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电梯悬挂系统在建筑摇晃引起位移激励下横向振动分析

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振动与冲击 2013年第7期32卷 70-73页

作者：王文钱江同济大学结构工程与防灾研究所上海200092

以高层建筑在各种水平荷载作用下摇晃对高速运行电梯产生位移激励,引起电梯悬挂系统横向振动为研究对象,应用Hamilton原理建立电梯悬挂系统在建筑物摇晃引起两点位移激励下的横向振动偏微分方程,用Galerkin方法对运动方程进行离散化求... 详细信息

以高层建筑在各种水平荷载作用下摇晃对高速运行电梯产生位移激励,引起电梯悬挂系统横向振动为研究对象,应用Hamilton原理建立电梯悬挂系统在建筑物摇晃引起两点位移激励下的横向振动偏微分方程,用Galerkin方法对运动方程进行离散化求解。数值算例计算建筑物以不同频率摇晃时电梯悬挂系统横向振动响应;研究轿厢弹簧刚度、集中阻尼及绳索分布阻尼对系统振动影响。数值结果表明:当轿厢自振频率、绳索固有频率与建筑物摇晃引起的惯性力频率接近时,悬挂系统产生共振;通过改变弹簧刚度与阻尼系数,系统振动可得到不同程度抑制。

关键词：电梯悬挂系统建筑摇晃横向振动 Galerkin方法数值解

Development of wideband orthomode transducers for FAST cryogenic receiver system

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Research in Astronomy and Astrophysics 2020年第5期20卷 137-147页

作者： Jin Fan Kai Zhu Heng-qian Gan peng Jiang Jian Yang Yang Cao Hong-Fei Liu Hang Zhang Ming-Lei Guo Xiang-Wei Shi CAS Key Laboratory of FAST the National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Chalmers University of TechnologyGothenburgSweden

This paper describes the design,construction,and performance of the wideband orthomode transducers(OMTs)for the L-(1.2–1.8 GHz),the S-(2–3 GHz)and the P-(0.56–1.12 GHz)band receiver systems of the Five-hundred-meter Aperture Spherical radio Telescope(FAST).These OMTs operate at the cryogenic temperature of 70 K to reduce their thermal noise contribution to the receiver *** development on the FAST L-and S-band quad-ridged waveguide(QRWG)OMTs is carried out based on the theoretical mode *** view of the miniaturization of FAST cryogenic receiver system at P-band,a novel wideband compact bowtie dipole OMT is designed with an octave bandwidth as well as a length of only quarter *** proposed L-,S-and P-band OMTs are designed and optimized by using Ansys High Frequency Structure Simulator(HFSS),and then manufactured,tested at room *** of FAST cryogenic receiver system noise is also performed with the L-,S-and P-band OMTs *** measured results fully comply with the design specifications.

关键词： FAST instruments telescopes

血清微小RNA-1-3p、转录激活因子4在老年慢性心力衰竭患者中的表达水平及其与认知功能损伤的关系

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实用临床医药杂志 2024年第15期28卷 59-63页

作者：许文娟王会敏彭娟娥黄倩陈莉蔡烈松长江大学附属仙桃市第一人民医院老年病科湖北仙桃433000

目的探讨老年慢性心力衰竭(CHF)患者血清微小RNA-1-3p(miR-1-3p)、转录激活因子4(ATF4)的表达水平及其与认知功能损伤的关系。方法选取老年CHF患者150例为研究对象。根据蒙特利尔认知评估量表(MoCA)评分将患者分为认知功能损伤组(n=75)... 详细信息

