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Chinese Chemical Letters 2011年第9期22卷 1036-1038页

作者： xin jian song Yu Shao xing Gao Dong Key Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei University for Nationalities Enshi 445000 China Medical School Hubei University for Nationalities Enshi 445000 China

A facile microwave-assisted procedure for synthesis of novel fluorinated pyrazolo[3,4-d]pyrimidine derivatives containing 1,3,4-thiadiazole is described. This protocol presented such advantages as short reaction time, high yields, simple purification and environmentally benign procedures. Their antitumor activities were evaluated against HL-60 by an MTT assay. The preliminary results indicated that some title compounds exhibit more potent antitumor inhibitory activity than doxorubicin （DOX）.

关键词： Pyrazolo[3,4-d]pyrimidine 1,3,4-Thiadiazole Microwave-assisted synthesis Antitumor activity

Location of Caspase 3-like Protease in the Development of Sieve Element and Tracheary Element of Stem in Cucurbita moschata

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Journal of Integrative Plant Biology 2008年第12期50卷 1499-1507页

作者： Xia Hao Jie Qian Shan Xu xin song jian Zhu School of Life Science and Technology Tongji University Shanghai 200092 China

The casepase is considered to regulate the process of programmed cell death in the development of organisms. In this study, caspase 3-like protease was detected by immunohistochemistry and immunoelectron microscopy during the development of sieve element and tracheary element of stem in Cucurbita moschata Duch. Antibody with brown color （under light microscopy） and gold particles （under transmission electron microscopy） for detecting caspase 3-like protease was mainly displayed in inner phloem, external phloem and xylem in the region close to procambium. From the results it was considered that caspase 3-like protease did exist in vascular elements and played different roles during the development of sieve and tracheary elements, and different types of programmed cell death might be carried out. The caspase 3-like protease mainly participated in making cytoplasmic streaming cease and in degrading P-protein bodies; however, it rarely participated in the function for signal transferring in the developmental sieve element. However, it might induce calcium accumulation for rupturing the tonoplast in the signal of PCD in the developmental tracheary element.

关键词： caspase 3-like protease Cucurbita moschata immunoelectron microscopy P-protein bodies programmed cell death.

Synthesis and Bioactivity of Novel Fluorinated Heteroaromatic Ureas

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Chinese Chemical Letters 2006年第11期17卷 1443-1446页

作者： xin jian song Xiao Hong TAN Yan Gang WANG School of Chemical ＆ Environmental Engineering Hubei Institute for Nationalities Enshi 445000 CollegeofChemistryl Central China Normal University Wuhan 430079

In order to find new urea cytokinins, a series of novel fluorinated heteroaromatic ureas have been designed and synthesized, The crystal structure of 3g was further determined by single crystal X-ray diffraction to obtain the structural feature of this class of urea compounds. The preliminary bioassay showed that some title compounds have good cytokinin activity.

关键词： Fluorinated compound heteroaromatic urea synthesis crystal structure cytokinin activity.

A nanosilica/exfoliated graphene composite film-modified electrode for sensitive detection of methyl parathion

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Chinese Chemical Letters 2016年第9期27卷 1541-1546页

作者： Ju Fu Xiao-Hong Tan Yao-Hua Li xin-jian song Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei University for Nationalities School of Chemical and Environmental Engineering Hubei University for Nationalities

Graphene nanosheets （GS） were easily prepared through liquid-phase exfoliation of graphite powder in N,N-dimethylformamide （DMF） with the assistance of sodium citrate. Then, GS was coated onto a glassy carbon electrode （GCE） surface by drop to fabricate a GS]GCE nanointerface. Subsequently, by using tetraethylorthosilicate sol as precursor, nanosilica was electrochemically deposited onto the GS]GCE surface to produce a nanocomposite film electrode （nanosilicaJGSJGCE）. Electrochemical behaviors of methyl parathion （MP） on the nanosilica/GS/GCE surface were investigated thoroughly. It was found that the nanosilicaJGS nanocomposites can improve the redox peak currents of MP significantly due to the synergetic effect. The oxidation peak current was linearly related to MP concentration in the range from 0.0005 μmol/L to 5.6 μmol/L. The detection limit was calculated to be 0.07 nmol/L （SJN = 3）. The developed method was used to determine MP in real samples. The recoveries were in the range from 95.4% to 104.2%, demonstrating satisfactory results.

