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Dissipative generation for steady-state entanglement of two transmons in circuit QED
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作者 何爽 刘丹 李明浩 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第8期50-55,共6页
We present a dissipative scheme to generate an entangled steady-state between two superconducting transmon qutrits separately embedded in two coupled transmission line resonators in a circuit quantum electrodynamics(Q... We present a dissipative scheme to generate an entangled steady-state between two superconducting transmon qutrits separately embedded in two coupled transmission line resonators in a circuit quantum electrodynamics(QED)setup.In our scheme,the resonant qutrit-resonator interaction and photon hopping between resonators jointly induce asymmetric energy gaps in the dressed state subspaces.The coherent driving fields induce the specific dressed state transition and the dissipative processes lead to the gradual accumulation in the population of target state,combination of both drives the system into a steady-state entanglement.Numerical simulation shows that the maximally entangled state can be produced with high fidelity and strong robustness against the cavity decay and qutrit decay,and no requirements for accurate time control.The scheme is achievable with the current experimental technologies. 展开更多
关键词 STEADY-STATE ENTANGLEMENT DISSIPATION dressed STATE
高烈度地区综合商业体内防屈曲约束支撑(BRB)施工技术 预览
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作者 黄威 赵璇 +2 位作者 童远志 吕正林 芦晓龙 《建筑技术》 2019年第10期1202-1204,共3页
昆明春之眼商业中心施工中,为解决普通支撑受压屈曲及滞回性能差的问题,采用防屈曲约束支撑(BRB),在支撑外部设置套筒,使用焊接或螺栓连接及销轴连接等方式进行拼合,使抑制支撑的受压屈曲形成防屈曲支撑,达到消能减震效果,保证了工程质量.
关键词 全钢结构 消能减震 防屈曲约束支撑
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吡虫啉在茶树菇及其菌棒上的残留消解动态
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作者 矫健 师迎春 吴迪 《农药》 CAS CSCD 北大核心 2019年第2期115-117,共3页
[目的]检测70%吡虫啉水分散粒剂在茶树菇及菌棒上、中、下3个部分的残留量及消解动态。[方法]采用超高效液相色谱-串联质谱法对茶树菇及其菌棒最终残留及消解动态进行研究。[结果]茶树菇和菌棒中分别添加0.005、0.05、0.5 mg/kg 3个水... [目的]检测70%吡虫啉水分散粒剂在茶树菇及菌棒上、中、下3个部分的残留量及消解动态。[方法]采用超高效液相色谱-串联质谱法对茶树菇及其菌棒最终残留及消解动态进行研究。[结果]茶树菇和菌棒中分别添加0.005、0.05、0.5 mg/kg 3个水平的吡虫啉,其平均回收率为92.0%~110.4%,相对标准偏差为2.9%~8.2%。吡虫啉在茶树菇上的降解符合一级反应动力学模式,在茶树菇和菌棒上段,吡虫啉半衰期分别为7.9、12.1 d。[结论]在茶树菇上手动喷雾施药70%吡虫啉水分散粒剂,按0.23、0.34 g a.i./m^2的剂量施药3、4次,施药间隔7d,最后1次施药距采收间隔10 d时,吡虫啉在茶树菇上的残留量近似于欧盟规定的吡虫啉在蘑菇农药残留限量0.05mg/kg。 展开更多
关键词 茶树菇 吡虫啉 残留 消解动态
Hydraulics and swimming behavior of schizothorax prenanti in vertical slot fishways 预览
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作者 Rui-dong An Jia Li +1 位作者 Wen-min Yi Xi Mao 《水动力学研究与进展:英文版》 SCIE EI CSCD 2019年第1期169-176,共8页
This paper presents a novel experiment for the correlation between the hydraulics and the swimming behavior of Schizothorax prenanti,a rare species of fish in southwest China,in passing a vertical slot fishway.With an... This paper presents a novel experiment for the correlation between the hydraulics and the swimming behavior of Schizothorax prenanti,a rare species of fish in southwest China,in passing a vertical slot fishway.With an acoustic Doppler velocimeter,the velocities of a physical model in the equidimension fishway in the Shaping II power station are measured.The hydraulic parameters include the hydraulic head drop,the velocity patterns and the flow rate,and the swimming behavior includes the burst-coast,the sustained swimming and the migratory path,and they are analyzed under the test conditions.The sustained swimming velocity is in the range from 0.65m/s to 1.09m/s.The estimated hydraulic head drop of each pool is calculated and is in the range from 0.08-0.11 m,which means that 2.6% slope is reasonable.For the same slope,the maximum velocity is further reduced from 1.24 m/s to 1.14 m/s by using an L shape baffle structure.The above findings are used as the basis to evaluate the hydraulic performance of the fishways,where the L shape baffle structure is expected to be effective tor creating a preterencial flow for the fish.For the main stream of the pool,an "Ω" shape flow pattern is more fish-friendly,which can effectively extend the energy dissipation distance and avoid the bursting through a high velocity zone.This paper provides a useful complementary tool for practical designs. 展开更多
关键词 Hydraulics SWIMMING behavior VERTICAL SLOT FISHWAYS burst-coast energy DISSIPATION
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Investigations of Viscous Dissipation in Stagnation Point Flow Past a Stretchable Riga Wall: Modern Analysis of Heat Transport
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作者 Aisha Anjum N.A.Mir +2 位作者 M.Farooq M.Javed S.Ahmad 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期377-383,共7页
This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out... This article scrutinizes the features of viscous dissipation in the stagnation point ?ow past through a linearly stretched Riga wall by implementing Cattaneo-Christov heat ?ux model. Viscous dissipation is carried out in Cattaneo-Christov diffusion analysis for the ?rst time in this letter. As a result of Cattaneo-Christov model, some extra terms of viscous dissipation are appeared in the energy equation. These extra terms of viscous dissipation are missing in the literature. On the utilization of suitable transformations, the equations governing the problem are reduced under the boundary layer approximation into the non-linear and dimensionless ordinary differential equations. Convergent approach is utilized to solve the dimensionless governing equations. The solution thus acquired is used to highlight the effects of emerging parameters on velocity distribution and ?uid’s temperature through the graphs. Features of the drag force(or skin friction co-e?cient) are graphically interpreted. It is noticed that the presence of modi?ed Hartman number helps to reduce the ?uid’s temperature but enhances the velocity pro?le. Further an enlargement in the value of thermal time relaxation parameter helps to decrease the temperature distribution. 展开更多
关键词 STAGNATION point Cattaneo-Christov theory Riga plate linear STRETCHING VISCOUS DISSIPATION
Parametric computational study on butterfly-shaped hysteretic dampers
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作者 Alireza FARZAMPOUR Matthew Roy EATHERTON 《结构与土木工程前沿:英文版》 EI CSCD 2019年第5期1214-1226,共13页
A parametric computational study is conducted to investigate the shear yielding, flexural yielding, and lateral torsional buckling limit states for butterfly-shaped links. After validating the accuracy of the finite e... A parametric computational study is conducted to investigate the shear yielding, flexural yielding, and lateral torsional buckling limit states for butterfly-shaped links. After validating the accuracy of the finite element modeling approach against previous experiments, 112 computational models with different geometrical properties were constructed and analyzed including consideration of initial imperfections. The resulting yielding moment, corresponding critical shear force, the accumulation of plastic strains through the length of links as well as the amount of energy dissipated are investigated. The results indicate that as the shape of the butterfly-shaped links become too straight or conversely too narrow in the middle, peak accumulated plastic strains increase. The significant effect of plate thickness on the buckling limit state is examined in this study. Results show that overstrength for these links (peak force divided by yield force) is between 1.2 and 4.5, with straight links producing larger overstrength. Additionally, proportioning the links to delay buckling, and designing the links to yield in the flexural mode are shown to improve energy dissipation. 展开更多
关键词 structural FUSE hystcretic DAMPER finite element analysis energy DISSIPATION initial IMPERFECTION butterfly-shaped links
呋虫胺及其代谢物在水稻生态系统中的残留检测与消解动态
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作者 葛会林 谢德芳 +3 位作者 郑雪虹 吕岱竹 李萍萍 陶珊珊 《农药学学报》 CAS CSCD 北大核心 2019年第2期211-218,共8页
为评价呋虫胺在水稻生态系统中的残留与消解行为,分别在海南、湖南和黑龙江省3地进行了规范残留试验。建立了超高效液相色谱-串联质谱(UPLC-MS/MS)检测呋虫胺(DNF)及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲(UF)与1-甲基-3-[(3-四氢呋喃... 为评价呋虫胺在水稻生态系统中的残留与消解行为,分别在海南、湖南和黑龙江省3地进行了规范残留试验。建立了超高效液相色谱-串联质谱(UPLC-MS/MS)检测呋虫胺(DNF)及其代谢物1-甲基-3-[(3-四氢呋喃)甲基]脲(UF)与1-甲基-3-[(3-四氢呋喃)甲基]二氢胍盐(DN)在水稻稻株、土壤、田水、糙米和稻壳中残留的分析方法。样品经含体积分数为1%的乙酸水溶液或乙腈溶液提取,QuEChERS方法净化,以甲醇-水混合溶液为流动相梯度洗脱,多反应监测(MRM)模式扫描,外标法定量。结果表明:3种分析物的进样浓度与其峰面积之间呈良好线性相关,R2>0.999。DNF、UF和DN在稻株、土壤、田水、糙米和稻壳中的平均回收率在71%~102%之间,在稻株、土壤、田水和糙米中的相对标准偏差(RSD)在1.2%~8.3%之间,在稻壳中的RSD在4.4%~20%之间。3种分析物在稻株、土壤、田水、糙米和稻壳中的最低检测浓度(LOQ)分别为0.1 mg/kg、0.02 mg/kg、0.01 mg/L、0.02 mg/kg和0.1 mg/kg。DNF、UF和DN的最小检出量分别为1、0.4和4 pg。3种分析物的消解半衰期分别为:DNF在稻株上为0.41~2.7 d,土壤中为1.6~4.2 d,田水中为0.90~2.2 d;DN在稻株上为2.9~13 d,土壤中为64~65 d,田水中为4.2 d;UF在稻株上为0.43~3.1 d。20%呋虫胺悬浮剂以有效成分120~180 g/hm2的剂量于水稻抽穗期施用2~3次,施药间隔期21 d,分别于距末次施药后14 d与21 d采收,呋虫胺在糙米中的残留最大值为0.11 mg/kg,低于中国制定的其在糙米上的最大残留限量标准1 mg/kg。 展开更多
关键词 呋虫胺 代谢物 水稻 残留 消解 超高效液相色谱-串联质谱(UPLC-MS/MS)
Numerical Simulation of MHD Peristaltic Flow with Variable Electrical Conductivity and Joule Dissipation Using Generalized Differential Quadrature Method
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作者 Muhammad Qasim Zafar Ali +1 位作者 Abderrahim Wakif Zoubair Boulahia 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第5期509-518,共10页
In this paper, the MHD peristaltic flow inside wavy walls of an asymmetric channel is investigated, where the walls of the channel are moving with peristaltic wave velocity along the channel length. During this invest... In this paper, the MHD peristaltic flow inside wavy walls of an asymmetric channel is investigated, where the walls of the channel are moving with peristaltic wave velocity along the channel length. During this investigation,the electrical conductivity both in Lorentz force and Joule heating is taken to be temperature dependent. Also, the long wavelength and low Reynolds number assumptions are utilized to reduce the governing partial differential equations into a set of coupled nonlinear ordinary differential equations. The new set of obtained equations is then numerically solved using the generalized differential quadrature method(GDQM). This is the first attempt to solve the nonlinear equations arising in the peristaltic flows using this method in combination with the Newton-Raphson technique. Moreover, in order to check the accuracy of the proposed numerical method, our results are compared with the results of built-in Mathematica command NDSolve. Taking Joule heating and viscous dissipation into account, the effects of various parameters appearing in the problem are used to discuss the fluid flow characteristics and heat transfer in the electrically conducting fluids graphically. In presence of variable electrical conductivity, velocity and temperature profiles are highly decreasing in nature when the intensity of the electrical conductivity parameter is strengthened. 展开更多
关键词 peristaltic flow MHD VARIABLE electrical CONDUCTIVITY Joule DISSIPATION GENERALIZED differential QUADRATURE method(GDQM)
Entransy dissipation analysis of interfacial convection enhancing gas–liquid mass transfer process based on field synergy principle
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作者 Dong Li Aiwu Zeng 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第8期1777-1788,共12页
An exploration of the gas CO2 absorbed into liquid ethanol accompanied with Rayleigh convection is performed by analyzing the mass entransy dissipation;this new statistical quantity is introduced to describe the irrev... An exploration of the gas CO2 absorbed into liquid ethanol accompanied with Rayleigh convection is performed by analyzing the mass entransy dissipation;this new statistical quantity is introduced to describe the irreversibility of mass transfer potential capacity. Based on the general advection–diffusion differential equation for an unsteady mass transfer process, the variation of the included angle between the velocity vector and concentration gradient fields is investigated to reveal the underlying mechanism of interfacial convection enhancing mass transfer. Results show some identical characteristics with the qualitative analyses of the synergy effects generated by the concentration and velocity fields after interfacial convection occurring for a boundary condition of fixed surface concentration. And the equivalent mass resistance for convective mass transfer process presents the similar variation with the reciprocal of instantaneous mass transfer coefficient. Accordingly, it is reasonable to be seen that mass transfer dissipation rate could be provided to assess the convection strength and explain fundamentally how Rayleigh convection improves mass transfer performance through establishing a close relationship between the mass transfer capacity and field synergy principle from the view of mass transfer theory. 展开更多
关键词 Field synergy Mass entransy dissipation Equivalent mass resistance Interfacial convection REINFORCEMENT
A two-step unconditionally stable explicit method with controllable numerical dissipations 预览
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作者 Li Jinze Yu Kaiping Li Xiangyang 《地震工程与工程振动:英文版》 SCIE EI CSCD 2019年第2期285-299,共15页
A family of unconditionally stable direct integration algorithm with controllable numerical dissipations is proposed. The numerical properties of the new algorithms are controlled by three parameters α,β and γ. By ... A family of unconditionally stable direct integration algorithm with controllable numerical dissipations is proposed. The numerical properties of the new algorithms are controlled by three parameters α,β and γ. By the consistent and stability analysis, the proposed algorithms achieve the second-order accuracy and are unconditionally stable under the condition that α≥-0.5,β≤ 0.5 and γ≥-(1+α)/2. Compared with other unconditionally stable algorithms, such as Chang’s algorithms and CR algorithm, the proposed algorithms are found to be superior in terms of the controllable numerical damping ratios. The unconditional stability and numerical damping ratios of the proposed algorithms are examined by three numerical examples. The results demonstrate that the proposed algorithms have a superior performance and can be used expediently in solving linear elastic dynamics problems. 展开更多
关键词 DIRECT INTEGRATION method unconditional STABILITY NUMERICAL DISSIPATION dynamic analysis
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Upshot of ohmically dissipated Darcy-Forchheimer slip flow of magnetohydrodynamic Sutterby fluid over radiating linearly stretched surface in view of Cash and Carp method 预览
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作者 S. BILAL M. SOHAIL +2 位作者 R. NAZ M. Y. MALIK M. ALGHAMDI 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第6期861-876,共16页
The present work concerns the momentum and heat transmission of the electro-magnetohydrodynamic (E-MHD) boundary layer Darcy-Forchheimer flow of a Sutterby fluid over a linear stretching sheet with slip. The nonlinear... The present work concerns the momentum and heat transmission of the electro-magnetohydrodynamic (E-MHD) boundary layer Darcy-Forchheimer flow of a Sutterby fluid over a linear stretching sheet with slip. The nonlinear equations for the proposed model are analyzed numerically. Suitable techniques are used to transform the coupled nonlinear partial differential equations (PDEs) conforming to the forced balance law, energy, and concentration equations into a nonlinear coupled system of ordinary differential equations (ODEs). Numerical solutions of the transformed nonlinear system are obtained using a shooting method, improved by the Cash and Carp coefficients. The influence of important physical variables on the velocity, the temperature, the heat flux coefficient, and the skin-friction coefficient is verified and analyzed through graphs and tables. From the comprehensive analysis of the present work, it is concluded that by intensifying the magnitude of the Hartmann number, the momentum distribution decays, whereas the thermal profile of fluid increases. Furthermore, it is also shown that by aug- menting the values of the momentum slip parameter, the velocity profile diminishes. It is found that the Sutterby fluid model shows shear thickening and shear thinning behaviors. The momentum profile shows that the magnitude of velocity for the shear thickening case is dominant as compared with the shear thinning case. It is also demonstrated that the Sutterby fluid model reduces to a Newtonian model by fixing the fluid parameter to zero. In view of the limiting case, it is established that the surface drag in the case of the Sutterby model shows a trifling pattern as compared with the classical case. 展开更多
关键词 Sutterby FLUID thermal and momentum slip shooting METHOD ohmic dissipation Darcy-Forchheimer law CASH and CARP METHOD
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Local Energy Dissipation/Transition in Field Effect Molecular Nanoelectronic Systems:a Quantum Mechanical Methodology
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作者 Reza Safari Hassan Sabzyan 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第4期441-454,共14页
Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~M) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are us... Electronic and vibrational intra-molecular thermoelectric-like ?gures of merit(ZT_γ~M) are introduced for single molecule nanoelectronic system, using quantum theory of atoms in molecule. These ?gures of merit are used to describe intra-molecular or local energy dissipation/transition(as in Joule-like, Peltier-like, and Thomson-like effects) in?eld effect molecular devices. The ZT_γ~M?gures of merit are computed for two proposed molecular devices. Analysis of the results shows that ZT_γ~Mdepends almost non-linearly on the electric ?eld(EF) strength. Also, the intra-molecular Joule-like heating plays a dominant role in the local energy dissipation, and intra-molecular Thomson-like heating is generally larger than the intra-molecular Peltier-like heating. Introduction of ZT_γ~Mcan be applied to extend the analysis of thermoelectric heating down to molecular and intra-molecular levels, and thus can be used to predict characteristics and performance of any candidate multi-terminal or multi-pole molecular systems prior to their application in real nanoelectronic circuits. 展开更多
关键词 intra-molecularheattransfer local energy DISSIPATION ?eldeffect MOLECULAR device nanoelectronic devices QTAIM
呋虫胺在水稻生态系统中的残留消解及膳食风险评估 预览
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作者 葛会林 谢德芳 +2 位作者 苏冰霞 吕岱竹 赵方方 《热带作物学报》 CSCD 北大核心 2019年第7期1434-1440,共7页
为评价呋虫胺在水稻生态系统中的残留消解行为和产生的膳食摄入风险,于2014年在海南、湖南和黑龙江进行了规范残留试验,建立了高效液相色谱法(HPLC)的分析方法检测呋虫胺在水稻糙米、稻壳、稻株、土壤、田水中的残留,并对我国不同人群... 为评价呋虫胺在水稻生态系统中的残留消解行为和产生的膳食摄入风险,于2014年在海南、湖南和黑龙江进行了规范残留试验,建立了高效液相色谱法(HPLC)的分析方法检测呋虫胺在水稻糙米、稻壳、稻株、土壤、田水中的残留,并对我国不同人群的膳食暴露风险进行了评估。样品经乙腈提取,NH2柱层析净化,高效液相色谱-紫外检测器(HPLC-UV)检测,外标法定量。结果表明,在0.02~0.5 mg/kg添加水平下,呋虫胺的平均回收率在75%~114%之间,相对标准偏差(RSD)在0.5%~19.0%之间;呋虫胺的最低检测浓度(LOQ),稻株与稻壳中为0.1 mg/kg,糙米中为0.05 mg/kg,土壤与田水中为0.02 mg/kg;呋虫胺最小检出量(LOD)为0.08 ng。呋虫胺的消解基本符合一级动力学方程,半衰期在稻株中约0.5 d,田水中约1 d,土壤中约5 d。距末次施药后14 d糙米中呋虫胺的残留中值为0.058 mg/kg,最大残留值为0.13 mg/kg,低于我国规定的最大残留限量1 mg/kg。风险评估表明中国人群对稻米中呋虫胺长期膳食摄入的慢性风险较低。 展开更多
关键词 呋虫胺 水稻 高效液相色谱 残留 消解 风险评估
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Spatial and seasonal variability of global ocean diapycnal transport inferred from Argo profiles 预览
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作者 HUANG Chao XU Yongsheng 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第2期498-512,共15页
The global diapycnal transport in the ocean interior is one of the significant branches to return the deep water back toward near-surface. However, the amount of the diapycnal transport and the seasonal variations are... The global diapycnal transport in the ocean interior is one of the significant branches to return the deep water back toward near-surface. However, the amount of the diapycnal transport and the seasonal variations are not determined yet. This paper estimates the dissipation rate and the associated diapycnal transports at 500 m, 750 m and 1 000 m depth throughout the global ocean from the wide-spread Argo profiles, using the finescale parameterizations and classic advection-diff usion balance. The net upwelling is ~5.2±0.81 Sv (Sverdrup) which is approximately one fifth in magnitude of the formation of the deep water. The Southern Ocean is the major region with the upward diapycnal transport, while the downwelling emerges mainly in the northern North Atlantic. The upwelling in the Southern Ocean accounts for over 50% of the amount of the global summation. The seasonal cycle is obvious at 500 m and vanishes with depth, indicating the energy source at surface. The enhancement of diapycnal transport occurs at 1000min the Southern Ocean, which is pertinent with the internal wave generation due to the interaction between the robust deep-reaching flows and the rough topography. Our estimates of the diapycnal transport in the ocean interior have implications for the closure of the oceanic energy budget and the understanding of global Meridional Overturning Circulation. 展开更多
关键词 DISSIPATION rate diapycnal TRANSPORT UPWELLING MERIDIONAL OVERTURNING circulation
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Dissipation function in turbulent plane Poiseuille and Couette flows subject to spanwise rotations 预览
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作者 Zhenhua XIA Yipeng SHI +1 位作者 Qingdong CAI Jie GAI 《应用数学和力学:英文版》 SCIE EI CSCD 2019年第2期185-192,共8页
