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CO_2 Corrosion and Grooving Corrosion Behavior of the ERW Joint of the Q125 Grade Tube Steel

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Journal of Iron and Steel Research International 2015年第10期22卷 943-948页

作者： Li-dong WANG feng-lei liu Qing-yun ZHAO Hui-bin WU AVIC Beijing Aeronautical Manufacturing Technology Research Institute University of Science and Technology Beijing

In order to investigate the CO2 corrosion behavior and the grooving corrosion susceptibility of electric resistance welded tubes of the Q125 grade, the high temperature and high pressure autoclave was employed to conduct CO2 corrosion experiments for the welded joint. The mechanisms of grooving corrosion and the factors influencing grooving corrosion susceptibility were identified by electrochemical measurement, microstructure observation, residual stress examination, micro-region composition and orientation analysis. The CO2 corrosion results show that the corrosion resistance of the base material is the best, followed by heataffected zone and the welded seam is the worst. The grooving corrosion occurred in the welded seam, and the grooving corrosion susceptibility of welded seam is relativity high. The dominated reason for the grooving corrosion of the electric resistance welded joint is the notable inclusions consisting of MnS as the main content in the welded seam. The proportion of high-angle grain boundaries in the welding zone is higher than that of base metal and the heat affected zone, which plays an important role in the corrosion behavior of the welded seam.

关键词： welded joint grooving corrosion CO2 corrosion Q 125 grade tube steel high-angle grain boundary

Comparison Between the Effects of 2-Selenium Bridged β-Cyclodextrin and Ebselen on Treating SHRsp Stroke

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Chemical Research in Chinese Universities 2008年第3期24卷 322-329页

作者： JIA Zhi-dan LIN feng liu lei MU Ying YAN Gang-lin LUO Gui-min Key Laboratory for Molecular Enzymology and Engineering of the Ministry of Education Jilin University Changchun 130021 P R. China

A glutathione peroxidase（GPX） mimic, 2-selenium bridged β-cyclodextrin（2-SeCD）, was synthesized. In order to examine its role and mechanism in treating stroke we chose stroke-prone spontaneously hypertensive rats（SHRsp） as animal model. 56 SHRsps of 8-week olds were randomly divided into several groups： test groups （low, moderate, high dose of 2-SeCD） and control groups（positive and negative）. After onset of the stroke, the rats in test groups were orally administrated with different amounts of 2-SeCD, the positive control group with ebselen, and the negative control group with drinking water. The treatment lasted two weeks, followed by observation of the rats for 10 days, meanwhile blood pressure, biochemical parameters of plasma, and the contents of nitric oxide（NO） and malondialdehyde（MDA） in plasma and brain were determined. The results show that there were significant differences in contents of NO and MDA in plasma and brain between the test groups（high, moderate dose of 2-SeCD） and negative control group. The NO contents of the test groups were obviously higher than that of the negative control group （P〈0.01）. The MDA contents of the test groups（high, moderate dose of 2-SeCD） were obviously lower than that of the negative control group（P〈0.01）. The mechanism of 2-SeCD in treating stroke was discussed, which maybe related to the increase of NO and the decrease of MDA in plasma and brain tissue, but the exact mechanism should be further studied. Moreover, the tendencies of changes in systolic blood pressure, contents of NO and MDA, and other physiological parameters for the test groups were shown to be much better than the corresponding parameters for the positive group（the group with ebselen）（P〈0.05）, indicating that the treatment effect of 2-SeCD is better than that of ebselen.

关键词： 2-Selenium bridged β-cyclodextrin Glutathione peroxidase Enzyme mimic Stroke Stroke-prone spontaneously hypertensive rat Nitric oxide Malondialdehyde

Reconstruction of Gene Regulatory Networks Based on Two-Stage Bayesian Network Structure Learning Algorithm

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Journal of Bionic Engineering 2009年第1期6卷 86-92页

作者： Gui-xia liu, Wei feng, Han Wang, lei liu, Chun-guang ZhouCollege of Computer Science and Technology, Jilin University, Changchun 130012,P.R. China [a]College of Computer Science and Technology Jilin University Changchun 130012 P. R. China

In the post-genomic biology era,the reconstruction of gene regulatory networks from microarray gene expression data is very important to understand the underlying biological system,and it has been a challenging task in *** Bayesian network model has been used in reconstructing the gene regulatory network for its advantages,but how to determine the network structure and parameters is still important to be *** paper proposes a two-stage structure learning algorithm which integrates immune evolution algorithm to build a Bayesian *** new algorithm is evaluated with the use of both simulated and yeast cell cycle *** experimental results indicate that the proposed algorithm can find many of the known real regulatory relationships from literature and predict the others unknown with high validity and accuracy.

