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971.
Shouxin Cui Xiaoguang Xiao Haiquan Hu Zengtao Lv Guiqing Zhang Zizheng Gong 《Physica B: Condensed Matter》2011,406(18):3389-3391
Investigations into the structural, electronic and elastic properties of intermetallic CuZr compound had been conducted by the plane-wave pseudopotential method. The calculated lattice constant was consistent well with the experimental value. The absence of band gap and finite value of the density of states (DOS) at the Fermi level reveal the metallic behavior of CuZr crystal, and Zr 4d states give rise to the electrical conductivity. The calculated elastic constants for single crystal CuZr at zero pressure obey the cubic mechanical stability condition, which indicates that the cubic CuZr crystal is mechanical stable at zero pressure. By analyzing the ratio between the bulk and shear moduli, we conclude that CuZr crystal is ductile in nature. The present theoretical investigations might give prediction to polycrystalline CuZr system. 相似文献
972.
Zhang Sen Liu Qi Wang Wei Lv Hangbing Zuo Qingyun Wang Yan Li Yingtao Lian Wentai Long Shibing Wang Qin Liu Ming 《Applied Physics A: Materials Science & Processing》2011,105(4):1003-1009
The performances of bulk-heterojunction (BHJ) solar cells are investigated for time-dependent thermal annealing with different
morphology evolution scales, having special consideration for the diffusion and aggregation of fullerene derivative molecules
based on blends of poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM). Meaningfully, rapid formation of dot-like and needle-like crystalline PCBM structures
of a few micrometers up to 60 μm in size is obtained with thermal annealing treatment from 2 to 15 min, which dynamically
reflects a fast process of PCBM molecule and cluster aggregation. Upon ultrasonic-assisted processing and annealing treatment,
the scale of P3HT crystals is drastically increased in view of X-ray diffraction (XRD) patterns, leading to a high hole mobility.
And, the P3HT domains can be gradually converted into larger P3HT crystals approved by the decreased full width at half-maximum
in the XRD patterns. Corresponding current–voltage curves are measured in quantity and we propose a model to explain the effect
of the crystalline degree of P3HT domains and aggregation of PCBM molecules and clusters on the phase segregation, expressing
a viewpoint towards high performance of BHJ solar cells. 相似文献
973.
Varying the substrate temperature T(s) from 285 to 353 K, both the aggregation behavior of Ag atoms and the preferred structures of the atomic Ag islands on silicone oil surfaces are investigated. After deposition, the deposited Ag atoms form isolated islands with a preferred height. Our observations reveal that, as T(s) increases, the preferred island height increases from 20.0 to 33.0 nm, which results in the decrease of the Ag apparent coverage, from 9.6 ± 0.1% to 6.5 ± 0.3%. Further, the crystal structure of the Ag islands changes from amorphous to polycrystalline as the substrate temperature T(s) goes up. Subsequently a 3D aggregation mechanism of the Ag atoms on the liquid substrates is proposed. 相似文献
974.
Peng Lian Wei‐Peng Lai Hua‐Qiang Cai Shaojun Qiu Bo‐Zhou Wang Jian Lv Yong‐Qiang Xue 《International journal of quantum chemistry》2011,111(14):3571-3577
Nitrosyl cation (NO+) generating reaction HONO + H+ → NO+ + H2O has been theoretically investigated by B3LYP and high‐electron‐correlation QCISD methods with 6‐31G (d,p) basis set. The solvent effects on the geometries, reaction path properties, energies, thermodynamic, and kinetic characters in four solvents (benzene, tetrahydrofuran, acetonitrile, and water) have been calculated using self‐consistent reaction field (SCRF) approach with the polarizable continuum model (PCM). The results show that the activation energy barriers and the relative energies of the products are decreased with increase of the polarities of the solvents, and the reaction is favored in polar solvents thermodynamically and kinetically. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
975.
Benzotriazole adducts methoxycarbonylamino‐1‐(1‐benzotriazolyl)alkanes 1 were derived from the condensation of an aldehyde, benzotriazole, and methylcarbamate. The leaving tendency of methoxycarbonylamino group (MeOCONH) and benzotriazole group (Bt) was investigated by treatment of the adducts with active methylene compounds under either Lewis acid‐catalyzed or basic conditions. In the presence of SmI3, MeOCONH take priority over Bt in the leaving process, whereas in the presence of MeONa, the Bt was substituted in preference. Thus, the tunable substitution of the two leaving groups could be used for different synthetic purposes. J. Heterocyclic Chem., 00 , 00 (2011). 相似文献
976.
A Br?nsted acid-catalyzed decarboxylative redox amination involving aldehydes with 2-carboxyindoline for the synthesis of N-alkylindoles is described. The decarboxylative condensations of aldehydes with 2-carboxyindoline produce azomethine ylides in situ, which then transform into N-alkylindoles by isomerization. 相似文献
977.
Based on the cross-linking nature of BSA in the presence of glutaraldehyde (GA), the fluorescence of BSA-stabilized Au nanoclusters was effectively quenched by GA. A new method for ultrasensitive GA detection in water samples was thus developed with fluorescent BSA-stabilized Au nanoclusters. The fluorescence quenching of BSA-stabilized Au nanoclusters in the presence of GA fitted to Stern-Volmer equation. In the GA concentration range of 0.8–6 μM, a linear relationship of F0/F versus GA concentration was obtained with a limit of detection (LOD) of 0.2 μM. The relative standard deviation of 5 replicate measurements of 4 μM GA is 1.3%. This method shows good selectivity over other organics in water samples. The feasibility of the new sensor for GA in different water samples was demonstrated. 相似文献
978.
Retrospective monitoring of polycyclic aromatic hydrocarbons (PAHs) pollution levels was demonstrated by analyzing the annual rings of gingko (Gingko biloba L.) sampled from the Chengdu plain of southwest China. The samples of gingko trunk section, leaf, bark and its host soil were analyzed for PAHs by gas chromatography/mass spectrometry (GC/MS) after optimized accelerated solvent extraction (ASE). Compared to ultrasonic or soxhlet, ASE has high extraction efficiency thus meaningful contamination information contained in trunk tissue. The distribution of PAHs in gingko trunk, leaf and its host soil indicates that the main uptake pathway might be gaseous and particles-bound deposition via foliage with the exception of two-ring compounds from root, such as Nap and 2-methyl-Nap. PAHs in gingko trunk could be used to reveal the regional and historical contamination information, which is consistent with the environmental history of events (straw incineration) in Chengdu. 相似文献
979.
The interaction between mercaptoacetic acid (MA)-capped CdTe QDs, MA-capped CdTe/ZnS QDs or glutathione (GSH)-capped CdTe QDs with As(III) was studied using fluorescence spectrometry. As (III) has a high-affinity to reduced-GSH to form As(SG)3, and the emission of the GSH-capped CdTe QDs (λem. = 612 nm) is quenched effectively. Thus, a novel fluorescence spectrometric method was developed for As (III) determination by using GSH-CdTe QDs. Under optimal conditions, the quenched fluorescence intensity (F0/F) increased linearly with the concentration of As (III) ranging from 5.0 × 10−6 to 25 × 10−5 mol L−1. The limit of detection (3σ) for As (III) was found to be 2 × 10−8 mol L−1. This method is potentially useful in visual detection of As (III) under irradiation of the ultraviolet light. 相似文献
980.
Yong-Miao Shen Peng-Cheng Lv Ming-Zhu Zhang Hui-Quan Xiao Li-Ping Deng Hai-Liang Zhu Chen-Ze Qi 《Monatshefte für Chemie / Chemical Monthly》2011,31(10):521-528