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Journal of Iron and Steel Research International 2021年第9期28卷 1125-1132页

作者： Hong-gang Zhong Xiang-ru Chen yan-jie liu Zhi-qiang Wei Hai-feng Yu Qi-jie Zhai Center for Advanced Solidification Technology Shanghai UniversityShanghai200444China Shanghai Institute of Materials Genome Shanghai200444China Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai200431China

The influences of superheat and cooling intensity on macrostructure and macrosegregation of one new kind duplex stainless steel(DSS)were *** simulation equipment was applied to prepare samples,which could reproduce the industrial processes of DSS manufactured by a vertical continuous slab *** and macrosegregation were analyzed using the digital single lens reflex and laser-induced breakdown spectroscope(LIBSOPA-200),*** percentage of both chill zone and center equiaxed zone increases with the superheat decreasing,while that of the columnar zone *** is only equiaxed grain existing as the superheat is 10 and 20℃.The lower the superheat is,the coarser the gain size *** cooling intensity in mold could remarkably decrease the chill zone length and refine the grains in chill zone and center equiaxed *** influences of cooling intensity on macrosegregation are greater than those of *** macrosegregation of Si,Mn and Cr is slightly dependent on superheat,while that of Cu,Mo and Ni changes greatly with superheat increasing.

关键词： Continuous casting Solidification Thermal simulation Duplex stainless steel Macrosegregation

Effects of pulse magneto-oscillation on GCr15 bearing steel continuous casting billet

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Journal of Iron and Steel Research International 2022年第1期29卷 144-150页

作者： yan-jie liu Guo-dong Xu Ying-chun Wang Hong-gang Zhong Li-juan Li Biao Wang Qi-jie Zhai Materials Genome Institute Shanghai UniversityShanghai 200444China Center for Advanced Solidification Technology Shanghai UniversityShanghai 200444China Research Institute China Baowu Steel Group CorporationShanghai 200431China Steel Plant China Baowu Steel Group CorporationShanghai 200431China

Pulse magneto-oscillation(PMO)added during solidification could affect the solidification structure and macrosegregation.A modified thermal simulation equipment was applied to prepare GCr15 bearing steel continuous casting billets with different PMO peak ***,metallographic analysis,component analysis and numerical simulation were adopted to study the influence of PMO peak current and its *** sample with 150 K_(I)A PMO peak current treatment has little difference with the samples without PMO treatment on solidification structure and *** the peak currents are 250 and 350 K_(I)A,the columnar zone increases and macrosegregation *** 450 K_(I)A peak current is selected,the equiaxed grain ratio is enlarged,and the dendritic grains are refined,and the macrosegregation of C,Cr,Si and Mn is decreased *** analyzing,different convections induced by PMO with various peak currents are the key factor to change the solidification structure and macrosegregation.

关键词： Bearing steel Numerical simulation Thermal simulation Pulse magneto-oscillation

Lower gastrointestinal bleeding:Role of 64-row computed tomographic angiography in diagnosis and therapeutic planning

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World Journal of Gastroenterology 2015年第13期21卷 4030-4037页

作者： Jian-Zhuang Ren Meng-Fan Zhang Ai-Mei Rong Xiang-jie Fang Kai Zhang Guo-Hao Huang Peng-Fei Chen Zhao-yang Wang Xu-Hua Duan Xin-Wei Han yan-jie liu Department of Interventional Radiology the First Affiliated Hospital of Zhengzhou University Department of General Surgery the First Affiliated Hospital of Zhengzhou University

