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Nondoped-type White Organic Light-Emitting Diode Using Star-Shaped Hexafluorenylbenzene as an Energy Transfer Layer
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作者 Jun-sheng Yu Tao Ma +2 位作者 Shuang-ling Lou Ya-dong Jiang Qing Zhang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2008年第5期500-504,共5页
有 indium-tin-oxide ( ITO )的结构的白器官的轻射出的二极管( WOLED ) /N ,N'-bis-( 1-naphthyl ) -N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine ( NPB ) /1,2,3,4,5,6-hexakis ( 9,9-diethyl-9H-fluoren-2-yl )苯(... 有 indium-tin-oxide ( ITO )的结构的白器官的轻射出的二极管( WOLED ) /N ,N'-bis-( 1-naphthyl ) -N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine ( NPB ) /1,2,3,4,5,6-hexakis ( 9,9-diethyl-9H-fluoren-2-yl )苯( HKEthFLYPh ) /5,6,11,12 -tetraphenylnaphtacene ( rubrene ) /tris ( 8-hydroxyquinoline )铝( Alq <SUB>3</SUB>)/Mg:Ag 被真空免职方法制作,在哪个新奇塑造星的 hexafluorenylbenzene HKEthFLYPh 被用作精力转移层,并且 rubrene 的极端薄层作为黄轻射出的层在 HKEthFLYPh 和 Alq <SUB>3</SUB>层之间被插入而不是使用一个费时间的做过程。有委员会共产国际歌 De L'Eclairage (CIE ) 的相当纯的 WOLED 协调(0.32, 0.33 ) 当 rubrene 的厚度是 0.3 nm,和光谱时,被获得对应用电压感觉迟钝。设备在 18 V 产出 4816 cd/m <SUP>2</SUP> 的最大的发光性。 展开更多
关键词 有机物 发光二极管 能量转移 化学分析
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Cross-linked polyelectrolyte reinforced SnO_(2)electron transport layer for robust flexible perovskite solar cells
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作者 Zhihao Li Zhi Wan +7 位作者 Chunmei Jia Meng Zhang Meihe Zhang Jiayi Xue Jianghua Shen Can Li Chao Zhang Zhen Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期335-342,I0010,共9页
SnO_(2)electron transport layer(ETL)is a vital component in perovskite solar cells(PSCs),due to its excellent photoelectric properties and facile fabrication process.In this study,we synthesized a water-soluble and ad... SnO_(2)electron transport layer(ETL)is a vital component in perovskite solar cells(PSCs),due to its excellent photoelectric properties and facile fabrication process.In this study,we synthesized a water-soluble and adhesive polyelectrolyte with ethanolamine(EA)and poly-acrylic acid(PAA).The linear PAA was crosslinked by EA,forming a 3D network that stabilized the SnO_(2)nanoparticle dispersion.An organic–inorganic hybrid ETL is developed by introducing the cross-linked PAA-EA into SnO_(2)ETL,which prevents nano particle agglomeration and facilitates uniform SnO_(2)film formation with fewer defects.Additionally,the PAA-EA-modified SnO_(2)facilitated a uniform and compact perovskite film,enhancing the interface contact and carrier transport.Consequently,the PAA-EA-modified PSCs exhibited excellent PCE of 24.34%and 22.88%with high reproducibility for areas of 0.045 and 1.00 cm~2,respectively.Notably,owing to structure reinforce effect of PAA-EA in SnO_(2)ETL,flexible device demonstrated an impressive PCE of 23.34%while maintaining 90.1%of the initial PCE after 10,000 bending cycles with a bending radius of 5 mm.This successful approach of polyelectrolyte reinforced hybrid organic–inorganic ETL displays great potential for flexible,large-area PSCs application. 展开更多
关键词 POLYELECTROLYTE CROSS-LINK Tin oxide Electron transfer layer Flexible solar cells
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A Simplified Scheme of the Generalized Layered Radiative Transfer Model 被引量:2
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作者 戴秋丹 孙菽芬 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第2期213-226,共14页
In this paper, firstly, a simplified version (SGRTM) of the generalized layered radiative transfer model (GRTM) within the canopy, developed by us, is presented. It reduces the information requirement of inputted ... In this paper, firstly, a simplified version (SGRTM) of the generalized layered radiative transfer model (GRTM) within the canopy, developed by us, is presented. It reduces the information requirement of inputted sky diffuse radiation, as well as of canopy morphology, and in turn saves computer resources. Results from the SGRTM agree perfectly with those of the GRTM. Secondly, by applying the linear superposition principle of the optics and by using the basic solutions of the GRTM for radiative transfer within the canopy under the condition of assumed zero soil reflectance, two sets of explicit analytical solutions of radiative transfer within the canopy with any soil reflectance magnitude are derived: one for incident diffuse, and the other for direct beam radiation. The explicit analytical solutions need two sets of basic solutions of canopy reflectance and transmittance under zero soil reflectance, run