关键词： Exfoliated graphene Nanosilica Modified electrodes Methyl parathion Electrochemical sensor

Facile synthesis of novel fluorinated thieno[2,3-d]pyrimidine derivatives containing 1,3,4-thiadiazole

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Chinese Chemical Letters 2012年第5期23卷 549-552页

作者： xin jian song Zheng Chao Duan Yu Shao xing Gao Dong Key Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei University for NationalitiesEnshi 445000China Medical School Hubei University for NationalitiesEnshi 445000China

A series of novel fluorinated thieno[2,3-d]pyrimidine derivatives incorporating 1,3,4-thiadiazole were synthesized by a facile microwave-assisted procedure,including the cyclization of 2-aminothiophene-3-carbonitrile with trifluoroacetic acid,chlorination and nucleophilic substitution *** protocol offered such advantages as mild reaction conditions,short reaction time, simple puritication and good *** structures of the products were characterized by ~1H NMR,MS,elemental analysis and Xray diffraction.

关键词： Thieno[2.3-d]pyrimidine 1 3 4-Thiadiazole Trifluoromethyl Microwave-assisted synthesis

Clinical Characteristics,Diagnosis,and Therapeutics of COVID-19:A Review

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Current Medical Science 2023年第6期43卷 1066-1074页

作者： Na-na XIE Wen-cong ZHANG Jia CHEN Fang-bing TIAN jian-xin song Department of Infectious Diseases Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

The novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)that suddenly emerged at the end of December 2019 and caused coronavirus disease 2019(COVID-19)continues to afflict humanity,not only seriously affecting healthcare systems but also leading to global social and economic *** of August 2022,there were approximately 580 million confirmed cases of COVID-19 and approximately 6.4 million confirmed deaths due to this *** data are sufficient to highlight the seriousness of SARS-CoV-2 *** most patients with COVID-19 present primarily with respiratory symptoms,an increasing number of extrapulmonary systemic symptoms and manifestations have been associated with *** the outbreak of COVID-19,much has been learned about the disease and its causative ***,great effort has been aimed at developing treatments and drug interventions to treat and reduce the incidence of *** this narrative review,we provide a brief overview of the epidemiology,mechanisms,clinical manifestations,diagnosis,and therapeutics of COVID-19.

关键词： coronavirus disease 2019 severe acute respiratory syndrome coronavirus 2 mechanism clinical manifestations diagnosis therapeutics

Anycast service model and its QoS routing algorithm

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Journal of Central South University 2001年第2期8卷 135-139页

作者： WANG jian xin, CHEN song qiao, CHEN jian er (College of Information Science and Engineering, Central South University, Changsha 410083, China) College of Information Science and Engineering Central South University Changsha China

In the Internet, a group of replicated servers is commonly used in order to improve the scalability of network service. Anycast service is a new network service that can improve network load distribution and simplify certain applications. In this paper, the authors described a simple anycast service model in the Internet without significant affecting the routing and protocol processing infrastructure that was already in place, and proposed an anycast QoS routing algorithm for this model. The algorithm used randomized method to balance network load and improve its performance. Several new techniques are proposed in the algorithm, first, theminimum hops for each node are used in the algorithm, which are used as metric for computing the probability of possible out links. The metric is pre computed for each node in the network, which can simplify the network complexity and provide the routing process with useful information. Second, randomness is used at the link level and depends dynamically on the routing configuration. This provides great flexibility for the routing process, prevents the routing process from overusing certain fixed routing paths, and adequately balances the delay of the routing path. the authors assess the quality of QoS algorithm in terms of the acceptance ratio on anycast QoS requests, and the simulation results on a variety of network topologies and on various parameters show that the algorithm has good performances and can balance network load effectively.

