检索结果-南通市图书馆

考虑场地效应的多点地震动作用下边坡永久位移分析

在线全文

学校读者我要写书评

暂无评论

岩土工程学报 2025年第1期47卷 65-75页

作者：宋健潘驭航陆朱汐姬建张飞高玉峰河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学土木与交通学院江苏南京210024

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土... 详细信息

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土条赋予不同的水平和竖向地震动时程,推导出一种考虑场地效应的圆弧和任意形状滑面的多点地震作用下边坡永久位移分析方法。通过与有限差分软件FLAC的数值模拟结果进行对比,验证了该方法能够合理考虑地震动的场地效应。通过研究不同分布形式的多点地震动及竖向地震动对边坡永久位移的影响,结果表明:场地效应引起的水平地震动放大以及多点地震动不同分布模式会导致整个滑体平均地震惯性力作用位置发生改变,从而影响地震作用下滑动体沿滑面的永久变形量,竖向地震动对边坡地震位移影响较小。将方法应用于Lexington土石坝震后变形案例分析,计算得到的坝坡地震永久位移与实际震后观测值相吻合,证明了考虑场地效应的重要性及本文方法的合理性。

关键词：地震边坡稳定性场地效应永久位移极限平衡条分法多点地震动

Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2025年第2期31卷 85-101页

作者： jun-Yi Zhan Jie Chen Jin-Zhong Yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing jian Wang Yong-Ping Mu Cell Biology Laboratory Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Institute of Liver Diseases Shanghai Academy of Chinese MedicineShanghai 201203China Clinical Key Laboratory of Traditional Chinese Medicine of Shanghai Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Key Laboratory of Liver and Kidney Disease of the Ministry of Education Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Gastroenterology and Hepatology Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032China Shanghai Institute of Liver Disease Fudan UniversityShanghai 200032China Evidence-Based Medicine Center Fudan UniversityShanghai 200032China Department of Gastrointestinal Endoscopy Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Department of Hepatology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China

BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and *** its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are *** To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal *** This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 *** least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic *** validation was performed with bootstrap *** assessed the discrimination,calibration and accuracy of the model,and performed patient risk *** Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)*** predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation ***,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both *** We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients.

关键词： Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis

Construction of axial and point chirality through Ni-catalyzed sila-cycloaddition reaction via desymmetrization and (dynamic) kinetic resolution

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2025年

作者： Hua-Jie Zhu Ming-Hao Shen Jia-Wei Si Wei-Ke Zhu Xiao-jun Fang Fei Ye jian Cao Zheng Xu Li-Wen Xu Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education and Key Laboratory of Organosilicon Material Technology of Zhejiang Province College of Material Chemistry and Chemical Engineering Hangzhou Normal University State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences

Recent developments in chirality chemistry have revealed remarkable instances of atropisomers featuring multiple chiral elements. Despite significant progress in the synthesis and application of atropisomers, developing a synthetic protocol for the simultaneous introduction of axial and point chirality is still a fascinating challenge. In this context, we present a convenient and versatile method for synthesizing novel atropisomers with axial and point chirality. This approach, based on a new reaction mechanism with nickel-controlled Si–C bond activation, facilitates the controllable migratory insertion of aldehydes into the Ni–C bond. We utilize multidimensional strategies of desymmetrization, kinetic resolution and dynamic kinetic resolution to complete enantioselective nickel-catalyzed ring expansion of benzosilacyclobutenes with aldehydes. The design of multidimensional kinetic resolution, desymmetrization, and dynamic resolution, features a straightforward catalytic system, mild reaction conditions, and broad functional group tolerances. Various axially chiral biaryl oxasilacycles bearing carbon-or siliconstereogenic centers are obtained with excellent diastereo-and enantio-selectivities(up to >20:1 dr and >99.9% ee) through the use of a chiral Ni complex with a large cavity-type 1,1,4,4-tetra-aryl-2,3-O-isopropylidene-L-threitol(TADDOL)-derived phosphoramidite ligand.

关键词：

Correlation between gut microbiota and tumor immune microenvironment:A bibliometric and visualized study

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Oncology 2025年第2期16卷 110-129页

作者： Zheng-jun Hu Hui-Rong Zhu Yong-Jie Jin pan Liu Xiao-Wei Yu Yu-Ren Zhang Department of Oncology Shanghai Jiading District Hospital of Traditional Chinese MedicineShanghai 200000China Department of Oncology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 200000China School of Chinese Medicine Anhui University of Traditional Chinese MedicineHefei 230000Anhui ProvinceChina

