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。
Abstract Soil weathering is an important source of nutrient cations and P for development of forested ecosystems, but the rates at which these nutrients are released are not well known. Measurement of weathering products can be used in long‐term (5–10 yr) mesocosm studies to evaluate soil weathering rates. In this stu…
A new class of photochromic compounds, derivatives of 2,3-dihydro-2-spiro-4′-(2′,6′-di-tert-butylcyclohexadienon-2′,5′- one) erimidine is described and their photochromic and thermochromic rearrangements described.
A previous study (Snyder, C. R.; Marand, H.; Mansfield, M. L. Macromolecules 1996, 29, 7508) by the authors suggested that, within the context of the Lauritzen−Hoffman secondary surface nucleation theory, the apportionment factor for the free energy of crystallization (ψ LH ) and the retardation factor due to transpor…
Raman spectra have been recorded from 300--10 K for lanthanide hexachloroelpasolites, ${\mathrm{Cs}}_{2}$${\mathrm{NaLCl}}_{6}$. Electronic Raman-scattering intensity ratios have been calculated using Judd-Ofelt-Axe theory and are in reasonable agreement with experimental results, except for those cases where electron…
The electron-donating property of Na metal-doped MgO (Na/MgO) was studied by the ESR technique. The spin concentration of (CO) n x - ((CO) 2 - and/or (CO) 6 3 - ) radicals formed from adsorbed CO on a Na/MgO surface was much higher than that of the surface paramagnetic center formed by an electron released from sodium…
Abstract A brief discussion of selected synthetic strategies pursued in the field of molecular, macromolecular and supramolecular liquid crystals is made by reviewing some tandem historical events of the past 100 years of activity in this field. This survey will try to suggest the rational for the discovery, evolution…
The synthesis, mesophase morphology and transition temperatures of a series of 1,2,4,5-tetrasubstituted benzenes are described. The compounds have (4-tridecyloxyphenyl)carbonyloxy or (4-tridecyloxyphenyl)ethynyl as the peripheral substituents in all possible combinations ranging from the tetra-ester to the tetra-alkyn…
We have investigated the effects of the sputter-induced roughness on the depth resolution Δz and on the interface position zc obtained by Auger electron spectroscopy (AES) depth profiling of a Ni/Cr multilayer and of an AlAs/GaAs superlattice. We also correlated the escape depth λ with Δz and zc. First, the sputter-in…
Inference of ageing mechanisms becomes a very complex matter in insulations, where the presence of electrical field concentrations, temperature gradients, various insulating materials, inhomogeneities, etc., complicates tremendously any physical investigation. This paper focuses on recent developments in modeling insu…
Epoxidation of oleic acid with oxygen in the presence of benzaldehyde using cobalt(II) tetraphenylporphyrin (Co 2+ -TPP) as catalyst was studied. The results show that high yield of epoxidized oleic acid is obtained by the liquid phase epoxidation of oleic acid in the presence of benzaldehyde using Co 2+ -TPP as catal…
Raman and FTIR reflectance spectroscopies have been used for the characterization of the following zinc corrosion products formed by atmospheric corrosion : (ε-Zn(OH)2, hydrozincite Zn5(CO3)2(OH)6, simonkolleite Zn5Cl2(OH)8,H2O and zinc sulfates ZnSO4,H2O, Zn4SO4(OH)6, 5H2O and Zn4SO4(OH)6,H2O. The samples to analyze…
In this paper is reported the partial hydrophobization of O-(2-sulfoethyl)cellulose (SEC) using 1-bromododecane, 1-bromodecane, and 1-bromododecane with cellulose sulfate (CS), respectively, and characterization of the reaction products by both elemental and spectral analyses. The surface tension, critical micelle con…
Previous temperature programmed desorption (TPD) experiments on reduced TiO2 (001) surfaces have demonstrated that alkynes are converted to the corresponding aromatic products with high selectivity. This reaction also represents the first example of catalytic assembly of carbon–carbon bonds on a metal oxide surface in…
In ${\mathrm{Ce}}_{2}$${\mathrm{Fe}}_{14}$B and ${\mathrm{Ce}}_{2}$${\mathrm{Fe}}_{17}$, cerium is mixed valent and nonmagnetic. Any structural or compositional modification of these intermetallics which induces cerium to become trivalent and develop a local 4f moment should result in compounds with enhanced magnetost…
Ubiquitin is a 76-amino acid protein involved in the targeting for destruction of proteins in the cell. The protein can readily be synthesized chemically affording an extra dimension to studies of protein stability. Ubiquitin with various modifications to the hydrophobic core has been synthesized. In particular, two c…
Representative profiles of the Owena, Egbeda, Alagba, and Balogun series were studied. The Owena soil is formed in amphibolite whereas Egbeda and Balogun soils are formed in biotite gneiss derived parent materials. The Alagba soil is formed in sandstone parent rock. The main objectives were to characterize the soils a…
The adsorption of the hydroxyl (OH) radical on Ni(100), Ni(111), and Fe(110) and coadsorption of OH + O on Ni(100) are treated using an ab initio configuration interaction embedding theory. The metal surfaces are modeled as a 30-atom cluster for Ni(100), a 28-atom cluster for Ni(111), and a 40-atom cluster for Fe(110)…
Experimental solubilities are reported for pyrene dissolved in eight binary mixtures containing 2-methyl-2-butanol and alcohol (1-propanol, 2-propanol, 1-butanol, 2-methyl-1-propanol, 1-pentanol, 2-pentanol, 3-methyl-1-butanol, or 4-methyl-2-pentanol) at 26 °C. Results of these measurements are used to test two mathem…
Cet article fait le point sur l'état actuel des connaissances concernant les résines époxy réticulées par des polyamines, et plus particulièrement sur : - la réticulation ; - la structure et la morphologie des systèmes réticulés et les paramètres qui les influencent; - les relations entre la structure et les propriété…
Three-dimensional scans of residual stress within intact weldments provide insight into the consequences of various welding techniques and stress-relieving procedures. The neutron diffraction method for nondestructive evaluation of residual stresses has been applied to a circumferential weld in a ferritic steel pipe o…