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A modified streamwise body force model of fan with distorted inflow for rapid propulsion-airframe integrated simulation

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Chinese Journal of Aeronautics 2023年第12期36卷 202-213页

作者： Zhiping LI yafei zhang Tianyu PAN Jian zhang National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Streamwise Body Force Model(SBFM)could be used to simulate the force of blade on the airflow,resulting in rapid propulsion-airframe integrated ***,when subjected to inlet distortion,the upstream flow field of fan stage is redistributed,which causes inaccurate prediction of fan stage *** inspired by the upstream influence of compressor,this paper aims to present a modification strategy for SBFM method to predict the compressor performance under circumferential inlet distortion without any knowledge of compressor *** on the linearized motion equation,the Upstream Influence Model(UIM)is introduced to predict the upstream flow field *** the theoretical Mach number at Aerodynamic Interface Plane(AIP)position is calculated and selected to determine the corresponding body force coefficients based on the functional relationship between body force coefficients and Mach number,thus the upstream influence of compressor could be accurately quantified and the Modified Streamwise Body Force Model(MSBFM)could be *** studied cases are calculated with different methods and the upstream flow fields are *** prediction error of MSBFM method for compressor adiabatic efficiency is less than 3%,and the calculation efficiency is improved 20 times under the condition of ensuring computing *** MSBFM method has the potential for rapid propulsion-airframe integrated simulation.

关键词： Integrated simulation Streamwisebody force model Circumferential inletdistor-tion Upstream influence model Compressorperformance

Hydrogen Storage on Li Coated BC3 Honeycomb Sheet

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Chinese Journal of Chemistry 2017年第8期35卷 1329-1332页

作者： yafei zhang Xinlu Cheng Institution of Atomic and Molecule Physics Sichuan University Chengdu Sichuan 610065 China

Using density functional theory, we investigated the hydrogen storage capacity of Li coated BC3 honeycomb sheet. Our result indicates 18 H2 molecules can be adsorbed on BC3Li6 complex with a storage gravimetric density of 9.68 wt% and the average adsorption energy reaches 0.206 eV/H2. This is desirable for absorbing and desorbing H2 molecules at near ambient conditions.

关键词： hydrogen storage binding energy DFT calculations BC3 sheet adsorption

Surface Free Energies and Morphologies of Chemical Vapor Deposited Diamond Films

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Chinese Physics Letters 1994年第8期11卷 502-505页

作者： zhang yafei zhang Fangqing CHEN Guanghua Department of Physics Lanzhou UniversityLanzhou 730001

We have calculated the surface free energies of the chemical vapor deposited diamond crystals during the preparation process,using the model that a fraction of carbon dangling bonds on the growth surface are saturated by *** results show that the surface free energies of the three most energetically favored crystal planes,i.e.(100),(110)and(111),can be used to interpret the changes of predominant facets in the surface morphology from{100}to{111}with increasing substrate *** chemical vapor deposition conditions,it is found that the growth surfaces of diamond are more stable than that of graphite.

关键词： temperature Diamond surface

Chemotherapy suppresses SHH gene expression via a specific enhancer

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Journal of Genetics and Genomics 2023年第1期50卷 27-37页

作者： yafei zhang Jianqiong Lin Kaibin Yang Zhicao Yue Department of Cell Biology and Medical Genetics International Cancer Centerand Guangdong Key Laboratory for Genome Stability and Disease PreventionShenzhen University Medical SchoolShenzhenGuangdong 518060China

Sonic hedgehog(SHH)signaling is a key regulator of embryonic development and tissue homeostasis that is involved in gastrointestinal(GI)cancer *** of SHH gene expression is a paradigm of long-range enhancer *** the classical chemotherapy drug 5-fluorouracil(5FU)as an example,here we show that SHH gene expression is suppressed by *** is downstream of immediate early genes(IEGs),including Early growth response 1(Egr1).A specific 139 kb upstream enhancer is responsible for its *** down EGR1 expression or blocking its binding to this enhancer renders SHH unresponsive to *** further demonstrate that down-regulation of SHH expression does not depend on 5FU’s impact on nucleotide metabolism or DNA damage;rather,a sustained oxidative stress response mediates this rapid *** enhancer is present in a wide range of tumors and normal tissues,thus providing a target for cancer chemotherapy and its adverse effects on normal *** propose that SHH is a stress-responsive gene downstream of IEGs,and that traditional chemotherapy targets a specific enhancer to suppress its expression.

关键词： Sonic hedgehog Chemotherapy Immediate early genes EGR1 5-Fluorouracil

Novel Nanotrees of Crystalline Nickel Formed via Electrolytic Approach

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Nano-Micro Letters 2011年第4期3卷 264-269页

作者： Jian Wang Liying zhang Liangming Wei Chuanhai Jiang yafei zhang Key Laboratory for Thin Film and Microfabrication of the Ministry of Education Research Institute of Micro/Nano Science and TechnologySchool of Materials Science and EngineeringShanghai Jiao Tong University

Tree-shaped nickel nanocrystals with long main trunk and highly ordered branches were prepared via electrolytic method in ethylene glycol solution. The morphology and structures of nanotrees of crystalline nickel can be controlled by the processing of the surfactant(PVP) and electrolytic voltage. Magnetic property measurements at room temperature indicated that the as-prepared nanotrees of crystalline nickel possess higher saturation magnetism(MS) and coercivity(HC) than those of corresponding bulk nickel materials.

关键词： Nickel crystals Nanotrees Hysteresis loop Thermogravimetric analysis

Improving the Seismic Performance of Staircases in Building Structures with a Novel Isolator

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Computer Modeling in Engineering & Sciences 2020年第8期124卷 415-431页

作者： yafei zhang Ping Tan Haitao Ma Marco Donà Key Laboratory of Earthquake Resistance Earthquake Mitigation and Structural SafetyMinistry of EducationGuangzhou UniversityGuangzhou510405China Guangdong Provincial Key Laboratory of Earthquake Engineering and Applied Technology Guangzhou UniversityGuangzhou510405China

A staircase provides the main escape way from a building in an ***,it may suffer severe damages or even collapse during an *** improving the seismic performance of staircases,this paper proposes an innovative staircase isolator with the features of lightweight,costeffective and ease of construction and replacement,which is formed by suitable engineering plastic shims between rubber layers.A connection construction scheme is also proposed for the isolated *** performance tests have been carried out to characterize the isolator in terms of mechanic behavior and ultimate *** test results show that mechanical properties of the proposed staircase isolator are excellent and suitable for staircase in building *** order to investigate the influence of staircase on building structural responses,time history analyses of a typical building structure without staircase(WS),with fixed staircase(FS)and with isolated staircase(IS)are conducted and compared within the environment of *** show that staircase isolation can effectively eliminate the diagonal bracing effect of staircase slab and make structural components uniformly *** the novel isolator is employed for staircase in a building structure,there is no vulnerable position in staircase and the performance of staircase in building structure can be greatly enhanced.

关键词： Seismic isolation seismic performance of staircases staircase isolation engineering-plastics rubber isolator rubber isolator

Stability analysis of a slope containing water-sensitive mudstone considering different rainfall conditions at an open-pit mine

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International Journal of Coal Science & Technology 2023年第4期10卷 233-253页

作者： Guoyu Yang Yanlong Chen Xuanyu Liu Ri Yang yafei zhang Jialong zhang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou 221116China School of Mines China University of Mining and TechnologyXuzhou 221116China Harwusu Open-Pit Mine China Shenhua Energy Co.LtdOrdos 010300China China Energy Investment Beidian Shengli Energy Co. LtdXinlinhot 026000China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 221116China

