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931.
Xue‐Jun Wu Xiao Huang Xiaoying Qi Hai Li Bing Li Hua Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(34):9075-9079
Two‐dimensional (2D) copper‐based ternary and quaternary semiconductors are promising building blocks for the construction of efficient solution‐processed photovoltaic devices at low cost. However, the facile synthesis of such 2D nanoplates with well‐defined shape and uniform size remains a challenge. Reported herein is a universal template‐mediated method for preparing copper‐based ternary and quaternary chalcogenide nanoplates, that is, CuInS2, CuInxGa1−xS2, and Cu2ZnSnS4, by using a pre‐synthesized CuS nanoplate as the starting template. The various synthesized nanoplates are monophasic with uniform thickness and lateral size. As a proof of concept, the Cu2ZnSnS4 nanoplates were immobilized on a Mo/glass substrate and used as semiconductor photoelectrode, thus showing stable photoelectrochemical response. The method is general and provides future opportunities for fabrication of cost‐effective photovoltaic devices based on 2D semiconductors. 相似文献
932.
933.
Determination of six polyynes in Oplopanax horridus and Oplopanax elatus using polyethylene glycol modified reversed migration microemulsion electrokinetic chromatography 下载免费PDF全文
Zhong‐mei Yang Jing Zhao Ka‐meng Lao Xiao‐jia Chen Fong Leong Chong‐Zhi Wang Chun‐Su Yuan Shao‐ping Li 《Electrophoresis》2014,35(20):2959-2964
A PEG‐modified reversed migration MEEKC method was developed for simultaneous determination of six polyynes, including oplopandiol, falcarindiol, oplopandiol acetate, (11S, 16S, 9Z)‐9,17‐octadecadiene‐12,14‐diyne‐1,11,16‐triol,1‐acetate, oplopantriol B, and oplopantriol A, in Oplopanax horridus and Oplopanax elatus. The running buffer containing 0.8% v/v ethyl acetate, 3.8% w/v SDS, 6.6% v/v n‐butanol in 20 mM phosphate buffer (pH 2.5), followed by mixing with propan‐2‐ol at 30% v/v and PEG‐1000 at 15% w/v, was applied in the analysis. The proposed method was successfully applied to determine the six polyynes in five samples of Oplopanax horridus and one of O. elatus. The result showed that the types and amounts of polyynes present were obviously different when comparing the two herbs. Besides, the developed PEG‐modified reversed MEEKC method might be suitable for the analysis of hydrophobic analytes in herbal medicines. 相似文献
934.
Genetic profile characterization and population study of 21 autosomal STR in Chinese Kazak ethnic minority group 下载免费PDF全文
Xiao‐Ye Wang Chun‐Mei Shen Wen‐Juan Liu Jiang‐Wei Yan Hong‐Dan Wang Hong‐Wei Pu Yan‐Li Wang Guang Yang Yu‐Dang Zhang Hao‐Tian Meng Hang Jing Bo‐Feng Zhu 《Electrophoresis》2014,35(4):503-510
Short tandem repeat loci have been recognized as useful tools in the routine forensic application and in recent decades, more and more new short tandem repeat (STR) loci have been constantly discovered, studied, and applied in forensic caseworks. In this study, we investigated the genetic polymorphisms of 21 STR loci in the Kazak ethnic minority as well as the genetic relationships between the Kazak ethnic minority and other populations. Allelic frequencies of 21 STR loci were obtained from 114 unrelated healthy Kazak individuals in the Ili Kazak Autonomous Prefecture, Xinjiang Uigur Autonomous Region of China. We observed a total of 159 alleles in the group with the allelic diversity values ranging from 0.0044 to 0.5088. The highest polymorphism was found at D19S433 locus and the lowest was found at D1S1627. Statistical analysis of the generated data indicated no deviation from Hardy–Weinberg equilibriums at all 21 STR loci. In order to estimate the population differentiation, allelic frequencies of all STR loci of the Kazak were compared with those of other neighboring populations using analysis of molecular variance method. Statistically significant differences were found between the studied population and other populations at 2–7 STR loci. A neighbor‐joining tree was constructed based on allelic frequencies of the 21 STR loci and phylogenetic analysis indicates that the Kazak has a close genetic relationship with the Uigur ethnic group. The present results may provide useful information for forensic sciences and population genetics studies, and can also increase our understanding of the genetic background of this group. The present findings showed that all the 21 STR loci are highly genetically polymorphic in the Kazak group, which provided valuable population genetic data for the genetic information study, forensic human individual identification, and paternity tests. 相似文献
935.
Recombination fractions between forensic STRs can be extrapolated from the International HapMap Project, but the concordance between recombination fractions predicated from genetic maps and derived from observation of STR transmissions in families is still ambiguous for autosomal STRs because of limited family studies. Therefore, the main goal of this study is to compare recombination fractions estimated by pedigree analysis with those derived from HapMap phase SNP data. Genotypes of nine autosomal STR pairs (TPOX‐D2S1772, D5S818‐CSF1PO, D7S3048‐D7S820, D8S1132‐D8S1179, TH01‐D11S2368, vWA‐D12S391, D13S325‐D13S317, D18S51‐D18S1364, and D21S11‐PentaD) from 207 two‐generation families with two to five children (the number of families with five, four, three, and two children was 2, 3, 20, and 182, respectively) were used to analyze the recombination. The linkage analysis showed that significant linkage was observed at six STR pairs (D5S818‐CSF1PO, D8S1132‐D8S1179, TH01‐D11S2368, vWA‐D12S391, D13S325‐D13S317, and D18S51‐D18S1364) with genetic distances <36.22 cM in HapMap. Their recombination fractions calculated from family data were very close to those derived from HapMap. However, three STR pairs of TPOX‐D2S1772, D7S3048‐D7S820, and D21S11‐PentaD showed no significant linkage with genetic distances from 43.38 to 91.49 cM. Our results indicate that recombination fractions extrapolated from HapMap can provide a substitute if empirical data are unavailable for the linkage STR pair with a genetic distance spanned <36.22 cM. 相似文献
936.
A simple fabrication method for tapered capillary tip and its applications in high‐speed CE and ESI‐MS 下载免费PDF全文
Yong‐Qiang Cheng Yuan Su Xiao‐Xia Fang Jian‐Zhang Pan Qun Fang 《Electrophoresis》2014,35(10):1484-1488
Fabrication of capillaries with tapered tips is an important technique that is required in many analytical chemistry areas, such as ESI‐MS, CE, electrochemical analysis, and microinjection. This paper describes a simple and effective grinding‐based fabrication method for capillaries with tapered tips. A novel grinding mode utilizing the combination of rotation and precession of an elastic capillary was developed, which significantly improved the controllability to the grinding process as well as the capillary tip shape. The capillary was fabricated by fixing it in an electric drill installed perpendicularly, and grind the capillary tip rotated around its own axis as well as the drill axis on sandpapers. Compared with conventional fabrication techniques for capillary tips, the present method is easy to control the capillary tip shape in routine laboratories without the requirement of expensive equipments or poisonous reagent (e.g. hydrofluoric acid (HF) solution). Various capillaries with different tip diameters and tip taper angles could be fabricated using the present method with good controllability and reproducibility. These capillaries were applied in high‐speed CE and ESI‐MS analysis to demonstrate the feasibility and potential of this fabrication method. 相似文献
937.
A silver-catalyzed reaction of 2-alkynylbenzaldoxime with arylsulfonyl chloride proceeds smoothly at room temperature to afford 4-tosyloxyisoquinolines in moderate to good yields. Additionally, the resulting 4-tosyloxyisoquinolines could be further elaborated through palladium-catalyzed coupling reactions leading to diverse isoquinolines. 相似文献
938.
A novel Pd-catalyzed intramolecular cyclization via tert-butyl isocyanide insertion from 2-(2-bromophenyl)-1H-indoles has been developed, which demonstrates the utility of isocyanides in C–N or C–C bond construction. Treatment of 2-(2-bromophenyl)-1H-indoles with tert-butyl isocyanide affords 6H-isoindolo[2,1-a]indol-6-ones with high efficiency. However, N-methyl or N-Boc protected 2-(2-bromophenyl)-1H-indoles gives indenoindolones in excellent yields under the same condition, which reveals that under the described situation, isocyanides insertion for the formation of C–N bonds is prior to that of C–C bonds. 相似文献
939.
Honglin Li Fengyu Liu Yi Xiao Perry J. Pellechia Mark D. Smith Xuhong Qian Guiren Wang Qian Wang 《Tetrahedron》2014
We have revisited the synthesis of a series of ICT fluorophores, which were reported to have a core structure of 8-oxo-8H-acenaphtho[1,2-b]pyrrol-9-carbonitrile. However, based on the 2D NMR and X-ray diffraction analysis, their core structure was corrected as 1-oxo-1H-phenalene-2,3-dicarbonitrile (1). Compound 1 shows a highly electron-deficient nature and can easily undergo oxidative SNArH reaction on the naphthyl ring to produce a series of novel ICT fluorophores. The regioselectivity of this substitution reaction was studied by introduction of representative nucleophiles. Moreover, due to the strong rigidity and efficient ICT nature, the obtained fluorescent dyes display very good spectroscopic properties even in an aqueous environment. 相似文献
940.
Shi-Ji Xiao Xin-Xiang Lei Bing Xia Dan-Qing Xu Hong-Ping Xiao Hong-Xi Xu Fang Chen Li-Sheng Ding Yan Zhou 《Tetrahedron letters》2014
Two novel lignans, gymnothespirolignans A (1) and B (2), possessing a rare polycyclic spiro skeleton, were isolated from the endemic plant of Gymnotheca involucrata Pei. Their structures were determined by spectroscopic evidences and the absolute configurations were confirmed by single crystal X-ray diffraction analysis. Compounds 1 and 2 showed promising antiviral activities against RSV with an IC50 value of 31.87 and 17.51 μM, respectively. 相似文献