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    题名 作者 年代 出处 被引量
1Aerodynamic Design Methodology for Blended Wing Body Transport显示文摘This paper puts forward a design idea for blended wing body(BWB).The idea is described as that cruise point,maximum lift to drag point and pitch trim point are in the same flight attitude.According to this design idea,design objectives and constraints are defined.By applying low and high fidelity aerodynamic analysis tools,BWB aerodynamic design methodology is established by the combination of optimization design and inverse design methods.High lift to drag ratio,pitch trim and acceptable buffet margin can be achieved by this design methodology.For 300-passenger BWB configuration based on static stability design,as compared with initial configuration,the maximum lift to drag ratio and pitch trim are achieved at cruise condition,zero lift pitching moment is positive,and buffet characteristics is well.Fuel burn of 300-passenger BWB configuration is also significantly reduced as compared with conventional civil transports.Because aerodynamic design is carried out under the constraints of BWB design requirements,the design configuration fulfills the demands for interior layout and provides a solid foundation for continuous work.LI Peifeng ZHANG Binqian CHEN Yingchun YUAN Changsheng LIN Yu 2012Chinese Journal of Aeronautics2012,25,4:29
2Deficit Estimation and Welfare Effects after the 1994 Fiscal Reform in China:Evidence from the County Level显示文摘用中国的县的从越过所有的县级的预算的数据的简单统计分析,现在的纸检验是否财政分散影响了的 post-1994 再分配在县级。新财政系统不太能比旧的在财政不平衡缩小内部县的分散,甚至在拿以后内部政府转移支付进说明。尽管与 post-1994 系统平均在所有县花的人均的福利有谦虚增加,许多新找到的财政资源在薪金和行政开销上被花了而非在公共商品上花。因此,中国的税系统的改革被加强,是必要的。Peifeng Zhang Victor Shih 2008China & World Economy2008,16,3:7
3Review on evolution and evaluation of asphalt pavement structures and materials显示文摘The purpose of this study was to summarize the wide-range literatures on asphalt pavements, explore the evolution of road pavements, analyze typical asphalt pavement structures, highlight current trends in research and industry, and to recommend future areas of research and development. In this research, road pavement evolution was explored from the earliest roads to the modern pavements. A new method was recommended to categorize asphalt pavement materials into the three large families which may be further sub-divided according to their mechanical parameters. A unified asphalt pavement classification(UAPC) method was proposed and the worldwide asphalt pavements could be divided into six types through the new method. Based o n the UAPC method, 1087 asphalt pavement structures were classified and analyzed to explore the asphalt thickness variation. In order to evaluate asphalt pavement performance, the Chinese design specification was employed for analyzing lives of 29 high-volume pavements and 28 low-volume pavements. Through this research, it was found that:(1) in the past 100 years, asphalt pavement materials and structures had been becoming more and more strong;(2) asphalt layer thicknesses were various from 5 to 60 cm and the overall pavement thicknesses were various from 28 to 160 cm;(3) the long-life pavements in the other countries may become'shorter-life' pavements according to the prediction based on the Chinese specification.Yu Liu Peifeng Su Miaomiao Li Zhanping You Mohan Zhao 2020Journal of Traffic and Transportation Engineering(English Edition)2020,7,5:6
4Transport and deposition of nanoparticles in bend tube with circular cross-section显示文摘Transport and deposition of nanoparticles in bend tube with circular cross-section were simulated numerically for different Reynolds numbers and Dean numbers.A finite-volume code and the SIMPLE scheme were used to solve the equations.The results show that the distribution of nanoparticle concentration is symmetrical with respect to the top and bottom sides of the tube.The diameter of the nanoparticles has a weak effect on the distribution of nanoparticle concentration.The maximum and minimum of the deposition enhancement factor occur near the outside and inside walls of the bend tube,respectively.The higher the Reynolds number is,the shorter is the time for nanoparticle deposition.The bend curvature radius has a slight effect on the deposition enhancement factor.Peifeng Lin Jianzhong Lin 2009Progress in Natural Science:Materials International2009,19,1:6
