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THEMIS statistical study on the plasma properties of high-speed flows in Earth＇s magnetotail

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Science China Earth Sciences 2016年第3期59卷 548-555页

作者： PAN Dong Xiao SUN Wei Jie SHI Quan Qi TIAN An Min YAO zhong Hua FU Sui Yan ZONG Qiu Gang zhou Xu Zhi PU Zu Yin Shandong Provincial Key Laboratory of Optical Astronomy and Solar Terrestrial Environment School of Space Science and Physics Shandong University Weihai 264209 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China School of Earth and Space Sciences Peking University Beijing 100871 China Mullard Space Science Laboratory UCL Dorking RH5 6NT UK IGPP/ESS University of California Los Angeles CA 90095-1567 USA

Using Time History of Events and Macroscale Interactions during Substorms （THEMIS） observations from 2007 to 2011 tail seasons, we study the plasma properties of high speed flows （HSFs） and background plasma sheet events （BPSs） in Earth＇s magnetotail （｜YGsM｜〈13RE, ｜ZGsM｜〈5RE, -30RE〈XrsM〈-6RE）, and their correlations with solar wind parameters. Statistical results show that the closer the HSFs and BPSs are to the Earth, the hotter they become, and the temperature increase of HSFs is larger than that of BPSs. The density and temperature ratios between HSFs and BPSs are also larger when events are closer to Earth. We also find that the best correlations between the HSFs （BPSs） density and the solar wind density occur when the solar wind density is averaged 2 （3.5） hours prior to the onset of HSFs （BPSs）. The normalized densities of both HSFs and BPSs are correlated with the interplanetary magnetic field （IMF） 0 angles （ 0 = arctan（Bz √Bx^2＋y^2 ） which are averaged 3 hours before the observation time. Further analysis indicates that both HSFs and BPSs become denser during the northward IMF period.

关键词： High-speed flow Earthward evolution Interplanetary magnetic field

Study of pyrolyzed hemin/C as non-platinum cathodic catalyst for direct methanol fuel cells

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Science China Chemistry 2010年第9期53卷 2057-2062页

作者： Qiang Wang ZhiYou zhou DeJun Chen JianLong lin FuSheng Ke GuiLiang Xu ShiGang Sun Xiamen Univ Dept Chem State Key Lab Phys Chem Solid Surfaces Coll Chem & Chem Engn Xiamen 361005 Peoples R China

Biological reduction of O2 to H2O justifies a serious look at heme as a potential O2 reduction reaction(ORR) catalyst for low temperature fuel *** this study,a novel non-platinum electrocatalyst for ORR was prepared through hemin,which is hydrochloride of heme,supported on Black Pearls 2000 carbon black(Hm-BP) pyrolyzed at 700-900℃ in Ar *** physical and electrocatalytic properties of as-prepared catalysts were characterized by TGA,XRD,XPS,TEM,rotating disk electrode(RDE) and rotating ring disk electrode(RRDE).It has found that the catalyst treated at 750℃(Hm-BP-750) exhibits the best property among the Hm-BP catalysts *** onset potential of ORR on the Hm-BP-750 at 30℃ was measured ca.0.90 V(***) in 0.1 M H2SO4,and mass current density was reached 15.3 mA mg-1 at 0.75 *** has revealed that O2 could be reduced directly to water in a 4e process between 0.9 and 0.83V,and the yield of H2O2 was 0-18% in the potential range of 0.83-0.63 *** methanol-tolerant catalyst also presents excellent stability in medium-term test of direct methanol fuel cell at 80℃.

关键词： hemin heme non-platinum catalyst oxygen reduction direct methanol fuel cell

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无标度网络度秩指数的变化范围

控制理论与应用 2006年第4期23卷 503-507,514页

作者：王林戴冠中西安理工大学自动化学院陕西西安710048 西北工业大学自动化学院陕西西安710072

实证研究表明,绝大多数复杂网络的结点的度分布服从幂律分布,该幂律分布的幂指数的绝对值(度分布指数)介于2和3之间．然而,至今尚未发现为什么度分布指数介于2和3之间的研究结果．本文证明了度分布指数大于2,从而部分回答了上述问题．为... 详细信息

实证研究表明,绝大多数复杂网络的结点的度分布服从幂律分布,该幂律分布的幂指数的绝对值(度分布指数)介于2和3之间．然而,至今尚未发现为什么度分布指数介于2和3之间的研究结果．本文证明了度分布指数大于2,从而部分回答了上述问题．为此,本文引进度秩指数,并给出了度秩指数和度分布指数之间的关系．通过对度秩指数与网络结构熵之间的关系的刻画,发现了度秩指数与网络结构熵以及网络规模之间的函数依赖关系,从而最终证明了度秩指数的临界值趋于1,并给出了仿真结果．

关键词：复杂网络无标度网络度分布度秩指数网络结构熵

Exogenous GSH protects tomatoes against salt stress by modulating photosystem Ⅱ efficiency, absorbed light allocation and H2O2-scavenging system in chloroplasts

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Journal of Integrative Agriculture 2018年第10期17卷 2257-2272页

