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| 1 | Review of zero-net-mass-flux jet and its application in separation flow control显示文摘Since the zero-net-mass-flux (ZNMF) jet was first used as a laboratory flow control method in 1990's, it has attracted much attention. The ZNMF jet has unique features such as compact actuator, no requirement for external air supply, complex piping, etc., and becomes a hot topic research subject in fluid mechanics. This review introduces the state of the art in the development of ZNMF jet in the quiescent fluid, the interaction of the ZNMF jet with the cross flow and its application in the separation flow control. The evolution of the vortex ring/pair and the spacial flow structure of the ZNMF in quicent fluid or cross flow are presented, as well as the key parameter effects. At last, the applications of ZNMF jet in the wake control of the circular cylinder, the separation control on the airfoil and the aerodynamic force or moment control on MAV/UAV are presented. | ZHANG PanFeng WANG JinJun FENG LiHao | 2008 | Science China(Technological Sciences)2008，51，9： | 30 |
| 2 | Application of ^(137)Cs fingerprinting technique to interpreting sediment production records from reservoir deposits in a small catchment of the Hilly Loess Plateau,China显示文摘According to variations of 137Cs and clay contents, 44 flood couplets were identified in a profile of res- ervoir deposit with a vertical length of 28.12 m in the Yuntaishan Gully. Couplet 27 at the middle of the profile had the highest average 137Cs content of 12.65 Bq·kg?1, which indicated the 1963s' deposits, then 137Cs content decreased both downward and upward in the profile. The second top and bottom couplets had average 137Cs contents of 2.15 Bq·kg?1 and 0.92 Bq·kg?1, respectively. By integrated analysis of reservoir construction and management history, variations of 137Cs contents over the profile, sediment yields of flood couplets and rainfall data during the period of 1958-1970, individual storms related to the flood couplets were identified. 44 floods with a total sediment yield of 2.36×104 m3 occurred and flood events in a year varied between 1 and 10 times during the period of 1960-1970. 7-10 flood events occurred during the wet period of 1961-1964 with very wet autumn, while only 1-2 events during the dry period of 1965-1969. Average annual specific sediment yield was 1.29×104 t·km?2·a?1 for the Yuntaishan Gully during the period of 1960-1970, which was slightly higher than 1.11 ×104 t·km?2·a?1 for the Upper Yanhe River Basin above the Ganguyi Hydrological Station and slightly lower than 1.40 ×104 t·km?2·a?1 for the nearby Zhifang Gully during the same period. Annual specific sediment yields for the Yuntaishan Gully were correlated to the wet season's rainfalls well. | ZHANG XinBao WEN ZhongMing FENG MingYi YANG QinKe ZHENG JinJun | 2007 | Science China Earth Sciences2007，50，2： | 13 |
| 3 | Experimental investigations on separation control and flow structure around a circular cylinder with synthetic jet显示文摘Circular cylinder separation control and flow structure influenced by the synthetic jet have been experimentally investigated in a water channel. The synthetic jet is- sues from a slot and ejects toward upstream from the front stagnation point of the cylinder. It has been found that, similar to the traditional synthetic jet which is po- sitioned near the separation point or inside the separation region, the present synthetic jet arrangement constitutes an efficient way to control flow separation of the circular cylinder, but with a different control mechanism. The present synthetic jet leads to an upstream displacement of the front stagnation point and the forma- tion of a vortex pair near both sides of the exit orifice. When ReU based on the synthetic jet average exit orifice velocity is about lower than 43, a closed envelope forms in front of the windward side of the cylinder during the blowing cycle of syn- thetic jet, which acts as an apparent modification for the cylinder configuration. When ReU is high enough, an open envelope forms upstream of the cylinder, and