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Chinese Chemical Letters 2002年第3期13卷 277-278页

作者： ze lin li Ji Hua HUANG Xiao Ming XIAO Yue zeNG Xia CHU Department of Chemistry Hunan Normal UniversityChangsha 410081

Potential oscillation during the electrocatalytic oxidation of methanol can be modulated by the specific adsorption of Cl- on the platinum electrode, which suppresses the electrocatalytic oxidation of methanol, and makes the cross cycle in the cyclic voltammogram become smaller and finally disappear with the increase of Cl- concentration. The method is also applicable to the electrocatalytic oxidation of other small organic molecules.

关键词： Methanol chloride ions specific adsorption potential oscillation modulation.

"Initial Potential" Effect on the Dissociative Adsorption of Methanol on A Roughened Platinum Electrode in Acidic Solution

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Chinese Chemical Letters 2001年第10期12卷 913-916页

作者： ze lin li Bin REN Chun Xing SHE Xiao Ming XIAO Zhong Qun TIAN Department of Chemistry Hunan Normal UniversityChangsha 410081 State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry Xiamen UniversityXiamen UniversityXiamen 361005

In situ Raman spectroscopic and voltammetric studies indicate that dissociative adsorption of methanol on the rough platinum electrode occurs in the hydrogen ad/desorption potential range, and the dissociative extent depends on the initial potential of the electrode before contacting methanol, in addition to the contacting time. As the dissociative product, carbon monoxide competes the site of strongly bound hydrogen preferentially, and shifts the ad/desorption potentials of weakly bound hydrogen towards more positive ones gradually with the increase of CO coverage. Whereas, formaldehyde dissociates more easily by far and completely suppresses H-adsorption. The confocal Raman spectroscopy developed on transition metals shows some intriguing advantages in investigating electrocatalytic oxidation of small organic molecules.

关键词： Methanol formaldehyde dissociative adsorption in situ Raman spectroscopy.

Two Types of Potential Oscillation During the Reduction of Dichromate on Gold Electrode in H2SO4 Solution

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Chinese Journal of Chemical Physics 2006年第3期19卷 214-218页

作者： Xiao-chun Jiang Shu Chen ze-lin li College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 China

Two different types of potential oscillations have been identified for the first time during dichromate reduction on a gold electrode in a solution of dilute sulfuric acid. One occurs before hydrogen evolution due to the formation and dissolution of passivating films of low-valence chromium oxides, and the other generates, accompanying periodic hydrogen evolution, from the coupling of electrochemical reactions with diffusive and convective mass transport. More interestingly, these two types of oscillations correspond to two crossing loops in the cyclic voltammogram （CV）. Such a relation of oscillations with crossed CVs will provide a new way to find electrochemical oscillatory systems systematically and rapidly.

关键词： Potassium dichromate Gold electrode Reduction CV criterion Potential oscillations

The Optical Variability Properties of TeV Blazars

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Research in Astronomy and Astrophysics 2024年第9期24卷 66-75页

作者： Zi-An Su Wen-Xin Yang Xiang-Tao zeng Le-Jian Ou ze-lin li Jiang-He Yang Jun-Hui Fan Department of Physics School of Physics and ElectronicsHunan Normal UniversityChangsha 410081China Center for Astrophysics Guangzhou UniversityGuangzhou 510006China Greater Bay Brand Center of the National Astronomical Data Center Guangzhou 510006China Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province Guangzhou 510006China College of Microelectronics Feicuihu Campus of Hefei University of TechnologyHefei 230601China College of Mathematics and Physics Science Hunan University of Arts and ScienceChangde 415000China

Variability is one of the typical observational properties of blazars and the spectral changes are usually associated with variability,although this kind of association is unclear *** this work,we used data from the Steward Observatory blazar monitoring program to investigate the optical variability properties including the short-term timescale,the brightness-dependent spectral property,the correlation between the the brightness variation and the polarization,and then estimate the Doppler factors based on the obtained short timescale to study the polarization property for a sample of 20 TeV *** analyses arrive at the following results:(1)The largest variation amplitude in R-band,ΔR_(M),covers a range from ΔR_(M)=0.29 mag(1ES 2344+514)to ΔR_(M)=4.66 mag(3C 279).(2)Intra-day variability was found from five sources with timescales from 0.14 day for S50716+714 to 0.98 day for PKS *** sources show spectra that are bluer when they become brighter,suggesting a common bluer-when-brighter property.(3)The plot of the polarization versus estimated Doppler factor is consistent with the Doppler factor dependent formula of polarization.(4)The largest polarization is correlated with the largest optical variation,suggesting that the high polarization and high amplitude variation are both the indicator of beaming effect.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