5Enhanced photoresponse of Cu2O/ZnO heterojunction with piezo-modulated interface engineering显示文摘Pei Lin Xiang Chen Xiaoqin Yan Zheng Zhang Haoge Yuan Peifeng Li Yanguang Zhao Yue Zhang 2014Nano Research2014,7,6:6
6Superior adsorption performance of graphitic carbon nitride nanosheets for both cationic and anionic heavy metals from wastewater显示文摘Water pollution caused by highly toxic Cd(II), Pb(II), and Cr(VI) is a serious problem. In the present work,a green and low-cost adsorbent of g-C_3N_4 nanosheets was developed with superior capacity for both cationic and anionic heavy metals. The adsorbent was easily fabricated through one-step calcination of guanidine hydrochloride with thickness less than 1.6 nm and specific surface area of 111.2 m^2·g^(-1). Kinetic and isotherm studies suggest that the adsorption is an endothermic chemisorption process, occurring on the energetically heterogeneous surface based on a hybrid mechanism of multilayer and monolayer adsorption. The tri-s-triazine units and surface N-containing groups of g-C_3N_4 nanosheets are proposed to be responsible for the adsorption process.Further study on pH demonstrates that electrostatic interaction plays an important role. The maximum adsorption capacity of Cd(II), Pb(II), and Cr(VI) on g-C_3N_4 nanosheets is 123.205 mg·g^(-1), 136.571 mg·g^(-1),and 684.451 mg·g^(-1), respectively. The better adsorption performance of the adsorbent than that of the recently reported nanomaterials and low-cost adsorbents proves its great application potential in the removal of heavy metal contaminants from wastewater. The present paper developed a promising adsorbent which will certainly find applications in wastewater treatment and also provides guiding significance in designing adsorption processes.Gang Xiao Yaoqiang Wang Shengnan Xu Peifeng Li Chen Yang Yu Jin Qiufeng Sun Haijia Su 2019Chinese Journal of Chemical Engineering2019,27,2:5
7A new method for evaluating the drought tolerance of upland rice cultivars显示文摘Worldwide, approximately 27 million ha of rice are grown in upland rather than paddy fields, and is subject to drought stress. To counter this stress, it is desirable to breed new rice cultivars with improved drought tolerance. For breeding purposes, especially for breeding upland rice, it is desirable to develop a simple and accurate method to evaluate rice drought tolerance. We describe a new method that can be used to evaluate efficiently the drought tolerance degree(DTD) of upland rice cultivars, and call it the DTD method.DTD is defined as the mean of the ratios of green leaf length to total leaf length of the top three leaves in every rice seedling after drought treatment, and thus takes values from zero to one. To test whether the DTD method works effectively to evaluate drought tolerance of upland rice cultivars, we determined the DTD values of 13 upland rice cultivars showing varying degrees of drought tolerance in drought-tolerance trials. The idrl-1 mutant, which displayed the strongest drought tolerance of the 13 cultivars as identified by drought-tolerance trials under severe drought stress, had the highest DTD value and297-28, displaying the weakest drought tolerance, had the lowest DTD value. Further analyses of water potential, survival rate, panicles per plant, spikelets per panicle, seed setting rate, yield per plant, and contents of proline, chlorophyll, and malondialdehyde(MDA) indicated that DTD values are in general correlated with the values of these traits,making this new method useful for assessing the drought tolerance of upland rice cultivars.These results show that the DTD method is a simple, direct and relatively accurate evaluation method for drought-tolerance breeding of upland rice.Xiaofeng Zu Yanke Lu Qianqian Wang Peifeng Chu Wei Miao Huaqi Wang Honggui La 2017The Crop Journal2017,5,6:5
