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Transfer film effects induced by 3D-printed polyether-ether-ketone with excellent tribological properties for joint prosthesis
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作者 Yang Li Jibao Zheng +1 位作者 Changning Sun Dichen Li 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第1期43-56,共14页
Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis ... Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis using fused filament fabrication and investigated the effects of printing orientation on its tribological properties using a pin-on-plate tribometer in 25% newborn calf serum.An ultrahigh molecular weight polyethylene transfer film is formed on the surface of PEEK due to the mechanical capture of wear debris by the 3D-printed groove morphology,which is significantly impacted by the printing orientation of PEEK.When the printing orientation was parallel to the sliding direction of friction,the number and size of the transfer film increased due to higher steady stress.This transfer film protected the matrix and reduced the friction coefficient and wear rate of friction pairs by 39.13%and 74.33%,respectively.Furthermore,our findings provide a novel perspective regarding the role of printing orientation in designing knee prostheses,facilitating its practical applications. 展开更多
关键词 3d printing orientation Transfer film Tribological properties Polyether-ether-ketone Knee prosthesis
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Mass Transfer-Promoted Fe^(2+)/Fe^(3+)Circulation Steered by 3D Flow-Through Co-Catalyst System Toward Sustainable Advanced Oxidation Processes
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作者 Weiyang Lv Hao Li +6 位作者 Jinhui Wang Lixin Wang Zenglong Wu Yuge Wang Wenkai Song Wenkai Cheng Yuyuan Yao 《Engineering》 SCIE EI CAS CSCD 2024年第5期264-275,共12页
Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-c... Realizing fast and continuous generation of reactive oxygen species(ROSs)via iron-based advanced oxidation processes(AOPs)is significant in the environmental and biological fields.However,current AOPs assisted by co-catalysts still suffer from the poor mass/electron transfer and non-durable promotion effect,giving rise to the sluggish Fe^(2+)/Fe^(3+)cycle and low dynamic concentration of Fe^(2+)for ROS production.Herein,we present a three-dimensional(3D)macroscale co-catalyst functionalized with molybdenum disulfide(MoS_(2))to achieve ultra-efficient Fe^(2+)regeneration(equilibrium Fe^(2+)ratio of 82.4%)and remarkable stability(more than 20 cycles)via a circulating flow-through process.Unlike the conventional batch-type reactor,experiments and computational fluid dynamics simulations demonstrate that the optimal utilization of the 3D active area under the flow-through mode,initiated by the convectionenhanced mass/charge transfer for Fe^(2+)reduction and then strengthened by MoS_(2)-induced flow rotation for sufficient reactant mixing,is crucial for oxidant activation and subsequent ROS generation.Strikingly,the flow-through co-catalytic system with superwetting capabilities can even tackle the intricate oily wastewater stabilized by different surfactants without the loss of pollutant degradation efficiency.Our findings highlight an innovative co-catalyst system design to expand the applicability of AOPs based technology,especially in large-scale complex wastewater treatment. 展开更多
关键词 Advanced oxidation processes 3d co-catalyst Flow-through mode Enhanced mass transfer Complex wastewater treatment
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Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions
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作者 Yi-Ping Xu Si-Lu Chen Dan-Yang Pang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期134-144,共11页
The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-b... The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave approximation.The target nuclei included both stable and unstable nuclei,and the incident energies reached 200 MeV.The results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 potential.Overall,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive targets.On average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 MeV.However,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca. 展开更多
