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Zinc(Ⅱ) coordination architectures based on 5-(1H-tetrazol-1-yl)-isophthalic acid:Synthesis,structures and luminescent properties

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Chinese Chemical Letters 2015年第9期26卷 1079-1084页

作者： Shu-Ming Zhang gui-xiang wang Peng Guo Yu-Huan Chen School of Chemical Engineering and Technology Hebei University of Technology

With different pyridine-analogs as auxiliary ligands,three novel Zn（Ⅱ） complexes（1-3） based on 5-（1Htetrazol-1-yl） isophthalic acid（H_2L） have been synthesized and structurally *** crystal X-ray diffraction analyses of complexes 1-3 show the presence of tetrazolyl group,as well as the coordination behavior of the auxiliary ligands as critical factors determining the structures of such Zn（Ⅱ）-carboxyIate coordination *** addition,the resulting complexes all exhibit luminescence properties in the solid state at room temperature.

关键词： Zn(Ⅱ)-carboxylate complex Pyridine-analogs Structure-tuning Luminescent properties

Synthesis of Coumarin-functionalized Calix[4]arene and Selective Recognition for L-Tryptophan

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Chinese Chemical Letters 2006年第5期17卷 575-577页

作者： Jian Quan LU Li ZHANG Ting Quan SUN gui xiang wang Ling Yan WU Hubei Key Laboratory of Bioanalytical Technique Hubei Normal University Huangshi 435002

5,11,17,23-Tetra-tert-butyl-25, 27-bis（7＇-methoxycoumarin-3＇-methyloxy）-26, 28-dihydroxycalix[4]arene was synthesized and characterized. The derivative could recognize L-tryptophan with a 1：1 complexing ratio and an apparent equilibrium constant of 111 L mol^-1 in DMF acetonitrile as solvent by UV-visible and fluorescent spectrophotometry.

关键词： Calixarene synthesis recognition L-tryptophan.

A Four-filtrated May Spectral Sequence and Its Applications

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Acta Mathematica Sinica,English Series 2008年第9期24卷 1507-1524页

作者： Xiu gui LIU xiang Jun wang School of Mathematical Sciences and LPMC,Nankai University,Tianjin 300071,P.R.China School of Mathematical Sciences and LPMC Nankai University Tianjin P. R. China

In this paper, we introduce a four-filtrated version of the May spectral sequence (MSS), from which we study the general properties of the spectral sequence and give a collapse theorem. We also give an efficient method to detect generators of May E 1-term E 1 s,t,b,* for a given (s, t, b, *). As an application, we give a method to prove the non-triviality of some compositions of the known homotopy elements in the classical Adams spectral sequence (ASS).

关键词： stable homotopy groups of spheres Adams spectral sequence May spectral sequence

Theoretical Studies on Structures and Relative Stability for Polynitrohexaazaadamantanes

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Chinese Journal of Chemical Physics 2006年第5期19卷 395-400页

作者： Xiao-juan Xu He-ming Xiao gui-xiang wang Xue-hai Ju Department of Chemistry Nanjing University of Science and Technology Nanjing 210094 China Department of Chemistry Yancheng Normal School Yancheng 224002 China

The density function theory at the B3LYP/6-31G＊ level was employed to study the structures, including the total energies （EZpE）, the geometries, the oxygen balances （OB100）, the dipole moments, of polynitrohexaazaadamantanes （PNHAAs） and the potential candidates of high energy density compounds （HEDCs）. The structural parameters of PNHAAs, such as the the maximum N-NO2 hond length （LBmax）, the least N-N Mulliken population （BN-N）, the least negative charge on the nitro group （QNO2） and OB100, were studied to predict their relative stability or sensitivity （the easiness for initiating a detonation, high sensitivity means low stability）. It was found that the same conclusion was drawn from the four parameters. With the number of nitro groups increasing, the stabilities of these compounds decrease. OB100 failed in identifying the isomers, but the EZpE energy and the dipole moment were considered to give more reliable results for the isomers.

关键词： Polynitrohexaazaadamantane Density functional theory Sensitivity Oxygen balance Mulliken population

Mapping of Defense Response Gene Homologs and Their Association with Resistance Loci in Maize

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Journal of Integrative Plant Biology 2007年第11期49卷 1580-1598页

作者： gui-xiang wang Yu Chen Jiu-Ran Zhao Lin Li Schuyler S. Korban Feng-Ge wang Jian-Sheng Li Jin-Rui Dai Ming-Liang Xu National Maize Improvement Center of China China Agncultural University Beijing 100094 China Maize Research Center Beijing Academy of Agricultural Sciences Beijing 100089 China Department of Natural Resources and Environmental Sciences University of Illinois Urbana I L 61801 USA

Defense response genes in higher plant species are involved in a variety of signal transduction pathways and biochemical reactions to counterattack invading pathogens. In this study, a total of 366 non-redundant defense response gene homologs （DRHs）, including 124 unigenes/expressed sequence tags, 226 tentative consensuses, and 16 DRH contigs have been identified by mining the Maize Genetics and Genomics and The Institute for Genomic Research maize databases using 35 essential defense response genes. Of 366 DRHs, 202 are mapped to 152 loci across ten maize chromosomes via both the genetic and in silico mapping approaches. The mapped DRHs seem to cluster together rather than be evenly distributed along the maize genome. Approximately half of these DHRs are located in regions harboring either major resistance genes or quantitative trait loci （QTL）. Therefore, this comprehensive DRH linkage map will provide reference sequences to identify either positional candidate genes for resistance genes and/or QTLs or to develop makers for fine-mapping and marker-assisted selection of resistance genes and/or QTLs.

关键词： defense response gene disease resistance maize molecular mapping.

Angiotensin II stimulates phosphorylation of 4E-binding protein 1 and p70 S6 kinase in cultured vascular smooth muscle cells

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Acta Pharmacologica Sinica 2004年第5期25卷 51-54页

作者： Na LI1, Ke-gui WU, xiang-yu wang, Liang-di XIE, Chang-sheng XU, Hua-jun wangHypertension Institute, First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China Hypertension Institute First Affiliated Hospital Fujian Medical University Fuzhou 350005

AIM: To examine the regulatory effects of angiotensin II (Ang II) on the phosphorylation of 4E-binding protein 1(4E-BP1) and p70 S6 kinase in cultured vascular smooth muscle cells (VSMC), and the contribution ofphosphatidylinositol 3-kinase (PI3K)/protein kinase B (PKB) signaling pathway in this process. METHODS: VSMCobtained from rat thoracic aortas were cultured. The phosphorylation of 4E-BP1 and p70 S6 kinase was detectedby immunoblotting. RESULTS: Ang II significantly increased the phosphorylation of 4E-BP1 and p70 S6 kinase,with the peaks occurring at, respectively, 10 min and 30 min, after stimulation with Ang II. The stimulatory effectof Ang II on 4E-BP1 and p70 S6 kinase phosphorylation was abrogated by Ang II type 1 receptor (AT1 receptor)antagonist losartan, and suppressed by PI3K inhibitor LY294002 in a concentration-dependent ***: Ang II treatment of VSMC induces the phosphorylation of 4E-BP1 and p70 S6 kinase via AT1receptor, and PI3K signaling pathway is involved in this process.

关键词： angiotensin II 4E-binding protein 1 p70 S6 kinase phosphatidylinositol 3-kinase vascular smoothmuscle

Corrosion behavior of Mg−Li alloys:A review

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Transactions of Nonferrous Metals Society of China 2021年第11期31卷 3228-3254页

作者： Xiao-chun MA Si-yuan JIN Rui-zhi WU Jia-xiu wang gui-xiang wang Boris KRIT Sergey BETSOFEN Key Laboratory of Superlight Materials&Surface Technology Ministry of EducationHarbin Engineering UniversityHarbin 150001China College of Science Heihe UniversityHeihe 164300China Moscow Aviation Institute National Research UniversityMoscow 125993Russia

It has been known that the lack of excellent corrosion resistance is the key problem restricting the wide application of Mg−Li *** on a quantity of literature about corrosion behavior of Mg−Li alloys,this review elaborates the factors affecting the corrosion behavior of Mg−Li alloys and the processing methods for improving corrosion *** corrosion characteristics of Mg−Li alloys are described ***,it is explained that the grain size,orientation,second phase,and surface film strongly influence corrosion performance,which can be tailored by alloying,plastic deformation,and heat *** in-depth discussion about the corrosion mechanisms for Mg−Li alloys was also ***,important points of improving corrosion resistance are suggested.

关键词： Mg−Li alloy corrosion behavior microstructure surface film alloying plastic deformation heat treatment

Hydrogen Promoted Decomposition of Ammonium Dinitramide:an ab initio Molecular Dynamics Study

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Chinese Journal of Chemical Physics 2018年第2期31卷 184-190,245页

作者： Ling-hua Tan Jian-hua Xu Lei Shi Xu-ran Xu gui-xiang wang Wei Jiang Nadonal Special Superfine Power Engineering Research Center Nanjing University of Science and Technology Nanjing 210094 China . School of Chemical Engineering Nanjing University of Science and Technology Nanjing 210094 China

Thermal decomposition of a famous high oxidizer arnrnoniurn dinitrarnide （ADN） under high temperatures （2000 and 3000 K） was studied by using the ab initio molecular dynamics method. Two different ternperature-dependent initial decomposition mechanisms were observed in the unirnolecular decomposition of ADN, which were the intrarnolecular hydrogen transfer and N-NO2 cleavage in N（NO2） . They were competitive at 2000 K, whereas the forrner one was predominant at 3000 K. As for the rnultimolecular decomposition of ADN, four different initial decomposition reactions that were also ternperature-dependent were observed. Apart from the aforernentioned rnechanisrns, another two new reactions were the interrnolecular hydrogen transfer and direct N-H cleavage in NH4＋. At the temperature of 2000 K, the N-NO2 cleavage competed with the rest three hydrogen-related decomposition reactions, while the direct N-H cleavage in NH4＋ was predominant at 3000 K. After the initial decomposition, it was found that the temperature increase could facilitate the decomposition of ADN, and would not change the key decomposition events. ADN decomposed into small molecules by hydrogen-prornoted simple, fast and direct chemical bonds cleavage without forrning any large intermediates that rnay impede the decomposition. The main decomposition products at 2000 and 3000 K were the same, which were NH3, NO2, NO, N2O, N2, H2O, and HNO2.

关键词： Ammonium dinitrarnide High terneprature ab initio molecular dynamics,Hydrogen transfer

Sleep Duration and Factors Related to Sleep Loss in 3-14-Year-Old Children in Beijing： A Cross-Sectional Survey

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Chinese Medical Journal 2018年第15期131卷 1799-1807页

作者： Xiao-Dan Li Jun Tai Zhi-Fei Xu gui-xiang wang Yun-Xiao Wu Jiang-Nan Du Jie Zhang Xiao-Xia Peng Xin Ni Department of Otorhinolaryngology-Head and Neck Surgery Beijing Children's Hospital Capital Medical University Beijing 100045 China Department of Respiratory Beijing Children's Hospital Capital Medical University Beijing 100045 China Beijing Key Laboratory for Pediatric Diseases of Otolaryngology Head and Neck Surgery Beijing Pediatric Research Institute Beijing Children's Hospital Capital Medical University Beijing 100045 China Center for Clinical Epidemiology and Evidence-based Medicine Beijing children's Hospital Capital Medical University Beijing 100045 China

Background： It is known that short sleep duration adversely affects children＇s behavior and physical development. This study aimed to investigate the status of sleep duration in 3-14-year-old children in Beijing and explore the related factors of sleep loss with them. Methods： In this study, a cross-sectional study of random stratified cluster sampling was conducted on 3-14-year-old children and adolescents in Beijing. According to the proportion of children in each district and school, the final cohort included a total of 11 kindergartens, 7 primary schools, and 8 junior high schools from 7 districts of Beijing. Children of sampled classes were included, and their parents were invited to fill a series of questionnaires including the simplified Chinese version of Pediatric Sleep Questionnaire, Sleep Questionnaire Scale, and Hong Kong-Children Sleep Questionnaire about the performance of the last 6 months. Results： Out of the total 11,420 questionnaires, 9198 questionnaires were valid and effective with the response rate of 80.54%. The age of the investigated children was 8.8 ± 3.8 years, including 4736 males and 4462 females. The daily sleep duration of children in Beijing was 9.7 ± 0.7 h. The prevalence of sleep loss （〈9 h/day） of children in Beijing was 11.8%. The daily sleep duration of children aged 〈6, 6 ≤ age 〈11, and ≥11 years was 9.7 ± 0.6 h, 9.6 ± 0.6 h, and 9.5 ± 0.8 h, respectively. The sleep duration reduced significantly in children aged ≥11 years as compared to younger children in Beijing which was mainly contributed by the variation tendency of sleep duration on weekdays. The multivariate logistic regression analysis identified factors associated with sleep loss （P 〈 0.05）： male （odds ratio [OR] = 1.32, 95% confidence interval [CI ]： 1.15-1.51 ）, age ≥11 years （OR = 2.37, 95% CI： 1.92-2.93）, overweight （OR = 1.34, 95% CI： 1.17-1.54）, family history of snoring （OR - 1.35, 95% CI： 1.13-1.61 ） and activities before bedtime with watching TV （OR = 1.24, 95

关键词： Child Cross-Sectional Survey Sleep Duration