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Correcting on-chip distortion of control pulses with silicon spin qubits
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作者 Ming Ni Rong-Long Ma +10 位作者 Zhen-Zhen Kong Ning Chu Wei-Zhu Liao Sheng-Kai Zhu Chu Wang Gang Luo Di Liu Gang Cao Gui-Lei Wang Hai-Ou Li Guo-Ping Guo 《Chinese Physics B》 2025年第1期265-271,共7页
In semiconductor quantum dot systems,pulse distortion is a significant source of coherent errors,which impedes qubit characterization and control.Here,we demonstrate two calibration methods using a two-qubit system as... In semiconductor quantum dot systems,pulse distortion is a significant source of coherent errors,which impedes qubit characterization and control.Here,we demonstrate two calibration methods using a two-qubit system as the detector to correct distortion and calibrate the transfer function of the control line.Both methods are straightforward to implement,robust against noise,and applicable to a wide range of qubit types.The two methods differ in correction accuracy and complexity.The first,coarse predistortion(CPD)method,partially mitigates distortion.The second,all predistortion(APD)method,measures the transfer function and significantly enhances exchange oscillation uniformity.Both methods use exchange oscillation homogeneity as the metric and are suitable for any qubit driven by a diabatic pulse.We believe these methods will enhance qubit characterization accuracy and operation quality in future applications. 展开更多
关键词 quantum computation quantum dot pulse distortion
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Linear magnetoresistance and structural distortion in layered SrCu_(4-x)P_(2) single crystals
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作者 聂勇 陈正 +10 位作者 韦文森 李慧杰 张勇 梅明 王园园 宋文海 宋东升 王钊胜 朱相德 宁伟 田明亮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期591-594,共4页
We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magne... We report a systematic study on layered metal SrCu_(4-x)P_(2) single crystals via transport, magnetization, thermodynamic measurements and structural characterization. We find that the crystals show large linear magnetoresistance without any sign of saturation with a magnetic field up to 30T. We also observe a phase transition with significant anomalies in resistivity and heat capacity at T_(p)~140 K. Thermal expansion measurement reveals a subtle lattice parameter variation near Tp, i.e.,?L_(c)/L_(c)~0.062%. The structural characterization confines that there is no structure transition below and above T_(p). All these results suggest that the nonmagnetic transition of SrCu_(4-x)P_(2) could be associated with structural distortion. 展开更多
关键词 linear magnetoresistance thermal expansion specific heat structural distortion
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Similarity Criterion and Scale Effect for Ship Distortion Model Under Combined Loads
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作者 ZHANG Yi-long WEI Peng-yu +3 位作者 DAI Ze-yu WANG Lian ZENG Qing-bo TANG Qin 《船舶力学》 EI CSCD 北大核心 2024年第12期1880-1890,共11页
For the ultimate strength model test evaluation of large ship structures, the distortion model with non-uniform ratio between the main size and the plate thickness size is usually adopted. It is the key to carry out s... For the ultimate strength model test evaluation of large ship structures, the distortion model with non-uniform ratio between the main size and the plate thickness size is usually adopted. It is the key to carry out scale model test to establish a distortion model similar to the real ship structure under combined load. A similarity criterion for ship distortion model under the combined action of bending moment and surface pressure was proposed, and the scale effect for the criterion was verified by a se ries of numerical analysis and model tests. The results show that the similarity criterion for ship distor tion model under combined loads has a certain scale effect. For the model tests of ship cabin struc tures, it is suggested that the scale range between the plate thickness scale and the main dimension scale should be controlled within 2:1, which can be used as a reference for distortion model design and ultimate strength test of large-scale ship structures. 展开更多
关键词 distortion model combined load similarity criteria scale effect ultimate strength test
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RESEARCH ON NONLINEAR DISTORTION IN AMPLIFIERS 被引量:2
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作者 王成华 包骅 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第2期182-187,共6页