AIM: To determine the value of computed tomographic angiography(CTA) for diagnosis and therapeutic planning in lower gastrointestinal(GI) ***: Sixty-three consecutive patients with acute lower GI bleeding underwent CTA before endovascular or surgical treatment. CTA was used to determine whether the lower GI bleeding was suitable for endovascular treatment, surgical resection, or conservative treatment in each patient. Treatment planning with CTA was compared with actual treatment decisions or endovascular or surgical treatment that had been carried out in each patient based on CTA ***: 64-row CTA detected active extravasation of contrast material in 57 patients and six patients had no demonstrable active bleeding, resulting in an accuracy of 90.5% in the detection of acute GI bleeding(57 of 63). In three of the six patients with no demonstrable active bleeding, active lower GI bleeding recurred within one week after CTA, and angiography revealed acute bleeding. The overall location-based accuracy, sensitivity, specificity, positive predictive value(PPV) and negative predictive value(NPV) for the detection of GI bleeding by 64-row CTA were 98.8%(249 of 252), 95.0%(57 of 60), 100%(192 of 192), 100%(57 of 57), and 98.5%(192 of 195), respectively. Treatment planning was correctly established on the basis of 64-row CTA with an accuracy, sensitivity, specificity, PPV and NPV of 98.4%(248 of 252), 93.3%(56 of 60), 100%(192 of 192), 100%(56 of 56), and 97.5%(192 of 196), respectively, in a location-based evaluation. CONCLUSION: 64-row CTA is safe and effective in making decisions regarding treatment, without performing digital subtraction angiography or surgery, in the majority of patients with lower GI bleeding.

关键词： Gastrointestinal bleeding Digital subtractionangio

Correlation between Sex and Prognosis of Acute Aortic Dissection in the Chinese Population

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Chinese Medical Journal 2018年第12期131卷 1430-1435页

作者： yan-jie liu Xiao-Zeng Wang Ya Wang Rui-Xia He Lin yang Quan-Min Jing Hai-Wei liu Department of Cardiology Institute of Cardiovascular Research General Hospital of Shenyang Military Region Shenyang Liaoning 110016 China

Background： The prevalence, presentation, management, and prognosis of coronary heart disease differ according to sex. Greater understanding on the differences between men and women with acute aortic dissection （AAD） is needed. We aimed to investigate whether sex disparities are found in patients with AAD, and to study sex differences in complications, mortality in-hospital, and tong-term. Methods： We included 884 patients enrolled in our institute between June 2002 and May 2016. Considering psychosocial factors, treatments, and the outcomes in men versus those in women with AAD, we explored the association of sex with psychosocial characteristics and mortality risk. For categorical variables, significant differences between groups were assessed with the Chi-square test or Fisher＇s exact test, and continuous parameters were assessed with Student＇s t-test. Univariate and stratified survival statistics were computed using Kaplan-Meier analysis. Results： A total of 884 patients （76.1% male, mean age 51.4 ± 11.8 years） were inchidcd in this study. There were fewer current smokers in female compared with male （ 17.5% vs. 67.2%,χ^2= 160.06, P〈 0.05）. The percentage of men who reported regular alcohol consumption was significantly higher than that in women （40.6% vs. 3.8%, χ^2== 100.18, P 〈 0.05）. About 6.2% （55 of 884） of patients with AAD died before vascular or endovascular surgery was performed, 34.4% （304 of 884） of patients underwent surgical procedures, and 52.7% （466 of 884） and 12.8% （113 of 884） of patients received endovascular treatment and medication, Postoperative mortality similar （6.0% vs. 5.6%, respectively, χ^2= 0.03, P = 0.91） between men and women. Follow-up was completed in 653 of 829 patients （78.8%）. Adjustment for age, history of coronary disease, hypertension, smoking and drinking, Type A and use of beta-blocker, angiotensin II receptor blockers, angiotensin converting enzyme （ACE） inhibitor, calcium-channel blockers and statins by multivariate log

关键词： Aortic Dissection: Prognosis Sex

Safety and Necessity of Antiplatelet Therapy on Patients Underwent Endovascular Aortic Repair with Both Stanford Type B Aortic Dissection and Coronary Heart Disease

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Chinese Medical Journal 2017年第19期130卷 2321-2325页

作者： Rui-Xia He Lei Zhang Tie-Nan Zhou Wen-jie Yuan yan-jie liu Wen-Xia Fu Quan-Min Jing Hai-Wei liu Xiao-Zeng Wang Department of Cardiology General Hospital of Shenyang Military Region Shenyang Liaoning 110016 China

