bluuebunny/crossref_metadata_2025 huggingface dataset:
Hyperbilirubinemia Among African American, Glucose-6-Phosphate Dehydrogenase-Deficient Neonates
Authors: Kaplan Michael , Herschel Marguerite , Hammerman Cathy , Hoyer James D. , Stevenson David K.
Published: August 2004

Background. Although glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is prevalent in African Americans, their risk of associated neonatal hyperbilirubinemia has not been prospectively studied.

Objective. To compare hemolysis and the risk of hyperbilirubinemia among African American, G-6-PD-deficient neonates (study group) and G-6-PD-normal control subjects.

Methods. Consecutive, healthy, term and near-term, male neonates born to African American mothers comprised the patient cohort. G-6-PD testing was performed with umbilical cord blood samples. Routine management included measurement of the end tidal carbon monoxide level corrected for ambient carbon monoxide level (ETCOc) within 4 hours after delivery (assessment of hemolysis), ≥1 predischarge bilirubin determination, and additional bilirubin testing as clinically indicated. Indications for phototherapy were identical for study patients and control subjects. Neonates were monitored for the first 1 week of life. ETCOc results, the incidence of hyperbilirubinemia (defined as a transcutaneous or plasma total bilirubin concentration of ≥95th percentile for the hour of life), and the need for phototherapy were compared between the G-6-PD-deficient and G-6-PD-normal groups.

Results. Five hundred male patients were enrolled, of whom 64 (12.8%) were G-6-PD-deficient. ETCOc values (median and interquartile range) were higher among G-6-PD-deficient neonates than among control neonates (2.4 ppm [2.0–2.9 ppm] vs 2.1 ppm [1.7–2.5 ppm]). More G-6-PD-deficient neonates developed hyperbilirubinemia than did control subjects (14 of 64, 21.9%, vs 29 of 436, 6.7%; relative risk: 3.27; 95% confidence interval: 1.83-5.86), whereas 13 (20.3%) met the criteria for phototherapy, compared with 25 control subjects (5.7%) (relative risk: 3.53; 95% confidence interval: 1.91-6.56). No cases of kernicterus were observed.

Conclusions. Within the African American neonatal population, there is a subgroup of G-6-PD-deficient infants with elevated rates of hemolysis, a higher incidence of hyperbilirubinemia, and a greater requirement for phototherapy, compared with G-6-PD-normal control subjects. These newborns should be monitored vigilantly for the development of hyperbilirubinemia.
Dating Violence and Associated Sexual Risk and Pregnancy Among Adolescent Girls in the United States
Authors: Silverman Jay G. , Raj Anita , Clements Karen
Published: August 2004

Objectives. To assess the annual prevalence of physical violence from dating partners among a representative sample of sexually experienced adolescent girls attending US public and private high schools, as well as sexual risk behaviors and pregnancy among this population.

Design, Setting, Participants, and Measures. Female students (9th through 12th grade) (N = 6864) participating in the 2001 National Youth Risk Behavior Survey completed measures of physical dating violence during the previous year, as well as assessments of health risk behaviors. Annual rates of physical dating violence were estimated for sexually experienced (n = 3085) and inexperienced girls. Multiple logistic regression models were constructed to assess whether physical dating violence in the previous year was associated with sexual health risks and pregnancy, after controlling for effects of potentially confounding demographic features and risk behaviors.

Results. Slightly less than 1 of 5 sexually experienced US adolescent girls (17.7%) reported being intentionally physically hurt by a date in the previous year, and ∼1 of 25 girls (3.7%) who reported no sexual experience reported such violence. Dating violence among sexually experienced adolescent girls was related to increased risks for both sexual risk behaviors (eg, recent multiple sexual partners: odds ratio: 2.0; 95% confidence interval: 1.3–3.1) and pregnancy (odds ratio: 1.8; 95% confidence interval: 1.3–2.4).

Conclusions. Dating violence is prevalent among US adolescent girls, especially those reporting having had sexual intercourse. Adolescent girls intentionally hurt by a date in the previous year are more likely to experience sexual health risks, including those increasing vulnerability to human immunodeficiency virus infection and other sexually transmitted infections, and to have been pregnant. Dating violence should be integrated into sexual health and pregnancy prevention programs, and greater efforts to identify girls experiencing dating violence are needed among those providing care related to adolescent sexual and reproductive health.
Natural History of Lipid Abnormalities and Fat Redistribution Among Human Immunodeficiency Virus-Infected Children Receiving Long-Term, Protease Inhibitor-Containing, Highly Active Antiretroviral Therapy Regimens
Authors: Taylor Perdita , Worrell Carol , Steinberg Seth M. , Hazra Rohan , Jankelevich Shirley , Wood Lauren V. , Zwerski Sheryl , Yarchoan Robert , Zeichner Steven
Published: August 2004

Objective. To characterize the type and frequency of biochemical lipid abnormalities and physical changes in body composition associated with the use of protease inhibitor (PI)-containing antiretroviral therapy among human immunodeficiency virus-infected children treated for up to 6 years.

Methods. A retrospective study of human immunodeficiency virus-infected pediatric patients enrolled in research protocols between August 1995 and December 2001 was performed. All patients who had received a PI for ≥2 years as part of their investigational antiretroviral treatment regimens during the study period were eligible. Of the 110 patients identified as having received PI therapy, 94 met the study criteria.

Results. Of the 94 patients evaluated, 9 patients (10%) developed fat redistribution as well as dyslipidemia, 49 patients (52%) developed dyslipidemia without associated physical changes, and 36 patients (38%) exhibited no elevation of lipid levels or physical signs of fat redistribution. For all 9 patients with fat redistribution, the onset of the physical changes was closely associated with changes during pubertal development. Fat redistribution was also associated with lower viral loads and higher, more sustained levels of dyslipidemia. The onset of dyslipidemia and fat redistribution peaked between 10 and 15 years of age.

Conclusion. Among pediatric patients receiving PI therapy, there seems to be an age range in which children are at greater risk of developing hypercholesterolemia and subsequent fat redistribution, suggesting that unidentified physiologic changes associated with puberty may predispose pediatric patients treated with PI therapy to developing lipodystrophy.
Acute Myocardial Infarction in a Child: Possible Pathogenic Role of Patent Foramen Ovale Associated With Heritable Thrombophilia
Authors: Carano Nicola , Agnetti Aldo , Hagler Donald J. , Tchana Bertrand , Squarcia Umberto , Bernasconi Sergio
Published: August 2004

We report an 8-year-old girl who presented with clinical features of an acute myocardial infarction. The angiographic appearance of the coronary arteries was normal. A thrombophilic state caused by a homozygote genotype for the prothrombin G20210A mutation was detected, and a patent foramen ovale (PFO) with right-to-left shunting after Valsalva maneuver was demonstrated by transesophageal contrast echocardiography. No other embolic source was identified. We suggest that paradoxical embolization through a PFO resulted in a myocardial infarction in this young patient with hereditary thrombophilia. We closed the patient’s PFO with a 25-mm PFO occluder. She was anticoagulated with warfarin for 6 months. After 6 months, a contrast echocardiogram showed no evidence of residual atrial shunt. There has been no evident recurrent paradoxical embolization.
Neonatal Genital Herpes Simplex Virus Type 1 Infection After Jewish Ritual Circumcision: Modern Medicine and Religious Tradition
Authors: Gesundheit Benjamin , Grisaru-Soen Galia , Greenberg David , Levtzion-Korach Osnat , Malkin David , Petric Martin , Koren Gideon , Tendler Moshe D. , Ben-Zeev Bruria , Vardi Amir , Dagan Ron , Engelhard Dan
Published: August 2004

Objective. Genital neonatal herpes simplex virus type 1 (HSV-1) infection was observed in a series of neonates after traditional Jewish ritual circumcision. The objective of this study was to describe neonate genital HSV-1 infection after ritual circumcision and investigate the association between genital HSV-1 after circumcision and the practice of the traditional circumcision.

Methods. Eight neonates with genital HSV-1 infection after ritual circumcision were identified.

Results. The average interval from circumcision to clinical manifestations was 7.25 ± 2.5 days. In all cases, the traditional circumciser (the mohel) had performed the ancient custom of orally suctioning the blood after cutting the foreskin (oral metzitzah), which is currently practiced by only a minority of mohels. Six infants received intravenous acyclovir therapy. Four infants had recurrent episodes of genital HSV infection, and 1 developed HSV encephalitis with neurologic sequelae. All four mohels tested for HSV antibodies were seropositive.

Conclusion. Ritual Jewish circumcision that includes metzitzah with direct oral–genital contact carries a serious risk for transmission of HSV from mohels to neonates, which can be complicated by protracted or severe infection. Oral metzitzah after ritual circumcision may be hazardous to the neonate.
Pertussis Pneumonia, Hypoxemia, Hyperleukocytosis, and Pulmonary Hypertension: Improvement in Oxygenation After a Double Volume Exchange Transfusion
Authors: Romano Michael J. , Weber Mark D. , Weisse Martin E. , Siu Benjamin L.
Published: August 2004

A 3-month-old infant of 33 weeks' gestation was hospitalized with pneumonia caused by Bordetella pertussis. Respiratory insufficiency worsened, and on hospital day 3, there was severe pulmonary dysfunction (arterial oxygen pressure/fraction of inspired oxygen ratio: 120), extreme leukocytosis (white blood cell count 104 000/mm3), and severe pulmonary hypertension as assessed by 2-dimensional echocardiogram. A double volume exchange transfusion was performed to reduce the leukocyte mass. Oxygenation began to improve during the exchange and continued to improve over the ensuing 31 hours (arterial oxygen pressure/fraction of inspired oxygen ratio: 280). The white blood cell count fell dramatically after the exchange, and the rate of rise was slower after exchange therapy compared with preexchange.
Intrauterine Baclofen Exposure: A Multidisciplinary Approach
Authors: Moran Lisa R. , Almeida Pamela G. , Worden Susan , Huttner Kenneth M.
Published: August 2004

Maternal use of the antispasmodic baclofen during pregnancy is an uncommon clinical scenario and leads to uncertainty regarding neonatal risks. We present a team-based, peripartum management plan designed for safe monitoring and minimizing the risk of neonatal withdrawal after unusual drug exposure. Incorporating the expertise of neonatology, nursing, pharmacy, neurology, and the lactation service, as well as parental input, this consensus approach was implemented in a case of maternal oral baclofen use with a successful outcome for the infant and family.
All That Is Vesicular Is Not Herpes: Incontinentia Pigmenti Masquerading as Herpes Simplex Virus in a Newborn
Authors: Faloyin Morayo , Levitt Jacob , Bercowitz Eric , Carrasco Daniel , Tan Jianyou
Published: August 2004