关键词 Microscopic optical model potential (p d)transfer Spectroscopic factors
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Automatic detection of breast lesions in automated 3D breast ultrasound with cross-organ transfer learning
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作者 Lingyun BAO Zhengrui HUANG +7 位作者 Zehui LIN Yue SUN Hui CHEN You LI Zhang LI Xiaochen YUAN Lin XU Tao TAN 《虚拟现实与智能硬件(中英文)》 EI 2024年第3期239-251,共13页
Background Deep convolutional neural networks have garnered considerable attention in numerous machine learning applications,particularly in visual recognition tasks such as image and video analyses.There is a growing... Background Deep convolutional neural networks have garnered considerable attention in numerous machine learning applications,particularly in visual recognition tasks such as image and video analyses.There is a growing interest in applying this technology to diverse applications in medical image analysis.Automated three dimensional Breast Ultrasound is a vital tool for detecting breast cancer,and computer-assisted diagnosis software,developed based on deep learning,can effectively assist radiologists in diagnosis.However,the network model is prone to overfitting during training,owing to challenges such as insufficient training data.This study attempts to solve the problem caused by small datasets and improve model detection performance.Methods We propose a breast cancer detection framework based on deep learning(a transfer learning method based on cross-organ cancer detection)and a contrastive learning method based on breast imaging reporting and data systems(BI-RADS).Results When using cross organ transfer learning and BIRADS based contrastive learning,the average sensitivity of the model increased by a maximum of 16.05%.Conclusion Our experiments have demonstrated that the parameters and experiences of cross-organ cancer detection can be mutually referenced,and contrastive learning method based on BI-RADS can improve the detection performance of the model. 展开更多
关键词 Breast ultrasound Automated 3d breast ultrasound Breast cancers deep learning Transfer learning Convolutional neural networks Computer-aided diagnosis Cross organ learning
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D-二聚体与纤维蛋白原比值与不孕症患者IVF-ET助孕结局的相关性研究
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作者 韦霁芸 班婷 +3 位作者 石德敏 韦青妙 韦俏艺 韦兰静 《河北医科大学学报》 CAS 2024年第12期1409-1414,共6页
目的分析D-二聚体与纤维蛋白原比值(D-dimer/fibrinogen ratio,DFR)与不孕症患者体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)助孕结局的关系,为改善患者助孕结局提供经验。方法回顾性分析河池市人民医院生... 目的分析D-二聚体与纤维蛋白原比值(D-dimer/fibrinogen ratio,DFR)与不孕症患者体外受精-胚胎移植(in vitro fertilization and embryo transfer,IVF-ET)助孕结局的关系,为改善患者助孕结局提供经验。方法回顾性分析河池市人民医院生殖医学中心接受IVF-ET治疗的不孕症患者152例的病历资料,根据助孕结局进行分组,将获得临床妊娠的不孕症患者93例纳入妊娠成功组,妊娠失败组59例。收集2组人绒毛膜促性腺激素(human chorionic gon-adotrophin,HCG)注射日清晨D-二聚体、纤维蛋白原水平并计算二者比值DFR,分析DFR与不孕症患者IVF-ET助孕结局的相关性。结果妊娠失败组D-二聚体、纤维蛋白原及DFR值高于妊娠成功组,凝血酶原时间、活化部分凝血活酶时间及凝血酶时间短于妊娠成功组,差异有统计学意义(P<0.05)。经Point-biserial相关性分析显示,DFR与不孕症患者IVFIVF-ET助孕结局呈正相关(r=0.776,P=0.030)。经Logistic回归分析显示,D-二聚体、纤维蛋白原及DFR升高是不孕症患者IVF-ET助孕失败的危险因素(OR>1,P<0.05),凝血酶原时间、活化部分凝血活酶时间及凝血酶时间延长是不孕症患者IVF-ET助孕失败的保护因素(OR<1,P<0.05)。绘制受试者工作特征曲线,结果显示D-二聚体、纤维蛋白原、DFR、凝血酶原时间、活化部分凝血活酶时间及凝血酶时间对不孕症患者IVF-ET助孕结局均有一定的预测价值,但DFR预测价值最佳。结论DFR与不孕症患者IVF-ET助孕结局有关,即DFR值升高可增加不孕症患者IVF-ET助孕失败风险,且DFR值能为不孕症患者IVF-ET助孕结局的预测提供重要价值。 展开更多
关键词 不育 女(雌)性 体外受精-胚胎移植 d-二聚体 纤维蛋白原
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Intermolecular Vibrational Energy Transfers in Melts and Solutions
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作者 沈宇能 蒋博 +5 位作者 葛传琦 邓罡华 陈海龙 杨学明 袁开军 郑俊荣 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第4期407-417,I0001,共12页