Background： Acute aortic dissection is known as the most dangerous aortic disease, with management and prognosis determined as the disruption of the medial layer provoked by intramural bleeding. The objective of this study was to evaluate the safety and necessity of antiplatelet therapy on patients with Stanford Type B aortic dissection （TBAD） who underwent endovascular aortic repair （EVAR）. Methods： The present study retrospectively analyzed 388 patients with TBAD who underwent EVAR and coronary angiography. The primary outcomes were hemorrhage, death, endoleak, recurrent dissection, myocardial infarction, and cerebral infarction in patients with and without aspirin antiplatelet therapy at 1 month and 12 months. Results： Of those 388 patients, 139 （35.8%） patients were treated with aspirin and 249 （64.2%） patients were not treated with aspirin. Patients in the aspirin group were elderly （57.0 ± 10.3 years vs. 52.5 ± 11.9 years, respectively, χ2 = 3.812, P 〈 0.001） and had more hypertension （92.1% vs. 83.9%, respectively, χ2 = 5.191, P = 0.023） and diabetes （7.2% vs. 2.8%, respectively, χ2 = 4.090, P = 0.043） than in the no-aspirin group. Twelve patients （aspirin group vs. no-aspirin group; 3.6% vs. 2.8%, respectively, χ2 = 0.184, P = 0.668） died at 1-month follow-up, while the number was 18 （4.6% vs. 5.0%, respectively, χ2 = 0.027, P = 0.870） at 12-month follow-up. Hemorrhage occurred in 1 patient （Bleeding Academic Research Consortium [BARC] Type 2） of the aspirin group, and 3 patients （1 BARC Type 2 and 2 BARC Type 5） in the no-aspirin group at 1-month follow-up （ χ2 = 0.005, P = 0.944）. New hemorrhage occurred in five patients in the no-aspirin group at 12-month follow-up. Three patients in the aspirin group while five patients in the no-aspirin group had recurrent dissection for endoleak at 1-month follow-up （2.3% vs. 2.2%, respectively, χ2 = 0.074, P = 0.816）. Four patients had new dissection in the no-aspirin group at 12-month follow-up （2.3% vs. 3.8%, respec

关键词： Acute Coronary Syndrome: Antiplatelet AorticDissection Endovascular Aortic Repair

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国内外众包研究综述

中国科技论坛 2017年第8期 59-68,151页

作者：严杰刘人境刘晗西安交通大学管理学院陕西西安710049 西安科技大学安全科学与工程学院陕西西安710054

回顾了众包现有的相关文献。首先,探讨了众包的定义、模式、组成及工作流程,构建了众包工作流程的一般框架。其次,围绕该框架对众包主体及其活动的相关研究进行了梳理,并阐述了众包的主要应用领域和负面问题;最后,构建了众包研究的理论... 详细信息

回顾了众包现有的相关文献。首先,探讨了众包的定义、模式、组成及工作流程,构建了众包工作流程的一般框架。其次,围绕该框架对众包主体及其活动的相关研究进行了梳理,并阐述了众包的主要应用领域和负面问题;最后,构建了众包研究的理论框架,总结了现有研究的不足以及提出未来可能的研究方向。

关键词：众包众包工作流程理论框架众包应用众包负面问题

Co-Culture of Early Embryo with Human Decidual Stromal Cells in vitro by Improvement of Early Embryo Development

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2000年第1期20卷 79-81页

作者：闫洁朱桂金刘建新艾继辉 Department of Obstetrics and Gynecology Tongji Hospital Tongji Medical University Wuhan 430030

Summary: An early embryo co-culture system with human decidual stromal cells was established to study its effect on early embryonic cleavage and growth in vitro. Three hundred and eight 2-cell mouse embryos were co-cultured with human decidual stromal cell monolayer in MEM+0. 4 % bovine serum albumin (BSA) and 163 embryos cultured in MEM+15 % FCS alone as control. Among the mouse 2-cell embryos co-cultured with human decidual stromal cells, 72.73 % developed to the morula stage and 67.21 % cavitated to blastocysts with 59. 74 % hatching, as compared with 61. 34 % to morula stage, 48. 47 % to blastocysts and none hatching in the controls, respectively. Co-cultured embryos cleaved slightly faster than controls and showed no or less fragmentation than those in the control. These results suggested that human decidual stromal cells can support early embryonic development and yield a reasonable number of embryos with good quality up to blastocyst stage.

