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Characteristics of compressible flow of supercritical kerosene

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Acta Mechanica Sinica 2012年第1期28卷 8-13页

作者： feng-quan zhong Xue-Jun Fan Jing Wang Gong Yu Jian-Guo Li Institute of Mechanics Chinese Academy of Sciences100190 BeijingChina

In this paper, compressible flow of aviation kerosene at supercritical conditions has been studied both numerically and experimentally. The thermophysical properties of supercritical kerosene are calculated using a 10- species surrogate based on the principle of extended corresponding states （ECS）. Isentropic acceleration of supercritical kerosene to subsonic and supersonic speeds has been analyzed numerically. It has been found that the isentropic relationships of supercritical kerosene are significantly dif- ferent from those of ideal gases, A two-stage fuel heating and delivery system is used to heat the kerosene up to a tem- perature of 820 K and pressure of 5.5 MPa with a maximum mass flow rate of 100 g/s. The characteristics of supercritical kerosene flows in a converging-diverging nozzle （Laval nozzle） have been studied experimentally. The results show that stable supersonic flows of kerosene could be established in the temperature range of 730 K-820 K and the measurements in the wall pressure agree with the numerical calculation.

关键词： Supercritical kerosene - Compressible flow Laval nozzle Isentropic process

Performance of supersonic model combustors with staged injections of supercritical aviation kerosene

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Acta Mechanica Sinica 2010年第5期26卷 661-668页

作者： feng-quan zhong Xue-Jun Fan Gong Yu Jian-Guo Li Chih-Jen Sung LHD Institute of Mechanics Chinese Academy of Sciences100190 Beijing China University of Connecticut Storrs CT 06269 USA

Supersonic model combustors using two-stage injections of supercritical kerosene were experimentally investigated in both Mach 2.5 and 3.0 model combustors with stagnation temperatures of approximately 1,750 K. Supercritical kerosene of approximately 760 K was prepared and injected in the overall equivalence ratio range of 0.5-1.46. Two pairs of integrated injector/flameholder cavity modules in tandem were used to facilitate fuel-air mixing and stable combustion. For single-stage fuel injection at an upstream location, it was found that the boundary layer separation could propagate into the isolator with increasing fuel equivalence ratio due to excessive local heat release, which in turns changed the entry airflow conditions. Moving the fuel injection to a further downstream location could alleviate the problem, while it would result in a decrease in combustion efficiency due to shorter fuel residence time. With two-stage fuel injections the overall combustor performance was shown to be improved and kerosene injections at fuel rich conditions could be reached without the upstream propagation of the boundary layer separation into the isolator. Furthermore, effects of the entry Mach number and pilot hydrogen on combustion performance were also studied.

关键词： Supersonic combustion Staged injection Combustion efficiency Supercritical kerosene

Large Eddy Simulation of Stratified Turbulent Channel Flow with a Dynamic Subgrid Scale Model

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Advances in Manufacturing 2000年第2期4卷 87-91页

作者： feng-quan zhong Nan-sheng Liu Xi-yun Lu Bing-gang Tong Department of Mechanics and Mechanical Engineering University of Science and Technology of China Hefei China

In this paper, large eddy simulation coupled with a dynamic subgrid scale (SGS) model is used to study turbulent channel flows with heat transfer. Some fundamental flow behaviors are discussed. Based on our calculated results, the dynamic SGS model can reasonably predict some main characteristics of stratified turbulent channel flows. Our results are also in good agreement with theoretical analyses and previous calculated results.

关键词： large eddy simulation (LES) subgrid scale (SGS) model stratified turbulence heat transfer

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直升机结构振动频域主动控制的时域仿真

系统仿真学报 2009年第20期21卷 6347-6351页

作者：赵灿峰顾仲权南京航空航天大学直升机旋翼动力学重点实验室南京210016

降低直升机的振动水平一直是直升机研制过程中最为关键的技术问题之一。研究直升机结构振动主动控制的频域控制算法和流程,并基于某型直升机空测数据与其控制通道频响函数实测数据,进行从时域到频域再返回时域的振动控制全过程的仿真,... 详细信息

降低直升机的振动水平一直是直升机研制过程中最为关键的技术问题之一。研究直升机结构振动主动控制的频域控制算法和流程,并基于某型直升机空测数据与其控制通道频响函数实测数据,进行从时域到频域再返回时域的振动控制全过程的仿真,探讨与比较在线系统参数识别的两种方法(最小均方法和卡尔曼滤波法)、频域法的时域控制中重要参数的设置等,得出有价值的结论,为真实工程应用中方法的选择提供参考和依据。

关键词：直升机结构响应主动控制最小均方法卡尔曼滤波参数识别

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-feng Wang Wen-Jie Shi Yu-Xin Yang Bao-Xia Dong Tong-Bu Lu Di-Chang zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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Unraveling the mechanism of action of Shangxia Liangji formula for treating insomnia:a metabolomics and network pharmacology approach

