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Structure Regulation of Electric Double Layer via Hydrogen Bonding Effect to Realize High-Stability Lithium-Metal Batteries
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作者 Sheng Liu Chaozhu Shu +8 位作者 Yu Yan Dayue Du Longfei Ren Ting Zeng Xiaojuan Wen Haoyang Xu Xinxiang Wang Guilei Tian Ying Zeng 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期72-83,共12页
The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulat... The interfacial chemistry of solid electrolyte interphases(SEI)on lithium(Li)electrode is directly determined by the structural chemistry of the electric double layer(EDL)at the interface.Herein,a strategy for regulating the structural chemistry of EDL via the introduction of intermolecular hydrogen bonds has been proposed(p-hydroxybenzoic acid(pHA)is selected as proof-of-concept).According to the molecular dynamics(MD)simulation and density functional theory(DFT)calculation results,the existence of hydrogen bonds realizes the anion structural rearrangement in the EDL,reduces the lowest unoccupied molecular orbital(LUMO)energy level of anions in the EDL,and the number of free solvent molecules,which promotes the formation of inorganic species-enriched SEI and eventually achieves the dendrite-free Li deposition.Based on this strategy,Li‖Cu cells can stably run over 185 cycles with an accumulated active Li loss of only 2.27 mAh cm^(-2),and the long-term cycle stability of Li‖Li cells is increased to 1200 h.In addition,the full cell pairing with the commercial LiFePO_(4)(LFP)cathodes exhibits stable cycling performance at 1C,with a capacity retention close to 90%after 200 cycles. 展开更多
关键词 electric double layer electrolyte additives intermolecular hydrogen bonds Li metal batteries p-Hydroxybenzoic acid
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Superposition of dual electric fields in covalent organic frameworks for efficient photocatalytic hydrogen evolution
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作者 Chao Li Shuo Wang +8 位作者 Yuan Liub Xihe Huang Yan Zhuang Shuhong Wu Ying Wang Na Wen Kaifeng Wu Zhengxin Ding Jinlin Long 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期164-175,共12页
Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen ... Covalent organic frameworks(COFs)are promising materials for converting solar energy into green hydrogen.However,limited charge separation and transport in COFs impede their application in the photocatalytic hydrogen evolution reaction(HER).In this study,the intrinsically tunable internal bond electric field(IBEF)at the imine bonds of COFs was manipulated to cooperate with the internal molecular electric field(IMEF)induced by the donor-acceptor(D-A)structure for an efficient HER.The aligned orientation of IBEF and IMEF resulted in a remarkable H_(2) evolution rate of 57.3 mmol·g^(-1)·h^(-1)on TNCA,which was approximately 520 times higher than that of TCNA(0.11 mmol·g^(-1)·h^(-1))with the opposing electric field orientation.The superposition of the dual electric fields enables the IBEF to function as an accelerating field for electron transfer,kinetically facilitat-ing the migration of photogenerated electrons from D to A.Furthermore,theoretical calculations indicate that the inhomogeneous charge distribution at the C and N atoms in TNCA not only pro-vides a strong driving force for carrier transfer but also effectively hinders the return of free elec-trons to the valence band,improving the utilization of photoelectrons.This strategy of fabricating dual electric fields in COFs offers a novel approach to designing photocatalysts for clean energy synthesis. 展开更多
关键词 Covalent organic framework Internal molecular electric field Internal bond electric field PHOTOCATALYSIS Hydrogen evolution
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Influence of operation number on arc erosion behavior of Ag/Ni electrical contact materials 被引量:3
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作者 Run-zhang HUANG Guo-fu XU +2 位作者 Qiong WU Meng YUAN Chun-ping WU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第8期2681-2695,共15页
Arc erosion behavior of Ag/Ni materials with different operation numbers was investigated by OM,3DOP and SEM.The results indicated that the arc erosion of Ag/10Ni electrical contact material fabricated by sintering−ex... Arc erosion behavior of Ag/Ni materials with different operation numbers was investigated by OM,3DOP and SEM.The results indicated that the arc erosion of Ag/10Ni electrical contact material fabricated by sintering−extrusion technology was more and more serious with the operation numbers increasing from 1000 to 40000.With the same operation numbers,the arc erosion on anode was more serious than that on cathode.Besides,the pores preferred to emerge around the arc effect spot during the first 10000 operations.And the morphology of the molten silver on cathode and anode was different due to the action of gravity and arc erosion.Furthermore,the relationships among arc energy,arc time,welding force,electric resistivity,temperature and mass change on contacts were discussed,which indicated that the mass loss on cathode was mainly caused by the fracture of molten bridge. 展开更多
关键词 Ag/Ni electrical contact material operation number arc erosion arc parameter
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Quality Evaluation of Diffusion Bonded Joints by Electrical Resistance Measuring and Microscopic Fatigue Testing
