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Electrochemical Determination of Epinephrine with a Pyrolytic Graphite Electrode in the Presence of Ascorbic Acid and Dopamine

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Chinese Chemical Letters 2006年第5期17卷 657-660页

作者： Xiu Hui LIU yan zhang guo Fang ZUO Xiao Quan LU College of Chemistry ＆ Chemical Engineering Northwest Normal University Lanzhou 730070

A method for determination of epinephrine（EP） in the presence of ascorbic acid （AA） and dopamine （DA） with bare pyrolytic graphite electrodes has been described for the first time. In pH 7.0 phosphate buffer solution, the linear relationship was observed between the reduction peak current of EP and its concentration over the range from 1×10^-4 to 5×10^-7 mol/L, the related coefficient is 0.9992 （N=8）.

关键词： Differential pulse voltammetry epinephrine ascorbic acid dopamine pyrolytic graphite electrodes

Molecular Basis for Stereospecific Hydrolysis of Ethyl Mandelate by Thermophilic Esterase

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Chemical Research in Chinese Universities 2011年第5期27卷 841-844页

作者： zhang guo-yan TAO Jin ZHENG Liang-yu CAO Shu-gui Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Chemistry Jilin University Changchun 130012 P. R. China

The stereospecific hydrolysis of mandelate can be effectively catalyzed by hyperthermophilic acylpeptide esterase APE 1547（Aeropyrum pernix esterase 1547）. APE 1547 used in this reaction showed a remarkable stereodi-scrimination in favour of R-mandelic acid（99% e.e.） with an enantiomeric ratio E〉200. The results of computer simulation are consistent with the experimental results. It can be inferred that the R-substrate adopted a binding mode productive of the reaction due to the formation of the hydrogen bond at the active site of APE 1547.

关键词： Hyperthermophilic acylpeptide esterase Biocatalyst Stereospecific hydrolysis Mandelic acid Computer simulation

Novel preparation of NaA/carbon nanocomposite thin films with high permeance for CO_2/CH_4 separation

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Chinese Chemical Letters 2007年第4期18卷 455-457页

作者： Zhi Hui Zhou Jian Hua yang Li Feng Chang yan zhang Wei guo Sun Jin Qu Wang State Key Laboratory of Fine Chemicals Institute of Adsorption and Inorganic Membrane Dalian University of Technology Dalian 116012 PR China

Novel NaA/carbon nanocomposite thin films were successfully prepared on a porous α-Al2O3 substrate by incorporating nanosized NaA zeolite into novolak-type phenolic resin. The prepared films were characterized by XRD, SEM and single gas permeation tests. The NaA zeolite/carbon nanocomposite thin films exhibited that the ideal separation factor of CO2/CH4 was 28.4 and the carbon dioxide flux was 3.39 ×10^-7 mol/（Pa m^2 s） at room temperature and under a pressure difference of 100 kPa, which was two orders of magnitude higher than that of pure carbon membrane prepared at the same procedures and conditions as those of composite films. From the SEM images, the films were continuous and highly intergrown. Compared with carbon membranes, the thickness of nanocomposite films was drastically decreased, which was helpful to reduce the diffusion resistance and increase the flux of gas permeance.

关键词： Nanocomposite Thin films High performance Gas separation

Establishment of Ecotilling for Discovery of DNA Polymorphisms in Brassica rapa Natural Population

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Agricultural Sciences in China 2005年第9期4卷 654-659页

作者： WU Jian SUN Ri-fei zhang yan-guo WANG Xiao-wu Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China Graduate School Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

Ecotilling is a new approach based on enzyme-mediated heteroduplex cleavage to discover DNA polymorphisms in natural population. We used mung bean nuclease（MBN） instead of routinely used CELI to cleave single base pair mismatches in heteroduplex DNA templates. Nested set of primers were designed to amplify targeted region to avoid the influence of the variation in quality and quantity of the genomic DNA. To reduce the costs in fluorescently labeled primers, we added M13 adapter to 5＇end of gene specific primers to make IRD dye labeled M13 forward and reverse primers possibly universal for different genes. A Brassica rapa ZIP gene homologue was subjected to the analysis to practise the feasibility of the method in polymorphisms detection. Our experiment showed this method is efficient in discovering DNA polymorphisms in Brassica rapa natural population.