作者： zhou Yan DIAO Ming CUI Jin-xia CHEN Xian-jun WEN Ze-lin ZHANG Jian-wei LIU Hui-ying Department of Horticulture Agricultural College Shihezi University Shihezi 832003 P.R. China Key Laboratory of Special Fruits and Vegetables Cultivation Physiology and Germplasm Resources Utilization of Xinjiang Production and Construction Crops Shihezi 832003 P.R.China

The effects of exogenous GSH（reduced glutathione）on photosynthetic characteristics,photosystem Ⅱ efficiency,absorbed light energy allocation and the H2O2-scavenging system in chloroplasts of salt-stressed tomato（Solanum lycopersicum L.）seedlings were studied using hydroponic experiments in a *** of exogenous GSH ameliorated saline-induced growth inhibition,the disturbed balance of Na＋ and Cl- ions and Na＋/K＋ ratios,and the reduction of the net photosynthetic rate（Pn）.GSH also increased the maximal photochemical efficiency of PSⅡ（Fv/Fm）,the electron transport rate（ETR）,the photochemical quenching coefficient（qP）,and the non-photochemical quenching coefficient（NPQ）.In addition,GSH application increased the photochemical quantum yield（Y（Ⅱ））and relative deviation from full balance between the photosystems（β/α-1）and decreased the PSⅡ excitation pressure（1-qP）and quantum yield of non-regulated energy dissipation（Y（NO））in leaves of salt-stressed tomatoes without BSO（L-buthionine-sulfoximine,an inhibitor of key GSH synthesis enzymeγ-glutamylcysteine synthetase）or with ***,the addition of GSH depressed the accumulation of H2O2 and malondialdehyde（MDA）,induced the redistribution of absorbed light energy in PSⅡ reaction centers,and improved the endogenous GSH content,GSH/GSSH ratio and activities of H2O2-scavenging enzymes（including superoxidase dismutase（SOD）,catalase（CAT）,peroxidase（POD）and key enzymes in the AsA-GSH cycle and Grx system）in the chloroplasts of salt-stressed plants with or without ***,GSH application alleviates inhibition of salt-induced growth and photosynthesis mainly by overcoming stomatal limitations,improving the PSⅡ efficiency,and balancing the uneven distribution of light energy to reduce the risk of ROS generation and to mediate chloroplast redox homeostasis and the antioxidant defense system to protect the chloroplasts from oxidative ***,GSH may be used as a potential tool for alleviating salt stress in to

关键词： tomato reduced glutathione NaCl stress chloroplast photosynthesis antioxidant enzyme

Offsetting the thermal expansion mismatch:a new way to high-performance solid oxide fuel cell cathodes

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Science China Chemistry 2021年第6期64卷 877-878页

作者： lin Zhuang College of Chemistry and Molecular Sciences Hubei Key Lab of Electrochemical Power SourcesWuhan UniversityWuhan 430072China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

On the cutting-edge of developing high-performance solid oxide fuel cells(SOFC),high activity and durability cathodes are required[1,2].However,the thermo-mechanical mismatch between SOFC cathode and electrolyte is the most hindering disadvantage of traditional highly active cathode materials(cobalt-containing perovskites)which usually yield higher thermal-expansion coefficient(TEC)than electrolytes[3].

关键词： expansion mismatch performance

Proliferation Inhibitory Activity of Quinones from Blaps rynchopetera Defense Secretion on Colorectal Tumor Cells

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Chinese Journal of Integrative Medicine 2023年第8期29卷 683-690页

作者： QIAN Xiao-li Meng Di LIU Heng LIU Chao-he zhou Ping YANG Yin-he WANG Jia-peng XIAO Huai DING zhong-tao Yunnan Provincial Key Laboratory of Entomological Biopharmaceutical R&D DaliYunnan Province(671003)China College of Pharmacy Dali UniversityDaliYunnan Province(671003)China Functional Molecules Analysis and Biotransformation Key Laboratory of Universities in Yunnan Province Kunming(650091)China

Objective: To explore the proliferation inhibitory effect of quinones from Blaps rynchopetera defense secretion on colorectal tumor cell lines. Methods: Human colorectal cancer cell HT-29, human colorectal adenocarcinoma cell Caco-2 and normal human colon epithelial cell CCD841 were chosen for the evaluation of inhibitory activity of the main quinones of B. rynchopetera defense secretion, including methyl p-benzoquinone(MBQ), ethyl p-benzoquinone(EBQ), and methyl hydroquinone(MHQ), through methyl thiazolyl tetrazolium assay. The tumor-related factors, cell cycles, related gene expressions and protein levels were detected by enzyme-linked immunosorbent assy, flow cytometry, RT-polymerase chain reaction and Western blot, respectively. Results: MBQ, EBQ, and MHQ could significantly inhibit the proliferation of Caco-2, with half maximal inhibitory concentration(IC50) values of 7.04±0.88, 10.92±0.32, 9.35±0.83, HT-29, with IC50values of 14.90±2.71, 20.50±6.37, 13.90±1.30, and CCD841, with IC50values of 11.40±0.68, 7.02±0.44 and 7.83±0.05 μg/mL, respectively. Tested quinones can reduce the expression of tumor-related factors tumor necrosis factor α, interleukin(IL)-10, and IL-6 in HT-29 cells, selectively promote apoptosis, and regulate the cell cycle which can reduce the proportion of cells in the G1phase and increase the proportion of the S ***, tested quinones could up-regulate mRNA and protein expression of GSK-3β and APC, while down-regulate that of β-catenin, Frizzled1, c-Myc, and CyclinD1 in the Wnt/β-catenin pathway of HT-29 ***: Quinones from B. rynchopetera defense secretion could inhibit the proliferation of colorectal tumor cells and reduce the expression of related factors, which would be functioned by regulating cell cycle, selectively promoting apoptosis, and affecting Wnt/β-catenin pathway-related mRNA and protein expressions.