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作者 LI Yujia XUAN Fuzhen +1 位作者 LI Shuxin TU Shandong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第2期187-194,共8页
Micro-structure related behavior of diffusion bonding joints is a crucial issue in device and reactor fabrication of Micro Chemo Mechanical Systems.However,the previous studies have been focused on the macro mechanica... Micro-structure related behavior of diffusion bonding joints is a crucial issue in device and reactor fabrication of Micro Chemo Mechanical Systems.However,the previous studies have been focused on the macro mechanical performance of diffusion bonded joint,especially diffusion bonding conditions effects on tensile strength,shearing strength and fatigue strength.The research of interfacial micro-voids and microstructures evolution for failure mechanism has not been carried out for diffusion-bonded joints.An interfacial electrical resistance measuring method is proposed to evaluate the quality of bonded joints and verified by using two-dimensional finite-element simulation.The influences of micro void geometry on increments of resistance are analyzed and the relationship between bonded area fraction and resistance increment is established by theoretical analysis combined with simulated results.Metallographic inspections and micro-hardness testing are conducted near the interface of diffusion bonded joints.For the purpose of identifying the failure mechanisms of the joints,both microscopic tensile and fatigue tests are conducted on the self-developed in-situ microscopic fatigue testing system.Based on the microscopic observations,the mechanism of interfacial failure is addressed.The observation result shows that for 316LSS diffusion-bonded joints,microstructure evolution and effect of micro-voids play a key role in interfacial failure mechanism.Finally,a new life prediction model in terms of the increment of electrical resistance is developed and confirmed by the experimental results.The proposed study is initiated that constituted a primary interfacial failure mechanism on micron scale and provide the life prediction for reliability of components sealed by diffusion bonding. 展开更多
关键词 diffusion bonded joints interfacial failure electrical resistance microscopic fatigue testing
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Bonding interface between TiAl intermetallic compound and Ti under the electric field
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作者 王福明 陈少平 +2 位作者 胡利方 梁连杰 孟庆森 《China Welding》 EI CAS 2012年第1期34-38,共5页
TiAl intermetallic compound was synthesized and bonded together with Ti substrate synchronously by using fieldactivated and pressure-assisted synthesis (FAPAS) process. The effect of electric field on the microstruc... TiAl intermetallic compound was synthesized and bonded together with Ti substrate synchronously by using fieldactivated and pressure-assisted synthesis (FAPAS) process. The effect of electric field on the microstructure and growth pattern of the diffusion dissolution layer of TiA1/Ti interface was mainly studied. The microstructure of the diffusion dissolution layer was investigated by optical microscope (OM) and scanning electron microscope (SEM). The elements distribution of the diffusion dissolution layer was investigated by energy dispersive spectroscopy (EDS). The results show that a fine and homogeneous grain structure is obtained in sintered TiA1 intermetallic compound. Metallurgical bond is formed at the TiAl/Ti interface. The thickness of diffusion dissolution layer between TiAl and Ti changes with conduction time and current density. 展开更多
关键词 INTERFACE intermetallic compounds combustion synthesis electric field diffusion bonding
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MODAL PART ANALYSIS OF SLOSH OF THE LIQUID IN A CYLINDRICAL CONTAINER IN THE CASE OF SMALL BOND NUMBER 被引量:1
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作者 苟兴宇 王本利 +2 位作者 马兴瑞 黄怀德 李铁寿 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第9期979-984,共6页
Reconstruction of liquid free slosh modes by curved quiet free surface was investigated in the case of small Bond number by means of modal part analysis method in this paper. It is shown that the curved liquid quiet f... Reconstruction of liquid free slosh modes by curved quiet free surface was investigated in the case of small Bond number by means of modal part analysis method in this paper. It is shown that the curved liquid quiet free surface would couple the modes to form new eigen-modes while the orthogonality of the modes which participate the liquid slosh are given only by their Bessel modal parts and it would change their eigen-frequencies respectively while the orthogonality are given by their triangle function modal parts. By studying the laterally forced slosh of the liquid in a cylindrical container based on the new eigen-modes, a characteristic of modes-choosing was found. 展开更多
关键词 slosh bond number modal part modal part analysis
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RESISTANCE EFFECT OF ELECTRIC DOUBLE LAYER ON LIQUID FLOW IN MICROCHANNEL 被引量:1
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作者 龚磊 吴健康 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第10期1391-1398,共8页
