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Seasonal differential expression of KiSS-1/GPR54 in the striped hamsters(Cricetulus barabensis)among different tissues

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Integrative Zoology 2017年第3期12卷 260-268页

作者： Laixiang xu Huiliang xuE Shenning LI jinhui xu Lei CHEN College of Life Sciences Qufu Normal UniversityQufuShandongChina

Kisspeptins and G protein coupled receptor(GPR54)play significant roles in regulating reproductive activity among seasonally reproductive animals;however,the mechanisms of KiSS-1 and GPR54 gene affecting the seasonal reproduction in striped hamster are still *** this study,real-time quantitative polymerase chain reaction was employed to examine the expression profiles of KiSS-1 and GPR54 in the hypothalamus,ovaries,testes,uterus and epididymis of striped hamsters across 4 different *** results showed that,across different seasons,the KiSS-1 expression mode of male striped hamsters and the GPR54 expression mode of female striped hamsters were consistent with the seasonal photoperiod in the ***,across different seasons,the expression profile of KiSS-1 in the testes and the GPR54 expression profile of male striped hamsters in the hypothalamus were consistent with the intensity of their seasonal reproductive *** different tissues,the expression trend for GPR54 is consistent across 4 seasons,while that for KiSS-1 is *** expression trend for GPR54 across 4 seasons is the same regardless of gender,while that for KiSS-1 is dramatically different and sex-dependent across different *** results suggest that the expressions of KiSS-1 and GPR54 in the striped hamsters were regulated by complicated mechanisms,and the regulatory mechanisms in the striped hamsters are seasonal-dependent and *** research will provide a theoretical basis for studying how KiSS-1 and GPR54 affect seasonal reproduction and the mechanisms behind their influence.

关键词： GPR54 KiSS-1 seasonal differential expression striped hamster

An approximation algorithm for k-median with priorities

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Science China(Information Sciences) 2021年第5期64卷 45-46页

作者： Zhen ZHANG Qilong FENG jinhui xu Jianxin WANG School of Computer Science and Engineering Central South University Department of Computer Science and Engineering State University of New York at Buffalo

Dear editor,Clustering is a fundamental problem in computer *** problem is to partition a given set of clients into several clusters such that clients in the same cluster are more similar to each other. In many clustering applications, the clients are different in the levels of services they require. Motivated by such applications, Ravi and Sinha [1] introduced the problem of clustering with priorities, wherein each client is associated with a priority and can only be assigned to a facility opened at the same or higher priorities.

关键词： Clustering k median approximation algorithm LP relaxtion primal-dual

Hierarchical porous carbon derived from Allium cepa for supercapacitors through direct carbonization method with the assist of calcium acetate

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Chinese Chemical Letters 2017年第12期28卷 2295-2297页

作者： jinhui xu Wenli Zhang Dianxun Hou Weimin Huang Haibo Lin College of Chemistry Jilin UniversityChangchun 130012China Department of Civii Environmentaland Architectural EngineeringUniversity of Colorado BoulderBoulder CO 80309USA Guangdong Guanghua Sci-Tech Co. Ltd.Shantou 515061China

In this paper, a direction carbonization method was used to prepare porous carbon from Allium cepa for supercapacitor applications. In this method, calcium acetate was used to assist carbonization process. Scanning electron microscope （SEM） and N2 adsorption/desorption method were used to characterize the morphology, Brunauer-Emmett-Teller （BET） specific surface area and pore size distribution of porous carbon derived from Allium cepa （onion derived porous carbon, OPC）. OPC is of hierarchical porous structure with high specific surface area and relatively high specific capacitance. OPC possesses relatively high specific surface area of 533.5 m2Jg. What＇s more, OPC possesses a specific capacitance of 133.5 Fig at scan rate of 5 mV/s.

关键词： Porous carbon Supercapacitor Allium cepa Hierarchical porous carbon Direct pyrolysis Biomass

Differentially-grown cobalt regulators cooperatively involved in the tandem catalysis for high-yield production of second amines

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Nano Research 2024年第4期17卷 2444-2450页

作者： jinhui xu Xiao Wang Ying Wang Fei Wang Lingling Zhang Wenjie Cui Shuyan Song Hongjie Zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Department of Chemistry Tsinghua UniversityBeijing 100084China

One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall *** promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem *** this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance *** comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are ***,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline ***,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring *** from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity).

关键词： tandem catalysis CeO_(2) hierarchical structure heterogeneous catalyst dual-site materials

In situ Synthesis of Ultrasmall Au Clusters on Thiol-modified CeO_(2) with Enhanced Stability and CO Oxidation Activity

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Chemical Research in Chinese Universities 2023年第6期39卷 921-927页

作者： LI Lingling xu jinhui LIANG Xi WU xueting WANG Xiao SONG Shuyan ZHANG Hongjie State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026P.R.China Department of Chemistry Tsinghua UniversityBeijing 100084P.R.

Gold(Au)nanoclusters supported on various supports have been widely used in the fields of energy and ***,the poor thermal stability of Au nanoclusters on the support interface usually leads to a reduction or even loss of catalytic ***,we used an in situ reduction method to synthesize Au nanoclusters on ceria(CeO_(2))*** this method,sulfhydryl groups were used to modify CeO_(2) nanospheres first,and then Au clusters with an average diameter of 1.5 nm were grown on the surface of ceria reduced with sodium *** presence of the Au-S-Ce structure enhances the electron transfer efficiency,making the material exhibit high CO oxidation activity at room ***,due to the strong binding energy of S and Au,the material exhibits a high stability for long time running *** strategy provides an idea for designing stable and active supported ultrasmall Au nanoclusters catalytic materials.