Incontinentia pigmenti is a multisystem genodermatosis characterized by cutaneous, neurologic, ophthalmologic, and dental abnormalities. The skin lesions associated with the disease progress through 4 stages, the first being erythematous vesicles linearly distributed along the lines of Blaschko. We report a case of an infant who had incontinentia pigmenti and presented with 2 crops of vesicles and was initially thought to have herpes simplex virus.
Statin‐Associated Peripheral Neuropathy: Review of the Literature
Authors: Chong Pang H. , Boskovich Alexandra , Stevkovic Natasa , Bartt Russell E.
Published: August 2004

Various pharmacologic agents are available for the treatment of hypercholesterolemia, including 3‐hydroxy‐3‐methylglutaryl coenzyme A (HMG‐CoA) reductase inhibitors, commonly referred to as statins, which offer favorable lipid‐lowering effects and reductions in morbidity and mortality. Statins are usually better tolerated than other lipid‐lowering agents and therefore have become a mainstay of treatment for hypercholesterolemia. However, recent case reports of peripheral neuropathy in patients treated with statins may have gone unnoticed by health care professionals. To evaluate the possible link between statins and peripheral neuropathy, literature searches using MEDLINE (January 1993–November 2003) and International Pharmaceutical Abstracts (January 1970–June 2002) were performed. Key search terms were statin, neuropathy, and HMG‐CoA reductase inhibitors. Based on epidemiologic studies as well as case reports, a risk of peripheral neuropathy associated with statin use may exist; however, the risk appears to be minimal. On the other hand, the benefits of statins are firmly established. These findings should alert prescribers to a potential risk of peripheral neuropathy in patients receiving any of the statins; that is, statins should be considered the cause of peripheral neuropathy when other etiologies have been excluded.
Biliary Excretion of Imatinib Mesylate and Its Metabolite CGP 74588 in Humans
Authors: Ramalingam Sakkaraiappan , Lagattuta Theodore F. , Egorin Merrill J. , Hayes Michael J. , Ramanathan Ramesh K.
Published: August 2004

Imatinib mesylate, licensed to treat chronic myelogenous leukemia and gastrointestinal stromal tumors, is metabolized by cytochrome P450 3A and undergoes little renal excretion, but its biliary excretion by humans is uncharacterized. Liquid chromatography–mass spectrometry was used to quantitate imatinib and its metabolite CGP 74588 in the bile of two patients with biliary stents; the ratio of imatinib:CGP 74588 in each was approximately 9:1. In the first patient, who was receiving long‐term therapy with imatinib 400 mg/day and had normal liver function tests, biliary imatinib accounted for 17.7% of the daily dose and CGP 74588 accounted for 2.1%. In the second patient, who had elevated liver function tests and was studied after his first dose of imatinib 300 mg, biliary imatinib accounted for only 1.8% of the daily dose and CGP 74588 accounted for 0.2%. These data show both the qualitative similarities and the quantitative variability in biliary excretion of imatinib and its principal metabolite.
Abrasives
Authors: Rue Charles V.
Published: August 2004

An abrasive is a substance used to abrade, smooth, or polish an object. Usually, abrasive connotes a very hard substance, ranging up to the hardest material known, diamond. There are three basic forms of abrasives: grit (loose particles); bonded materials (particles bonded into wheels, segments, or stick shapes); and coated materials (particles bonded to paper, plastic, cloth, or metal). Properties of abrasive materials include hardness, toughness, ie, ability of an abrasive grit to withstand impact without cracking, spalling, or shattering, melting temperature, chemical reactivity, thermal conductivity, and fracture characteristics. Naturally occurring abrasives remain an important item of commerce, though synthetic abrasives, eg, diamonds, corundum, emery, garnet, silica, sandstone, tripoli, pumice, and pumicite, fill many of their former uses. Manufactured abrasives include silicon carbide, fused aluminum oxide, synthetic diamond, cubic boron nitride, and grit. Coated abrasives consist of a flexible backing which holds a coating of abrasive grains. Grinding wheels are the most important bonded abrasive product. The latter are specified by a standard marking system used throughout most of the world, allowing the user to recognize the type and size of the abrasive. Both natural and manufactured abrasive grains are used loose in such operations as polishing, buffing, and lapping.
Acrylonitrile Polymers, ABS Resins
Authors: Kulich Donald M. , Pace John E. , Fritch Leroy W. , Brisimitzakis Angelo
Published: August 2004