Poisson-Boltzmann equation for EDL (electric double layer) and Navier- Stokes equation for liquid flows were numerically solved to investigate resistance effect of electric double layer on liquid flow in microchanne... Poisson-Boltzmann equation for EDL (electric double layer) and Navier- Stokes equation for liquid flows were numerically solved to investigate resistance effect of electric double layer on liquid flow in microchannel. The dimension analysis indicates that the resistance effect of electric double layer can be estimated by an electric resistance number, which is proportional to the square of the liquid dielectric constant and the solid surface zeta potential, and inverse-proportional to the liquid dynamic viscosity, electric conductivity and the square of the channel width. An "electric current density balancing" (ECDB) condition was proposed to evaluate the flow-induced streaming potential, instead of conventional "electric current balancing" (ECB) condition which may induce spurious local backflow in neighborhood of the solid wall of the microchannel. The numerical results of the flow rate loss ratio and velocity profile are also given to demonstrate the resistance effect of electric double layer in microchannel. 展开更多
关键词 MICROCHANNEL electric double layer electric resistance number
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Kinetic Analysis of Vectored Electric Propulsion System for Stratosphere Airship 被引量:1
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作者 Nie Ying Zhou Jianghua +2 位作者 Yang Yanchu Wang Sheng Wang Xuwei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期559-565,共7页
To enhance the controllability of stratosphere airship,a vectored electric propulsion system is used.By using the Lagrangian method,a kinetic model of the vectored electric propulsion system is established and validat... To enhance the controllability of stratosphere airship,a vectored electric propulsion system is used.By using the Lagrangian method,a kinetic model of the vectored electric propulsion system is established and validated through ground tests.The fake gyroscopic torque is first proposed,which the vector mechanism should overcome besides the inertial torque and the gravitational torque.The fake gyroscopic torque is caused by the difference between inertial moments about two principal inertial axes of the propeller in the rotating plane,appears only when the propeller is rotating and is proportional with the rotation speed.It is a sinusoidal pulse,with a frequency that is twice of the rotation speed.Considering the fake gyroscope torque pulse and aerodynamic efficiency,three blade propeller is recommended for the vectored propulsion system used for stratosphere airship. 展开更多
关键词 stratosphere airship vectored electric propulsion system kinetic model vector torque fake gyroscopic torque blade number
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Effects of variable viscosity and temperature modulation on linear Rayleigh-Bénard convection in Newtonian dielectric liquid
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作者 P.G.SIDDHESHWAR D.UMA S.BHAVYA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第11期1601-1614,共14页
The linear Rayleigh-Bénard electro-convective stability of the Newtonian dielectric liquid is determined theoretically subject to the temperature modulation with time.A perturbation method is used to compute the ... The linear Rayleigh-Bénard electro-convective stability of the Newtonian dielectric liquid is determined theoretically subject to the temperature modulation with time.A perturbation method is used to compute the critical Rayleigh number and the wave number.The critical Rayleigh number is calculated as a function of the frequency of modulation,the temperature-dependent variable viscosity,the electric field dependent variable viscosity,the Prandtl number,and the electric Rayleigh number.The effects of all three cases of modulations are established to delay or advance the onset of the convection process.In addition,how the effect of variable viscosity controls the onset of convection is studied. 展开更多
关键词 dielectric liquid TEMPERATURE DEPENDENT VARIABLE VISCOSITY electric field DEPENDENT VARIABLE VISCOSITY electric Rayleigh number TEMPERATURE modulation
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Development of a methodology for assessing the adequacy of electric power systems
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作者 Dmitry S.Krupenev Denis A.Boyarkin Dmitrii V.Iakubovskii 《Global Energy Interconnection》 EI CAS CSCD 2022年第5期543-550,共8页
This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which c... This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which complicates their analysis.The methodology development is aimed at solving two main problems:(1)increase the adequacy of modeling the processes that occur in the electric power system and (2)enhance the computational efficiency of the adequacy assessment methodology.This study proposes a new mathematical model to minimize the power shortage and enhance the adequacy of modeling the processes.The model considers quadratic power transmission losses and network coefficients.The computational efficiency of the adequacy assessment methodology is enhanced using efficient random-number generators to form the calculated states of electric power systems and machine learning methods to assess power shortages and other reliability characteristics in the calculated states. 展开更多
关键词 electric power systems ADEQUACY Power shortage minimization Pseudo-and quasi-random number generation Machine learning methods.