目的探讨老年慢性心力衰竭(CHF)患者血清微小RNA-1-3p(miR-1-3p)、转录激活因子4(ATF4)的表达水平及其与认知功能损伤的关系。方法选取老年CHF患者150例为研究对象。根据蒙特利尔认知评估量表(MoCA)评分将患者分为认知功能损伤组(n=75)和认知功能正常组(n=75)。采用实时荧光定量聚合酶链反应(RT-qPCR)法检测2组血清miR-1-3p水平。采用酶联免疫吸附试验(ELISA)检测2组血清ATF4水平。采用Pearson相关性分析法分析老年CHF伴认知功能损伤患者血清miR-1-3p与ATF4水平的相关性。采用Logistic回归分析法分析老年CHF患者发生认知功能损伤的影响因素。采用受试者工作特征(ROC)曲线评估血清miR-1-3p、ATF4水平对CHF患者发生认知功能损伤的预测价值。结果认知功能损伤组的左心室射血分数(LVEF)、MoCA评分、血清miR-1-3p水平低于认知功能正常组,N末端脑钠肽前体(NT-proBNP)水平、血清ATF4水平高于认知功能正常组,差异有统计学意义(P<0.05)。老年CHF伴认知功能损伤患者血清miR-1-3p水平与血清ATF4水平呈负相关(r=-0.523,P<0.001)。miR-1-3p、ATF4是老年CHF患者发生认知功能损伤的影响因素(P<0.05)。血清miR-1-3p、ATF4联合预测老年CHF患者发生认知功能损伤的曲线下面积(AUC)大于血清miR-1-3p、ATF4单独预测的AUC,差异有统计学意义(P<0.05或P<0.001)。结论血清miR-1-3p表达水平与老年CHF患者认知功能呈正相关,血清ATF4表达与老年CHF患者认知功能呈负相关。血清miR-1-3p、ATF4可能是评估老年CHF患者认知功能损伤的潜在标志物。

关键词：老年慢性心力衰竭微小RNA-1-3p 转录激活因子4 认知功能

Temperature-dependent structure and magnetization of YCrO_(3)compound

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Chinese Physics B 2022年第4期31卷 493-499页

作者： qian Zhao Ying-Hao Zhu Si Wu Jun-Chao Xia peng-Fei Zhou Kai-Tong Sun Hai-Feng Li Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao SAR 999078China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Guangdong–Hong Kong–Macao Joint Laboratory for Neutron Scattering Science and Technology Dongguan 523803China

We have grown a YCrO_(3)single crystal by the floating-zone method and studied its temperature-dependent crystalline structure and magnetization by x-ray powder diffraction and PPMS DynaCool *** diffraction patterns were well indexed by an orthorhombic structure with space group of Pbnm(No.62).From 36 K to 300 K,no structural phase transition occurs in the pulverized YCrO_(3)single *** antiferromagnetic phase transition temperature was determined as T_(N)=141.58(5)K by the magnetization versus temperature *** found weak ferromagnetic behavior in the magnetic hysteresis loops below ***,we demonstrated that the antiferromagnetism and weak ferromagnetism appear simultaneously upon *** lattice parameters(a,b,c,and V)deviate downward from the Grüneisen law,displaying an anisotropic magnetostriction *** extracted temperature variation of the local distortion parameterΔ.Compared to theΔvalue of Cr ions,Y,O1,and O2 ions show one order of magnitude largerΔvalues indicative of much stronger local lattice ***,the calculated bond valence states of Y and O2 ions have obvious subduction charges.

关键词： orthochromates x-ray powder diffraction crystal structure magnetization

Lamb waves topological imaging combining with Green’s function retrieval theory to detect near filed defects in isotropic plates

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Chinese Physics B 2019年第7期28卷 286-292页

作者： Hui Zhang Hai-Yan Zhang Meng-Yun Xu Guo-peng Fan wen-Fa Zhu Xiao-Dong Chai Shanghai Institute for Advanced Communication and Data Science School of Communication and Information Engineering Shanghai University Shanghai 200444 China School of Urban Railway Transportation Shanghai University of Engineering Science Shanghai 201620 China

A method of combining Green’s function retrieval theory and ultrasonic array imaging using Lamb waves is presented to solve near filed defects in thin aluminum *** defects are close to the ultrasonic phased array and satisfy the near field calculation *** field acoustic information of defects is obscured by the nonlinear effects of initial wave signal in a directly acquired response using the full matrix capture mode.A reconstructed full matrix of inter-element responses is produced from cross-correlation of directly received ultrasonic signals between sensor *** new matrix eliminates the nonlinear interference and restores the near-field defect *** topological imaging method that was developed in recent ultrasonic inspection is used for displaying the *** experiments are conducted on both thin aluminum plates containing two and four defects, *** results show that these defects are clearly identified when using a reconstructed full *** spatial resolution is equal to about one wavelength of the selectively excited mode and the identifiable defect is about one fifth of the ***, in a conventional directly captured image,the images of defects overlap together and cannot be *** proposed method reduces the background noise and allows for effective topological imaging of near field defects.