Prokaryotic Expression and Purification of HIV-1 Vif and hAPOBEC3G, Preparation of Polyclonal Antibodies

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Virologica Sinica 2008年第3期23卷 173-182页

作者： Lan li Yi-shu YANG ze-lin li Yi zeNG College of life Science ＆ Bio-engineering Beijing University of Technology Beijing 100124 China

To prepare HIV-1 Vif and hAPOBEC3G and to produce their antibodies, the full length gene fragment of HIV-1 vif was amplified by PCR from a plasmid of HIV-1 NL4.3 cDNA, and the APOBEC3G gene was obtained by RT-PCR from the total RNA of H9 cells. The resulting DNA construct was cloned into a prokaryotic expression vector (pET-32a). Recombinant pET-vif and pET-APOBEC3G were expressed respectively in Eserichia coli BL21 (DE3) as an insoluble protein. The vector also contained a six-histidine tag at the C-terminus for convenient purification and detection. To express and purify the HIV-1 Vif and hAPOBEC3G in *** cells, the accuracy of inserted gene and specificity of proteins were detected by the two enzyme digestion method, SDS-PAGE, and Western blotting. Rabbits were then immunized by Vif or APOBEC3G protein and serum samples were tested by indirect EliSA to determine the level of antibodies. Immunoenzyme and immunofluorescence assays were performed to identify the specificity of polyclonal antibodies. The titer of the anti-Vif antibodies was 1:204800, and that of the anti-APOBEC3G antibodies was 1:102400. Thus the antibodies could detect the antigen expression in the cells, demonstrating that fusion proteins with high purity and their corresponding polyclonal antibodies with high titer and specificity were achieved.

关键词： Human immunodeficiency virus type 1 (HIV-1) Viral infectivity factor hAPOBEC3G Protein purification Polyclonal antibody

Transforming Activity of a Novel Mutant of HPV16 E6E7 Fusion Gene

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Virologica Sinica 2011年第3期26卷 206-213页

作者： Qiang Xie Zhi-xiang Zhou ze-lin li Yi zeng （College of life Science and Bioengineering Beijing University of Technology Beijing 100124 China）

An optimized recombinant HPV16 E6E7 fusion gene (HPV16 ofE6E7) was constructed according to codon usage for mammalian cell expression, and a mutant of HPV16 ofE6E7 fusion gene (HPV16 omfE6E7) was generated by site-directed mutagenesis at L57G, C113R for the E6 protein and C24G, E26G for the E7 protein for HPV16 ofE6E7 [patent pending (CN 101100672)]. The HPV16 omfE6E7 gene constructed in this work not only lost the transformation capability to NIH 3T3 cells and tumorigenicity in SCID mice, but also maintained very good stability and antigenicity. These results suggests that the HPV16 omfE6E7 gene should undergo further study for application as a safe antigen-specific therapeutic vaccine for HPV16-associated tumors.

关键词： Human papillomavirus (HPV) E6 E7 Gene optimization Gene mutation Transformation

Impact of imipenem treatment on colonic mycobiota in rats with double-hit sepsis

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Chinese Medical Journal 2013年第10期126卷 1850-1854页

作者： GUAN Jun liUShao-ze lin Zhao-fen li Wen-fang liUXue-feng CHEN De-chang Department of Critical Care and Emergency Medicine ShanghaiChangzheng Hospital Second Military Medical University Shanghai200003 China

Background Broad-spectrum antibiotic administration promotes intestinal colonization of exogenous fungal pathogens in healthy animals and has been recognized as one of the risk factors of invasive fungal infection in clinical settings. It is unclear whether broad-spectrum antibiotic treatment would change the intestinal mycobiota without exogenous fungal challenge in the context of sepsis. Methods We established a rat model of double-hit sepsis using burn injury and endotoxin challenge. Rats with burn injury or double-hit sepsis received imipenem treatment for 3 days or 9 days, and their colon contents were sampled for selective fungal culture and isolation counts. Results Imipenem treatment promoted the overgrowth of the commensal fungus Geotrichum capitatum in rats with burn injury. Imipenem treatment also promoted colon colonization by exogenous fungi in rats with burn injury and double-hit sepsis, including Trichosporon cutaneum, Candida albicans, Candida krusei, and Candida glabrata. A longer duration of imipenem treatment had a stronger impact on colon colonization by exogenous fungi. Conclusion Imipenem treatment facilitates the overgrowth of commensal fungi and colonization by exogenous, potentially pathogenic fungi in the colons of rats with burn injury or double-hit sepsis.