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Effect of Electric Current on Diffusion of Aluminum in Ti3AlC2 into Zirconium Alloy
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作者 卢博 YANG Xianjin +5 位作者 ZHOU Jie JING Lei SHEN Lu ZHOU Xiaobing DU Shiyu 黄庆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第3期645-649,共5页
The spark plasma sintering(SPS) method was used to study the mechanism of reaction interface between Zr and Ti3AlC2 with electric current going through it. It was found that electric current greatly reduced the bond... The spark plasma sintering(SPS) method was used to study the mechanism of reaction interface between Zr and Ti3AlC2 with electric current going through it. It was found that electric current greatly reduced the bonding temperature of Zr and Ti3AlC2. By the micro-structure analysis of the interface through SEM/EDS, it was found that Al atoms diffused from the Ti3AlC2 substrate into the Zr side and reacted with Zr to form the Zr-Al compounds at the interface, which is the strengthening mechanism of Ti3AlC2-Zr bonding. The thickness of reaction layers(Zr-Al alloy) was from 0.879 to 13.945 mm depending on different sintering condition. Current direction, heating rate, soaking time, pulse patterns all influenced the diffusion of Al atoms which affected the joining quality of Zr and Ti3AlC2. 展开更多
关键词 MAX phase diffusion bonding SPS electric current effect
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A MICROFABRICATED METAL GRATING OSCILLATOR FOR ELECTRIC FIELD DETECTION
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作者 Deng Kai Xia Shanhong +2 位作者 Gong Chao Chen Shaofeng Bai Qiang 《Journal of Electronics(China)》 2005年第5期564-568,共5页
This letter proposes a novel design of a Micro Electro Mechanical System (MEMS) device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the... This letter proposes a novel design of a Micro Electro Mechanical System (MEMS) device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the advantages in slide-film damping and large vibration amplitude, such a device makes atmospheric packaging a low-cost option for practical manufacture. In this letter, we present the operating principles and specifications, the design structure, as well as the finite element simulation. Computational analysis shows that our design obtains good results in device parameters setting, while its simplicity and low-cost features make it an attractive solution for applications. 展开更多
关键词 Miniature electric Field Sensor(MEFS) Anodic bonding Deep Reactive Ion Etching(DRIE)
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Increases in Lorentz Factor with Dielectric Thickness
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作者 J. W. McPherson 《World Journal of Condensed Matter Physics》 CAS 2016年第2期152-168,共17页