关键词： Lamb waves topological imaging cross-correlation Green’s function

Access block and prolonged length of stay in the emergency department are associated with a higher patient mortality rate

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World Journal of Emergency Medicine 2022年第1期13卷 59-64页

作者： Ting Cheng qian peng Ya-qing Jin Hong-jie Yu Pei-song Zhong Wei-min Gu Xiao-shan Wang Yi-ming Lu Li Luo Department of Respiratory and Critical Care Medicine Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China Institute of Respiratory Diseases Shanghai Jiaotong University School of MedicineShanghai 200025China Shanghai Key Laboratory of Emergency Prevention Diagnosis and Treatment of Respiratory Infectious DiseasesShanghai 200025China School of Public Health Fudan UniversityShanghai 200032China Jiading District Center for Disease Control and Prevention Shanghai 201800China Department of Statistical Information Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 201801China Department of Emergency Ruijin HospitalShanghai Jiaotong University School of MedicineShanghai 200025China Key Laboratory of Public Health Safety of the Ministry of Education and Key Laboratory of Health Technology Assessment of the Ministry of Health Fudan UniversityShanghai 200032China

Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpatient unit within a reasonable time frame(no longer than 8 hours).[1,2]Access block often occurs due to insufficient hospital capacity and is a major issue in emergency medicine.[3]

关键词： Access admitted transferred

Analysis of alkaline phosphatase and γ-glutamyltransferase after radiofrequency ablation of primary liver cancer: A retrospective study

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World Journal of Gastrointestinal Surgery 2024年第9期16卷 2860-2869页

作者： wen-Yu Huang Sheng Zheng Dan Zhu Ying-Lang Zeng Juan Yang Xue-Li Zeng Pei Liu Shun-Ling Zhang Ming Yuan Zhi-Xia Wang Department of Tumor and Vascular Interventional Therapy Xiamen Humanity HospitalXiamen 361000Fujian ProvinceChina Department of Gastroenterology The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Medical Imaging Center Qian Wei Hospital of Jilin ProvinceChangchun 130000Jilin ProvinceChina Department of Science and Education The Third People's Hospital of Yunnan ProvinceKunming 650011Yunnan ProvinceChina Graduate School of Clinical Medicine Dali UniversityDali 671000Yunnan ProvinceChina Department of Hepatobiliary Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina Department of Oncology The Affiliated Shuyang Hospital of Xuzhou Medical UniversitySuqian 223600Jiangsu ProvinceChina

BACKGROUND Changes in alkaline phosphatase(ALP)andγ-glutamyltransferase(GGT)levels in patients with primary liver cancer(PLC)after radiofrequency ablation(RFA).Hepatocellular carcinoma is a malignant tumor with high incidence *** a common local treatment,RFA has attracted much attention for its efficacy and influence on liver *** To investigate the effect of serum ALP and GGT levels on the prognosis of patients with PLC treated by *** The preoperative clinical data of 165 patients who were pathologically or clinically diagnosed with PLC and who received RFA in our hospital between October 2018 and June 2023 were *** chi-square test was used to compare the data between *** Kaplan-Meier method and Cox regression were used to analyze the associ-ations between serum ALP and GGT levels and overall survival,progression-free survival(PFS)and clinical characteristics of patients before *** The 1-year survival rates of patients with normal(≤135 U/L)and abnormal(>135 U/L)serum ALP before treatment were 91%and 79%,respectively;the 2-year survival rates were 90%and 68%,respectively;and the 5-year survival rates were 35%and 18%,*** difference between the two groups was statistically significant(P=0.01).Before treatment,the 1-year survival rates of patients with normal serum GGT levels(≤45 U/L)and abnormal serum GGT levels(>45 U/L)were 95%and 87%,the 2-year survival rates were 85%and 71%,and the 5-year survival rates were 37%and 21%,*** difference between the two groups was statist-ically significant(P<0.001).Serum ALP[hazard ratio(HR)=1.766,95%confidence interval(95%CI):1.068-2.921,P=0.027]and GGT(HR=2.312,95%CI:1.367-3.912,P=0.002)is closely related to the overall survival of PLC patients after RF ablation and is an independent prognostic *** 1-year PFS rates were 72%and 50%,the 2-year PFS rates were 52%and 21%,and the 5-year PFS rates were 14%and 3%,*** difference between the