关键词： QoS anycast service network routing randomized algorithm

Facile synthesis and antitumor activity of novel 2-trifluoromethylthieno[2,3-d]pyrimidine derivatives

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Chinese Chemical Letters 2014年第7期25卷 1006-1010页

作者： xin-jian song Ping Yang Hui Gao Yan Wang xing-Gao Dong Xiao-Hong Tan Key Laboratory of Biologic Resources Protection and Utilization of Hubei Province Hubei Minzu University College of Forestry and Horticulture Hubei Minzu University

A series of novel 2-trifluoromethylthieno[2,3-d]pyrimidine derivatives were synthesized by a facile three-step procedure that afforded advantages of mild reaction conditions, simple protocol and good yields. The structures of the final compounds were confirmed by 1R, NMR, El-MS, elemental analysis, and X-ray diffraction. Preliminary bioassay results showed that some of the analogs exhibit excellent antitumor activity against MCF-7 and HepG2, especially compounds 3a, 3b, 3e and 3h exhibited higher activity than the positive control gefitinib.

关键词： Thieno[2,3-d]pyrimidine Gewald reaction Trifluoromethyl Facile synthesis Anritumor activity

Microstructure and mechanical properties of Co-28Cr-6Mo-0.22C investment castings by current solution treatment

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China Foundry 2024年第4期21卷 369-378页

作者： Ze-yu Dan Jun Liu jian-lei Zhang Yan-hua Li Yuan-xin Deng Yun-hu Zhang Chang-jiang song Center for Advanced Solidification Technology School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Wuxi CastPro Precision Co. Ltd.Wuxi 214105JiangsuChina

This study examined the impact of current solution treatment on the microstructure and mechanical properties of the Co-28Cr-6Mo-0.22C alloy investment *** findings reveal that the current solution treatment significantly promotes the dissolution of carbides at a lower *** optimal conditions for solution treatment are determined as a solution temperature of 1,125°C and a holding time of 5.0 *** these parameters,the size and volume fraction of precipitated phases in the investment castings are measured as6.2μm and 1.1vol.%.The yield strength,ultimate tensile strength,and total elongation of the Co-28Cr-6Mo-0.22C investment castings are 535 MPa,760 MPa,and 12.6%,*** values exceed those obtained with the conventional solution treatment at 1,200°C for 4.0 *** findings suggest a phase transformation of M_(23)C_(6)→σ+C following the current solution treatment at 1,125°C for 5.0 *** comparison,the traditional solution treatment at 1,200°C for 4.0 h leads to the formation of M_(23)C_(6)and M_(6)C *** is noteworthy that the non-thermal effect of the current during the solution treatment modifies the free energy of both the matrix and precipitation *** modification lowers the phase transition temperature of the M_(23)C_(6)→σ+C reaction,thereby facilitating the dissolution of *** a result,the current solution treatment approach achieves carbide dissolution at a lower temperature and within a significantly shorter time when compared to the traditional solution treatment methods.

关键词： CoCrMo alloy investment castings current solution treatment microstructure mechanical property carbide

Grain refinement of 5A06 aluminum alloy welds caused by tungsten inert gas welding arc characteristics under Ar-He alternating gas supply conditions:a coupled method of water-cooled copper plate test/numerical simulation

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Journal of Iron and Steel Research International 2024年第3期31卷 767-777页

作者： Hong-bin Dai jian Miao Jia-xin Lin School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040HeilongjiangChina

The welding arc,as a carrier for the conversion of electrical energy to thermal energy,has a direct impact on the quality of welding by its properties and *** the tungsten inert gas(TIG)welding process under the condition of Ar-He alternating gas supply,the arc is alternately converted between Ar arc and He arc with an alternating gas supply cycle,which has obvious arc change *** FLUENT software was used to numerically simulate the characteristics of the TIG arc under the condition of alternating gas supply,and the arc temperature field,arc pressure,electric potential and current density distribution under the condition of alternating gas supply were *** with the real-time data of arc pressure measured by the water-cooled copper plate with holes,it is proved that the TIG arc has obvious dynamic characteristics under the condition of Ar-He alternating gas *** unique dynamic TIG arc acts on the 5A06 aluminum alloy weld,causing the molten pool to stir,resulting in uniform microstructure and grain refinement at the weld,and thereby improving the mechanical properties of the welded joint.

关键词： Alternating gas supply Grain refinement Numerical simulation Tungsten argon arc morphology Microstructure Mechanical property