by the model for both diffuse and direct beam radiation. One set of basic solutions is the canopy reflectance αf (written as α1 for direct beam radiation) and transmittance βf (written as β1 for direction beam radiation) with zero soil reflectance for the downward radiation from above the canopy (i.e. sky), and the other set is the canopy reflectance (αb) and transmittance βb for the upward radiation from below the canopy (i.e., ground). Under the condition of the same plant architecture in the vertical layers, and the same leaf adaxial and abaxial optical properties in the canopies for the uniform diffuse radiation, the explicit solutions need only one set of basic solutions, because under this condition the two basic solutions are equal, i.e., αf = αb and βf = βb. Using the explicit analytical solutions, the fractions of any kind of incident solar radiation reflected from (defined as surface albedo, or canopy reflectance), transmitted through (defined as canopy transmittance), and absorbed by (defined as canopy absorptance) the canopy and other properties pertinent to the radiative transfer within the canopy can be estimated easily on the ground surface below the canopy (soil or snow surface) with any reflectance magnitudes. The simplified transfer model is proven to have a similar accuracy compared to the detailed model, as well as very efficient computing. 展开更多
关键词 generalized layered canopy radiative transfer model simplified model analytical solutions basic solutions adaxial abaxial leaf optical properties
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Effect of SDBS on interfacial electron transfer at the liquid/liquid interface by thin layer method 被引量:1
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作者 Xiu Hui Liu Cun Wu Dong Kai Zhang Fu Peng Zhi Zhen Ding Xiao Quan Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1115-1118,共4页
The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate (SDBS) on electron transfer (ET) reaction between ferricyanide aqueous solution and decamethylferrocene (DMFc) located on the adjacen... The effect of an adsorbed anionic surfactant sodium dodecyl benzene sulfonate (SDBS) on electron transfer (ET) reaction between ferricyanide aqueous solution and decamethylferrocene (DMFc) located on the adjacent organic phase was investigated for the first time by thin layer method. The adsorption of SDBS at the interface resulted in a decay in the cathodic plateau current of bimolecular reaction with increasing concentrations of SDBS in aqueous phase. However, the rate constant of electron transfer (ket) increased monotonically as the SDBS concentrations increased from 0 to 200 p, moFL. The experimental results showed that SDBS formed patches on the interface and influenced the structure of electrical double layer. 2009 Xiao Quan Lu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Anionic surfactant Liquid/liquid interface Electron transfer Thin layer method
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Experimental study on convection heat transfer and air drag in sinter layer 被引量:2
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作者 潘利生 魏小林 +2 位作者 彭岩 时小宝 刘怀亮 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2841-2848,共8页
Convection heat transfer coefficient and air pressure drop in sinter layer are important factors for the design of sinter cooling craft. Due to the lack of necessary data, the two parameters are studied by experimenta... Convection heat transfer coefficient and air pressure drop in sinter layer are important factors for the design of sinter cooling craft. Due to the lack of necessary data, the two parameters are studied by experimental method. The experimental results show that heat conduction of sinter impacts the measurement of convection heat transfer coefficient. Convection heat transfer increases with the increase of air volumetric flow rate. Sinter layer without small particles(sample I) gives higher convection heat transfer coefficient than that with small particles(sample II). Under the considered conditions, volumetric convection heat transfer coefficient is in the range of 400-1800 W/(m3·°C). Air pressure drop in sinter layer increases with the increase of normal superficial velocity, as well as with the rise of air temperature. Additionally, air pressure drop also depends on sinter particle size distribution. In considered experimental conditions, pressure drop in sinter sample II is 2-3 times that in sinter sample I, which resulted from 17% small scale particles in sinter sample II. 展开更多
关键词 对流换热系数 空气阻力 实验条件 烧结层 体积流量 小颗粒 工艺设计 空气压力
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Unsteady boundary layer flow and heat transfer over an exponentially shrinking sheet with suction in a copper-water nanofluid 被引量:6
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作者 Aurang Zaib Krishnendu Bhattacharyya Sharidan Shafie 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4856-4863,共8页
An analysis of unsteady boundary layer flow and heat transfer over an exponentially shrinking porous sheet filled with a copper-water nanofluid is presented.Water is treated as a base fluid.In the investigation,non-un... An analysis of unsteady boundary layer flow and heat transfer over an exponentially shrinking porous sheet filled with a copper-water nanofluid is presented.Water is treated as a base fluid.In the investigation,non-uniform mass suction through the porous sheet is considered.Using Keller-box method the transformed equations are solved numerically.The results of skin friction coefficient,the local Nusselt number as well as the velocity and temperature profiles are presented for different flow parameters.The results showed that the dual non-similar solutions exist only when certain amount of mass suction is applied through the porous sheet for various unsteady parameters and nanoparticle volume fractions.The ranges of suction where dual non-similar solution exists,become larger when values of unsteady parameter as well as nanoparticle volume fraction increase.So,due to unsteadiness of flow dynamics and the presence of nanoparticles in flow field,the requirement of mass suction for existence of solution of boundary layer flow past an exponentially shrinking sheet is less.Furthermore,the velocity boundary layer thickness decreases and thermal boundary layer thickness increases with increasing of nanoparticle volume fraction in both non-similar solutions.Whereas,for stronger mass suction,the velocity boundary layer thickness becomes thinner for the first solution and the effect is opposite in the case of second solution.The temperature inside the boundary layer increases with nanoparticle volume fraction and decreases with mass suction.So,for the unsteadiness and for the presence of nanoparticles,the flow separation is delayed to some extent. 展开更多
关键词 unsteady boundary layer heat transfer NANOFLUID exponentially shrinking sheet dual non-similar solutions
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Fabrication of seeded substrates for layer transferrable silicon films
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作者 李纪周 张伟 +4 位作者 鄢靖源 王聪 陈宏飞 陈小源 刘东方 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期450-454,共5页
The layer transfer process is one of the most promising methods for low-cost and highly-efficient solar cells, in which transferrable mono-crystalline silicon thin wafers or films can be produced directly from gaseous... The layer transfer process is one of the most promising methods for low-cost and highly-efficient solar cells, in which transferrable mono-crystalline silicon thin wafers or films can be produced directly from gaseous feed-stocks. In this work, we show an approach to preparing seeded substrates for layer-transferrable silicon films. The commercial silicon wafers are used as mother substrates, on which periodically patterned silicon rod arrays are fabricated, and all of the surfaces of the wafers and rods are sheathed by thermal silicon oxide. Thermal evaporated aluminum film is used to fill the gaps between the rods and as the stiff mask, while polymethyl methacrylate (PMMA) and photoresist are used as the soft mask to seal the gap between the filled aluminum and the rods. Under the joint resist of the stiff and soft masks, the oxide on the rod head is selectively removed by wet etching and the seed site is formed on the rod head. The seeded substrate is obtained after the removal of the masks. This joint mask technique will promote the endeavor of the exploration of mechanically stable, unlimitedly reusable substrates for the kerfless technology. 展开更多
关键词 seeded substrate layer transfer joint mask FILLER silicon film
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Numerical Simulation of Heat Transfer Characteristics of Horizontal Ground Heat Exchanger in Frozen Soil Layer 被引量:2
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作者 王华军 赵军 《Transactions of Tianjin University》 EI CAS 2007年第3期200-204,共5页
A simplified numerical model of heat transfer characteristics of horizontal ground heat exchanger (GHE) in the frozen soil layer is presented and the steady-state distribution of temperature field is simulated. Numeri... A simplified numerical model of heat transfer characteristics of horizontal ground heat exchanger (GHE) in the frozen soil layer is presented and the steady-state distribution of temperature field is simulated. Numerical results show that the frozen depth mainly depends on the soil′s moisture content and ambient temperature. The heat transfer loss of horizontal GHE tends to grow with the increase of the soil′s moisture content and the decrease of ambient temperature. Backfilled materials with optimal thermal conductivity can reduce the thermal loss effectively in the frozen soil. The applicability of the Chinese national standard “Technical Code for Ground Source Heat Pump (GB 50366-2005)” is verified. For a ground source heat pump project, the feasible layout of horizontal GHE should be determined based on the integration of the soil′s structure, backfilled materials, weather data, and economic analysis. 展开更多
关键词 地面水 散热器 地面温度 热度传播
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Numerical Simulation of the Marangoni Effect with Interphase Mass Transfer Between Two Planar Liquid Layers 被引量:3
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作者 毛在砂 陆平 +1 位作者 张广积 杨超 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第2期161-170,共10页
传质在在二不溶混的液体之间的接口导致的 Marangoni 效果在实验室和溶剂萃取的工业操作上显示重要影响。在二个液层系统的二维的 Marangoni 效果的系统的数字研究被进行。界面张力对溶质集中的线性关系在两个阶段为液体流动和传质被合... 传质在在二不溶混的液体之间的接口导致的 Marangoni 效果在实验室和溶剂萃取的工业操作上显示重要影响。在二个液层系统的二维的 Marangoni 效果的系统的数字研究被进行。界面张力对溶质集中的线性关系在两个阶段为液体流动和传质被合并到数学模型财务。典型盒子由 Sternling 与 Scriven 分析了(AIChE J. , 1959 ) 使用线性不稳定性理论被在理论之间的有限差别方法和好同意模仿,数字模拟被观察。模拟建议 Marangoni 传送对流需要某些时间在力量和规模足够地发展提高分裂期间传质, Marangoni 效果动态、短暂,并且只要传质推动力被使经常,在某稳定的水平留下。什么时候某些水平砍作为在实际意义的大多数情况中在接口被强加,当 shear 逐渐地被增加, Marangoni 效果稍微,但是日益增多地被压制。Marangoni 效果的现在的二维的模拟提供某卓见进内在的机制并且也在真实世界上并且在化学工程应用程序的三维的 Marangoni 效果的进一步理论的学习的基础。 展开更多
关键词 两液层体系 传质 MARANGONI效应 数值模拟
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Boundary Layer Flow of an Unsteady Dusty Fluid and Heat Transfer Over a Stretching Sheet with Non-Uniform Heat Source/Sink 被引量:1
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作者 Bijjanal J. Gireesha Govinakovi S. Roopa Channabasappa S. Bagewadi 《Engineering(科研)》 2011年第7期726-735,共10页
An analysis has been carried out to study the effect of hydrodynamic laminar boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface in the presence of non-uniform heat source/sink. ... An analysis has been carried out to study the effect of hydrodynamic laminar boundary layer flow and heat transfer of a dusty fluid over an unsteady stretching surface in the presence of non-uniform heat source/sink. Heat transfer characteristics are examined for two different kinds of boundary conditions, namely 1) variable wall temperature and 2) variable heat flux. The governing partial differential equations are transformed to system of ordinary differential equations. These equations are solved numerically by applying RKF-45 method. The effects of various physical parameters such as magnetic parameter, dust interaction parameter, number density, Prandtl number, Eckert number, heat source/sink parameter and unsteadiness parameter on velocity and temperature profiles are studied. 展开更多
关键词 UNSTEADY Flow HEAT transfer Boundary layer Flow Stretching Surface DUSTY FLUID Fluid-Particle Interaction Parameter and NON-UNIFORM HEAT Source/Sink
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Heat transfer for boundary layers with cross flow
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作者 Krishnendu Bhattacharyya Ioan Pop 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第2期327-332,共6页
An analysis is presented to study the dual nature of solutions for the forced convective boundary layer flow and heat transfer in a cross flow with viscous dissipation terms in the energy equation. The governing equat... An analysis is presented to study the dual nature of solutions for the forced convective boundary layer flow and heat transfer in a cross flow with viscous dissipation terms in the energy equation. The governing equations are transformed into a set of three self-similar ordinary differential equations by similarity transformations. These equations are solved numerically using the very efficient shooting method. This study reveals that the dual solutions of the transformed similarity equations for velocity and temperature distributions exist for certain values of the moving parameter, Prandtl number, and Eckert numbers. The reverse heat flux is observed for larger Eckert numbers; that is, heat absorption at the wall occurs. 展开更多
关键词 heat transfer boundary layer cross flow viscous dissipation dual solutions
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Zero-Magnetic-Field Oscillation of Spin Transfer Nano-Oscillator with a Second-Order-Perpendicular-Anisotropy Free Layer
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作者 郭园园 赵飞飞 +1 位作者 薛海斌 刘喆颉 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期107-110,共4页
The zero-magnetic-field oscillation behavior of spin torque nano-oscillator (STNO) with a perpendicularly mag- netized free layer with second-order uniaxial anisotropy is studied theoretically based on the Landau-Li... The zero-magnetic-field oscillation behavior of spin torque nano-oscillator (STNO) with a perpendicularly mag- netized free layer with second-order uniaxial anisotropy is studied theoretically based on the Landau-Lifshitz- Cilbert-Slonczewski equation. It is demonstrated numerically that the second-order uniaxial anisotropy plays a significant role in the occurrence of a zero-magnetic-field steady-state precession, which can be understood in terms of the energy balance between the energy accumulation due to the spin torque and the energy dissipation due to the Gilbert damping. In particular, a relatively large zero-magnetic-field-oscillation current region, in which the corresponding microwave frequency is increased while the threshold current still maintains an almost constant value, can be obtained by modulating the second-order uniaxial anisotropy of the free layer. These results suggest a tunable zero-magnetic-field STNO, and it may be a promising configuration for STNO's applications in future wireless communications. 展开更多
关键词 of on in is it as Zero-Magnetic-Field Oscillation of Spin transfer Nano-Oscillator with a Second-Order-Perpendicular-Anisotropy Free layer with
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Effects of Solid Matrix and Porosity of Porous Medium on Heat Transfer of Marangoni Boundary Layer Flow Saturated with Power-Law Nanofluids
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作者 陈晖 肖天丽 +1 位作者 陈嘉阳 沈明 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期80-84,共5页
The effect of the solid matrix and porosity of the porous medium are first introduced to the study of power-law nanofluids, and the Marangoni boundary layer flow with heat generation is investigated. Two cases of soli... The effect of the solid matrix and porosity of the porous medium are first introduced to the study of power-law nanofluids, and the Marangoni boundary layer flow with heat generation is investigated. Two cases of solid matrix of porous medium including glass balls and aluminum foam are considered. The governing partial differential equations are simplified by dimensionless variables and similarity transformations, and are solved numerically by using a shooting method with the fourth-fifth-order Runge-Kutta integration technique. It is indicated that the increase of the porosity leads to the enhancement of heat transfer in the surface of the Marangoni boundary layer flow. 展开更多
关键词 of is as Effects of Solid Matrix and Porosity of Porous Medium on Heat transfer of Marangoni Boundary layer Flow Saturated with Power-Law Nanofluids in with on
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Analytical solutions to a compressible boundary layer problem with heat transfer 被引量:1
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作者 LiancunZheng XinxinZhang JichengHe 《Journal of University of Science and Technology Beijing》 CSCD 2004年第2期120-122,共3页
The problem of momentum and heat transfer in a compressible boundary layerbehind a thin expansion wave was solved by the application of the similarity transformation and theshooting technique. Utilizing the analytical... The problem of momentum and heat transfer in a compressible boundary layerbehind a thin expansion wave was solved by the application of the similarity transformation and theshooting technique. Utilizing the analytical expression of a two-point boundary value problem formomentum transfer, the energy boundary layer solution was represented as a function of thedimensionless velocity, and as the parameters of the Prandtl number, the velocity ratio, and thetemperature ratio. 展开更多
关键词 compressible boundary layer momentum and heat transfer analytical solution
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A Two-Layer Model for Superposed Electrified Maxwell Fluids in Presence of Heat Transfer 被引量:1
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作者 Kadry Zakaria Magdy A. Sirwah Sameh A. Alkharashi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第6期1077-1094,共18页
基于一个 modified-DarcyMaxwell 模型,二维,不可压缩并且二围住的层的热转移流动,通过触电的麦克斯韦,在多孔的媒介的液体被执行。为在一个电场下面的不稳定性的驱动力,在免费费用上施加的静电的力量在划分接口被积累。正常模式... 基于一个 modified-DarcyMaxwell 模型,二维,不可压缩并且二围住的层的热转移流动,通过触电的麦克斯韦,在多孔的媒介的液体被执行。为在一个电场下面的不稳定性的驱动力,在免费费用上施加的静电的力量在划分接口被积累。正常模式分析被认为学习骚乱层的线性稳定性。有边界条件的运动的线性化的方程的答案导致在生长率和波浪数字之间的一种含蓄的分散关系。这些方程是由威伯数字,雷纳兹数字, Marangoni 数字,无尺寸的传导性,和无尺寸的电的潜力的 parameterized。长波浪的格界面的稳定性被学习了。稳定性标准在在哪个稳定性,图被获得理论上被执行。在限制的格中,一些以前出版的结果能被认为我们的结果的格同样特别。雷纳兹数字在稳定性标准起一个使动摇的作用,这被发现,当抑制影响为增加 Marangoni 数字和麦克斯韦松驰时间被观察时。 展开更多
关键词 麦克斯韦 电气化 传热模型 MARANGONI 流体 Maxwell模型 叠加 静电作用力
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Effects of Hall Current on MHD Boundary Layer Second-Order Viscoelastic Fluid Flow Induced by a Continuous Surface with Heat Transfer
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作者 Haider Zaman Murad Ali Shah +1 位作者 Farhan Khan Qaiser Javed 《American Journal of Computational Mathematics》 2014年第3期143-152,共10页
Effects of Hall current on heat transfer and magnetohydrodynamic (MHD) boundary layer flow induced by a continuous surface in a parallel free stream of a second-order viscoelastic fluid are studied for uniform suction... Effects of Hall current on heat transfer and magnetohydrodynamic (MHD) boundary layer flow induced by a continuous surface in a parallel free stream of a second-order viscoelastic fluid are studied for uniform suction/injection by taking viscous dissipation into account. Complex nonsimilar solutions to the stream function and temperature are developed by means of an elegant technique, known as homotopy analysis method (HAM). Convergence of the solutions is ensured with the help of -curves. Graphical and tabular results for the effects of Hall current reveal that it has a significant influence on: complex velocity, complex temperature, magnitude of the shear stress at the surface, magnitude of the rate of heat transfer at the surface and on boundary layer thickness. 展开更多
关键词 HALL CURRENTS Heat transfer Boundary layer Complex Nonsimilar Solutions HAM
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Experimental Study of Heat Transfer in a Real Scale Building Incorporating PCM in the Air Layer of the Vertical Walls
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作者 Zahra Najam Mustapha El Alami Mostafa Najam 《Journal of Power and Energy Engineering》 2019年第5期14-25,共12页
The purpose of this paper is to study the energy efficiency of a local living space exposed to solar radiation in the subtropical climate of Casablanca. The study was mainly focused on the contribution of a phase chan... The purpose of this paper is to study the energy efficiency of a local living space exposed to solar radiation in the subtropical climate of Casablanca. The study was mainly focused on the contribution of a phase change material (PCM), inserted into a 7-cm thick air layer of a double brick wall, in two different locations. We note that the experimental study was conducted using two real-scale test cavities, located in the Faculty of Science Ain Chock-Casablanca. Two PCM mounting methods were used for the south and west walls, in order to test its energy efficiency as a storage and retrieval means of the solar flux coming from the outside. In the case of the southern wall, the PCM is put directly on the internal side of the outside part of the double wall (Case 1). For the west wall, the PCM is placed 1.2 cm away from the internal side of the outer part of the double wall (Case 2). The first result shows that the PCM placed to the wall allows storing the solar heat during the day and releasing it to the outside of the building at night. While in the second case, the PCM keeps the heat stored day and night. 展开更多
关键词 Experimental Study Heat transfer PCM Air layer Real-Scale BUILDING
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Boundary Layer Stagnation-Point Slip Flow and Heat Transfer towards a Shrinking/Stretching Cylinder over a Permeable Surface
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作者 Nor Azian Aini Mat Norihan Md. Arifin +1 位作者 Roslinda Nazar Norfifah Bachok 《Applied Mathematics》 2015年第3期466-475,共10页
