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Development of Atmosphere-controlled Tribometer and Fail-safe Analysis

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Chinese Journal of Mechanical Engineering 2012年第5期25卷 1052-1059页

作者： DUAN Haitao PEI Zhaohui WU Yong TU jiesong LI Jian Wuhan Research Institute of Materials Protection Wuhan 430030 China State Key Laboratory of Tribology Tsinghua University Beijing 100084 China

The design of existing tribometer mainly focuses on normal pressure and environmental conditions, and aims to measure the effect of load and speed on material performance. The effect of gas pressure and environmental condition on performance of materials is usually not considered. Thus, data from friction tests are not precise. In this paper, a new atmosphere tribometer is developed to study the tribological behavior of materials under severe rugged atmosphere. A fail-safe analysis is performed through reproducibility, comparability, and sensitivity tests. The tribometer allows tests to be performed in block-circle disc line contact, pin-circle disc line contact, and block-circle disc face contact configurations at controlled atmosphere and gas pressure. A self-centering plant is designed to settle the poor contact problem. A pin-on-disk test is conducted, and the test results indicate that the proposed design is efficient. A combined sealing style is introduced to control gas leaks. Compared with other sealing styles, the combined sealing is found to meet the experiment requirements best. And the reproducibility, comparability, and sensitivity tests validate the performance of the tribometer. The designed atmosphere tribometer reliably simulates the friction test under extremely harsh conditions, enhances the ability for material tribological properties test, and ensures accuracy of the tribological data.

关键词： tribometer atmosphere polymer tribological properties

Two Na^＋ and Cl^- Hyperaccumulators of the Chenopodiaceae

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Journal of Integrative Plant Biology 2005年第3期47卷 311-318页

作者： Ke-FuZHAO HaiFAN jiesong Ming-XiaSUN Bao-ZengWANG Sheng-QiangZHANG I.A.UNGAR InstituteofPlantStress ShandongNormalUniversityJinan250014China DepartmentofEnvironmentandPlantEcology OhioUniversityAthensOhio45701USA

Abstract: The authors found five sodium (Na+) and chloride (Cl-.) hyperaccumulating halophytes in the Temperate Desert of Xinjiang, China and studied two of them (Suaeda salsa (L.) Pall. and Kalidium folium (Pall.) Moq.). K. folium and S. salsa had a NaCl content of 32.1% and 29.8%, respectively, on a dry weight basis. X-ray microanalysis of the Na+ in the vacuole, apoplasts and cytoplasm of the two plants indicated a ratio of 7.3:5.6:1.0 in K. folium and 7.3:6.6:1.0 in S. salsa. These data show that K. folium and S. salsa both have a high Na+ and Cl- accumulating capacity, which is related to high activity of tonoplast H+-ATPase and H+-PPase.

关键词： apoplast Cl- cytoplasm hyperaccumulator Kalidium folium (Pall.) Moq Na+ Suaeda salsa (L.) Pall vacuole

Design of a polarization splitter for an ultra-broadband dual-core photonic crystal fiber

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Chinese Physics B 2022年第5期31卷 407-415页

作者： Yongtao Li jiesong Deng Zhen Yang Hui Zou Yuzhou Ma Academic Affairs Office Nanjing University of Posts and TelecommunicationsNanjing 210023China College of Electronic and Optical Engineering Nanjing University of Posts and TelecommunicationsNanjing 210023China State Key Laboratory of Luminescence and Applications Changchun 130033China Beijing Times Photoelectric Technology Co. LtdBeijing 100094China

A novel ultra-broadband polarization splitter based on a dual-core photonic crystal fiber(DC-PCF)is *** full-vector finite element method and coupled-mode theory are employed to investigate the characteristics of the polarization *** to the numerical results,a graphene-filled layer not only broadens the working bandwidth but also reduces the size of the polarization ***,the fluorine-doped region and the germanium-doped region can broaden the ***,the 4.78 mm long polarization splitter can achieve an extinction ratio of-98.6 d B at a wavelength of 1550 *** extinction ratio is less than-20 d B,the range of the wavelength is 1027 nm-1723 nm with a bandwidth of 696 ***,the polarization splitter can be applied to all-optical network communication systems in the infrared and near-infrared wavelength range.