关键词： gene regulatory networks two-stage learning algorithm Bayesian network immune evolutionary algorithm

Heavy flavor quenching and flow:the roles of initial condition,pre-equilibrium evolution,and in-medium interaction

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Chinese Physics C 2020年第11期44卷 127-137页

作者： Shu-Qing Li Wen-Jing Xing feng-lei liu Shanshan Cao Guang-You Qin Department of Physics and Information Engineering Jining UniversityQufu 273155China Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTexas77843USA Department of Physics and Astronomy Wayne State UniversityDetroitMichigan 48201USA Nuclear Science Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

Within an advanced Langevin-hydrodynamics framework coupled to a hybrid fragmentation-coalescence hadronization model,we study heavy flavor quenching and flow in relativistic heavy-ion *** investigate how the initial heavy quark spectrum,the in-medium energy loss and hadronization mechanisms of heavy quarks,the evolution profile of the pre-equilibrium stage,the medium flow,and the temperature dependence of heavy quark diffusion coefficients influence the suppression and elliptic flow of heavy mesons at the RHIC and the *** results show that the different modeling of initial conditions,pre-equilibrium evolution,and in-medium interactions can individually yield uncertainties of approximately 10-40% in D meson suppression and flow at a low transverse *** also find that proper combinations of collisional versus radiative energy loss,coalescence versus fragmentation in hadronization,and the inclusion of medium flow are the most important factors for describing the suppression and elliptic flow of heavy mesons.

关键词： quark-gluon plasma heavy-ion collisions jet quenching heavy quark

State of research and trends in development of wood adhesives

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Forestry Studies in China 2011年第4期13卷 321-326页

作者： ZHAO lei-feng liu Yu XU Zheng-dong ZHANG Ya-zhuo ZHAO Fang ZHANG Shuang-bao College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

We aim to present an overview of the status of adhesives in the wood industry, especially in the area of wood-based panels. The review summarizes the current state of research of two kinds of adhesives, i.e., synthetic adhesives and natural adhesives. Synthetic adhesives, consisting of urea-formaldehyde resins （UF）, phenol-formaldehyde resins （PF）, polyvinyl acetate emulsion （PVAc） and isocyanates, are widely used. For UF, most investigations are concerned with the reduction of free formaldehyde; for PF, most studies focus on finding new chemicals to replace phenol. PVAc has poor properties, but these can be improved by a blending reactions and copolymerization with other chemicals. Isocyanate is an environmentally friendly synthetic adhesive, but also suffers from inadequate properties. Natural adhesives, such as protein/starch, lignin and tannins, have poor bonding effect that limits their level of use, but their main advantages are that they are environmentally friendly and a renewable resource. Studies of modification can improve the bonding performances and gradually cause natural adhesives to become applied in industrial production. Some proposals for future development and the importance of environmentally friendly adhesives are provided, which will be helpful in future theoretical and experimental research.

关键词： synthetic adhesives natural adhesives main features development trend

Effects of two methods of reconstruction of digestive tract after total gastrectomy on gastrointestinal motility in rats

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World Journal of Gastroenterology 2003年第5期9卷 1051-1053页

作者： Xin-Yu Qin Yong lei feng-Lin liu Department of General Surgery,ZhongShan Hospital,Fudan University,Shanghai 200032,China Department of General Surgery ZhongShan Hospital Fudan University Shanghai 200032 Chin

AIM: To compare the effects of Roux-en-Y and jejunum interposition reconstruction procedures after total gastrectomy on intestinal ***: Fifty male Sprague-Dawley rats were randomly divided into 5 groups: the control group (C), the laparotomy group (L), the jejunal transection group (JT) where the jejunum was transected 10 cm distal from the Treitz ligament and anastomosed, the Roux-en-Y group (RY) and the jejunal interposition group (JI) after total gastrectomy. To evaluate intestinal transit, the animals were given 0.1 ml Evans Blue solution through an orogastric tube. The rats were executed by CO2 inhalation 30 minutes later and the intestinal transmit was determined as the distance between the site of esophageojejunal anastomosis and the most distal site of small intestine colored with ***: One month after operation, the body weight of rats among JI and RY were almost identical (274.6±9.5 vs 270.4±10.6, P＞0.05), but were significantly lighter than those of JT and L group. Four months after the operation, the body weight in the JI group increased compared to the preoperative level (345.2±15.7 g vs 299.5±8.3 g, P＜0.01).However, the body weight of RY group decreased compared to preoperative (255.1±11.3 g vs 295.0±12.0 g, P＜0.01).The difference was more significant at six months postoperative. Small bowel transmit time in RY was slower than that in JI group and C group (P＜0.01).CONCLUSION: Changes of body weight and intestinal motility in JI group are less influenced than in RY group.