关键词： Blaps rynchopetera Chinese medicine quinones anti-colorectal tumor Wnt/β-catenin pathway

Synthesis,X-Ray Structure and Characterization of a Triruthenium Cluster Complex Ru3Ⅲ（μ3-O）(μ-CH3COO)6（py）2Cl with Four Steps One-electron Redox Processes

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Chinese Chemical Letters 2003年第5期14卷 519-522页

作者： Jing lin CHEN, Gang Qiang YIN, zhong Ning CHEN* State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Fuzhou 350002 Stt. Key Lab. of Struct. Chemistry Fujian Inst. Res. Struct. of Matter Fuzhou 350002 China

The synthesis and crystal structure of oxo-centered carboxylate-bridge trinuclear ruthenium complex, Ru3O(CH3COO)6(py)2Cl (py = pyridine) (1), are reported herein. The complex 1 has been characterized by IR, cyclic voltammetry (CV), UV-Vis and X-ray crystal analysis. The complex 1 in 0.1 mol/L (n-C4H9)4NPF6-CH2Cl2 solution at room temperature shows four one- electron redox processes at E1/2 = -1.38, -1.20, -0.17 and 1.07 V vs. Ag/AgCl.

关键词： Crystal structure ruthenium carboxylate electrochemistry.

RNA interference against interleukin-5 attenuates airway inflammation and hyperresponsiveness in an asthma model

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第1期10卷 22-28页

作者： Shao-xing CHEN Feng-ying HUANG Guang-hong TANi Cai-chun WANG Yong-hao HUANG Hua WANG Song-lin zhou Fan CHEN Ying-ying lin Jun-bao LIU Hainan Provincial Key Laboratory of Tropical Medicine Hainan Medical College Haikou 571101 China Department of Digestive Diseases Affiliated Hospital of ttainan Medical College Haikou 570102 China

Interleukin-5 (IL-5) accompanies the development of airway inflammation and hyperresponsiveness through the activation of eosinophils. Therefore, interference of IL-5 expression in lung tissue seems to be an accepted approach in asthma therapy. In this study, we designed a small interfering RNA (siRNA) to inhibit the expression of IL-5. The siRNAs against IL-5 were constructed in a lentivirus expressing system, and 1.5×106 IFU (inclusion-forming unit) lentiviruses were administered intratracheally to ovalbumin (OVA)-sensitized murine asthmatic models. Our results show that lentivirus-delivered siRNA against IL-5 efficiently inhibited the IL-5 messenger ribonucleic acid (mRNA) expression and significantly attenuated the inflammation in lung tissue. Significant decrease of eosinophils and inflammatory cells were found in peripheral blood, bronchoalveolar lavage fluid (BALF), and lung tissue. In addition, significant inhibition of airway hyperresponsiveness (AHR) was found in the mice treated with siRNA against IL-5. These observations demonstrate that siRNA delivered by means of the lentivirus system is possibly an efficacious therapeutic approach for asthma.

关键词： Interleukin-5 (IL-5) Small interfering RNA (siRNA) Airway hyperresponsiveness (AHR) Allergy Lentivirus

Measurement of Temperature Change in Nonlinear Optical Materials by Using the Z-Scan Technique

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Chinese Physics Letters 2011年第8期28卷 145-148页

作者： DONG Shu-Guang YANG Jun-Yi SHUI Min YI Chuan-Xiang LI zhong-Guo SONG Ying-lin School of Physical Science and Technology Soochow UniversitySuzhou 215006 Department of Physics Harbin Institute of TechnologyHarbin 150001

Spatial and temporal changes of temperature in a novel polymer are investigated by using the Z−scan technique under ns laser pulse *** to the open aperture Z−scan experimental results,the nonlinear absorption coefficient of the polymer is *** solving the diffusion equation of heat conduction induced by optical absorption,the spatial and temporal changes in temperature are *** change in temperature drives the photo-acoustic and electromagnetic wave propagating in the polymer and induces the change in refractive index,which serves as a negative lens,and the closed aperture Z−scan shows a peak and valley *** on the numerical calculation,we achieve a good fit to the closed-aperture Z−scan curve with an optimized nonlinear refractive *** consistency attests the existence of temperature change in the solution,and the Z-scan technique is suitable to investigate this change in temperature.

关键词： temperature profile refractive