Resonant and nonresonant intermolecular vibrational energy transfers in Gdm- SCN/KSCN=1/1, GdmSCN/KS^13CN=1/1 and GdmSCN/KS^13C^15N=1/1 mixed crystals in melts and in aqueous solutions are studied with the two dimensi... Resonant and nonresonant intermolecular vibrational energy transfers in Gdm- SCN/KSCN=1/1, GdmSCN/KS^13CN=1/1 and GdmSCN/KS^13C^15N=1/1 mixed crystals in melts and in aqueous solutions are studied with the two dimensional infrared spectroscopy. The energy transfers in the samples are slower with a larger energy donor/acceptor gap, independent of the Raman spectra. The energy gap dependences of the nonresonant energy transfers cannot be described by the phonon compensation mechanism. Instead, the experi- mental energy gap dependences can be quantitatively described by the dephasing mechanism. Temperature dependences of resonant and nonresonant energy transfer rates in the melts are also consistent with the prediction of the dephasing mechanism. The series of results suggest that the dephasing mechanism can be dominant not only in solutions, but also in melts (pure liquids without solvents), only if the molecular motions (translations and rotations) are much faster than the nonresonant energy transfer processes. 展开更多
关键词 Vibrational energy transfers 2d IR Phonon compensation mechanism dephasing mechanism
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CFD investigation of effect of nanofluid filled Trombe wall on 3D convective heat transfer 被引量:3
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作者 ALBAQAWY Ghazy MESLOUB Abdelhakim KOLSI Lioua 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第11期3569-3579,共11页
A numerical investigation was carried out on the effect of carbon nanotube(CNT)-water-nanofluid-filled Trombe wall on heat transfer and fluid flow inside a 3 D typical room.Time depending governing equations are consi... A numerical investigation was carried out on the effect of carbon nanotube(CNT)-water-nanofluid-filled Trombe wall on heat transfer and fluid flow inside a 3 D typical room.Time depending governing equations are considered with applying hot temperature at the left surface(collector) of the Trombe wall.The left wall(glazing) of the room and a square part(window) at the right wall are considered at cold temperature.The effects of Rayleigh number and the nanofluid volume fractions and the Trombe wall height on the temperature field,flow structure and heat transfer rate,are studied.The results show that the addition of nanoparticles and the increase of the Trombe wall height,enhance the heat transfer considerably and affect the flow structure and the temperature field. 展开更多
关键词 Trombe wall CNT-nanofluid 3d natural convection CFd heat transfer
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Mass Transfer of Copper(Ⅱ) in Hollow Fiber Renewal Liquid Membrane with Different Carriers 被引量:4
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作者 张卫东 崔春花 杨彦强 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期346-350,共5页
The extraction ability of organophosphorus extractant D2EHPA(di-2-ethylhexyl phosphoric acid) and hydroximic extractant Lix984N are investigated by the extraction equilibrium experiments.Effects of carrier concen-trat... The extraction ability of organophosphorus extractant D2EHPA(di-2-ethylhexyl phosphoric acid) and hydroximic extractant Lix984N are investigated by the extraction equilibrium experiments.Effects of carrier concen-tration and organic/aqueous volume ratio on the mass transfer of hollow fiber renewal liquid membrane(HFRLM) are studied.Results show that,in the extracting process,kerosene and n-heptane are more suitable than methyl-isobutyl ketone,butylacetate and benzene as the diluents of D2EHPA or Lix984N.The favorable feed pH is 4.4 for D2EHPA and 2.6 for Lix984N.The mass transfer flux of HFRLM increases with carrier concentration and finally reaches a plateau.The mass transfer flux and the overall transfer coefficient increase with the organic/aqueous volume ratio,reach the maximum and then decrease. 展开更多
关键词 mass transfer copper(Ⅱ) di-2-ethylhexyl phosphoric acidd2EHPA) Lix984N CARRIER
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Numerical Investigation of Convective Heat Transfer and Friction in Solar Air Heater with Thin Ribs 被引量:1
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作者 Sanjay K.Sharma V.R.Kalamkar 《Computer Modeling in Engineering & Sciences》 SCIE EI 2018年第3期295-319,共25页