关键词： photonic crystal fiber polarization splitter broadband bandwidth extinction ratio

Studies of antioxidant performance of amine additives in lubricating oil using 3D-QSAR

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Science China(Technological Sciences) 2017年第2期60卷 299-305页

作者： ZHAN ShengPeng DUAN HaiTao HUA Meng XU HaiPing SHANG HongFei JIN YongLiang JIA Dan TU jiesong LI Jian State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials ProtectionWuhan 430030China MBE Department City University of Hong KongKowloonHong KongChina Xi'an Precision Machinery Research Institute Xi'an 710075China State Key Laboratory of Tribology Tsinghua UniversityBeijing100084China

Available model of 3D-quantitative structure-activity relationship (3D-QSAR, the method of TopomerCoMFA) has been used to establish relationship between antioxidant performances of lubricating oil (trimethylolpropane trioleate, TMPTO) with 15 kinds of amine additives and its molecular structure. Correlation coefficient of the cross-validation (include internal q2 and external qpred 2 ) and conventional correlation coefficient showed the model to be both stable and good predictive. The electron-donating group and larger steric effects group are adopted at the para-position or meta-position of amido on the benzene ring, and suitably decreasing the branch chain near the para-position, these indicate that the antioxidant performance of amine additives can be enhanced. The results not only can help us understanding the rule of antioxidant performance, but also providing guidance(s) to predict antioxidant performance of existing amine additives and to design or modify new amine additives in lubricating oil.

关键词： QSAR amine additive TopomerCoMFA antioxidant performance lubrication

Stabilizing SEI by cyclic ethers toward enhanced K^(+) storage in graphite

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Journal of Energy Chemistry 2022年第8期31卷 344-350,I0010页

作者： jiesong Zhang Jian-Fang Wu Zixing Wang Ying Mo Wang Zhou Yufan Peng Bingchen He Kuikui Xiao Shi Chen Chaohe Xu Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology of Clean EnergyHunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyHunan UniversityChangsha 410082HunanChina Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao 999078China College of Aerospace Engineering Chongqing UniversityChongqing 400044China

The poor cycling stability of graphite in traditional ester electrolyte limits its applications as anodes for potassium ion batteries(KIBs).Herein,we demonstrate that the introduction of cyclic ether co-solvents into ester electrolytes can remarkably enhance the cycling stability of graphite *** graphite anode in ester electrolyte with cyclic ether could achieve a reversible capacity of 196.1 m Ah g^(-1) after 100 cycles at 0.3 C(1 C=280 m A g^(-1)),about three times higher than those in ester electrolytes with or without linear *** with the SEI formed in ester electrolytes,the addition of tetrahydrofuran promotes the generation of K_(2)CO_(3) and ethylene oxide oligomers(PEO),of which the K_(2)CO_(3) is expected to be more conductive and PEO is mechanically *** more uniform,conductive and stable solid electrolyte interphases(SEIs)on graphite in electrolytes with cyclic ethers contribute to the enhancement of the electrochemical performances of *** work provides a novel design of commercialized electrolytes to achieve high-performance anodes for KIBs,which potentially accelerates the development of KIBs.

关键词： Potassium ion batteries Solid electrolyte interphase Graphite Cyclic ether

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一类巨灾冲击模型及其债券定价

深圳大学学报（理工版） 2021年第2期38卷 208-213页

作者：张节松淮北师范大学经济与管理学院安徽淮北235000

为描述地震和台风等巨灾事件发生时间间隔的记忆效应并进行合理的风险转移,采用具有幂律性等待时间的巨灾冲击模型,即复合分数Poisson过程,刻画保险公司的承保风险,并研究巨灾保险连接债券的定价问题.运用矩匹配方法,得到累积巨灾损失... 详细信息

为描述地震和台风等巨灾事件发生时间间隔的记忆效应并进行合理的风险转移,采用具有幂律性等待时间的巨灾冲击模型,即复合分数Poisson过程,刻画保险公司的承保风险,并研究巨灾保险连接债券的定价问题.运用矩匹配方法,得到累积巨灾损失的广义Pareto型逼近分布,并在CIR(Cox-IngersollRoss)利率模型下给出债券价格公式.结合数值示例验证分布逼近的有效性,结果表明,随着记忆参数的增大,期望风险和债券价格的变化趋势相反,且二者均可能出现递增、递减或有增有减的多形态趋势,与期限水平密切相关.