8Influence of Tip End-plate on Noise of Small Axial Fan显示文摘In this work, tip end-plate is used to improve the noise performance of small axial fans. Both numerical simulations and experimental methods were adopted to study the fluid flow and noise level of axial fans. Four modified models and the prototype are simulated. Influences of tip end-plate on static characteristics, internal flow field and noise of small axial fans are analyzed. The results show that on basis of the prototype, the model with the tip end-plate of 2 mm width and changed length achieved best noise performance. The overall sound pressure level of the model with the tip end-plate of 2 mm width and changed length is 2.4 dB less than that of the prototype at the monitoring point in specified far field. It is found that the mechanism of noise reduction is due to the decrease of vorticity variation on the surface of blades caused by the tip end-plate. Compared with the prototype, the static pressure of the model with the tip end-plate of 2 mm width and changed length at design flow rate decreases by 2 Pa and the efficiency decreases by 0.8%. It is concluded that the method of adding tip end-plate to impeller blades has a positive influence on reducing noise, but it may diminish the static characteristics of small axial fan to some extent.MAO Hongya WANG Yanping LIN Peifeng JIN Yingzi Toshiaki Setoguchi Heuy Dong Kim 2017Journal of Thermal Science2017,26,1:4
9Effect of Inlet Guide Vanes on the Performance of Small Axial Flow Fan显示文摘Effects of the inlet guide vanes on the static characteristics, aerodynamic noise and internal flow characteristics of a small axial flow fan are studied in this work. The inlet guide vanes with different outlet angle are designed,which are mounted on the casing and located at the upstream of the impeller of the prototype fan. Both steady and unsteady flow simulations are performed. The steady flow is simulated by the calculations of Navier-Stokes equations coupled with RNG k-epsilon turbulence model, while the unsteady flow is computed with large eddy simulation. According to the theoretical analysis, the inlet guide vanes with outlet angle of 60° are regarded as the optimal inlet guide vanes. The static characteristic experiment is carried out in a standard test rig and the aerodynamic noise is tested in a semi-anechoic room. Then, performances of the fan with optimal inlet guide vanes are compared with those of the prototype fan. The results show that there is reasonable agreement between the simulation results and the experimental data. It is found that the static characteristics of small axial flow fan is improved obviously after installing the optimal inlet guide vanes. Meanwhile, the optimal inlet guide vanes have effect on reducing noise at the near field, but have little effect on the noise at the far field.LIU Yang LIN Zhe LIN Peifeng JIN Yingzi Toshiaki Setoguchi Heuy Dong Kim 2017Journal of Thermal Science2017,26,6:4
107,8-Dihydroxyflavone suppresses proliferation and induces apoptosis of human osteosarcoma cells显示文摘Recent studies suggest that 7,8-dihydroxyflavone(7,8-DHF)inhibits the development of several tumors.However,its role in osteosarcoma(OS)remains unknown.This study was designed to investigate the effects and underlying mechanisms of 7,8-DHF that may influence OS development.Human OS cell lines(U2OS and 143B)were treated with 7,8-DHF;cell viability and cell migration were assessed by methylthiazolyldiphenyl-tetrazolium bromide(MTT)assay and wound-healing assay,respectively;and cell death and apoptosis were evaluated by LIVE/DEAD staining and terminal deoxynucleotidyl transferase(TdT)dUTP nick-end labeling(TUNEL)assay,respectively.Reactive oxygen species production was measured using 2,7-dichlorodihydrofluorescein diacetate probe.Akt,Bcl-xL/Bcl-2 asociated death promoter(Bad),p38 mitogen-activated protein kinase(MAPK),extracellular regulated protein kinase(ERK),and c-Jun N-terminal kinase(JNK)expression and their respective phosphorylation levels were detected by western blot analysis.We found that 7,8-DHF reduced cell viability in a dose-dependent manner and also promoted apoptosis,inhibited migration,and induced oxidative stress in OS cells.Moreover,7,8-DHF inhibited Akt,Bad,and p38MAPK,but activated ERK and JNK signals.In summary,our results suggest that 7,8-DHF inhibits OS progression,possibly by regulating Akt/Bad and MAPK signaling.These findings provide new evidence for the pharmacological effects of 7,8-DHF that may improve drug therapy for OS patients.Jing Zhao Peifeng Li Hua Zhu Fengqin Ge Jie Liu Jingjun Xia Pengzhou Hang 2021Acta Biochimica et Biophysica Sinica2021,53,7:3