For many years, a Lorentz factor of L = 1/3 has been used to describe the local electric field in thin amorphous dielectrics. However, the exact meaning of thin has been unclear. The local electric field E<sub>l... For many years, a Lorentz factor of L = 1/3 has been used to describe the local electric field in thin amorphous dielectrics. However, the exact meaning of thin has been unclear. The local electric field E<sub>loc</sub> modeling presented in this work indicates that L = 1/3 is indeed valid for very thin solid dielectrics (t<sub>diel</sub> ≤ 20 monolayers) but significant deviations from L = 1/3 start to occur for thicker dielectrics. For example, L ≈ 2/3 for dielectric thicknesses of t<sub>diel</sub> = 50 monolayers and increases to L ≈ 1 for dielectric thicknesses t<sub>diel</sub> > 200 monolayers. The increase in L with t<sub>diel</sub> means that the local electric fields are significantly higher in thicker dielectrics and explains why the breakdown strength E<sub>bd</sub> of solid polar dielectrics generally reduces with dielectric thickness t<sub>diel</sub>. For example, E<sub>bd</sub> for SiO<sub>2</sub> reduces from approximately E<sub>bd</sub> ≈ 25 MV/cm at t<sub>diel</sub> = 2 nm to E<sub>bd</sub> ≈ 10 MV/cm at t<sub>diel</sub> = 50 nm. However, while E<sub>bd</sub> for SiO<sub>2</sub> reduces with t<sub>diel</sub>, all SiO<sub>2</sub> thicknesses are found to breakdown at approximately the same local electric field (E<sub>loc</sub>)<sub>bd</sub> ≈ 40 MV/cm. This corresponds to a coordination bond strength of 2.7 eV for the silicon-ion to transition from four-fold to three-fold coordination in the tetrahedral structure. 展开更多
关键词 Dielectrics Dielectric Breakdown Local electric Field Lorentz Factor Time-Dependent Dielectric Breakdown TDDB bond Breakage Thermochemical E-Model
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Environmental Assessment and Dielectric Performances of the Secondary Electrical Insulation in Low Voltage Motors Impregnated by Different Techniques
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作者 Manh Quan Nguyen Simon Dario +4 位作者 David Malec Dominique Mary Jean-Pascal Cambronne Damien Prunel Julie Orgelet 《Engineering(科研)》 2017年第10期860-873,共14页
A recent technique, using to potentially replace the conventional impregnating one in low voltage electric motors, has been studied in this communication. The conventional technique that uses?both primary and secondar... A recent technique, using to potentially replace the conventional impregnating one in low voltage electric motors, has been studied in this communication. The conventional technique that uses?both primary and secondary insulations;?i.e.: enamel and varnish, has