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971.
Zhang Z Wang J Yuan H Gao Y Liu D Song L Xiang Y Zhao X Liu L Luo S Dou X Mou S Zhou W Xie S 《The journal of physical chemistry. B》2005,109(39):18352-18355
At a low temperature of 450 degrees C, ZnS nanoribbons have been synthesized on Si and KCl substrates by a simple chemical vapor deposition (CVD) method with a two-temperature-zone furnace. Zinc and sulfur powders are used as sources in the different temperature zones. X-ray diffraction (XRD), selected area electron diffraction (SEAD), and transmission electron microscopy (TEM) analysis show that the ZnS nanoribbons are the wurtzite structure, and there are two types-single-crystal and bicrystal nanoribbons. Photoluminescence (PL) spectrum shows that the spectrum mainly includes two parts: a purple emission band centering at about 390 nm and a blue emission band centering at about 445 nm with a weak green shoulder around 510 nm. 相似文献
972.
A new kind of multilayer of didodecyldimethylammonium bromide (DDAB) and 1:12 phosphomolybdic anions (PMo12) was achieved on the surface of a wax-impregnated graphite (WIG) electrode by ion exchange and electrostatic interaction.
The characterization and electrochemical behavior of the multilayer films of DDAB/PMo12 is described in detail. The chemically modified electrode was shown to exhibit an excellent electrocatalytic activity toward
the reduction of BrO3
– anion in 0.5 M H2SO4 and possesses several attractive features, such as simple preparation, fast response, good stability, etc.
Electronic Publication 相似文献
973.
In this text, we use inexpensive and natural amino acid, successfully obtained the asymmetric crystallization of three PTCs, [Tis(O~iPr)_(14)(μ_2-O)(μ_3-O)_2(D/L-pGlu)_2](D-PTC-53; L-PTC-53; H2 pGlu=pyroglutamic acid) and [Ti_6(O~iPr)_(14)(μ_2-O)(μ_3-O)_2(D-pGlu)_2][Ti_6(O~iPr)_(14)((μ_2-O)(μ_3-O)_2(L-pGlu)_2](D,L-PTC-53). Interestingly, in situ lactamide reaction starting from glutamic acid to pyroglutamic acid was observed. In addition,the chirality features of these PTCs have been thoroughly discussed.The two enantiomers crys tallize in chiral P21 space group.The optically pure pGlu ligands transform its chirality to the inorganic titanium oxo clusters. As a result, the stack of these inorganic clusters generates homochiral helical chains along the characteristic axial direction.Apart from the microscopic structural analysis, the macroscopic solid-state samples exhibit unusual strong circular dichroism(CD) signals,further verified the homochiral feature of the enantiomers. 相似文献
974.
Rotaxane is a kind of classic supramolecule, which is usually constructed from a number of macrocycles and one axis molecule. Herein, we have expanded the supramolecular structure of [n]rotaxane to offer a precise definition of (pseudo)[n,m]rotaxane for accurately describing the two kinds of (pseudo)rotaxanes structures, which are self‐assembled from cucurbit[7/8]uril (CB[7/8]) and viologen‐naphthalene derivative, respectively. Furthermore, these CB‐based pseudorotaxanes exhibit varied photophysical properties, stimuli‐responsive behavior triggered by competitive guest, and self‐sorting behavior. 相似文献
975.
As a consequence
of their excellent barrier properties vinyl chloride/vinylidene chloride copolymers
have long been prominent in the flexible packaging market. While these polymers
possess a number of superior characteristics, they tend to undergo thermally-
induced degradative dehydrochlorination at process temperatures. This degradation
must be controlled to permit processing of the polymers. Three series of N-substituted
maleimides (N-alkyl-, N-aralkyl, and N-aryl) have been synthesized, characterized
spectroscopically, and evaluated as potential stabilizers for a standard vinyl
chloride/vinylidene chloride (85 mass%) copolymer. As surface blends with
the polymer, these compounds are ineffective as stabilizers. However, significant
stabilization may be achieved by pretreatment of the polymer with N-substituted
maleimides. The most effective stabilization of the polymer is afforded by
N-aralkyl- or N-arylmaleimides, most notably, N-benzylmaleimide and N-p-methoxyphenylmaleimide. 相似文献
976.
Xin Yang Chuan Dong Jun Zhang Yan-sheng Wei Wei-Jun Jin Chang-song Liu 《Microchemical Journal》1997,57(3):294-304
Six polycyclic aromatic hydrocarbons (PAHs) are studied by chemical deoxygenation microemulsion-stabilized room temperature phosphorimetry with sodium sulfite as an oxygen scavenger and thallous nitrate as a heavy atom perturber in sodium dodecyl sulfate medium. Several factors influencing room temperature phosphorescence such as the concentration of sodium dodecyl sulfate, the heavy atom concentration, the pH, and the concentration of sodium sulfite are discussed and the quenching effect of NO2−on room temperature phosphorimetry of PAHs was compared in the microemulsion and micelle media. 相似文献
977.
978.
N-(α-Benzotriazolylalkyl)arylacetamides, readily available from an arylacetamide, an aldehyde and benzotriazole, undergo intramolecular cyclization under acidic conditions to give 1-aryl-1,4-dihydro-3(2H)-isoquinolinones in good to excellent yields. Similarly, 2-(benzotriazol-1-yl)-2-(o-hydroxyphenyl)ethanols, obtained by lithiation of 2-(benzotriazol-1-ylmethyl)phenols followed by quenching with aldehydes or ketones, eliminate a molecule of water and a molecule of benzotriazole yielding 2-substituted and 2,3-disubstituted benzofurans. 相似文献
979.
Theoretical and Mathematical Physics - The initial-boundary value problems for the matrix Lakshmanan–Porsezian–Daniel system are studied by utilizing the Fokas unified transform... 相似文献
980.
Acta Mathematicae Applicatae Sinica, English Series - Joint analysis of multiple phenotypes can have better interpretation of complex diseases and increase statistical power to detect more... 相似文献