11路面蜃景:热空气的把戏?显示文摘路面'下蜃景'是日常生活中极易见到的现象.长期以来,它被学术界公认为是由于路面空气层温度梯度引起的折射率梯度所形成的一种光的折射现象.但也有一种不同的观点,认为蜃景就是在掠入射条件下的一种镜反射现象.由于缺少合理、定量的证据,公认的光折射理论并没有受到动摇.本文展示了几幅从湖北省武汉市喻家山北路的一段路面上实验拍摄到的蜃景图像,拍摄时间为2009年12月的冬日.同时,采用热电偶测量结果表明,该路表面及其上空气层并无明显的温度梯度.这个实验为质疑'下蜃景'由温度梯度引起光线折射而形成的理论提供了直接证据.此外,检测发现,发生蜃景反射的道路平面上的临界掠入射角约0.2°,根据瑞利准则,这个角度不能使粗糙面像光滑表面一样将入射光反射.所以,该现象应作为粗糙面散射的一个似镜反射观测效果,并不能从根本上由光在空气层中发生折射来解释.本研究结果表明,这里展示的成像机制和基于观测的分析方法,为认识在粗糙面的掠入射条件下发生的多种散射现象提供了一种有潜力的方法,如在结冰湖面上偶然观测到的亮度异常的'上蜃景'以及非镜向反射峰值现象.周怀春 黄志锋 程强 吕伟 邱奎 陈辰 HSU PeiFeng 2011科学通报2011,56,4:3
12CRISPR/Cas systems for the detection of nucleic acid and nonnucleic acid targets显示文摘Clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated(Cas)systems are becoming powerful tools for disease biomarkers detection.Due to the specific recognition,cis-cleavage and nonspecific trans-cleavage capabilities,CRISPR/Cas systems have implemented the detection of nucleic acid targets(DNA and RNA)as well as non-nucleic acid targets(e.g.,proteins,exosomes,cells,and small molecules).In this review,we first summarize the principles and characteristics of various CRISPR/Cas systems,including CRISPR/Cas9,Cas12,Cas13 and Cas14 systems.Then,various types of applications of CRISPR/Cas systems used in detecting nucleic and non-nucleic acid targets are introduced emphatically.Finally,the prospects and challenges of their applications in biosensing are discussed.Weiran Su Junru Li Chen Ji Congshuo Chen Yuzheng Wang Huili Dai Fengqin Li Peifeng Liu 2023Nano Research2023,16,7:3
13Gigabit ethernet switches using a shared buffer architecture显示文摘Lau M V Shieh S Wang Peifeng 2003IEEE Communications Magazine2003,41,:2
14Effect of the Uneven Circumferential Blade Space on the Performance of Small Axial Flow Fan显示文摘Effects of the uneven circumferential blade space on static characteristics and aerodynamic noise of a small axial flow fan are studied in this work.The blade angle modulation is adopted to design a series of unequally spaced fans,which have different maximum of modulation angular displacement.The steady flow is simulated by the calculations of Navier-Stokes equations coupled with RNG k-epsilon turbulence model,while the unsteady flow is computed with large eddy simulation.According to theoretical analysis,a fan with a maximum of modulation angular displacement of 6° is regarded as the optimal unequally spaced fan.The experiment of static characteristic is carried out in a standard wind tunnel and the aerodynamic noise of both fans is tested in a semi-anechoic room.Then,performances of the optimal unequally spaced fan are compared with those of the prototype fan.The results show that there is reasonable agreement between the simulation results and the experimental data.It is found that the discrete noise of the optimal unequally spaced fan is lower than that of the prototype fan at the near field monitoring point.This can be explained that the total pressure fluctuation of the optimal unequally spaced fan is much more regular than that of the prototype fan.LIU Yang LIN Zhe LIN Peifeng JIN Yingzi Toshiaki Setoguchi Heuy Dong Kim 2016Journal of Thermal Science2016,25,6:2
15Spectroscopic identification towards tunable mesoscale aggregates of zinc tetraphenylporphyrin for materials显示文摘We present a study of spectroscopic identification towards the molecular aggregates of zinc tetraphenylporphyrin(ZnTPP) illustrating how the energy states and intermolecular interactions determine the tunable properties of functional materials in condensation processes. Distinguishable fingerprints of ZnTPP nanorods and nanosheets are addressed utilizing X-ray diffraction(XRD), Raman and UV-vis absorption spectroscopies. Although these ZnTPPs are assigned to J-aggregation at different extent, the spectral analysis reveals a significant role of the intermolecular interactions associated with varying mesoscale architectures. Energy decomposition analysis(EDA) revealed that the varied ZnTPP aggregates are stabilized by altered dispersion interactions due to the dominant π…π stacking between the monomers.Pan An Longtian Kang Zhen Tang Peifeng Su Zhixun Luo 2018Chinese Chemical Letters2018,29,3:2