the flow around the cylinder becomes much energetic. Thus, regardless of ReU, the present synthetic jet can improve separation for flow around a circular cylinder. With regard to the leeward side, as ReU increases, the flow separation region be- hind the cylinder gradually disappears. The flow over cylinder may be fully attached when the open envelope forms upstream of the cylinder and ReU is greater than 344. Then, the flow past the cylinder will converge near the back stagnation point of the cylinder, where a new vortex pair shedding periodically is generated due to the high shear layer. | WANG JinJun FENG LiHao XU ChaoJun | 2007 | Science China(Technological Sciences)2007，50，5： | 9 |
| 4 | Prophylactic vertebroplasty procedure applied with a resorbable bone cement can decrease the fracture risk of sandwich vertebrae:long-term evaluation of clinical outcomes显示文摘A sandwich vertebra is formed after multiple osteoporotic vertebral fractures treated by percutaneous vertebroplasty,which has a risk of developing new fractures.The purpose of our study was to(i)investigate the occurrence of new fractures in sandwich vertebra after cement augmentation procedures and to(ii)evaluate the clinical outcomes after prophylactic vertebral reinforcement applied with resorbable bone cement.From June 2011 to 2014,we analysed 55 patients with at least one sandwich vertebrae and treated with percutaneous vertebroplasty.Eighteen patients were treated by prophylactic vertebroplasty with a resorbable bone cement to strengthen the sandwich vertebrae as the prevention group.The others were the non-prevention group.All patients were examined by spinal radiographs within 1 day,6 months,12 months,24 months and thereafter.The incidence of sandwich vertebra is 8.25%(55/667)in our study.Most sandwich vertebrae(69.01%,49/71)are distributed in the thoracic-lumbar junction.There are 24 sandwich vertebrae(18 patients)and 47 sandwich vertebrae(37 patients)in either prevention group or non-prevention group,respectively.No significant difference is found between age,sex,body mass index,bone mineral density,cement disk leakage,sandwich vertebrae distribution or Cobb angle in the two groups.In the follow-up,8 out of 37(21.6%)patients(with eight sandwich vertebrae)developed new fractures in non-prevention’group,whereas no new fractures were detected in the prevention group.Neither Cobb angle nor vertebral compression rate showed significant change in the prevention group during the follow-up.However,in the non-prevention group,we found that Cobb angle increased and vertebral height lost significantly(P<0.05).Prophylactic vertebroplasty procedure applied with resorbable bone cement could decrease the rate of new fractures of sandwich vertebrae. | Pu Jia Hai Tang Hao Chen Li Bao Fei Feng He Yang Jinjun Li | 2017 | Regenerative Biomaterials2017，4，1： | 8 |
| 5 | Fourier mode decomposition of PIV data.显示文摘The modal decomposition technique is one of the most effective methods for studying the flow dynamics in a complex flow. By rejuvenating the discrete Fourier transform(DFT), this paper proposes a Fourier mode decomposition(FMD) method for the time series of particle image velocimetry(PIV) data from the fluid field. An experimental case concerning the control of the flow around a circular cylinder by a synthetic jet positioned at the rear stagnation point is used to demonstrate the use of the FMD method. In the three different regimes where the natural shedding frequency and actuation frequency dominate respectively or simultaneously, it is found that the FMD method is capable of extracting the dynamic mode along with its amplitude and phase according to the selected characteristic frequency based on the global power spectrum. For the quasiperiodic flow phenomena presented in this particular case, the FMD method can reconstruct the original flow field using the zero-th mode and the selected mode corresponding to the characteristic frequency. Similarities and differences between the FMD method and the dynamical mode decomposition(DMD) and proper orthogonal decomposition(POD) methods are also discussed. | MA LiQun FENG LiHao PAN Chong GAO Qi WANG JinJun | 2015 | Science China(Technological Sciences)2015，58，11： | 6 |