Acrylonitrile–butadiene–styrene (ABS) polymers are composed of elastomer dispersed as a grafted particulate phase in a thermoplastic matrix of styrene and acrylonitrile copolymer (SAN). The presence of SAN grafted onto the elastomeric component, usually polybutadiene or a butadiene copolymer, compatabilizes the rubber with the SAN component. Property advantages provided by this graft terpolymer include excellent toughness, good dimensional stability, good processibility, and chemical resistance. The system is structurally complex. This allows considerable versatility in the tailoring of properties to meet specific product requirements. Consequently, research and development in ABS systems is active. Numerous grades of ABS are available, including new alloys and specialty grades for high heat, flaming‐retardant, or static dissipative product requirements. Good chemical resistance combined with the relatively low water absorptivity\documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${{(}{\rm{<}}1{\%}{)}}$\end{document}results in high resistance to staining agents. Antioxidants substantially improve oxidative stability. Applications involving extended outdoor exposure require the use of stabilizing additives, pigments, and protective coatings. In manufacturing, grafting is achieved by the free‐radical copolymerization of styrene and acrylonitrile monomers. The three commercial processes for manufacturing ABS are emulsion, mass, and mass‐suspension. ABS is sold as an unpigmented product for on‐line coloring using color concentrates during molding, or as precolored pellets. ABS can be processed by compression and injection molding, extrusion, calendering, and blow‐molding. Post‐processing operations include cold forming, painting, and adhesive bonding. As a “bridge” polymer between commodity plastics and higher performance engineering thermoplastics, ABS has become the largest selling engineering thermoplastic.
Acetylene‐Derived Chemicals
Authors: Hort Eugene V. , Taylor Paul
Published: August 2004

Acetylene, C2H2, is an extremely reactive hydrocarbon, principally used as a chemical intermediate. Because of its relatively high price, there have been continuing successful efforts to replace acetylene with cheaper raw materials. The name ethynylation was coined by Reppe to describe the addition of acetylene to carbonyl compounds. Principal Reppe acetylene chemicals include propargyl alcohol, butynediol, butenediol, butanediol, and butyrolactone. Butynediol is principally consumed in manufacture of butenediol and butanediol. Butanediol is consumed in manufacture of butyrolactone and tetrahydrofuran. Large amounts are also used as a monomer for polyesters and polyurethanes. Butyrolactone is principally used as an intermediate for manufacture of pyrrolidones. Propargyl alcohol is a primary skin irritant and severe eye irritant, highly toxic by all means of ingestion. Catalytic vinylation, in which a labile hydrogen compound adds to acetylene, forming a double bond, has been applied to a wide range of alcohols, phenols, thiols, and carboxylic acids. Vinyl ethers are used in the manufacture of glutaraldehyde and as monomers.
Acrylic Acid and Derivatives
Authors: Bauer William
Published: August 2004

Acrylic acid (propenoic acid) is prepared using acrolein from the catalytic oxidation of propylene. Acrylates are primarily used to prepare emulsion and solution polymers. The emulsion polymerization process provides high yields of polymers in a form suitable for a variety of applications. Acrylate emulsions are used in the preparation of paints, floor polishes, and adhesives. Solution polymers of acrylates are employed in the preparation of industrial coatings. The polymeric products share qualities of high resistance to chemical and environmental attack and attractive strength properties. Acrylic acid and its esters react readily with electrophilic, free‐radical, and nucleophilic agents.
Acrylonitrile
Authors: Brazdil James F.
Published: August 2004

Acrylonitrile (also called acrylic acid nitrile, propylene nitrile, vinyl cyanide, and propenoic acid nitrile) is among the top 50 chemicals produced in the United States as a result of the tremendous growth in its use as a starting material for a wide range of chemical and polymer products. Acrylic fibers remain the largest use of acrylonitrile; other significant uses are in resins and nitrile elastomers and as an intermediate in the production of adiponitrile and acrylamide. Acrylonitrile (C3H3N,\documentclass{article}\pagestyle{empty}\begin{document}${{\rm{mol\ wt}}=53.064}$\end{document}) is an unsaturated molecule having a carbon–carbon double bond conjugated with a nitrile group. Acrylonitrile is miscible in a wide range of organic solvents, including acetone, benzene, carbon tetrachloride, diethyl ether, ethyl acetate, ethylene cyanohydrin, petroleum ether, toluene, some kerosenes, and methanol. Acrylonitrile undergoes a wide range of reactions at its two chemically active sites, the nitrile group and the carbon–carbon double bond. Acrylonitrile is transported by rail car, barge, and pipeline. Department of Transportation (DOT) regulations require labeling acrylonitrile as a flammable liquid and poison. Acrylonitrile is highly toxic if ingested. It is moderately toxic if inhaled. Acrylonitrile is categorized as a cancer hazard by OSHA. Acrylonitrile will polymerize violently in the absence of oxygen if initiated by heat, light, pressure, peroxide, or strong acids and bases. It is combustible and ignites readily, producing toxic combustion products. Federal regulations (40 CFR 261) classify acrylonitrile as a hazardous waste. Uses of acrylonitrile include acrylic fiber, acrylonitrile–butadiene–styrene (ABS) resins, elastomers, and styrene–acrylonitrile resins (SAN).
Fibers, Acrylic
Authors: Knorr Raymond S.
Published: August 2004

The first reported synthesis of acrylonitrile and polyacrylonitrile was in 1894. The first acrylic fiber was introduced in 1944 by Du Pont and by the 1950s at least 18 companies were developing acrylic fiber products. In the 1970s the growth rate decreased sharply due to the maturing of the wool replacement market and an increase in the use of nylon. Acrylics retain their traditional markets and, in addition, have small market shares in many new areas such as carbon fiber precursors, asbestos replacement fibers, and conductive/metallized fibers.

