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Effects of Si on the stability of retained austenite and temper embrittlement of ultrahigh strength steels

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 543-550页

作者： li-jun Wang Qing-wu Cai hui-bin Wu Wei Yu National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China

Effects of silicon （Si） content on the stability of retained austenite and temper embrittlement of ultrahigh strength steels were investigated using X-ray diffraction （XRD）,transmission electron microscopy （TEM）,and other experimental *** results show that Si can suppress temper embrittlement,improve temper resistance,and hinder the decomposition of retained *** austenite appears gradually with the increase of Si content during *** has a significant effect on enhancing carbon （C） partitioning and improving the stability of retained *** and C atoms are mutually exclusive in lath bainite,while they attract each other in austenite.ε-carbides are found in 1.8wt% Si steel tempered at 250℃,and they get coarsened obviously when tempered at 400℃,leading to temper *** ε-carbides but acicular or lath carbides lead to temper embrittlement in 0.4wt% Si steel,which can be inferred as cementites and composite *** embrittlement is closely related to the decomposition of retained austenite and the formation of reversed austenite.

关键词： silicon ultrahigh strength steel retained austenite temper embrittlement reversed austenite

Mossbauer spectroscopy studies on the particle size distribution effect of Fe–B–P amorphous alloy on the microwave absorption properties

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Nuclear Science and Techniques 2020年第3期31卷 10-19页

作者： Yu-Hua Lv Yan-hui Zhang Jian Zhang bin li School of Materials Science and Engineering Key Laboratory for Anisotropy and Texture of MaterialsMinistry of EducationNortheastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Institute of Advanced Magnetic Materials Hangzhou Dianzi UniversityHangzhou 310012China School of life Sciences Huzhou UniversityHuzhou 313000China

An Fe-based nanocrystalline alloy powder is important for application in microwave absorption,and the particle size has a critical impact on the electromagnetic microwave ***,it is necessary to study further the effects of the particle size on such parameters and improve the microwave absorption performance of Febased nanocrystalline *** this study,Fe-B-P particles were prepared through a synthetic approach consisting of an aqueous chemical reduction and a ball milling *** investigated the effects of ball milling on the microstructure and electromagnetic properties of Fe-B-P *** experimental results indicate that the Fe-B-P particles synthesized through an aqueous chemical reduction are amorphous ***-B-P particles with an original particle size of 200-1200 nm can be milled into an irregular shape with the size reduced to\500 nm after 0.5 h of ball milling,and subsequently,the particles become smaller with increases in the milling time,with traces of Fe2O3 generated on the particle *** results of the Mo¨ssbauer spectra show that a portion of the small particles demonstrate a superparamagnetic *** volume proportions of the superparamagnetic component increase from 13.1 to 15.8%as the treatment time *** measured the permittivity and permeability spectra of Fe-B-P particles within the frequency range of 2-18 *** reflection loss(RL)is-10 dB for an absorber thickness of 1.7-5.0 *** RL is-20 dB for an absorber thickness of 1.9-2.7 *** microwave absorption properties of samples with the same thickness are improved with an increase in the treatment time and are shifted to a higher frequency,which will broaden the bandwidth of the absorption as well.

关键词： Fe-B-P particles Mossbauer spectroscopy Microwave absorber properties

Potassium Acetate/18-Crown-6 Pair:Robust and Versatile Catalyst for Synthesis of Polyols from Ring-Opening Copolymerization of Epoxides and Cyclic Anhydrides

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Chinese Journal of Chemistry 2023年第1期41卷 83-92页

作者： Xiaoqing Dou Xiao-hui liu bin Wang Yue-Sheng li School of Materials Science and Engineering Tiangong UniversityTianjin 300387China Tianjin Key Lab of Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Efficient synthesis of polyester polyols with tunable molecular weight and microstructures from cyclic anhydride/epoxide mixtures by taking advantage of chain transfer reaction remains a great challenge,because most of the catalysts exhibit poor tolerance to chain transfer agent(CTA).In this contribution,we demonstrated that potassium acetate(KOAc)and 18-crown-6(18-C-6)combination has great potential in the synthesis of diverse polyester polyols with controllable molecular weight and high-end group ***-pared with KOAc,KOAc/18-C-6 pair could induce a much faster chain transfer between the active and dormant chains,and thus produce polyester polyols with narrow and monomodal *** addition,polyester polyols could be efficiently prepared in laboratory by using commercially available cyclic anhydride without further purification(containing about 2%diacid residual as CTA)with an extremely low catalyst loading([catalyst pair]:[anhydride]:[epoxide]=1:50000:250000,[catalyst pair]=0.0004 mol%).KOAc/18-C-6 could also promote the self-switchable copolymerization of cyclic anhydride/epoxide/cyclic ester ***-opening copolymerization of cyclic ester was initiated automatically after the full conversion of cyclic anhydride,finally producing polyester polyols with ABA-type block structure.