| 6 | Photooxidation of arsenic(Ⅲ) to arsenic(Ⅴ) on the surface of kaolinite clay显示文摘As one of the most toxic heavy metals, the oxidation of inorganic arsenic has drawn great attention among environmental scientists. However, little has been reported on the solar photochemical behavior of arsenic species on top-soil. In the present work, the influencing factors(p H, relative humidity(RH), humic acid(HA), trisodium citrate, and additional iron ions) and the contributions of reactive oxygen species(ROS, mainly HOUand HO2U/O2U-) to photooxidation of As(Ⅲ) to As(Ⅴ) on kaolinite surfaces under UV irradiation(λ = 365 nm)were investigated. Results showed that lower p H facilitated photooxidation, and the photooxidation efficiency increased with the increase of RH and trisodium citrate.Promotion or inhibition of As(Ⅲ) photooxidation by HA was observed at low or high dosages, respectively. Additional iron ions greatly promoted the photooxidation, but excessive amounts of Fe2+competed with As(Ⅲ) for oxidation by ROS. Experiments on scavengers indicated that the HOUradical was the predominant oxidant in this system.Experiments on actual soil surfaces proved the occurrence of As(Ⅲ) photooxidation in real topsoil. This work demonstrates that the photooxidation process of As(Ⅲ) on the soil surface should be taken into account when studying the fate of arsenic in natural soil newly polluted with acidic wastewater containing As(Ⅲ). | Wei Ding Yajie Wang Yingtan Yu Xiangzhi Zhang Jinjun Li Feng Wu | 2015 | Journal of Environmental Sciences2015，27，10： | 4 |
| 7 | Multiple transformation pathways of p-arsanilic acid to inorganic arsenic species in water during UV disinfection显示文摘p-Arsanilic acid(p-ASA) is widely used in China as livestock and poultry feed additive for promoting animal growth.The use of organoarsenics poses a potential threat to the environment because it is mostly excreted by animals in its original form and can be transformed by UV–Vis light excitation.This work examined the initial rate and efficiency of p-ASA phototransformation under UV-C disinfection lamp.Several factors influencing p-ASA phototransformation,namely,p H,initial concentration,temperature,as well as the presence of Na Cl,NH4+,and humic acid,were investigated.Quenching experiments and LC–MS were performed to investigate the mechanism of p-ASA phototransformation.Results show that p-ASA was decomposed to inorganic arsenic(including As(Ⅲ) and As(V))and aromatic products by UV-C light through direct photolysis and indirect oxidation.The oxidation efficency of p-ASA by direct photosis was about 32%,and those by HOU and1O2 were 19% and 49%,respectively.Cleavage of the arsenic–benzene bond through direct photolysis,HOU oxidation or1O2 oxidation results in simultaneous formation of inorganic As(Ⅲ),As(IV),and As(V).Inorganic As(Ⅲ) is oxidized to As(IV) and then to As(V) by1O2 or HOU.As(IV) can undergo dismutation or simply react with oxygen to produce As(V) as well.Reactions of the organic moieties of p-ASA produce aniline,aminophenol and azobenzene derivatives as main products.The photoconvertible property of p-ASA implies that UV disinfection of wastewaters from poultry and swine farms containing p-ASA poses a potential threat to the ecosystem,especially agricultural environments. | Suqi Li Jing Xu Wei Chen Yingtan Yu Zizheng Liu Jinjun Li Feng Wu | 2016 | Journal of Environmental Sciences2016，28，9： | 4 |
