bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of fatigue crack growth algorithms to railway axles and comparison of two steel grades
Authors: Beretta S , Carboni M , Cantini S , Ghidini A
Published: February 2005

The reduction of the total life cycle cost of the whole wheelset requires an optimization of inspection intervals for axles. Such components can, in most European countries, endure more than 30 years of service life. During this time, they are subjected to frequent non-destructive testing (NDT) inspections. It is therefore important to assess the influence of design options, such as hollow versus solid axles or mild versus high strength steel, on the prospective crack propagation life of an axle. In the present paper two dedicated crack propagation algorithms (namely AFGROW and NASGRO) will be applied to the estimation of inspection intervals of railway axles by comparing the properties of two widely used steels.
Key issues in the application of unified railway axle standards
Authors: Snell J R
Published: February 2005

The introduction of Comité Européen de Normalisation (CEN) axle design methods has brought a unified approach to a topic that was formerly covered by a diversity of domestic national and industry standards within Europe. This paper highlights the major differences in their application from the industry standards formerly used in the United Kingdom.
A brief historical overview of the fatigue of railway axles
Authors: Smith R A , Hillmansen S
Published: February 2005

The history of railway axle design against fatigue is reviewed through a discussion of several notable accidents caused by broken axles. The earliest accidents prompted research into fatigue which resulted in a phenomenological understanding. In the last 50 years, largely through research directed towards the aircraft industry, fatigue has been recognized to be a process involving crack initiation and propagation. Fracture mechanics is now used to assist in the timing of crack inspection intervals, but a small number of failures still occur. The paper concludes with a short discussion of modern design methods, which have their origin in the nineteenth century. Some current pressures, particularly the need to reduce unsprung mass at high speeds, continue to challenge axle designers.
Labordiagnose der Schistosomiasis (Bilharziose). Laboratory diagnosis of schistosome infections
Authors: Kapaun Annette
Published: February 2005

Zusammenfassung Für die Diagnose der Schistosomiasis (Bilharziose) bei Reisenden und Patienten aus Endemiegebieten stehen neben dem direkten Parasitennachweis (S. haematobium-Eier im Urin; S. japonicum-Eier und S. mansoni-Eier im Stuhl) immundiagnostische Methoden mit hoher Sensitivität und Spezifität zur Verfügung. Der Einsatz immundiagnostischer Verfahren ist für die Erkennung schwacher Infektionen bei Reisenden gut geeignet, auf den zusätzlich durchgeführten direkten Parasitennachweis darf jedoch nicht verzichtet werden. Für dieIndikationsstellung und Befundinterpretation der Laboruntersuchung sind fundierte Kenntnisse der Krankheit und ihres Verbreitungsgebietes sowie Angaben zur Reiseanamnese, zum Expositionsrisiko und (falls vorhanden) zur klinischen Symptomatik des Patienten unerlässlich.
Newborn screening for inborn errors of metabolism with tandem mass spectrometry in Bavaria, Germany. Neugeborenen-Screening auf angeborene Stoffwechselerkrankungen mit Tandem-Massenspektrometrie in Bayern (Deutschland)
Authors: Roscher Adelbert A. , Olgemöller Bernhard
Published: February 2005

Abstract Tandem mass spectrometry (MS/MS) is rapidly being adopted by newborn screening programs to screen dried blood spots for >20 markers of disease in a single assay. We report here key developments in the introduction and validation of MS-MS screening during a >4 year of experience in Bavaria, Germany. We identified confirmed cases of treatable inborn errors of metabolism at a cumulative rate of 1:2700 (out of 525,000 newborns). This rate is considerably higher than previously recognized by combined data from traditional newborn screening and high-risk clinical screening of symptomatic patients in the same area. The application of MS-MS also made a major impact on the early detection of disease classes such as the fatty acid oxidation defects, that are associated with high mortality if left unrecognized. The overall highly favorable outcome of our model program was instrumental to advise this technique as standard care methodology in Germany.
Cs6[Fe2O6] and Rb4[Fe2O5]: New oxoferrates(III) with edge sharing FeO4 tetrahedra
Authors: Frisch Gero , Röhr Caroline
Published: February 2005

The two new oxoferrates(III) Cs6[Fe2O6] and Rb4[Fe2O5] were synthesized at temperatures of 500 and 600 °C via reaction of Fe2O3 with the elemental alkali metals (A) and their hyperoxides AO2 in the form of dark-red crystals. Their crystal structures have both been determined by single crystal X-ray diffraction. The structure of Cs6[Fe2O6] (monoclinic, P21/c, a = 724.6(2), b = 1212.1(5), c = 767.6(3) pm, β = 105.03(4)°, Z = 2, R1 = 0.0272, K6[Mn2O6] structure type) contains isolated bi nuclear anions [O2FeO2FeO2]6- composed of two edge sharing FeO4 tetrahedra, which are also known from the potassium and rubidium compounds A6[Fe2O6] that crystallize in the klassengleiche super group C2/m. Comparable building blocks are connected via common O vertices to form chains 1
∞[O1/2OFeO2FeOO1/2]4– in the rubidium ferrate(III) Rb4[Fe2O5] (monoclinic, C2/c, a = 711.43(14), b = 1750.0(5), c = 725.3(2) pm, β = 104.72(2)°, Z = 4, R1 = 0.0611). As a consequence of the edge sharing of FeO4 tetrahedra, both compounds show short Fe—Fe distances of 273.3(2) pm in Cs6[Fe2O6] and 265.6(3) pm in Rb4[Fe2O5] respectively. Based on similarities in the packing of the (FeIII/AI) cations, a structural relationship between the two compounds can be derived. The influence of the different counterions on the structure of the oxoferrate units in the phases of general composition A6[Fe2O6] and A4[Fe2O5] is discussed.
The Lewis acid-base adducts of bismuth and aluminium trihalides — crystal structures of [Bi2X4][AlX4]2(X = Cl, Br)
Authors: Beck Johannes , Hengstmann Michael , Schlüter Stefan
Published: February 2005

