Die Algenflora der Schirmacheroase (Ostantarktika)
Die Algenflora der schirmacheroase (Ostantarktika) , Die Algenflora der schirmacheroase (Ostantarktika) , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی
Materials Literature
文献浏览
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
Evaluation of the area under linear loss modulus‐temperature curves
Abstract The area under the linear loss modulus‐temperature curves, LA, has been shown to be related to the chemical composition of the material. In addition, it can be significantly affected by morphology in multicomponent polymer systems. To characterize LA quantitatively, base‐line corrections for instrumental cont…
Thermal degradation of EVA and EBA—A comparison. III. Molecular weight changes
Abstract This is the third in a series of papers in which the thermal degradation of ethylene‐vinyl acetate (EVA) and ethylene‐butyl acrylate (EBA) copolymers are compared. The EBA samples contained 0.8, 1.6, and 5.4 mol % butyl acrylate (BA), respectively, and the EVA samples 1.2 and 6.7 mol % vinyl acetate (VA). The…
Thermal degradation of EVA and EBA—A comparison. II. Changes in unsaturation and side group structure
Abstract This is the second in a series of papers in which the thermal degradation of ethylene‐vinyl acetate (EVA) and ethylene‐butyl acrylate (EBA) copolymers are compared. The EBA samples contain 0.8, 1.6, and 5.4 mol % butyl acrylate (BA), respectively, and the EVA samples 1.2 and 6.7 mol % vinyl acetate (VA). The…
Surface properties of commercial polymer films following various gas plasma treatments
Abstract Surface properties of a number of commercial thermoplastic polymer films were investigated before and after brief exposures to RF induced, low temperature gas plasmas. Water wettability and adhesion of vapor deposited aluminum to thin films (8–12 micron) of polyethylene, polypropylene, polyester, polysulfone,…
Thermal degradation of EVA and EBA—A comparison. I. Volatile decomposition products
Abstract This is the first in a series of papers in which structural changes during thermal degradation of ethylene‐vinyl acetate (EVA) and ethylene‐butyl acrylate (EBA) copolymers are compared. EVA, containing 11.4 mol% vinyl acetate (VA) and EBA, containing 5.4 mol% butyl acrylate (BA), were pyrolyzed at 280°C in ni…
Preparation and characterization of low‐halogen and nonhalgoen fire‐resistant low‐smoke (FRLS) cable sheathing compound from blends of functionalized polyolefins and PVC
Abstract An attempt is made to develop a novel series of cable sheathing compounds with variation in chlorine content and sufficient fire retardance and unique low‐smoke characteristics. These are prepared by blending PVC and functionalized polyolefins in different compositions. PE and EPDM have been functionalized by…
The primary structure of the glutamic acid‐specific protease ofStreptomyces griseus
The amino acid sequence and part of the DNA sequence of a glutamic acid-specific serine protease from Streptomyces griseus is reported. This protease is shown to be homologous with other serine proteases. An improved purification protocol for this enzyme is described.
