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High cycle fatigue performance at 650℃and corresponding fracture behaviors of GH4169 joint produced by linear friction welding

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Chinese Journal of Aeronautics 2025年第1期38卷 622-637页

作者： Shitong MA Xiawei YANG Zhenguo GUO yu SU Xinyuan HE Ju LI Jun TAO bo XIAO Wenya LI State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of Friction Welding TechnologiesSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Manufacturing Technology InstituteBeijing 100024China Department of Mechanical Engineering City University of HongKongHongKongChina

GH4169 joints manufactured by Linear Friction Welding(LFW)are subjected to tensile test and stair-case method to evaluate the High Cycle Fatigue(HCF)performance at 650℃.The yield and ultimate tensile strengths are 582 MPa and 820 MPa,*** HCF strength of joint reaches 400 MPa,which is slightly lower than that of Base Metal(BM),indicating reliable quality of this type of *** microstructure observation results show that all cracks initiate at the inside of specimens and transfer into deeper region with decrease of external stress,and the crack initiation site is related with microhardness of *** Electron Backscattered Diffraction(EBSD)results of the observed regions with different distances to fracture show that plastic deformation plays a key role in HCF,and the Schmid factor of most grains near fracture exceeds *** addition,the generation of twins plays a vital role in strain concentration release and coordinating plastic deformation among grains.

关键词： High cycle fatigue GH4169 superalloy Linear friction welding Fracture mechanism Microstructure evolution

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分级处遇视角下前科制度的多层构造研究

海峡法学 2025年第1期27卷 71-86页

作者：曹波白琳贵州大学法学院贵州省基层社会治理创新高端智库

我国现有前科制度未对犯罪人前科规范限制作适用上的区分,“轻重倒挂”的现象与轻罪治理的预期功能失衡,前科制度存废论争聚讼不已。尽管前科制度存在设定主体与设定方式规范阙如等不足之处,但前科制度在契合社会防卫价值追求、统合报... 详细信息

我国现有前科制度未对犯罪人前科规范限制作适用上的区分,“轻重倒挂”的现象与轻罪治理的预期功能失衡,前科制度存废论争聚讼不已。尽管前科制度存在设定主体与设定方式规范阙如等不足之处,但前科制度在契合社会防卫价值追求、统合报应预防刑罚目的等方面的正面价值使其无法被简单地消除或纯粹地否弃。前科制度改革理应紧密围绕其内在积极正面价值,坚持国家立法原则、比例原则和关联性原则,对照犯罪分层、刑罚个别化的理论指导以及宽严相济的政策指引,着眼于犯罪构成要素的实质差异,构建前科规范限制解除必要性量表,实行前科制度的分级处遇,同时健全司法救济等配套措施以确保前科规范限制解除实现应有之效。

关键词：前科前科消灭轻罪治理犯罪分层分级处遇

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桃花峰滑坡稳定性分析及治理效果研究

地下水 2024年第4期46卷 141-143,271页

作者：宋宝业白博宇李青青关鹏黄山市工程勘察院有限公司安徽黄山245000 武汉中地恒达科技有限公司湖北武汉430074 中国地质大学(武汉) 湖北武汉430074 岩土钻掘与防护教育部工程研究中心湖北武汉430074

以桃花峰滑坡为研究对象,结合滑坡基本情况分析了该滑坡的稳定性影响因素;采用剩余推力法计算了该滑坡三个代表性剖面的稳定性系数,并基于稳定性计算结果提出了削坡+格构梁锚杆+修建排水沟的滑坡治理方案;建立滑坡三维网格模型和地下水... 详细信息

以桃花峰滑坡为研究对象,结合滑坡基本情况分析了该滑坡的稳定性影响因素;采用剩余推力法计算了该滑坡三个代表性剖面的稳定性系数,并基于稳定性计算结果提出了削坡+格构梁锚杆+修建排水沟的滑坡治理方案;建立滑坡三维网格模型和地下水位模型,采用有限差分法计算了该滑坡在天然工况(不考虑地下水位)和暴雨工况(考虑地下水位)下的位移量分布,验证了所提出的治理方案的有效性,并通过对比分析表明地下水位对滑坡的稳定性具有较大影响,会导致滑坡体深部的土体位移。本研究对类似滑坡稳定性分析和治理方案设计和验证具有一定参考价值。