The reactions of BiCl3with AlCl3and of BiBr3with AlBr3yield [Bi2Cl4][AlCl4]21and [Bi2Br4][AlBr4]22in almost quantitative yield. The reactions were performed in closed, evacuated glass ampoules at temperatures of 240 °C and 200 °C, respectively. The colorless and yellow crystals are sensitive towards hydrolysis by moist air.1crystallizes in the monocline space groupP21/c(a= 7.7322(2) Å,b= 11.9565(3) Å,c= 10.3535(3) Å,β= 95.090(2)°,Z= 2),2crystallizes in the triclinic space groupP-1 (a= 7.693(2) Å,b= 7.706(2) Å,c= 9.739(2) Å,α= 104.19(2)°,β= 102.65(2)°,γ= 99.46(2)°,Z= 1). Both structures are made up of [Bi2X4] cations and [AlX4]–anions. The centrosymmetric cations consist of four membered Bi2X2rings with an additional halogen atom attached to each Bi atom in atransarrangement. The tetrahalogeno aluminate ions are almost regular tetrahedral. Although both compounds contain isomorphous ions, the structures of1and2are not isotypic. The different packing can be understood by abstracting both structures to simple AB2types.1adopts the PtHg2structure type with eightfold coordination of the cations whereas2adopts the MoSi2structure with tenfold coordination.
The 1-N amides 1
∞[Eu2(Pyr)4(PyrH)2(NH3)] · PyrH and [Yb2(Cbz)4(NH2)2(NH3)4] · 3CbzH: Distinctions in the crystal structures, thermal properties and ammonolysis tendency
Authors: Müller-Buschbaum Klaus , Quitmann Caterina C.
Published: February 2005

The low-temperature oxidation of the rare earth metals europium and ytterbium with the 1-N amines pyrrole and carbazole in liquid ammonia gave the pyrrolate 1
∞[Eu2(Pyr)4(PyrH)2(NH3)] · PyrH (1) (Pyr
– = C4H4N–, pyrrolate anion; PyrH = C4H4NH, pyrrole) and the carbazolate [Yb2(Cbz)4(NH2)2(NH3)4] · 3CbzH (2) (Cbz
– = C12H8N–, carbazolate; CbzH = C12H8NH), respectively. Though both compounds are ammine complexes, the course through the redox potentials ELn(II/III) as well as the growing steric demand of the ligand result in various differences in the properties of the products. 1 shows a 1-dimensional structure of pyrrolate, pyrrole groups and one equivalent of ammonia coordinating and bridging divalent europium centers. This includes η
5 – π-interactions between the metal centers and pyrrolate and pyrrole rings. The resulting polymer shows a rather high thermal stability and melts at 445 °C prior to decomposition under release of ammonia at 475 °C. Contrary to this, 2 contains dimeric units around trivalent ytterbium consisting of carbazolate, ammonia and NH–
2 amide groups. No π-interactions are observed. Instead ammonolysis of liquid ammonia results in formation of an amide that contains two different amide groups. The thermal stability of 2 is lower than of 1. The building units of complex 2 decompose at 310 °C without melting. Both compounds were investigated by low-temperature single crystal X-ray analysis, Mid IR, Far IR and Raman spectroscopy as well as simultaneous DTA/TG.
Tetranuclear [Zr4(OH)8(H2O)16] units in the crystal structure of ZrOI2 · 8 H2O
Authors: Sinram Diethard , Krebs Bernt
Published: February 2005

ZrOI2 · 8 H2O was synthesized from ZrI4 and concentrated aqueous HI leading to colourless crystals. Single X-ray diffraction data gave a monoclinic cell with a = 8.392(5) Å, b = 37.497(5) Å, c = 16.217(5) Å and β = 102.76(6) Å in P21/c. The zirconyl cation is tetrameric, the iodide anions exhibit no contacts to the zirconium atoms but are linked to the tetrameric cations by weak hydrogen bridge bonds.
Single crystal structure refinement of tetramethylammonium-hectorite
Authors: Seidl Wolfgang , Breu Josef
Published: February 2005

A synthetic Cs-fluorohectorite was intercalated with Tetramethylammonium-cations (TMA+). Under appropriate reaction conditions, a complete cation exchange is feasible while preserving the phase relationship between adjacent silicate layers. Starting from a three-dimensionally (3D) ordered [1] and homogeneously charged [2], synthetic Cs-hectorite it is possible to synthesize single crystals of a 3D ordered intercalation compound (TMA-hectorite). Single crystal structure refinement (TMA0.5
interMg2.5Li0.5
octSi4
tetO10F2, monoclinic, C2/m, a = 5.2735(11) Å, b = 9.1165(14) Å, c = 13.5609(35) Å, β = 97.693(3)°, V = 646.1(2) Å3, Z = 2) conclusively reveals the arrangement of the TMA-cations in the interlayer space. The results are compared with an earlier structure refinement of an analogous TMA-intercalated natural vermiculite [3] and the results of a computer simulation carried out on TMA-vermiculite [4].
Crystal structures of Gd2(Cl3CCOO)6(bipy)2(H2O)2 · 4 bipy, Pr(Cl3CCOO)3(bipy)2, Nd(Cl3CCOO)3(bipy)2 and Er(Cl3CCOO)3(bipy)2(H2O)
Authors: Rohde Alexander , John Daniela , Urland Werner
Published: February 2005