Mudstone, as a typical soft rock with wide distribution, has been endangering the slopes containing mudstone by its watersensitivity of swelling and weakening strength when encountering water. To comprehensively understand the water-sensitivity of mudstone and reveal its infuence on slope stability, we took the working slope containing water-sensitive mudstone of Shengli No.1 open-pit coal mine in Xilinhot, Inner Mongolia, China, as an example. Mudstone samples taken from the working slope were remodeled and saturated, and then triaxial tested to obtain the efective cohesion and efective internal friction angle. The flter paper method was used to obtain the soil–water characteristic curve of unsaturated mudstone. The pore structure of mudstone samples with diferent water contents were analyzed using the mercury intrusion porosimetry tests combined with the fractal dimension. The total pore content of the mudstone sample with lower water content is greater than that of the mudstone sample with higher water content. The mesopores are more in the mudstone sample with lower water content, while the small pores are more in the mudstone sample with higher water content. The variation of water content will change the complexity of mudstone pore structure. The higher the water content, the simpler the mudstone pore structure and the smoother the pore surface. Numerical calculations were conducted on the stability of the working slope under diferent rainfall conditions. The efective saturation on the mudstone layer surface changed and the plastic strain all occurred on the mudstone steps under diferent rainfall conditions. The key to preventing landslide of the slope containing water-sensitive mudstone in Shengli No.1 open-pit coal mine is to control the deformation and sliding of the mudstone layer.

关键词： Water-sensitivity SWCC Pore structure Rainfall infltration Slope stability

Advances in Conceptual Electronic Nanodevices based on 0D and 1D Nanomaterials

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Nano-Micro Letters 2014年第1期6卷 1-19页

作者： yafei zhang Li Franklin Duan Yaozhong zhang Jian Wang Huijuan Geng Qing zhang Key Laboratory for Thin Film and Microfabrication Technology of the Ministry of Education Research Institute of Micro/Nano Science and TechnologyShanghai Jiao Tong University School of EEE Nanyang Technological University Nanyang Technological University

Nanoelectronic devices are being extensively developed in these years with a large variety of potential applications. In this article, some recent developments in nanoelectronic devices, including their principles, structures and potential applications are reviewed. As nanodevices work in nanometer dimensions, they consume much less power and function much faster than conventional microelectronic devices. Nanoelectronic devices can operate in different principles so that they can be further grouped into field emission devices,molecular devices, quantum devices, etc. Nanodevices can function as sensors, diodes, transistors, photovoltaic and light emitting devices, etc. Recent advances in both theoretical simulation and fabrication technologies expedite the development process from device design to prototype demonstration. Practical applications with a great market value from nanoelectronic devices are expected in near future.

关键词： Field emission nanodevices Molecular nanodevices Quantum nanodevices Semiconductor nanodevices

The Strength of Structural Diversity in Online Social Networks

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Research 2021年第1期2021卷 1203-1212页

作者： yafei zhang Lin Wang Jonathan JHZhu Xiaofan Wang Alex‘Sandy’Pentland Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information ProcessingMinistry of Education of ChinaShanghai 200240China Department of Media and Communication and School of Data Science City University of Hong KongHong Kong S.A.R.China Department of Automation Shanghai UniversityShanghai 200444China Media Lab Massachusetts Institute of TechnologyCambridgeMA 02139USA

Understanding the way individuals are interconnected in social networks is of prime significance to predict their collective *** a large-scale dataset from a knowledge-sharing website,this paper presents an exploratory investigation of the way to depict structural diversity in directed networks and how it can be utilized to predict one’s online social *** capture the structural diversity of an individual,we first consider the number of weakly and strongly connected components in one’s contact neighborhood and further take the coexposure network of social neighbors into *** show empirical evidence that the structural diversity of an individual is able to provide valuable insights to predict personal online social reputation,and the inclusion of a coexposure network provides an additional ingredient to achieve that *** synthetically controlling several possible confounding factors through matching experiments,structural diversity still plays a nonnegligible role in the prediction of personal online social *** work constitutes one of the first attempts to empirically study structural diversity in directed networks and has practical implications for a range of domains,such as social influence and collective intelligence studies.

关键词： collective networks founding