检索结果-南通市图书馆

The spin-one Duffin Kemmer Petiau equation in the presence of pseudo-harmonic oscillatory ring-shaped potential

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2013年第10期22卷 107-111页

作者： h.hassanabadi M.Kamali Physics Department Shahrood University of Technology

The Duffin-Kemmer-Petiau equation （DKP） is studied in the presence of a pseudo-harmonic oscillatory ring-shaped potential in （1 ＋ 3）-dimensional space-time for spin-one particles. The exact energy eigenvalues and... 详细信息

关键词： DKP equation pseudo-harmonic oscillatory ring-shaped potential Nikiforov-Uvarov method en-ergy eigenvalues eigenfunctions

Study of the Geometry and Folding Pattern of Leaves of Mimosa pudica

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2007年第1期4卷 19-23页

作者： h. S. Patil Siddharth Vaijapurkar Department of Applied Mechanics S.V. National Institute of Technology Ichchanath Surat Gujarath 395007 India

Many structural and functional properties possessed by plants have great potentials to stimulate new concepts and innovative ideas in the field of biomimetic engineering. The key inputs from biology can be used for creation of efficient and optimized structures. The study of the geometry and folding pattern of leaves of Mimosa pudica, referred as Sensitive Plant, reveals some of the peculiar characteristics during folding and unfolding. When the leaf is touched, it quickly folds its leaflets and pinnae and droops downward at the petiole attachment. With the help of experiments on simulation model, the variations in angle of leaflets and degree of compaction after folding are investigated.

关键词： bionics biomimetics folding geometry leaves Mimosa pudica

DFT investigation of half-metallic ferromagnetic rare earth based spinels Mgho_(2)Z_(4)(Z=S,Se)

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第1期42卷 121-128,I0005页

作者： Maiza Zanib Mumtaz Manzoor N.A.Noor M.Waqas iqbal Mazia Asghar h.h.hegazy A.Laref Department of Physics Riphah International UniversityLahore CampusPakistan Research Centre for Advanced Materials Science King Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics Faculty of ScienceKing Khalid UniversityP.O.Box 9004AbhaSaudi Arabia Department of Physics and Astronomy College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia

half-metallic ferromagnetism,mechanical as well as thermoelectric properties for rare earth-based spinels Mgho_(2)Z_(4)(Z=S,Se)were investigated using density functional theory(DFT).Structural optimization was done with Perdew-Burke-Ehrenzorf(PBE)sol-generalized gradient approximation(GGA)to calculate the lattice constant of both spinels comparable to experimental *** addition,Born stability criteria and negative formation energy show that our studied spinels are also structurally and dynamically stable in the cubic *** ferromagnetic(FM)state stability,we also calculated the energy differences among FM,antiferromagnetic(AFM),and non-magnetic(NM)***,Curie temperatures of ferromagnetic phases were also *** used Trans-Blaha improved BeckeJohnson(TB-mBJ)potential functional for electronics as well as magnetic characteristics,which lead to the consistent explanation of half-metallic ferromagnetism,representing the whole band-occupancy in material with exact detail of density of states(DOS).The stable FM state was examined in spinels due to the exchange splitting of ho cation consisting of p-d hybridizations compatible with the result achieved for electronics band structure and ***,spin magnetic moment was explained in terms of anion,cation,and sharing charge on studied *** addition,the calculated thermoelectric properties clearly show that operation range of these systems may be utilized by future experimental works for identifying the potential applications of these systems.