The three-dimensional numerical investigation of an incompressible flow through rib roughened solar air heater is carried out.A combination of thin transverse and truncated ribs is attached on the absorber plate to st... The three-dimensional numerical investigation of an incompressible flow through rib roughened solar air heater is carried out.A combination of thin transverse and truncated ribs is attached on the absorber plate to study its effect on the heat transfer and friction factor.The parameters in the form of Reynolds number(Re)of 4000-16000,relative roughness pitch(P/e)of 8-18 and relative roughness height(e/Dh)of 0.0366-0.055 is considered for the analysis.The CFD code ANSYS FLUENT is used to solve the governing equations of turbulent flow.The RNG k-εturbulence model is used to solve the transport equations with enhanced wall treatment,keeping the Y+<1.The maximum enhancement ratio of the Nusselt number and friction factor obtained is 1.91 and 3.61 respectively.The detailed investigation on average heat transfer,friction factor and flow structures have been discussed. 展开更多
关键词 CFd 3d heat transfer FRICTION FACTOR
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Study of 3-D Numerical Simulation for Gas Transfer in the Goaf of the Coal Mining 被引量:12
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作者 WU Zheng-yan JIANG Shu-guang HE Xin-jian WANG Lan-yun LIN Bai-quan 《Journal of China University of Mining and Technology》 EI 2007年第2期152-157,共6页
In order to simulate field distribution rules,mathematical models for 3-D air flows and gas transfer in the goaf of the coal mining are established,based on theories of permeability and dynamic dispersion through poro... In order to simulate field distribution rules,mathematical models for 3-D air flows and gas transfer in the goaf of the coal mining are established,based on theories of permeability and dynamic dispersion through porous media. A gas dispersion equation in a 3-D field is calculated by use of numerical method on a weighted upstream multi-element balance. Based on data of an example with a U type ventilation mode,surface charts of air pressure distribution and gas concentration are drawn by Graphtool software. Finally,a comparison between actually measured results in the model test and the numerical simulation results is made to proves the numerical implementation feasible. 展开更多
关键词 3d numerical simulation of gas transfer in the goaf air pressure distribution in the goaf weighted upstream multi-element balance numerical simulation method
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Conduction mechanism studies on electron transfer of disordered system 被引量:1
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作者 徐慧 宋祎璞 李新梅 《Journal of Central South University of Technology》 2002年第2期134-137,共4页
Using the negative eigenvalue theory and the infinite order perturbation theory, a new method was developed to solve the eigenvectors of disordered systems. The result shows that eigenvectors change from the extended ... Using the negative eigenvalue theory and the infinite order perturbation theory, a new method was developed to solve the eigenvectors of disordered systems. The result shows that eigenvectors change from the extended state to the localized state with the increase of the site points and the disordered degree of the system. When electric field is exerted, the electrons transfer from one localized state to another one. The conductivity is induced by the electron transfer. The authors derive the formula of electron conductivity and find the electron hops between localized states whose energies are close to each other, whereas localized positions differ from each other greatly. At low temperature the disordered system has the character of the negative differential dependence of resistivity and temperature. 展开更多
关键词 disordered system localized state electron transfer d.C. conductivity
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Research on Rapid Response Schematic Design for Flexible Transfer Line CAPP-Based
