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Acta Mechanica Sinica 2011年第5期27卷 833-839页

作者： fan Zhan Yu-Bo fan Xiao-Yan deng Key Laboratory for Biomechanics and Mechanobiologyof Ministry of Education School of Biological Science and Medical EngineeringBeihang University 100191 Beijing China

Platelet concentration near the blood vessel wall is one of the major factors in the adhesion of platelets to the *** our previous studies,it was found that swirling flows could suppress platelet adhesion in small-caliber artificial grafts and end-to-end *** order to better understand the beneficial effect of the swirling flow,we numerically analyzed the near-wall concentration distribution of platelets in a straight tube and a sudden tubular expansion tube under both swirling flow and normal flow *** numerical models were created based on our previous experimental *** simulation results revealed that when compared with the normal flow,the swirling flow could significantly reduce the near-wall concentration of platelets in both the straight tube and the expansion *** present numerical study therefore indicates that the reduction in platelet adhesion under swirling flow conditions in small-caliber arterial grafts,or in end-to-end anastomoses as observed in our previous experimental study,was possibly through a mechanism of platelet transport,in which the swirling flow reduced the near-wall concentration of platelets.

关键词： Platelet near-wall concentration · Swirling flow · Small-caliber arterial grafts · End-to-end anastomosis

Numerical exploration on jet oscillation mechanism of counterflowing jet ahead of a hypersonic lifting-body vehicle

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Science China(Technological Sciences) 2018年第7期61卷 1056-1071页

作者： deng fan XIE Feng HUANG Wei DONG Hao ZHANG Dong Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle TechnologyBeijing 100076China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Science and Technology on Scramjet Laboratory National University of Defense TechnologyChangsha 410073China College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China National Key Laboratory of Aerospace Flight Dynamics Northwestern Polytechnical UniversityXi'an 710072China

Numerical investigation of a supersonic jet from the nose of a lifting-body vehicle opposing a hypersonic flow with the freestream Mach number being 8.0 at 40 km altitude was carried out by solving the three-dimensional, time-accurate Navier-Stokes equations with a hybrid meshes approach. Based on the analysis of the flow field structures and aerodynamic characteristics, the behaviours relevant to the LPM jet were discussed in detail, including the drag reduction effect, the periodic oscillation and the feedback loop. The obtained results show that the flow oscillation characteristic of the LPM jet is low-frequency and high-amplitude while that of the SPM jet is high-frequency and low-amplitude. Compared with the clearly dominant frequencies of the LPM jet, the SPM jet exhibits a broad-band structure. The LPM jet can sustain drag reduction effect until the angle of attack is 8°, and the lift-to-drag ratio of the vehicle is effectively improved by 6.95% at angle of attack of 6°. The self-sustained oscillation process was studied by a typical oscillating cycle of the drag force coefficient and the variation of the instantaneous pressure distribution,which reveals an off-axial flapping motion of the conical shear layer. The variation of the subsonic recirculation zone ahead of the vehicle nose strengthens the understanding of the jet behavior including the source of instability in the long penetration mode and the mechanism of the feedback loop. The aim of this paper is to advance the technology readiness level for the counterflowing jet applied as an active control technology in hypersonic flows by gaining a better insight of the flow physics.

关键词： hypersonic lifting-body vehicle counterflowing jet LPM periodic oscillation

Integration of cryogenic trap to gas chromatography-sulfur chemiluminescent detection for online analysis of hydrogen gas for volatile sulfur compounds

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Chinese Chemical Letters 2021年第11期32卷 3440-3445页

作者： Yi Pan fan-Feng deng Zheng fang Han-Jiao Chen Zhou Long Xian-deng Hou Analytical Testing Center Sichuan UniversityChengdu 610064China Institute of Chemistry National Institute of Measurement and Testing TechnologyChengdu 610021China

Hydrogen fuel cells are among the promising energy sources worldwide,which could accomplish cyclic production of energy and avoid the emission of green-house or contaminative ***,sulfur compounds(SCs)even at trace level(nmol/mol)are usually involved in cell construction and further H_(2)production,which would cause degradation of the catalysts and shorten the lifetime of the fuel ***,the highly reactive SCs could cause varied species and concentrations of them in complex matrices,so online rather than offline analysis of SCs in H_(2)would be *** this context,we developed a new system combining online cryogenic preconcentration of nine SCs and subsequent determination by GC-SCD(sulfur chemiluminescent detector),with the correlation coefficients of the calibration curves higher than 0.999,calculated limits of detection no higher than 0.050 nmol/mol,analytical time around 30 min per sample,and satisfactory precision and accuracy(RSD<5%and SD<15%).The analytical performance was much better than or at least comparable to the previously reported and the developed system was successfully applied for real sample analysis.