| 8 | Mesoporous iron oxide-silica supported gold catalysts for low-temperature CO oxidation显示文摘Mesoporous iron oxide-silica composite with a high silica content was synthesized by hydrothermal method,and another composite material with a high iron content was obtained by etching part of silica in alkaline solution.Gold catalysts were loaded onto both composites by a deposition-precipitation method,and used for CO oxidation.The samples were characterized by BrumauerEmmet-Teller(BET),X-ray diffraction(XRD),X-ray photoelectron spectra(XPS),transmission electron microscope(TEM)and scanning electron microscope(SEM)techniques.Both composites had high specific surface areas and were amorphous.The Au nanoparticles dispersed on the surface of the composites existed in metallic state.Composite with high silica content was not suitable for Au loading,and its supported gold catalyst showed poor performance in catalytic reaction.In contrast,composite with high iron content allowed efficient Au loading,and CO could be oxidized completely at low temperature on its supported gold catalyst.The effects of deposition-precipitation pH values on Au loading and activity of the catalyst were investigated,and the results indicated that Au loading was the highest and the catalyst was the most active for CO oxidation when the synthesis pH was adjusted to 8. | Weidong Zhang Xiaofei Lu Weili Zhou Feng Wu Jinjun Li | 2014 | Chinese Science Bulletin2014，59，31： | 3 |
| 9 | Experimental and numerical investigation of threedimensional vortex structures of a pitching airfoil at a transitional Reynolds number显示文摘This research examines the vortex behaviors and aerodynamic forces in dynamic stall phenomena at a transitional Reynolds number(Re=90000)using experimental and numerical approaches.Periodic sinusoidal pitching motion at two different reduced frequencies is used to achieve the dynamic stall of a NACA 0012 airfoil.Several leading edge vortices form and detach in the dynamic stall stage.The flow then quickly transitions to a full separation zone in the stall stage when the angle of attack starts to decrease.There is discrepancy between the phaseaveraged and instantaneous flow field in that the small flow structures increased with angle of attack,which is a characteristic of the flow field at the transitional Reynolds number.The interaction between the streamwise vortices in the three-dimensional numerical results and the leading edge vortex are the main contribution to the turbulent flow.In addition,the leading edge vortex that supplies vortex lift is more stable at higher reduced frequency,which decreases the lift fluctuation in the dynamic stall stage.The leading edge vortex at higher reduced frequency is strong enough to stabilize the flow,even when the airfoil is in the down-stroke phase. | Zhenyao LI Lihao FENG Hamid Reza KARBASIAN Jinjun WANG Kyung Chun KIM | 2019 | Chinese Journal of Aeronautics2019，32，10： | 2 |
| 10 | Al_2O_3-Coated Nano-SiC Particles Reinforced Al_2O_3 Matrix Composites显示文摘Properties of Al2O3-coated nano-SiC have been compared with those of as-received SiC. The isoelectric point (IEP)of SiC changed from pH3.4 to pH7.3 after coating with the alumina precursor, which is close to that of alumina.Because both surfaces of coated SiC and Al2O3 possess higher positive charge at pH=4.5~5.0, they are uniformly dispersed in the two-phase aqueous suspensions, Then a mixed powder containing nano-SiC dispersed homogeneously into the Al2O3 matrix was achieved from flocculating the two-phase suspension. Finally, Al2O3/SiC nanocomposites were obtained by coating nano-SiC with Al2O3, in which the majority of SiC particles were located within the Al2O3 grains. The observation by transmission electron microscopy (TEM) and the analysis by the X-ray photoelectron spectroscopy (XPS) showed that cracks propagated towards the intragranular SiC rather than along grain boundaries. | Juxian ZHANG, Jinjun FENG and Longqiao GAOBeijing Vacuum Electronics Research Institute, PO. Box 749 Ext. Box 33, Beijing 100016, China | 2002 | Journal of Materials Science & Technology2002，18，6： | 2 |
| 11 | The Research on Forestry Biomass Based on 3D Laser Scanning Technology显示文摘 | Cheng He Zhongke Feng Jinjun | | 0，，05： | 1 |
| 12 | Study of High Frequency Folded Waveguide BWO with MEMS Technology显示文摘 | Feng Jinjun Ren Dapeng Li Hanyan | | 0，，04： | 1 |
