Materials Literature
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。
A new ultramicrohardness tester for a load range between 2×10−2 and 5×10−5 N is described. The instrument is operated inside a scanning electron microscope. Load is applied and measured by means of electrical signals thus making fully automized experiments possible. Typical examples demonstrate the capability of the d…
Abstract Two crystal modifications have been found for poly(3,3‐bisethoxymethyl oxetane) [poly‐ (BEMO)] by wide‐angle x‐ray powder diffraction and differential scanning calorimetry, while only one modification has been found for poly(3,3‐bisazidomethyl oxetane) [poly(BAMO)]. Melting temperatures for the two polymers w…
Measurements of the mechanical threshold, or threshold stress, are reported on quasi-statically and dynamically deformed copper and Nitronic 40. Results for copper show that the increase of the threshold stress with strain rate is similar to that of the flow stress. In Nitronic 40 the results show that the ratio of th…
A new cardiac glycoside "vijaloside" in addition to well known cardenolide, asperosid (digitoxigenin-2',3'-di- O-methylglucopyranoside) have been isolated and identified from the roots of STREBLUS ASPER. Repeated chromatgraphic manipulations and spectral analysis (IR, (1)H-NMR, (13)C-NMR and Mass), suggested the struc…
Abstract Reactions between hydroxy-Al ions and orthosilicic acid as influenced by citric acid were studied at an initial Si concentration of 1.6 × 10 −3 M, Si/Al molar ratios of 0.5 and 1.0, OH/Al molar ratios of 1.0-3.0, and citric acid/Al molar ratios of 0-0.3. In the absence of citric acid and at OH/A1 ratios of 1.…
Temperature variation of the dielectric permittivity, refractive indices, birefringence, density and order parameter of nematic liquid crystalline mixtures 1333, RO-TN 605, 2855, E-43 and ZLI-1565 are reported. The dielectric studies are in the frequency range 1 KHz to 3.5 MHz. The dielectric permittivity component pa…
Filamentary thermal breakdown is discussed on the basis of experimental results on the electrical conduction just prior to breakdown in polyimide (PI) and polyethylene (PE) with a dc ramp voltage applied at 90°C. In PI, the pre-breakdown current was almost proportional to the electrode area S till about 100 µs before…
Ten taxa of marine diatoms from SE. or NE. Australia are described or redescribed, and their characters are supplemented by fine-structural and developmental data. One genus (Pseudoguinardia von Stosch), one species (Pseudoguinardia recta von Stosch), and two varieties (Odontella retiformis var. trigona von Stosch and…
The low‐temperature tetragonal‐monoclinic phase transformation in yttria‐doped tetragonal zirconia polycrystalline ceramics which results in strength degradation was found to be reversible. The retransformed ceramic has properties equivalent to those of the as‐sintered ceramic.
Abstract A model incorporating a rough (disordered) crystal growth surface is capable of treating many of the observations and measurements on the crystal growth of short chains of poly(ethylene oxide) from the melt. A simple preliminary treatment if presented which aims primarily to analyze the growth rate data withi…
Abstract MSn(OH) 6 (M = Mg, Co, Zn, Mn, Cd, Ca, Sr, and Ba) and their solid solutions were synthesized by coprecipitation from aqueous solutions of Na 2 Sn(OH) 6 complex and MCl 2 . MSnO 3 and their solid solutions were prepared by thermal decomposition of these MSn(OH) 6 precipitates. Coprecipitation procedures were…
Abstract Die stereoselektive Synthese der all‐ trans ‐7‐Alkylperhydro‐2‐phenanthrenole 15a – f in 11 Stufen und 28 flüssigkristalline Ester 16 von 15a – f werden beschrieben, daneben einige weitere Derivate der 7‐Alkylperhydro‐2‐phenanthrenole. Vom Ester 16ec wurde eine Röntgenstrukturanalyse durchgeführt.
Maleylpyruvate, the ring fission product of gentisic acid, was found to be isomerized to fumarylpyruvate without a requirement for glutathione by an enzyme activity found in cell extracts of m-hydroxybenzoate-grown Bacillus megaterium 410. The isomerization reaction was detected as a shift in the absorbance maximum fr…
The electrochromic properties of film electrodes of lutetium, erbium, gadolinium, and ytterbium diphthalocyanines in contact with ethylene glycol solutions have been studied. The stability of the electrochromic film under electrochemical cycling in this medium is at least three orders of magnitude better than that in…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTAdiabatic photodehydroxylation of 9-phenylxanthen-9-ol. Observation of carbocation fluorescence in neutral aqueous solutionPeter Wan, Keith Yates, and Mary K. BoydCite this: J. Org. Chem. 1985, 50, 16, 2881–2886Publication Date (Print):August 1, 1985Publication History Publi…
The effect of phonon grain-boundary scattering on the lattice thermal conductivity λL of PbSnTe and PbGeTe has been investigated theoretically as a function of grain size and doping. It is concluded that for optimally doped thermoelectric material with a mean grain size of 0.5 μm, the reductions in λL of PbSnTe and Pb…
To investigate the content of amorphous forms of Fe, Al and Si in podzolic soils, the B horizons from 54 Humo-Ferric Podzols and 24 Eluviated Dystric Brunisols were sampled in northern Ontario. Dithionite-citrate-bicarbonate (DCB) Fe d and Al d , acid NH 4 -oxalate Fe o , Al o and Si o , Na-pyrophosphate Fe p , Al p a…
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStructural and electronic properties of six-coordinate manganese(III) porphyrin cations. Crystal and molecular structure of bis(N,N-dimethylformamide)(tetraphenylporphinato)manganese(III) perchlorate, [MnIII TPP(DMF)2]+ClO4-Craig L. Hill and Michael M. WilliamsonCite this: I…
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 Stuart F. Cogan, Elizabeth J. Anderson, Timothy D. Plante, and R. David Rauh, "Electrochemical investigation of electrochromism in transparent conducti…
Abstract A linear lattice model without adjustable parameters provides an accurate description of the magnitude and temperature dependence of the thermal conductivity of K c of polyethylene crystals parallel (∥) and perpendicular (⟂) to the chain direction. The model shows that heat is transported principally by phono…