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Impact of prosthesis-patient mismatch on early and late outcomes after mitral valve replacement:a meta-analysis

Journal of Geriatric Cardiology 2020年第8期17卷 455-475页

作者： meng-Wei TAN Yi-fan BAI Xiao-Hong LIU zhi-Yun XU Zhao AN Ye MA Li-Bo ZHAO Bai-Ling LI Department of Cardiothoracic Surgery Changhai HospitalNaval Military Medical University(The Second Military Medical University)

Background Prognostic significance of prosthesis-patient mismatch(PPM)after mitral valve replacement(MVR)remains uncertain because of the limited studies reporting inconsistent or even contrary *** meta-analysis pooled results of all available studies comparing early and late prognoses between patients with significant mitral PPM and those *** Studies were identified by searching Pubmed,Excerpta Medica Database,Cochrane Central Register of Controlled Trials,and Clinical *** of PPM on postoperative hemodynamic results,thirty-day mortality,overall mortality,mortality of thirty-day survivors,and primary morbidity after MVR was evaluated via *** of pooled estimates,source of heterogeneity,and publication bias were assessed via sensitivity analyses,meta-regression as well as subgroup analysis stratified according to methodological or clinical heterogeneity,or sequential omission method,and funnel plot or Begg's and Egger's tests,*** Nineteen cohort studies involving 9302 individuals(PPM group:n=5109,Control group:n=4193)were included for *** PPM and severe PPM prevalence were 3.8%–85.9%and 1%–27%,with a mean value of 54.9%and 14.1%,*** compared with control group,mitral PPM group demonstrated a poorer postoperative hemodynamic status of higher mean and peak residual transprosthetic pressure gradients(TPG),higher postoperative systolic pulmonary artery pressure(SPAP)and less reduction,higher postoperative pulmonary hypertension(PH)prevalence and less PH regression,smaller net atrioventricular compliance,less NYHA class decrease,higher postoperative functional tricuspid regurgitation prevalence and less *** PPM group also revealed a higher thirty-day mortality,long-term overall mortality,mortality of thirty-day survivors,and postoperative congestive heart failure prevalence,which were positively correlated with the severity of PPM if it was classified into tri-le

关键词： Hemodynamics Meta-analysis Mitral valve replacement Morbidity Mortality Prosthesis-patient mismatch

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磷石膏/木质素固化铅污染土的无侧限抗压强度

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土木与环境工程学报（中英文） 2025年第1期47卷 89-99页

作者：赵之杨秀娟石庆红樊恒辉刘翼飞西北农林科技大学水利与建筑工程学院陕西杨凌712100 西北农林科技大学岩土工程研究所/特殊岩土博物馆陕西杨凌712100

采用工业固体废弃物磷石膏、木质素对人工配制铅污染土进行固化处理,通过无侧限抗压强度(UCS)试验探究固化剂掺量、养护龄期对不同程度铅污染土固化后应力-应变曲线、破坏形态及无侧限抗压强度的影响规律,对比分析两种固化剂的固化效果... 详细信息

采用工业固体废弃物磷石膏、木质素对人工配制铅污染土进行固化处理,通过无侧限抗压强度(UCS)试验探究固化剂掺量、养护龄期对不同程度铅污染土固化后应力-应变曲线、破坏形态及无侧限抗压强度的影响规律,对比分析两种固化剂的固化效果,并采用扫描电镜(SEM)试验分析土样固化前后的微观特性。试验结果表明,磷石膏、木质素均能增大固化土的无侧限抗压强度,减小破坏应变;固化土的无侧限抗压强度随磷石膏掺量增加呈持续上升趋势,随木质素掺量增加呈先上升后下降趋势;延长养护时间能有效提高固化土无侧限抗压强度。随固化剂掺量和养护龄期的增加,土体内部胶结水平提高,土样破坏形态从局部张裂逐渐转变为剪切破坏,呈现脆性破坏特征。两种固化剂固化土效果各有优劣,木质素对高浓度铅污染土的固化效果优于磷石膏,抵抗变形能力更好,而磷石膏短期内提升强度能力及对铅的固定效果更好。扫描电镜试验表明,固化剂可起到填充孔隙、胶结土颗粒的作用,水化产物在土体内形成致密结构,宏观表现为强度增强。

