检索结果-南通市图书馆

Journal of Power and Energy Engineering 2019年第11期7卷 15-27页

作者： Kashif Ali Yanbing Jia Muhammad Abbas Syed Arslan Bukhari 79 West Yingze Street Taiyuan University of Technology Taiyuan China

Environmental conditions such as wind, temperature and humidity affect the amount of solar irradiance received by the photovoltaic (PV) cells and thus have a significant effect on the PV output efficiency. This paper aims to analyze the power efficiency of polycrystalline Silicon solar cells under China’s weather considering these environmental conditions. Performance of the polycrystalline solar panel is analyzed through eight months of data emphasizing the maximum, average and minimum temperature acquired from a solar power plant installed at Taiyuan University of technology, China consisting of 78 PV panels with a total rated capacity of 20 KW and average module efficiency of 16.56% at an ambient temperature of 25°. The results of our practical investigations show that polycrystalline solar cells in October yield the best monthly average efficiency of 35.6% at an average temperature and humidity level of 14°C and 44%. In comparison to a maximum temperature of 27°C and humidity of 66% in summer, the efficiency is found to drop by 5%. Also, the power produced in winter at minimum temperature and the efficiency showed a decline of 15% compared to that of October. Consequently, this investigation leads to a conclusion that the increase in temperature and humidity together is found to have a negative effect on the efficiency whereas the increase in irradiance and wind speed showed an improvement in the output power of the polycrystalline solar cells.

关键词： Efficiency polycrystalline Photovoltaics Weather Effects

An atomic level study on the out-of-plane thermal conductivity of polycrystalline argon nanofilm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science Bulletin 2012年第Z1期 296-300页

作者： JU ShengHong & LIANG XinGang* Department of Engineering Mechanics,Key Laboratory for Thermal Science and Power Engineering of Ministry of Education,Tsinghua University,Beijing 100084,China

At present,there have been few direct molecular dynamics simulations on the thermal conductivity of polycrystalline *** this paper,we generate polycrystalline argon nanofilms with random grain shape using the three-dimensional Voronoi tessellation *** calculate the out-of-plane thermal conductivity of a polycrystalline argon nanofilm at different temperatures and film thicknesses by the Muller-Plathe *** results indicate that the polycrystalline thermal conductivity is lower than that of the bulk single crystal and the single-crystal nanofilm of *** can be attributed to the phonon mean-free-path limit imposed by the average grain size as well as the grain boundary thermal resistance due to the existence many grain boundaries in polycrystalline ***,the out-of-plane thermal conductivity of the polycrystalline argon nanofilm is insensitive to temperature and film thickness,and is mainly dominated by the grain size,which is quite different from the case of single-crystal nanofilms.

关键词： thermal conductivity polycrystalline argon nanofilm molecular dynamics simulation

Forming Stages of polycrystalline TiN Films Depending on the Nitrogen Concentration in Mixed Gas

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2011年第1期2卷 6-13页

作者： Anna L. Kameneva 不详

The influence of nitrogen concentration in mixed gas on temperature conditions, structure and phase composition of the TiN film deposited by arc spraying has been investigated. By electron microscopic investigations and X-ray diffraction phase analysis was recognized forming stages and structuring process of the film with main cubic phase (111) TiN. It was discovered that forming stages and process of structuring of ion-plasma TiN films are affected by both film temperature and its rate of heating.

关键词： polycrystalline TiN Film Arc Spraying Temperature Conditions Forming Stages Structure and Phase Modification

Molecular Dynamics Simulation of Grain Refinement in a polycrystalline Material under Severe Compressive Deformation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2017年第12期8卷 918-932页

作者： Takuya Uehara Department of Mechanical Systems Engineering Yamagata University Yonezawa Japan

Grain refinement in a polycrystalline material resulting from severe compressive deformation was simulated using molecular dynamics. A simplified model with four square grains surrounded by periodic boundaries was prepared, and compressive deformation was imposed by shortening the length in the y direction. The model first deformed elastically, and the compressive stress increased monotonically. Inelastic deformation was then initiated, and the stress decreased drastically. At that moment, dislocation or slip was initiated at the grain boundaries or triple junction and then spread within the grains. New grain boundaries were then generated in some of the grains, and sub-grains appeared. Finally, a microstructure with refined grains was obtained. This process was simulated using two types of grain arrangements and three different combinations of crystal orientations. Grain refinement generally proceeded in a similar fashion in each scenario, whereas the detailed inelastic deformation and grain refinement behavior depended on the initial microstructure.

关键词： Molecular Dynamics polycrystalline Material Microstructure Grain Boundary Grain Refinement Severe Plastic Deformation Computer Simulation

Effect of the Heat Treatments on the Dopes Segregation in polycrystalline Silicon Films

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Physics 2012年第9期3卷 1046-1049页

作者： Salima Silini Baghdadi Chouial Bouzid Hadjoudja Ouissem Benhalima Sana Yousfi Allaoua Chibani Laboratory of Semiconductors Department of Physics University Badji Mokhtar Annaba Algeria

In this work we are interested in studying the effect of the heat treatments on the dopant segregation at the grain boundaries in the polycrystalline silicon films. The obtained results have shown that the heat treatments reduce the number of segregation sites at the grains boundaries, and consequently they limit the structural changes that can appear there and the quantity of the dope atoms that can accumulate in these boundaries. In addition they are more and more dopant that are found inside the grains when the temperature of the heat treatment increases. On the other hand, we established that the arsenic atoms have a strong tendency to the segregation than the boron atoms, and we have noticed a strong migration of arsenic atoms from the boundaries towards the grains under the effect of the heat treatments. It was also shown that the segregation of arsenic atoms at the grains boundaries is about 4 times higher than that of the boron atoms.

关键词： Segregation Grains Boundaries Heat Treatments polycrystalline Silicon

Switching Behaviour of polycrystalline Diamond Thin Film

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1993年第5期38卷 382-384页

作者：沈书泊张兵临何金田王建恩 Howard R.Shanks Moeljanto W.Leksono Bob Girvan Henan Fundamental and Applied Science Research Institute Zhengzhou University Zhengzhou 450052 PRC Microelectronics Research Center Iowa State University Ames Iowa USA

Switching phenomena in some semiconductor wafers and thin films were observed early. However, to our knowledge, there is no report about the switching behaviour of diamond thin film. Because the diamond thin film possesses a great number of good properties, such as wide band gap, high breakdown voltage, high electron mobilities and high electron saturation velocity, the investigation on the switching behaviour of diamond thin film will be of great value for achieving high voltage and high power switching devices. We

关键词： polycrystalline diamond thin film switching behaviour bistability.

维普期刊数据库

Hierarchical-vortex polarization domain pattern in nano polycrystalline ferroelectric

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Dielectrics 2022年第4期12卷 30-35页

作者： Zhiyong Huang Qinan Li Yin Liang Xiaoqiao He Jiagang Wu Haidong Fan Xiaobao Tian School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065P.R.China Department of Mechanics Sichuan UniversityChengdu 610065P.R.China Department of Civil Engineering Sichuan UniversityChengdu 610065P.R.China Department of Architecture and Civil Engineering City University of Hong Kong Tat Chee AvenueKowloonHong Kong Department of Materials Science Sichuan UniversityChengdu 610065P.R.China

Domain pattern is the carrier of electromechanical property.A novel domain pattern will open a gate for ferroelectric nano device.A distinctive topological domain pattern termed as hierarchical vortex(Hvo)has been found in polycrystalline ferroelectric based on the first-principles-based atomistic *** Hvo pattern displays a unique structure,which is a flux-closing vortex encircle an anti-vortex or a vortex and anti-vortex pair(VA).Each Hvo structure could be regarded as a single vortex to forming a vortex-anti-vortex pair with anti-vortex or forming a vortex-vortex array with the *** mechanism of HVo obtained in polycrystalline ferroelectric has been found that the grain boundary(GB)equals the domain wall when the first-order vortex is in the *** HVo will open a new view of the domain topology pattern and its evolution.