关键词： Alkaline phosphatase γ-glutamyltransferase Radiofrequency ablation Primary liver cancer Retrospective study

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樟树籽仁油的遗传毒性评价

中国油脂 2024年第8期49卷 75-81页

作者：彭婷梁丽军曾哲灵张淑虹鄢祥辉夏佳恒余平万冬满文学方南昌大学食品科学与资源挖掘全国重点实验室南昌330047 江西省药食同源植物资源高值化利用重点实验室南昌330031 南昌大学食品学院南昌330031 谱赛科(江西)生物技术有限公司江西赣州341108 南昌大学化学化工学院南昌330031 南昌大学资源与环境学院南昌330031 江西省科学院应用化学研究所南昌330096 中国中医科学院中医药健康产业研究所南昌330115

为评价樟树籽仁油的食用安全性,通过细菌回复突变试验、体外哺乳类细胞TK基因突变试验及哺乳动物红细胞微核试验探究樟树籽仁油的致突变和潜在致癌作用。结果表明:樟树籽仁油对组氨酸缺陷型鼠伤寒沙门氏菌TA1535、TA97、TA98、TA100、TA... 详细信息

为评价樟树籽仁油的食用安全性,通过细菌回复突变试验、体外哺乳类细胞TK基因突变试验及哺乳动物红细胞微核试验探究樟树籽仁油的致突变和潜在致癌作用。结果表明:樟树籽仁油对组氨酸缺陷型鼠伤寒沙门氏菌TA1535、TA97、TA98、TA100、TA102均无致突变作用;樟树籽仁油未抑制L5178Y小鼠淋巴瘤细胞的生长,对体外哺乳类细胞TK基因无致突变作用;樟树籽仁油未导致小鼠细胞微核率上升,对哺乳动物红细胞无致突变作用,无遗传毒性。综上,樟树籽仁油无细胞致突变和潜在致癌作用,没有遗传毒性,具有一定的食用安全性。

关键词：樟树籽仁油食用安全性遗传毒性

Synthesis and Immobilization of Polystyrene-b-Polyvinyltriethoxysilane Micelles

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 221-225页

作者：朱赛赛 ZHU Hui 夏茹 FENG Xiaoshuang CHEN peng qian Jiasheng CAO Ming YANG Bin MIAO Jibin SU Lifen SONG Changjiang Anhui Province Key Laboratory of Environment-friendly Polymer Materials School of Chemistry and Chemical Engineering Anhui University Division of Physical Sciences and Engineering King Abdullah University of Science and Technology(KAUST) Anhui Zhongyi Rubber Belts Co. Ltd

Diblock copolymers polystyrene-block-polyvinyltriethoxysilane（PS-b-PVTES） were synthesized via atom transfer radical polymerization（ATRP）, which self-assembled into spherical micelles in solvent of THF-methanol mixtures. The self-assembled micelles were immobilized by cross-linking reaction of VTES in a shell layer of micelles. The chemical structures of block copolymers and morphology of micelles were characterized in detail. It was found that the size of immobilized micelles was strongly affected by the copolymer concentration, composition of mixture solvent, and block ratios.

关键词： ATRP PS-b-PVTES self-assembly micelle immobilization