The crystal structure of fructose‐1,6‐bisphosphate aldolase fromDrosophila melanogaster at 2.5A˚resolution
The structure of fructose-1,6-bisphosphate aldolase from Drosophila melanogaster has been determined by X-ray diffraction at 2.5 A resolution. The insect enzyme crystallizes in space group P2(1)2(1)2(1) with lattice replacement with rabbit muscle aldolase as a search model has been employed to solve the structure. To…
Diamond synthesis by microwave plasma chemical vapor deposition using graphite as the carbon source
We report on the growth of high-quality diamond using a microwave plasma chemical vapor deposition (CVD) system in which the feed gas contains no hydrocarbons, but instead the source of carbon is a graphite piece which resides within the plasma volume. Results of experiments using this technique by itself and in combi…
Competition between planar and nonplanar structure in alkali hexamers: The example ofLi6
The optical-absorption spectrum of ${\mathrm{Li}}_{6}$ has been observed by depletion spectroscopy in the 400--700-nm range. The experimetnal results are compared with theoretical spectra calculated for the three ${\mathrm{Li}}_{6}$ structures in competition and we have been able to unambiguously determine the most st…
Structural and optical properties of ferroelectric Bi4Ti3O12 thin films by sol-gel technique
Ferroelectric thin films of Bi4Ti3O12 were fabricated on several types of substrates, including quartz, steel plates, and indium-tin-oxide coated glass slides, by sol-gel technique. Crystalline, transparent, and crack-free films of 5000 Å thickness were fabricated by spinning and post-deposition annealing at a tempera…
Optical conductivity of the stable icosahedral quasicrystalAl63.5Cu24.5Fe12
The optical properties of the stable icosahedral quasicrystal ${\mathrm{Al}}_{63.5}$${\mathrm{Cu}}_{24.5}$${\mathrm{Fe}}_{12}$ have been measured from 40 to 25 000 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ at 300 and 80 K. Unlike metallic glasses with a Drude spectrum with strong elastic scattering by disorder, or se…
Interface Properties of Thin YBa2Cu3O7–x Films
Abstract Structures and stability ranges of the YBa 2 Cu 3 O 7–x interface were studied with AES, SIMS, XPS, and TEM. For silicon substrates, the formation of Ba silicates can be detected which even at T = 550 K leads to reduced T c values and non‐epitaxial growth of YBa 2 Cu 3 O 7–x (YBCO). Yttria stabilized zirconia…
A Novel Probe Size Measurement Method for a Fine Electron Beam
A novel electron beam (EB) spot size measurement method is proposed. In this method, EB spot size is obtained from the relationship between the width of the trenches in the reference sample and the intensity profile of backscattered electrons. Selective chemical etching of a GaAlAs/GaAs superlattice produces an ideal…
Two-dimensional transformer modeling taking into account the edge effects by introduction of a correction factor
The authors provide a detailed loss computation of a sheet wound transformer. The aim is to develop a simplified two-dimensional model in which 3-D effects due are introduced by correction factors. The present solution is based on analytical computation of extra losses in bus bars, numerical determination of bus bar s…
Stacked transformer cores using amorphous POWERCORE strip
The potential use of POWERCORE strip for the fabrication of low-loss stacked cores was investigated. Two three-phase transformer cores having different joint configurations were assembled and tested (core A: 90 degrees butt and lap T and corner joints; core B: 45-90 degrees T-joints and 45 degrees mitred corner joints…
Eine Antiperowskitstruktur bei ternären Tetrathiafulvalen‐Salzen: Aufbau, Verzerrung und antiferromagnetische Ordnung
Rhomboedrisch verzerrt aufgrund der Form der organischen Ionen ist die Antiperowskitstruktur aller vier ternären Salze 1 , die durch Elektrokristallisation der Komponenten Tetrathiafulvalen (TTF), Tetrabutylammoniumhalogenohexamolybdat und Tetrabutylammoniumhalogenid erhalten wurden. Die verbleibende dreizählige Symme…
Studies of Polymer Solvation by Dielectric Relaxation Spectroscopy IV:Polyvinylpyrrolidone in Urea Derivatives at Different Temperatures
Abstract The dielectric spectrum is measured up to 72 GHz of solutions of polyvinylpyrrolidone (PVP) in tetramethylurea (TMU), dimethylethylene urea and dimethylpropylene urea. Concentrations are up to a monomole fraction of 0.65 (PVP 1200) or 0.5 (PVP 40 000). Measuring temperatures are 20CC for all systems and addit…
Ion implantation of polymers for electrical conductivity enhancement
Ions in the mass range from H to Xe have been used at energies from a few keV to more than a GeV to cause atomic rearrangement and consequent formation of conducting grains of carbonized material in several polymers. Generally, the conductivity increases dramatically-- by several orders of magnitude--until finally dem…