关键词：胃肠动力学全胃切除术胃肠道重建手术方式动物实验

Extended operation for thoracic malignancies invading superior vena cava and/or innominate vein

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Chinese Medical Journal 2007年第14期120卷 1277-1280页

作者： ZHAI Chun-bo YU feng-lei WANG Xiang liu Wen-liang HU Jian-guo LU Wei-dong ZHANG Ming Department of Cardiothoracic Surgery Second Xiangya Hospital Central South University Changsha 410011 China

Patients with thoracic malignancies invading the superior vena cava （SVC） and innominate vein that cause venous flow obstruction have a poor quality of lite and short survival time. Dartevelle et al reported that the 3-year survival rates were 27% for patients with mediastinal malignancies and non-small cell lung cancer. Recently, some surgeons＇ experience suggested that the results of extensive resection and reconstruction of the SVC and innominate vein were excellent. From May 2003 to December 2005, radical resection and reconstruction of the SVC and/or innominate vein were performed in a group of patients for mediastinal or lung tumors invading the superior vena cava and/or innominate vein. We reported our experience in this retrospective study to explore the operative method, the optimal vascular graft, and the benefits of extended resection and reconstruction of SVC and/or innominate vein for invasive thoracic tumors.

关键词： mediastinal neoplasms superior vena cava syndrome superior vena cava reconstruction extended operation

聚丙烯腈树脂基固态胺吸附剂的制备及其对CO_2吸附性能研究

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高分子学报 2018年第7期28卷 886-892页

作者：刘风雷陈水挟符文皓中山大学化学学院广州512075

以丙烯腈(AN)为单体,二乙烯苯(DVB)为交联剂,采用悬浮聚合法制备了多孔聚丙烯腈聚合物(PAN),进一步通过胺化反应制备了含有较高密度胺基的固态胺吸附材料.利用N2吸附-脱附等温线、扫描电子显微镜(SEM)、热重分析(TG)等方法表征了吸附材... 详细信息

以丙烯腈(AN)为单体,二乙烯苯(DVB)为交联剂,采用悬浮聚合法制备了多孔聚丙烯腈聚合物(PAN),进一步通过胺化反应制备了含有较高密度胺基的固态胺吸附材料.利用N2吸附-脱附等温线、扫描电子显微镜(SEM)、热重分析(TG)等方法表征了吸附材料的结构和形貌.研究了有机胺化试剂类型对所制备的材料结构的影响,以及吸附温度、湿度等对其CO_2吸附性能的影响.研究结果表明,当吸附温度为25°C、流速为30 m L/min、CO_2浓度为10%、有机胺为四乙烯五胺(TEPA)时,固态胺吸附材料PAN-TEPA对CO_2的吸附量可达1.87 mmol/g.水的存在能显著提高PAN-TEPA的吸附量,饱和水蒸气下,其对CO_2的平衡吸附量为2.97 mmol/g.动力学研究发现,Avrami模型能很好地拟合PAN-TEPA在不同温度下的吸附过程,揭示PAN-TEPA对CO_2的吸附过程是物理吸附和化学吸附共同作用的效果.经过10次循环再生吸附后,PAN-TEPA的吸附量仍可以达到初始吸附量的98%.上述研究结果表明,PANTEPA对CO_2具有良好的吸附性能和稳定的再生性能,其在CO_2的捕集方面具有重要的应用前景.

关键词： CO2 吸附多孔性聚合物动力学

基层执法的“双轨制”模式——以计划生育执法为例

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华中科技大学学报（社会科学版） 2017年第1期31卷 99-110页

作者：陈柏峰刘磊中南财经政法大学法学院湖北武汉430073 四川大学法学院四川成都610207

基层执法是法治建设的关键环节,计划生育执法能体现基层执法的一般模式与实践机制。计划生育执法在之前的连带责任模式衰落后,逐渐走向了"双轨制"模式:强调依法行政的法治轨道与强调执行实效的治理轨道并行。在法治轨道上,执法队伍建设... 详细信息

基层执法是法治建设的关键环节,计划生育执法能体现基层执法的一般模式与实践机制。计划生育执法在之前的连带责任模式衰落后,逐渐走向了"双轨制"模式:强调依法行政的法治轨道与强调执行实效的治理轨道并行。在法治轨道上,执法队伍建设正规化,执法权行使规范化,执法过程程序化,强调依法行政、尊重人权,但执法任务难以有效完成。治理轨道成为应对困境的重要选择,它通过压力型体制实现体制内动员,通过半正式行政实现权力的末梢延伸,体现基层治理的综合性,是法治轨道构成的有效补充。执法"双轨制"模式是治理转型的产物,既顺应了依法行政、尊重人权的现代法治潮流,也可以提高执法实效,回应基层法治的非规范性、综合性和延伸性,因此可能会存续较长时间。

关键词：基层执法计划生育 “双轨制” 法治治理