The dissipation function in turbulent plane Poiseuille flows(PPFs)and plane Couette flows(PCFs)subject to spanwise rotations is analyzed.It is found that,in the PCFs without system rotations,the mean part is constant ... The dissipation function in turbulent plane Poiseuille flows(PPFs)and plane Couette flows(PCFs)subject to spanwise rotations is analyzed.It is found that,in the PCFs without system rotations,the mean part is constant while the fluctuation part follows a logarithmic law,resulting in a similar logarithmic skin friction law as PPFs.However,if the flow system rotates in the spanwise direction,no obvious dependence on the rotation number can be evaluated.In the PPFs with rotations,the dissipation function shows an increase with the rotation number,while in the PCFs with rotations,when the rotation number increases,the dissipation function first decreases and then increases. 展开更多
关键词 dissipation function spanwise rotation PLANE POISEUILLE flow(PPF) PLANE COUETTE flow(PCF)
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Heat dissipating upper body compression garment:Thermoregulatory,cardiovascular, and perceptual responses
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作者 Iker Leoz-Abaurrea Nicholas Tam Roberto Aguado-Jiménez 《运动与健康科学:英文版》 SCIE 2019年第5期450-456,共7页
Purpose:The aim of the present study was to determine the effects of an upper body compression garment(UBCG)on thermoregulatory responses during cycling in a controlled laboratory thermoneutral environment(~23℃).A se... Purpose:The aim of the present study was to determine the effects of an upper body compression garment(UBCG)on thermoregulatory responses during cycling in a controlled laboratory thermoneutral environment(~23℃).A secondary aim was to determine the cardiovascular and perceptual responses when wearing the garment.Methods:Sixteen untrained participants(age:21.3±5.7 years;peak oxygen consumption(V02 peak):50.88±8.00 mL/min/kg;mean±SD)performed 2 cycling trials in a thermoneutral environment(~23℃)wearing either UBCG or control(Con)garment.Testing consisted of a 5-min rest on a cycle ergometer,followed by 4 bouts of cycling for 14-min at ~50%VO2 peak,with 1-min rest between each bout.At the end of these bouts there was 10-min of passive recovery.During the entire protocol rectal temperature(Trec),skin temperature(Tskin),mean body temperature(Tbody),and heat storage(HS)were measured.Heart rate(HR),VO2,pH,hematocrit(Hct),plasma electrolytes,weight loss(Wloss),and perceptual responses were also measured.Results:There were no significant differences between garments for Tskin,HS,HR,VO2,pH,Hct,plasma electrolyte concentration,Wloss,and perceptual responses during the trial.Trec did not differ between garment conditions during rest,exercise,or recovery although a greater reduction in Trec wearing UBCG(p=0.01)was observed during recovery.Lower Tbody during recovery was found when wearing UBCG(36.82℃±0.30℃ vs.36.99℃±0.24℃).Conclusion:Wearing a UBCG did not benefit thermoregulatory,cardiovascular,and perceptual responses during exercise although it was found to lower Tbody during recovery,which suggests that it could be used as a recovery tool after exercise. 展开更多
关键词 Body temperature Compression GARMENT CYCLING HEAT DISSIPATION THERMOREGULATION
粘性流基于特征线的四阶Runge-Kutta有限元法 预览
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作者 廖绍凯 张研 陈达 《计算力学学报》 CAS CSCD 北大核心 2019年第2期226-232,共7页
对于二维不可压缩粘性流,通过沿流线方向的坐标变换,推导了无对流项的二维N-S(Navier-Stokes)方程。采用四阶 Runge-Kutta 法对N-S方程进行时间离散,并沿流线进行Taylor展开,得到显式的时间离散格式,然后利用Galerkin法对其进行空间离散... 对于二维不可压缩粘性流,通过沿流线方向的坐标变换,推导了无对流项的二维N-S(Navier-Stokes)方程。采用四阶 Runge-Kutta 法对N-S方程进行时间离散,并沿流线进行Taylor展开,得到显式的时间离散格式,然后利用Galerkin法对其进行空间离散,得到了高精度的有限元算法。利用本文算法对方腔驱动流和圆柱绕流进行了数值计算,通过对时间步长、网格尺寸和流场区域的计算分析,进一步验证了本文算法相比经典CBS法在时间步长、收敛性、耗散性和计算精度方面更具有优势。 展开更多
