitratobismuthate (bismuth subcitrate) are applied in the treatment of duodenal ulcers, gastritis and diarrhea.
Blood Substitutes
Authors: Winslow Robert M. 
Published: July 2004

AbstractArtificial blood is herein defined as consisting of red cell substitutes. Red cell substitutes are solutions intended for use in patients whose red cells are either not available or their use is to be avoided for other reasons. More than 100 years of research have been invested in the quest to produce a solution that can be used safely in humans.Hemoglobin can exist in either of two structural conformations, corresponding to the oxy (Rrelaxed) or deoxy (Ttense) states. The key differences between these two structures are that the constrained T state has a much lower oxygen affinity than theRstate and theTstate has a reduced tendency to dissociate into subunits that can be filtered in the kidneys. Traditional efforts to modify hemoglobin to serve as a cell‐free O2carrier have been directed at stabilization of the T conformation, which would be expected to lower O2affinity of native hemoglobin and to reduce its renal excretion. Currently, the optimal O2affinity of a cell‐free hemoglobin has recently been called into question, but there is no doubt that subunit dissociation needs to be controlled or eliminated.Differences in the reactions considered to be useful in the production of hemoglobin‐based blood substitutes are determined by the dimensions and reactivity of the cross‐linking reagents. Even small differences among structures of the reagents can yield products having very different properties. In addition, the conditions of the reaction are very important, not only in regard to the state of ligation, ie, oxygen saturation, but also in regard to the presence of agents or molecules that block or compete for certain reactive sites.Hemoglobin exists in red blood cells in a highly purified form. However, red cell membranes and plasma contain components that could potentially cause toxicity in recipients of large volumes of hemoglobin preparations. Rabiner's method for the filtration purification of hemoglobin was a significant advance over older centrifugation methods, but some hemoglobins prepared in this way have still caused unwanted reactions.In addition to human blood, bovine and recombinant hemoglobins have also been used as starting materials for products. These are not without their own problems, such as the fear of bovine spongiform encephalitis (BSE) virus in bovine blood and the extensive purification needed to isolate hemoglobin from bacterial or yeast cultures. As of this writing, one product is before the Federal Department of Agriculture (FDA) for final marketing approval, one is in prolonged clinical trials, two have failed dramatically, and at least two new and novel products are in preclinical or early clinical stages.
Boric Acid Esters
Authors: Docks Edward L. 
Published: July 2004

AbstractThe general formula for boric acid esters is B(OR)3. The lower molecular weight esters such as methyl, ethyl, and phenyl are most commonly referred to as methyl borate, ethyl borate, and phenyl borate, respectively. Some of the more common boric acid esters used in industrial applications are trimethyl borate, trimethyl borate azeotrope, triethyl borate, triethyl borate azeotrope, tri‐n‐propyl borate, triisopropyl borate, tri‐n‐butyl borate, triphenyl borate, tricresyl borate, trimethoxyboroxine, and triisopropoxyboroxine. Most reported boric acid esters are trialkoxy or triaryloxy boranes. The esters range from colorless low boiling liquids to solids that possess high melting points. Boric acid esters usually have an odor similar to the hydroxy compound from which they are derived. Alkyl boric acid esters derived from straight‐chain alcohols and aryl boric acid esters are stable to relatively high temperatures. Trialkoxyboranes from branched‐chain alcohols are much less stable, and boranes from tertiary alcohols can even decompose at 100°C. Decomposition of branched‐chain esters leads to mixtures of olefins, alcohols, and other derivatives. Methods used for the preparation of borate esters, include the esterification of boric acid or boric oxide, B2O3, and transesterification. Most methyl borate is produced by Morton International and used captively to manufacture sodium borohydride. Aryl borates produce phenols when in contact with water and are therefore subject to shipping regulations governing such materials and must carry a Corrosive Chemical label. Lower alkyl borates are flammable; methyl, ethyl, and butyl borates must be stored in approved areas. Other compounds are not hazardous. Boric acid esters are used in the production of sodium borohydride, gas fluxing, as polymer additives, in hydraulic fluids and lubricants, as biocides, and in hydrocarbon oxidation.
Boron, Elemental
Authors: Jansen Linda H. 
Published: July 2004