been compared to this recent technique which only uses one component,?i.e.: self-bonding wires. Self-bonding wires polymerization is very quick compared to that of the conventional technique. Environmental impact and both dielectric and mechanical properties of these two techniques have been estimated and compared. The goal is to estimate if this recent technique has not only a better environmental footprint but also good technical properties. The dielectric properties that have been measured are the dielectric strength and?the lifetime under pulse?voltage while mechanical consists in measuring the bonding strength that is crucial for impregnation.?For that purpose, a Life Cycle Assessment (LCA) that can simultaneously evaluatenumerous impacts on ground, water and air,?has been performed. The results show clearly that the recent technique significantly reduces the environmental footprint. Both mechanical and dielectric properties are then compared and analyzed. 展开更多
关键词 electrical MOTOR Enameled WIRE Self-bonding WIRE IMPREGNATION Tech-nique Dielectric Performance Environmental Impact
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背压扰动平衡盘对涡旋压缩机黏性内流压力影响研究
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作者 刘兴旺 李庚泽 +2 位作者 刘晓明 刘国君 王龙 《机电工程》 CAS 北大核心 2024年第10期1844-1852,1884,共10页
在变转速工况下,电动涡旋压缩机背压腔中润滑油产生的背压力无法准确平衡轴向气体力。针对这一问题,提出了一种带有扰动片的背压扰动平衡盘,研究了背压扰动平衡盘对涡旋压缩机黏性内流压力的影响。首先,对背压扰动平衡盘作用原理进行了... 在变转速工况下,电动涡旋压缩机背压腔中润滑油产生的背压力无法准确平衡轴向气体力。针对这一问题,提出了一种带有扰动片的背压扰动平衡盘,研究了背压扰动平衡盘对涡旋压缩机黏性内流压力的影响。首先,对背压扰动平衡盘作用原理进行了分析,使用贝塞尔曲线构建了扰动片型线,对润滑油被扰动后的静压增量进行了公式推导,计算了扰动片出口安装角和扰动片数对润滑油静压的影响;然后,建立了含背压扰动平衡盘的背压腔模型,将流体域分为旋转域和静止域,采用旋转坐标系的方法进行了数值模拟,研究了背压腔内润滑油的压力场;最后,根据理论计算,模拟了润滑油在不同出口安装角和扰动片数下的润滑油静压,对润滑油静压与压缩机所需最佳背压进行了对比分析。研究结果表明:采用背压扰动平衡盘可以使润滑油静压增加21%,且静压增量随主轴转速的增加而增大,适当增大扰动片出口安装角可使润滑油静压增加0.032 MPa;对比最佳背压可知,扰动前润滑油静压与最佳背压相差26%,而合理设计扰动片后的润滑油静压与最佳背压相差仅为9%,极大改善了电动涡旋压缩机在变转速下的轴向平衡。 展开更多
关键词 电动涡旋压缩机 扰动片模型 出口安装角 扰动片数 变转速工况 轴向平衡 润滑油静压增量 最佳背压
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基于虚拟电厂区间主从博弈的车网互动优化调度 被引量:1
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作者 刘卫亮 闫倩文 +4 位作者 张启亮 刘帅 刘长良 康佳垚 王昕 《系统仿真学报》 CAS CSCD 北大核心 2024年第7期1559-1572,共14页
为更好地挖掘电动汽车调节潜力,解决车网互动各主体的利益冲突,并克服分布式电源出力与负荷不确定性的影响,提出了基于虚拟电厂区间主从博弈的车网互动双层优化调度模型,将虚拟电厂聚合商作为上层,电动汽车用户作为下层。上层模型采用... 为更好地挖掘电动汽车调节潜力,解决车网互动各主体的利益冲突,并克服分布式电源出力与负荷不确定性的影响,提出了基于虚拟电厂区间主从博弈的车网互动双层优化调度模型,将虚拟电厂聚合商作为上层,电动汽车用户作为下层。上层模型采用区间数描述源、荷的不确定性,以虚拟电厂聚合商的运营成本最低为优化目标,负责更新电价信息并传输至下层模型;下层模型以电动汽车用户满意度最大和成本最小为优化目标,负责求解用户充放电行为并返回至上层模型。采用融合区间可能度的改进粒子群算法,求解主从博弈最优调度结果。算例仿真表明:所提模型能够在削峰填谷的同时,统筹考虑聚合商与电动汽车用户的双边利益,并具有较好的鲁棒性。 展开更多
关键词 电动汽车 车网互动 虚拟电厂 优化调度 主从博弈 区间数
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电动公交车队规模与充电桩配置协同优化 被引量:1
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作者 熊杰 甘凯伦 +1 位作者 李同飞 陈艳艳 《交通运输工程与信息学报》 2024年第1期95-110,共16页