关键词： Gas-chromatography Hydrogen fuel cell Online cryogenic trap Sulfur chemiluminescent detector Volatile sulfur compounds

Drag Reduction Effect for Hypersonic Lifting-Body Vehicle with Counterflowing Jet

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第5期35卷 789-799页

作者： Dong Hao deng fan Xie Feng Geng Xi Cheng Keming College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics General Control Department Space Transportation Technology CO.Ltd. Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center

This study takes the novel approach of using a counterflowing jet positioned on the nose of a lifting-body vehicle to explore its drag reduction effect at a range of angles of *** studies are conducted at a freestream Mach number of 8 in standard atmospheric conditions corresponding to the altitude of 40 *** effects of jet pressure ratio and flying angles of attack on drag reduction of the model are systematically *** the reverse thrust generated from the counterflowing jet,the drag on the nose at hypersonic speeds could be reduced up to 66%.The maximum lift-to-drag ratio of the model is obtained at 6°;meanwhile,the counterflowing jet produces a drag reduction of 8.8%for the whole *** addition to the nose,the counterflowing jet influences the drag by increasing the pressure drag of the model and reducing the skin friction drag of the first cone within 8°.The results show that the potential of the counterflowing jet as a means of active flow control for drag reduction is significant in the engineering application on hypersonic lifting-body vehicles.

关键词： hypersonic lifting-body counterflowing jet drag numerical simulation

Two New Piperazine Templated Lanthanide Sulfates with 2D Corrugated Layered Crystal Structures

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Chemical Research in Chinese Universities 2013年第1期29卷 10-14页

作者： ZHANG deng fan Xin-rong LU Yun XU Yan State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical Engineering Nanjing University of Technology Nanjing 210009 P. R. China

Two new piperazine templated lanthanide sulfates （C4N2HI2）1.5[Ln（SO4）3（H20）]H20[Ln=Gd（1）, Tb（2）] have been synthesized solvothermally and structurally characterized by single crystal X-ray diffraction（XRD）, infrared（IR） spectroscopy, thermal analysis, fluorescent spectra and inductively coupled plasma（ICP）. Single crystal X-ray diffraction reveals that both compounds 1 and 2 crystallized in the monoclinic crystal system, with space group P2t/c and cell dimensions： a=0.64468（19） nm, b=2.9979（9） nm, c=0.9818（3） nm, fl=101.271（4）, V=l.8608（10） nm3, Z=4 for compound 1; a=0.64259（19） nm, b=3.0010（9） rim, c=0.9812（3） nm, fl=101.229（4）, V=1.8560（10） nm3, Z=4 for compound 2. Compounds 1 and 2 are isomorphous and have similar 2D corrugated inorganic frameworks fabricated via the connection of single chains and $204 groups, while fully protonated piperazine cations and water molecules are located between the inorganic layers. The solid state luminescent properties of compound 2 were investigated and it displayed a typical luminescent property of Tb3＋ with excitation wavelength at 371 nm.

关键词： Solvothermal synthesis Lanthanide sulfate Layered structure Luminescence

Intrathecal liproxstatin-1 delivery inhibits ferroptosis and attenuates mechanical and thermal hypersensitivities in rats with complete Freund's adjuvant-induced inflammatory pain

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Neural Regeneration Research 2023年第2期18卷 456-462页

作者： Yi-fan deng Ping Xiang Jing-Yi Du Jian-Fen Liang Xiang Li Department of Anesthesiology The Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Department of Medical Quality Management Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