关键词： Ecotilling MBN DNA polymorphism

Identification of QTLs Related to Bolting in Brassica rapa ssp. pekinensis (syn. Brassica campestris ssp. pekinensis)

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Agricultural Sciences in China 2006年第4期5卷 265-271页

作者： zhang Xiao-wei WU Jian ZHAO Jian-jun SONG Xiao-fei LI Ying zhang yan-guo XU Dong-hui SUN Ri-fei YUAN Yu-xiang XIE Cong-hua WANG Xiao-wu College of Horticulture and Forestry Science Huazhong Agricultural University Wuhan 430070 P.R.China Institute of Vegetables and Flowers. Chinese Academy of Agriculture Sciences Beijing 100081 P.R.China Institute of Biotechnology Henan Academy of Agricultural Sciences Zhengzhou 450002 P.R.China Life Science College Hebei Agricultural University Baoding 071101 P.R.China

A genetic linkage map of Brassica rapa ssp. pekinensis was constructed with 186 AFLP （amplified fragment length polymorphism） markers by using a doubled-haploid （DH） population with 183 individuals. The individuals were derived from F1 which was developed by crossing a bolting resistant DH line Y-177-12 and an easy bolting DH line Y195-93a. AFLPs were generated by the use of restriction enzymes EcoR Ⅰ and Mse Ⅰ . The segregation of each marker and linkage was analyzed by using JoinMap version 3.0. Mapped markers were aligned in ten linkage groups which covered 887.8 cM with an average marker interval of 4.47 cM. Markers showing skewed segregation ratio were clustered in six LGs. Quantitative trait loci （QTL） were mapped for bolting resistance by using MAPQTL 4.0 package. Four QTLs explaining from 7.0 to 9.4% of the total variation were detected, all of them increase bolting resistance. These mapped QTLs could be used to develop a marker assisted selection programme for bolting resistance breeding.

关键词： bolting QTL linkage map Chinese cabbage

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大口径新型顶管力学行为现场试验研究

岩土工程学报 2017年第10期39卷 1842-1850页

作者：张耀闫治国朱合华同济大学土木工程防灾国家重点实验室上海200092 同济大学土木工程学院地下建筑与工程系上海200092

通过对新型预应力钢筒混凝土顶管(JPCCP)开展现场试验,得到了在施工荷载、水土压力等三维荷载作用下顶管各部位的应变时程响应;同时也获得了顶进过程中管–土接触应力时程变化。根据对数据的分析,得出预应力钢筒混凝土顶管具有较大的纵... 详细信息

通过对新型预应力钢筒混凝土顶管(JPCCP)开展现场试验,得到了在施工荷载、水土压力等三维荷载作用下顶管各部位的应变时程响应;同时也获得了顶进过程中管–土接触应力时程变化。根据对数据的分析,得出预应力钢筒混凝土顶管具有较大的纵向抗压刚度,而纵向抗拉刚度不足。由于预应力的效应,内层混凝土与中间层混凝土能够承受较大的环向拉应力。通过对管节的纵向受力分析,计算出管–土平均摩阻力随顶进距离的变化规律,结合施工记录得出平均摩阻力随顶进距离先增大后减小,最小值为1.27 k Pa;同时,施工顶进间隔越短,平均摩阻力越小。此外,实测结果表明,管–土接触应力对管节运动较为敏感,最大瞬时值可达500 k Pa;施工结束后,接触应力沿管周分布并不对称或均匀,但与实测管节环向应变分布对应。

关键词：预应力钢筒混凝土顶管管–土接触应力管–土平均摩阻力应变时程响应

Pre-mental foramen mandibulotomy for resecting tumors of tongue base and parapharyngeal space

