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The Optical Variability Properties of TeV Blazars

Research in Astronomy and Astrophysics 2024年第9期24卷 68-77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 Electronics Hunan Normal University Center for Astrophysics Guangzhou University Greater Bay Brand Center of the National Astronomical Data Center Astronomy Science and Technology Research Laboratory of Department of Education of Guangdong Province College of Microelectronics Feicuihu Campus of Hefei University of Technology College of Mathematics and Physics Science Hunan University of Arts and Science

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,ΔRM,covers a range fromΔRM=0.29 mag （1ES 2344+514） toΔRM=4.66 mag （3C 279）.（2） Intra-day variability was found from five sources with timescales from 0.14 day for S5 0716+714 to 0.98 day for PKS 2155–*** 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

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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

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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

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Modulation of Electrochemical Oscillations by Specific Adsorption of Cl- during the Electrooxidation of Methanol on Pt Electrode

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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.

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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

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"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.

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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

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On the Innovation,Design,Construction,and Experiments of OMEGA-Based SSPS Prototype:The Sun-Chasing Project

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Engineering 2024年第5期36卷 90-101页

作者： Baoyan Duan Yiqun Zhang Guangda Chen ze Zhao Jianwei Mi Xun li lin Yang Xi li Research Institute on Mechatronics Xidian UniversityXi’an 710071China Research Institute of Antenna Xidian UniversityXi’an 710071China

This study systematically introduces the development of the world’s first full-link and full-system ground demonstration and verification system for the OMEGA space solar power satellite(SSPS).First,the OMEGA 2.0 innovation design was ***,field-coupling theoretical models of sunlight concentration,photoelectric conversion,and transmitting antennas were established,and a systematic optimization design method was ***,a beam waveform optimization methodology considering both a high beam collection efficiency and a circular stepped beam shape was ***,a control strategy was developed to control the condenser pointing toward the sun while maintaining the transmitting antenna toward the ***,a high-efficiency heat radiator design method based on bionics and topology optimization was ***,a method for improving the rectenna array’s reception,rectification,and direct current(DC)power synthesis efficiencies is ***,high-precision measurement technology for high-accuracy beam-pointing control was ***,a smart mechanical structure was designed and ***,the developed SSPS ground demonstration and verification system has the capacity for sun tracking,a high concentration ratio,photoelectric conversion,microwave conversion and emission,microwave reception,and rectification,and thus satisfactory results were obtained.

关键词： OMEGA-SSPS Full-link and full-system Beam collection efficiency Circular stepped beam shape Smart structure Field coupling theoretical model `Beam pointing control

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Supporting IrO_(x) nanosheets on hollow TiO_(2) for highly efficient acidic water splitting

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Nano Research 2024年第8期17卷 6903-6909页

作者： Ge Yu Ruilong li Yanmin Hu Xingen lin ze lin Dongyang Wu Gongming Wang Xun Hong Center of Advanced Nanocatalysis(CAN) Department of Applied ChemistryUniversity of Science and Technology of ChinaHefei 230026China

The efficiency of proton exchange membrane water electrolysis(PEM-WE)for hydrogen production is heavily dependent on the noble metal iridium-based ***,the scarcity of iridium limits the large-scale application of *** address this issue,it is promising to select an appropriate support because it not only enhances the utilization efficiency of noble metals but also improves mass transport under high ***,we supported amorphous IrO_(x) nanosheets onto the hollow TiO_(2) sphere(denoted as IrO_(x)),which demonstrated excellent performance in acidic electrolytic water ***,the annealed IrO_(x)catalyst at 150℃in air exhibited a mass activity of 1347.5 A·gIr^(−1),which is much higher than that of commercial IrO_(2) of 12.33 A·gIr^(−1) at the overpotential of 300 mV for oxygen evolution reaction(OER).Meanwhile,the annealed IrO_(x) exhibited good stability for 600 h operating at 10 mA·cm^(−2).Moreover,when using IrO_(x) and annealed IrO_(x) catalysts for water splitting,a cell voltage as low as 1.485 V can be achieved at 10 mA·cm^(−2).The cell can continuously operate for 200 h with negligible degradation of performance.

关键词： oxygen evolution reaction hydrogen evolution reaction amorphous IrO_(x) hollow TiO_(2) proton exchange membrane water electrolysis

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The Effect of Lateral Offset Distance on the Aerodynamics and Fuel Economy of Vehicle Queues

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Fluid Dynamics & Materials Processing 2024年第1期20卷 147-163页

作者： lili Lei ze li Haichao Zhou Jing Wang Wei lin School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China

The vehicle industry is always in search of breakthrough energy-saving and emission-reduction *** recent years,vehicle intelligence has progressed considerably,and researchers are currently trying to take advantage of these *** we consider the case of many vehicles forming a queue,i.e.,vehicles traveling at a predetermined speed and distance *** the majority of existing studies on this subject have focused on the influence of the longitudinal vehicle spacing,vehicle speed,and the number of vehicles on aerodynamic drag and fuel economy,this study considers the lateral offset distance of the vehicle *** group fuel consumption savings rate is calculated and *** also demonstrated by experimental results,some aerodynamic benefits ***,the fuel consumption saving rate of the vehicle queue decreases as the lateral offset distance increases.

关键词： Vehicle platoon automotive aerodynamics horizontal offset distance fuel consumption savings rate computational fluid dynamics

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