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Transportation Safety and Environment 2024年第1期6卷 47-55页

作者： Hua Chen Chenyang Zhang Jieyu Zhang Ya Shu xinjian qi Chaozhe Jiang Sichuan FAST Fire Safety Assessment Co. LTD.Chengdu 610036SichuanChina School of Transportation and Logistics Southwest Jiaotong UniversityChengdu 611756SichuanChina Sichuan Fire Research Institute of MEM Chengdu 610036SichuanChina Shenzhen Metro Group Co. LTD.Shenzhen 518026GuangdongChina

Because of its large capacity,high efficiency and energy savings,the subway has gradually become the primary mode of transportation for citizens.A high density of passengers exists within a large-passenger-flow subway station,and the number of casualties and injuries during a fire emergency is *** this paper,Pathfinder software and on-site measured data of Pingzhou station in Shenzhen(China)were utilized to simulate a fire emergency evacuation in a large-passenger-flow subway *** Required Safe Egress Time(RSET),number of passengers and flow rates of stairs and escalators were analysed for three fire evacuation scenarios:train fire,platform fire and hall *** evacuation time of the train fire,which was 1173 s,was the longest,and 3621 occupants needed to evacuate when the train was fully *** could not complete the evacuation within 6 mins in all three fire evacuation scenarios,which does not meet the current standard requirements and *** changing the number of passengers and the number of stairs for evacuation,the flow rate capacity and evacuation time were explored,which have reference values for safety management and emergency evacuation plan optimization during peak hours of subway operation.

关键词： fire emergency evacuation large-passenger-flow subway station on-site measured data Pathfinder

MODEL OF RESEARCH CONTENT OF DISCIPLINE OF INDUSTRIAL ENGINEERING

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MODEL OF RESEARCH CONTENT OF DISCIPLINE OF INDUSTRIAL ENGINE...

双合汤对激素性股骨头缺血坏死生物力学的影响

2005年中国机械工程学会年会

作者： GU xinjian, XING Xizhe, qi Guoning, TANG Renzhong, PAN Xiaohong (Institute of Manufacturing Engineering, Zhejiang University, Hangzhou, 310027, China)

＜正＞In view of the development trend of industrial engineering （IE）, the research content of discipline of IE have been discussed with systematic viewpoint. The matrix model, hiberarchy model and integrated system... 详细信息

关键词： industrial engineering (IE) system model discipline development

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辽宁中医杂志 2017年第1期44卷 163-166,I0002页

作者：李志敏周李学段璋李新建齐振熙福建中医药大学骨伤学院福建福州350122 福建中医药大学中西结合学院福建福州350122

目的:探讨双合汤对激素性股骨头缺血坏死股骨头生物力学的影响。方法:清洁级SD大鼠40只,随机分为空白组及造模组,造模成功后,造模组分为模型组及双合汤组、血脂康组。双合汤组用双合汤以相应剂量灌胃;血脂康组用血脂康以相应剂量灌胃。... 详细信息

目的:探讨双合汤对激素性股骨头缺血坏死股骨头生物力学的影响。方法:清洁级SD大鼠40只,随机分为空白组及造模组,造模成功后,造模组分为模型组及双合汤组、血脂康组。双合汤组用双合汤以相应剂量灌胃;血脂康组用血脂康以相应剂量灌胃。空白组及模型组用生理盐水灌胃,12周后处死大鼠,取出股骨头制作成标本,观察股骨头形态变化;并取左侧股骨头做生物力学测定。比较4组间股骨头最大载荷值和最大值应变的变化。结果:1HE染色见:空白组软骨细胞及骨小梁形态正常。模型组可见大片的坏死细胞,骨小梁萎缩、稀疏。双合汤组软骨层内可见致密结缔组织增生,排列稍紊乱;骨小梁基本正常,断裂较少。血脂康组软骨细胞大量减少,骨小梁稀疏断裂,有较多的空骨陷窝。2股骨头最大值应变和最大载荷值比较:空白组>双合汤组>血脂康组>模型组。结论:双合汤增加了骨强度,改善了骨的结构力学性能,促进了坏死骨组织的修复,可用于防治激素性股骨头缺血坏死。

关键词：双合汤股骨头缺血坏死生物力学最大值应变最大载荷值

基于瞬时无功型MRAS的PMSM无速度传感器控制

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电气传动 2016年第10期46卷 13-16页

作者：韩世东张广明梅磊戚新建孙明山南京工业大学电气工程与控制科学学院江苏南京211816 中国科学院苏州生物医学工程技术研究所江苏苏州215163

研究了一种基于瞬时无功功率的MRAS永磁同步电机转速辨识系统,将PMSM瞬时无功功率作为参考模型,稳态下的无功功率作为可调模型。2个模型的输出误差,通过设计的自适应律来辨识电机转速和转子位置,利用该方案建立了永磁同步电机无速度传... 详细信息

