Materials Literature
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An adiabatic scanning calorimeter has been used to investigate the temperature dependence of the enthalpy and the heat capacity near the smectic A (A) to nematic (N) phase transition in mixtures of alkylcyanobiphenyl (nCB) liquid crystals. Mixtures of 8CB + 10 CB with small N-ranges undergo first-order transitions, bu…
Abstract Greenhouse and laboratory experiments were conducted to characterize the K supply and nonexchangeable K release kinetics in calcareous soils. Twelve soils were exhaustively cropped with alfalfa ( Medicago sativa L.) in the greenhouse for 584 d (16 cuttings). Yield, K uptake, and changes in NH 4 OAc exchangeab…
A series of 7-(substituted aryl)-3,5-dihydroxy-6-heptenoic (heptanoic) acids and their lactone derivatives have been prepared and tested for inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase in vitro. A systematic exploration of the structure-activity relationships in this series led to the synthesis of (+…
The glass‐forming region for calcium aluminosilicate glasses has been determined. A number of properties of these glasses (thermal expansion coefficient, glass transformation and dilatometric softening temperature, and refractive index) have been studied. The results of these measurements suggeq that the structures of…
A maximum entropy method (MEM) map of electron density is obtained by maximizing S = -Σ p log p subject to whatever data are available. MEM is derived as the only reconstruction technique that is consistent with simple and general requirements. The method is very widely applicable, but, in this paper, attention is foc…
A simple thermodynamic model describing hydrous silicate melts has been applied to the systems albite-, diopside-, and silica-$$H_{2}O$$. The model is based on the assumption of ideal mixing of hydroxyl groups, $$H_{2}O$$ molecules, and oxygens in the melt. Calculated and experimentally determined freezing-point depre…
The crystallization kinetics of unfilled and glass-reinforced grades of polyphenylene sulfide has been investigated by using differential scanning calorimetry. The maximum rate of crystallization is observed at about 170°C. From the crystallization data, it is recommended that the molding parameters should be so speci…
In this work the reactions taking place during melt mixing of bisphenol-A polycarbonate (PC) with poly(ethylene terephthalate) (PET) were studied by selective degradation of PC sequences, solubility tests, and IR spectroscopy. It was found that exchange reactions between PC and PET took place, contrary to what has bee…
Polyaniline, (4oSN) is found to exhibit a low energy absorption edge beginning near 1800 cm−1 (ca: 0.22 eV), and a strong anion-induced absorption from about 800 to 1200 cm−1. Electrical conductivity has an activation energy of 0.05 (15%) eV consistent with an anion-induced energy gap of about 0.1 eV.
The theoretical basis for the use of paramagnetic agents to enhance proton relaxation is described. Factors of importance in the design of contrast agents are considered. Measurements of changes in T1 and T2 in vitro due to Gd3+-diethylenetriamine pentaacetic acid (DTPA) are used to predict changes in the intensity of…
Gadolinium-DTPA complex (Gd-DTPA) is a potential clinical magnetic resonance (MR) contrast agent that enhances images primarily by decreasing spin-lattice relaxation time (T1) in tissues in which it localizes. This study was designed to determine the immediate tissue distribution of intravenously administered Gd-DTPA…
Get PDF Email Share Share with Facebook Tweet This Post on reddit Share with LinkedIn Add to CiteULike Add to Mendeley Add to BibSonomy Get Citation Copy Citation Text Joseph L. Horner and James R. Leger, "Pattern recognition with binary phase-only filters," Appl. Opt. 24, 609-611 (1985) Export Citation BibTex Endnote…
The dc conductivity of hexagonal boron nitride (BN) and BN‐containing composites was measured as a function of temperature up to 2400°C. The results confirm that at high temperatures BN is an intrinsic semiconductor with an energy gap of 0.99 ± 0.06 aJ (6.2 ± 0.4 eV) at T = 0 K. Extrapolated values for the resistivity…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEPR spectroscopic study of S = 1, 2, and 3 spin states of tris(.mu.-hydroxo)-bridged chromium(III) dimersStefan KremerCite this: Inorg. Chem. 1985, 24, 6, 887–890Publication Date (Print):March 1, 1985Publication History Published online1 May 2002Published inissue 1 March 198…
In photoelectrochemical (PEC) cells based on single junctions of semiconductors with solutions or metals, photopotentials are rarely above 0.6–0.8V. The higher photovoltages needed to drive more energetic reactions require multijunction cells involving multilayer electrodes or series connection of PEC cells. Such PEC…
Abstract With respect to the behavior of Nuclear Pressurized Water Reactor fuel cladding during accidents the oxidation kinetics of Zircaloy‐4 tubing in steam and the related changes in the mechanical properties have been investigated. Short tube sections were exposed to steam between 600 and 1600°C under isothermal a…
Electrochemically active aluminum can be cathodically deposited and anodically stripped from acidic mixtures of 1‐methyl‐3‐ethylimidazolium chloride and aluminum chloride at room temperature. The rates of deposition can be high (25 mA/cm 2 ), and the deposited aluminum can be quantitatively cycled in large amounts (>2…
Abstract Among the perovskite-type oxides examined, SrTiO3 showed a high sensitivity to oxygen in the “lean-burn” region. The resistivity characteristics of the specimen were also investigated in the exhaust gas of propane-oxygen combustion. SrSnO3 is promising for a combustion monitoring sensor.
SUMMARY A mathematical model for soil profile evolution is developed in three parts; respectively for the weathering profile, the organic profile and for the inorganic profile associated with nutrient cycling. Processes modelled are percolation, equilibrium solution, leaching, ionic diffusion, organic mixing, leaf fal…
Two highly purified syntrophic associations resulting in acetogenesis from stearate (SM) and oleate (OM) were obtained from the sludges of a sewage digestor. In both cases, Methanospirillum hungatei together with short, motile, gram-negative, nonfluorescent rods morphologically similar to Syntrophomonas wolfei were id…