关键词：滑坡稳定性分析滑坡治理有限差分法地下水位滑坡位移

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聚多巴胺改性黄土的捕水特征及保水机制

化学工程 2025年第2期53卷 1-6,12页

作者：魏福龙白波王鹏乾长安大学水利与环境学院陕西西安710054 长安大学旱区地下水文与生态效应教育部重点实验室陕西西安710054 长安大学水利部旱区生态水文与水安全重点实验室陕西西安710054

黄土在中国分布广泛,其水敏性强,但保水性能差,制约了干旱地区农业生产发展。为改善黄土的吸水和保水性能,以PDA(聚多巴胺)为增强材料,采用高效复合表面修饰方法,制备具有优异捕水和保水性能的PDA@LS改性黄土,并研究其微观特征、官能团... 详细信息

黄土在中国分布广泛,其水敏性强,但保水性能差,制约了干旱地区农业生产发展。为改善黄土的吸水和保水性能,以PDA(聚多巴胺)为增强材料,采用高效复合表面修饰方法,制备具有优异捕水和保水性能的PDA@LS改性黄土,并研究其微观特征、官能团分布、热质量损失特性、吸水性能和保水性能,对失水过程进行动力学分析,探讨改性黄土的捕水和保水机制。结果表明:盐酸多巴胺与空载黄土的质量比为110时制备的改性黄土兼具低黏度和较好的流动性,饱和吸水量较空载黄土的0.2757 g/g提升至0.4742 g/g,开放环境下保水性能较空载黄土提升27.96%,并可多次进行水的解吸和复吸。动力学分析表明:PDA@LS改性黄土的恒温失水过程遵循Logarithmic模型,改性后的黄土中水分更易保持,有效水分扩散系数相比黄土降低56.02%,但易受温度的影响。PDA的改性极大改善了黄土吸水和保水性能,变黄土为“黑土”,对干旱地区土壤保水改良和水利用率的改善提供重要参考。

关键词：聚多巴胺改性黄土保水性能

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特殊超前支护液压支架的应用

煤炭技术 2019年第8期38卷 173-175页

作者：崔卫锋白育波王雨申雪荣文彦春西安重装铜川煤矿机械有限公司

旨在设计出一种新型的带式输送机顺槽巷道超前支护液压支架,能有效保障矿井综采生产,改善顶板的管理水平,保证带式输送机顺槽巷道设备及工作人员的人身安全,提高支护效率,降低支护成本,进而使平直移架得到保证,并且方便快捷地提高移架速... 详细信息

旨在设计出一种新型的带式输送机顺槽巷道超前支护液压支架,能有效保障矿井综采生产,改善顶板的管理水平,保证带式输送机顺槽巷道设备及工作人员的人身安全,提高支护效率,降低支护成本,进而使平直移架得到保证,并且方便快捷地提高移架速度,为实现高产、高效工作面提供安全有力的保证。

关键词：超前支架工作面安全

Transposable elements shape the landscape of heterozygous structural variation in a bird genome

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Zoological Research 2025年第01期 75-86页

作者： bo-Ping Li Na Kang Zao-Xu Xu Hao-Ran Luo Shi-yu Fan Xiao-Han Ao Xing Li Ya-Peng Han Xiao-Bin Ou Luo-Hao Xu Gansu Key Laboratory of Protection and Utilization for Biological Resources and Ecological Restoration in Longdong Longdong University Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City MOE Key Laboratory of Freshwater Fish Reproduction and Development School of Life Sciences Southwest University College of Medicine Longdong University Key Laboratory of Ministry of Education for the Coastal and Wetland Ecosystems College of the Environment and EcologyXiamen University

Avian genomes exhibit compact organization and remarkable chromosomal stability. However, the extent and mechanisms by which structural variation in avian genomes differ from those in other vertebrate lineages are poorly explored. This study generated a diploid genome assembly for the golden pheasant(Chrysolophus pictus),a species distinguished by the vibrant plumage of *** haploid genome assembly included complete chromosomalmodels,incorporatingall microchromosomes. Analysis revealed extensive tandem amplification of immune-related genes across the smallest microchromosomes(dot chromosomes), with an average copy number of 54. Structural variation between the haploid genomes was primarily shaped by large insertions and deletions(indels), with minimal contributions from inversions or duplications. Approximately 28% of these large indels were associated with recent insertions of transposable elements, despite their typically low activity in bird genomes. Evidence for significant effects of transposable elements on gene expression was *** strata on the sex chromosomes were identified, along with a drastic rearrangement of the W chromosome. These analyses of the high-quality diploid genome of the golden pheasant provide valuable insights into the evolutionary patterns of structural variation in avian genomes.