AbstractBoron, B, is unique in that it is the only nonmetal in Group 13 (IIIA) of the Periodic Table. Boron, at wt 10.81, at no. 5, has more similarity to carbon and silicon than to the other elements in Group 13. There are two stable boron isotopes,10B and11B, which are naturally present at 19.10–20.31% and 79.69–80.90%, respectively. There is a very low cosmic abundance of boron. Boron is the 51st most common element present in the earth's crust at a concentration of three grams per metric ton. Elemental boron has a diverse and complex chemistry, influenced by its having a high ionization energy; by its small size; and by virtue of the electronegativities of boron (2.0), carbon (2.5), and hydrogen (2.1) all being very similar, resulting in extensive and unusual covalent chemistry. Boron has an expected valence of three. There is no formation of univalent compounds. Boron has a high affinity for oxygen‐forming borates, polyborates, borosilicates, peroxoborates, etc. Boron reacts with water at temperatures >100°C to form boric acid and other boron compounds. In addition to being an amorphous powder, boron has four crystalline forms: α‐rhombohedral, β‐rhombohedral, α‐tetragonal, and β‐tetragonal. Boron is an extremely hard refractory solid having a hardness of 9.3 on Mohs' scale and a very low (1.5 × 10−6 Ω−1 cm−1room temperature electrical conductivity so that boron is classified as a metalloid or semiconductor. These values are for the α‐rhombohedral form. The high ionization energies and small size prevent boron from adopting metallic bonding to compensate for its electron deficiency and that of other hypoelectronic elements. A high purity (>99%) boron comes from the direct thermal decomposition of boron hydrides such as diborane, B2H6. The Moissan process, the reduction of boric oxide with magnesium, is the most widely used commercial process for producing boron. Elemental boron is used in very diverse industries ranging from metallurgy to electronics. Other areas of application include ceramics, propulsion, pyrotechnics, and nuclear chemistry. Boron is nontoxic. It is a nutrient essential to plant growth. Workplace hygienic practices include avoiding the breathing of boron dust.
Carboxylic Acids, Branched‐Chain Acids
Authors: Johnson Robert W. , Cantrell Robert R. 
Published: July 2004

Abstract
Branched‐chain acids contain at least one branching alkyl group, which causes different physical, and in some cases different chemical, properties than their corresponding straight‐chain isomers. For example, stearic acid has a melting point of about 69°C, whereas isostearic acid has a melting point of about 5°C.

Manufacturing procedures for most branched‐chain acids are well known. Oxo process acids are manufactured from branched‐chain olefins using hydroformylation followed by oxidation. Neo acids are prepared from selected olefins using carbon monoxide. 2‐Ethylhexanoic acid is manufactured by an aldol condensation of butyraldehyde followed by an oxidation. Isostearic acid is produced from the monomeric acids obtained in the dimerization of unsaturated C
18
fatty acids.

Cobalt and manganese salts of 2‐ethylhexanoic acid are used in the formulation of greases and lubricants. Derivatives of isostearic acid have been used as pour point depressants in two‐cycle engine oils, as textile lubricants, and in cosmetics. The hazards of handling branched‐chain acids are similar to those encountered with other aliphatic acids of the same molecular weight.
Bromine, Organic Compounds
Authors: Ioffe David , Kampf Arieh 
Published: July 2004

AbstractThe scope of the article is limited to those organic bromine compounds having industrial application. The organic bromine compounds are prepared and produced either by substitutive or additive bromination. Organic bromine compounds, in which the bromine atom is retained in the final molecular structure, and where its presence contributes to the properties of the desired products, are the largest segment in terms of consumed volumes. This segment includes mainly flame retardants, biocides, gasoline additives, halons, bromobutyl rubber, pharmaceuticals, and dyes. Brominated flame retardants are the more significant and voluminous part of all bromine derivatives. Bromine consumption in flame retardants forms half of organic bromine compounds consumption. Brominated flame retardants are divided into two general classes according to their relation to polymers ‐ additive flame retardants and reactive flame retardants. The more significant and expanding group of brominated biocides is for water treatment.Organic bromine compounds have traditionally played an important role as intermediates in the production of agrochemicals, pharmaceuticals and dyes, while new process developments that results in new applications in UV sunscreens, high performance polymers and others.
Powders, Handling, Bulk Powders
Authors: Marinelli Joseph , Carson John W. 
Published: July 2004