Previous studies have confirmed the relationship between iron-dependent ferroptosis and a peripheral nerve injury-induced neuropathic pain ***,the role of fe rroptosis in inflammatory pain remains ***,we aimed to explore whether ferroptosis in the spinal cord and do rsal root ganglion contributes to complete Freund's adjuvant(CFA)-induced painful behaviors in *** results revealed that various biochemical and morphological changes were associated with ferroptosis in the spinal cord and dorsal root ganglion tissues of CFA *** changes included iron overload,enhanced lipid peroxidation,disorders of anti-acyl-coenzyme A synthetase long-chain family member 4 and glutathione peroxidase 4 levels,and abnormal morphological changes in *** treatment of liproxstatin-1(a ferroptosis inhibitor)reve rsed these ferroptosis-related changes and alleviated mechanical and thermal hype rsensitivities in CFA *** study demonstrated the occurrence of fe rroptosis in the spinal cord and do rsal root ganglion tissues in a rodent model of inflammatory pain and indicated that intrathecal administration of fe rroptosis inhibitors,such as liproxstatin-1,is a potential therapeutic strategy for treating inflammatory pain.

关键词： cell death complete Freund's adjuvant dorsal root ganglion ferroptosis inflammatory pain intrathecal delivery liproxstatin-1 spinal cord

Quantitative analysis of the content of nitrogen and sulfur in coal based on laserinduced breakdown spectroscopy: effects of variable selection

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Plasma Science and Technology 2020年第7期22卷 36-43页

作者： fan deng Yu DING Yujuan CHEN Shaonong ZHU Feifan CHEN Jiangsu Key Laboratory of Big Data Analysis Technology Nanjing University of Information Science&TechnologyNanjing 210044People's Republic of China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science&TechnologyNanjing 210044People's Republic of China Jiangsu Engineering Research Center on Meteorological Energy Using and Control Nanjing University of Information Science&TechnologyNanjing 210044People's Republic of China

Coal is a crucial fossil energy in today’s society,and the detection of sulfir(S) and nitrogen(N)in coal is essential for the evaluation of coal ***,an efficient method is needed to quantitatively analyze N and S content in coal,to achieve the purpose of clean utilization of *** study applied laser-induced breakdown spectroscopy(LIBS) to test coal quality,and combined two variable selection algorithms,competitive adaptive reweighted sampling(CARS) and the successive projections algorithm(SPA),to establish the corresponding partial least square(PLS) *** results of the experiment were as *** PLS modeled with the full spectrum of 27,620 variables has poor accuracy,the coefficient of determination of the test set(R^2 P) and root mean square error of the test set(RMSEP) of nitrogen were 0.5172 and 0.2263,respectively,and those of sulfur were0.5784 and 0.5811,*** CARS-PLS screened 37 and 25 variables respectively in the detection of N and S elements,but the prediction ability of the model did not improve ***-PLS finally screened 14 and 11 variables respectively through successive projections,and obtained the best prediction effect among the three *** R^2 P and RMSEP of nitrogen were0.9873 and 0.0208,respectively,and those of sulfur were 0.9451 and 0.2082,*** general,the predictive results of the two elements increased by about 90% for RMSEP and 60% for R2 P compared with *** results show that LIBS combined with SPA-PLS has good potential for detecting N and S content in coal,and is a very promising technology for industrial application.

关键词： variable selection LIBS coal CARS and SPA

Model and experiment-based evaluation of seawater-based urine phosphorus recovery(SUPR)process

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Frontiers of Environmental Science & Engineering 2024年第11期18卷 133-144页

作者： Wen-Tao Tang Yihang Xiao Yang-fan deng Yunkai TAN Guang-Hao Chen Tianwei HAO Zhuhai UM Science&Technology Research Institute Zhuhai 519031China Department of Civil and Environmental Engineering The Hong Kong University of Science&TechnologyHong Kong 999077China Department of Civil and Environmental Engineering Faculty of Science and TechnologyUniversity of MacaoMacao 999078China

