资源类型

期刊论文 143

会议视频 6

年份

2023 15

2022 18

2021 14

2020 11

2019 11

2018 6

2017 6

2016 6

2015 8

2014 1

2013 3

2012 4

2011 5

2010 3

2009 4

2008 6

2007 7

2006 4

2005 1

2004 1

展开 ︾

关键词

电动汽车 9

2022全球十大工程成就 4

发展 2

固体氧化物燃料电池 2

电力系统 2

电动汽车充电 2

电导率 2

超导应用 2

10kV高压电力电缆 1

12相整流 1

Halbach阵列 1

[BMIm]PF6 1

[C6MIm]PF6 1

[PMIm]PF6 1

一体化停车棚 1

中长期 1

二线隧道 1

互联网 1

交直流同时供电 1

展开 ︾

检索范围：

排序： 展示方式：

Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

《结构与土木工程前沿（英文）》 2018年 第12卷 第1期   页码 125-136 doi: 10.1007/s11709-017-0396-8

摘要： In this paper, we propose a 3D stochastic model to predict the percolation threshold and the effective electric conductivity of CNTs/Polymer composites. We consider the tunneling effect in our model so that the unrealistic interpenetration can be avoided in the identification of the conductive paths between the CNTs inside the polymer. The results are shown to be in good agreement with reported experimental data.

关键词： electrical percolation     CNTs/Polymer composites     fracture model     electric conductivity     tunnelling effects    

HTML PDF 收藏

Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2088-2100 doi: 10.1007/s11705-023-2352-6

摘要： Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor application

关键词： nickel ferrite conductivity     carbon oxygen vacancies    

HTML PDF 收藏

Permeability and thermal conductivity of host compressed natural graphite for consolidated activated

Bo TIAN, Liwei WANG, Zhequan JIN, Ruzhu WANG

《能源前沿（英文）》 2011年 第5卷 第2期   页码 159-165 doi: 10.1007/s11708-011-0145-y

摘要： Permeability and thermal conductivity test units were set up to study the heat and mass transfer performance of the host material, i.e. expanded natural graphite (ENG), for consolidated activated carbon (AC) adsorbent. The permeability was tested with nitrogen as the gas source, and the thermal conductivity was studied using steady-state heat source method. The results showed that the values of permeability and thermal conductivity were 10 to 10 m and 1.7 to 3.2 W/(m·K), respectively, while the density compressed expanded natural graphite (CENG) varied from 100 to 500 kg/m . The permeability decreased with the increasing density of CENG, whereas the thermal conductivity increased with the increasing density of CENG. Then the thermal conductivity and permeability of granular AC were researched. It was discovered that the thermal conductivity of samples with different grain size almost kept constant at 0.36 W/(m·K) while the density was approximately 600 kg/m . This means that the thermal conductivity was not related to the grain size of AC. The thermal conductivity of CENG was improved by 5 to 10 times compared with that of granular AC. Such a result showed that CENG was a promising host material for AC to improve the heat transfer performance, while the mass transfer performance should be considered in different conditions for utilization of adsorbent.

关键词： permeability     thermal conductivity     expanded nature graphite     activated carbon    

HTML PDF 收藏

Equivalent thermal conductivity of heat pipes

LU Zesheng, MA Binghui

《机械工程前沿（英文）》 2008年 第3卷 第4期   页码 462-466 doi: 10.1007/s11465-008-0087-1

摘要： In precision machining, the machining error from thermal distortion carries a high proportion of the total errors. If a precision machining tool can transfer heat fast, the thermal distortion will be reduced and the machining precision will be improved. A heat pipe working based on phase transitions of the inner working liquid transfers heat with high efficiency and is widely applied in spaceflight and chemical industries. In mechanics, applications of heat pipes are correspondingly less. When a heat pipe is applied to a hydrostatic motorized spindle, the thermal distortion cannot be solved during the heat transfer process because thermal conductivity or equivalent thermal conductivity should be provided first for special application in mechanics. An equivalent thermal conductivity model based on equivalent thermal resistances is established. Performance tests for a screen wick pipe, gravity pipe, and rotation heat pipe are done to validate the efficiency of the equivalent thermal conductivity model. The proposed model provides a calculation method for the thermal distortion analysis of heat pipes applied in the motorized spindle.

关键词： proposed     distortion analysis     hydrostatic motorized     motorized spindle     Performance    

HTML PDF 收藏

Tailoring electrical conductivity of two dimensional nanomaterials using plasma for edge electronics:

Aswathy Vasudevan, Vasyl Shvalya, Aleksander Zidanšek, Uroš Cvelbar

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 427-443 doi: 10.1007/s11705-019-1805-4

摘要： Since graphene has been discovered, two-dimensional nanomaterials have attracted attention due to their promising tunable electronic properties. The possibility of tailoring electrical conductivity at the atomic level allows creating new prospective 2D structures for energy harvesting and sensing-related applications. In this respect, one of the most successful way to manipulate the physical properties of the aforementioned materials is related to the surface modification techniques employing plasma. Moreover, plasma-gaseous chemical treatment can provide a controlled change in the bandgap, increase sensitivity and significantly improve the structural stability of material to the environment as well. This review deals with recent advances in the modification of 2D carbon nanostructures for novel ‘edge’ electronics using plasma technology and processes.

关键词： graphene     edge electronics     2D nanomaterials     plasma     electrical conductivity    

HTML PDF 收藏

Modeling of ion conductivity in Nafion membranes

YANG Zhen, PENG Xiaofeng, WANG Buxuan, DUAN Yuanyuan, LEE Duujong

《能源前沿（英文）》 2007年 第1卷 第1期   页码 58-66 doi: 10.1007/s11708-007-0005-y

摘要： A theoretical investigation was conducted to describe the ion transport behavior in a Nafion Membrane of proton exchange membrane fuel cells (PEMFC). By analyzing the surface energy configuration of the ionic clusters in a Nafion membrane, an equivalent field intensity, , was introduced to facilitate the analysis of surface resistance against ion conduction in the central region of clusters. An expression was derived for ionic conductivity incorporating the influence of surface resistance. A face-centered cubic (FCC) lattice model for a spatial cluster distribution was used to modify the effect of water content on ionic conductivity in the polymeric matrix, i.e., the regions between clusters. Compared with the available empirical correlations, the new expression showed much better agreement with the available experimental results, which indicates the rationality to consider the structural influence on ion conduction in water-swollen Nafion membranes.

关键词： face-centered     polymeric     theoretical investigation     conduction     equivalent    

HTML PDF 收藏

Techno-economic analysis of the adoption of electric vehicles

Donald KENNEDY, Simon P. PHILBIN

《工程管理前沿（英文）》 2019年 第6卷 第4期   页码 538-550 doi: 10.1007/s42524-019-0048-x

摘要： Significant advances in battery technology are creating a viable marketspace for battery powered passenger vehicles. Climate change and concerns over reliable supplies of hydrocarbons are aiding in the focus on electric vehicles. Consumers can be influenced by marketing and emotion resulting in behaviors that may not be in line with their stated objectives. Although sales of electric vehicles are accelerating, it may not be clear that purchasing an electric vehicle is advantageous from an economic or environmental perspective. A techno- economic analysis of electric vehicles comparing them against hybrids, gasoline and diesel vehicles is presented. The results show that the complexity of electrical power supply, infrastructure requirements and full life cycle concerns show that electric vehicles have a place in the future but that ongoing improvements will be required for them to be clearly the best choice for a given situation.

关键词： BEV     battery powered electric vehicle     environmental impact of electric vehicles     techno-economic analysis     gasoline versus electric powered cars     diesel versus electric cars     consumer behaviour    

HTML PDF 收藏

phosphorus-nitrogen based flame retardant and multi-walled carbon nanotubes for enhanced electrical conductivity

Yong Luo, Yuhui Xie, Renjie Chen, Ruizhi Zheng, Hua Wu, Xinxin Sheng, Delong Xie, Yi Mei

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1332-1345 doi: 10.1007/s11705-021-2035-0

摘要： Design and exploitation of flame retardant polymers with high electrical conductivity are desired for polymer applications in electronics. Herein, a novel phosphorus-nitrogen intumescent flame retardant was synthesized from pentaerythritol octahydrogen tetraphosphate, phenylphosphonyl dichloride, and aniline. Low-density polyethylene was combined with the flame retardant and multi-walled carbon nanotubes to form a nanocomposite material via a ball-milling and hot-pressing method. The electrical conductivity, mechanical properties, thermal performance, and flame retardancy of the composites were investigated using a four-point probe instrument, universal tensile machine, thermogravimetric analysis, and cone calorimeter tests, respectively. It was found that the addition of multi-walled carbon nanotubes can significantly improve the electrical conductivity and mechanical properties of the low-density polyethylene composites. Furthermore, the combination of multi-walled carbon nanotubes and phosphorus–nitrogen flame retardant remarkably enhances the flame retardancy of matrixes with an observed decrease of the peak heat release rate and total heat release of 49.8% and 51.9%, respectively. This study provides a new and effective methodology to substantially enhance the electrical conductivity and flame retardancy of polymers with an attractive prospect for polymer applications in electrical equipment.

关键词： MWCNTs     PEPA     electrical conductivity     flame retardant     low density polyethylene    

HTML PDF 收藏

Stem cell niches and endogenous electric fields in tissue repair

null

《医学前沿（英文）》 2011年 第5卷 第1期   页码 40-44 doi: 10.1007/s11684-011-0108-z

摘要：

Adult stem cells are responsible for homeostasis and repair of many tissues. Endogenous adult stem cells reside in certain regions of organs, known as the stem cell niche, which is recognized to have an important role in regulating tissue maintenance and repair. In wound healing and tissue repair, stem cells are mobilized and recruited to the site of wound, and participate in the repair process. Many regulatory factors are involved in the stem cell-based repair process, including stem cell niches and endogenous wound electric fields, which are present at wound tissues and proved to be important in guiding wound healing. Here we briefly review the role of stem cell niches and endogenous electric fields in tissue repair, and hypothesize that endogenous electric fields become part of stem cell niche in the wound site.

关键词： stem cell     stem cell niche     electric field     tissue repair    

HTML PDF 收藏

Characterization of 3D microstructure, thermal conductivity, and heat flow of cement-based foam using

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 643-651 doi: 10.1007/s11709-021-0709-9

摘要： This study presents the results of the 3D microstructure, thermal conductivity, and heat flow in cement-based foams and examines their changes with a range of densities. Images were captured using X-ray micro computed tomography (micro-CT) imaging technique on cement-based foam samples prepared with densities of 400, 600, and 800 kg/m3. These images were later simulated and quantified using 3D data visualization and analysis software. Based on the analysis, the pore volume of 11000 µm3 was determined across the three densities, leading to optimal results. However, distinct pore diameters of 15 µm for 800 kg/m3, and 20 µm for 600 and 400 kg/m3 were found to be optimum. Most of the pores were spherical, with only 10% appearing elongated or fractured. In addition, a difference of 15% was observed between the 2D and 3D porosity results. Moreover, a difference of 5% was noticed between the experimentally measured thermal conductivity and the numerically predicted value and this variation was constant across the three cast densities. The 3D model showed that heat flows through the cement paste solids and with an increase in porosity this flow reduces.

关键词： 3D pore volume distribution     X-ray tomography     3D shape factor     heat flow    

HTML PDF 收藏

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced conductivity

《化学科学与工程前沿（英文）》 2023年 第17卷 第2期   页码 206-216 doi: 10.1007/s11705-022-2203-x

摘要： Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important organic electrode for solution-processed low-cost electronic devices. However, it requires doping and post-solvent treatment to improve its conductivity, and the chemicals used for such treatments may affect the device fabrication process. In this study, we developed a novel route for exploiting ultrafast lasers (femtosecond and picosecond laser) to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices. The conductivity of the PEDOT:PSS film was improved by three orders of magnitude (from 3.1 to 1024 S·cm–1), and high transparency of up to 88.5% (average visible transmittance, AVT) was achieved. Raman and depth-profiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced, thereby increasing the carrier concentration. The surface PSS content also decreased, which is beneficial to the carrier mobility, resulting in significantly enhanced electrical conductivity. Further, we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes, and a power conversion efficiency of 7.39% was achieved with 22.63% AVT. Thus, the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics.