| 13 | New Algorithm Rules Out Acute-on-chronic Liver Failure Development within 28 Days from Acute Decompensation of Cirrhosis显示文摘Background and Aims:Approximately 10%of patients with acute decompensated(AD)cirrhosis develop acute-on-chronic liver failure(ACLF)within 28 days.Such cases have high mortality and are difficult to predict.Therefore,we aimed to establish and validate an algorithm to identify these patients on hospitalization.Methods:Hospitalized patients with AD who developed ACLF within 28 days were considered pre-ACLF.Organ dysfunction was defined accord-ing to the chronic liver failure-sequential organ failure as-sessment(CLIF-SOFA)criteria,and proven bacterial infec-tion was taken to indicate immune system dysfunction.A retrospective multicenter cohort and prospective one were used to derive and to validate the potential algorithm,re-spectively.A miss rate of<5%was acceptable for the calcu-lating algorithm to rule out pre-ACLF.Results:In the deri-vation cohort(n=673),46 patients developed ACLF within 28 days.Serum total bilirubin,creatinine,international normalized ratio,and present proven bacterial infection at admission were associated with the development of ACLF.AD patients with≥2 organ dysfunctions had a higher risk for pre-ACLF patients[odds ratio=16.58195%confidence interval:(4.271-64.363),p<0.001].In the derivation co-hort,67.5%of patients(454/673)had≤1 organ dysfunction and two patients(0.4%)were pre-ACLF,with a miss rate of 4.3%(missed/total,2/46).In the validation cohort,65.9%of patients(914/1388)had≤1 organ dysfunction,and four(0.3%)of them were pre-ACLF,with a miss rate of 3.4%(missed/total,4/117).Conclusions:AD patients with≤1 organ dysfunction had a significantly lower risk of developing ACLF within 28 days of admission and could be safely ruled out with a pre-ACLF miss rate of<5%. | Xiaoting Tang Hai Li Guohong Deng Xin Zheng Xianbo Wang Yan Huang Yanhang Gao Zhongji Meng Zhiping Qian Feng Liu Xiaobo Lu Yu Shi Beiling Li Wenyi Gu Xiaomei Xiang Yan Xiong Yixin Hou Jun Chen Na Gao Sen Luo Liujuan Ji Jing Li Rongjiong Zheng Haotang Ren Jinjun Chen | 2023 | Journal of Clinical and Translational Hepatology2023，11，3： | 1 |
| 14 | Impedance specifica- tions for stable DC distributed power system显示文摘 | FENG XIAOGANG LIU JINJUN LEE F C | 2002 | IEEE Transactions on Power Electronics2002，17，2： | 1 |
| 15 | Composite diamond films for short-mm wave and THz traveling wave tube windows显示文摘 | Ming Q. Ding Lili Li Jinjun Feng | 2014 | Diamond & Related Materials2014，，： | 1 |
| 16 | Study of High Frequency Folded Waveguide BWO with MEMS Technology显示文摘 | FENG Jinjun REN Dapeng LI Hanyan | | 0，，04： | 1 |
| 17 | Impedance specifications for stable DC distributed power systems显示文摘 | Feng Xiaogang Liu Jinjun Lee F C | 2002 | IEEE Transactions on Power Electronics2002，17，2： | 1 |
| 18 | A study of high-quality freestanding diamond films grown by MPCVD显示文摘 | Ming Q. Ding Lili Li Jinjun Feng | 2012 | Applied Surface Science2012，，16： | 1 |
| 19 | Individual influence of pitching and plunging motions on flow structures over an airfoil during dynamic stall显示文摘The individual influence of pitching and plunging motions on flow structures is studied experimentally by changing the phase lag between the geometrical angle of attack and the plunging angle of attack.Five phase lags are chosen as the experimental parameters,while the Strouhal number,the reduced frequency and the Reynolds number are fixed.During the motion of the airfoil,the leading edge vortex,the reattached vortex and the secondary vortex are observed in the flow field.The leading edge vortex is found to be the main flow structure through the proper orthogonal decomposition.The increase of phase lag results in the increase of the leading edge velocity,which strongly influences the leading edge shear layer and the leading edge vortex.The plunging motion contributes to the development of the leading edge shear layer,while the pitching motion is the key reason for instability of the leading edge shear layer.It is also found that a certain increase of phase lag,around 34.15°in this research,can increase the airfoil lift. | Zhenyao LI Lihao FENG Jinjun WANG | 2020 | Chinese Journal of Aeronautics2020，33，3： | 1 |
| 20 | Folded waveguide slow wave structure with modified circular bends显示文摘 | CAI Jun FENG Jinjun WU Xianping | 2014 | IEEETransactions on Electron Devices2014，61，10： | 1 |
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