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Avramov–Martsinkovsky Type Exact Sequences with Tor Functors

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Acta Mathematica Sinica,English Series 2017年第11期33卷 1569-1577页

作者： chun xia ZHANG Li LIANG School of Mathematical Sciences Chongqing Normal University School of Mathematics and Physics Lanzhou Jiaotong University

For two classes of right R-modules W, X such that P W X, where P is the class of projective right R-modules, we show that there is an Avramov-Martsinkovsky type exact sequence with generalized Tate homology functor Tor^X,W, relative homology functors Tor^W and Tor^X. Many results in Iacob [Comm. Algebra, 35, 1589-1606 （2007）] and Liang [Algebr. Represent. Theory, 16, 1541-1560 （2013）] are generalized and improved.

关键词： Relative homology (generalized) Tate homology Avramov-Martsinkovsky type exact sequence

Gorenstein Projective Dimensions of Complexes

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Acta Mathematica Sinica,English Series 2011年第7期27卷 1395-1404页

作者： Zhong Kui LIU chun xia ZHANG Department of Mathematics Northwest Normal University Lanzhou 730070 P. R. China

We show that over a right coherent left perfect ring R, a complex C of left R-modules is Gorenstein projective if and only if C^m is Gorenstein projective in R-Mod for all m E Z. Basing on this we show that if R is a right coherent left perfect ring then Gpd（C） = sup{Gpd（C^m）｜m ∈ Z} where Gpd（-） denotes Gorenstein projective dimension.

关键词： Gorenstein projective complex Gorenstein projective module Gorenstein projective dimension projective preenvelope

Projected gradient trust-region method for solving nonlinear systems with convex constraints

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Applied Mathematics(A Journal of Chinese Universities) 2011年第1期26卷 57-69页

作者： JIA chun-xia ZHU De-tong Mathematics and Science College Shanghai Normal University Shanghai 200234 China Business College Shanghai Normal University Shanghai 200234 China

In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of computing trial directions by this method combining with the line search technique. Close to the solution set this method is locally Q-superlinearly convergent under an error bound assumption which is much weaker than the standard nonsingularity condition.

关键词： Nonlinear equation trust region method projected gradient local error bound.

Synthesis and electrochemical properties of 2,6-bis(6-aryl-[1,2,4]- triazolo[3,4-b][1,3,4]-thiadiazole-3-yl)pyridines

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Chinese Chemical Letters 2007年第5期18卷 505-508页

作者： chun xia Tan Ruo Fei Feng xiao xia Peng The College of Traditional Medicine of Gansu Lanzhou 730030 China Life Science ＆ Engineering College Northwest University for Nationalities Lanzhou 730030 China

By the condensation of 2,6-bis（4-amino-5-mercapto-[1,2,4]-triazoles-2）pyridine with aromatic acid in the presence of phosphorus oxychloride. Compounds of 2,6-bis（6-aryl-[1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazole-3-yl）pyridines were synthesized. Their structures were confirmed by IR, ^1H NMR spectroscopies and elemental analysis. Their electrochemical behavior and cyclic voltammogram also were be studied. The results showed that they have high ionization potentials and good affinity.

关键词： Synthesis Triazolo-thiadiazoles Electrochemical properties

Scheme for Implementing Quantum Dense Coding and Teleportation with Tripartite Entangled State in Cavity QED

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Communications in Theoretical Physics 2008年第11期50卷 1113-1116页

作者： JIA chun-xia PENG Zhao-Hui Department of Physics Hunan University of Science and Technology Xiangtan 411201 China

In this paper, we present a peculiar tripartite entangled state that is inequivalent to both the GHZ state and the W state, and then propose to implement efficient quantum information processing such as quantum dense coding and teleportation with this entangled state in cavity QED. In this scheme the atoms interact with a highly detuned cavity field with the assistance of a strong classical driven field. It does not require the transfer of quantum information between the atomic system and the cavity, and then our scheme is insensitive to both the cavity decay and the thermal field.