Physical properties, chemical properties, polymer analysis, fiber characterization, solution spinning, commercial products, and economic aspects are discussed.
Actinides and Transactinides
Authors: Seaborg Glenn T.
Published: August 2004

The actinide elements are a group of chemically similar elements with atomic numbers 89 through 103, and include actinium, thorium, protactinium, uranium, neptunium, plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium, and lawrencium. Each of the elements has a number of isotopes, all radioactive. Thorium, uranium, and plutonium are well known for their role as the basic fuels (or sources of fuel) for the release of nuclear energy. The importance of the remainder of the actinide group lies at present in research. The actinides present a storage‐life problem in nuclear waste disposal. Only the members of the actinide group through Pu have been found to occur in nature. Thorium and uranium occur widely in the earth's crust in combination with other elements, and, in the case of uranium, in significant concentrations in the oceans. With these exceptions, the actinide elements are synthetic in origin for practical purposes, ie, they are products of nuclear reactions. All of the actinide elements are radioactive and, except for thorium and uranium, special equipment and shielded facilities are usually necessary for their manipulation. Special techniques for experimentation with the actinide elements other than Th and U have been devised because of the potential health hazard to the experimenter and the small amounts available. The actinide elements exhibit uniformity in ionic types. Corresponding ionic types are similar in chemical behavior, although the relative stabilities differ from element to element. Of the actinide ions, the small, highly charged

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ions exhibit the greatest degree of hydrolysis and complex ion formation. The actinide metals, like the lanthanide metals, are highly electropositive. They can be prepared by the electrolysis of molten salts or by the reduction of a halide with an electropositive metal, such as calcium or barium. Thousands of compounds of the actinide elements have been prepared. The elements beyond the actinides in the periodic table can be termed the transactinides. These begin with the element having atomic number 104 and extend, in principle, indefinitely. Although only six such elements, numbers 104–109, were definitely known in 1991, there are good prospects for the discovery of a number of additional elements just beyond number 109 or in the region of larger atomic numbers. They are synthesized by the bombardment of heavy nuclides with heavy ions. Modern high speed computers have made possible the calculation of electronic structure, upon which chemical properties must be based. Elements in and near the island of stability based on element 114 can be predicted to have chemical properties as follows: element 114 should be a homologue of lead, that is, should be eka‐lead; and element 112 should be eka‐mercury, etc.
Adhesives
Authors: Pocius Alphonsus V.
Published: August 2004

Anadhesiveis a material capable of holding together solid materials by means of surface attachment.Adhesionis the physical attraction of the surface of one material for the surface of another. There is no unifying theory of adhesion describing the relationship between practical adhesion and the basic intermolecular and interatomic interactions which take place between the adhesive and the adherend. The existing adhesion theories are, for the most part, rationalizations of observed phenomena, although predictions regarding the relative ranking of practical adhesion can actually be made. These theories includediffusion theory, which assumes mutual solubility of the adherend and adhesive,electrostatic theory, surface energetics and wettability theory, andmechanical interlocking theory, in which the adhesive is applied to a surface which is microscopically rough. For good adhesion, the adhesive and the adherend should, if possible, display mutual solubility to the extent that both diffuse into one another. The three principal forces to which adhesive bonds are subjected are a shear force in which one adherend is forced past the other, peeling in which at least one of the adherends is flexible enough to be bent away from the adhesive bond, and cleavage force, which is very similar to the peeling force. A structural adhesive is a resin system, usually a thermoset, that is used to bond high strength materials. Structural adhesives are the strongest form of adhesive and are meant to hold loads permanently. A pressure‐sensitive adhesive, a material which requires no activation other than the finger pressure, exerts a strong holding force, and should be removable from a smooth surface. Hot‐melt adhesives are 100% nonvolatile thermoplastic materials that can be heated to a melt and then applied as a liquid to an adherend; an example is sealing wax. Solvent‐based adhesives are materials that are formed by solution of a high molecular weight polymer in an appropriate solvent. Phenolics, poly(vinyl acetate) adhesives, rubber cements, and hot‐melt adhesives are the leading adhesive products in terms of monetary value. These products are used primarily in the wood, paper, and packaging industries.
Controlled Release Technology, Agricultural
Authors: Goertz Harvey M.
Published: August 2004

Controlled release fertilizers (CRFs) were originally developed to exploit the benefits of agronomic safety, increase nutrient efficiency, and reduce application frequency. However, CRFs also provide a vehicle for minimizing potential nutrient losses to the environment. Heightened attention to environmental concerns has prompted increased worldwide activity in the development and commercialization of CRFs.