16Nanoparticle distribution in a rotating curved pipe considering coagulation and dispersion显示文摘We study the evolution of the particle number concentration, mass concentration, particle polydispersity, particle diameter and geometric standard deviation considering particle coagulation and dispersion in a rotating curved pipe at different Reynolds number, Schmidt number and F number. It is found that, when the Coriolis force and the centrifugal force point to the same direction, particles concentrate near the outside edge of the pipe, which becomes more obvious as time goes by. The particle number and mass concentration increase faster at the early stage than that at the later stage, and approach a stable value finally. As the coagulation proceeds, the particle diameter, polydispersity and geometric standard deviation increase and have high values in the region close to the outside edge of the pipe. When the Coriolis force and the centrifugal force point to the oppo- site direction and the Coriolis force is more dominant than the centrifugal force, particles concentrate near the inside edge of the pipe. The particles in the region with a high number concentration have high mass concentration, large diameter and high polydispersity as well as large geometric standard deviation. The particle distribution is dependent on the balance of the pipe curvature and rotating speed. The Reynolds number and the Schmidt number have effects on the particle distribution when other parameters remain unchanged. An increase in the Reynolds number leads to an increase in particle number concentration and mass concentration, and a decrease in particle polydispersity, particle diameter and geometric standard deviation. With the increase of Schmidt number the particle number concentration and mass concentration increase, and the particle polydispersity, particle diameter and geometric standard deviation decrease.LIN JianZhong LIN PeiFeng CHEN HuaJun 2011Science China(Physics,Mechanics & Astronomy)2011,54,8:2
17Performance measurement of adaptive optics system based on Strehl ratio显示文摘In this article, a method for measuring the performance of adaptive optics(AO) systems is designed and validated by experiments. The Strehl ratio(SR) which is based on the target images is used to evaluate the performance quantitatively because it relates to the effect of AO correction directly. In the calculation of the SR, to avoid energy scaling in the diffraction-limited point spread function, an algorithm based on the integral of the optical transfer function(OTF) is proposed. Then, a 97-element AO system is established to validate this method, and a white-light fiber source is used as a point-like target. To simulate the practical conditions which influence the performance of the AO system, targets of different brightness are simulated in terms of different signal-to-noise ratios(SNRs) of the Shack-Hartmann(SH), and atmospheric turbulence is simulated in terms of the Fried's coherence length and the Greenwood's frequency. Finally, two experiments are conducted in which the SR of different simulated conditions are measured. The results of the experiments show that for a moderate SNR of SH the experimenting AO system is capable of closed-loop wavefront correction when the Fried's coherence length is larger than 5cm and the Greenwood's frequency is lower than 60 Hz. The results also show that the performance of AO is susceptible to the SNR of SH. The experiments validates the effectiveness of this method.Wang Liang Chen Tao Lin Xudong Wei Peifeng Liu Xinyue Jia Jianlu 2016The Journal of China Universities of Posts and Telecommunications2016,23,3:2
