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An overview on metal-related catalysts: metal oxides, nanoporous metals and supported metal nanoparticles on metal organic frameworks and zeolites

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Rare Metals 2020年第7期39卷 751-766页

作者： Bhupendra Kumar Singh Sunwoo Lee Kyungsu na Department of Chemistry Chonnam National UniversityGwangju 61186Republic of Korea

Metal nanoparticles(NPs) supported on porous materials have shown great advantages in many catalytic application fields. Supported metal NPs are receiving extensive attention due to their significant contribution in a wide range of current and future applications, and this is arguably one of the fastest growing research fields. In this review, we highlight various types of metal catalysts that possess great potential in several catalytic reactions. The major focus has been on metal oxides, nanoporous metals and metal NPs supported on metal-organic frameworks(MOFs) and zeolites. Special attention has been given to the synthesis strategies and application of the NPs supported on MOFs and zeolites, which are considered highly interesting and rapidly expanding areas in heterogeneous catalysis. Finally, the prospects of these catalysts have been included in the concluding remarks.

关键词： Supported metal catalysts Porous materials nanoporous metals Heterogeneous catalysis Zeolites Metal oxides Metal-organic frameworks

Traditional Chinese Practice,A Promising Integrative Intervention for Chronic Non-Infectious Disease Management

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Chinese Journal of Integrative Medicine 2018年第12期24卷 886-890页

作者： WANG na GUO Yan Chinese PLA General Hospital Beijing(100853)China China Academy of Chinese Medical Sciences Beijing(100091)China

The number of people with chronic diseases rises rapidly in recent years worldwide. Except for drug medication, mind-body exercises are indispensable for chronic disease management. Traditional Chinese practice （TCP）, as an integrative intervention, is known as an effective means to keep in good health and fitness, as well as help regulate emotion. This paper introduces the domestic and overseas studies on effectiveness of TCP for chronic diseases, and explores the key action links from three aspects, including functional training of multiple-joint guided by consciousness, relieving psychological risk factors, improving respiratory and digestive function, blood and lymph circulation through respiratory training, and regulation of nerve, metabolic, and immune system. Finally, the authors discussed how to integrate TCP in the chronic disease management, and put forward that the practice methods and evaluation standard should be assessed academically.

关键词： traditional Chinese practice tai chi Qigong chronic disease management mind-body exercise joint training respiratory training neural-metabolic regulation

Influence of Isotope on Shell Effects of Pre-scission Particle Evaporation

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Communications in Theoretical Physics 2005年第2X期44卷 343-346页

作者： YE Wei CHEN na Department of Physics Southeast University Nanjing 210096 China Department of Applied Mathematics Nanjing University of Finance & Economics Nanjing 210003 China

The shell effects on the particle evaporation prior to fission for three Pb isotopes, ^204Pb, ^208Pb, and ^212pb,as well as three Sn isotopes, ^128Sn, ^132Sn, and ^136Sn, are explored by a diffusion model. Calculations show that the magnitude of shell effects in the emission of particles changes with the neutron-to-proton ratio N/Z of these fissioning nuclei, and this change is affected significantly by the spin and excitation energy of the system. It is shown that high angular momentum enhances the dependence of shell effects on the N/Z while high excitation energy weakens such a dependence.

关键词： isotopic effect shell effect pre-scission particle emission Smoluchowski equation

Roles of Isospin in Evaporation Residue Cross Section as a Probe of Nuclear Dissipation

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Communications in Theoretical Physics 2008年第3期49卷 739-742页

作者： CHEN na YE Wei Department of Applied Mathematics Nnnjing University of Finance ＆ Economics Nnnjing 210046 China Department of Physics Southeast University Nanjing 210096 China

The influence of isospin on the excess of evaporation residue cross section over its standard statistical-model value for nuclei ^194pb, ^200Pb, and ^206pb is studied via a Langevin equation coupled with a statistical decay model. The magnitude of this excess for a low-isospin fissioning nucleus is shown to be larger and its dependence on the nuclear viscosity coefficient to be stronger than those of a high-isospin fissioning nucleus. These results suggest that to obtain a more accurate information of viscosity coefficient inside the saddle point by measuring evaporation residue cross sections, we had better choose those compound systems with small isospin.

关键词： evaporation residue cross section isospin effect nuclear dissipation Langevin equation

Role of N/Z in Pre-scission Neutrons as an Observable of Nuclear Friction

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Communications in Theoretical Physics 2009年第8期52卷 329-332页

作者： CHEN na YE Wei School of Applied Mathematics Nanjing University of Finance and Economics Nanjing 210046 China Department of Physics Southeast University Nanjing 210096 China

A dynamical Langevin model is employed to evaluate the excess of the neutron emission in the fission ofheavy nuclei ^(240)Cf,^(246)Cf,^(254)Cf,^(240)U relative to the standard statistical-model prediction at various saddle-to-scissionfriction *** is shown that when the neutron-to-proton ratio N/Z of the system increases,the sensitivityof the excess to the friction decreases substantially,and it almost disappears for ^(240)*** suggest that using thosecompound systems with low N/Z favors an accurate determination for the saddle-to-scission friction strength based onthe measurement of the pre-scission neutron multiplicity.