关键词： Ring-opening polymerization Macrocyclic ligands Block copolymer Cyclic Anhydride Epoxide

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氟唑菌酰胺的合成与生物活性

现代农药 2017年第4期16卷 12-14,34页

作者：王刚吕亮刘吉永单中刚杨辉斌李斌沈阳中化农药化工研发有限公司新农药创制与开发国家重点实验室沈阳110021

氟唑菌酰胺是巴斯夫公司开发的吡唑酰胺类杀菌剂。本文以二氟乙酰乙酸乙酯、原甲酸三乙酯和甲基肼等为起始原料经6步反应合成了氟唑菌酰胺,目标化合物的结构经~1H NMR确证。杀菌活性测试结果表明:氟唑菌酰胺对水稻纹枯病、黄瓜白粉病、... 详细信息

氟唑菌酰胺是巴斯夫公司开发的吡唑酰胺类杀菌剂。本文以二氟乙酰乙酸乙酯、原甲酸三乙酯和甲基肼等为起始原料经6步反应合成了氟唑菌酰胺,目标化合物的结构经~1H NMR确证。杀菌活性测试结果表明:氟唑菌酰胺对水稻纹枯病、黄瓜白粉病、大豆锈病具有优异的活性。

关键词：氟唑菌酰胺合成杀菌活性

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临近煤矿工作面油气井泄漏监测方法研究

煤炭技术 2025年第1期44卷 221-224页

作者：李辉中国地方煤矿有限公司北京100011

为了研究煤矿工作面附近油气井泄漏情况,采用对比分析法,在煤矿工作面附近的油气井、井下工作面附近巷道和采空区中采集了一定量的气体样品,进行了气体组分研究和碳同位素分析研究。研究表明,在试验区域,通过气体组分难以判断油气井是... 详细信息

为了研究煤矿工作面附近油气井泄漏情况,采用对比分析法,在煤矿工作面附近的油气井、井下工作面附近巷道和采空区中采集了一定量的气体样品,进行了气体组分研究和碳同位素分析研究。研究表明,在试验区域,通过气体组分难以判断油气井是否向煤矿工作面发生泄漏;甲烷碳同位素值测定方法为临近煤矿工作面的油气井泄漏监测的有效技术。

关键词：油气井泄漏监测技术煤矿工作面甲烷碳同位素值气体组分测定

隧道穿越富水断层破碎带围岩变形分析及处治措施

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国防交通工程与技术 2025年第1期23卷 70-74页

作者：李慧中铁十八局集团第一工程有限公司河北涿州072750

隧道穿越富水断层破碎带时易发生涌水突泥、初支变形过大、开裂等工程事故,隧道施工难度大、风险高,严重影响了施工进度。以高黎贡山隧道为工程背景,通过现场监测研究了隧道拱顶变形破坏特征,主要表现为拱顶沉降和非对称变形。围岩破碎... 详细信息

隧道穿越富水断层破碎带时易发生涌水突泥、初支变形过大、开裂等工程事故,隧道施工难度大、风险高,严重影响了施工进度。以高黎贡山隧道为工程背景,通过现场监测研究了隧道拱顶变形破坏特征,主要表现为拱顶沉降和非对称变形。围岩破碎、强度低及丰富的地下水是隧道通过断层破碎带施工过程中隧道发生大范围破坏、涌水和塌方的主要原因。采用了塌方体处理、注浆加固及施工方法调整等方面一系列综合处理措施,围岩变形得到有效控制,处治措施有效。

关键词：隧道工程富水断层围岩变形拱顶沉降注浆加固支护参数

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

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Science China life Sciences 2025年