关键词： dense coding teleportation cavity QED

Electrochemical Study and Application on Shikonin at Poly（diallyldimethylammonium chloride） Functionalized Graphene Sheets Modified Glass Carbon Electrode

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Chemical Research in Chinese Universities 2013年第4期29卷 798-805页

作者： AN Jing LI Ji-ping CHEN Wen-xia YANG chun-xia HU Fang-di WANG chun-ming School of Pharmacy Hospital of Lanzhou University College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China

The electrochemical behaviors of shikonin at a poly（diallyldimethylammonium chloride） functionalized graphene sheets modified glass carbon electrode（PDDA-GS/GCE） have been investigated. Shikonin could exhibit a pair of well-defined redox peaks at the PDDA-GS/GCE located at 0.681 V（Epa） and 0.662 V（Epc）[vs. saturated calo- mel electrode（SCE）] in 0.1 mol/L phosphate buffer solution（pH=2.0） with a peak-to-peak separation of about 20 mV, revealing a fast electron-transfer process. Moreover, the current response was remarkably increased at PDDA- GS/GCE compared with that at the bare GCE. The electrochemical behaviors of shikonin at the modified electrode were investigated. And the results indicate that the reaction involves the transfer of two electrons, accompanied by two protons and the electrochemical process is a diffusional-controlled electrode process. The electrochemical para- meters of shikonin at the modified electrode, the electron-transfer coefficient（a）, the electron-transfer number（n） and the electrode reaction rate constant（ks） were calculated to be as 0.53, 2.18 and 3.6 s^-1, respectively. Under the optimal conditions, the peak current of differential pulse voltammetry（DPV） increased linearly with the shikonin concentra- tion in a range from 9A72×10^-8 mol/L to 3,789×10^-6 mol/L with a detection limit of 3,157× 10^-8 mol/L. The linear regression equation was Ip=O.7366c＋0.7855（R=0.9978; lp： 10-7 A, c： 10-8 mol/L）. In addition, the modified glass carbon electrode also exhibited good stability, selectivity and acceptable reproducibility that could be used for the sensitive, simple and rapid determination of shikonin in real samples. Therefore, the present work offers a new way to broaden the analytical application of graphene in pharmaceutical analysis.

关键词： Shikonin Poly(diallyldimethylammonium chloride) functionalized graphene sheets modified glass carbon electrode(PDDA-GS/GCE) Cyclic voltammetry Differential pulse voltammetry Electrochemical sensor

Experimental study of stratified lean burn characteristics on a dual injection gasoline engine

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Frontiers in Energy 2022年第6期16卷 900-915页

作者： chun xia Tingyu ZHAO Junhua FANG Lei ZHU Zhen HUANG Key laboratory of Power Machinery and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Due to increasingly stringent fuel consumption and emission regulation,improving thermal efficiency and reducing particulate matter emissions are two main issues for next generation gasoline *** burn mode could greatly reduce pumping loss and decrease the fuel consumption of gasoline engines,although the burning rate is decreased by higher diluted intake *** this study,dual injection stratified combustion mode is used to accelerate the burning rate of lean burn by increasing the fuel concentration near the spark *** effects of engine control parameters such as the excess air coefficient(Lambda),direct injection(DI)ratio,spark interval with DI,and DI timing on combustion,fuel consumption,gaseous emissions,and particulate emissions of a dual injection gasoline engine are *** is shown that the lean burn limit can be extended to Lambda=1.8 with a low compression ratio of 10,while the fuel consumption can be obviously improved at Lambda=*** exists a spark window for dual injection stratified lean burn mode,in which the spark timing has a weak effect on *** optimization of the control parameters,the brake specific fuel consumption(BSFC)decreases 9.05%more than that of original stoichiometric combustion with DI as 2 bar brake mean effective pressure(BMEP)at a 2000 r/min engine *** NO_(x) emissions before threeway catalyst(TWC)are 71.31%lower than that of the original engine while the particle number(PN)is 81.45%lower than the original *** dual injection stratified lean burn has a wide range of applications which can effectively reduce fuel consumption and particulate *** BSFC reduction rate is higher than 5%and the PN reduction rate is more than 50%with the speed lower than 2400 r/min and the load lower than 5 bar.