关键词：磷石膏木质素铅污染土无侧限抗压强度微观特性

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Deactivation Effect Caused by Catalyst-Cocatalyst Pre-contact in Propylene Polymerization with MgCl2-supported Ziegler-Natta Catalyst

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Chinese Journal of Polymer Science 2019年第10期37卷 1023-1030,I0005页

作者： Zhen Zhang Bai-Yu Jiang Biao Zhang zhi-Sheng Fu zhi-Qiang fan Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and Engineering Zhejiang University

Propylene slurry polymerization with a MgCl2-supported Ziegler-Natta catalyst containing internal electron donor was conducted after different durations of pre-contact of the catalyst with triethylaluminum cocatalyst. The number of active centers([C*]/[Ti])was determined by quenching the polymerization with 2-thiophenecarbonyl chloride and measuring sulfur content in the polymer. The pre-contact treatment caused selective deactivation of a part of active centers with low stereoselectivity and much lower activity in the initial stage of polymerization as compared with the polymerization run without the pre-contact stage. The active center concentration and polymerization activity decreased with prolonging of the pre-contact stage. The proportion of stereoselective active centers was increased by prolonging the pre-contact stage, so the isotacticity of produced polypropylene was enhanced. Release of active centers through catalyst particle fragmentation was significantly retarded, and the polymerization rate curve changed from decay type to induction type by the precontact treatment. In the induction period both non-stereoselective and stereoselective active centers were released and activated, resulting in gradual reduction of the polymer’s isotacticity in the first 5-10 min of polymerization. Selective deactivation of non-stereoselective active centers also took place in propylene polymerization using the catalyst without pre-contacting with the cocatalyst. In this case, the polymerization rate decayed with time after a short induction period of 2-5 min. Over reduction of the active center precursors with low stereoselectivity by triethylaluminum was considered as the reason for their deactivation during the pre-contact or the polymerization processes.

关键词： Propylene Polymerization Supported Ziegler-Natta catalyst Cocatalyst Pre-contact

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基于荧光光谱和拉曼光谱技术的中药检测研究

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光谱学与光谱分析 2025年第1期45卷 139-145页

作者：逯美红张凡暴雅婷王志军雷海英王翔宇高鹏慧长治学院物理系山西长治046011 西安信息职业大学物理实验中心陕西西安710125 长治学院生命科学系山西长治046011

中医药是中华文化的瑰宝和中华文明的结晶,在全民健康中发挥着重要作用。由于中药生长环境受限及市场需求量的增大,市场上出现了许多以次充好、以假乱真的中药,这对中药发展及质量保障都极为不利。因此,对中药的检测和鉴定非常重要。为... 详细信息