In this paper, the boundary layer stagnation-point slip flow and heat transfer towards a shrinking/stretching cylinder over a permeable surface is considered. The governing equations are first transformed into a syste... In this paper, the boundary layer stagnation-point slip flow and heat transfer towards a shrinking/stretching cylinder over a permeable surface is considered. The governing equations are first transformed into a system of non-dimensional equations via the non-dimensional variables, and then into self-similar ordinary differential equations before they are solved numerically using the shooting method. Numerical results are obtained for the skin friction coefficient and the local Nusselt number as well as the velocity and temperature profiles for some values of the governing parameters, namely the velocity slip parameter (α), the thermal slip parameter (β), the curvature parameter (γ) and the velocity ratio parameter (c/a). The physical quantities of interest are the skin friction coefficient and the local Nusselt number measured by f’’(0) and –θ’(0), respectively. The numerical results show that the velocity slip parameter α increases the heat transfer rate at the surface, while the thermal slip parameter β decreases it. On the other hand, increasing the velocity slip parameter α causes the decrease in the flow velocity. Further, it is found that the solutions for a shrinking cylinder (c/ac/a>0) case. Finally, it is also found that the values of f’’(0) and –θ’(0) increase as the curvature parameter γ increases. 展开更多
关键词 Boundary layer Heat transfer Numerical Solution Shrinking/Stretching CYLINDER SLIP Flow Stagnation-Point Suction/Injection
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Droplet transfer behavior of the stainless steel coated electrode with double-layer coating
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作者 孙咸 马成勇 +1 位作者 王宝 张汉谦 《China Welding》 EI CAS 2002年第2期124-129,共6页
In this paper, the droplet transfer behavior of the stainless steel coated electrode with double layer coating is researched by means of those experimental methods, such as high speed camera, collecting droplet in wa... In this paper, the droplet transfer behavior of the stainless steel coated electrode with double layer coating is researched by means of those experimental methods, such as high speed camera, collecting droplet in water, surfacing on the steel plate et al. The results show that the droplet transfer indexes of coated electrode are mainly controlled by the size of droplet, which affects the transfer behavior of droplet. The distribution characteristic of the droplet size of the electrode affects the numerical relationship among droplet transfer indexes. The metallurgical process of the coated electrode with double layer coating is carried out continuously in different zones. The main reason for the coated electrode with double layer coating gaining excellent usability quality is that the droplets realize the 'quasi flux wall guided transfer pattern'. 展开更多
关键词 droplet transfer stainless steel coated electrode double layer coating
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Influence of Chemical Reaction and Thermal Radiation on MHD Boundary Layer Flow and Heat Transfer of a Nanofluid over an Exponentially Stretching Sheet 被引量:1
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作者 N. G. Rudraswamy B. J. Gireesha 《Journal of Applied Mathematics and Physics》 2014年第2期24-32,共9页
In the present article a numerical analysis has been carried out to study the boundary layer flow behavior and heat transfer characteristics of a nanofluid over an exponential stretching sheet. By assuming the stretch... In the present article a numerical analysis has been carried out to study the boundary layer flow behavior and heat transfer characteristics of a nanofluid over an exponential stretching sheet. By assuming the stretching sheet to be impermeable, the effect of chemical reaction, thermal radiation, thermopherosis, Brownian motion and suction parameters in the presence of uniform magnetic field on heat and mass transfer are addressed. The governing system of equations is transformed into coupled nonlinear ordinary differential equations using suitable similarity transformations. The transformed equations are then solved numerically using the well known Runge-Kutta-Fehlberg method of fourth-fifth order. A detailed parametric study is performed to access the influence of the physical parameters on longitudinal velocity, temperature and nanoparticle volume fraction profiles as well as the local skin-friction coefficient, local Nusselt number and the local Sherwood number and the results are presented in both graphical and tabular forms. 展开更多
关键词 NANOFLUID EXPONENTIALLY STRETCHING Sheet Chemical Reaction Thermal Radiation Boundary layer Flow Heat and Mass transfer
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