研究了一种基于瞬时无功功率的MRAS永磁同步电机转速辨识系统,将PMSM瞬时无功功率作为参考模型,稳态下的无功功率作为可调模型。2个模型的输出误差,通过设计的自适应律来辨识电机转速和转子位置,利用该方案建立了永磁同步电机无速度传感器控制系统。理论分析和仿真结果均表明,该控制系统在转速和负载突变下均能准确跟踪转子的速度和空间位置,具有良好的鲁棒性和动、静态性能,同时降低了参数敏感性。

关键词：永磁同步电机模型参考自适应无功功率

The Promiscuous Activity of the Radical SAM Enzyme NosL toward Two Unnatural Substrates

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Chinese Journal of Chemistry 2021年第9期39卷 2417-2421页

作者： Yue Yin xinjian Ji qi Zhang Department of Chemistry Fudan UniversityShanghai 200433China

The radical S-adenosyImethionine(SAM)enzyme NosL catalyzes the conversion of L-tryptophan((-Trp,1)to 3-methyl-2-indolic acid(MIA,2),a key in termediate in the biosynthesis of the peptide an tibiotic no *** study showed that this remarkable recombination reaction starts from the cleavage of the Cα-COO^(-) bond to result in a·CO_(2)^(-) radical *** contrast to the radical SAM tyrosine lyases,NosL appears unable to cleave the Cα-Cβ bond,which is intrinsically more favorable to be cleaved than the Cα-COO^(-) *** this study,we investigate the NosL activity with tryptamine(11)and tryptophol(12),two L-Trp analogues lacking a carboxylate *** showed that NosL cleaves the C1-C2 bond of these two substrates to produce 3-methylindole(7),suggesting that the enzyme can still catalyze a β-scission when the carboxyl group of Trp is *** also showed the enzyme exhibits a promiscuous activity,initiating the reaction by abstracting hydrogen atoms from two different sites to produce two sets of products.

关键词： Biosynthesis Antibiotics Cleavage reactions Lyase Enzyme catalysis

Radical SAM-Dependent Adenosylation Involved in Bacteriohopane-polyol Biosynthesis

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Chinese Journal of Chemistry 2020年第1期38卷 39-42页

作者： Yuting Zhong xinjian Ji qi Zhang Department of Chemistry FudanUniversityShanghai 200433China

Summaryof main observation and conclusion Bacteriohopanepolyols are a group of triterpenoids that play important rolesin regulating bacterial cell membrane *** an intermediate in bacteriohopanepolyol biosynthesis,adenosylhopane production is related to a putative Fe-S protein HpnH,but the exact role of this enzyme remains *** we report characterization of HpnH as a novel radical S-adenosylmethionine(SAM)superfamily *** contrast to almost all the members in the superfamily,HpnH does not initiate the reaction by a hydrogen atom abstraction ***,it catalyzes the adenosylation of hopene via a radical addition reaction to produce adenosylhopane,representing the second example of radical SAM-dependent adenosylation involved in natural product biosynthesis.

关键词： function. process. polyol

Biochemical Characterization of an Arginine 2,3-Aminomutase with Dual Substrate Specificity

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Chinese Journal of Chemistry 2020年第9期38卷 959-962页

作者： Junfeng Zhao Wenjuan Ji xinjian Ji qi Zhang Department of Chemistry Fudan University2005 Songhu RoadShanghai 200438China

Summary of main observation and conclusion The radical S-adenosylmethionine(SAM)aminomutases represent an important pathway for the biosynthesis of p-amino *** this study,we report biochemical characterization of BlsG involved in blasticidin S biosynthesis as a radical SAM arginine 2,*** showed that BlsG acts on both£-arginine and L-lysine with comparable catalytic *** dual substrate specificity was also observed for the lysine 2,3-aminomutase from Escherichia coli(LAMec).The catalytic efficiency of LAMEc is similar to that of BlsG,but is significantly lower than that of the enzyme from Clostridium subterminale(LAMcs),which acts only on L-lysine rather than on ***,we showed that enzymes can be grouped into two major phylogenetic clades,each corresponding to a certain C3 stereochemistry of the P-amino acid *** study expands the radical SAM aminomutase members and provides insights into enzyme evolution,supporting a trade-off between substrate promiscuity and catalytic efficiency.