中医药是中华文化的瑰宝和中华文明的结晶,在全民健康中发挥着重要作用。由于中药生长环境受限及市场需求量的增大,市场上出现了许多以次充好、以假乱真的中药,这对中药发展及质量保障都极为不利。因此,对中药的检测和鉴定非常重要。为了探究中药的荧光光谱和拉曼光谱特性,选取白芷、苏木、山药、地榆四种中药进行分类检测研究。一方面,从化学成分和结构的角度分析中药白芷和苏木产生荧光的可能性,采用F-4600型荧光光谱仪(200~750 nm)分别在不同激发波长和不同浓度下测试了白芷和苏木水浸液的荧光光谱,探究了白芷和苏木水浸液的荧光光谱特性,并对荧光强度与不同浓度、激发波长的关系进行了探讨。另一方面,采用共聚焦显微拉曼光谱仪(100~4000 cm^(-1))对4种不同产地的山药和2种不同产地的地榆中药饮片的拉曼光谱分别进行测试研究。结果表明,白芷水浸液在波长260~350 nm的光激发下,产生较强荧光,最佳激发波长是340 nm,荧光峰值波长为420 nm,其荧光强度随浓度的增大而增强,且样品浓度较低时,荧光强度与浓度成线性关系;苏木水浸液在200~290 nm的光激发下,产生较强荧光,最佳激发波长为220 nm,荧光峰值波长为345 nm,随浓度的增加,荧光强度先增强后减弱,在浓度为0.175 mg·mL^(-1)时荧光强度达到最大。白芷水浸液和苏木水浸液的荧光强度都与激发波长的关系呈现高斯分布,符合荧光规律。分析山药和地榆的拉曼光谱,发现不同产地的拉曼特征基本一致,确认山药的拉曼特征峰主要集中在477、862、939、1080、1258、1337和1457 cm^(-1)处;地榆的拉曼特征峰主要集中在862和1337 cm^(-1)处,主要归属与已有的化学成分研究结果相符。部分特征峰处拉曼活性出现差异,可以作为区分不同产地中药的依据。该研究结果不仅为荧光光谱在中药鉴定及质量分析中的应用提供了实验数据和方法参考,也为利用拉曼光谱技术实现中药的快速准确检测及产地归属奠定了基础。

关键词：白芷苏木山药地榆荧光光谱拉曼光谱

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电感耦合等离子体发射光谱(ICP-OES)发展与应用

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中国无机分析化学 2025年第3期15卷 363-381页

作者：范博文黄秀高光晔袁姗姗邢志清华大学化学系北京100084 衡昇质谱(北京)仪器有限公司北京101318 河南省化工研究所有限责任公司郑州450052

电感耦合等离子体发射光谱(ICP-OES)商品化仪器问世已近50 a,已成为元素分析的重要工具,广泛应用于环境、材料、地质、冶金等各个领域。回顾ICP-OES仪器的发展历程,并针对ICP-OES的观测、降本增效、样品引入、降低干扰等技术以及对在环... 详细信息

电感耦合等离子体发射光谱(ICP-OES)商品化仪器问世已近50 a,已成为元素分析的重要工具,广泛应用于环境、材料、地质、冶金等各个领域。回顾ICP-OES仪器的发展历程,并针对ICP-OES的观测、降本增效、样品引入、降低干扰等技术以及对在环境、食品、地矿、金属、无机非金属、化学化工样品中的应用进行综述。近些年,激光诱导击穿光谱(LIBS)、微波等离子体发射光谱(MIP-AES)等其他一些分析方法相关研究逐渐增多,它们具有成本相对低、测试通量大等优势。然而,这些研究中有很大一部分方法研究最终仍通过ICP-OES进行验证,这充分说明ICP-OES分析结果的可靠性。未来,ICP-OES仍有很大提升空间,如仪器小型化、车载化、智能化等相关研究方向。

关键词：电感耦合等离子体发射光谱仪器发展技术发展元素分析

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Coherent interaction and action–counteraction theory in small polaron systems,and ground state properties

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Chinese Physics B 2022年第11期31卷 474-481页

作者： zhi-Hua Luo Chao-fan Yu School of Physics and Information Engineering Guangdong University of EducationGuangzhou 510303China