Transistors are nonlinear devices, which can produce nonlinear distortion in amplifier while amplifying signals. For weak nonlinear distortion, the expressions of total harmonic distortion (THD), the second order in... Transistors are nonlinear devices, which can produce nonlinear distortion in amplifier while amplifying signals. For weak nonlinear distortion, the expressions of total harmonic distortion (THD), the second order intermodulation distortion(IM2 ), the third order intermodulation distortion(IM 3) and intercept point(IP 3) are deduced. With the aid of software Multisim, we simulate transistor common emitter amplifier, transistor common emitter amplifier with resistor in emitter, differential amplifier and differential amplifier with resistor between emitters. The simulational results and theoretical analyses are almost the same. 展开更多
关键词 nonlinear distortion intermodulation distortion intercept point negative feedback differential amplifier
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DISTORTION THEOREMS FOR SUBCLASSES OF STARLIKE MAPPINGS ALONG A UNIT DIRECTION IN C^n 被引量:4
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作者 卢金 刘太顺 王建飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1675-1680,共6页
In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of ... In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of starlike mappings to higher dimensions. We then give an upper bound estimate for biholomorphic subclasses of starlike mappings along a unit direction in a complex Banach space. 展开更多
关键词 subclasses of starlike mappings distortion theorem Banach space growththeorem
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Investigations on spectroscopic parameters, vibrational levels, classical turning points and inertial rotation and centrifugal distortion constants for the 1 + X^1∑g^+ state of sodium dimer 被引量:4
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作者 余本海 戴启润 +1 位作者 施德恒 刘玉芳 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2962-2967,共6页
The density functional theory (B3LYP, B3P86) and the quadratic configuration-interaction method including single and double substitutions (QCISD(T), QCISD) presented in Gaussian03 program package are employed to... The density functional theory (B3LYP, B3P86) and the quadratic configuration-interaction method including single and double substitutions (QCISD(T), QCISD) presented in Gaussian03 program package are employed to calculate the equilibrium internuclear distance Re, the dissociation energy De and the harmonic frequency We for the XIEg+ state of sodium dimer in a number of basis sets. The conclusion is gained that the best Re, De and We results can be attained at the QCISD/6-311G(3df,3pd) level of theory. The potential energy curve at this level of theory for this state is obtained over a wide internuclear separation range from 0.16 to 2.0 nm and is fitted to the analytic Murrell-Sorbie function. The spectroscopic parameters De, DO, Re, ωe, ωe Xe, αe and Be are calculated to be 0.7219 eV, 0.7135 eV, 0.31813 nm, 151.63 cm^-1, 0.7288 cm^-1, 0.000729 cm^-1 and 0.1449 cm^-1, respectively, which are in good agreement with the measurements. With the potential obtained at the QCISD/6-311G(3df,3pd) level of theory, a total of 63 vibrational states is found when J = 0 by solving the radial SchrSdinger equation of nuclear motion. The vibrational level, corresponding classical turning point and inertial rotation constant are computed for each vibrational state. The centrifugal distortion constants (Dr Hv, Lv, Mv, Nv and Ov) are reported for the first time for the first 31 vibrational states when J = 0. 展开更多
关键词 dissociation energy vibrational level turning point centrifugal distortion constant
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Genome-wide search for segregation distortion loci associated with the expression of complex traits in Populus tomentosa 被引量:4
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作者 Zhang De-qiang Zhang Zhi-yi Yang Kai 《Forestry Studies in China》 CAS 2007年第1期1-6,共6页
Segregation distortion of molecular markers has been reported in a broad range of organisms. It has been detected in an interspecific BC1 Populus pedigree established by controlled crossing between clone "LM50" (Po... Segregation distortion of molecular markers has been reported in a broad range of organisms. It has been detected in an interspecific BC1 Populus pedigree established by controlled crossing between clone "LM50" (Populus tomentosa) and its hybrid clone "TB01" (P. tomentosa × p. bolleana). The study with a total of 150 AFLP markers (approximately 18.9% of the total loci) exhibited significant deviation from the Mendelian ratio (1:1) (p〈0.01). Twenty-five percent of the markers were mapped on the parental specific genetic linkage maps of clones "LM50" and "TB01" with a pseudo-test-cross mapping strategy. Twelve linkage groups had markers with skewed segregation ratios, but the major regions were on linkage groups TLG2, TLG4 and TLG6 in the linkage map of clone "LM50". We also analyzed the association between distorted loci and expression of complex traits with Mapmaker/QTL software. A total of 16 putative QTLs affecting 12 traits were identified in the distorted regions on seven linkage groups. Therefore we could detect the distribution of skewed loci along the entire genome and identify the association between quantitative traits and segregation loci via genetic mapping in an interspecific BC1 P. tomentosa family. Furthermore, the genetic nature and possible causes of these segregation distortions for differentiation between female and male parents were also discussed. 展开更多