Single crystals of Gd2(Cl3CCOO)6(bipy)2 × (H2O)2 · 4 bipy, Pr(Cl3CCOO)3(bipy)2, Nd(Cl3CCOO)3 × (bipy)2 and Er(Cl3CCOO)3(bipy)2(H2O) have been obtained by reaction of the corresponding trichloroacetate salts with 2,2′-bipyridyl (bipy) in a water/ethanol (1:1) solution. Gd2(Cl3CCOO)6(bipy)2(H2O)2 · 4 bipy crystallizes in the monoclinic space group P21/c (no. 14, Z = 4, a = 1642.40(9) pm, b = 1227.36(10) pm, c = 2303.48(14) pm, β = 107.043(7)°). The Gd3+ ions are bridged to dimers by carboxylate groups and are surrounded by six oxygen and two nitrogen atoms. One 2,2′-bipyridyl molecule is coordinated to Gd3+, the two other ones are non-coordinated.

The monomeric compounds Ln(Cl3CCOO)3(bipy)2 (Ln = Pr, Nd) are isotypic with each other and crystallize in the triclinic space group P-1 (no. 2, Z = 2, Pr: a = 989.83(8) pm, b = 1032.22(8) pm, c = 1791.56(13) pm, α = 99.312(9)°, β = 102.036(9)°, γ = 99.166(9)°; Nd: a = 990.09(7) pm, b = 1030.74(8) pm, c = 1788.70(13) pm, α = 99.393(9)°, β = 102.064(8)°, γ = 99.242(9)°). The Ln3+ atom is surrounded by six oxygen and four nitrogen atoms. A chelating coordination by the carboxylate groups is observed. There are two 2,2′-bipyridyl molecules coordinated to Ln3+.

The compound Er(Cl3CCOO)3(bipy)2(H2O) crystallizes in the triclinic space group P-1 (no. 2, Z = 2, a = 1060.65(9) pm, b = 1273.35(11) pm, c = 1402.49(11) pm, α = 105.484(10)°, β = 104.504(9)°, γ = 93.712(10)°). The Er3+ ion is coordinated by four oxygen and four nitrogen atoms. There are two 2,2′-bipyridyl molecules attached to Er3+.
Neutron powder diffraction study on Li1.8Na0.2MgCl4
Authors: Nagel René , Lutz Heinz Dieter
Published: February 2005

The crystal structure of inverse spinel-type (space group Fd-3m, Z = 8), quaternary lithium chloride Li1.8Na0.2MgCl4 has been determined by neutron powder diffraction methods (a = 1044.16(7) pm, 114 reflections, R
exp = 5.23%). The sodium ions are solely placed at the octahedral 16d site together with the Mg and a part of the Li+ ions. These results are in agreement with analogous studies on the manganese compound (Lutz et al., 1989) but being in contradiction with the results of 6Li and 7Li MAS NMR experiments (Nagel et al., 2002). The reason of this discrepancy is discussed.
Surface dynamics of III—V semiconductors studied by in situ X-ray diffraction during molecular beam epitaxy
Authors: Braun Wolfgang , Kaganer Vladimir M. , Jenichen Bernd , Tinkham Brad , Ploog Klaus H.
Published: February 2005

We study the coarsening of two-dimensional crystalline islands on the (001) face of GaAs, InAs and GaSb after deposition at typical growth conditions in molecular beam epitaxy. The time-resolved island/pit size distributions are measured in situ using synchrotron X-ray diffraction and are analyzed together with the diffraction intensity oscillations during deposition. Whereas the deposition kinetics is similar for the three materials, they strongly differ in the coarsening. During coarsening, the mean correlation length grows proportional to t
n. GaAs shows coarsening exponents around n = 1 and an exponential island size distribution, in clear contrast to the behavior of InAs and GaSb, where we find coarsening closer to the expected Ostwald ripening behavior (n between 1/3 and 1/2) on InAs and extremely slow kinetics on GaSb.
The real structure of Na3BiO4 by electron microscopy, HR-XRD and PDF analysis
Authors: Vensky Sascha , Kienle Lorenz , Dinnebier Robert E. , Masadeh Ahmad S. , Billinge Simon J. L. , Jansen Martin
Published: February 2005

The real stucture of a new crystalline high temperature phase, metastable at room temperature, in the system sodium – bismuth – oxygen, β-Na3BiO4, was determinated using high resolution X-ray powder diffraction, pair distribution function analysis, and high resolution transmission electron microscopy. β-Na3BiO4 was synthesized by anodic oxidation of bismuth(III)-oxide in a sodium hydroxide – lithium hydroxide melt. The average crystal structure of β-Na3BiO4 at ambient conditions (R3m, a = 3.32141(9) Å, c = 16.4852(5) Å) is structurally related to α-NaFeO2 with metal layers almost statistically occupied in a Na:Bi ratio of 3:1. Analysis of the long-range order on the bulk material by Rietveld refinement led to approximately Na:Bi ratios of 2:1 and 4:1, in consecutive metal layers, while a detailed analysis of the local order by means of the pair distribution function revealed the existence of almost pure sodium layers and mixed 1:1 – sodium:bismuth layers. Complementary studies on single crystallites using high resolution transmission electron miscroscopy exhibited a complex domain structure with short-range ordered, partially ordered, and long-range ordered domains.
A structural differentiation of quaternary copper argyrodites: Structure — property relations of high temperature ion conductors
Authors: Nilges Tom , Pfitzner Arno
Published: February 2005

The crystal structures of 12 argyrodite type copper compounds with the general formula Cu(12–)B+nQ2–6–yX–y(B= P, As, Si, Ge;Q= S, Se;X= Cl, Br, I) were refined. The positions of the copper atoms were refined by using a non-harmonic approach. All polymorphic argyrodites were investigated in their cubic high temperature modification crystallizing in spacegroupF-43m(No. 216). A comprehensible way to describe the complex structures was developed based on a topological description of the rigid anion- andB-cation substructure as an arrangement of Frank-Kasper polyhedra. An analysis of the joint probability density function and of the one particle potentials for the copper atoms was performed to get a detailed insight in the copper distribution in these argyrodites. They can be divided into four types based on their different distribution of copper.