Based on the coherent interaction and action–counteraction principles,we investigate the ground state properties for small polaron systems,the coherent-squeezed fluctuation correction,and the anomalous lattice quantum fluctuation,with the new variational generator containing correlated squeezed-coherent coupling and quantum *** tha t-2t is the ***,for the coherent interaction effect,we find the ground-state energy E_(0)to be-2.428t,in which the coherent squeezed fluctuation correction-A_(0)t is-0.463t(where t is the hopping integral,ωis the phonon frequency),with the electron–one-phonon coupling constant g=1 and the electron–two-phonon coupling constant g_(1)=-***,as a result of the action–counteraction effect,E_(0)is-2.788t,but-E_(0)t *** to the polaron binding energy(EP),for the coherent interaction effect,E_(P) is-1.38ω,but for the action–counteraction effect,E_(P) is-1.88ω.In particular,the electron–two-phonon interaction noticeably enlarges the coherent interaction and the coherent squeezed quantum fluctuation *** intervening with the quantum entanglement,the evolutions of the squeezed coherent state and the lattice quantum fluctuation begin to take *** that time,we encounter a new quantum phase coherence phenomenon—the collapse and revival of inversion repeatedly for the coherent state in the entangled evolution.

关键词： coherent interaction and action-counteraction correlated representation variational approach entangled-squeezed coherent state interaction of electron with the coherent squeezed fluctuation

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单基发射药的药型对分子裁剪反应过程动力学的影响

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含能材料 2025年第1期33卷 47-56页

作者：彭智华王欣雨顾玉乐范红蕾李世影李纯志王晓倩肖忠良吴晓青中北大学化学与化工学院山西太原030051 南京理工大学化学与化工学院江苏南京210094 南京理工大学特种能源材料教育部重点实验室江苏南京210094 泸州北方化学工业有限公司四川泸州646003 驻太原地区防化军代室山西太原030000

为研究药型尺寸对单基发射药分子裁剪反应过程的影响,以水合肼为脱硝试剂,对七孔、单孔和无孔单基发射药进行表层分子裁剪,制备了3种梯度硝基单基发射药。基于Avrami模型对不同药型单基发射药分子裁剪反应过程的动力学进行了研究,结果表... 详细信息

为研究药型尺寸对单基发射药分子裁剪反应过程的影响,以水合肼为脱硝试剂,对七孔、单孔和无孔单基发射药进行表层分子裁剪,制备了3种梯度硝基单基发射药。基于Avrami模型对不同药型单基发射药分子裁剪反应过程的动力学进行了研究,结果表明:Avrami模型可以用于描述3种药型单基发射药的分子裁剪反应过程;七孔单基发射药的Avrami指数,在70~75℃范围内n>1,分子裁剪反应过程受化学反应过程控制;在75~80℃范围内n<1,分子裁剪反应过程受内扩散和化学反应共同控制。单孔和无孔单基发射药的Avrami指数n<1,分子裁剪反应过程受内扩散和化学反应共同控制。依据Fick定律求得单孔和无孔单基发射药的扩散系数D,单孔单基发射药的扩散系数为3.8×10^(-13)~10.2×10^(-13)m^(2)·s^(-1),无孔单基发射药的扩散系数为3.7×10^(-13)~5.1×10^(-13)m^(2)·s^(-1);利用Arrhenius方程计算出3种单基发射药的表观活化能,七孔、单孔和无孔单基发射药的表观活化能分别为45.84,52.88和38.26 kJ·mol^(-1)。研究通过对不同药型单基发射药分子裁剪反应过程动力学的研究,为梯度硝基单基发射药的可控制备提供理论指导。

关键词：梯度硝基单基发射药不同药型分子裁剪反应动力学 Avrami模型

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Cladding of aluminum alloy 6061-T6 to mild steel by an electromagnetic tube bulging process: finite element modeling

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Advances in Manufacturing 2019年第1期7卷 73-83页

作者： zhi-Song fan Su-Ting Huang Jiang-Hua Deng School of Mechanical Engineering and Automation Fuzhou University Fuzhou 350116 People's Republic of China

