Materials Literature
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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.
The infrared spectrum of a sample of potassium-fluor-richterite (PFR) is compared with that of a synthetic potassium-richterite having a similar OH-F content. The PFR spectrum shows an additional absorption band with respect to the synthetic sample, and this is assigned to a configuration involving Tl 71Al. The spectr…
Abstract Careful control of experimental conditions in the cathodic electropolymerization of acrylonitrile allows the grafting of thin polymer films, on conducting surfaces offering electrons easily mobilized at a relatively low potential. Matching relative polarity and donicity of solvent and monomer expands the appl…
A study of the magnetic anisotropy of single-crystal YFe 11 Ti and of its hydride is reported. The measurements were performed on a vibrating-sample and a torsion magnetometer on field-oriented single-crystal and powder samples. The temperature dependence of the magnetic anisotropy constants K 1 and K 2 was determined…
Extraction of aluminum with 1 M KCl has been adopted as a standard method for determining salt exchangeable forms of Al from acid soils. We examined the possibility of Al precipitation during KCl extraction in soil samples dominated by Al-humus complexes by comparing Al release rates between non-treated and KCl-treate…
Electron energy-loss spectra of V 2 O 3 of the paramagnetic metallic (PM) and antiferromagnetic insulating (AFI) phases have been measured by a high-resolution transmission electron energy-loss spectroscopy (EELS) technique. An excitation at about 1 eV was previously observed in both the PM and AFI phases by an optica…
Microphase separation in a blend of A−B and C−B block copolymers with strong A−B and C−B incompability is considered in the strong segregation regime. It is assumed that the length of the B block is always much larger than the lengths of A and C blocks, so the complex spherical micelles containing shorter A and longer…
Abstract This paper deals with a complex investigation of carbon and glass fiber reinforced plastics (CFRP, GFRP) and hybrid composites based on epoxy compositions and used in Salyut‐type spacecraft that had spent up to 1501 days in outer space. The samples with an unprotected surface and the samples exposed to outer…
The effect of amino (trimethylene phosphonic acid), (ATMP), molybdate and Zn 2+ on the inhibition of corrosion of mild steel in a neutral aqueous environment containing 60 ppm Cl ‐ has been evaluated by the weight ‐ loss method. It is found that the formulation consisting of 50 ppm ATMP, 300 ppm MoO 4 2‐ and 50 ppm Zn…
Because doping ions are mainly surrounded by solvent molecules in the early stages of sol—gel processing, the luminescence of rare-earth ions in such an environment is known to be very similar to that observed in aqueous solutions. Thus we performed a molecular dynamics simulation of the trivalent europium in aqueous…