关键词 NAVIER-STOKES方程 四阶Runge-Kutta法 收敛性 耗散性 精度
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Experimental research on the multilayer compartmental particle damper and its application methods on long-period bridge structures
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作者 Zhenyuan LUO Weiming YAN +2 位作者 Weibing XU Qinfei ZHENG Baoshun WANG 《结构与土木工程前沿:英文版》 EI CSCD 2019年第4期751-766,共16页
Particle damping technology has attracted extensive research and engineering application interest in the field of vibration control due to its prominent advantages, including wide working frequency bands, ease of inst... Particle damping technology has attracted extensive research and engineering application interest in the field of vibration control due to its prominent advantages, including wide working frequency bands, ease of installation, longer durability and insensitivity to extreme temperatures. To introduce particle damping technology to long-period structure seismic control, a novel multilayer compartmental particle damper (MCPD) was proposed, and a 1/20 scale test model of a typical long-period self-anchored suspension bridge with a single tower was designed and fabricated. The model was subjected to a series of shaking table tests with and without the MCPD. The results showed that the seismic responses of the flexible or semi-flexible bridge towers of long-period bridges influence the seismic responses of the main beam. The MCPD can be conveniently installed on the main beam and bridge tower and can effectively reduce the longitudinal peak displacement and the root mean square acceleration of the main beam and tower. In addition, no particle accumulation was observed during the tests. A well-designed MCPD can achieve significant damping for long-period structures under seismic excitations of different intensities. These results indicate that the application of MCPDs for seismic control of single-tower self-anchored suspension bridges and other long-period structures is viable. 展开更多
关键词 energy dissipation devices MULTILAYER COMPARTMENTAL PARTICLE DAMPER SELF-ANCHORED suspension bridges SHAKING tables test long-period structure seismic control
16%多抗霉素B在西瓜和土壤中的残留及消解动态 预览
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作者 常培培 贺洪军 +3 位作者 张自坤 王磊 王静静 李腾飞 《果树学报》 CAS CSCD 北大核心 2019年第3期359-365,共7页
【目的】评价16%多抗霉素B可溶粒剂在西瓜上使用的安全性。【方法】利用超高效液相色谱-光电二极管阵列检测器(UPLC-PDA)对2 a(年)两地的西瓜和土壤中的多抗霉素B残留消解动态及最终残留进行测定和研究。【结果】多抗霉素B在西瓜和土壤... 【目的】评价16%多抗霉素B可溶粒剂在西瓜上使用的安全性。【方法】利用超高效液相色谱-光电二极管阵列检测器(UPLC-PDA)对2 a(年)两地的西瓜和土壤中的多抗霉素B残留消解动态及最终残留进行测定和研究。【结果】多抗霉素B在西瓜和土壤中的降解动态曲线均符合一级动力学方程,半衰期分别为1.9~3.4 d和1.6~2.2 d,最终残留试验结果表明,当施药量为每666.7 m285 g和127.5 g时,施药次数为3次和4次时,多抗霉素B在西瓜全瓜、瓜肉和土壤的残留量均<0.100 mg·kg^-1。【结论】16%多抗霉素B可溶粒剂属于易降解农药,在西瓜上的安全间隔期为5 d。 展开更多
关键词 西瓜 多抗霉素B 土壤 残留 消解
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噻虫胺和灭蝇胺在韭菜中的消解动态及初步膳食风险评估 预览
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作者 毛江胜 李慧冬 +4 位作者 陈子雷 张文君 郭长英 方丽萍 丁蕊艳 《山东农业科学》 2019年第3期118-123,共6页
建立了QuEChERS-液相色谱-质谱联用(LC-MS/MS)同时测定韭菜中噻虫胺和灭蝇胺残留量的分析方法,并采用该方法研究了这2种农药在韭菜中的消解动态及最终残留量。样品经乙腈提取,用N-丙基乙二胺(PSA)、C18和石墨化碳(PC)净化,正离子电离,... 建立了QuEChERS-液相色谱-质谱联用(LC-MS/MS)同时测定韭菜中噻虫胺和灭蝇胺残留量的分析方法,并采用该方法研究了这2种农药在韭菜中的消解动态及最终残留量。样品经乙腈提取,用N-丙基乙二胺(PSA)、C18和石墨化碳(PC)净化,正离子电离,多反应监测模式,LC-MS/MS测定,外标法定量。结果表明:在0.005~1.000 mg/kg添加水平下,噻虫胺在韭菜中的平均回收率为90.0%~95.9%,相对标准偏差(RSD)为1.7%~3.3%;灭蝇胺在韭菜中的平均回收率为94.7~98.7%,RSD为0.8%~3.0%。样品中噻虫胺和灭蝇胺的定量限(LOQ)分别为0.010、0.005 mg/kg。噻虫胺和灭蝇胺在韭菜中残留量均未检出。20%噻虫胺·灭蝇胺悬浮剂按有效成分1 800 g/hm2施药2次,施药间隔期为45 d,安全间隔期20 d,噻虫胺在韭菜中的残留量均<0.01 mg/kg,灭蝇胺在韭菜中的残留量均<0.005 mg/kg。 展开更多
关键词 噻虫胺 灭蝇胺 韭菜 残留 消解 膳食风险评估
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