关键词： pre-scission neutron multiplicity N/Z effect nuclear friction Langevin model

基于无监督深度领域对抗适配的在线剩余寿命预测方法

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郑州大学学报（理学版） 2025年第1期57卷 81-87页

作者：刘可盈张艳娜毛文涛王纳河南师范大学计算机与信息工程学院河南新乡453007 智慧商务与物联网技术河南省工程实验室河南新乡453007

为解决未知工况下旋转设备在线剩余寿命(remaining useful life,RUL)预测时计算代价大和误差累积问题,提出一种基于无监督深度领域对抗适配的在线RUL预测方法。首先,利用离线退化数据和在线早期故障数据,构建深度领域对抗网络作为预训... 详细信息

为解决未知工况下旋转设备在线剩余寿命(remaining useful life,RUL)预测时计算代价大和误差累积问题,提出一种基于无监督深度领域对抗适配的在线RUL预测方法。首先,利用离线退化数据和在线早期故障数据,构建深度领域对抗网络作为预训练模型。其次,将在线贯序数据块输入预训练模型的回归预测器中重新领域适配,得到在线伪标签。最后,将预训练模型的结构和参数迁移到目标域模型,冻结目标域模型的部分参数,并利用在线数据块和伪标签对目标域模型剩余参数进行微调,实现在线数据的RUL动态预测。在IEEE PHM Challenge 2012轴承数据集上进行实验,结果表明,所提方法可以贯序、准确地预测在线轴承RUL值,为在线场景下的轴承RUL预测提供了一种实用化的解决方案。

关键词：剩余寿命预测迁移学习领域适配无监督学习在线学习

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Highly Cis-1,4 Selective Polymerization of Conjugated Dienes Catalyzed by ^-heterocyclic Carbene-ligated Neodymium Complexes

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Chinese Journal of Polymer Science 2020年第12期38卷 1305-1312页

作者： Shu Zhang na Wu Yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Neodymium complexes containing N heterocyclic carbene(NHC)ligands,NdCl5[1,3,R(NCH=)2C]-THF,(Nd1:R=2,6-Pr2C6H3,x=0;Nd2:R=2,6-Et2C6H3,x=1;Nd3:R=2.4,6-Me3C6H2,x=1)were synthesized and employed as precatalysts for the coordination polymerization of conjugated dienes(butadiene and isoprene).In combination with trisobutylaluminium(TIBA),Nd1 promoted butadiene polymerization to produce extremely high cis-1,4(up to 99.0%)polybutadienes with high molecular weight(Mw=250-780 kg·mol 1).The Nd1/TIBA catalytic system also exhibited both high catalytic activity and cis-1,4 selectivity(up to 97.8%)for isoprene *** catalytic activity,molecular weight and molecular weight distribution of resulting polydienes were directly influenced by Al/Nd molar ratio,aging method,and polymerization *** interestingly,the high cis-1,4 selectivity of the catalyst towards butadiene and isoprene kept almost unchanged under different reaction *** cis-1,4 polyisoprenes with high molecular weight(Mw=210-530 kg·mol 1)and narrow molecular weight distribution (Mw/Mn=1.9-2.7)as well as high cis-1.4 selectivity(-~97%)could be synthesized by using the aged Nd1/TIBA catalytic system in the presence of isoprene(100 equivalent to Nd)at low AlNd molar ratios of *** with low molecular weights(Mw=12-76 kg·mol-7)and narrow molecular weight distributions (Mw/Mn=1.7-2.6)were obtained by using Nd2 and Nd3 as precatalysts,indicating that the molecular weight of resulting polyisoprenes can be adjusted by changing the substitutes of ligand in Nd complex.

关键词： Neodymium complex N heterocydic carbene igand Coordination polymerization Cis-14 sletivity Aging method

Carbon nanomaterials： controlled growth and field-effect transistor biosensors

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Frontiers of Materials Science 2012年第1期6卷 26-46页

作者： Xiao-na WANG Ping-An HU Key Laboratory of Micro-systems and Micro-structures Manufacturing(Ministry of Education) Harbin Institute of TechnologyHarbin 150080China Micro/nano Technology Research Center Harbin Institute of TechnologyHarbin 150080China

Carbon nanostructures, including carbon nanotubes （CNTs） and gra- phene, have been studied extensively due to their special structures, excellent electrical properties and high chemical stability. With the development of nanotechnology and nanoscience, various methods have been developed to synthesize CNTs/graphene and to assemble them into microelectroniclsensor devices. In this review, we mainly demon- strate the latest progress in synthesis of CNTs and graphene and their applications in field-effect transistors （FETs） for biological sensors.

关键词： carbon nanotube (CNT) graphene preparation field-effect transistor(FET) biosensor

Sensibility to Changes of Vibrational Modes of Excited Electron： Sum Frequency Signals Versus Difference Frequency Signals

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Communications in Theoretical Physics 2011年第3期55卷 506-512页

作者： GU An-na LIANG Xian-Ting Department of Physics and Institute of Modern Physics Ningbo University Ningbo 315211 China

In this paper, we investigate a two electronic level system with vibrational modes coupled to a Brownian oscillator bath. The difference frequency generation （DFG） signals and sum frequency generation （SFG） signals are calculated. It is shown that, for the same model, the SFG signals are more sensitive than the DFG signals to the changes of the vibrational modes of the electronic two-level system. Because the SFG conversion efficiency can be improved by using the time-delay method, the findings in this paper predict that the SFG spectrum may probe the changes of the microstructure more effectively.

关键词： difference frequency signals sum frequency signals response functions susceptibility