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作者 GAO Ju-hong 1, XU Yan-shen 2 (1. Department of Industrial Engineering, School of Management, Tianjin University, 2. Department of Mechanical Engineering, School of Management, Tianjin Univers ity, Tianjin 300072, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期174-175,共2页
To meet the market requirements for Flexible Transf er Line (FTL), which consists of modular NC machining tools of high quality and co st saving, the methodologies and technologies of client-oriented FTL rapid resp on... To meet the market requirements for Flexible Transf er Line (FTL), which consists of modular NC machining tools of high quality and co st saving, the methodologies and technologies of client-oriented FTL rapid resp onse schematic design CAPP-based, one of the key techniques, are presented in t his paper. In order to achieve this purpose, an integrated system for integrated design of CAD/CAPP/FTL with box-type parts is realized. In this paper, firstly the theory of the conceptual design of FTL based on CAPP is established and the software architecture is developed. The global-domain pr oduct model is put forward to meet with data representation. After the manufactu ring feature is analyzed and decomposed for machining operations, the feature-b ased part unified data model object-oriented is built. Secondly the knowledge- based CAPP system data model is established. The process planning unit model is formed by work element (WE), which is tool-cell based function abstraction meth od, and has unified layers with respect to designing and manufacturing. With WEs through dynamic response and simultaneous structure in process planning, the pr inciple solution for CAPP function system can be implemented. Lastly the mapping from process domain to module design domain is built. The unidirectional select ion process based on fuzzy matching technology is easily dealt with computer. Th e algorithm of decision with fuzzy synthetic evaluation method and technology is applied to estimate the feasibility of the results in local working procedure o f modular NC machine tools and make decision of designs in overall FTL, which co nsists of many different factors. The example shows that the rapid response desi gn in bidding-based FTL scheme design is realized. 展开更多
关键词 CAPP flexible transfer line product model rapi d response design
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Direct Electron Transfer Reactions of Glucose Oxidase and D-Amino Acid Oxidase at a Glassy Carbon Electrode in Organic Media
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作者 Wei Jianjun Qin Yiqin Liu Haiying(School of Chemistry and Chemical Engineering) Deng Jiaqi(Fudan University) 《Advances in Manufacturing》 SCIE CAS 1998年第1期80-83,共4页
Cyclic voltammetry is employed to demonstrate feasibility of direct electron transfer of glucose oxidase and D amino acid oxidase at a glassy carbon electrode in organic media. The reversible slight conformational ch... Cyclic voltammetry is employed to demonstrate feasibility of direct electron transfer of glucose oxidase and D amino acid oxidase at a glassy carbon electrode in organic media. The reversible slight conformational change of glucose oxidase is observed by changing 0.1 mol/L phosphate buffer to acetonitrile containing 10% v/v of water and 0.05 mol/L tetrabutyalammonium perchlorate, and vice versa. 展开更多
关键词 glucose oxidase d amino acid oxidase direct electron transfer
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Sediment transport following water transfer from Yangtze River to Taihu Basin 被引量:2
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作者 Zheng GONG Chang-kuan ZHANG +1 位作者 Cheng-biao ZUO Wei-deng WU 《Water Science and Engineering》 EI CAS 2011年第4期431-444,共14页