关键词： dual injection stratified lean burn gasoline engine particulate matter emission combustion analysis

A novel method for the determination of trace copper in cereals by dispersive liquid-liquid microextraction based on solidification of floating organic drop coupled with flame atomic absorption spectrometry

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Chinese Chemical Letters 2011年第4期22卷 473-476页

作者： chun xia Wu Qiu Hua Wu chun Wang Zhi Wang Key Laboratory of Bioinorganic Chemistry College of SciencesAgricultural University of HebeiBaoding 071001China

A novel,simple,rapid,efficient and environment-friendly method for the determination of trace copper in cereal samples was developed by using dispersive liquid-liquid microextraction based on solidification of floating organic drop（DLLME-SFO） followed by flame atomic absorption *** the DLLME-SFO,copper was complexed with 8-hydroxy quinoline and extracted into a small volume of 1-dodecanol,which is of low density,low toxicity and proper melting point near room temperature. The experimental parameters affecting the extraction efficiency were investigated and *** the optimum conditions, the calibration graph exhibited linearity over the range of 0.5—500 ng/mL with the correlation coefficient（r） of *** enrichment factor was 122 and the limit of detection was 0.1 ng/*** method was applied to the determination of copper in the complex matrix samples such as rice and millet with the recoveries for the spiked samples at 5.0 and 10.0 u,g/g falling in the range of 92.0-98.0%and the relative standard deviation of 3.9-5.7%.

关键词： Dispersive liquid-liquid microextraction based on solidification of floating organic droplet Flame atomic absorption spectrometry Copper Cereal samples

Integrative taxonomy of Leptonetela spiders (Araneae, Leptonetidae), with descriptions of 46 new species

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Zoological Research 2017年第6期38卷 321-448页

作者： chun-xia Wang Xin Xu Shu-Qiang Li Institute of Zoology Chinese Academy of Sciences Beijing 100101 China Southeast Asia Biodiversity Research Institute Chinese Academy of Sciences Yezin Nay Pyi Taw 05282 Myanmar College of Life Sciences Hunan Normal University Changsha Hunan 410006 China University of Chinese Academy of Sciences Beijing 100049 China

Extreme environments, such as subterranean habitats, are suspected to be responsible for morphologically inseparable cryptic or sibling species and can bias biodiversity assessment. A DNA barcode is a short, standardized DNA sequence used for taxonomic purposes and has the potential to lessen the challenges presented by a biotic inventory. Here, we investigate the diversity of the genus Leptonetela Kratochvil, 1978 that is endemic to karst systems in Eurasia using DNA barcoding. We analyzed 624 specimens using one mitochondrial gene fragment （COl）. The results show that DNA barcoding is an efficient and rapid species identification method in this genus. DNA barcoding gap and automatic barcode gap discovery （ABGD） analyses indicated the existence of 90 species, a result consistent with previous taxonomic hypotheses, and supported the existence of extreme male pedipalpal tibial spine and median apophysis polymorphism in Leptonetela species, with direct implications for the taxonomy of the group and its diversity. Based on the molecular and morphological evidence, we delimit and diagnose 90 Leptonetela species, including the type species Leptonetela kanellisi （Deeleman-Reinhold, 1971）. Forty-six of them are previously undescribed. The female of Leptonetela zhai Wang ＆ Li, 2011 is reported for the first time. Leptonetela tianxinensis （Tong ＆ Li, 2008） comb. nov. is transferred from the genus Leptoneta Simon, 1872; the genus Guineta Lin ＆ Li, 2010 syn. nov. is a junior synonym of Leptonetela; Leptonetela gigachela （Lin ＆ Li, 2010） comb. nov. is transferred from Guineta. The genus Sinoneta LJn ＆ Li, 2010 syn. nov. is a junior synonym of Leptonetela; Leptonetela notabilis （Lin ＆ Li, 2010） comb. nov. and Leptonetela sexdigiti （Lin ＆ Li, 2010） comb. nov. are transferred from Sinoneta; Leptonetela sanchahe Wang ＆ Li nom. nov. is proposed as a replacement name for Sinoneta palmata （Chen et a 2010） because Leptonetela palmata is preoccupied.

关键词： DNA barcoding Phylogeny Phenotype Species delineation