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Review of precipitation strengthening in ultrahigh-strength martensitic steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 256-269页

作者： Zhihao Tian Chunlei Shang Chaolei Zhang Xiaoye Zhou Honghui wu Shuize Wang Guilin wu Junheng Gao Jiaming Zhu Xinping Mao Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China Institute of Steel Sustainable Technology Liaoning Academy of MaterialsShenyang 110004China Department of Materials Science and Engineering Shenzhen MSU-BIT UniversityShenzhen 518172China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China School of Civil Engineering Shandong UniversityJinan 250061China

Martensite is an important microstructure in ultrahigh-strength steels,and enhancing the strength of martensitic steels often involves the introduction of precipitated phases within the martensitic *** considerable research efforts devoted to this area,a systematic summary of these advancements is *** review focuses on the precipitates prevalent in ultrahigh-strength martensitic steel,primarily carbides(e.g.,MC,M_(2)C,and M_(3)C)and intermetallic compounds(e.g.,Ni Al,Ni_(3)X,and Fe_(2)Mo).The precipitation-strengthening effect of these precipitates on ultrahigh-strength martensitic steel is discussed from the aspects of heat treatment processes,microstructure of precipitate-strengthened martensite matrix,and mechanical ***,a perspective on the development of precipitation-strengthened martensitic steel is presented to contribute to the advancement of ultrahigh-strength martensitic *** review highlights significant findings,ongoing challenges,and opportunities in the development of ultrahigh-strength martensitic steel.

关键词： ultrahigh-strength martensitic steel precipitation strengthening mechanical property carbide intermetallic compound

Estimation of Chloride Diffusivity in Hydrated Tricalcium Silicate Using a Hydration-Diffusion Integrated Method

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 49-64页

作者： WANG Xin SHEN Dejian TAO Sijie LIU Ruixin wu Shengxing College of Civil and Transportation Engineering Hohai UniversityNanjing 210098China

This study aims to develop a chloride diffusion simulation method that considers the hydration microstructure and pore solution properties during the hydration of tricalcium silicate(C3S).The method combines the hydration simulation,thermodynamic calculation,and finite element analysis to examine the effects of pore solution,including effect of electrochemical potential,effect of chemical activity,and effect of mechanical interactions between ions,on the chloride effective diffusion coefficient of hydrated C3S *** results indicate that the effect of electrochemical potential on chloride diffusion becomes stronger with increasing hydration age due to the increase in the content of hydrated calcium silicate;as the hydration age increases,the effect of chemical activity on chloride diffusion weakens when the number of diffusible elements decreases;the effect of mechanical interactions between ions on chloride diffusion decreases with the increase of hydration age.

关键词： tricalcium silicate simulation method chloride diffusion coefficient pore solution

微卫星不稳定状态对Ⅳ期结直肠癌患者化疗反应性和预后的影响

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中国癌症杂志 2015年第7期25卷 522-528页

作者：吴宇辰张长胜梁斐黄丹朱骥徐烨刘方奇复旦大学附属肿瘤医院大肠外科复旦大学上海医学院肿瘤学系上海200032 合肥市第二人民医院胃肠外科安徽合肥230011 复旦大学附属肿瘤医院临床统计中心复旦大学上海医学院肿瘤学系上海200032 复旦大学附属肿瘤医院病理科复旦大学上海医学院肿瘤学系上海200032 复旦大学附属肿瘤医院放疗科复旦大学上海医学院肿瘤学系上海200032

背景与目的:错配修复缺陷导致的微卫星不稳(microsatellite inistability,MSI)状态对Ⅱ、Ⅲ期结直肠癌患者的预后及化疗敏感性有重要作用,但在晚期肠癌中研究较少。该研究探讨微卫星不稳对晚期结直肠癌患者化疗敏感性及预后的影响。方法... 详细信息