关键词：概率论巨灾风险复合分数Poisson过程矩匹配方法广义Pareto分布保险连接债券

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随机巨灾索赔相依风险模型的动态最优再保险

系统工程理论与实践 2016年第2期36卷 297-307页

作者：张节松肖庆宪上海理工大学管理学院上海200093 淮北师范大学数学科学学院淮北235000

在索赔风险时变、相依条件下,建立随机巨灾的可调态再保险模型.在指明超额赔款再保险为最优分保形式的基础上,讨论并发现目标函数随自留巨灾风险水平的增大,在任意相依结构下均先减后增的变化定理,从而获得了自留向量的一般性显式表达式... 详细信息

在索赔风险时变、相依条件下,建立随机巨灾的可调态再保险模型.在指明超额赔款再保险为最优分保形式的基础上,讨论并发现目标函数随自留巨灾风险水平的增大,在任意相依结构下均先减后增的变化定理,从而获得了自留向量的一般性显式表达式.根据巨灾风险的特征,还在一类特定的相依结构下,以自留风险的期望效用和方差为优化目标,对自留向量进行了更为明确的表示并给出具体示例.结果表明,随着巨灾风险相依强度的上升,分保的满意度降低,经营稳定性减弱,对保险公司的负面影响很大.此时,为实现客观风险下的分保目标最优,常规风险的自留水平应随之增大,体现了动态再保险的优越性.

关键词：巨灾风险相依索赔动态再保险自留向量

Helicobacter pylori acquisition of metronidazole resistance by natural transformation in vitro

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World Journal of Gastroenterology 1998年第5期4卷 22-24页

作者： HUA jiesong 1, ZHENG Peng Yuan 1, Teo Keng Fong 1, Khin Mar Mar 2 and HO Bow 1

AIM To study whether Helicobacter pylori is naturally transformable. METHODS Transformation was performed in BHI broth supplemented with horse serum and yeast extract. Genomic DNA extracted from a metronidazole resistant H. pylori strain was added to H. pylori broth culture. The mixture was incubated at microaerophilic atmosphere. The DNA treated cells were plated on blood agar containing 8mg/L metronidazole to select for transformants. Sterile distilled water was used as a negative DNA control. The DNA profiles of transformants were compared with that of their parent strains by randomly amplified polymorphic DNA (RAPD) fingerprinting. RESULTS Transformation of H. pylori with DNA from a metronidazole resistant strain as a marker was demonstrated. Out of the 12 strains of H. pylori tested, 9 (75%) strains were found to be transformable. The transformation frequencies ranged from 3 4×10 -6 to 2 4×10 -4 . By RAPD, DNA fingerprints of the transformants and their parent strains showed no change in DNA profiles though transformants were all resistant to metronidazole as compared with their metronidazole sensitive parent strains. CONCLUSION Helicobacter pylori is naturally transformable which might be one of the ways that H. pylori develops resistance to metronidazole.

关键词： Helicobacter pylori metronidazole drug resistance, microbial transformation, bacterial

Research on Testing Technologies of Network System in Smart Substations

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Electricity 2012年第3期23卷 19-23页

作者： Zhang Xiaofei Wang jiesong Zhang Daoyin Zhang Zhiming Zhao Ruying Testing and Verification Center State Grid Electric Power Research Institute Nantong Shipping College

The network structures of smart substations and the characteristics of industrial Ethernet switches are *** testing technologies of network systems based on smart substations are specifically elaborated.A viewpoint is proposed that special testing policy&method of smart substation networks should be followed,so that the results can reveal the real network data exchange performance of the whole *** view ensures the safety and stability of smart substations and lays a foundation for future upgrades and expansions.

关键词： smart substation industrial Ethernet switch network testing system testing