This article reviews 25 controlled release fertilizer technologies that are commercially available. They are categorized as either nitrogen reaction products or coated fertilizers. Nitrogen reaction products include urea‐formaldehyde reaction products, IBDU, CDU, oxamide, and melamine. The coated fertilizer section reviews coatings of sulfur, polymer, and hybrid products combining sulfur and polymer. Polymer‐coated fertilizers are categorized by commercial manufacturers. Each technology is examined for its product properties, manufacturing, distribution, and product uses.
Allyl Monomers and Polymers
Authors: Dowbenko R.
Published: August 2004

Allyl compounds comprise a large group of ethylenic compounds having unique reactivities and uses often contrasting with those of typical vinyl‐type compounds. Unlike monovinyl compounds, monoallyl compounds do not form homopolymers of high molecular weight by free‐radical or conventional ionic mechanisms. In contrast, many allyl compounds containing two or more reactive double bonds yield solid, high molecular weight polymers by initiation with suitable free‐radical catalysts. A number of polyfunctional allyl esters have achieved importance in polymerization and copolymerization, especially to obtain heat‐resistant cast sheets and thermoset moldings. Diallyl diglycol carbonate or diethylene glycol bis(allyl carbonate) (DADC) was developed to produce by bulk polymerization cast sheets, lenses, and other shapes of outstanding scratch resistance and optical and mechanical properties. Reaction of allyl alcohol in the presence of alkali with diethylene glycol bis(chloroformate) gives the DADC monomer, a colorless liquid of mild odor. The latter is low in toxicity, but can produce skin irritation. DADC is soluble in common organic solvents and in methyl methacrylate, styrene, and vinyl acetate. It is partially soluble in amyl alcohol, gasoline, and ligroin. It is insoluble in ethylene glycol, glycerol, and water. Usage of DADC polymers in impact‐resistant, lightweight eyewear lenses has grown rapidly and is now the principal application. The three isomeric diallyl phthalates are colorless liquids of mild odor, low volatility, and relatively slow polymerization in the early stages. At ca 25% conversion, the viscous liquid undergoes gelation and polymerization accelerates. Diallyl isophthalate (DAIP) polymerizes faster than DAP. Besides application as heat‐resistant molding powders for electronic and other applications, DAIP copolymers have been proposed for optical applications. The largest use of diallyl phthalate thermoset polymers is in moldings and coatings for electronic devices requiring high reliability under long‐term adverse environmental conditions. Monomers such as allyl methacrylate (AMA) and diallyl maleate (DAM) have applications as cross‐linking and branching agents selected especially for the different reactivities of their double bonds. DAM and DAF have pungent odors and are skin irritants. Allyl methacrylate (AMA) is used as cross‐linking agent with methacrylate esters in contact lenses. Triallyl cyanurate (TAC), 2,4,6‐tris(allyloxy)‐s‐triazine, and its isomer triallyl isocyanurate (TAIC) are used as cross‐linking agents with comonomers and for aftercuring preformed polymers such as olefin copolymers in electrical insulations.N,N‐Diallyldimethyl(DADM)ammonium salts are used for the preparation of polyelectrolytes. Copolymers of diallyldimethylammonium chloride with acrylamide have been used in electroconductive coatings.
Allyl Alcohol and Monoallyl Derivatives
Authors: Nagato Nobuyuki
Published: August 2004

The technology of introducing a new functional group to the double bond of allyl alcohol was developed in the mid‐1980s. Allyl alcohol is accordingly used as an intermediate compound for synthesizing raw materials such as epichlorohydrin and 1,4‐butanediol, and this development is bringing about expansion of the range of uses of allyl alcohol. Allyl alcohol is a colorless liquid having a pungent odor; its vapor may cause severe irritation and injury to eyes, nose, throat, and lungs. It is also corrosive. Allyl alcohol is freely miscible with water and miscible with many polar organic solvents and aromatic hydrocarbons. It forms an azeotropic mixture with water and a ternary azeotropic mixture with water and organic solvents. Hydroformylation of allyl alcohol is a synthetic route for producing 1,4‐butanediol, a raw material for poly(butylene terephthalate), an engineering plastic. The\documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${{\rm{C}}{\raise1pt\hbox{$\Relbar \kern-4pt{\Relbar}$}}{\rm{C}}}$\end{document}double bond of allyl alcohol undergoes epoxidation by peroxide, yielding glycidol, applied in manufacturing glycidol as an intermediate for industrial production of glycerol. There are two processes for industrial production of allyl alcohol being used industrially at present: isomerization of propylene oxide, and a new process developed by Showa Denko K.K. The monoallyl derivative allyl chloride (AC) is a transparent, mobile, and irritative liquid produced by chlorination of propylene at high temperature. It is used mostly as an intermediate compound for producing epichlorohydrin. Allyl acetate is produced mostly for manufacturing allyl alcohol. Allyl methacrylate (AMA) is used mostly as a raw material for silane coupling agents. Allyl glycidyl ether is used mainly as a raw material for silane coupling agents and epichlorohydrin rubber. Dimethylallylamine is used in the production of insecticides and pesticides. Most allyl compounds are toxic and many are irritants. Precautions should be taken at all times to ensure safe handling.
Amyl Alcohols
Authors: Papa Anthony J.
Published: August 2004