作者： Shan Lu Chenxi Cao Wenjia Zhang Jiayi li Jingli Yang Zisheng Huang Zhijun Wu Baitao liu Hongjie Huang Haijun Wang Yongjian Wang Dingge liu Zhihua Zhang Kaiping liu Gang Yang Xi Gong hui Dai Yingjia li Erdan Dong Xin Zhang Yan Zhang Haihe Laboratory of Cell Ecosystem Institute of Cardiovascular Diseases The First Affiliated Hospital of Dalian Medical University Institute of Cardiovascular Sciences School of Basic Medical Sciences Peking University Health Science Center Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalState Key Laboratory of Vascular Homeostasis and Remodeling Peking University Department of Sports Medicine Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing Key Laboratory of Sports Injuries Engineering Research Center of Sports Trauma Treatment Technology and Devices Ministry of Education State Key Laboratory of Membrane Biology Institute of Molecular Medicine College of Future Technology Peking University Peking University Health Science Centre Peking University Department of Immunology School of Basic Medical Sciences NHC Key Laboratory of Medical Immunology Peking University Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital (Qingdao Municipal Hospital) School of Health and Life Sciences University of Health and Rehabilitation Sciences Research Unit of Medical Science Research Management/Basic and Clinical Research of Metabolic Cardiovascular Diseases Chinese Academy of Medical Sciences

Diffuse-type tenosynovial giant cell tumor(dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase(JAK)/signal transducer and activator of transcription(STAT) signaling plays a central role in rheumatoid arthritis(RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains *** fibroblast-like synoviocytes(FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS(both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and *** potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2(TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT(especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

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劳动力返乡创业对县域新型城镇化的影响

山西财经大学学报 2025年第1期47卷 16-30页

作者：魏滨辉罗明忠赵纯凯华南农业大学经济管理学院广州市新型智库重点基地乡村振兴研究中心

采用2010—2021年1 921个县域的面板数据，以返乡创业试点政策为准自然实验设计，探讨劳动力返乡创业对县域新型城镇化的实际影响及其作用机制。结果表明，返乡创业试点政策能显著推动县域新型城镇化建设，且该政策效应显示出良好的持... 详细信息

采用2010—2021年1 921个县域的面板数据，以返乡创业试点政策为准自然实验设计，探讨劳动力返乡创业对县域新型城镇化的实际影响及其作用机制。结果表明，返乡创业试点政策能显著推动县域新型城镇化建设，且该政策效应显示出良好的持续性。机制检验发现，基于内生增长理论视角，外出劳动力返乡创业通过促进产业结构升级与消费市场扩大来提高县域新型城镇化发展水平。异质性分析显示，返乡创业活动在制造业、房地产业等关键行业以及在宗族文化浓厚、初始劳动抚养比较高和平均受教育年限较低的地区，对县域新型城镇化建设具有更为明显的推动作用。

关键词：劳动力返乡创业县域新型城镇化产业结构升级消费市场扩大关键行业宗族文化初始人口特征技术进步

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局部晚期乳腺癌新辅助化疗的5年疗效分析

四川医学 2008年第7期29卷 836-837页

作者：付彬玉李卉陶苹谢旭林程娜四川省肿瘤医院放化疗科乳腺科四川成都610041

目的探讨局部晚期乳腺癌新辅助化疗后的远期临床疗效。方法回顾性分析了30例(A组)Ⅲa、Ⅲb期患者采用ECF方案新辅助化疗后的5年生存率(OS),无病生存率(DFS)及无病生存期。ECF方案具体为E-ADM70mg/m2第1天,CTX500mg/m2第1、8天,5-FU500mg... 详细信息

目的探讨局部晚期乳腺癌新辅助化疗后的远期临床疗效。方法回顾性分析了30例(A组)Ⅲa、Ⅲb期患者采用ECF方案新辅助化疗后的5年生存率(OS),无病生存率(DFS)及无病生存期。ECF方案具体为E-ADM70mg/m2第1天,CTX500mg/m2第1、8天,5-FU500mg/m2第18、天,每21d为1周期,术前化疗2周期,并与同期未行新辅助化疗的30例Ⅲa期患者(B组)进行比较。结果两组患者在5年OS、DFS及无病生存期方面比较,差异均无统计学意义(P>0.05);A组患者新辅助化疗的有效率为53.33%,80.0%的患者分期降低,16.67%的患者达到保乳手术要求。结论新辅助化疗可明显降低局部晚期乳腺癌患者的分期,显著地提高了对肿瘤局部的治疗效果;通过新辅助化疗可观察到肿瘤对化疗药物的敏感性;通过新辅助化疗后还可降低或延缓局部晚期乳腺癌患者的复发转移,提高了患者的生存质量,达到了最佳治疗效果。

关键词：局部晚期乳腺癌新辅助化疗