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Chinese Medical Journal 2005年第21期118卷 1803-1807页

作者： YU Guang-yan zhang Lei guo Chuan-bin HUANG Min-xian MAO Chi PENG Xin Department of Oral and Maxillofacial Surgery Peking University School and Hospital of Stomatology Beijing 100081 China

Background Resection of tumors arising from the tongue base and the parapharyngeal space is difficult for exposure and manipulation because of their obscure location. The aim of this study was to evaluate the surgical approach of the pre-mental foramen mandibulotomy for resecting the tumors of tongue base and parapharyngeal space. Methods Fifty-one patients with tumors of tongue base and parapharyngeal space were treated using the mandibulotomy approach on the pre-mental foramen. In the present study, this technique was described in detail. The patients were followed up for three months to six years with a mean of 26 months. Results The tumors of tongue base and parapharyngeal space could be exposed clearly and be resected radically by surgical approach of pre-mental foramen mandibulotomy. The surgical complications were reduced. Conclusions Compared to other surgical approaches, such as lateral mandibulotomy, midline mandibulotomy, the suprahyoid parapharyngeal approach, and paramedian mandibulotomy, we found that the pre-mental foramen mandibulotomy is the ideal choice for resecting the tumors of tongue base and parapharyngeal space.

关键词： tumor of the tongue base parapharyngeal tumor pre-mental foramen mandibulotomy surgical approach

Vitro Culture and Immunohistochemical Identification of Astrocytes of Infantile Optic Nerve

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眼科学报 2000年第3期16卷 203-207页

作者： Jianliang Zheng, Yuqing Lan, Jie zhang, yan guo, yan LuoZhongshan Ophthalmic Center, Sun Yat-sen University of Medical Sciences andNational Ophthalmological Laboratories, Ministry of Public Health, China, Guangzhou 510060, China Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences and National Ophthalmological Laboratories Ministry of Public Health China.

Objective: To culture astrocytes of optic nerve and to establish the cell lines for further study of healing process after optic nerve ***: Optic nerve astrocytes of infantile and adults with sudden death were cultured by tissue inoculation or tissue digestion with 0. 25% Trypsin and 0. 06% EDTA. The second and fourth passage cells were stained with HE and and- GFAP, S-100 protein, Vi-mentin, and CD34 ***: The trypsinized astrocytes of infantile optic nerve reached confluence in 7 days, but the astrocytes of adults weren't successfully cultured. The cultured cells were in polygonal shape with processes; the cytoplasm was abundant and pink; the cells had light-blue nuclei. These cells were positive in GFAP, S-100 protein and vimentin staining, and negative in CD34 ***: The results showed that astrocytes of infantile optic nerve can be successfully cultured and trypsinization is a better method than tissue inoculation. The culture of infantile astrocytes is

关键词：视神经星形细胞体外培养免疫组化

系统整理马克思主义在中国早期传播文献的学术价值——兼评《马克思主义在中国早期传播著作选集(1920—1927)》

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湖北大学学报（哲学社会科学版） 2019年第2期46卷 12-14,172页

作者：张艳国江西师范大学中国社会转型研究中心江西南昌330022

2019年是五四运动一百周年纪念,是中国人开始接触马克思主义理论(1899年)的一百二十周年纪念。在中国马克思主义早期传播史上,五四运动具有关键意义。五四时期,具体来说是十月革命之后,'马克思主义在中国真正有意义上的传播'[1]。五四... 详细信息

2019年是五四运动一百周年纪念,是中国人开始接触马克思主义理论(1899年)的一百二十周年纪念。在中国马克思主义早期传播史上,五四运动具有关键意义。五四时期,具体来说是十月革命之后,'马克思主义在中国真正有意义上的传播'[1]。五四时期是近代中西文化发生剧烈冲撞、交融、重构.

关键词：马克思主义早期传播学术价值