关键词： ho-based spinels DFT simulations Mechanical parameters Electronic properties hM ferromagnetism Figure of merit

TiZr-base Bulk Metallic Glass with over 50 mm in Diameter

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第6期26卷 481-486页

作者： M. Q. Tang h.F. Zhang Z. W. Zhu h.M. Fu A.M. Wang h. Li Z.Q. hu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72Wenhua Road Shenyang 110016 China

Low-cost TiZr-base bulk metallic glasses （BMGs）（Ti36.1Zr33.2Ni5.8Be24.9）100-xCux （x=5, 7 and g） with a maximum size of over 50 mm in diameter were developed by optimizing the alloy composition. The idea is initiated by selecting a particular microstructure comprising primary β-Ti dendrite and amorphous phase. Afterwards, based on this composition of amorphous phase, a class of TiZr-base bulk metallic glasses was designed step by step to reach the optimum composition range. The glass transition temperature （Tg）, initial crystallization temperature （Tx） and width of supercooled region （AT） of （***33.2Nis.8Be24.9）91Cu9 BMG are 611, 055 and 44 K, respectively. The （Ti36.1Zr33.2Ni5.8Be24.9）91Cu9 BMG exhibits low density of 5.541 g·cm-3 and high compressive fracture strength of 1800 MPa, which promises the potential application as structural materials.

关键词： TiZr-base alloy Bulk metallic glass (BMG) Fracture strength

Use of virtual reality in underground roof fall hazard assessment and risk mitigation

在线全文

学校读者我要写书评

暂无评论

international Journal of Mining Science and Technology 2019年第4期29卷 603-607页

作者： E.isleyen h.S.Duzgun Department of Mining Engineering Colorado School of Mines

Virtual reality(VR)simulations are some of the alternative practice environments for safety *** gain experience under the most realistic conditions without being exposed to any real *** reality also serves as a tool to expedite the decision-making process where quick decisions and actions are necessities for a safe *** example of such a situation in underground mines is the failure risks in a tunnel face after *** support systems must be installed based on the stand-up time to ensure the safe access of personnel and equipment to the working ***,a competent person inspects the area to identify risks and determines the required support ***,training of a competent person requires large amount of time and *** study presents virtual reality simulations developed for improving the assessment of the roof fall hazards and taking necessary measures for mitigating the risk related to roof *** virtual reality simulation involves decision-making tasks for a particular scenario in which participants can experience creating a safe working environment in a timely ***,they are asked to identify the potential hazard in a tunnel after blasting,namely,rock fall,wedge failure or groundwater *** the hazard identification is successful,participants are requested to install rock bolts as a safety measure by selecting the bolt pattern(*** length and spacing).Finally,participants evaluate the roof fall hazard by viewing displacements around the opening,before and after the support *** study illustrates the benefits of VR in safety training as well as enhancing the decision-making process to enhance safety.

关键词： Virtual reality hazard assessment Tunneling

Thermal 9hot Noise through Boundary Roughness of Carbon Nanotube Quantum Dots

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2011年第1期28卷 186-189页

作者： Attia A. Awadalla Adel h. Phillips Department of Physics Faculty of Science Beni-Suef University Beni-Suef Egypt Department of Engineering Physics and Mathematics Faculty of Engineering Ain Shams University Cairo Egypt

Thermal shot noise, thermal voltage and thermo power are studied through a carbon nanotube quantum dot coupled to two leads with random roughness of amplitude on each of the two boundaries, under the effect of microwave field, and magnetic field. The expressions for the thermal shot noise and thermal energy are deduced when the barrier strength and contact area are taken into consideration. A model for such mesoscopic devices is proposed as a carbon nanotube quantum dot coupled to two leads with random roughness of amplitude on each of the two boundaries. The results show oscillatory behaviors of the dependence of the thermal shot noise on the studied parameters. The thermopower oscillates with the variation of the contact area, and the peak h.ights decrease linearly with the contact area and increases with temperature. This trend of behavior is due to the interplay of the induced microwave photons and the tunneling rate through the side bands. This research.is important for using a model as a high-frequency shot noise detector and the thermopower is sensitive to the energy dependence of the conductance.