Leveraging seawater toilet flushing system in Hong Kong,China,a Seawater-based Urine Phosphorus Recovery(SUPR)process that integrates ureolysis and phosphorus(P)recovery was proposed in our earlier *** this study,a thermodynamic model was applied to evaluate the effects of ureolysis and the seawater-to-urine mixing ratio(S/U ratio)on P precipitation in the SUPR *** results suggested that effective P recovery was thermodynamically feasible across a wide range of S/U ratios,with elevated pH levels resulting from ureolysis being critical for P ***,a SUPR reactor was developed to validate this *** the hydraulic retention time(HRT)exceeded 3 h and the S/U ratio was lower than 3:1,more than 98%of P could be recovered without urine storage,chemical dosage,or external *** decrease in the HRT and increase in S/U ratio caused flushing out of fine precipitates,resulting in a relatively low P recovery ***,this could be advantageous when downstream urine nitrification is implemented,as dilution of urine can alleviate the inhibitory effects of free ammonia and free nitrous acid,as well as overcome the P limitation problem,thus facilitating urine ***,there is a trade-off between optimizing P recovery and nitrification efficiencies.

关键词： Phosphorus recovery Struvite Urine nitrification Source separation Seawater toilet flushing

Changes in the Urban Surface Thermal Environment of a Chinese Coastal City Revealed by Downscaling MODIS LST with Random Forest Algorithm

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Journal of Meteorological Research 2021年第5期35卷 759-774页

作者： Nuo XU fan deng Bingqi LIU Caixia LI Hancong FU Huan YANG Jiahua ZHANG School of Geosciences Yangtze UniversityWuhan 430100 Nanhu Laboratory Jiaxing 3140023 Beijing Big Data Advanced Technology Institute Beijing 100871 University of Chinese Academy of Sciences Beijing 100049 Key Laboratory of Digital Earth Sciences Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094

Analysis of the formation and evolution of urban surface thermal environment is crucial for urban planning and improving the environment of a *** was selected in this study as a typical coastal city undergoing rapid urbanization,and the spatiotemporal dynamic characteristics of its urban surface thermal environment from2010 to 2019 were *** random forest(RF)algorithm was adopted to obtain its land surface temperature(LST)map with 30-m resolution by downscaling the Moderate Resolution Imaging Spectroradiometer(MODIS)LST product;the remote sensing indices emphasizing different land cover types,LST calculated by the radiative transfer equation,and elevation were used as input variables in the *** heat island intensity(HII),urban heat island(UHI)volume,and UHI grade were used to analyze the spatiotemporal dynamic characteristics of the urban surface thermal environment in *** results show an increasing trend in average HII between 1.1 and 2.52°C in the study area over the past 10 *** northern city appeared to have the highest UHI volume,while change of the UHI volume in Huangdao District of southwestern Qingdao was the most *** areas with high HII have gradually expanded during the last 10 years,and the areas with a 10-yr persistently high HII are distributed mainly in old urban areas with high building density and a dense *** factors may influence UHI,such as artificial heat sources,surface heat sources,and hybrid heat ***,adjusting the urban structure,increasing the vegetated area,and changing building colors are proposed to mitigate UHI in the areas with continuously high HII.

关键词： surface thermal environment urban heat island downscaling random forest coastal city

Land subsidence monitoring by D-InSAR technique

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Mining Science and Technology 2011年第6期21卷 869-872页

作者： fan Hongdong deng Kazhong Ju Chengyu Zhu Chuanguang Xue Jiqun China University of Mining ＆ Technology Key Laboratory for Land Environment and Disaster Monitoring of SBSM Xuzhou 221116 China

Nowadays, the researches of using Differential Interferometric Synthetic Aperture Radar (D-InSAR) tech- nique to monitor the land subsidence are mainly on how to qualitatively analyze the subsidence areas and values, but the analysis of subsidence process and mechanism are insufficient. In order to resolve these problems, 6 scenes of ERS1/2 images captured during 1995 and 2000 in a certain place of Jiangsu province were selected to obtain the subsidence and velocities in three time segments by ''two-pass'' D- InSAR method. Then the relationships among distributions of pumping wells, exploitation quantity of groundwater, and confined water levels were studied and the subsidence mechanism was systematically analyzed. The results show that using D-InSAR technique to monitor the deformation of large area can obtain high accuracies, the disadvantages of classical observation methods can be remedied and there is a linear relationship among the velocities of land subsidence, the water level and the exploitation quantity.

关键词： InSAR "Two-pass" differential Land subsidence Confined water level Groundwater