To meet the increasing :need of fresh water and to improve the water quality of Taihu Lake, water transfer from the Yangtze River was initiated in 2002. This study was performed to investigate the sediment distributi... To meet the increasing :need of fresh water and to improve the water quality of Taihu Lake, water transfer from the Yangtze River was initiated in 2002. This study was performed to investigate the sediment distribution along the river course following water transfer. A rainfall-runoff model was first built to calculate the runoff of the Taihu Basin in 2003. Then, the flow patterns of river networks were simulated using a one-dimensional river network hydrodynamic model. Based on the boundary conditions of the flow in tributaries of the Wangyu River and the water level in Taihu Lake, a one-dimensional hydrodynamic and sediment transport numerical model of the Wangyu River was built to analyze the influences of the inflow rate of the water transfer and the suspended sediment concentration (SSC) of inflow on the sediment transport. The results show that the water transfer inflow rate and SSC of inflow have significant effects on the sediment distribution. The higher the inflow rate or SSC of inflow is, the higher the SSC value is at certain cross-sections along the :river course of water transfer. Higher inflow rate and SSC of inflow contribute to higher sediment deposition per kilometer and sediment thickness. It is also concluded that a sharp decrease of the inflow velocity at the entrance of the Wangyu River on the river course of water transfer induces intense sedimentation at the cross-section near the Changshu hydro-junction. With an increasing distance from the Changshu hydro-junction, the sediment deposition and sedimentation thickness decrease gradually along the river course. 展开更多
关键词 Taihu Basin Taihu Lake river network water transfer rainfall-runoff model 1-d hydrodynamic numerical model cohesive sediment
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Hierarchical monolithic carbon with high transfer performance for hydrogen evolution reaction
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作者 Yazhang Lin Weijie Zhu Yunhua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期41-48,I0002,共9页
Electrocatalysis is an efficient green process for energy conversion.However,for gas-related electrocatalytic reaction,sluggish gas transport has inhibited significantly the promotion of electrocatalytic performances.... Electrocatalysis is an efficient green process for energy conversion.However,for gas-related electrocatalytic reaction,sluggish gas transport has inhibited significantly the promotion of electrocatalytic performances.Herein,hierarchical monolithic material 3 DPC-650 and 3 DPC-650@Ni/Ni(OH)_(2) were prepared by3 D printing polyethyleneimine cross-linking oxygenated carbon nanotube and following nickel electrodeposition.3 DPC-650 and 3 DPC-650@Ni/Ni(OH)_(2) have regular pore structure in consistence with3 D printing design and uniform dispersed elements.Amide bonds and carbon defects are presented on the surface of 3 DPC-650 and 3 DPC-650@Ni/Ni(OH)_(2) as well as uniformly distributed β-Ni(OH)_(2) on3 DPC-650@Ni/Ni(OH)_(2).3 DPC-650 and 3 DPC-650@Ni/Ni(OH)_(2) present lower overpotentials of 322 and160 mV for hydrogen evolution reaction in 1.0 M KOH at 50 mA cm^(-2),respectively.The ordered channel,high turnover frequency and electrochemically active surface area,hydrophilic and aerophobic properties result in the higher performance of 3 DPC-650 and 3 DPC-650@Ni/Ni(OH)_(2) than traditional supports(carbon paper,carbon cloth,and nickel foam) and electrocatalysts.This work provides an efficient pathway for design and preparation of the monolithic electrocatalyst and electrode used for electrochemical reactions where gas is involved. 展开更多
关键词 3d printing Hierarchical structure MONOLITH Mass transfer Charge transfer Hydrogen evolution reaction
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MoS_(2)/Si tunnel diodes based on comprehensive transfer technique
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作者 朱翊 吕红亮 +4 位作者 张玉明 贾紫骥 孙佳乐 吕智军 芦宾 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期106-112,共7页