This classification corresponds to the physical properties of the argyrodites, especially to their ionic conductivities, which show a significant dependence on the composition.
Structural study of β-Ni(OH)2 and α-Ni(OH)2 variants for electrode applications
Authors: Dittrich Herbert , Axmann Peter , Wohlfahrt-Mehrens Margret , Garche Jürgen , Albrecht Sven , Meese-Marktscheffel Julia , Olbrich Armin , Gille Gerhard
Published: February 2005

Powder samples of β-Ni(OH)2 and doped variants of the α-Ni(OH)2 structure type were prepared by a coprecipitation method. Chemical composition was analysed by ICP. Samples were measured by X-ray powder diffraction (XRD). Single peak profiles were analysed by fitting a splitted Pearson VII funktion to the measured patterns. Peak profile data were collected and a strong anisotropic peak broadening was observed. Structure models of possible stacking orders in β-Ni(OH)2 and doped α-Ni(OH)2 were developed. DIFFaX simulations of structure models with statistical stacking orders were carried out. The simulated peak profiles were compared to the measured ones and a fairly good agreement was found. A semiquantitative analysis of the stacking faults in these materials is shown.
Cast with Style: Nineteenth-Century Cast-Iron Stoves
Authors: groft tammis kane
Published: February 2005

Cast With Style: Nineteenth-Century Cast-Iron Stoves

During the nineteenth century Albany and Troy, New York manufacturers were considered to be among the largest producers of cast-iron stoves in the world. Stoves made in these two upstate New York cities were renowned for their fine-quality castings and innovations in technology and design. The strategic location of Albany and Troy, located nine miles apart on opposite banks of the Hudson River, afforded easy and inexpensive transportation of raw materials to the foundries, and finished stoves to worldwide markets.

Cast-iron stove making reached its highest artistic achievement and technological advancements between 1840 and 1870. Flask casting and the advent of the cupola furnace permitted more elaborate designs and finer-quality castings. Stove designers borrowed freely from architectural and cabinet-makers design books, a process that resulted in the use of Greek, Roman, Egyptian and Rococo revival motifs; patriotic symbols, and lavish floral designs, all reflecting current taste and sentiment Stove types produced included Franklin, box, dumb, base-burner, parlor, cook stoves and ranges and parlor cook stoves. However, the stoves that attracted the most attention and helped to secure the reputation of Albany and Troy, as innovators in technological and decorative designs were the column parlor stoves produced during the 1830s and 1840s. These stoves were a focal point for a Victorian parlor because the overall designs incorporated current tastes in architecture, furniture and other decorative arts.

The decline of the stove industry in Albany and Troy began slowly after the Civil War, when companies went back into full production and glutted the market. Also, new deposits of iron ore were discovered in the Great Lakes region, and entrepreneurs were quick to see the potential of large western markets and began building foundries in Chicago and Detroit. As the century closed, the demands for iron were shifting toward steel.
The Prose (and Cons) of Vodka
Authors: stakhov dmitrii
Published: February 2005

The Prose (and Cons) of Vodka

Drawing extensively on his own first-hand experience as someone who came of age during the prolonged “stagnation” of the Brezhnev years, and then witnessed the upheavals of perestroika and the breakup of the Soviet Union under Gorbachev and the wild-West capitalism of the 1990s under Yeltsin, the writer and journalist Dmitrii Stakhov explores the changing fortunes of vodka, Russia’s “alcoholic drink No. 1,” and its enduring significance as a symbol, “cultural yardstick,” and economic unit of exchange over the last quarter of a century in this hard-drinking and hard-pressed nation. Stakhov’s essay details Russians’ long love affair with vodka, as well their sometimes dangerous dalliances with various vodka substitutes (often of unknown or highly dubious origin) and their more recent infatuation, in a new era of seemingly unlimited consumer choice, with other, more manifestly “Western” alcoholic drinks (whiskey, beer, wine). Stakhov suggests that the recent shifts in drinking habits in Russia (with Russians developing more discriminating and highbrow tastes) has in certain important ways entailed a loss of cultural values and a diminished sense of community and camaraderie. No one looks after the local drunk any more, and no one is interested any longer in going in on the proverbial “threesome” of Soviet times (a bottle of vodka split three ways): now it is a Darwinian world of “every man for himself.” For better or worse the old poetry and mythos of vodka, Stakhov concludes, has died, replaced instead by the harsher (and less interesting) prose of the free market.
Man Eats Dogs: The Hot Dog Stands of Chicago
Authors: kraig bruce
Published: February 2005