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Traditional Medicine Research 2025年第2期10卷 16-29页

作者： Xia-Jie quan Hao Liang Yong-Hong Tang Li Jiang Xiong-Ying Ji feng-Ying Zhang Ping Zhang Bo Ouyang Department of Information The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Neurology The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Gastroscopy The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China Department of Traditional Chinese Medicine The Affiliated Nanhua HospitalHengyang Medical SchoolUniversity of South ChinaHengyang 421002China

Background:Insomnia is a prevalent clinical condition and Shangxia Liangji formula(SXLJF)is a well-established method of ***,the specific mechanism of action of SXLJF remains ***:The mouse model of insomnia was established by intraperitoneal injection of ***-two mice were randomly divided into a negative control group,model group,SXLJF group(18.72 g/kg/day),and positive control group(diazepam,2 mg/kg)and treated with the corresponding drugs for 7 consecutive *** open field test and pentobarbital-induced sleeping test were ***-MS-based untargeted metabolomics and network pharmacology were applied to explore the potential targets of SXLJF for treating ***,key targets were validated using ***:Behavioral tests demonstrated that SXLJF reduced the total distance,average velocity,central distance,and sleep latency,and prolonged sleep *** and network pharmacology revealed potential targets,signaling pathways,metabolic pathways,and metabolites associated with the anti-insomnia effects of ***,tyrosine hydroxylase(TH)and tyrosine metabolism emerged as crucial metabolic pathways and targets,***-qPCR results supported the role of TH in the mechanism of SXLJF in treating ***:In conclusion,TH and tyrosine metabolism may represent significant targets and pathways for SXLJF in treating insomnia.

关键词： Shangxia Liangji formula insomnia metabolomics network pharmacology tyrosine hydroxylase tyrosine metabolism

A New Tetra-nuclear Nd(Ⅲ) Coordination Polymer Based on Linear Azide and Isonicotinate Anions: Synthesis, Thermal Stability and Near-infrared Luminescent Properties

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Chinese Journal of Structural Chemistry 2020年第11期39卷 2046-2052页

作者： zhong Zhi-Guo LI Jing feng Yu-quan College of Chemistry and Pharmacy Engineering Nanyang Normal UniversityNanyang 473061China

A novel tetra-nuclear Nd(Ⅲ) coordination polymer, Nd4(μ3-OH)4(μ2-H2O)2(C6H4NO2)6(N3)2(H2O)2(1, C6H4N zide anion), was successfully prepared under hydrothermal conditions and fully characterized by C, H and N elemental analysis, IR spectrum, thermal stability and single-crystal X-ray diffraction. It crystallizes in the triclinic system, space group P1, with Z = 1, a = 8.188(3), b = 12.516(5), c = 12.573(5) ?, α = 107.887(1)°, β = 104.681(2)°, γ = 98.086(6)°, V = 1152.2(8) ?3, M3 r = 1533.73, Dc = 2.210 g/cm, λ = 0.71073 ?, μ = 4.524 mm-1, F(000) = 736, R = 0.0332 and wR = 0.0901 for 3954 observed reflections with Ⅰ > 2σ(Ⅰ) and S = 1.071. The molecular structure of polymer 1 is constructed by four Nd3+ cations, four bridging μ3-OH- anions, two bridging μ2-H2 O, six C6 H4 NO2- anions, two linear azide anions and two coordinated water molecules. The structure of polymer 1 can be viewed as a 3-D supra-molecular network constructed by O-H···O and O-H···N hydrogen bonds between the adjacent chains. Moreover, its near-infrared luminescence and luminescence quenching for Cu2+ cation have also been investigated in detail.

关键词： tetra-nuclear Nd(Ⅲ)polymer linear azide anion thermal stability near-infrared fluorescent properties

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青年急性脑梗死的MRA特点及其临床价值

磁共振成像 2016年第6期7卷 428-432页

作者：冯中全洪斌钱伟军朱丽娟蒋忠仆开封市中心医院磁共振科开封475000 开封市中心医院神经内科开封475000

目的分析青年急性脑梗死的磁共振血管成像(magnetic resonance angiography,MRA)表现特点,探讨其临床价值。材料与方法回顾性对比分析149例青年急性脑梗死及187例中老年急性脑梗死的MRA表现。结果青年脑梗死MRA表现正常率高于中老年组,... 详细信息

目的分析青年急性脑梗死的磁共振血管成像(magnetic resonance angiography,MRA)表现特点,探讨其临床价值。材料与方法回顾性对比分析149例青年急性脑梗死及187例中老年急性脑梗死的MRA表现。结果青年脑梗死MRA表现正常率高于中老年组,局限性靶血管异常高于中老年组,动脉硬化性靶血管异常低于中老年组,靶血管阳性患者预后好于中老年组(P<0.05)。结论青年脑梗死与中老年脑梗死的MRA表现差异性很大,应及时分析病因及危险因素,采取不同的措施做好治疗及防范。

关键词：青年脑梗死,急性磁共振血管成像