Due to the pristine interface of the 2D/3D face-tunneling heterostructure with an ultra-sharp doping profile, the 2D/3D tunneling field-effect transistor(TFET) is considered as one of the most promising low-power devi... Due to the pristine interface of the 2D/3D face-tunneling heterostructure with an ultra-sharp doping profile, the 2D/3D tunneling field-effect transistor(TFET) is considered as one of the most promising low-power devices that can simultaneously obtain low off-state current(IOFF), high on-state current(ION) and steep subthreshold swing(SS). As a key element for the 2D/3D TFET, the intensive exploration of the tunnel diode based on the 2D/3D heterostructure is in urgent need.The transfer technique composed of the exfoliation and the release process is currently the most common approach to fabricating the 2D/3D heterostructures. However, the well-established transfer technique of the 2D materials is still unavailable.Only a small part of the irregular films can usually be obtained by mechanical exfoliation, while the choice of the chemical exfoliation may lead to the contamination of the 2D material films by the ions in the chemical etchants. Moreover, the deformation of the 2D material in the transfer process due to its soft nature also leads to the nonuniformity of the transferred film,which is one of the main reasons for the presence of the wrinkles and the stacks in the transferred film. Thus, the large-scale fabrication of the high-quality 2D/3D tunnel diodes is limited. In this article, a comprehensive transfer technique that can mend up the shortages mentioned above with the aid of the water and the thermal release tape(TRT) is proposed. Based on the method we proposed, the MoS_(2)/Si tunnel diode is experimentally demonstrated and the transferred monolayer MoS_(2) film with the relatively high crystal quality is confirmed by atomic force microscopy(AFM), scanning electron microscopy(SEM), and Raman characterizations. Besides, the prominent negative differential resistance(NDR) effect is observed at room temperature, which verifies the relatively high quality of the MoS_(2)/Si heterojunction. The bilayer MoS_(2)/Si tunnel diode is also experimentally fabricated by repeating the transfer process we proposed, followed by the specific analysis of the electrical characteristics. This study shows the advantages of the transfer technique we proposed and indicates the great application foreground of the fabricated 2D/3D heterostructure for ultralow-power tunneling devices. 展开更多
关键词 2d/3d heterostructure transfer technique tunnel diode MoS_(2)/Si
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Transition Dipole, Charge Transfer, and Electron-hole Coherence in Two-photon Absorption: Visualizations with Two Dimensional Site and Three Dimensional Cube Representations
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作者 Yuan-zuo Li Wen-qin Zhang +2 位作者 Xiao-hong Zhao Feng-cai Ma Mao-du Chen 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第5期529-534,I0002,共7页
The developed visualization methods of two dimensional (2D) site and three dimensional (3D) cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole... The developed visualization methods of two dimensional (2D) site and three dimensional (3D) cube representations have been performed to show the orientation of transition dipole, charge transfer, and electron-hole coherence in two-photon absorption (TPA). The 3D cube representations of transition density can reveal visually the orientation and strength of transition dipole moment, and charge different density show the orientation of charge transfer in TPA. The 2D site representation can reveal visually the electron-hole coherence in TPA. The combination of 2D site and 3D cube representations provide clearly inspect into the charge transfer process and the contribution of excited molecular segments for TPA. 展开更多
关键词 2d site and 3d cube representations Charge transfer Transition dipole Two-photon absorption
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真菌源水平转移的载脂蛋白D基因影响二斑叶螨的寿命与生殖
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作者 陈磊 余心悦 +5 位作者 郭丽雪 陈煜炜 邴孝利 胡琪琪 孙荆涛 洪晓月 《昆虫学报》 CAS CSCD 北大核心 2024年第11期1439-1450,共12页