Man Eats Dog

Sometimes a hot dog is more than just a fast food, and the stands from which they are served in Chicago are more than simply corporate feeding places. Created by European immigrants in the Nineteenth Century and elaborated by succeeding generations, the subject of many jokes including the name itself, the hot dog represents a social and cultural history of America. Nowhere are these themes better seen than in Chicago’s hot dog stands and in the wonderful vernacular art decorating them. Stands define urban, ethnic neighborhoods, a mosaic of small communities that together compose the portrait of the city. These small places are the realms of small entrepreneurs who live seemingly untouched by the culture of modern corporate business. The art upon them embody these older, homier themes—retreat into memory, abundance, the imagined world of carnevale, and many others. To Chicagoans, hot dog stands, local eateries in general, reify the life of their hometown.
Fats and Fatty Oils
Authors: Hasenhuettl G. L.
Published: February 2005

Mankind has used fats and oils for thousands of years. However, their chemistry only began to be explained in the nineteenth century. They are composed mainly of triacylglycerols, which are esters of glycerol and linear long chain carboxylic acids. Chain length of the acids can vary from 4 to 12 carbon atoms. Fatty acids in oils contain one or more cis (Z) double bonds, while those in fats are more highly saturated. Melting properties of fats are complex due to packing of alkyl chains in polymorphic forms. Compositions of fats and oils depend on their origin. They may be derived from animals, fish, vegetables, seeds, or microorganisms.

Crude fats and oils may be isolated by hydraulic pressing, rendering, or solvent extraction. Removal of gums, waxes, pigments, volatile solvents, odors, and free fatty acids is accomplished by further processing that is essential for most applications. Product quality may be measured by fatty acid composition, melting point, iodine, acid and peroxide values, color and clarity, or functionality tests.

Fats, oils, fatty acids, and their derivatives are used in a variety of applications, such as foods, soaps, detergents, paints and varnishes, lubricants, and biodiesel fuels. In some applications they compete with petroleum derivatives.
Iron
Authors: Lepinski J. A. , Myers Jeffrey C. , Geiger Gordon H.
Published: February 2005

Iron, the fourth most abundant element in the earth's crust, is the world's least expensive, most useful metal. Iron is alloyed with other elements for commercial applications. Iron‐bearing minerals of economic importance are hematite, magnetite, goethite, siderite, ilmenite, and pyrite. These ores can be beneficiated through crushing, grinding, magnetic separation, flotation, electrostatic separation, roasting, sintering, or pelletizing. Iron oxides in the form of pellet, lump, and/or sinter are fed along with coke and limestone into the blast furnace wherein the iron oxide is reduced and melted into hot metal (pig iron); the pig iron is further refined in an oxygen converter to make steel. New technologies are being developed as alternatives to the blast furnace for reducing iron oxide. These include direct reduction and direct smelting processes. Direct reduction is the process of converting iron ore into metallic iron without melting. Direct reduced iron (DRI) is used as a high quality feed material in electric arc furnace steelmaking, oxygen steelmaking, ladle metallurgy, blast furnace ironmaking, and foundries. Normally 90 to 95% of the iron in DRI is in the metallic form. The reduction of iron oxide proceeds from hematite to magnetite to wustite to iron. The most common reductants are reformed natural gas and coal. The main commercially proven direct reduction processes are discussed. Hot briquetted iron (HBI), a densified form of DRI, is more resistant to reoxidation and corrosion. In the foundry, ferrous scrap can be melted along with coke in a cupola or induction furnace to make cast iron. Cast iron can be classified into gray, white, malleable, or ductile iron. Economic, health and safety, and environmental issues are discussed.
Manganese and Manganese Alloys
Authors: Matricardi Louis R. , Downing James ,   Updated by Staff
Published: February 2005

Manganese minerals, pretreatment of manganese ores, and smelting processes are reviewed. The reduction of manganese ores and the production of high carbon ferromanganese and of silicomanganese are discussed as is the electrolytic production of manganese metal. The safety of ferromanganese production in electric furnaces is presented.

Manganese and manganese alloy production is closely tied to the steel industry. Many specialty steels contain significant quantities of manganese. Other important uses of manganese occur in the cast iron and aluminum industries where manganese metal is used as an alloy addition to aluminum that is used for beverage containers.
Methanol
Authors: English Alan , Rovner Jerry , Brown John , Davies Simon ,   Updated by Staff
Published: February 2005

The physical and chemical properties of methanol (methyl alcohol), CH
3
OH, are summarized. The evolution of the current low pressure technology based on synthesis gas is presented. The mechanism and functionality of the methanol synthesis catalyst are discussed. Synthesis gas generation processes and feedstocks are described in detail, as are various methanol reactor configurations. The status of current research for future methanol processes, including direct oxidation routes, is summarized. Health and safety aspects of methanol storage and handling are discussed. Economic data and end‐use products are detailed.
Nucleic Acids
Authors: Rehmann Jill
Published: February 2005

Nucleic acids are essential components of all organisms. Deoxyribonucleic acids (DNA), most commonly double helical, encode the genetic information contained in living cells. Ribonucleic acids (RNA), a more diverse class of biopolymers able to adopt helical and other more complex tertiary structures, carry out a variety of intracellular functions, including transmitting the genetic message to the site of protein synthesis. Both DNA and RNA interact with a host of other molecules, eg, proteins, drugs, as well as other nucleic acids and nucleic acid constituents. The specificity of these interactions may be related to local sequence‐dependent structural variation. The structural characteristics of nucleic acids and their constituents are discussed.

