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71.
TAG (MLM) with medium-chain FA (MCFA) at the 1,3-positions and long-chain FA (LCFA) at the 2-position, and TAG (LMM) with LCFA at the 1(3)-position and MCFA at 2,3(1)-positions are a pair of TAG regioisomers. Large-scale preparation of the two TAG regioisomers was attempted. A commercially available FFA mixture (FFA-CLA) containing 9-cis, 11-trans (9c, 11t)- and 10t,12c-CLA was selected as LCFA, and caprylic acid (C8FA) was selected as MCFA. The MLM isomer was synthesized by acidolysis of acyglycerols (AG) containing two CLA isomers with C8FA: A mixture of AG-CLA/C8 FA (1∶10, mol/mol) and 4 wt% immobilized Rhizomucor miehei lipase was agitated at 30°C for 72 h. The ratio of MLM to total AG was 51.1 wt%. Meanwhile, LMM isomer was synthesized by acidolysis of tricaprylin with FFA-CLA: A mixture of tricaprylin/FFA-CLA (1∶2, mol/mol) and 4 wt% immobilized R. miehei lipase was agitated at 30°C for 24 h. The ratio of LMM to total AG was 51.8 wt%. MLM and LMM were purified from 1,968 and 813 g reaction mixtures by stepwise short-path distillation, respectively. Consequently, MLM was purified to 92.3% with 49.1% recovery, and LMM was purified to 93.2% with 52.3% recovery. Regiospecific analyses of MLM and LMM indicated that the 2-positions of MLM and LMM were 95.1 mol% LCFA and 98.3 mol% C8 FA, respectively. The results showed that a process comprising lipase reaction and short-path distillation is effective for large-scale preparation of high-purity regiospecific TAG isomers.  相似文献   
72.
We report the initial results of GaAs and GaInP solar cells grown by all solid-state molecular-beam-epitaxy (MBE) technique. For GaAs single-junction solar cell, with the application of AlInP as the window layer and GaInP as the back surface field layer, the photovoltaic conversion efficiency of 26% at one sun concentration and air mass 1.5 global (AM1.5G) is realized. The efficiency of 16.4% is also reached for GaInP solar cell. Our results demonstrate that the MBE-grown phosphide-contained III-V compound semiconductor solar cell can be quite comparable to the metal-organic-chemical-vapor-deposition-grown high-efficiency solar cell.  相似文献   
73.
74.
It is said that we cannot have color constancy in a photograph. The concept of recognized visual space of illumination (RVSI) asserts that chromatic adaptation occurs when one perceives the illumination that is filling a space and not the objects in the space. It predicts then that if one perceives a 3D scene in a photograph, then color constancy will occur in the photograph. In this work, a dimension‐up (D‐up) viewer was developed to perceive a 3D scene on a 2D photograph, and the effect of chromatic adaptation was measured by the color appearance of a gray patch placed at the center of the photograph. Subjects saw the patch as a vivid color when they saw a photograph that had been taken under colored illumination, which is a normal experience in a real space observation. When the color appearance was measured by the elementary color naming method, the amount of chromaticness of the patch in percentage and the apparent hue were very similar to those observed in the 2‐room technique, thus confirming the prediction by the RVSI theory.  相似文献   
75.
76.
Biofuel cells (BFCs) that produce electrical energy from organic resources through enzymatic reactions have been attracting significant attention. Owing to the high electrical conductivity of carbon nanotubes (CNTs), their modification on the electrode surface of a BFC is expected to increase the current, and their high specific surface area may be useful in increasing the power output. Previously, we constructed a biocathode by immobilizing multicopper oxidase from Pyrobaculum aerophilum (McoP) with a carbon nanotube binding peptide (CBP) sequence on the CNTs. This resulted in higher current densities than when using enzymes without CBP sequences. However, owing to the randomly stacked CNTs on the surface of the electrodes, their conductive properties were impaired and performance as biocathodes was poor. Herein, we constructed a biocathode in which single-walled CNTs (SWCNTs) were oriented one-dimensionally and McoP is immobilized on the surface of an SWNCT via CBP. The current density was successfully increased by two-fold by orienting the CNTs and orienting and immobilizing McoP on their surfaces. This technology provides insights into the development of biodevices with controlled orientation of both the SWCNTs and enzymes immobilized on their surfaces.  相似文献   
77.
Unpolarized optical spectra were measured in the wavelength range 322–1666 nm by the diffuse reflection technique from spinel powders synthesized in the system MgAl2O4–MgCr2O4. The spectra were interpreted by the crystal-field theory on the basis of trigonally distorted spinel octahedra with D3d symmetry. For chromium-rich solid solutions, including the MgCr2O4 end-member, results after peak fittings showed octahedral D3d local symmetry around Cr3+ ions, identical to the crystallographic site symmetry. For chromium-poor solid solutions, however, octahedral C3v local symmetry was suggested around Cr3+ ions, different from the D3d crystallographically expected.  相似文献   
78.
We demonstrate that domain structure of single-layer graphene grown by ambient pressure chemical vapor deposition is strongly dependent on the crystallinity of the Cu catalyst. Low energy electron microscopy analysis reveals that graphene grown using a Cu foil gives small and mis-oriented graphene domains with a number of domain boundaries. On the other hand, no apparent domain boundaries are observed in graphene grown over a heteroepitaxial Cu(111) film deposited on sapphire due to unified orientation of graphene hexagons. The difference in the domain structures is correlated with the difference in the crystal plane and grain structure of the Cu metal. The graphene film grown on the heteroepitaxial Cu film exhibits much higher carrier mobility than that grown on the Cu foil.  相似文献   
79.
概述了从长链烷基二甲基叔胺及其盐酸盐和环氧氯丙烷或其他连接剂在温和条件下合成新型双烷基双季铵盐型阳离子表面活性剂的方法,产品的表面活性以及烷基链长、连接基团结构对产物表面活性的影响。  相似文献   
80.
Supramolecular architectures that are built artificially from biomolecules, such as nucleic acids or peptides, with structural hierarchical orders ranging from the molecular to nano-scales have attracted increased attention in molecular science research fields. The engineering of nanostructures with such biomolecule-based supramolecular architectures could offer an opportunity for the development of biocompatible supramolecular (nano)materials. In this review, we highlighted a variety of supramolecular architectures that were assembled from both nucleic acids and peptides through the non-covalent interactions between them or the covalently conjugated molecular hybrids between them.  相似文献   
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