背景与目的:错配修复缺陷导致的微卫星不稳(microsatellite inistability,MSI)状态对Ⅱ、Ⅲ期结直肠癌患者的预后及化疗敏感性有重要作用,但在晚期肠癌中研究较少。该研究探讨微卫星不稳对晚期结直肠癌患者化疗敏感性及预后的影响。方法:收集采用XELOX或FOLFOX为一线化疗方案的Ⅳ期肠癌患者的原发肿瘤组织,免疫组化方法检测肿瘤组织中错配修复基因h MLH1、h MSH2、h MSH6和h PMS2的蛋白表达,分析微卫星状态与患者临床特征、预后及化疗反应的相关性。结果:共收集113例晚期结直肠癌患者,未发现MSI与患者总体生存时间(overall survival,OS)以及化疗敏感性存在相关。亚组分析中我们发现79例原发灶姑息性切除的患者中,MSI患者(22例)较MSS患者(57例)的中位无疾病进展时间(progression-free survival,PFS)明显延长(19.9个月vs 7个月,P=0.005),但MSI与OS无关(P=0.07)。对该79例患者预后行Cox多因素分析显示,MSI是影响患者PFS的独立危险因素(P=0.043,MSS/MSI,HR=2.079)。此外,该群患者的MSI状态与疾病控制率(59.1%vs31.6%,P=0.025)相关。结论:在原发灶姑息性切除的Ⅳ期结直肠癌患者中,微卫星不稳定状态与无疾病进展时间和化疗的疾病控制率呈正相关,因而有必要对该群患者进行微卫星检测。

关键词：晚期结肠直肠癌微卫星不稳定化疗预后

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ICU获得性肌无力患者功能评估的系统评价

中华危重病急救医学 2018年第12期30卷 1154-1160页

作者：吴雨晨丁楠楠姜变通张志刚张彩云李斌兰州大学护理学院甘肃兰州730000 兰州大学第一医院重症医学科甘肃兰州730000 兰州大学第一医院护理部甘肃兰州730000

目的探寻可用于评估ICU获得性肌无力(ICUAW)有效、客观的测量工具。方法通过计算机检索PubMed、Embase、Web of Science、Cochrane Library、中国知网(CNKI)、中国生物医学期刊全文数据库(CBM)、维普数据库、万方数据库,自建库至2018年7... 详细信息

目的探寻可用于评估ICU获得性肌无力(ICUAW)有效、客观的测量工具。方法通过计算机检索PubMed、Embase、Web of Science、Cochrane Library、中国知网(CNKI)、中国生物医学期刊全文数据库(CBM)、维普数据库、万方数据库,自建库至2018年7月1日发表的关于成人ICUAW评估、诊断的中、英文文献。由2名研究者独立筛选文献和质量评价,提取评估量表的研究设计类型、样本量、评估项目、信度和效度、研究对象、研究应用等指标,系统分析ICUAW评估工具、检查量表的可靠性和有效性,评价量表应用的现状及优缺点。结果最终纳入19篇有关量表信效度检验的文献。评估ICUAW的方法有医学研究委员会肌力评分(MRC-Score)、巴氏指数(BI)、6min步行试验(6MWT)、临床结局变量量表(COVS)、切尔西物理功能评估量表(CPAx)、功能独立性测评(FIM)、危重患者功能状态评分(FSS-ICU)、危重患者移动能力量表(IMS)、移动指数(RMI)、佩尔梅危重患者活动评分(PERME)、危重症物理功能测试量表(PFIT)、危重症物理功能测试评分量表(PFIT-s)、手术患者最佳移动评分量表(SOMS)和曼彻斯特移动评估量表(MMS)等14个量表和超声评估。有9个量表(60%)进行了信度检验,其中评定者间信度波动在0.600~0.996,复测信度为0.970,内在一致性波动于0.680~0.992。有6个量表(40%)进行了效度检验,其中结构效度为0.57~0.94,内容效度波动于0.830~0.988,同时效度波动在0.730~0.823。说明目前ICUAW评估量表信度相对较好,但准确评估ICUAW程度相对较低。根据评估内容可以将ICUAW量表归纳为三大类:第一类以MRC-Score量表为代表的躯体各部分肌力评估的量表;第二类为评估躯体功能和转移能力的量表,如COVS、CPAx、FIM、FSS-ICU、IMS、PERME、PFIT、RMI、SOMS和MMS;第三类为评估日常活动能力和动作电位标记的量表,如6MWT、BI、超声。不同的量表评分与ICUAW患者住院时间、转归及病死率均有不同程度相关性,如COVS、CPAx、FSS-ICU、PFIT、SOMS能够预测患者住院时间及转归,RMI和SOMS能够预测ICU患者病死率,但它们之间的一致性尚无证据证明。目前较一致的观点认为超声等电生理标记评估ICUAW的观察节点为复合动作电位(CMAP)幅度<0.43~0.65mV,感觉神经动作电位(SNAP)幅度<17.6μV。结论ICUAW评估诊断工具较多,各个量表的信度相对较好,评估内容交错互印,未来的研究我们应该集各量表所长,探寻ICUAW评估的特异性指标,提高ICUAW评估诊断的准确性。