为了保障电动公交系统的车辆能源供给和线路顺畅运营,本文在多线路与多充电站场景下考虑线路行程时间的随机性,建立面向线路层面的电动公交系统车辆与充电桩配置双层优化模型。模型以车辆和充电桩投资成本与乘客候车成本之和的最小化为... 为了保障电动公交系统的车辆能源供给和线路顺畅运营,本文在多线路与多充电站场景下考虑线路行程时间的随机性,建立面向线路层面的电动公交系统车辆与充电桩配置双层优化模型。模型以车辆和充电桩投资成本与乘客候车成本之和的最小化为目标,对各线路车队规模、各充电站充电桩数量及线路与充电站间的充电匹配关系进行优化决策。在下层模型中,为反映随机行程时间下车辆充电过程对线路运营的影响,引入顾客源有限下的多服务台排队模型来刻画固定线路与充电站匹配下的排队充电过程;在上层模型中,考虑充电站与场站容量约束,对电动公交系统的线路与充电站匹配关系进行优化。在求解方面,首先基于排队模型设计算法求解特定线路与充电站匹配下的车队规模及充电桩数量,进而利用CPLEX求解器对线路与充电站匹配关系进行优化。在实验环节,设计不同规模的算例验证本文所提双层模型与算法框架的有效性,计算结果表明,本文所提的双层模型和算法框架可在满足充电站和场站容量限制的前提下尽可能缩减车队成本、充电桩成本与乘客候车成本;相比较两种人工经验方法,本文算法可将总成本分别降低5.65%和4.54%。 展开更多
关键词 城市交通 配置优化 排队模型 电动公交 车队规模 充电桩数量
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小Bond数条件下圆柱贮箱中液体晃动的模部分析 被引量:3
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作者 苟兴宇 王本利 +2 位作者 马兴瑞 黄怀德 李铁寿 《应用数学和力学》 EI CSCD 北大核心 1999年第9期913-918,共6页
运用模部分析方法考察了小 Bond 数条件下圆柱贮箱中弯曲静液面对液体晃动模态的重构作用· 研究表明,圆柱贮箱中的液体作小幅晃动时,参与晃动的各阶基本模态的正交性若仅由 Bessel 模部来给出,则弯曲静液面将使各阶... 运用模部分析方法考察了小 Bond 数条件下圆柱贮箱中弯曲静液面对液体晃动模态的重构作用· 研究表明,圆柱贮箱中的液体作小幅晃动时,参与晃动的各阶基本模态的正交性若仅由 Bessel 模部来给出,则弯曲静液面将使各阶模态加权耦合,形成新的特征模态;参与晃动的各阶基本模态的正交性若由三角函数模部来给出,则弯曲静液面将独立改变各阶模态的固有频率,各阶模态之间不耦合· 运用新的重构模态来研究圆柱贮箱中液体的横向受迫晃动,给出了其模态选择特征· 展开更多
关键词 bond 模部分析 圆柱贮箱 液体晃动
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DNA电击对草莓花粉活力的影响
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作者 陈思宇 杨秀蓉 +3 位作者 段可 倪迪安 李斌 高清华 《上海农业学报》 2024年第4期20-26,共7页
以‘申琪’草莓花粉为材料,结合不同电脉冲形态、电场强度和电击次数进行处理,然后在花粉萌发培养基上28℃黑暗孵育,于3、6、18、24h时用显微镜观察花粉萌发情况,探索草莓花粉电击适宜参数。结果表明:80μs方波脉冲在4.5—6.0kV/cm强度... 以‘申琪’草莓花粉为材料,结合不同电脉冲形态、电场强度和电击次数进行处理,然后在花粉萌发培养基上28℃黑暗孵育,于3、6、18、24h时用显微镜观察花粉萌发情况,探索草莓花粉电击适宜参数。结果表明:80μs方波脉冲在4.5—6.0kV/cm强度电击1次,可逆抑制花粉萌发,抑制程度与电场强度呈正相关;电击后3h花粉萌发率为CK1的36%—70%,24h时为CK1的60%—85%。方波4.5—5.0kV/cm强度电击2次产生部分可逆抑制,电击24h后花粉萌发率为CK1的20%—50%;5.5—6.0kV/cm方波脉冲电击2次和4.5—6.0kV/cm电击3次产生不可逆抑制,电击24h后花粉萌发率低于CK1的10%。用2.75—6.0kV/cm指数衰减波3.5ms脉冲电击后,花粉活力快速下降,电击18h后花粉萌发率在1%以下。综上,强度4.5—5.0kV/cm方波脉冲80μs电击2次为草莓花粉适宜电击参数。 展开更多
关键词 草莓花粉 DNA电击 电场强度 电击次数 花粉萌发
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铜渣尾矿团粒过程黏结剂筛选及黏结机理
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作者 刘江 罗立群 +3 位作者 刘成 叶远林 JChristophe Niyonzima 雷严明 《矿冶工程》 CAS 北大核心 2024年第5期89-95,104,共8页
为减少铜渣尾矿资源化利用过程的粉尘和烟气,以铜渣尾矿为原料,以羧甲基纤维素钠(CMC)、膨润土、水玻璃单独或复配为黏结剂制备铜渣球团,通过落下强度、抗压强度和生球爆裂温度考察黏结剂的成球效果,借助扫描电镜、红外光谱和Zeta电位... 为减少铜渣尾矿资源化利用过程的粉尘和烟气,以铜渣尾矿为原料,以羧甲基纤维素钠(CMC)、膨润土、水玻璃单独或复配为黏结剂制备铜渣球团,通过落下强度、抗压强度和生球爆裂温度考察黏结剂的成球效果,借助扫描电镜、红外光谱和Zeta电位测试分析球团内部微观形貌、吸附特征和表面电位变化。结果表明:3种黏结剂均可实现铜渣尾矿的团粒化黏结;黏结剂单独使用时,CMC配量应大于0.20%,膨润土配量应大于2.0%,水玻璃配量应大于2.5%;CMC与膨润土或水玻璃复配,CMC配量0.1%时,膨润土配量应大于2.0%,水玻璃配量应大于2.5%;CMC配量为0.15%时,膨润土配量应大于1.5%,水玻璃配量应大于2.0%。添加黏结剂后,球团内部结构更加紧凑,空间结构更加牢固;铜渣尾矿颗粒表面Zeta电位降低,亲水性提高,促进了颗粒间的吸附作用进而提高球团质量。 展开更多
关键词 铜渣尾矿 球团 黏结剂 黏结机理 爆裂温度 落下强度 抗压强度 ZETA电位
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