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Influence Mechanism of Cerium on the Threshold of Short Fatigue Crack for Aluminum-lithium Alloy 2090

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Rare Metals 2001年第1期20卷 32-37页

作者： Zheng Chen, yongxin wang, Bing Liu, Xiaoling Li, Qilong Wei (School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China) Northwestern Polytech Univ Sch Mat Sci & Engn Xian 710072 Peoples R China

The thresholds of short fatigue cracks for aluminum-lithium alloys 2090 and 2090+Ce are quantitatively evaluated. The essential reason resulting in stronger short crack effect has been ascertained. Influence of cerium on the threshold of short fatigue cracks for aluminum-lithium alloy 2090 was investigated. The results show that, by adding Ce into this alloy, DeltaK(i) and DeltaK(***) are increased. The influence mechanism of Ce on the threshold of short fatigue crack for alloy 2090 was explored fi om the bound energy, T, phase, the energy of anti-phase boundary, the energy of super-lattice intrinsic stacking fault and the electron bonds. By adding Ce into alloy 2090, the bound energy of Cu atom in this alloy is increased; the effect of thinning and dispersing T, phase is obtained; the effect of increasing the energy of anti-phase boundary and decreasing the energy of super-lattice intrinsic stacking fault for delta ' phase can be achieved.

关键词： aluminum-lithium alloy Ce short fatigue crack bound energy fault energy

2018-2022年天津市急性乙型病毒性肝炎流行特征及病毒基因型分析

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公共卫生与预防医学 2025年第2期36卷 17-21页

作者：张国平王永馨何海艳刘勇吴伟慎天津市疾病预防控制中心天津300011

目的了解近年来天津市急性乙型病毒性肝炎(乙肝)的流行特点和基因型分布,寻找基因型与流行特征的关联。方法收集天津市2018-2022年国家传染病监测系统报告的现住址为天津的急性乙肝病例信息,通过医院系统查阅检验记录和电话调查随访病... 详细信息

目的了解近年来天津市急性乙型病毒性肝炎(乙肝)的流行特点和基因型分布,寻找基因型与流行特征的关联。方法收集天津市2018-2022年国家传染病监测系统报告的现住址为天津的急性乙肝病例信息,通过医院系统查阅检验记录和电话调查随访病例转归,使用荧光PCR方法检测乙肝病毒(HBV)基因型。结果2018-2022年天津市报告现住址为本地的急性乙肝患者387例,年均报告发病率0.52/10万,总体呈下降趋势(2=28.553,P<0.001);男女报告发病率之比1.68,年龄分布主要集中在30~65岁年龄段,其中35~39岁年龄组报告发病率最高(1.22/10万);72.87%的病例确诊6个月后随访HBsAg转阴;干部职员的转阴比例(92.16%)明显高于未转阴的比例(0%),转阴组ALT中位数(1508.00 U/L)明显高于未转阴组(976.00U/L);315份基因分型成功的病例中,81.27%为C基因型,14.92%为B基因型47例;B基因型急性乙肝患者的ALT中位数(1585.00 U/L)明显高于C基因型(988.00U/L)。结论天津市急性乙肝报告发病率较低,且呈下降趋势,青壮年男性好发,基因型以C基因型为主,B基因型的HBV对急性乙肝患者的肝脏损害更严重。

关键词：乙肝急性流行特征基因型

Bisulfite-mediated base-free decarboxylative carbonylsulfination of alkenes:access toβ-keto sultines

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Science China Chemistry 2025年第2期68卷 622-630页

作者： yongxin Zhang Pan Zhou Xinyue Ma Xiaoxiao Yang Xing Fang Yuxi wang Chao Shu State Key Laboratory of Green Pesticide Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon ReductionCCNU-uOttawa Joint Research CentreCollege of ChemistryCentral China Normal University(CCNU)Wuhan 430079China Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Normal UniversityWuhu 241000China

A straightforward three-component decarboxylative cross-coupling ofα-keto acids,alkenes and sodium bisulfite is established for the construction of otherwise challenging-to-accessβ-keto sultine *** reaction involves the photoinduced carbonylsulfination of alkenes and utilizes sodium bisulfite as both a sulfur dioxide surrogate and buffer agent for deprotonation ofα-keto carboxylic *** note,the practical procedure featured broad substrate scope and group tolerance for diverse biologically important molecules under mild and operationally simple conditions,using an organic *** studies indicated that the transformation proceeds an apparent two-pronged radical addition/radical-polar crossover/SO_(2) insertion/ionic cyclization relay process,distinct from traditional alkenes bifunctionalization.

关键词： photoredox catalysis β-keto sultines carbonylsulfination sodium bisulfite radical

基于弱磁检测的海洋钻修机智能钢丝绳在线检测系统

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船电技术 2025年第3期45卷 53-56页

作者：王永新常双利王昌力焦明伟巩德鑫任新建中海油田服务股份有限公司天津300451

本研究开发了一种智能钢丝绳在线检测系统,采用磁记忆式弱磁检测技术,实现了对海洋钻修机钢丝绳健康状况的实时检测。系统融合了先进的传感器技术、数据分析技术和互联网技术,显著提升了检测的准确性和效率。通过机器视觉损伤检测、磁... 详细信息

本研究开发了一种智能钢丝绳在线检测系统,采用磁记忆式弱磁检测技术,实现了对海洋钻修机钢丝绳健康状况的实时检测。系统融合了先进的传感器技术、数据分析技术和互联网技术,显著提升了检测的准确性和效率。通过机器视觉损伤检测、磁记忆规划装置和弱磁检测装置,系统能够全面识别钢丝绳的断丝、磨损、锈蚀和疲劳损伤。该系统的设计注重海洋环境的稳定性和可靠性,通过需求分析、硬件选型、软件开发、系统集成与测试,最终实现了在海洋钻修机上的现场应用。系统的实施不仅提高了钢丝绳的安全性和检测智能化水平,还有效解决了安全管理难题,提升了海洋钻修机作业的安全性和效率,具有重要的应用价值。

关键词：海洋钻修机钢丝绳在线检测系统磁记忆规划弱磁检测系统

Microscopic Phase-field Simulation of Effects of Re-ageing Temperature on Precipitation of Ni-Al-Cr Alloys

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Chinese Journal of Aeronautics 2009年第5期22卷 551-557页

作者： Zhang Jixiang Chen Zheng Lai Qingbo Zhao Yan wang yongxin School of Materials Science and Engineering State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China School of Materials Engineering Yancheng Insititute of Technology Yancheng 224051 China

This article, by means of the ternary microscopic phase-field model, investigates the effects of re-ageing temperature on the precipitation of Ni75Al10Cr15 alloy with the help of atomic pictures, order parameters, particle density, averaged radii, and volume fractions. During pre-ageing at 873 K, DO22 phases first appear through spinodal decomposition mechanism, and then L12 phases begin to form on the DO22 phase-boundaries through non-classical nucleation mechanism. In either of them, ordering process is obviously faster than atom clustering. At the late stage of re-ageing at 923 K, the elastic strain energy seems to exert stronger effects on microstructure, and DO22 and L12 phases exhibit directional alignment along 〈100〉 direction to a certain extent. When the temperature increases to 1 023 K, the influence of elastic strain energy begins to weaken, and the precipitated phases become randomly distributed in the matrix. The volume fraction of DO22 phase decreases to zero, whereas that of L12 phase first increases and then decreases with the temperature rising from 923 K to 1 123 K. On the whole, the effects of elastic strain energy make the coarsening behavior of both phases deviate from the time-law predictions by LSW diffusion-controlled growth theory.

关键词： Ni-Al-Cr alloy microscopic phase-field re-ageing nucleation order parameter

The effect of lactic acid bacteria inoculums on in vitro rumen fermentation, methane production, ruminal cellulolytic bacteria populations and cellulase activities of corn stover silage

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Journal of Integrative Agriculture 2020年第3期19卷 838-847页

作者： GUO Gang SHEN Chen LIU Qiang ZHANG Shuan-lin SHAO Tao wang Cong wang yongxin XU Qing-fang HUO Wen-jie College of Animal Sciences and Veterinary Medicines Shanxi Agricultural UniversityTaigu 030801P.R.China Institute of Ensiling and Processing of Grass Nanjing Agricultural UniversityNanjing 210095P.R.China

The objective of this study was to investigate the effect of lactic acid bacteria(LAB) inoculums on fermentation quality and in vitro digestibility of corn stover *** stover was ensiled without(control) or with Lactobacillus plantarum(LP),Enterococcus faecalis(EF),and Enterococcus mundtii(EM) for 45 *** fermentation characteristics were assessed,and subsequent in vitro dry matter digestibility(DM-D),neutral detergent fiber digestibility(NDF-D),volatile fatty acids(VFA),methane(CH4) production,cellulolytic bacteria proportions and their activities per corn stover silage were also *** was no significant difference(P>0.05) among the silage pH,lactic acid,crude protein(CP),water soluble carbohydrates(WSC) and lignocelluloses contents of different *** relative proportions of Ruminococcus flavefaciens and Fibrobacter succinogenes,carboxymethyl-ocellulose and β-glycosidase activities,DM-D,NDF-D,and VFA production of in vitro incubation was higher(P<0.05) for silages inoculated with LP and EF than those of the control *** inoculated with LP showed the lowest(P<0.05) CH4 production per unit yield of VFA,which was positively corresponded to the lowest(P<0.05) ratio of acetate to *** summary,the ensiling fermentation quality and subsequent utilization of corn stover silage were efficiently improved by inoculated with ***.