BACKGROUND In recent years,numerous reports have been published regarding the relationship between the gut microbiota and the tumor immune microenvironment(TIME).However,to date,no systematic study has been conducted on the relationship between gut microbiota and the TIME using bibliometric *** To describe the current global research status on the correlation between gut microbiota and the TIME,and to identify the most influential countries,research institutions,researchers,and research hotspots related to this *** We searched for all literature related to gut microbiota and TIME published from January 1,2014,to May 28,2024,in the Web of Science Core Collection *** then conducted a bibliometric analysis and created visual maps of the published literature on countries,institutions,authors,keywords,references,etc.,using CiteSpace(6.2R6),VOSviewer(1.6.20),and bibliometrics(based on R 4.3.2).RESULTS In total,491 documents were included,with a rapid increase in the number of publications starting in *** country with the highest number of publications was China,followed by the United *** has the highest number of citations in *** a centrality perspective,the United States has the highest influence in this *** institutions with the highest number of publications were Shanghai Jiao Tong University and Zhejiang ***,the institution with the most citations was the United States National Cancer *** authors,Professor Giorgio Trinchieri from the National Institutes of Health has the most local impact in this *** most cited author was Fan *** results of journal publications showed that the top three journals with the highest number of published papers were Frontiers in Immunology,Cancers,and Frontiers in *** three most frequently used keywords were gut microbiota,tumor microenvironment,and *** This study systematically elaborates on the research progress re

关键词： Gut microbiota Tumor immune microenvironment Bibliometric CiteSpace VOSviewer R-bibliometrics

酚氧基修饰的AlPS-PVPA固载手性Salen Mn(Ⅲ)催化剂的合成及催化烯烃不对称环氧化研究

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

化学学报 2017年第7期75卷 715-722页

作者：王一帆范益梅蹇君潘雨民赵亮敬雪平周圣家谌晓洪杜泉王玲吴小菊傅相锴西华大学理学院成都610039 西华大学建设与管理工程学院成都610039 西华大学电气与电子信息学院成都610039 西南大学化学化工学院重庆400715

以有机共聚物-无机杂化材料聚(苯乙烯-苯乙烯基膦酸)-磷酸铝(AlPS-PVPA)为载体,酚氧基为连接基团,轴向配位手性salen Mn(Ⅲ)制备了新型固载手性salen Mn(Ⅲ)催化剂,并运用FT-IR,UV-vis,XPS,SEM,TG,元素分析等手段对其进行了表征.以m-CPB... 详细信息

以有机共聚物-无机杂化材料聚(苯乙烯-苯乙烯基膦酸)-磷酸铝(AlPS-PVPA)为载体,酚氧基为连接基团,轴向配位手性salen Mn(Ⅲ)制备了新型固载手性salen Mn(Ⅲ)催化剂,并运用FT-IR,UV-vis,XPS,SEM,TG,元素分析等手段对其进行了表征.以m-CPBA为氧化剂,茚和α-甲基苯乙烯为底物,考察了催化剂对非功能化烯烃不对称环氧化反应的催化性能.结果表明,在相同的条件下,固载催化剂3a^3d在不加助催化剂NMO时显示出了优良的催化活性,其转化率和ee值均比添加了轴向配体NMO时有很大的提高(ee%,99.2 vs.45.9;conv%,98.6 vs.64.6),这种现象与大多数文献报道相反.此外,催化剂容易分离,且回收使用9次仍能保持较好的催化活性.

关键词：聚(苯乙烯-苯乙烯基膦酸)-磷酸铝酚氧基修饰 Salen Mn(Ⅲ) 非功能化烯烃不对称环氧化反应

在线全文

学校读者我要写书评

暂无评论

新型抗静电整理剂PEEJ的应用

染整技术 2005年第11期27卷 30-33页

作者：季媛潘建君蔡再生东华大学上海200051

讨论了浓度、焙烘温度、焙烘时间和pH值对新型抗静电剂PEEJ整理工艺的影响,通过正交实验确定了其最佳整理工艺。并与纯聚醚酯类抗静电剂PEE进行了比较。

关键词：聚醚酯抗静电剂涤纶 PEEJ

Multi-omics analysis and experimental verification reveal testicular fatty acid metabolism disorder in non-obstructive azoospermia

在线全文

学校读者我要写书评

暂无评论

Zoological Research 2025年第01期 177-192页

作者： Zhou Li Yi-jian Xiang Zhi-Chuan Zou Yu-Ming Feng Hui Wang Wei-Qing Chen Xie Ge Jin-Zhao Ma jun Jing Bing Yao Department of Reproductive Medicine Jinling Hospital Affiliated Hospital of Medical School Nanjing University State Key Laboratory of Reproductive Medicine and Offspring Health Nanjing Medicine University