关键词 Populus tomentosa genetic mapping segregation distortion QTL mapping
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GROWTH AND DISTORTION THEOREMS FOR ALMOST STARLIKE MAPPINGS OF COMPLEX ORDER λ 被引量:3
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作者 Xiaofei ZHANG Jin LU Xiaofei LI 《Acta Mathematica Scientia》 SCIE CSCD 2018年第3期769-777,共9页
In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth the... In this article, the sharp growth theorem for almost starlike mappings of complex order λ is given firstly. Secondly, distortion theorem along a unit direction is also established as the application of the growth theorem. In particular, using our results can reduce to some well-known results. 展开更多
关键词 distortion theorem convex mapping Schwarz lemma at the boundary
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The effect of sintering and cooling process on geometry distortion and mechanical properties transition of PTFE/Al reactive materials 被引量:10
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作者 Hai-fu Wang Bao-qun Geng +3 位作者 Huan-guo Guo Yuan-feng Zheng Qing-bo Yu Chao Ge 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第3期720-730,共11页
In this research,the effect of the sintering and cooling process on geometry distortion and mechanical properties of PTFE/Al reactive material is investigated.Six particularly selected sintering temperatures,three dif... In this research,the effect of the sintering and cooling process on geometry distortion and mechanical properties of PTFE/Al reactive material is investigated.Six particularly selected sintering temperatures,three different cooling modes(annealing cooling,normalizing cooling and rapid cooling),three different initial cooling temperature s,as well as six different final cooling temperatures were designed to compare the effects of sintering temperature,cooling rate,initial cooling temperature and final cooling temperature on the properties of reactive materials.Geometry distortion was quantitatively analyzed by a statistic on the dimensional changes of the specimens and microscopic morphology.A mechanical response properties transition from brittle to ductile was found and analyzed.By combining the thermodynamic properties of PTFE and unsteady heat conduction theory,mechanisms of cooling induced morphology change,temperature induced distortion and strength decrease were obtained.The results showed that the cooling rate has the most significant effect on the morphology transformation,while initial cooling temperature has more significant effect on the dimensional distortion than final cooling temperature.As to the mechanical properties transition from brittle to plastic,a more prominent effect of initial cooling temperature than cooling rate and final temperature was revealed. 展开更多
关键词 Reactive material SINTERING COOLING Geometry distortion Mechanical properties
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Influence of the Jahn-Teller distortion on magnetic ordering in TbMn_(1-x)Fe_xO_3 被引量:2
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作者 靳金玲 张向群 +1 位作者 李国科 成昭华 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第10期451-455,共5页
The Jahn-Teller distortion plays an important role in determining the exchange interaction in rare-earth manganites.In this work we study the influence of the Jahn-Teller distortion on the magnetic structures of TbMn1... The Jahn-Teller distortion plays an important role in determining the exchange interaction in rare-earth manganites.In this work we study the influence of the Jahn-Teller distortion on the magnetic structures of TbMn1-xFexO3(x = 0,0.02,0.05,0.10,and 0.20) single crystals in the basal MnO2 plane.The decrease in the quadruple splitting with the increasing Fe doping indicates the reduction of the Jahn-Teller distortion,which makes the nearest neighboring(NN) FM interaction dominant over the next nearest neighbor(NNN) AFM interaction.This alteration is favorable for the development of A-type AFM ordering instead of the spiral magnetic ordering,which collapses when x ≥ 0.05.The analysis of dielectric data indicates that the ferroelectricity is arising from the peculiar spiral magnetic ordering. 展开更多