关键词： Noise Energy Carbon Lead Carbonates Carbonation Models Boundaries Fields

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

30Ghz RF脉冲展宽器(英文)

高能物理与核物理 2003年第11期27卷 1027-1030页

作者：顾鹏达 i. Syratchev i. Wilson h.h. Braun S. Dbert W. Wuensch 中国科学院高能物理研究所北京100039 European Organization for Nuclear Research CH-1211 Geneva23 Switzerland

RF脉冲展宽器用来把高功率窄脉冲变换为较低功率的长脉冲,CLiC实验装置CTFⅡ中的功率提取结构已经可以提供功率达280MW,脉宽16ns的30Ghz RF脉冲,为了用它来研究加速结构的最高表面场强和脉宽的关系,设计了30Ghz RF脉冲展宽器,完成了系... 详细信息

RF脉冲展宽器用来把高功率窄脉冲变换为较低功率的长脉冲,CLiC实验装置CTFⅡ中的功率提取结构已经可以提供功率达280MW,脉宽16ns的30Ghz RF脉冲,为了用它来研究加速结构的最高表面场强和脉宽的关系,设计了30Ghz RF脉冲展宽器,完成了系统设计,微波部件的设计及加工,系统的调试,最后安装在CTFⅡ上,并成功进行了高功率实验。

关键词： RF脉冲展宽器加速结构设计 RF脉冲压缩器高功率微波脉冲直线对撞机 CTFⅡ装置

Observation of Rotational Bands in Neutron—Rich ^106Mo Nucleus

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2002年第2期19卷 180-183页

作者：许瑞清 J.h.hamilton DepartmentofPhysics TsinghuaUniversityBeijing100084 DepartmentofPhysics VanderbiltUniversityNashvilleTN37235USA

The rotational bands up to a spin of 16h.in the neutron-rich ^106Mo nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events following spontaneous fission of 252Cf with a Gammasphere detector array. The ground-state band, the one-phonon and two-phonon γ-vibrational bands, as well as a quasi-particle band have been confirmed and expanded. The other four collective rotational bands, three proposed as two-quasi-particle bands and one proposed as a β-vibrational band, have been newly observed. The characteristics of these collective bands and the possible configurations for the quasi-particle bands are discussed.

关键词： Gamma rays

Fragmentation of fuel pellets during transport via a belt conveyor:A design of experiment study

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

Particuology 2022年第7期20卷 29-37页

作者： hamid Gilvari Coen h.h.van Battum Richard Farnish Yusong Pang Wiebren de Jong Dingena L.Schott Section of Transport Engineering and Logistics Department of Maritime&Transport TechnologyFaculty of MechanicalMaritime and Materials EngineeringDelft University of TechnologyThe Netherlands Wolfson Centre for Bulk Solids handling Technology Faculty of Engineering&ScienceUniversity of GreenwichUnited Kingdom Section of Large Scale Energy Storage(LSE) Department of Process&EnergyFaculty of MechanicalMaritime and Materials EngineeringDelft University of TechnologyThe Netherlands

This work investigates the proportion of generated fines in a pilot-scale experiment using a belt conveyor and commercial fuel *** this,a belt conveyor with a length of 3.1 m was used and operated at varying conditions:speeds,percentages of material loading on the belt,two combinations of the inclination angle of the belt and the falling h.ight,and a different number of handling *** considered a design of experiments approach based on response surface methodology to investigate the effect of different conditions on the potential of fines ***,a comparison between the results of the belt conveyor and three common benchmark experimental approaches(tumbling box,rotary impact tester,and mechanical compression test)was *** show that the number of handling steps and the combined effect of drop h.ight and inclination angle directly affected the fines ***,the tested belt speed range and the level of loading were of lower significance.A polynomial quadratic model was derived based on the regression analysis and showed a high accuracy to predict the proportion of ***,the tumbling box method showed good potential to predict the proportion of fines in a belt conveyor when transported several times.

关键词： Fuel pellets Breakage Belt conveyor Transport Design of experiment Box–Behnken design