关键词： sepsis, imipenem mycobiota burn, endotoxin

Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis

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World Journal of Gastroenterology 2025年第2期31卷 13-26页

作者： ze-Long Zheng Qing-Fan Zheng li-Qiang Wang Yi liu Department of Gastroenterology(Endoscopy Center) China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human *** adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut *** preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel ***,measures such as oral pro-biotics may ameliorate these adverse *** focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future.

关键词： Bowel preparation Colonoscopy Microbiota Inflammatory bowel disease Probiotics

纺织品中19种含氯苯酚的气相色谱-质谱联用测定及其迁移行为

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分析试验室 2017年第7期36卷 845-849页

作者：黄泽琳刘丽琴广州纤维产品检测研究院广州511447

建立了气相色谱-质谱联用(GC-MS)同时测定纺织品中19种残留含氯苯酚的分析方法。以棉贴衬纺织品为基底材料,采用0.1 mol/L K_2CO_3溶液作为萃取液及衍生化介质,乙酸酐乙酰化,正己烷萃取后进行GC-MS测定,采用选择离子监测进行确证,外标... 详细信息

建立了气相色谱-质谱联用(GC-MS)同时测定纺织品中19种残留含氯苯酚的分析方法。以棉贴衬纺织品为基底材料,采用0.1 mol/L K_2CO_3溶液作为萃取液及衍生化介质,乙酸酐乙酰化,正己烷萃取后进行GC-MS测定,采用选择离子监测进行确证,外标法定量。检出限为2μg/kg,线性范围为0.0004~1.0 mg/L,线性相关系数R^2大于0.999,加标回收率为88.6%~107.6%,相对标准偏差(RSDs,n=7)为1.8%~7.6%,方法可满足纺织品及其制品中19种含氯苯酚类物质的同时检测需求。研究了棉纺织品中含氯苯酚的迁移行为,表明纺织品表面涂层性质、厚度等均对此迁移行为产生一定的影响。

关键词：纺织品含氯苯酚气相色谱-质谱迁移

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中药提取物人衔草对乙型肝炎病毒的抑制作用

世界华人消化杂志 2007年第4期15卷 394-398页

作者：欧阳雁玲李泽琳曾毅北京工业大学生命科学与生物工程学院病毒药理室北京市100022

目的:观察复方制剂祛毒增宁胶囊(ZL-1)药物有效组分人衔草(JH)与HBsAg蛋白的结合情况,及其体内外抗乙型肝炎病毒的作用．方法:HepG2．2．15与不同浓度JH共培养,采用EliSA法HBsAg和HBeAg的分泌情况．建立鸭乙型肝炎病毒感染模型,以不同剂... 详细信息

目的:观察复方制剂祛毒增宁胶囊(ZL-1)药物有效组分人衔草(JH)与HBsAg蛋白的结合情况,及其体内外抗乙型肝炎病毒的作用．方法:HepG2．2．15与不同浓度JH共培养,采用EliSA法HBsAg和HBeAg的分泌情况．建立鸭乙型肝炎病毒感染模型,以不同剂量JH进行治疗,观察鸭血清乙型肝炎病毒DNA(DHBV- DNA)的变化．结果:JH作用于HepG2．2．15细胞8 d后,对细胞的半数毒性浓度(TC_(50))为1126．01 mg/L,对HBsAg和HBeAg分泌量的的半数抑制浓度(IC_(50))分别为17．52 mg/L和754．26 mg/L,对HBsAg和HBeAg的治疗指数(TC_(50)/IC_(50))分别为64．27和*** 0．8 g/kg能降低感染鸭血清DHBV-DNA水平,给药后5、10 d和停药后3 d DHBV-DNA吸光度(A)值分别为0．660±0．07, 0．632±0．03,0．663±0．05,与盐水组0．872±0．08比较,有显著性差异(P＜0．05)．结论:JH有抑制乙肝病毒的作用．

关键词：乙型肝炎病毒 HepG2.2.155M 人衔草拉米夫定