关键词 quadruple splitting Jahn-Teller distortion spiral magnetic ordering
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Lattice distortion in disordered antiferromagnetic XY models 被引量:1
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作者 李鹏飞 曹海静 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期495-497,共3页
The behavior of lattice distortion in spin 1/2 antiferromagnetic XY models with random magnetic modulation is investigated with the consideration of spin-phonon coupling in the adiabatic limit. It is found that lattic... The behavior of lattice distortion in spin 1/2 antiferromagnetic XY models with random magnetic modulation is investigated with the consideration of spin-phonon coupling in the adiabatic limit. It is found that lattice distortion relies on the strength of the random modulation. For strong or weak enough spin phonon couplings, the average lattice distortion may decrease or increase as the random modulation is strengthened. This may be the result of competition between the random magnetic modulation and the spin phonon coupling. 展开更多
关键词 lattice distortion random modulation spin-phonon coupling
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A new method for measuring the pulse-front distortion of arbitrary shapes in high-power ultrashort laser systems 被引量:1
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作者 左言磊 蒋东镔 +4 位作者 朱启华 董军 曾小明 黄小军 黄征 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期244-247,共4页
We present a new method that can be used to calculate pulse-front distortion by measuring the spectral interference of two point-diffraction fields in their overlapped district. We demonstrate, for the first time, the... We present a new method that can be used to calculate pulse-front distortion by measuring the spectral interference of two point-diffraction fields in their overlapped district. We demonstrate, for the first time, the measurement of the pulse-front distortion of the pulse from a complex multi-pass amplification system, which exists in almost all high-power laser systems, and obtain the irregular pulse-front distribution. The method presented does not need any reference light or assumption about the pulse-front distribution, and has an accuracy of several femtoseconds. 展开更多
关键词 pulse-front distortion multi-pass amplification high-power laser system
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The Distortion Theorems for k-fold Symmetric Quasi-convex Mappings along a Unit Direction in C^n 被引量:1
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作者 卢金 刘太顺 王建飞 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期475-479,共5页
We obtain a distortion theorem of Jacobian matrix Jf(z) for k-fold symmetric quasi-convex f along a unit direction in C^n on the unit polydisc.
关键词 quasi-convex mappings k-fold symmetric distortion theorem
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SHARP DISTORTION THEOREMS FOR A CLASS OF BIHOLOMORPHIC MAPPINGS IN SEVERAL COMPLEX VARIABLES 被引量:1
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作者 Xiaosong LIU 《Acta Mathematica Scientia》 SCIE CSCD 2022年第2期454-466,共13页
In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n... In this paper,we first establish the sharp growth theorem and the distortion theorem of the Frechet derivative for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some restricted conditions.We next give the distortion theorem of the Jacobi determinant for biholomorphic mappings defined on the unit ball of C^(n) with an arbitrary norm and the unit polydisk in C^(n) under certain restricted assumptions.Finally we obtain the sharp Goluzin type distortion theorem for biholomorphic mappings defined on the unit ball of complex Banach spaces and the unit polydisk in C^(n) with some additional conditions.The results derived all reduce to the corresponding classical results in one complex variable,and include some known results from the prior literature. 展开更多
关键词 Biholomorphic mapping distortion theorem Frechet derivative Jacobi determinant Goluzin type distortion theorem
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Mitigating the Jahn-Teller distortion driven by the spin-orbit coupling of lithium manganate cathode 被引量:2
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作者 Shu Zhang Hongyi Chen +8 位作者 Jun Chen Shouyi Yin Yu Mei Lianshan Ni Andi Di Wentao Deng Guoqiang Zou Hongshuai Hou Xiaobo Ji 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第9期379-387,I0011,共10页
Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources.However,the wholesale application of LiMn_(2)O_(4)is pr... Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources.However,the wholesale application of LiMn_(2)O_(4)is predominately plagued by its severe capacity degradation,mainly associated with the innate Jahn-Teller effect.Herein,single-crystalline LiMn_(2)O_(4)with Eu^(3+) doping is rationally designed to mitigate the detrimental Jahn-Teller distortion by tuning the chemical environment of MnO_(6) octahedra and accommodating localized electron,based on the unique aspheric flexible 4f electron orbit of rare-earth metal ions.Notably,the stretching of MnO_(6) octahedron stemmed from the Jahn-Teller effect in Eu-doped LiMn_(2)O_(4)is effectively suppressed,confirmed by theoretical calculation.Meanwhile,the structural stability of the material has been significantly enhanced due to the robust Mn–O band coherency and weakened phase transition,proved by synchrotron radiation absorption spectrum and operando X-ray diffraction.The corresponding active cathode manifests superior long-cycle stability after 300 loops at 2C and displays only a 0.011%capacity drop per cycle even at 5C.Given this,this modification tactic sheds new light on achieving superior long-cycle performances by suppressing distortion in various cathode materials. 展开更多
关键词 Spinel lithium manganate Spin-orbit coupling Jahn-Teller distortion Cathode material
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High Order Centrifugal Distortion Corrections to Energy Levels of Asymmetric Top Molecules 被引量:1
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作者 LIU Yu-Yan LIU Xiao-Yong +4 位作者 LIU Hong-Ping GUO Yuan-Qing HUANG Guang-Ming LIN Jie-Li GAO Hui 《Chinese Physics Letters》 SCIE CAS CSCD 2000年第12期879-881,共3页
High order centrifugal distortion terms have been derived and added to the effective Hamiltonian of asymmetric top molecules.Based on this Hamiltonian,a program in Fortran 77 has been developed for spectral analysis o... High order centrifugal distortion terms have been derived and added to the effective Hamiltonian of asymmetric top molecules.Based on this Hamiltonian,a program in Fortran 77 has been developed for spectral analysis of asymmetric top molecules.The high order centrifugal distortion terms are found to be non-negligible even for the low-lying rotational transitions of molecules,such as H218O,subjected to severe centrifugal distortion effect,and for the high-lying rotational transitions of molecules,such as 14N16O2 subjected to the moderate centrifugal distortion effect. 展开更多
关键词 distortion HAMILTONIAN TRANSITIONS
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Structure distortion, optical and electrical properties of ZnO thin films co-doped with Al and Sb by sol-gel spin coating 被引量:1
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作者 钟文武 刘发民 +3 位作者 蔡鲁刚 周传仓 丁芃 张嬛 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期515-519,共5页
ZnO thin films co-doped with A1 and Sb with different concentrations and a fixed molar ratio of AlCl3 to SbCl3 at 1:2, are prepared by a sol-gel spin-coating method on glass annealed at 550 ℃ for 2 h in air. The x-r... ZnO thin films co-doped with A1 and Sb with different concentrations and a fixed molar ratio of AlCl3 to SbCl3 at 1:2, are prepared by a sol-gel spin-coating method on glass annealed at 550 ℃ for 2 h in air. The x-ray diffraction results confirm that the ZnO thin films co-doped with Al distortion, and the biaxial stresses are 1.03× 10^8. 3.26× 10^8 and Sb are of wurtzite hexagonal ZnO with a very small 5.23 × 10^8, and 6.97× 10^8 Pa, corresponding to those of the ZnO thin films co-doped with Al and Sb in concentrations of 1.5, 3.0, 4.5, 6.0 at% respectively. The optical properties reveal that the ZnO thin films co-doped with Al and Sb have obviously enhanced transmittance in the visible region. The electrical properties show that ZnO thin film co-doped with Al and Sb in a concentration of 1.5 at% has a lowest resistivity of 2.5 Ω·cm. 展开更多
关键词 ZnO thin films co-doped with Al and Sb sol-gel spin-coating method structure distortion optical and electrical properties
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Influence of Tacking Sequence on Residual Stress and Distortion of Single Sided Fillet Submerged Arc Welded Joint 被引量:2
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作者 Arpan Kumar Mondal Pankaj Biswas Swarup Bag 《Journal of Marine Science and Application》 CSCD 2015年第3期250-260,共11页