关键词： ICU获得性肌无力诊断量表系统评价

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华北地台东部中奥陶世岩相古地理特征

石油实验地质 2016年第5期38卷 559-568页

作者：林玉祥朱传真赵承锦吴玉琛李佳李秀芹山东科技大学地球科学与工程学院山东青岛266590

以明确华北地台中奥陶世沉积格局分布及演化特征为目的,基于层序地层学理论,将华北地台东部中奥陶统划分为5个三级层序,并以三级层序为单位进行沉积相分析和岩相古地理编图。从层序地层的等时性出发,研究了本区中奥陶世岩相古地理特征... 详细信息

以明确华北地台中奥陶世沉积格局分布及演化特征为目的,基于层序地层学理论,将华北地台东部中奥陶统划分为5个三级层序,并以三级层序为单位进行沉积相分析和岩相古地理编图。从层序地层的等时性出发,研究了本区中奥陶世岩相古地理特征。华北地台东部中奥陶世以持续海侵为主,层序地层的发展受海侵规模、时间及短暂海退的影响,中部地层发育最为齐全。古地理格局总体上表现为南北高、中间低,早期至晚期演化具有一定的继承性和明显的发展性。古地理环境受构造和海平面变化综合作用的影响,随着海侵扩大,云坪沉积减少,局限台地和开阔台地占据绝对优势。各期沉积相的分布格局有所差异,但整体而言,继承性明显,南北两侧的隆升格局造成南北分化显著,沉积相带南北对称,开阔台地常为南北两侧的局限台地所夹持,反映了构造隆升背景下沉积环境对海平面变化的敏感性。沉积过程的多旋回性和岩性组合的韵律性使得中奥陶统形成了多套有利的生储盖组合,中新生界保存条件较好的渤海湾盆地区为有利勘探区。

关键词：沉积相岩相古地理层序地层中奥陶世华北地台东部

Mechanism Study on the Effect of Retarder on Polyurethane Setting Time Based on Molecular Simulation

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Journal of wuhan University of Technology(Materials Science) 2025年第1期40卷 224-231页

作者： wu Yuxuan XU Wenyuan YU Tianlai JI Yongcheng School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

This study identified castor oil and phosphate ester as effective retarders through setting time,tensile,and flexural tests,and determined their optimal *** mechanism by which phosphate ester affects the setting time of polyurethane was further investigated using molecular dynamics *** transform infrared spectroscopy was also employed to systematically study the physical and chemical interactions between phosphate esters and polyurethane *** results demonstrate that a 1%concentration of phosphate ester provides the most effective retarding effect with minimal impact on the strength of *** phosphate ester is added to the B component of the two-component polyurethane system,its interaction energy with component A decreases,as do the diffusion coefficient and aggregation degree of component B on the surface of component *** reduction in interaction slows the setting ***,the addition of phosphate ester to polyurethane leads to the disappearance or weakening of functional groups,indicating competitive interactions within the phosphate ester components that inhibit the reaction rate.

关键词： polyurethane retarder setting time molecular dynamics diffusion coefficient

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang wu The International Centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries

基于食品安全的企业社会责任缺失原因与改进路径分析

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粮食科技与经济 2018年第5期43卷 41-43页

作者：王茂祥李群吴雨晨南京理工大学经济管理学院江苏南京210094 中国移动通信集团江苏有限公司江苏南京210029 常州大学商学院江苏常州213164

食品安全与消费者的生命健康关联密切。本文分析了与食品安全相关的企业社会责任内涵,以及目前相关社会责任缺失的原因,在此基础上,提出了基于食品安全的企业社会责任改进路径。通过促进食品企业建立社会责任管理体系、强化社会各界对... 详细信息

食品安全与消费者的生命健康关联密切。本文分析了与食品安全相关的企业社会责任内涵,以及目前相关社会责任缺失的原因,在此基础上,提出了基于食品安全的企业社会责任改进路径。通过促进食品企业建立社会责任管理体系、强化社会各界对食品安全的监督及健全相关法律法规并强化执行力度等措施,可促进食品企业在追求经营绩效的同时,更好地承担社会责任,切实保障食品安全。

关键词：食品安全企业社会责任缺失原因改进路径

The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study

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Neural Regeneration Research 2025年第5期20卷 1505-1512页

作者： Jieying wu Shan Ye Xiangyi Liu Yingsheng Xu Dongsheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor *** bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to ***,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is *** address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral *** used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis *** factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb *** results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis *** findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis.

关键词： amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread