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Effects on the Behavior and Neuroimmunity of Pulsed Microwaves with Different Peak Densities
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作者 YANG Zhen Zhong WU Da Wei +2 位作者 MA Hong Bo FEI Jin Xue ZHAO Ya Li 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第12期893-897,共5页
Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous ... Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous biological effects, including 展开更多
关键词 Effects on the Behavior and Neuroimmunity of Pulsed Microwaves with different Peak densities
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Porosity Evaluation and the Power Spectral Densities Analyses of Carbon-Nickel Composite Films Annealed at Different Temperatures
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作者 V.Dalouji S.M.Elahi +1 位作者 A.Ghaderi S.Solaymani 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期96-99,共4页
The densification and the fractal dimensions of carbon-nickel films annealed at different temperatures 300, 500, 800, and 1000℃ with emphasis on porosity evaluation are investigated. For this purpose, the refractive... The densification and the fractal dimensions of carbon-nickel films annealed at different temperatures 300, 500, 800, and 1000℃ with emphasis on porosity evaluation are investigated. For this purpose, the refractive index of films is determined from transmittance spectra. Three different regimes are identified, T 〈 500℃, 500℃ 〈 T 〈 800℃ and T 〉 800℃. The Rutherford baekscattering spectra show that with increasing the annealing temperature, the concentration of nickel atoms into films decreases. It is shown that the effect of annealing temperatures for increasing films densification at T 〈 500℃ and T 〉 800℃ is greater than the effect of nickel concentrations. It is observed that the effect of decreasing nickel atoms into films at 500℃ 〈 T 〈 800℃ strongly causes improving porosity and decreasing densification. The fractal dimensions of carbon-nickel films annealed from 300 to 500℃ are increased, while from 500 to 1000℃ these characteristics are decreased. It can be seen that at 800℃, films have maximum values of porosity and roughness. 展开更多
关键词 of on it Ni Porosity Evaluation and the Power Spectral densities Analyses of Carbon-Nickel Composite Films Annealed at different Temperatures is that into
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Simulation of random mixed packing of different density particles 被引量:1
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作者 李元元 夏伟 +3 位作者 周照耀 何克晶 钟文镇 吴苑标 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第2期336-341,共6页
This paper presents the effects of density difference on the three-dimensional (3D) distribution of random mixed packing. The random mixed packing dynamics of particles of two different densities are simulated. The ... This paper presents the effects of density difference on the three-dimensional (3D) distribution of random mixed packing. The random mixed packing dynamics of particles of two different densities are simulated. The initial state is homogeneous, but the final packing state is inhomogeneous. The segregation phenomenon (inhomogeneous distribution) is also observed. In the final state, the top layers are composed of mostly light particles. The several layers beneath the top contain more heavy particles than light particles. At the bottom, they also contain more heavy particles than light particles. Furthermore, at both the top and the bottom, particle clustering is observed. The current study also analyses the cause of this inhomogeneity in detail. The main cause of this phenomenon is the velocity difference after collision of these two types of particles induced by the density difference. The present study reveals that even if particles were perfectly mixed, the packing process would lead to the final inhomogeneous mixture. It suggests that special treatment may be required to get the true homogeneous packing. 展开更多
关键词 mixed packing different densities granular particle discrete element method simulation
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Improving the electrical performances of InSe transistors by interface engineering
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作者 曹天俊 郝松 +5 位作者 吴晨晨 潘晨 戴玉頔 程斌 梁世军 缪峰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期153-158,共6页
InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hinder... InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hindered due to its sensitivity to interfaces.In this study,we have achieved notable enhancement in the electrical performance of InSe transistors through interface engineering.We engineered an InSe/h-BN heterostructure,effectively suppressing dielectric layer-induced scattering.Additionally,we successfully established excellent metal-semiconductor contacts using graphene ribbons as a buffer layer.Through a methodical approach to interface engineering,our graphene/InSe/h-BN transistor demonstrates impressive on-state current,field-effect mobility,and on/off ratio at room temperature,reaching values as high as 1.1 mA/μm,904 cm^(2)·V^(-1)·s^(-1),and>10~6,respectively.Theoretical computations corroborate that the graphene/InSe heterostructure shows significant interlayer charge transfer and weak interlayer interaction,contributing to the enhanced performance of InSe transistors.This research offers a comprehensive strategy to elevate the electrical performance of InSe transistors,paving the way for their utilization in future electronic applications. 展开更多
关键词 two-dimensional materials INSE van der Waals heterostructure electrical performances charge density difference
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Theoretical Study of Pnicogen Bonding Interactions between ECl3(P, As) and Different Electron Donors
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作者 XU Hui-Ying WANG Wei +3 位作者 ZHU Jian-Qing ZOU Jian-Wei XU Xiao-Lu LU Yin 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第12期2027-2040,共14页
The pnicogen bond interaction between different electron donors(anion, π-electron, heteroatom) and ECl3(E = As, P) was calculated by the method of MP2/aug-cc-p VTZ. It has been indicated that the pnicogen bonds of co... The pnicogen bond interaction between different electron donors(anion, π-electron, heteroatom) and ECl3(E = As, P) was calculated by the method of MP2/aug-cc-p VTZ. It has been indicated that the pnicogen bonds of complex formed by the anion and ECl3 are more stable than that by the neutral electron donor, in which the pnicogen bonds of complex formed by NH3 and ECl3 are the most stable, and that by H2S and ECl3 is the least stable. The nature of pnicogen bond interaction is the closed shell interaction by AIM analysis, and BCP electron density is positively correlated to the complex interaction energy. RDG and DDF graphical analyses are performed to visualize the nature of pnicogen bond interaction from different donors, the position and strength of the pnicogen bond interaction, as well as the rearrangement of electron density after the formation of pnicogen bond system. 展开更多
关键词 pnicogen bonding hydrogen bonding AIM RDG analyses electronic density difference analyses
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Increasing photosynthetic performance and post-silking N uptake by moderate decreasing leaf source of maize under high planting density 被引量:13
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作者 CAO Yu-jun WANG Li-chun +2 位作者 GU Wan-rong WANG Yong-jun ZHANG Jun-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第2期494-510,共17页
To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year fi... To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year field experiment,Xianyu 335,a widely released hybrid in China,was planted at 60 000 plants ha^(–1 )(conventional planting density,CD) and 90 000 plants ha^(–1) (high planting density,HD),respectively.Until all the filaments protruded from the ear,at which point the plants were subjected to the removal of 1/2 (T1),1/3 (T2) and 1/4 (T3) each leaf length per plant,no leaf removal served as the control(CK).We evaluated the leaf source reduction on canopy photosynthetic matter production and N accumulation of different planting densities.Under CD,decreasing leaf source markedly decreased photosynthetic rate (P_(n)),effective quantum yield of photosystem II (ΦPSII) and the maximal efficiency of photosystem II photochemistry (F_(v)/F_(m)) at grain filling stage,reduced post-silking dry matter accumulation,harvest index (HI),and the yield.Compared with the CK,the 2-year average yields of T1,T2 and T3 treatments decreased by 35.4,23.8 and 8.3%,respectively.Meanwhile,decreasing leaf source reduced the root bleeding sap intensity,the content of soluble sugar in the bleeding sap,post-silking N uptake,and N accumulation in grain.The grain N accumulation in T1,T2 and T3 decreased by 26.7,16.5 and 12.8% compared with CK,respectively.Under HD,compared to other treatments,excising T3 markedly improved the leaf P_(n),ΦPSII and F_(v)/F_(m) at late-grain filling stage,increased the post-silking dry matter accumulation,HI and the grain yield.The yield of T3 was 9.2,35.7 and 20.1% higher than that of CK,T1 and T2 on average,respectively.The T3 treatment also increased the root bleeding sap intensity,the content of soluble sugar in the bleeding sap and post-silking N uptake and N accumulation in grain.Compared with CK,T1 and T2 treatments,the grain N accumulation in T3 increased by 13.1,40.9 and 25.2% on average,respectively.In addition,under the same source reduction treatment,the maize yield of HD was significantly higher than that of CD.Therefore,planting density should be increased in maize production for higher grain yield.Under HD,moderate decreasing leaf source improved photosynthetic performance and increased the post-silking dry matter accumulation and HI,and thus the grain yield.In addition,the improvement of photosynthetic performance improved the root function and promoted postsilking N uptake,which led to the increase of N accumulation in grain. 展开更多
关键词 different planting densities leaf source reduction canopy photosynthetic matter production post-silking N uptake grain N accumulation
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Waves induced by a submerged moving dipole in a two-layer fluidof finite depth 被引量:9
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作者 GangWei DongqiangLu ShiqiangDai 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第1期24-31,共8页
The waves induced by a moving dipole in a two-fluid system are analytically and experimentally investigated. The velocity potential of a dipole moving horizontally in the lower layer of a two-layer fluid with finite d... The waves induced by a moving dipole in a two-fluid system are analytically and experimentally investigated. The velocity potential of a dipole moving horizontally in the lower layer of a two-layer fluid with finite depth is derived by superposing Greens functions of sources (or sinks). The far-field waves are studied by using the method of stationary phase. The effects of two resulting modes, i.e. the surface- and internal-wave modes, on both the surface divergence field and the interfacial elevation are analyzed. A laboratory study on the internal waves generated by a moving sphere in a two-layer fluid is conducted in a towing tank under the same conditions as in the theoretical approach. The qualitative consistency between the present theory and the laboratory study is examined and confirmed. 展开更多
关键词 Divergence field Internal wave Small density difference Greens function The method of stationary phase
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Microsegregation and Rayleigh number variation during the solidification of superalloy Inconel 718 被引量:6
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作者 Ling Wang Jianxin Dong +1 位作者 Yuliang Tian Lei Zhang 《Journal of University of Science and Technology Beijing》 CSCD 2008年第5期594-599,共6页
The microstructure and composition of the residual liquid at different temperatures were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDX) associated with the Thermo... The microstructure and composition of the residual liquid at different temperatures were investigated by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometer (EDX) associated with the Thermo-calc software calculation of the equilibrium phase diagrams of Inconel 718 and segregated liquid. The liquid density difference and Rayleigh number variation during solidification were estimated as well. It is found that the heavy segregation of Nb in liquid prompts the precipitation of δ and Laves phase directly from liquid and the resultant quenched liquid microstructure consists of pro-eutectic γ+eutectic,or complete eutectic according to the content of Nb from low to high. The liquid density increases with decreasing temperature during the solidification of Inconel 718 and the liquid density difference is positive. The largest relative Rayleigh number occurs at 1320°C when the liquid fraction is about 40vol%. 展开更多
关键词 superalloy Inconel 718 MICROSEGREGATION liquid density difference Rayleigh number
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Excited State Properties of Fluorine-Substituted Hexabenzocoronene: A Quantum-Chemical Characterization 被引量:1
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作者 LI Yuan-Zuo SUN Yu LI Yong-Qing MA Feng-Cai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期229-232,共4页
The first fluorine-substituted hexabenzocoronene has been synthesized and its electronic structure and optical properties have been reported [Q. Zhang, et al., Org. Lett. 7 (2005) 5019]. In this letter, the electron... The first fluorine-substituted hexabenzocoronene has been synthesized and its electronic structure and optical properties have been reported [Q. Zhang, et al., Org. Lett. 7 (2005) 5019]. In this letter, the electronic structure and excited state properties of the fluorine-substituted hexabenzocoronene are studied with quantum chemistry method as well as the transition and the charge difference densities. The transition densities show the orientations and strength of the dipole moments and the charge difference densities reveal the orientation and results of the intramolecular charge transfer. The calculated transition energies and oscillator strengths are consistent with the experimental data, and the theoretical results of transition and charge difference densities are valuable to understanding the excited state properties of the fluorine-substituted hexabenzocoronene. 展开更多
关键词 intramolecular charge transfer fluorine-substituted hexabenzocoronene transition densities charge difference densities
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Study on Multi-density Contrast Agent Fillers of Duct Casting Based on CT Three-Dimensional Reconstruction 被引量:5
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作者 黄海龙 陈进军 +2 位作者 王瑜 陈小宇 龚达聪 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第2期300-306,共7页
The three-dimensional visualization model of human body duct is based on virtual anatomical structure reconstruction with duct angiography,which realizes virtual model transferred from two-dimensional,planar and stati... The three-dimensional visualization model of human body duct is based on virtual anatomical structure reconstruction with duct angiography,which realizes virtual model transferred from two-dimensional,planar and static images into three-dimensional,stereoscopic and dynamic ones repectively.In recent years,the multi-duct segmentation and division of the same specimen(or organ) is the focus of attention shared by surgeons and clinical anatomists.On the basis of 4.22 g/cm3 body bone density,this study has screened out metal oxide contract agent with different density for infusion and modeling,as well as compared and analyzed the effects of three-dimensional image of CT virtual bronchoscopy(CTVB),three-dimensional image of CT maximum intensity projection and three-dimensional model.This experiment result showed synchronously infusing multi-duct of same specimen(or organ) with contrast agent in different densities could reconstruct three-dimensional models of all ducts once only and adjust threshold to develop single or multiple ducts.It was easier to segment and observe the duct structure,anastomosis,directions and crossing in different parts,which was beyond comparison with three-dimensional image of CTVB.Although the existing three-dimensional duct reconstruction techniques still cannot be applied in living bodies temporarily,this study focused on a creative design of ducts segmentation in different density,which proposed a new experimental idea for developing multi-duct three-dimensional model in living body in the future.It will play a significant role in disease diagnosis and individual design in surgical treatment program.Therefore,this study observes the three-dimensional status of human duct with the application of contrast agent fillers in different density,combined with three-dimensional reconstruction technology.It provides an innovative idea and method for constructing three-dimensional model of digital multi-duct specimen,and the ultimate goal is to develop the digitized virtual human and precise medical treatment better and faster. 展开更多
关键词 bronchi of pig lung three-dimensional reconstruction contrast agent density difference duct casting
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Direct Visual Evidence for Neutral and Charged Hexaphyrin Aromaticity with and without Keto-Defect
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作者 Shan Zhang Peng Song +5 位作者 Sha Wang Yu-ling Chu Yuan-zuo Li Zhong Yang Yong Ding Feng-cai Ma 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第5期563-570,I0003,共9页
We use density functional theory and time-dependent together with a set of extensive mul- tidimensional visualization techniques to characterize the influence of keto effect on charge distribution at ground state and ... We use density functional theory and time-dependent together with a set of extensive mul- tidimensional visualization techniques to characterize the influence of keto effect on charge distribution at ground state and electronic transitions for neutral and charged hexaphyrin aromaticity with and without keto-defect. It is found that the aromaticity is the key fac- tor to influence the ground state Mulliken charges distribution properties, other than the meso-aryl-substituted effect. But with the enhancement of the keto-defect, the distribution changes of Mulliken charges on the hexaphyrin groups are larger than those on the pentaflu- orophenyl substituted groups, following with the aromaticity changes from nonaromatic to aromatic. Furthermore, through characterizing by transition density and charge difference density, direct visual evidence for neutral and charged aromaticity with and without keto- defect can be clearly derived, and the ability of charge transfer between units of monoradical (nonaromaticity) and singlet biradical (aromaticity) forms is much stronger than that of neutral forms. 展开更多
关键词 AROMATICITY Keto-defect PORPHYRIN Charge difference density Transitiondensity
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Characteristics of settling of dilute suspension of particles with different density at high Reynolds numbers 被引量:1
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作者 Ali Abbas Zaidi 《Particuology》 SCIE EI CAS CSCD 2021年第3期62-74,共13页
Dilute suspension of particles with same density and size develops clusters when settle at high Reynolds number(≥250).It is due to particles entrapment in the wakes produced by upstream particles.In this work,this ph... Dilute suspension of particles with same density and size develops clusters when settle at high Reynolds number(≥250).It is due to particles entrapment in the wakes produced by upstream particles.In this work,this phenomenon is studied for suspension having particles with different densities by numerical simulations.The particle-fluid interactions are modelled using immersed boundary method and inter-particle collisions are modelled using discrete element method.In simulations,settling Reynolds number is always kept above 250 and the suspension solid volume fraction is nearly 0.1 percent.Two particle density ratios(i.e.density of heavy particles to lighter particles)equal to 4:1 and 2:1 and particles with same density are studied.For each density ratio,the percentage volume fraction of each particle density is nearly varied from 0.8 to 0.2.Settling characteristics such as microstructures of settling particle,average settling velocity and velocity fluctuations of settling particles are studied.Simulations show that for different density particles settling characteristics of suspension is largely dominated by heavy particles.At the end of paper,the underlying physics is explained for the anomalies observed in simulation. 展开更多
关键词 Particle clustering at high reynolds number Suspension with different density particles Particle microstructure due to settling Immersed boundary method
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Direct visualization of the charge transfer in conjugated polymers 被引量:1
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作者 LI Yan LI YuanZuo +1 位作者 DONG Bin YANG ZhiLin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第6期1119-1123,共5页
Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated ... Ion-induced charge-transfer states in conjugated polyelectrolytes were experimentally investigated by Justin M.Hodgkiss and his co-workers [J Am Chem Soc,2009,131(25):8913].In this work,charged and neutral conjugated polyelectrolytes were further studied with quantum chemistry methods.The calculation result shows that the absorption spectra are roughly in visible and ultraviolet light regions,and the two absorption peaks are located in the wavelength span 300-400 nm for charged polyelectrolytes.However,in neutral conjugated polyelectrolytes,the peaks of the absorption spectra showed a blue shift compared with those of the charged polyelectrolytes.Charge transfer (CT) properties of the studied compounds were also investigated with both the three-dimensional real-space analysis method of transition and charge difference densities,and the two-dimensional real-space analysis method of transition density matrices based on the simulated absorption spectra.The calculation results revealed the charge transfer in conjugated polyelectrolytes on the excitation states. 展开更多
关键词 conjugated polyelectrolytes charger transfer charge difference density
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Two-phase smooth particle hydrodynamics modeling of air-water interface in aerated flows
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作者 YANG HuiXia LI Ran +2 位作者 LIN PengZhi WAN Hang FENG JingJie 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第3期479-490,共12页
Abstracted/indexed in:Science Citation Index,Science Citation Index Expanded(SciSearch),Journal Citation Reports/Science Edition,SCOPUS,INSPEC,Zentralblatt Math,Chemical Abstracts Service(CAS),Google Scholar,CSA,... Abstracted/indexed in:Science Citation Index,Science Citation Index Expanded(SciSearch),Journal Citation Reports/Science Edition,SCOPUS,INSPEC,Zentralblatt Math,Chemical Abstracts Service(CAS),Google Scholar,CSA,Academic OneFile,Current Contents/Engineering,Computing and Technology,Earthquake Engineering Abstracts,EI-Compendex,Gale,OCLC,SCImago,Summon by ProQuest Supervised by Chinese Academy of Sciences 展开更多
关键词 aerated flow dam break density difference hydraulic jump INTERFACE smoothed particle hydrodynamics
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First-Principles Prediction of Ductility in β-type Ti-Mo Binary Alloys
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作者 赖敏杰 薛祥义 +3 位作者 周中波 唐斌 李金山 周廉 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第2期227-230,共4页
Recent studies suggest that the ratio of the shear modulus (G) to the bulk modulus (B) and the Poisson's ratio (ν) are good indicators of ductility.Using the method of supercell and the first-principles pseudopot... Recent studies suggest that the ratio of the shear modulus (G) to the bulk modulus (B) and the Poisson's ratio (ν) are good indicators of ductility.Using the method of supercell and the first-principles pseudopotential plane-wave method,the G/B and ν of the β-type Ti-Mo binary alloys with Mo molar fraction (xMo) ranging from 6.25% to 37.5% are calculated.The results show that the ductility of β-type Ti-Mo binary alloys first increases with increasing x Mo and reaches the maximum when x Mo is about 25%,and then reduces with more increasing x Mo.The charge density difference calculations suggest that the x Mo dependence of the ductility can be ascribed to the change of bonding characteristics between Ti and Mo atoms in the [111] direction. 展开更多
关键词 Ti-Mo alloys FIRST-PRINCIPLES DUCTILITY charge density difference
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Vibration Characteristic Analysis and Experiment of Non-Rigid Airship with Suspended Curtain
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作者 陈宇峰 陈务军 +1 位作者 何艳丽 张大旭 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第5期625-633,共9页
In order to evaluate the vibration characteristics of non-rigid airship with suspended curtain,we introduce vibration characteristic analysis method of the inflatable membrane structure.Modal numerical method of the i... In order to evaluate the vibration characteristics of non-rigid airship with suspended curtain,we introduce vibration characteristic analysis method of the inflatable membrane structure.Modal numerical method of the inflatable membrane structure under the pressure difference is validated by the model testing of the inflatable cantilever tube.The finite element model of 75 m airships is established to simulate the vibration characteristics subjected to only pressure difference and the resultant force of weight and buoyancy.The nonlinear static deformation and stress analysis are investigated for two kinds of equilibrated configurations with various pressure differences,as well as the vibration characteristics.The structural efficiency of the suspended curtain is investigated through the force transfer ratio at the assumed equilibrated point.The effects of manufacture error of the suspended cable length on the structural behavior are analyzed.The results indicate that the local area of airship envelope connected to the suspended cable is a weak part.Various pressures and pressure gradients have significant effects on the global airship structure and the suspended curtain.The suspended curtain is effective to transfer the equilibrated force from the bottom to the top of airship envelope.Manufacture error of the suspended cable length could result in obvious deformation of local airship envelope.The presented work is valuable to the structural engineering design of stratospheric airship. 展开更多
关键词 non-rigid airship suspended curtain pressure difference net buoyant density manufacture error
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