关键词： Domain pattern hierarchical vortex polycrystalline grain boundary self-consistent

A Label-Free Detection of Biomolecules Using Micromechanical Biosensors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第6期30卷 228-231页

作者： Meisam Omidi M.A.Malakoutian Mohammadmehdi Choolaei F.Oroojalian F.Haghiralsadat F.Yazdian Faculty of New Science and Technology University of TehranTehranIran Department of Electrical and Computer Engineering University of TehranTehranIran Department of Chemical Engineering South Tehran BranchIslamic Azad UniversityTehranIran

A Microcantilevers resonator is used to detect a protein biomarker called prostate specific antigen(PSA),which is associated with prostate *** concentrations of PSA in a buffer solution are detected as a function of deflection of the *** this purpose,we use a surface micromachined,antibody-coated polycrystalline silicon micromechanical cantilever *** have mass sensitivities of the order of 10–17 g/Hz,which result from their small *** matter allows them to detect an immobilized antibody monolayer corresponding to a mass of about 70 *** these devices,concentrations as low as 150 fg/mL,or 4.5 fM,could be detected from the realistic samples.

关键词： cantilever resonator polycrystalline

Negative gate bias stress effects on conduction and low frequency noise characteristics in p-type poly-Si thin-film transistors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2019年第8期28卷 397-402页

作者： Chao-Yang Han Yuan Liu Yu-Rong Liu Ya-Yi Chen Li Wang Rong-Sheng Chen School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510640China School of Automation Guangdong University of TechnologyGuangzhou 510006China Science and Technology on Reliability Physics and Application of Electronic Component Laboratory CEPREIGuangzhou 510610China

The instability of p-channel low-temperature polycrystalline silicon thin film transistors(poly-Si TFTs)is investigated under negative gate bias stress(NBS)in this ***,a series of negative bias stress experiments is performed,the significant degradation behaviors in current-voltage characteristics are *** the stress voltage decreases from-25 V to-37 V,the threshold voltage and the sub-threshold swing each show a continuous shift,which is induced by gate oxide trapped charges or interface ***,low frequency noise(LFN)values in poly-Si TFTs are measured before and after negative bias *** flat-band voltage spectral density is extracted,and the trap concentration located near the Si/SiO2 interface is also ***,the degradation mechanism is discussed based on the current-voltage and LFN results in poly-Si TFTs under NBS,finding out that Si-OH bonds may be broken and form Si*and negative charge OH-under negative bias stress,which is demonstrated by the proposed negative charge generation model.

关键词： polycrystalline silicon thin film transistor negative bias stress low frequency noise

维普期刊数据库

Structural features and thermoelectric performance of Sb- and Bi-doped Cu_(2)SnSe_(3) compounds

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2021年第9期40卷 2474-2485页

作者： Shu-Ping Deng Xian-Yan Jiang Li-Li Chen Zi-Ye Zhang Ning Qi Yi-Chu Wu Xin-Feng Tang Zhi-Quan Chen School of Physics and Technology Hubei Key Laboratory of Nuclear Solid State PhysicsWuhan UniversityWuhan 430072China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

In this paper, a series of Sb-doped and Bi-doped Cu_(2)Sn_(1-x)M_(x)Se_(3) samples(M = Sb, Bi) are prepared by vacuum melting combined with the spark plasma sintering process. The effects of different atomic doping amounts on their properties are discussed. Structural studies indicate that all obtained samples comprise a single Cu_(2)SnSe_(3) phase. Sb and Bi atoms are experimentally demonstrated to be efficient cation dopants for increasing the transport performance. Compared with that doping on the cation site,Bi doping is much more efficient in increasing the electron concentration of the Cu_(2)SnSe_(3) system. Ultimately, a high figure of merit of 0.36 is achieved in the Cu_(2)Sn_(0.94)Sb_(0.06) Se_(3) sample at 773 K due to the enhanced power factor and lowered lattice thermal conductivity,which are 1.73 times higher than those of the pure *** results provide an efficient approach to enhance thermoelectric performance via other doping atoms, which could also be applied to copper-based chalcogenide materials.

关键词： Thermoelectric properties Positron annihilation spectroscopy Ternary copper chalcogenide Structure features Doping polycrystalline

维普期刊数据库