Bimetal tubes have useful applications in various industries where service conditions demand more different requirements in the tube core than its outside surface. The recent use of electromagnetic forces to deform or join metallic workpieces at high speeds has undergone rapid growth for materials processing. However, to date, no sufficient systematic understanding of the underlying principles of a subsequent high-speed electromagnetic tube bulging process to manufacture bimetal tubes has been gained. In this work, magnetic pulse cladding of Al/Fe clad bimetal tubes was analyzed by finite element modeling (FEM) using ANSYS software. The validity of FEM analyses was first confirmed by experiments in terms of the deformed shape. Second, the effect of cladding parameters (such as axial feeding being the dominant factor in the multi-step process) on the bulging and thinning behavior of the Al clad tube was presented in detail. Both the numerical simulation and experimental results show that no more than 70% of the bulging-coil length is an appropriate amount for the feeding length to prevent defects from being introduced by non-uniform deformation in the transition zone of the Al clad tube. The distributions of the magnetic flux line, magnetic force, and plastic strain in different cladding steps were then analyzed. It was concluded that during the multi-step cladding process, there was an uneven distribution of the magnetic field force along the transition zone. Consequently, inharmonious plastic deformation behavior occurs, which results in a limited acceleration of the transition zone to a certain impact velocity.

关键词： Bimetal tubes Magnetic pulse cladding Finite element (FE) simulation Axial feeding

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Overcome Debye Length Limitations for Biomolecule Sensing Based on Field Effective Transistors

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Chinese Journal of Chemistry 2021年第4期39卷 999-1008页

作者： zhi Zheng Hongyuan Zhang Tianyou Zhai fan Xia Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of GeosciencesWuhanHubei430074 China State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhanHubei 430074Chino

Biosensors based on field effective transistor(FET)have aroused tremendous attention in the past few years owning to their huge application in drug discovery,disease diagnosis and environmental *** FET biosensors possess small volume,high sensitivity at ultra-low concentration,considerable mechanical strength,as well as excellent stability in solution,which plays a vital role in the point of care testing(POCT)*** advances have summarized some progress involved in the improvement of morphology and structure of channel materials,the functionalization of organic molecule,the influence of device operation and sensing environment on the detecting ***,for FET biosensors,the charge screening phenomena were inevitable in the solution,which seriously degrade the device *** this article,we summarize recent advances to overcome debye length limitations for biomolecule sensing based on *** will firstly describe the charge screening mechanism,then focous on the strategy to overcome charge screening,including synthesizing special channel materials with crumpled morphology,designing aptamer binding mode,and modulating device ***,we discuss the major challenges and perspectives about overcoming debye length limitations of FET *** summaries provide further insights to realize real-time,lable-free,high-sensitivity FET sensors for medical healthcare.

关键词： Debye length Interactions Field effective transistors Biosensors Biomolecule

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A New Technique:Research and industrial application of a novel compound permanent magnet synchronous machine

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 471-477页

作者： Cheng-zhi fan Ming-xing HUANG Yun-yue YE School of Electrical Engineering Zhejiang University Hangzhou 310027 China

We propose a novel kind of compound permanent magnet synchronous machine (CPMSM), which is applicable in low-speed and high-torque situations. We first explain the structure of the CPMSM. Based on theoretically deducing the calculation formulae of the CPMSM electromagnetic parameters, we analyze the operating characteristics of the CPMSM, and obtain the power-angle curves and working curves. The no-load magnetic field distribution and the cogging torque are analyzed by applying the finite element method of three-dimensional (3D) magnetic fields, to determine the no-load leakage coefficient and the waveform of the cogging torque. Furthermore, the optimal parameters of the permanent magnet for reducing the cogging torque are determined. An important application target of the CPMSM is in directdrive pumping units. We have installed and tested a direct- drive pumping unit in an existing oil well. Test results show that the power consumption of the direct-drive pumping unit driven by CPMSM is 61.1% of that of the beam-pumping unit, and that the floor space and weight are only 50% of those of a beam-pumping unit. The noise output does not exceed 58 dB in a range of 1 m around the machine when the machine is 1.5 m from the ground.

关键词： Compound permanent magnet synchronous machine (CPMSM) Operating characteristic Three-dimensional finite element analysis Cogging torque Direct-drive pumping unit

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