Increasing evidence implicates disruptions in testicular fatty acid metabolism as a contributing factor in nonobstructive azoospermia(NOA), a severe form of male infertility. However, the precise mechanisms linking fatty acid metabolism to NOA pathogenesis have not yet been fully elucidated. Multi-omics analyses, including microarray analysis, single-cell RNA sequencing(scRNA-seq), and metabolomics, were utilized to investigate disruptions in fatty acid metabolism associated with NOA using data from public databases. Results identified ACSL6, ACSBG2, and OLAH as key genes linked to fatty acid metabolism dysregulation, suggesting their potential causative roles in NOA. A marked reduction in omega-3 polyunsaturated fatty acids, especially docosahexaenoic acid(DHA), was observed, potentially contributing to the pathological process of NOA. Sertoli cells in NOA patients exhibited apparent fatty acid metabolic dysfunction, with PPARG identified as a key transcription factor(TF) regulating this process. Functional analyses demonstrated that PPARG is crucial for maintaining blood-testis barrier(BTB) integrity and promoting spermatogenesis via regulation of fatty acid metabolism. These findings reveal the pivotal role of fatty acid metabolism in NOA and identify PPARG as a potential therapeutic target.

关键词：

快速热处理温度对Fe-0.16C-1.4Mn钢组织和性能的影响

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

材料热处理学报 2025年第2期46卷 190-203页

作者：赵甲正张俊李俊王健北京科技大学新材料技术研究院北京100083 宝山钢铁股份有限公司中央研究院上海201999

通过感应加热的方式,利用多功能退火模拟实验机对Fe-0.16C-1.4Mn低合金高强钢进行快速热处理。采用X射线衍射仪、扫描电镜、电子背散射衍射技术、电子探针和透射电镜等研究了不同温度退火(660~810℃)保温不同时间(1和30 s)对实验钢微观... 详细信息

通过感应加热的方式,利用多功能退火模拟实验机对Fe-0.16C-1.4Mn低合金高强钢进行快速热处理。采用X射线衍射仪、扫描电镜、电子背散射衍射技术、电子探针和透射电镜等研究了不同温度退火(660~810℃)保温不同时间(1和30 s)对实验钢微观组织和性能的影响。结果表明:退火温度会显著影响实验钢的微观组织和力学性能;提高退火温度,实验钢的组织发生了从冷轧带状组织到再结晶铁素体再到马氏体双相组织的转变,这一转变伴随着晶粒的细化和等轴化,会显著影响其力学性能;在690℃退火保温30 s的条件下,实验钢得到了高屈服强度(516 MPa)和高伸长率(21.1%)的优异结合,适合作为建筑用高强钢;而在750℃退火保温30 s的条件下,实验钢表现出低屈强比和高抗拉强度(964 MPa),伸长率为13.6%,适合作为汽车用双相钢;Fe-0.16C-1.4Mn钢在拉伸过程中发生了部分再结晶和双相组织塑性应变不相容现象,这会对裂纹产生方式造成影响,进而影响其伸长率。

关键词：快速热处理低合金高强钢微观组织力学性能再结晶塑性不相容

不确定微分代数系统的目标全息反馈鲁棒自适应控制

在线全文

学校读者我要写书评

暂无评论

控制与决策 2025年第02期40卷 635-644页

作者：覃建波李啸骢徐俊华周建阳南宁学院智能制造学院广西大学电气工程学院

针对含不确定因素的多输入多输出非线性微分代数系统,提出一种目标全息反馈鲁棒自适应控制方法(robust adaptive control with objective holographic feedbacks, RACOHF).该方法考虑到了系统模型参数的不确定性和外部扰动,同时将外部... 详细信息

针对含不确定因素的多输入多输出非线性微分代数系统,提出一种目标全息反馈鲁棒自适应控制方法(robust adaptive control with objective holographic feedbacks, RACOHF).该方法考虑到了系统模型参数的不确定性和外部扰动,同时将外部输入扰动视为模型不确定性参数的变化,在目标全息反馈控制方法的基础上,通过设计模型不确定性部分的自适应调节律,实现多目标的自适应跟踪控制.将该方法应用于中间再热式汽轮发电机组蒸汽调节阀和励磁的协调控制,结果表明,在系统部分参数不确定和存在外部扰动的情况下,所提出方法能确保发电机机端电压和有功功率等目标量在期望的工作点上运行而不发生静态偏移.与目标全息反馈非线性控制(nonlinear control with objective holographic feedbacks, NCOHF)相比,所提出的方法(RACOHF)能更好地协调系统的动、静态性能.

关键词：非线性微分代数系统目标全息反馈模型参数不确定性鲁棒自适应控制中间再热式汽轮发电机组蒸汽调节阀和励磁协调控制