18Simulation and Experiment Research of Aerodynamic Performance of Small Axial Fans with Struts显示文摘Interaction between rotor and struts has great effect on the performance of small axial fan systems.The small axial fan systems are selected as the studied objects in this paper,and four square struts are downstream of the rotor.The cross section of the struts is changed to the cylindrical shapes for the investigation:one is in the same hydraulic diameter as the square struts and another one is in the same cross section as the square struts.Influence of the shape of the struts on the static pressure characteristics,the internal flow and the sound emission of the small axial fans are studied.Standard K-ε turbulence model and SIMPLE algorithm are applied in the calculation of the steady fluid field,and the curves of the pressure rising against the flow rate are obtained,which demonstrates that the simulation results are in nice consistence with the experimental data.The steady calculation results are set as the initial field in the unsteady calculation.Large eddy simulation and PISO algorithm are used in the transient calculation,and the Ffowcs Williams-Hawkings model is introduced to predict the sound level at the eight monitoring points.The research results show that:the static pressure coefficients of the fan with cylindrical struts increase by about 25%compared to the fan with square struts,and the efficiencies increase by about 28.6%.The research provides a theoretical guide for shape optimization and noise reduction of small axial fan with struts.CHU Wei LIN Peifeng ZHANG Li JIN Yingzi WANG Yanping Heuy Dong Kim Toshiaki Setoguchi 2016Journal of Thermal Science2016,25,3:2
19Electromagnetic-thermal-structure multi-layer nonlinear elastoplastic modelling study on epoxy-impregnated REBCO pancake coils in high-field magnets显示文摘The elastoplastic mechanical behaviour of an epoxy-impregnated REBCO pancake winding under cryogenics and high magnetic field is investigated in the frame of finite element(FE)modelling.A two-dimensional axisymmetric electromagnetic-thermal-structure multi-physics multi-layer FE model with main layers of the coated conductor and insulation materials is developed.The radial stress and hoop stress on each constituent layer induced by thermal mismatch stress during cooling are investigated.The mechanical behaviour of each constituent material is also analysed by considering the thermal mismatch stress and electromagnetic force under 20 T background field.The results show that discrete stresses appear in all the constituent materials indicating that the multi-layer winding model containing the main constituent materials is necessary for the accurate stress analysis in an epoxy-impregnated REBCO winding.The stress of each constituent material induced by thermal mismatch during cooling process are too high to be ignored in the subsequent electromagnetic structure analysis.The mechanical-magnetic coupling analyses show that the stresses of all the constituent materials increase with the transport current.The plastic failure mainly induced by hoop stress successively occurs on copper stabilizer and Hastelloy substrate of the innermost turn,and the plastic region propagates from the inner turns to the outer turns with the increase of transport current.The failure of the superconducting layer occurs before the yield in Hastelloy due to the direct action of Lorentz force on the superconducting layers.The transverse tensile stress increases with the increasing transport current,indicating that the risk of transverse delamination failure increases with the increase of transport current.The mechanical failure modes including delamination within the conductor,plastic deformation in substrate and crack in superconducting layer should be seriously considered.Peifeng Gao Mingzhi Guan Xingzhe Wang Youhe Zhou 2022Superconductivity2022,,1:2
20Effects of taurocholic acid on immunoregulation in mice显示文摘Caiyun Wang Lei Li Hong Guan Saiyinna Tong Mingqiang Liu Chang Liu Ziying Zhang Chenguang Du Peifeng Li 2012International Immunopharmacology2012,,:2
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