关键词： Au cluster Sulfhydryl Oxygen activation In situ synthesis

Distribution characteristics and influencing factors of the frequency-domain response of a vehicle–track vertical coupled system

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Journal of Modern Transportation 2016年第3期24卷 166-176页

作者： jinhui xu Biao Wang Li Wang Ping Wang MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong University

Employing theory on vehicle-track coupled dynamics, the equation of motion of a vehicle-track vertical coupled system was established by combining frequency analysis and symplectic mathematics. The frequency response of the vehicle-track vertical coupled system was calculated under the excitation of the German low-interfer- ence spectrum, and the effects of the vehicle speed, vehicle suspension parameters, and track support parameters on the frequency response of the coupled system were studied. Results show that, under the excitation of the German low- interference spectrum, the vertical vibration of the car body is mainly concentrated in the low-frequency band, while that of the bogie has a wide frequency distribution, being strong from several Hertz to dozens of Hertz. The vertical vibrations of the wheel-rail force, wheelset, and track structure mainly occur at a frequency of dozens of Hertz. In general, the vertical vibration of the vehicle-track coupled system increases with vehicle speed, and the vertical vibrations of the car body and bogie obviously shift to higher frequency. Increasing the vehicle suspension stiffness increases the low- frequency vibrations of the vehicle system and track struc- ture. With an increase in vehicle suspension damping, the low-frequency vibrations of the car body and bogie and the vibrations of the wheel-rail vertical force and track structure decrease at 50-80 Hz, while the mid-frequency and high- frequency vibrations of the car body and bogie increase. Similarly, an increase in track stiffness amplifies the vertical vibrations of the wheel-rail force and track structure, while an increase in track damping effectively reduces the vertical vibrations of the wheel-rail vertical force and track structure.

关键词： Vehicle-track coupled dynamics Frequencyresponse Distribution characteristic Influencing factors

Overview and outlook on railway track stiffness measurement

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Journal of Modern Transportation 2016年第2期24卷 89-102页

作者： Ping Wang Li Wang Rong Chen jinhui xu Jinmang xu Mingyuan Gao Key Laboratory of High-speed Railway Engineering Ministry of Education Southwest Jiaotong University School of Civil Engineering Southwest Jiaotong University

Stiffness is one of the basic performance parameters for railway track. The efficient and accurate stiffness measurement has been considered as the foundation for further development of railway engineering, and therefore has great theoretical and practical significance. Based on a summary of the connotation and measurement of track stiffness, the state of the art of measurement methods for track stiffness was analyzed systematically. The standstill measurement of track stiffness can be performed with the traditional jack-loading method, impact hammer method, FWD （falling weight deflectometer） method, and track loading vehicle method. Although these methods can be adopted in stiffness measurement for a section of railway track, they are not desirable owning to small range and low efficiency. In the recent 20 years, researchers have proposed many methods like unbalancedloading laser displacement method, deflection basin deformation rate method, and eccentricity excitation method to continuously measure track stiffness; however, these methods have drawbacks like poor accuracy, low speed, and insufficient data analysis. In this work, the merits and demerits of these methods were summarized, and optimization suggestions were presented. Based on the wave transmission mechanism and principle of vibration energy harvesting, an overall conception on continuous measurement of stiffness and long-term stiffness monitoring for special sections was proposed.

关键词： Railway·Track structure - Track stiffness Measurement · Maintenance· Vibration

Global Competency Assessment Scale for Undergraduates in the Contemporary China＇s Higher Education

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Psychology Research 2016年第6期6卷 345-360页

作者： Jian Li jinhui xu Indiana University Bloomington Bloomington U.S.A

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客货共线铁路桥上曲线参数动力分析

中南大学学报（自然科学版） 2016年第8期47卷 2891-2899页

作者：王彪胥燕军徐金辉王平西南交通大学高速铁路线路工程教育部重点实验室四川成都610031

针对200 km/h客货共线铁路桥上曲线线形平面动力设计问题,运用多刚体动力学理论及模态综合法建立列车-曲线桥耦合振动模型,研究曲线半径、缓和曲线长度及曲线外轨超高对客货共线铁路车桥耦合动力相互作用的影响。研究结果表明:曲线半径... 详细信息

针对200 km/h客货共线铁路桥上曲线线形平面动力设计问题,运用多刚体动力学理论及模态综合法建立列车-曲线桥耦合振动模型,研究曲线半径、缓和曲线长度及曲线外轨超高对客货共线铁路车桥耦合动力相互作用的影响。研究结果表明:曲线半径对车桥耦合系统的横向动力响应影响显著,车体横向加速度及桥梁跨中横向位移均随曲线半径的增大而减小,从行车安全性及旅客舒适度考虑,建议一般情况下桥上最小曲线半径不应小于5.5 km,困难条件下不应小于5.0 km;桥梁跨中横向位移随缓和曲线长度的增加略微减小,桥上曲线段缓和曲线长度可按现有规范标准进行取值;当客车或货车通过时,桥梁跨中横向位移随欠超高或过超高的增大呈线性增加,曲线外轨超高主要受货车通过时桥梁横向位移最大值控制。

关键词：客货共线车桥耦合模态综合