关键词： radical catalytic conclusion

Microstructural evolution and deformation behavior of copper alloy during rheoforging process

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Journal of Materials Science & Technology 2020年第7期42卷 17-27页

作者： Miao Cao qi Zhang Ke Huang xinjian Wang Botao Chang Lei Cai School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an710049China Zhejiang Dunan Artificial Environment Co. Ltd.Hangzhou310053China School of Science Xi’an Jiaotong UniversityXi’an710049China

A complete rheo-forming process was carried out to investigate the rheoforging process of C3771 lead brass valve,starting from the semi-solid billet preparation to rheoforging experiments and material performance *** near-spherical micro-grains with mean equivalent diameter of 56.3μm,shape factor of 0.78 were obtained when the raw C3771 lead brass were rotary swaged to a radial strain of0.22 and then heated to 895℃for 5 *** Forge 3 D software was used to analyze the temperature,strain and strain rate distribution of copper valve for obtain the reasonable process parameters during the subsequent rheoforging *** experiment results showed that near-spherical micro-grains were stretched and refined to about 35.7-43.4μm in different positions due to the dynamic recrystallization during the rheoforging *** cap thread and nut thread failure torque of the so-produced valve are also discovered to be higher than the traditionally forged copper valve with dendrite micro-grains,with an enhancement of the cap and thread failure torque of 42.2%and 28%,re s pectively.

关键词： Semi-solid Microstructural evolution Dynamic recrystallization Mechanical properties

提升末端区域电网供电能力的调控方案及稳控策略研究

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内蒙古电力技术 2024年第3期42卷 52-60页

作者：刘昭睿王凯王新建郭琪范卓内蒙古电力(集团)有限责任公司内蒙古电力调度控制分公司呼和浩特010010 内蒙古电力(集团)有限责任公司锡林郭勒超高压供电分公司内蒙古锡林浩特026000 内蒙古电力(集团)有限责任公司内蒙古电力科学研究院分公司呼和浩特010020

针对内蒙古某末端区域电网供电能力受同塔双回线路N-2故障及母线故障制约问题,开展安全稳定控制系统(以下简称稳控系统)控制策略研究。首先,基于对典型故障后末端区域电网稳定特性的仿真计算与分析,结合新能源出力、火电机组开机等对切... 详细信息

针对内蒙古某末端区域电网供电能力受同塔双回线路N-2故障及母线故障制约问题,开展安全稳定控制系统(以下简称稳控系统)控制策略研究。首先,基于对典型故障后末端区域电网稳定特性的仿真计算与分析,结合新能源出力、火电机组开机等对切负荷定值的影响,制订预控方案与稳控系统相结合的综合调度控制方案;然后,分析电解铝行业整流变压器负荷转移特性,提出可优先实切负荷量计算方法和适用于末端电网的分档阶梯切负荷原则,对末端区域电网稳控系统的控制策略进行优化。

关键词：供电能力安全稳定控制系统切负荷电压稳定暂态稳定

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垂直气电立焊接头残余应力的数值模拟

焊接技术 2024年第6期53卷 23-29页

作者：张新建祁麟瞿文军李勇胥国祥顾振强上海外高桥造船有限公司上海200137 江苏科技大学江苏镇江212100

基于热-弹-塑性理论,建立垂直气电立焊残余应力三维数值分析模型。采用均匀体热源描述焊接热输入分布。利用所建模型,模拟计算30 mm厚DH36钢对接接头焊后残余应力及其分布特征,对比分析坡口形式、焊枪摆动对焊接残余应力分布影响的规律... 详细信息

基于热-弹-塑性理论,建立垂直气电立焊残余应力三维数值分析模型。采用均匀体热源描述焊接热输入分布。利用所建模型,模拟计算30 mm厚DH36钢对接接头焊后残余应力及其分布特征,对比分析坡口形式、焊枪摆动对焊接残余应力分布影响的规律;将所测残余应力、热循环曲线结果及焊缝形状、尺寸与模拟值加以对比,验证模型的准确性。研究结果表明:对于I形坡口左右摆动且前后往复路径,焊接速度保持15 mm/s恒定,摆动频率由0 Hz增为20 Hz时,水冷侧焊缝及近缝区横向压应力及纵向压应力峰值均明显下降,等效应力谷值降低;陶瓷侧焊缝及近缝区横向压应力峰值下降明显。对于15 mm/s前后直行往复路径,对比I形坡口、V形坡口水冷侧焊缝及近缝区横、纵向压应力峰值均明显更高,高应力范围明显更大;陶瓷侧焊缝及近缝区横、纵向高应力区域更宽。

关键词： DH36钢垂直气电立焊残余应力数值模拟