Amyl alcohol describes any saturated aliphatic alcohol containing five carbon atoms. This class consists of three pentanols, four substituted butanols, and a disubstituted propanol, ie, eight structural isomers C5H12O: four primary, three secondary, and one tertiary alcohol. In addition, 2‐pentanol, 2‐methyl‐1‐butanol, and 3‐methyl‐2‐butanol have chiral centers and hence two enantiomeric forms. The odd‐carbon structure and the extent of branching provide amyl alcohols with unique physical and solubility properties and often offer ideal properties for solvent, surfactant, extraction, gasoline additive, and fragrance applications. Today the most important industrial process for amyl alcohol production is low pressure rhodium‐catalyzed hydroformylation (oxo process) of butenes. Mixtures of isomeric amyl alcohols (1‐pentanol and 2‐methyl‐1‐butanol) are often preferred because they are less expensive to produce commercially and have a more desirable combination of properties. With the exception of neopentyl alcohol (mp 53°C), the amyl alcohols are clear, colorless liquids under atmospheric conditions, with characteristic, slightly pungent and penetrating odors. Commercial primary amyl alcohol is a mixture of 1‐pentanol and 2‐methyl‐1‐butanol. Like the lower alcohols, amyl alcohols are completely miscible with numerous organic solvents and are excellent solvents for nitrocellulose, resin lacquers, higher esters, and various natural and synthetic gums and resins. However, in contrast to the lower alcohols, they are only slightly soluble in water. Important amyl alcohol reactions include dehydration, esterification, oxidation, amination, etherification, and condensation. Three significant commercial processes for the production of amyl alcohols include separation from fusel oils, chlorination of C‐5 alkanes with subsequent hydrolysis to produce a mixture of seven of the eight isomers (Pennsalt), and a low pressure oxo process. The oxo process is the principal one in practice today. The main effects of prolonged exposure to amyl alcohols are irritation to mucous membranes and upper respiratory tract, significant depression of the central nervous system, and narcotic effects from vapor inhalation or oral absorption. All the alcohols are harmful if inhaled or swallowed. Prolonged exposure causes nausea, coughing, diarrhea, vertigo, drowsiness, headache, and vomiting. 3‐Methyl‐1‐butanol has demonstrated carcinogenic activity in animal studies. The amyl alcohols are readily flammable substances;tert‐amyl alcohol is the most flammable. Their vapors can form explosive mixtures with air. Amyl alcohols are best stored or shipped in either aluminum, lined steel, or stainless steel tanks.
Aquaculture
Authors: Stickney Rorbert
Published: August 2004

Aquaculture is the rearing of aquatic organisms under controlled or semicontrolled conditions. It involves plant and animal rearing with the objectives of providing human food, recreational fishing, enhancement of commercially valuable stocks, recovery of endangered species, and the production of bait and ornamental species. Aquaculture is conducted in ponds, raceways, cages, and net‐pens. It may also involve suspending molluscs from rafts or ropes, rearing them in baskets or trays, or placing them on the bottom in the natural environment. Technology levels range considerably with the highest level being found in conjunction with recirculating systems. Culturists attempt to control water quality, reproduction and diseases. They also employ feeds specifically designed for the animals being produced. Most species are maintained in captivity throughout the life cycle. Selective breeding is often used as a means of improving stocks of cultured organisms. Diseases can pose significant problems for aquaculturists. Avoidance of stress reduces disease incidence, but treatments, including drugs and vaccines are available for at least some aquatic animal diseases. The final task of the aquaculturist is to ensure that the product reaches the processor in the best possible condition. Careful handling during harvest helps ensure product quality.
Arsenic and Arsenic Alloys
Authors: Carapella S. C.
Published: August 2004

Arsenic, although often referred to as a metal, is classified chemically as a nonmetal or metalloid and belongs to Group 15 (VA) of the Periodic Table (as does antimony). The principal valences of arsenic are\documentclass{article}\pagestyle{empty}\begin{document}${+3}$\end{document},\documentclass{article}\pagestyle{empty}\begin{document}${+5}$\end{document}, and\documentclass{article}\pagestyle{empty}\begin{document}${-3}$\end{document}. Only one stable isotope of arsenic having mass 75 (100% natural abundance) has been observed. Metallic arsenic is stable in dry air, but when exposed to humid air the surface oxidizes, giving a superficial golden bronze tarnish that turns black upon further exposure. The amorphous form is more stable to atmospheric oxidation. Upon heating in air, both forms sublime and the vapor oxidizes to arsenic trioxide, As2O3. Elemental arsenic combines with many metals to form arsenides. Arsenic is widely distributed about the earth and has a terrestrial abundance of approximately 5 g/t. The most important commercial source of arsenic, however, is as a by‐product from the treatment of copper, lead, cobalt, and gold ores. Arsenic metal is also offered in high (ranging from 99.99% to in excess of\documentclass{article}\usepackage{amssymb}\pagestyle{empty}\begin{document}${99.999{\%}+}$\end{document}) purity form for semiconductor applications. The predominant use of arsenic in the United States is in the manufacture of chemicals. During the 1980s, the market for arsenic chemicals had shifted from cotton farming, where its use is now restricted because of environmental considerations, to wood preservatives for the protection of lumber and other wood products. Arsenic trioxide is the basic commodity of commerce from which a number of important chemicals are manufactured. Trace quantities of arsenic are added to lead–antimony grid alloys used in lead–acid batteries. Phosphorized deoxidized arsenical copper (alloy 142) is used for heat exchangers and condenser tubes. The toxicity of arsenic ranges from very low to extremely high depending on the chemical state. Metallic arsenic and arsenious sulfide, As2S3, have low toxicity. Arsine is extremely toxic. The toxicity of other organic and inorganic arsenic compounds varies. Arsenic is classified as a carcinogen by the International Agency for Research on Cancer (IARC). The handling of arsenic in the work‐place should be in compliance with the U.S. Occupational Safety and Health Administration (OSHA) regulations. Precautions should be taken to avoid accidental generation of arsine gas. Disposal of arsenical products should be in compliance with Federal and local government environmental regulations.
Graphite, Artificial
Authors: Lewis I. C.
Published: August 2004