关键词： PEDOT:PSS     ultrafast laser     transparent electrode     ST-PSCs     patterning    

HTML PDF 收藏

Recent progress in electric-field assisted combustion: a brief review

《能源前沿（英文）》 2022年 第16卷 第6期   页码 883-899 doi: 10.1007/s11708-021-0770-z

摘要： The control of combustion is a hot and classical topic. Among the combustion technologies, electric-field assisted combustion is an advanced techno-logy that enjoys major advantages such as fast response and low power consumption compared with thermal power. However, its fundamental principle and impacts on the flames are complicated due to the coupling between physics, chemistry, and electromagnetics. In the last two decades, tremendous efforts have been made to understand electric-field assisted combustion. New observations have been reported based on different combustion systems and improved diagnostics. The main impacts, including flame stabilization, emission reduction, and flame propagation, have been revealed by both simulative and experimental studies. These findings significantly facilitate the application of electric-field assisted combustion. This brief review is intended to provide a comprehensive overview of the recent progress of this combustion technology and further point out research opportunities worth investigation.

关键词： electric field     combustion     flame stabilization     emission reduction     flame propagation    

HTML PDF 收藏

Design and characteristics of electric supercharger for diesel engine acceleration by additional rapid

YAO Chun-de, ZHOU Hong-xiu

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 409-412 doi: 10.1007/s11465-006-0048-5

摘要： The ES (electric supercharger) driven by a high-speed brushless motor was developed to solve the problem of smoke caused by the turbocharger s sluggish response during acceleration. Its rotation speed was from 6 000 r/min to 24 000 r/min, and the maximum flux was 0.1 kg/s. The structural design of the electric supercharger is novel, which makes it easier to set the lubricating installation and to assemble. The velocity distribution at the outlet of the electric supercharger is determined by hot-wire anemometry under various rotation speeds in steady state. Furthermore, the trends of the flux and charge rate with various speeds were analyzed. In addition, the transient response was detected from the motor setup to smooth running within 10 s, 15 s, 20 s and 25 s respectively, and the characteristic of the transient flux is under pilot study. Research results indicate that the electric supercharger can respond rapidly with the great flux, and it is independent of the operating conditions of a diesel engine. Therefore, it is a feasible way to reduce smoke emission and improve the acceleration performance.

关键词： acceleration     velocity distribution     high-speed brushless     turbocharger     electric supercharger    

HTML PDF 收藏

Lightweight design of an electric bus body structure with analytical target cascading

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0718-y

摘要： Lightweight designs of new-energy vehicles can reduce energy consumption, thereby improving driving mileage. In this study, a lightweight design of a newly developed multi-material electric bus body structure is examined in combination with analytical target cascading (ATC). By proposing an ATC-based two-level optimization strategy, the original lightweight design problem is decomposed into the system level and three subsystem levels. The system-level optimization model is related to mass minimization with all the structural modal frequency constraints, while each subsystem-level optimization model is related to the sub-structural performance objective with sub-structure mass constraints. To enhance the interaction between two-level systems, each subsystem-level objective is reformulated as a penalty-based function coordinated with the system-level objective. To guarantee the accuracy of the model-based analysis, a finite element model is validated through experimental modal test. A sequential quadratic programming algorithm is used to address the defined optimization problem for effective convergence. Compared with the initial design, the total mass is reduced by 49 kg, and the torsional stiffness is increased by 17.5%. In addition, the obtained design is also validated through strength analysis.

