Materials Literature
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The potential energy surfaces for the insertion of a boron atom into CH4 and its consequent processes have been characterized employing MP2 and QCISD methods with the 6-311G(d,p) and 6-311 + + G(d,p) basis sets in order to locate the stationary points, followed by QCISD(T) calculations using a correlation-consistent a…
In this chapter pressure assisted sintering methods will be described. Attention will mainly be paid to sinter forging as a die-wall free uniaxial pressure sintering technique, where large creep strains are possible. Sinter forging is an effective tool to reduce sintering temperature and time and to obtain a nearly th…
A study is reported of the magnetic, electrical, and crystallographic properties of La 1− x Sr x MnO 3 (0.15⩽ x ⩽0.23) epitaxial films grown on single-crystal substrates of (001)ZrO 2 (Y 2 O 3 ) having the fluorite structure and (001)LaAlO 3 having the perovskite structure. It was found that films with close compositi…
A radiation grafted copolymer of polycarbonate (PC) and polystyrene (PS) was used as a compatibilizer of PC/PS melt blends. The compatibility and morphology of PC/PS/PC-g-PS blends were studied by differential scanning calorimetry and scanning electron microscopy. As a consequence of the addition of PC-g-PS, the compa…
Article Wasserfreie Präparationsmethode zum Nachweis von Chloriden bei der Hochtemperaturoxidation in chlorhaltigen Atmosphären / Water-free Methods of Preparation for the Analysis of Chlorides in the High Temperature Oxidation in Chlorine Containing Atmosheres was published on February 1, 1998 in the journal Practica…
Abstract Rubber articles derive most of their mechanical properties from the admixture of reinforcing fillers. Most commonly, carbon black is used as reinforcing filler. If silica is used instead, tyres made with such rubber compounds may exhibit a rolling resistance reduction by ca. 30%, which translates in substanti…
All articles of this category The title compound 3 was obtained in good yield by a two step synthesis starting from 2-formyl-5,10,15,20-tetraphenylporphyrin ( 1 ). Palladium-catalyzed coupling reactions of the alkyne moiety with iodoarenes proceed well, rendering 3 a suitable building block for the synthesis of photoa…
A new model of bubble dynamics is constructed in order to investigate single-bubble sonoluminescence (SBSL). In this model, the effects of non-equilibrium evaporation and condensation of water vapor at the bubble wall and of thermal conduction both inside and outside a bubble are taken into account. The most important…
CxN compounds were coated on two kind of graphites, natural graphite treated with 94%HN03 solution and the natural graphite without treatment, by chemical vapor deposition. XPS and Raman spectroscopy revealed that these materials were not mixtures of CxN and graphites, but CxN coated-graphites. As anodes of secondary…
The malate dehydrogenase (MDH) from Streptomyces aureofaciens was purified to homogeneity and its physical and biochemical properties were studied. Its amino-terminal sequence perfectly matched the amino-terminal sequence of the MDH from Streptomyces atratus whose biochemical characteristics have never been determined…
Abstract The complex dielectric permittivity of ionic plastic crystal KNO 2 was measured in the frequency range 20‐10 6 Hz and the temperature range 22‐300 K. A small step‐like anomaly of the static dielectric permittivity appeared at the rhombohedral (phase II) to monoclinic (phase III) transition ( T tr2 = 264. 1 K)…
A novel monomer with two N-phenylimide activating groups for the preparation of poly(aryl ether)s was investigated. A poly(aryl ether) was prepared by nucleophilic halide displacement from an aromatic dihalide monomer containing two N-phenylimide groups by sodium salts of bisphenol A. The monomers and the resulting po…
Positive temperature coefficient of resistance (PTCR) barium titanate is the active material in a ceramic sensor which employs piezoresistivity to detect changes in applied stress. High‐purity, chemically prepared barium titanate is donor‐doped with 0.30 at.% lanthanum, and <0.10 at.% of a transition‐metal counterd…
The technically important synthesis of alkyl polyglycosides from fatty alcohols and D-glucose was investigated on a laboratory scale. A new simple method to quantify the rate of this complex reaction by measuring the formation of water is described. The influence of the concentration and the kind of the sulfonic acids…
We have made ultrasonic measurements on several silica aerogels in the previously unstudied region between room temperature and 15 K. We present detailed results for two samples with densities of 360 and 290 $\mathrm{k}\mathrm{g}/{\mathrm{m}}^{3}$ (porosities of 84 and 89%) and sound velocities of a few hundred meters…
The rheological behavior of a short-polyester-fiber-filled polyurethane elastomer composite containing different bonding agents has been studied in the temperature range 120–160°C and in the shear rate range 63–608s−1. The composite with and without bonding agents showed a pseudoplastic behavior which decreased with t…
Abstract Hyalotekite, a framework silicate of composition (Ba,Pb,K) 4 (Ca,Y) 2 Si 8 (B,Be) 2 (Si,B) 28 F, is found in relatively high-temperature (⩾ 500°C) Mn skarns at Långban, Sweden, and peralkaline pegmatites at Dara-i-Pioz, Tajikistan. A new paragenesis at Dara-i-Pioz is pegmatite consisting of the Ba borosilicat…
We report Raman scattering investigations of the structural evolution of Se1−x Ge x glasses for 0 ≤ x ≤ 0.4. The correlation between the 150-280cm−1 spectral range and the boson peak allows one to determine the different stages of this evolution. The comparison of the low-frequency Raman scattering measurements and th…
An NAD-specific glutamate dehydrogenase from Thermus thermophilus HB8 was purified 350-fold by a several-step procedure involving Blue-Sepharose chromatography. The native protein had a molecular mass of approximately 289 kDa, and consisted of six subunits with a molecular mass of 48 kDa each. The optimum pH for the d…
Abstract It is shown that the adjoint group R ° of an arbitrary radical ring R has a series with abelian factors and that its finite subgroups are nilpotent. Moreover, some criteria for subgroups of R ° to be locally nilpotent are given.