AbstractWhen work on the development of the theory of bulk solids flow began in the early 1950s, bulk solids were thought to behave much like liquids, and thus were expected to flow easily from bins. Powder flow is not always reliable, however. The field of bulk solids flow has since been developed to allow design of equipment and testing methods.Typical flow problems include no‐flow (arching, ratholing), erratic flow, flooding, limited discharge rate, and segregation. Flow patterns experienced by bulk solids include funnel flow, which occurs when some of the material in a bin moves toward the outlet while the rest remains stationary; mass flow, where all of a material is in motion whenever any is withdrawn; and expanded flow, which uses the best aspects of funnel flow and mass flow.Equipment design, maintenance, and special considerations including sifting, particle velocity, and entrainment are discussed.
Butadiene
Authors: Sun H. N. , Wristers J. P. 
Published: July 2004

AbstractButadiene, C4H6, exists in two isomeric forms: 1,3‐butadiene and 1,2‐butadiene. 1,3‐Butadiene is a commodity product of the petrochemical industry. Elastomers consume the bulk of 1,3‐butadiene, led by the manufacture of styrene–butadiene rubber (SBR). 1,3‐Butadiene is manufactured primarily as a coproduct of steam cracking to produce ethylene in the United States, Western Europe, and Japan. However, in certain parts of the world it is still produced from ethanol. The other isomer, 1,2‐butadiene, has no significant current commercial interests. 1,3‐Butadiene is a noncorrosive, colorless, flammable gas at room temperature and atmospheric pressure. It has a mildly aromatic odor. It is sparingly soluble in water, slightly soluble in methanol and ethanol, and soluble in organic solvents like diethyl ether, benzene, and carbon tetrachloride. The conjugated double bonds of 1,3‐butadiene allow a large number of reactions at both the 1,2‐ and 1,4‐positions. These reactions include addition, hydrogenation, oxidation, Diels–Alder, oligomerization, and polymerization reactions. Many of these reactions produce large volumes of important industrial materials. Butadiene reacts with a large number of chemicals, has an inherent tendency to dimerize and polymerize, and is toxic. Therefore, specific handling, storage, and shipping procedures must be followed. U.S. shipments of butadiene, which is classified as a flammable compressed gas, are regulated by the Department of Transportation. Short‐term exposure to high concentrations of butadiene may cause irritation to the eyes, nose, and throat. Dermatitis and frostbite may result from exposure to the liquid and the evaporating gas. In several epidemiological studies, elevation in mortality was observed for small subgroups and tumor types. Updated exposure limits are given. Butadiene is used primarly in polymers. Other uses are given.
Butyl Alcohols
Authors: Billig Ernst 
Published: July 2004

AbstractButyl alcohols encompass the four structurally isomeric 4‐carbon alcohols of empirical formula C4H10O. One of these, 2‐butanol, can exist in either the optically active R(−) or S(+) configuration or as a racemic (±) mixture. The butanols are all colorless, clear liquids at room temperature and atmospheric pressure with the exception oft‐butyl alcohol which is a low melting solid; it also has a substantially higher water miscibility than the other three alcohols. The butanols undergo the typical reactions of the simple lower chain aliphatic alcohols. The principal commercial source of 1‐butanol isn‐butyraldehyde, obtained from the Oxo reaction of propylene. The largest‐volume commercial derivatives of 1‐butanol aren‐butyl acrylate and methacrylate. These are used principally in emulsion polymers for latex paints, in textile applications and in impact modifiers for rigid poly(vinyl chloride). All four butanols are thought to have a generally low order of human toxicity. The C‐4 alcohols are preferably stored in baked phenolic‐lined steel tanks. However, plain steel tanks can also be employed. Storage under dry nitrogen is also recommended since it limits flammability hazards.