关键词： human decidual stromal cells embryo co-culture

汶川地震前地震活动特征的普遍性及其机理探讨

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地球物理学报 2018年第5期61卷 1891-1906页

作者：薛艳刘杰宋治平黎明晓中国地震台网中心北京100045

汶川地震前地震活动较为显著的异常是:1970—2008年汶川地震前,从云南北部至甘青川交界形成规模巨大的5.5级以上地震活动增强区(或称环形分布);1970—1999年围绕龙门山断裂带形成5级以上地震背景空区,汶川地震发生在增强区内的背景地震... 详细信息

汶川地震前地震活动较为显著的异常是:1970—2008年汶川地震前,从云南北部至甘青川交界形成规模巨大的5.5级以上地震活动增强区(或称环形分布);1970—1999年围绕龙门山断裂带形成5级以上地震背景空区,汶川地震发生在增强区内的背景地震空区里;2001—2007年形成ML4.0以上地震孕震空区,震前1年孕震空区内部及其两端相继发生多次ML4.0~5.0地震,空区打破.上述地震活动增强区、背景空区和孕震空区是大地震前普遍出现的现象.为对比分析,本文系统研究了2001年以来我国大陆及邻区4次MS≥7.8级地震和全球10次MW≥8.0级地震前类似地震活动异常,并给出统计特征.结果显示:地震增强区规模为850~2700km,持续时间13—38年,增强区长轴对数与主震震级呈正相关关系.增强区与余震区规模之比为2.3~7.7,其对数与主震震级呈负相关.背景空区长轴300~1100km,持续时间10—32年,其长轴对数与主震震级呈正相关关系.孕震空区长轴为370~780km,持续时间1—7年,孕震空区长轴对数与主震震级呈正相关关系.对于板内地震,构成增强区的最低震级为5.0级或5.5级,构成背景空区和孕震空区的最低震级分别为5.0级和4.0级.而对于板间地震,构成增强区和背景空区的最低震级为6.0级或6.5级,构成孕震空区的最低震级为5.0级或5.5级.基于坚固体地震孕育模型,认为地震活动增强区的环形分布是由于震源区的破裂强度高于周围介质造成的,地震孕育过程中体应变的范围和强度存在逐渐增大和变小的过程,这是地震活动增强区出现三阶段特征的原因.从包体弹性理论可以推导出增强区尺度的对数与主震震级、增强区与震源体比值的对数与主震震级存在线性关系.

关键词：汶川地震地震活动增强区背景空区孕震空区坚固体孕震模型

Problems of Quality of Migrant Workers and Countermeasures from the Perspective of Iceberg Model

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Asian Agricultural Research 2012年第5期4卷 48-50页

作者： yan Yu-jie,liu Yuan The College of Management,Shaanxi University of Science and Technology,Xi’an 710021,China

From the perspective of Iceberg Model,we analyze levels and structures of quality of migrant workers from knowledge,skills,social role, self-cognition,traits and motives. On the basis of these situations,we put forward countermeasures: value rural education and enhance skill training; make clear occupational planning and set up correct sense of value; assist migrant workers in facing the reality and adjusting their state of mind in working; coordinate interest relationship and call upon social care; rebuild mental world and construct harmonious society.

关键词： Iceberg Model Quality of migrant workers Problems

集中,分组,分组后集中:探究三种群体结构对群体决策能力的影响

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运筹与管理 2016年第5期25卷 6-14页

作者：严杰刘人境徐搏西安交通大学管理学院陕西西安710049

采用基于Agent仿真的方法,研究决策问题不可分时,集中网络、分组网络、分组后集中网络对群体决策能力的影响。三种群体结构分别对应于三种群决策模式:集中决策、分组决策、分组后集中决策。仿真结果表明,仅当问题较为简单、分组适当、... 详细信息

采用基于Agent仿真的方法,研究决策问题不可分时,集中网络、分组网络、分组后集中网络对群体决策能力的影响。三种群体结构分别对应于三种群决策模式:集中决策、分组决策、分组后集中决策。仿真结果表明,仅当问题较为简单、分组适当、个体学习速率较低时,分组决策才小幅优于集中决策。分组后集中决策并不受问题复杂度、分组数和个体学习速率的影响,总是优于集中决策和分组决策。但为了提高分组后集中决策的决策能力,面对简单问题时,应适当减少分组、维持较低的个体学习速率;面对复杂问题时,应适当增加分组、维持适中的个体学习速率。此外,分组后集中决策的集中时机与群体决策能力呈倒U关系,并不受问题复杂度、分组数和个体学习速率的影响,但相对较早的集中时机更有利于解决很复杂的问题。

关键词：群体决策群体结构多主体仿真群体决策能力 NK模型