检索结果-南通市图书馆

Longitudinally profiled plate leveling theory based on linear decreasing leveling scheme

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2019年第2期26卷 130-136页

作者： jian-liang sun Xing-ming Du Kai Li Yan Peng National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

An an alytical model based on linear decreasi ng leveli ng scheme was proposed to inv estigate the longitu din ally profiled plate leveling *** the variable cross-sectional thickness of longitudinally profiled plate and the dynamic reductions in leveling rolls,the reduction models of upper and lower rolls,the leveling force model and the leveling moment model were established,respectively,based on linear decreasing leveling ***,the finite element model of longitudinally profiled plate leveling process was established based on ***,the total displacements of upper and lower rolls,the leveling force and the stress distribution of longifudinally profiled plate in the leveling process were *** verify the validity of the proposed models,calculated leveling forces were compared with the measured values,and very good agreements are *** results show that linear decreasing leveling scheme is suitable for leveling longitudinally profiled plate.

关键词： Longitudi nally profiled plate Lin ear decreasing leveling Dynamic reduction Residual stress

Dynamics of rolling mill drive system considering arc tooth gear dynamic characteristics

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2019年第9期26卷 953-961页

作者： Ming Zhang Yan Peng jian-liang sun Hao-ran Li College of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

The arc tooth gear spindle (ATGS) is the key structure of the drive system of hot finishing rolling mills. To investigate the dynamic characteristics of ATGS of the drive system of hot finishing rolling mills, a dynamic mechanical model of ATGS was established. The influences of dynamic displacement and dynamic torque on dynamic load (meshing force, additional torque and friction torque) were studied during the non-steady-state operation of ATGS. On this basis, a dynamic model of rolling mill drive system was established considering the arc tooth gear dynamic characteristics. The dynamic response of the drive system was simulated and analyzed. The results showed that the nonlinear characteristics of ATGS were obvious;the meshing force (PX and PZ) could restrain the increase in dynamic displacement, which reflected the positive stiffness of ATGS;there was a coupling among the vertical, horizontal and torsional directions in the drive system model considering the dynamic characteristics of the arc tooth gear;the vibration intensity of ATGS in the horizontal direction is greater than that in the vertical direction when the self-excited torsional vibration happens;the greater the axial inclination angle was, the more complex the vibration mode was, and the lower the stability of the drive system was.

关键词： Rolling mill Drive system Arc tooth gear Coupling model Dynamic characteristics

Slab Analysis of Large Cylindrical Shell Rolling

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2014年第1期21卷 1-8页

作者： Su-wen CHEN Hong-min LIU Yan PENG jian-liang sun National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University State Key Laboratory of Metastable Materials Science and Technology Yanshan University

Considering the characteristics of large cylindrical shell rolling, such as double driving rolls, asymmetrical rolling and huge workpiece, a slab method was developed to establish the rolling force model. In this model, the non- uniform normal and shear stresses and the upper and lower surface temperatures of the workpiece were taken into ac- count. Moreover, the flow stress model, considering the dynamic recovery and dynamic recrystallization behaviors of the material, was established. The rolling pressure distribution, the rolling force, the rolling torque and the neutral points could be calculated quickly and easily by the roiling force model. The predicted results were shown to be in good agreement with the measured values, which indicated that the model can satisfy the requirement of industrial application.

关键词： large cylindrical shell rolling double driving rolls asymmetrical rolling slab method rolling force

Optically active micelles from self-assembly of MPEG-b-PMALM copolymer in water

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2009年第2期20卷 231-234页

作者： Fa Bao Zhao Zhi Lei Liu jian Ping sun liang Feng Ji Wen Hu Guangzhou Institute of Chemistry Chinese Academy of Sciences Guangzhou 510650 China

Reported here is fabrication of optically active micelles with broad range of morphologies in water, such as spheres, cylinders, and vesicles, from self-assembly of poly（ethylene glycol） monomethyl ether-b-poly- （methacryloyl-L-leucine methyl ester）（MPEG-b-PMALM） copolymer, which was prepared via atom transfer radical polymerization （ATRP） from vinyl monomer bearing chiral amino acid moieties, N-methacryloyl L-leucine methyl ester （MALM）, using bromine （Br） end-capped poly（ethylene golycol） monomethylether （MPEG-Br） as macroinitiator in the presence of CuBr/Me6TREN as catalytic system.

关键词： Block copolymers Chiroptical properties Micelles Circular dichroism (CD)

Twin pregnancy with triple parathyroid adenoma:A case report and review of literature

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2018年第11期6卷 466-471页

作者： Yu Zhang Jin-Wang Ding Ling-Ying Yu Ding-Cun Luo jian-liang sun Zhi-Kai Lei Zhi-Hua Wang Department of Oncology Affiliated Hangzhou First People's HospitalZhejiang University School of Medicine Department of Endocrinology Affiliated Hangzhou First People's HospitalZhejiang University School of Medicine Department of Anesthesiology Affiliated Hangzhou First People's HospitalZhejiang University School of Medicine Department of Ultrasound Branch Affiliated Hangzhou First People's HospitalZhejiang University School of Medicine Department of Obstetrics and Gynecology Affiliated Hangzhou First People's HospitalZhejiang University School of Medicine

Primary hyperparathyroidism(PHPT) is rare during pregnancy. A case of twin pregnancy with three simultaneous parathyroid adenomas at the same time has not been reported. Multiple parathyroid lesions are difficult to diagnose, as pregnant women who insist upon continuing a pregnancy are not able to undergo 99mTc-sestamibi scintigraphy, so cases of PHPT are easily unobserved and often can have serious consequences for the patient and the fetus. Therefore, we reported a case of a 28-year-old woman mid-pregnancy with twins, who had hypercalcemia and was eventually diagnosed with twin pregnancy with PHPT due to a triple parathyroid adenoma, had good pregnancy outcomes after undergoing surgery in mid-pregnancy. Twin pregnancy with PHPT due to a triple parathyroid adenoma, as presented in this case, is very rare and surgery in mid-pregnancy is demonstrated here as safe. Intraoperative parathormone monitoring was and remains key to a successful operation.

关键词： Primary hyperparathyroidism Pregnancy Triple parathyroid adenoma Surgery

Effects of positive psychological control intervention on sleep and psychology of officers and soldiers working at sea

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Psychiatry 2024年第10期14卷 1538-1546页

作者： Yu-Qing Liu jian-liang sun Mei Jing Guo-Xiang Liu Jie Shi Xue-Wei Zhu Fei Wang Mei-Hua Ye Department of Emergency Medicine Naval Specialty Medical CenterShanghai 200052China Department of Nursing Naval Medical UniversityShanghai 200052China Department of Disease Control and Prevention Naval Medical Center of PLANaval Medical UniversityShanghai 200052China

BACKGROUND The working environment of submarine crews is also very *** are in a closed,high-temperature,high-noise,high-vibration and narrow working and living space for a long time,and they suffer from physical discomfort caused by seasickness,which will affect the mental health of officers and *** psychologists have achieved positive results in psychological resilience training for officers and soldiers from the perspective of positive *** present,there are few reports on the correlation between psychological resilience in the field of domestic research on submarine crew psychology,and it is necessary to conduct further *** A total of 121 soldiers working in a confined space of a large ship were randomly divided into an experimental group and a control *** 50 soldiers in the experimental group were given a training course intervention,while the 71 soldiers in the control group did not receive any intervention *** Pittsburgh Sleep Quality Index,Psychological Resilience Scale,military Psycho-logical Stress Self-Assessment Questionnaire,and General Self-Efficacy Scale scores were compared before and 6 months after the *** Under the positive psychological control intervention,except for sleep efficiency(P=0.05),the difference between the remaining dimensions of the Pittsburgh Sleep Quality Index scores and the total scores of the experimental group compared with the control group was statistically significant(P<0.05);the assessment of the psychological condition showed that,in addition to the Psychological Stress Self-assessment Questionnaire for Military Personnel scores(P=0.05),the scores of the Mental Toughness Scale(Dispositional Resilience Scale Resilience II)in the experimental group,General Self-Efficacy Scale scores were statistically significant(P<0.05)compared to *** Positive psychological intervention and control can improve the sleep state and psychologica

关键词： Active psychological control intervention Officers and soldiers Sleep state Mentality Effect

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

券商声誉、制度环境与IPO公司盈余管理

管理科学学报 2017年第7期20卷 24-42页

作者：柳建华孙亮卢锐中山大学岭南学院广州510275 中山大学国际金融学院广州510275

基于成熟资本市场的研究表明,高声誉券商会抑制IPO公司的盈余管理.本文以2001-2011年处于中国制度环境下的IPO公司为样本,重新考察了券商声誉与IPO公司盈余管理之间的关系.研究发现,券商声誉越高,其所承销IPO公司的盈余管理程度也就越高... 详细信息

基于成熟资本市场的研究表明,高声誉券商会抑制IPO公司的盈余管理.本文以2001-2011年处于中国制度环境下的IPO公司为样本,重新考察了券商声誉与IPO公司盈余管理之间的关系.研究发现,券商声誉越高,其所承销IPO公司的盈余管理程度也就越高,但券商声誉与IPO公司盈余管理程度之间的正向关系只有在投资者法律保护较差的地区才显著.进一步的研究还发现,高声誉券商纵容或协助IPO公司盈余管理的重要动因在于获取更高的经济收益.尽管高声誉券商确实能够降低IPO公司的抑价率,但这是通过提高IPO公司盈余管理程度的途径来实现的.本文的结论表明,要使我国资本市场中的券商声誉机制发挥作用,还需要大力提高券商机会主义行为所面临的法律风险.

关键词：券商声誉盈余管理 IPO 投资者保护法律风险

Brain endothelial cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway in aging and neurodegeneration

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第7期20卷 2005-2007页

作者： Bryan sun Lulin Li jian Luo Palo Alto Veterans Institute for Research VA Palo Alto Health Care SystemPalo AltoCAUSA Polytrauma System of Care VA Palo Alto Health Care SystemPalo AltoCAUSA

The cyclic GMP-AMP synthase(cGAS)-stimulator of interferon genes(STING)signaling pathway has emerged as a key mediator of *** current studies primarily attribute its effects to neurons and glial cells,emerging research suggests that cGAS-STING signaling may play a critical role in cerebral vasculature,particularly in brain endothelial ***,studying the role 7of inflammation caused by the cGAS-STING pathway in brain endothelial cells could provide a more comprehensive understanding of neuroinflammatory disease and new avenues for therapeutic ***,we review the multifaceted role of global cGAS-STING signaling in various neurological and neuroinflammatory diseases and the potential contribution of cGAS-STING in brain endothelial cells.

关键词： stimulator interferon inflammation

在线全文

学校读者我要写书评

暂无评论

延安林区地栖鼠类组成及优势度分析

四川动物 2004年第1期23卷 29-32页

作者：梁健孙婷陕西师范大学生命科学学院西安710062

延安林区共有地栖鼠类 8种 ,分属 2科 6属。密度和生物量在反映不同生境鼠类作用大小方面并不一致 ,本文利用密度和生物量综合决定的重要值来表示鼠类优势度 ,分析了该区地栖鼠类组成及作用大小 ,并对不同生境中鼠类的优势度水平进行了... 详细信息

延安林区共有地栖鼠类 8种 ,分属 2科 6属。密度和生物量在反映不同生境鼠类作用大小方面并不一致 ,本文利用密度和生物量综合决定的重要值来表示鼠类优势度 ,分析了该区地栖鼠类组成及作用大小 ,并对不同生境中鼠类的优势度水平进行了比较。指出中华鼢鼠是该林区的优势种类 ,并提出了针对该鼠的造林建议。

关键词：延安林区地栖鼠类优势度生境组成