关键词： electric vehicle     body in white (BIW)     lightweight     analytical target cascading (ATC)    

HTML PDF 收藏

Largely reduced cross-plane thermal conductivity of nanoporous In

Dongchao XU, Quan WANG, Xuewang WU, Jie ZHU, Hongbo ZHAO, Bo XIAO, Xiaojia WANG, Xiaoliang WANG, Qing HAO

《能源前沿（英文）》 2018年 第12卷 第1期   页码 127-136 doi: 10.1007/s11708-018-0519-5

摘要： In recent year, nanoporous Si thin films have been widely studied for their potential applications in thermoelectrics, in which high thermoelectric performance can be obtained by combining both the dramatically reduced lattice thermal conductivity and bulk-like electrical properties. Along this line, a high thermoelectric figure of merit (ZT) is also anticipated for other nanoporous thin films, whose bulk counterparts possess superior electrical properties but also high lattice thermal conductivities. Numerous thermoelectric studies have been carried out on Si-based nanoporous thin films, whereas cost-effective nitrides and oxides are not systematically studied for similar thermoelectric benefits. In this work, the cross-plane thermal conductivities of nanoporous In Ga N thin films with varied porous patterns were measured with the time-domain thermoreflectance technique. These alloys are suggested to have better electrical properties than conventional Si Ge alloys; however, a high ZT is hindered by their intrinsically high lattice thermal conductivity, which can be addressed by introducing nanopores to scatter phonons. In contrast to previous studies using dry-etched nanopores with amorphous pore edges, the measured nanoporous thin films of this work are directly grown on a patterned sapphire substrate to minimize the structural damage by dry etching. This removes the uncertainty in the phonon transport analysis due to amorphous pore edges. Based on the measurement results, remarkable phonon size effects can be found for a thin film with periodic 300-nm-diameter pores of different patterns. This indicates that a significant amount of heat inside these alloys is still carried by phonons with ~300 nm or longer mean free paths. Our studies provide important guidance for ZT enhancement in alloys of nitrides and similar oxides.

关键词： nanoporous film     thermoelectrics     phonon     mean free path     diffusive scattering    

HTML PDF 收藏

标题 作者 时间 类型 操作

Fracture model for the prediction of the electrical percolation threshold in CNTs/Polymer composites

Yang SHEN, Pengfei HE, Xiaoying ZHUANG

期刊论文

Activated carbon induced oxygen vacancies-engineered nickel ferrite with enhanced conductivity for supercapacitor

期刊论文

Permeability and thermal conductivity of host compressed natural graphite for consolidated activated

Bo TIAN, Liwei WANG, Zhequan JIN, Ruzhu WANG

期刊论文

Equivalent thermal conductivity of heat pipes

LU Zesheng, MA Binghui

期刊论文

Tailoring electrical conductivity of two dimensional nanomaterials using plasma for edge electronics:

Aswathy Vasudevan, Vasyl Shvalya, Aleksander Zidanšek, Uroš Cvelbar

期刊论文

Modeling of ion conductivity in Nafion membranes

YANG Zhen, PENG Xiaofeng, WANG Buxuan, DUAN Yuanyuan, LEE Duujong

期刊论文

Techno-economic analysis of the adoption of electric vehicles

Donald KENNEDY, Simon P. PHILBIN

期刊论文

phosphorus-nitrogen based flame retardant and multi-walled carbon nanotubes for enhanced electrical conductivity

Yong Luo, Yuhui Xie, Renjie Chen, Ruizhi Zheng, Hua Wu, Xinxin Sheng, Delong Xie, Yi Mei

期刊论文

Stem cell niches and endogenous electric fields in tissue repair

null

期刊论文

Characterization of 3D microstructure, thermal conductivity, and heat flow of cement-based foam using

期刊论文

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced conductivity

期刊论文

Recent progress in electric-field assisted combustion: a brief review

期刊论文

Design and characteristics of electric supercharger for diesel engine acceleration by additional rapid

YAO Chun-de, ZHOU Hong-xiu

期刊论文

Lightweight design of an electric bus body structure with analytical target cascading

期刊论文

Largely reduced cross-plane thermal conductivity of nanoporous In

Dongchao XU, Quan WANG, Xuewang WU, Jie ZHU, Hongbo ZHAO, Bo XIAO, Xiaojia WANG, Xiaoliang WANG, Qing HAO

期刊论文