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Review of Molecular Simulation Method for Gas Adsorption/desorption and Diffusion in Shale Matrix

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Journal of Thermal Science 2019年第1期28卷 1-16页

作者： WANG Hui QU Zhiguo YIN Ying bai Junqiang yu bo School of Aeronautics Northwestern Polytechnical University MOE Key Laboratory of Thermo-Fluid Science and Engineering School of Energy and Power Engineering Xi'an Jiaotong University Mechanical Engineering College Beijing Institute of Petrochemical Technology

Shale gas is becoming an increasingly promising alternative energy resource because of its high efficiency and environment-friendly characteristic. The amount of adsorbed gas on the shale matrix surfaces and dissolved gas in the shale matrix bulk is the dominant factor in the long-term productivity of shale reservoir. Although experimental measurements have been extensively carried out to investigate the gas adsorption and diffusion properties in the shale matrix, they cannot provide the detailed information on the microscopic transport mechanism of shale gas during the gas production process. Molecular simulation can accurately visualize the gas adsorption/desorption and diffusion processes in the shale matrix. In the present study, the recent research advances of molecular simulation on gas adsorption/desorption and diffusion in the shale matrix are reviewed. Firstly, the density functional theory(DFT) for shale gas molecule desorption/adsorption on the surface of the matrix crystal is illustrated. Then, the grand canonical Monte Carlo(GCMC) method predicting the amount of shale gas desorption/adsorption in the shale matrix crystal is introduced. Finally, molecular dynamics simulation(MD) for gas diffusion in the shale matrix is elucidated. Further developments of the molecular simulation method in shale gas production are also discussed.

关键词： shale gas molecular simulation adsorption/desorption diffusion

Important role of lymphovascular and perineural invasion in prognosis of colorectal cancer patients with N1c disease

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World Journal of Gastroenterology 2025年第5期31卷 57-67页

作者： Zhi-Gang Sun Shao-Xuan Chen bai-Long Sun Da-Kui Zhang Hong-Liang Sun Huang Chen yu-Wan Hu Tong-Yin Zhang Zi-Han Han Wen-Xiao Wu Zhi-Yong Hou Li Yao Jian-Zheng Jie Department of General Surgery China-Japan Friendship HospitalBeijing 100029China Department of Radiology China-Japan Friendship HospitalBeijing 100029China Department of Pathology China-Japan Friendship HospitalBeijing 100029China Chinese Academy of Medical Science and Peking Union Medical College Beijing 100730China Institute of Clinical Medical Sciences China-Japan Friendship HospitalBeijing 100029China

BACKGROUND Lymphovascular invasion(LVI)and perineural invasion(PNI)are associated with decreased survival in colorectal cancer(CRC),but its significance in N1c stage remains to be clearly *** We retrospectively identified 107 consecutive patients who had CRC with N1c disease radically resected at our *** were reviewed for LVI and PNI by one pathologist blinded to the patients’***-free survival(DFS),overall survival(OS)and cancer-specific survival(CSS)were determined using the Kaplan-Meier method,with LVI and PNI prognosis differences determined by multivariate analysis using the Cox multiple hazards *** were compared using log-rank *** receiver operating characteristic(ROC)curve was used to evaluate the prognostic predictive *** The median follow-up time was 63.17(45.33-81.37)months for DFS,with 33.64%(36/107)of patients experiencing recurrence;21.5%of tumors were found to be LVI positive and 44.9%PNI *** 5-year DFS rate was greater for patients with LVI-negative tumors compared with LVI-positive tumors(74.0%vs 35.6%),and PNI was similar(82.5%vs 45.1%).On multivariate analysis,LVI[hazard ratio(HR)=3.368,95%confidence interval(CI):1.628-6.966,P=0.001]and PNI(HR=3.055,95%CI:1.478-6.313,P=0.002)were independent prognostic factors for *** patients could be divided into three groups of patients with different prognosis according to LVI and *** 5-year ROC curve for LVI,PNI and their combination prediction of DFS was 0.646,0.709 and 0.759,*** results were seen for OS and *** LVI and PNI could serve as independent prognostic factors of outcomes in N1c CRC *** with LVI or PNI should be given more attention during treatment.

关键词： Colorectal cancer N1c Lymphovascular invasion Perineural invasion Prognosis