Development of techniques to synthesize oligonucleotides, which are short, well‐defined sequences of DNA or RNA, provides an opportunity to study nucleic acid structure in detail. In addition, oligonucleotides have proved invaluable in analytical procedures. The unique ability of nucleic acids to bind to self‐complementary sequences has been exploited in the design of oligonucleotide probes and in antisense drug strategies. Methods for synthesizing Oligonucleotides, including both unmodified and modified analogs are discussed.
Wool
Authors: Christoe John R. , Denning Ron J. , Evans David J. , Huson Mickey G. , Jones Leslie N. , Lamb Peter R. , Millington Keith R. , Phillips David G. , Pierlot Anthony P. , Rippon John A. , Russell Ian M.
Published: February 2005

Wool, the fibrous coating from sheep, is the most important animal fiber used by the textile industry. It has been used continuously for several thousand years, the earliest type of fabric made from wool probably being a felt. Although the relative importance of wool as a textile fiber has declined with the increasing use of synthetic fibers, it remains important in some sectors of the market. This article discusses raw wool specification, fiber growth, its complex morphological and chemical structure, and the physical properties that make wool unique among textile fibers. Also discussed are the processing steps used to transform raw wool into consumer products, namely, scouring, carbonizing, carding, spinning, setting, dyeing, bleaching, printing, and treatments to reduce felting shrinkage, insect damage, and flammability. A new textile fiber made from wool (Optim, CSIRO) is also described.
African ancestry of the population of Buenos Aires
Authors: Fejerman Laura , Carnese Francisco R. , Goicoechea Alicia S. , Avena Sergio A. , Dejean Cristina B. , Ward Ryk H.
Published: February 2005

The population of Argentina today does not have a “visible” black African component. However, censuses conducted during most of the 19th century registered up to 30% of individuals of African origin living in Buenos Aires city. What has happened to this African influence? Have all individuals of African origin died, as lay people believe? Or is it possible that admixture with the European immigrants made the African influence “invisible?” We investigated the African contribution to the genetic pool of the population of Buenos Aires, Argentina, typing 12 unlinked autosomal DNA markers in a sample of 90 individuals. The results of this analysis suggest that 2.2% (SEM = 0.9%) of the genetic ancestry of the Buenos Aires population is derived from Africa. Our analysis of individual admixture shows that those alleles that have a high frequency in populations of African origin tend to concentrate among 8 individuals in our sample. Therefore, although the admixture estimate is relatively low, the actual proportion of individuals with at least some African influence is approximately 10%. The evidence we are presenting of African ancestry is consistent with the known historical events that led to the drastic reduction of the Afro‐Argentine population during the second half of the 19th century. However, as our results suggest, this reduction did not mean a total disappearance of African genes from the genetic pool of the Buenos Aires population. Am J Phys Anthropol 128:164‐170, 2005. © 2005 Wiley‐Liss, Inc.
Research trends in human osteology: A content analysis of papers published in the American Journal of Physical Anthropology
Authors: Stojanowski Christopher M. , Buikstra Jane E.
Published: February 2005

This paper explores recent research trends in human osteology, based on articles published in the American Journal of Physical Anthropology (AJPA) during two 5‐year intervals: 1980–1984 and 1996–2000. Topical “visibility” is measured in terms of article counts; “impact” is estimated through citation indices. Our results indicate that human osteologists continue to publish a range of methodological, analytical, and descriptive research papers that address a broad array of subjects. Analytical articles are cited more frequently than descriptive articles and thus have higher impact, reflecting the discipline's continued commitment to problem‐oriented research. Differences in publication patterns exist between scholars during early and later stages of their careers. Articles published by students and Ph.D.s within 2 years of their doctoral degree are more frequently descriptive than analytical, when compared to people with longer career histories. Topics such as pathology, forensic anthropology, and biodistance modeling remain highly visible, while articles on the dentition have waned. An increase in functional research directed toward the postcranial skeleton is also reflected in our data. While continued visibility for morphological investigations is apparent, the impact of recently developed applications in bone chemistry and molecular anthropology is amply documented in our data, particularly during the more recent survey years. Am J Phys Anthropol 128:98‐109, 2005. © 2005 Wiley‐Liss, Inc.
Titelbild: The First μ6‐Peroxide Transition‐Metal Complex: [Ni8(L)12(O2)]2+ (Angew. Chem. 9/2005)
Authors: Brown Emma J. , Duhme‐Klair Anne‐K. , Elliott Matthew I. , Thomas‐Oates Jane E. , Timmins Phillipa L. , Walton Paul H.
Published: February 2005

Peroxid eingefroren in perfekter Symmetrie, die beim Blick entlang der Hauptachse an eine Schneeflocke denken lässt, findet man in einem näherungsweise S6‐symmetrischen achtkernigen Nickelkomplex (der Ni‐O‐Kern ist im Vordergrund zu sehen; Ni grün, O rot). Der Einschluss als μ6‐koordinierter Peroxoligand im Nickelkäfig stabilisiert diese reaktive Spezies. Weitere Informationen finden Sie in der Zuschrift von A.‐K. Duhme‐Klair, P. H. Walton et al. auf S. 1416 ff. (Für das Hintergrundbild danken die Autoren Prof. K. G. Libbrecht, Caltech.)
Synthesis of bismaleimide‐modified novolac resin/clay nanocomposites using p‐phenylenediamine as swelling agent
Authors: Wang Hongsheng , Zhao Tong , Yu Yunzhao
Published: February 2005

Sodium montmorillonite (Na–MMT) was swollen with protonated p‐phenylenediamine, and the latter was converted to maleamic acid. Intercalation of the swelling agents was confirmed by FTIR, XRD, and TGA data. Exfoliation of the organoclay took place easily in the melt of the Bismaleimide‐modified allylated novolac resin. It is remarkable that, as a result of layer delamination, introduction of 2 phr organoclay MAA–MMT brought in a rise in steady shear viscosity for over two orders of magnitude at low shear rates. Major improvement in thermal stability, flexural strength, and modulus was achieved by incorporation of the exfoliated clay layers, in contrast to the composite using pristine Na–MMT as reinforcement. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 466–474, 2005
Barocalorimetric technique for monitoring pressurized copolymer reactors
Authors: Infante Ramiro , Cisneros Arturo , Rivera Claudia , Alvarez Jesús
Published: February 2005

The problem of on‐line estimation of the conversion and composition evolutions in a pressurized batch copolymer reactor with temperature and pressure measurements was addressed. The estimation model consisted of mass and energy balances with a pressure equation built from phase‐equilibrium considerations. The application of a nonlinear geometric estimation approach yielded the underlying solvability condition with physical meaning, a straightforward estimator construction, and a conventional‐like tuning procedure. The resulting barocalorimetric estimator was an on‐line dynamic measurement processor with a model‐based predictor and a measurement‐driven corrector, and whose implementation did not require the polymerization rates and heat‐transfer coefficient function dependencies. The technique was tested with a representative laboratory styrene–butadiene system. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 475–482, 2005
Monte Carlo simulation of sequence distributions of acrylonitrile copolymers
Authors: Hou Chen , Sun Chun‐feng , Ying Liang , Wang Cheng‐guo
Published: February 2005

A Monte Carlo simulation examining the effect of monomer ratios on the composition and sequence distribution of acrylonitrile(AN) copolymers with N‐vinyl pyrrolidone (NVP), itaconic acid (IA), and acrylic acid (AA) as comonomers has been developed. The Kelen–Tudos method was used to estimate monomer reactivity ratios. The results of the simulation are consistent with the academic conclusion and are as foreseen by the experimental data. The average number of NVP identical monomers in a sequence length of AN/NVP copolymer chain increases continuously and the average number of AN identical monomers in a sequence length shows a prominent decrease with an increase of NVP concentration in the feed. Changes in the monomer average number of AN/IA and AN/AA copolymers in a sequence length were the same as those of AN/NVP copolymer with an increase of comonomer concentration in the feed. The optimum weight ratio of AN with comonomers for manufacturing carbon fibers is 98/2. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 483–488, 2005
Poly(dimethylsiloxane) coatings for controlled drug release. III. Drug release profiles and swelling properties of the free‐standing films
Authors: Gao Zongming , Nahrup Julia Schulze , Mark James E. , Sakr Adel
Published: February 2005

Previous reports in this series have described the preparation of stable poly(dimethylsiloxane) (PDMS) latices suitable for spray‐coating of drug tablets, as well as the mechanism of associated crosslinking reactions in PDMS emulsions. In the present investigation, in vitro evaluations were performed to study the effects of the amount of channeling agents, the addition of colloidal silica, and the pH of the dissolution media used. The study involved hydrochlorothiazide (as a marker drug) released from compressed tablets, which had been spray coated using PDMS latices with various polyethylene glycol (PEG) loadings as channeling agents. The dissolution results showed that coated tablets containing up to 25% (w/w dps) PEG could have constant release rates. Higher amounts of PEG resulted in nonlinear release patterns. The addition of colloidal silica decreased the rates of drug release. The pH of dissolution media affected the structures of the exposed PDMS films. Swelling tests were carried out to determine water uptake. Scanning electron microscopy and density measurements showed that the films obtained after soaking in higher‐pH media were more condensed, with corresponding changes in drug‐release rates. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 494–501, 2005
Immobilization of invertase in conducting polypyrrole/PMMA‐co‐PMTM graft copolymers
Authors: Yildiz Hüseyin Bekir , Kiralp Senem , Toppare Levent , Yağci Yusuf
Published: February 2005

In this study, invertase was immobilized in copolymer electrodes constructed. Three different types of polymethyl methacrylate‐co‐polymethyl thienyl methacrylate matrices were used to obtain copolymers that were characterized by FT‐IR spectroscopy. Immobilization of enzymes was carried out by the entrapment of the enzyme in conducting polymer matrices during electrochemical polymerization of pyrrole through thiophene moieties of polymers. Immobilization of the enzyme was achieved by application of 1.0 V constant potential on a platinum electrode for 30 min in solution. The effects of temperature and pH on the activity of the enzyme electrodes were examined and operational stability studies were done. The changes in the maximum reaction rate and the variations in the Michaelis–Menten constant were studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 502–507, 2005
Linear polymers with sulfur in the main chain III. Synthesis of polythioesters by polycondensation of bis(4,4′‐mercaptophenyl)sulfide with various acid dichlorides and their properties
Authors: Hirano Hiroshi , Watase Seiji , Tanaka Mitsuaki
Published: February 2005

Synthesis and properties of sulfur‐containing linear polythioesters derived from bis(4,4′‐mercaptophenyl)sulfide (MPS) and various acid dichlorides (AC) have been studied to evaluate the effect of the thioester group in comparison with corresponding linear polyesters. Polycondensations between MPS and azelaoyl chloride (AZC) chosen as a model reaction system were investigated under various conditions by solution polycondensation, to find optimal conditions to get high molecular weight and quantitative yield. The obtained polymer using chloroform as a solvent indicated the highest molecular weight, determined by gel permeation chromatography (GPC). Thus the polythioesters from MPS and AC were synthesized under the above‐mentioned conditions. The thermal properties of polythioesters including the MPS moiety were evaluated by thermogravimetry/differential thermal analysis (TG/DTA), and differential scanning calorimetry (DSC). Those indicated that the polythioesters including the MPS moiety were crystalline polymers with relatively high heat resistance. These polythioesters were found to show an odd–even effect with the glass transition temperature, melting point, and oxygen permeability based on the methylene numbers. The tensile strength and storage modulus decreased with the number of methylene units. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 508–515, 2005
Ethyl methacrylate grafted on two starches as polymeric matrices for drug delivery
Authors: Echeverria I. , Silva I. , Goñi I. , Gurruchaga M.
Published: February 2005