The raw materials used in the production of manufactured carbon and graphite largely control the ultimate properties and practical applications of the final product. This dependence is related to the chemical and physical nature of the carbonization and graphitization processes. Essentially any organic material can be thermally transformed to carbon. The carbonization process through the elimination of heteroatoms and substituent hydrogen converts the organic precursor into a carbon polymer. This polymer consists of aromatic carbons arranged in large polynuclear aromatic ring systems. With continued heat treatment, this carbon is transformed to a more or less ordered three‐dimensional framework approaching the structure of graphite. Differences in the final material depend on the ease and extent of completion of these overall chemical and physical ordering processes. Filler materials include petroleum coke, coal‐tar pitch coke, natural graphite, carbon blacks and anthracite. Carbon articles are made by mixing a controlled size distribution of coke filler particles with a binder such as coal‐tar or petroleum pitch. In addition to the primary ingredients, the fillers and binders, minor amounts of other materials are added at various steps in the carbon and graphite manufacturing process. They can play an important role in determining the quality of the final product. Light extrusion oils and lubricants, are often added to the mix to improve the extrusion rates and structure of the extruded products. Chemical inhibitors are introduced to reduce the detrimental effects of sulfur in high sulfur cokes. Nearly all coke utilized in carbon manufacture is calcined. Calcination consists of heating raw coke to remove volatiles and to shrink the coke to produce a strong, dense particle.
Benzyl Chloride, Benzal Chloride, and Benzotrichloride
Authors: Lin Henry C. , Bieron Joseph F.
Published: August 2004

When toluene reacts with chlorine under experimental conditions that promote free‐radical chlorination, a mixture of benzyl chloride, benzal chloride, and benzotrichloride is obtained. The product distribution is determined in large part by the chlorine:toluene ratio. Competing reactions result in chlorination of the aromatic ring, reducing the yield of side‐chain chlorination products.

Benzyl chloride undergoes reactions typical of a reactive alkyl halide. Hydrolysis gives benzyl alcohol, reaction with ammonia yields benzylamines, and benzyl esters form by reaction with salts of carboxylic acids. Reaction with other nucleophiles yield substitution products; alkoxides give benzyl ethers and cyanide give phenylacetonitrile.

Benzal chloride is hydrolyzed to benzaldehyde and benzotrichloride to benzoic acid. Benzotrifluoride is formed by the reaction of benzotrichloride with anhydrous hydrogen fluoride. Reaction conditions have been determined for aromatic ring chlorination and nitration of benzyl chloride, benzal chloride, and benzotrichloride.

More than two‐thirds of benzyl chloride produced is used to make the plasticizer benzyl butyl phthalate. Nearly all of the benzal chloride produced is consumed in the manufacture of benzaldehyde. Benzotrichloride is used in the manufacture of benzoyl chloride and in the synthesis of the herbicide intermediatep‐chlorobenzotrifluoride.
Benzoic Acid
Authors: Opgrande Jarl L. , Dobratz C. J. , Brown Edward E. , Liang Jason C. , Conn Gregory S. , With Jan , Shelton Frederick J.
Published: August 2004

Benzoic acid, C6H5COOH, is the simplest member of the aromatic carboxylic acid family. In the United States, virtually all benzoic acid is manufactured by the continuous liquid‐phase air oxidation of toluene. Benzoic acid and its salts and esters find application in medicinals, food and industrial preservatives, cosmetics, resins, plasticizers, dyestuffs, and fibers. Benzoic acid in the free state, or in the form of simple derivatives such as salts, esters, and amides, is widely distributed in nature. In its chemical behavior benzoic acid shows few exceptional properties; the reactions of the carboxyl group are normal, and ring substitutions take place as would be predicted. The growth of demand for benzoic acid is expected to increase at a rate of between 1 and 2% per year. Glycol dibenzoate plasticizers have been growing at close to 10% annually for several years, in part due to environmental concerns with regard to phthalate plasticizers. The growth of the diet soft drink market has increased the demand for sodium and potassium benzoates. All of the benzoic acid producers in the United States employ the liquid‐phase toluene air oxidation process. The bulk of benzoic acid production capacity is consumed internally by the producers. Kalama converts over half of its production to phenol. A large portion of Velsicol's benzoic acid production is utilized in the manufacture of glycol dibenzoate plasticizer esters. Benzoic acid is available in industrial and technical grades, and in grades meeting the specifications of theUnited States Pharmacopeia, theFood Chemicals Codex, or theBritish Pharmacopeia. Benzoic acid's toxicity is rated as moderate (3 on a scale of 1–6). Healthy individuals may tolerate small doses (under 0.5 g of benzoates per day) mixed with food without ill effects. The principal safety concern in handling molten benzoic acid is its elevated temperature. Thermal burns may result from improper handling of the molten product. Benzoic acid derivatives include benzoyl chloride (C6H5COCl), benzoic anhydride ((C6H5CO)2O), benzoic acid salts, and benzoic acid esters.