关键词： corn stover in vitro digestibility lactic acid bacteria silage

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水滑石焙烧产物脱除低浓度SO_2的研究

硅酸盐学报 2005年第2期33卷 206-208页

作者：王永新温州医学院浙江温州325003

研究了水滑石焙烧产物吸附低浓度SO2的性能和还原情况。实验表明:在大于600 ℃吸附温度下,焙烧的水滑石具有较好吸附性能。吸附剂本身制备条件对脱硫性能影响明显。负载Fe2O3后的复合金属氧化物吸附剂Fe2O3/Mg(Al)O吸附性能整 Mg(Al)O... 详细信息

研究了水滑石焙烧产物吸附低浓度SO2的性能和还原情况。实验表明:在大于600 ℃吸附温度下,焙烧的水滑石具有较好吸附性能。吸附剂本身制备条件对脱硫性能影响明显。负载Fe2O3后的复合金属氧化物吸附剂Fe2O3/Mg(Al)O吸附性能整 Mg(Al)O有明显提高。氢还原是再生吸附剂的合理和可靠的方法。

关键词：阴离子粘土水滑石脱硫二氧化硫

CsWRKY13,a novel WRKY transcription factor of Camellia sinensis,involved in lignin biosynthesis and accumulation

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Beverage Plant Research 2021年第1期1卷 97-105页

作者： Ruimin Teng yongxin wang Shijia Lin Yi Chen Yazhuo Yang Ni Yang Jingwen Li Jing Zhuang Tea Science Research Institute College of HorticultureNanjing Agricultural UniversityNanjing 210095China National Center for Tea Improvement Tea Research InstituteChinese Academy of Agricultural SciencesKey Laboratory of Tea Plant Biology and Resources UtilizationMinistry of AgricultureHangzhou 310008China

Lignin is an aromatic polymer that provides the necessary mechanical strength for the transport of water and nutrients in higher *** biosynthesis and accumulation affect growth and development of tea *** degree of lignification related to the tenderness of fresh tea leaves determines the quality of *** transcription factors play central roles in plant development and physiological ***,the roles of WRKY transcription factors in lignin biosynthesis of tea plants remain *** this study,a WRKY gene,CsWRKY13,was cloned from tea plant'Longjing 43'.The open reading frame(ORF)of CsWRKY13 gene was 708 bp,encoding 235 amino *** analysis showed that CsWRKY13 contained a conserved WRKYGQK amino acid sequence and a zinc-finger-like motif *** localization showed that CsWRKY13 was localized in the *** yeast trans-activation assay showed that CsWRKY13 had no transcriptional *** analysis showed that the CsWRKY13 gene was highly expressed in the *** of CsWRKY13 in Arabidopsis thaliana reduced lignin content and the expression levels of genes related to lignin biosynthesis in transgenic *** flavonoids pathway related genes were significantly *** study shows that CsWRKY13 might function as a negative regulator in regulation of lignin synthesis.

关键词： activation Camellia biosynthesis

Antisite defect types and temporal evolution characteristics of D0_(22)-Ni_3V structure:Studied by the microscopic phase field

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Science China(Physics,Mechanics & Astronomy) 2009年第8期52卷 1154-1160页

作者： ZHANG Jing,CHEN Zheng,ZHANG MingYi,LAI QingBo,LU YanLi & wang yongxin School of Material Science and Engineering,Northwestern Polytechnical University,Xi’an 710072,China School of Material Science and Engineering Northwestern Polytechnical University Xi’an China

Microscopic phase field simulation is performed to study antisite defect type and temporal evolution characteristic of D022-Ni3V structure in Ni75AlxV25-x ternary *** result demonstrates that two types of antisite defect VNi and NiV coexist in D022 structure;however,the amount of NiV is far greater than VNi;when precipitates transform from D022 singe phase to two phases mixture of D022 and L12 with enhanced Al:V ratio,the amount of VNi has no evident response to the secondary L12 phase,while NiV exhibits a definitely contrary variation tendency:NiV rises without L12 structure precipitating from matrix but declines with it;temporal evolution characteristic and temperature dependent antisite defect VNi,NiV are also studied in this paper:The concentrations of the both defects decline from high antistructure state to equilibrium level with elapsed time but rise with elevated temperature;the ternary alloying element aluminium atom occupies both α and β sublattices of D022 structure with a strong site preference of substituting α site.

关键词： antisite defect D022-Ni3V microscopic phase field