【目的】载脂蛋白D(apolipoprotein D,ApoD)是一类参与代谢、组织发育、免疫和抗氧化等多项生物功能的胞外蛋白,是抗衰老和延长寿命的重要分子基础。本研究旨在解析ApoD基因在叶螨基因组中的复制与扩张程度及其系统发育,探讨多功能ApoD... 【目的】载脂蛋白D(apolipoprotein D,ApoD)是一类参与代谢、组织发育、免疫和抗氧化等多项生物功能的胞外蛋白,是抗衰老和延长寿命的重要分子基础。本研究旨在解析ApoD基因在叶螨基因组中的复制与扩张程度及其系统发育,探讨多功能ApoD基因对二斑叶螨Tetranychus urticae的寿命和生殖的影响。【方法】联合使用BLASTP,HMMER,TBLASTN和GEMOMA鉴定番茄刺皮瘿螨Aculops lycopersici、截形叶螨Tetranychus truncatus和二斑叶螨基因组中ApoD家族基因;采用最大似然法构建细菌、真菌、植物、哺乳动物、昆虫、瘿螨和叶螨的ApoD系统发育树;依据二斑叶螨在不同发育阶段(卵、若螨、1日龄雌成螨和5日龄雌成螨)和不同寄主植物(菜豆、拟南芥Arabidopsis thaliana、番茄、茄子、棉花和黄瓜)上若螨或成螨的ApoD家族基因表达谱,挑选出ApoDR2,ApoD9,ApoD17和ApoD244个基因,采用dsRNA浸泡法对新羽化的二斑叶螨雌成螨进行ApoDR2,ApoD9,ApoD17和ApoD24的RNAi,并检测10 d内的存活率和单雌日均产卵量。【结果】二斑叶螨基因组中鉴定到68个ApoD基因,近缘种截形叶螨有33个ApoD基因,番茄刺皮瘿螨仅有1个ApoD基因,叶螨科之外的生物普遍拥有1~10个ApoD基因。系统发育分析结果表明,叶螨的ApoD家族主要分为三大簇,分别与昆虫、瘿螨和真菌的脂质转运蛋白基因聚类;叶螨中剧烈扩张的ApoD支系与真菌ApoD基因存在多个特有的一致性位点,且最大似然树显示亲缘关系近。大部分ApoD基因在二斑叶螨若螨和成螨期高水平表达,在二斑叶螨取食不同寄主植物时呈现多样的表达调控模式。与对照相比,沉默ApoDR2和ApoD9对二斑叶螨的适合度无显著影响,沉默ApoD17和ApoD24显著降低了二斑叶螨10 d内存活率和单雌日均产卵量,其中沉默ApoD17对二斑叶螨的存活率和单雌日产卵量影响较大。【结论】推测真菌源水平转移后获得的ApoD基因在叶螨基因组中剧烈扩张,并且对二斑叶螨的寿命和生殖产生了不同程度的影响,但是其在叶螨中的多功能性有待进一步研究。 展开更多
关键词 二斑叶螨 载脂蛋白d 水平转移 基因复制与扩张 寿命 生殖
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Scheme for realizing quantum computation and quantum information transfer with superconducting qubits coupling to a 1D transmission line resonator
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作者 施振刚 谌雄文 +1 位作者 朱喜香 宋克慧 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第3期910-914,共5页
This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on de-SQUID charge qubits through the control of their coupling to a 1D transmission lin... This paper proposes a simple scheme for realizing one-qubit and two-qubit quantum gates as well as multiqubit entanglement based on de-SQUID charge qubits through the control of their coupling to a 1D transmission line resonator (TLR). The TLR behaves effectively as a quantum data-bus mode of a harmonic oscillator, which has several practical advantages including strong coupling strength, reproducibility, immunity to 1/f noise, and suppressed spontaneous emission. In this protocol, the data-bus does not need to stay adiabatically in its ground state, which results in not only fast quantum operation, hut also high-fidelity quantum information processing. Also, it elaborates the transfer process with the 1D transmission line. 展开更多
关键词 dc-SQUId charge qubits 1d transmission line resonator quantum logic gates quantum information transfer
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Charge Transfer Mechanism and Spatial Density Correlation of Electronic States of Excited Zinc (3d<sup>9</sup>) Films
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作者 Li Chen Mitsugi Hamasaki +1 位作者 Hirotaka Manaka Kozo Obara 《Open Journal of Physical Chemistry》 2014年第2期44-51,共8页
In material science, half filled 3d orbital of transition metals is essentially an important factor controlling characteristics of alloys and compounds. This paper presents a result of the challenge of excitation of i... In material science, half filled 3d orbital of transition metals is essentially an important factor controlling characteristics of alloys and compounds. This paper presents a result of the challenge of excitation of inner-core electron system with long lifetime of zinc films. The advanced zinc films with excited inner-core electron, 3dn (n = 9, 8). We report experimental results of XPS measurements of 9 points in the sample along vertical direction, respectively. The most pronounced futures are existence of satellites, which are about 4 eV higher than the main lines. According to the charge transfer mechanism proposed by A. Kotani and K. Okada, it was clarified that the origins of these peaks are c3d9L for the main peak and c3d9 for the satellite, respectively. From the energy difference, δEB, and peak intensity ratio, I+/I-, between c3d9 and c3d10L, the energy for charge transfer, Δ, and mixing energy, T, were estimated. In the region where the intensity of c3d10L becomes large, Δ becomes small, 1.2 Δdc = 5.5 eV and Udd = 5.5 eV. In the analysis along vertical direction, intensity profile of Zn3d9 showed odd functional symmetry and that of Zn3d10L showed even functional symmetry. Only the intensity profile of C1s (288 eV) showed the same spatial correlation with Zn3d9. In our experiment, the sample also showed high mobility of the constituting elements. These suggest that charge conservation in excited zinc atom suggests combination between Zn3d9 and C2-. 展开更多
关键词 XPS Zn3d9 Charge Transfer SPATIAL SYMMETRY of EXCITEd STATES
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