The use of copolymers grafted on starch for controlled‐release technology is an interesting proposal, since a modification of a natural polymer is more suitable than synthetic polymers because of its biocompatibility and biodegradability. The aim of this paper is to synthesize acrylic polymers grafted on carbohydrates to investigate the release kinetic of different solubility drugs from polymeric matrix systems and to observe the effect of grafted copolymers and drug solubility on the release mechanism. Copolymer variables such as carbohydrate content, stereoregularity of grafted chains, particle size, morphology, sensitivity to hydration, and rheological properties are discussed. Tablets were prepared by direct compression of the graft copolymer and drug. The drugs' release in vitro kinetics was studied by dissolution testing. Drug release from tablets depends on polymer matrix, polymer content, drug, and pH. An increase in drug solubility results in an increase in the rate of dissolution, as in the case of a poor hydrophilic matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 523–536, 2005
Reactive blends of epoxy resin (DGEBA) crosslinked by anionically polymerized polycaprolactam. II. Mechanical and electrical properties
Authors: Gupta Alka , Singhal Reena , Nagpal A. K.
Published: February 2005

Various reactive blends of diglycidyl ether of bisphenol A (DGEBA)/polycaprolactam were synthesized by anionic polymerization at 140°C, conducted by sodium hydride catalyst, a strong base, along with N‐acetyl caprolactam as a cocatalyst. The experiments were performed to study the effect of composition on the mechanical and electrical properties of the reactive blends, such as tensile properties, flexural properties, Izod impact strength, Rockwell hardness, and volume resistivity. It was observed that the DGEBA was crosslinked by the polycaprolactam through the rapid reaction of the oxirane group with amide nitrogen. The heat of reaction and heat‐deflection temperature of the reactive blends increased with increasing DGEBA content from 50 to 80 wt %, and increased dramatically above 70 wt % DGEBA content. The mechanical and electrical properties of the reactive blends increased with increasing DGEBA content from 50 to 80 wt %. Substantial increases in these properties were observed above 70 wt % DGEBA content in the reactive blends. SEM studies revealed that the reactive blends show a multiphase system with an increase in the DGEBA content from 50 to 80 wt % as the mixing of the two phases increased. The reactive blend Ep80Ca20, with 80 wt % DGEBA content, resembles a single‐phase system because of better mixing of the two phases; as a result, this reactive blend showed the highest mechanical and electrical properties. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 537–549, 2005
Electrospinning of nanofibers
Authors: Subbiah Thandavamoorthy , Bhat G. S. , Tock R. W. , Parameswaran S. , Ramkumar S. S.
Published: February 2005

Nanotechnology is the study and development of materials at nano levels. It is one of the rapidly growing scientific disciplines due to its enormous potential in creating novel materials that have advanced applications. This technology has tremendously impacted many different science and engineering disciplines, such as electronics, materials science, and polymer engineering. Nanofibers, due to their high surface area and porosity, find applications as filter medium, adsorption layers in protective clothing, etc. Electrospinning has been found to be a viable technique to produce nanofibers. An in‐depth review of research activities on the development of nanofibers, fundamental understanding of the electrospinning process, and properties of nanostructured fibrous materials and their applications is provided in this article. A detailed account on the type of fibers that have been electrospun and their characteristics is also elaborated. It is hoped that the overview article will serve as a good reference tool for nanoscience researchers in fibers, textiles, and polymer fields. Furthermore, this article will help with the planning of future research activities and better understanding of nanofiber characteristics and their applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 557–569, 2005
Novel thermally stable poly(ether imide ester)s from 2,6‐bis (4‐aminophenoxy) pyridine
Authors: Mehdipour‐Ataei Shahram , Amirshaghaghi Ahmad
Published: February 2005

2,6‐Bis (4‐aminophenoxy) pyridine was prepared via reaction of 4‐aminophenol with 2,6‐dichloropyridine in the presence of potassium carbonate in N‐methyl‐2‐pyrrolidone (NMP). This pyridine‐based ether diamine was reacted with two moles of trimellitic anhydride to synthesize related diimide‐diacid (DIDA). A high temperature solution polycondensation reaction of DIDA with different diols in the presence of triethylamine hydrochloride in dichlorobenzene resulted in different poly(ether imide ester)s. The monomer and polymers were fully characterized, and the physical and thermal properties of the polymers were studied. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 570–576, 2005
Investigation of the self‐association behavior of a thermosensitive copolymer with lower critical solubility temperature near human heat by dynamic laser light scattering
Authors: Yin Weisi , Yang Hu , Zhang Xueqin , Wang Zhiliu , Ding Yanwei , Zhang Guangzhao , Cheng Rongshi
Published: February 2005

The special thermosensitive copolymer with lower critical solubility temperature near human heat of 37°C in aqueous solution has been prepared successfully by copolymerizing N‐isopropylacrylamide (NIPAM) and N‐isopropylmethacrylamide (NIPMAM) randomly at an appropriate monomer ratio. The self‐association behavior of the poly[NIPAM‐ran‐NIPMAM] copolymer has been studied by dynamic laser light scattering (DLLS) at a concentration higher than the critical concentration of the self‐association calculated from viscosity data according to cluster theory. The effect of the concentration and temperature on the self‐association behavior in water has been discussed respectively. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 583–588, 2005