Submerged arc welding (SAW) is advantageous for joining high thickness materials in large structure due to high material deposition rate. The non-uniform heating and cooling generates the thermal stresses and subseq... Submerged arc welding (SAW) is advantageous for joining high thickness materials in large structure due to high material deposition rate. The non-uniform heating and cooling generates the thermal stresses and subsequently the residual stresses and distortion. The longitudinal and transverse residual stresses and angular distortion are generally measured in large panel structure of submerged arc welded fillet joints. Hence, the objective of this present work is to quantify the amount of residual stress and distortion in and around the weld joint due to positioning of stiffeners tack. The tacking sequence influences the level of residual stress and proper controlling of tacking sequences is required to minimize the stress. In present study, an elasto-plastic material behavior is considered to develop the thermo mechanical model which predicts the residual stress and angular distortion with varying tacking sequences. The simulated result reveals that the tacking sequence heavily influences the residual stress and deformation pattern of the single sided fillet joint. The finite element based numerical model is calibrated by comparing the experimental data from published literature. Henceforth, the angular distortions are measured from an in-house developed experimental set-up. A fair agreement between the predicted and experimental results indicates the robustness of the developed numerical model. However, the most significant conclusion from present study states that tack weld position should be placed opposite to the fillet weld side to minimize the residual stress. 展开更多
关键词 residual stress distortion submerged arc welding (SAW) material deposition finite element method
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On the Estimates of Hyperbolic Area Distortion of Quasiconformal Mappings 被引量:1
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作者 CHEN Xing-di HUANG Xin-zhong 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期137-142,共6页
The distortion property of hyperbolic area of planar quasiconformal mappings is studied in this paper. In the case of radial quasiconformal mappings and angular deformed quasiconformal mappings their hyperbolic area d... The distortion property of hyperbolic area of planar quasiconformal mappings is studied in this paper. In the case of radial quasiconformal mappings and angular deformed quasiconformal mappings their hyperbolic area distortions are estimated quite sharply. The result can be applied to judge whether the hyperbolic area of a planar subset is explodable. 展开更多
关键词 hyperbolic area quasiconformal mapping explodable set distortion estimate
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Enhanced stability and rate performance of zinc-doped cobalt hexacyanoferrate (CoZnHCF) by the limited crystal growth and reduced distortion 被引量:1
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作者 Jihwan Kim Seong-Hoon Yi +1 位作者 Li Li Sang-Eun Chun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第6期649-658,I0018,共11页
Cobalt hexacyanoferrate (CoHCF) is a potential cathode for aqueous Na-ion batteries due to its high theoretical specific capacity (170 m Ah g^(-1));however,its lower rate capability and cyclability limit its applicati... Cobalt hexacyanoferrate (CoHCF) is a potential cathode for aqueous Na-ion batteries due to its high theoretical specific capacity (170 m Ah g^(-1));however,its lower rate capability and cyclability limit its applications.Structural distortion at a weak N-coordinated crystal field during cycling disintegrates Co,yielding an irreversible reaction.Different Zn amounts ranging 0–1 were added to the Co site to suppress the structural irreversibility of CoHCF,yielding Co_(1-x)Zn_(x)HCF powder;this Zn (x≤0.09) addition reduced the powder’s dimension because the lower four coordination of Zn–N,not the six coordination of Co–N,limits the powder growth.Simultaneously,a small lattice parameter and interaxial angle (~90°) are obtained,implying that a narrower Co_(1-x)Zn_(x)HCF inner structure is formed to accommodate Na ions.Moreover,the electronic conductivity of Co_(1-x)Zn_(x)HCF gradually increased within 0–0.09 range.A smaller particle size with a high surface area leads to a near-surface-limited redox process,similar to a capacitive reaction.Both the surface-limited reaction and electronic conductivity enhances the reversibility due to the smaller charge transfer resistance at the electrode/electrolyte interface caused by Zn addition.Replacing redox-active Co with non-active Zn amount of 0.07 (Co_(1-x)Zn_(x)HCF) slightly reduces the specific capacity from 127 to 119 mAh g^(-1)at 0.1 A g^(-1)due to the shrunken Co charging sites.Rate performance is enhanced by compromising the capacity and reduced distortion,resulting in 81%retention at a 20-times-faster charging rate.Notably,the Co_(1-x)Zn_(x)HCF sample exhibited the good stability while preserving 74%of the initial capacity at 0.5 A g^(-1)after 200 cycles. 展开更多
关键词 Cobalt hexacyanoferrate Rate capability STABILITY Growth limitation Structural distortion Near-surface-limited redox process
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