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61.
Experimental study of dc and ac transport properties of CuInSe2/ZnO heterostructure is presented. The current-voltage (I-V) and frequency dependent capacitance (C-f) characteristics of CuInSe2/ZnO heterostructure were investigated in the temperature range 160-393 K. The heterostructure showed non-ideal behavior of I-V characteristics with an ideality factor of 3.0 at room temperature. Temperature dependent dc conductivity studies exhibited Arrhenius type behavior and revealed the presence of trap level. The C−2-V plot measured at frequency 50 kHz had shown non-linear behavior. An increase in capacitance with temperature was observed. The capacitance-frequency characteristics exhibited a transition between low frequency and the high frequency capacitance. As the temperature was lowered the transition occurred at lower frequencies. The frequency and temperature dependent device capacitance had shown a defect state having activation energy of 108 meV.  相似文献   
62.
A capillary electrophoresis (CE) method is described for the simultaneous determination of copper and iron after complexation with a readily biodegradable chelating agent, [S,S']-ethylenediaminedisuccinic acid (EDDS), in wood pulp. CE separation was performed in a fused-silica capillary (50 microm i.d.; total length, 65 cm) with an electrolyte containing 25 mM borate buffer and 0.5 mM CTAB at pH 7.0 and an applied voltage of -25 kV. The samples were introduced by applying a 50 mbar pressure for 2 s, and detection of the complexes was monitored at 245 nm. The methodology performance of the methods was evaluated in terms of the linearity, limit of detection (LOD), limit of quantitation (LOQ) and reproducibility. The applicability of the method was demonstrated for the analysis of copper and iron in wood pulp.  相似文献   
63.
CuIn1−xAlxSe2 (CIASe) thin films with x=0.25, 0.5 and 0.65 were prepared by four-source elemental evaporation. The structural and optical properties were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive analysis, and optical transmission. The results showed that these films contain chalcopyrite structure with preferred orientation along (112) direction. The morphology, grain distribution and composition of CIASe films were studied and compared for different Al content. The optical studies revealed that the films were highly absorbing and the energy band gap calculated from transmission spectra for x=0.25, 0.5 and 0.65 were 1.2, 1.51 and 1.73 eV, respectively. The variation of Al content in the CIASe composition offered a very effective change in the optical band gap.  相似文献   
64.

Cyanine-based probe-possessing indolium iodide and indole unit were synthesized in two-step with easy available raw material: a potential probe for the cyanide ion detection. The detecting ability of the probe was investigated and confirmed by a visual and instrumental approach. A noticeable color change from orange to colorless obtained only for cyanide ions and other added ions does not impart any changes visually and through UV and Fluorescence technique. To confirm the mechanism of sensing 1H-NMR recorded. From the result, the peak belonging to N-methyl displayed an upfield shift from 4.01 δ ppm to 2.74 δ ppm due to the disappearance of indolium iodide ion and the olefin protons peaks were shifted from 7.19 to 6.17 and 8.70 to 7.20 δ ppm confirms the nucleophilic addition of cyanide ion to the probe. Test kit from filter paper prepared for the real-time monitoring cyanide ion. The prepared strip is effective in detecting cyanide ion with a visual color change.

  相似文献   
65.
Catalyst-free synthesis of the isoxazole-spirooxindole-tetrahydrothiophene hybrids is reported. Formation of 1,4-thia-Michael and intramolecular aldol reactions were observed (instead of 1,6-thia-Michael followed by vinylogous Henry reactions) in a regioselective fashion to give new isoxazole-spirooxindole-tetrahydrothiophene hybrids with excellent yields.  相似文献   
66.
This work describes a mild and robust double hydroarylation strategy for the synthesis of symmetrical /unsymmetrical diaryl- and triarylmethanes in excellent yields using Lambert salt (0.2–1.0 mol%). Despite the anticipated challenges associated with controlling selective product formation, unsymmetrical diaryl- and triarylmethanes products are obtained unprecedentedly. A highly efficient gram scale reaction has also been reported (TON for symmetrical product=475 and for unsymmetrical product=390). The synthetic utility of the methodology is demonstrated by the preparation of several unexplored diaryl- and triarylmethane-based biologically relevant molecules, such as arundine, vibrindole A, turbomycin B, and certain anti-inflammatory agents. A total synthesis of an anti-breast-cancer agent is also demonstrated. Control experiments, Hammett analysis, HRMS and GC-MS studies reveal the reaction intermediates and reaction mechanism.  相似文献   
67.
近年来,深共熔溶剂热作为一种绿色合成方法被广泛用于多种杂化功能材料的合成。在本研究中,这一合成方法被引入到多核Zr-和Zr/Ti-O纳米团簇的制备,成功获得被邻菲罗啉、苯酚等共轭配体修饰的Zr6以及Ti11Zr4团簇。此方法将为具有精准结构信息的被较多发色团包覆的纳米团簇的合成开辟新的技术路线。此外,光催化分解水产氢实验结果表明,由于具有不同的簇核环境,这两种纳米团簇表现出不同的分散性及与之相关的产氢活性。因此,该研究也为探索金属氧簇材料的结构–性能关系以及结构设计原则提供了借鉴。  相似文献   
68.
Russian Journal of General Chemistry - In the present study, we report the synthesis of 5-[4-(3-phenyl-4,5-dihydro-1H-pyrazol-5-yl)phenyl]-1H-tetrazole derivatives by the Michael addition of...  相似文献   
69.
Catalysis Surveys from Asia - Catalytic production of ethyl levulinate by alcoholysis of furfuryl alcohol with ethanol was investigated over H-mordenite supported Sn catalyst under atmospheric N2...  相似文献   
70.
A one‐step synthetic method was developed for allylation of benzamides using Ni(COD)2/RCO2H and [Ni(μ‐H2O)(OOCCMe3)2(HOOCCMe3)2]2 ( A′ ) catalytic system. Efficient, well‐defined, air and moisture‐stable Ni–pivalate complex was isolated and employed in catalytic allylation. The influence of solvent on product selectivity was also investigated.  相似文献   
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