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航空动力学报 2017年第5期32卷 1183-1194页

作者： YANG Ling ZHONG jing-jun han ji-ang Marine Engineering College Dalian Maritime University

The design methods of typical supersonic aircraft intakes and shock wave compression technology have been applied to ram-rotor,an attractive compression system.A ram-rotor is of a typical structure including the compression ramp,the throat and the subsonic diffuser;a scrampressor is similar to ram-rotor,the only difference is that scrampressor has no subsonic *** work was the continuation of the preparatory *** order to further study the effect of throat contraction ratio and strake stagger angle on the flow field and performance of a scrampressor,the flow field of a scrampressor with a three-dimensional flow path was numerically simulated with different throat contraction ratios and strake stagger *** results indicated that the optional aerodynamic performance of a scrampressor could be achieved with an adiabatic efficiency of 0.8413atotal pressure recovery coefficient of 0.8446,a total pressure ratio of 7.14 and a static pressure ratio of 5.17for a throat contraction ratio of 0.6 and a strake stagger angle of 12°.It was therefore concluded that an appropriate decrease in throat contraction ratio and an increase in strake stagger angle could help the comprehensive improvement of a scrampressor in performance.

关键词： scrampressor flow field aerodynamic performance throat contraction ratio strake stagger angle

Estimation of solid concentration in solid-liquid two-phase flow in horizontal pipeline using inverse-problem approach

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Particuology 2022年第3期20卷 1-13页

作者： ji Zhang han Yuan Ning Mei Zhe Yan Marine Engineering College of EngineeringOcean University of ChinaQingdao 266100China Offshore Engineering Department of CivilEnvironmental and MiningUniversity of Western Australia35 Stirling HwyCrawleyWA 6009Australia Power Engineering and Engineering Thermophysics School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this study,an inverse-problem method was applied to estimate the solid concentration in a solid-liquid two-phase *** algebraic slip mixture model was introduced to solve the forward problem of solid-liquid convective heat *** time-average conservation equations of mass,momentum,energy,as well as the volume fraction equation were computed in a computational fluid dynamics(CFD)*** solid concentration in the CFD model was controlled using an external program that included the inversion iteration,and an optimal estimation was performed via experimental *** using a fly-ash-water mixture and sand-water mixture with different solid concentrations in a horizontal pipeline were conducted to verify the accuracy of the inverse-problem *** estimated results were rectified using a method based on the relationship between the estimated results and estimation error;consequently,the accuracy of the corrected inversion results improved *** a verification through experiments,the inverse-problem method was concluded to be feasible for predicting the solid concentration,as the estimation error of the corrected results was within 7%for all experimental samples for a solid concentration of less than 50%.The inverse-problem method is expected to provide accurate predictions of the solid concentration in solid-liquid two-phase flow systems.

关键词： Solid-liquid two-phase flow Solid concentration estimation Coupling calculation Inverse heat transfer problem Algebraic slip mixture model

A cellulose-based lithium-ion battery separator with regulated ionic transport and high thermal stability for extreme environments

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Nano Research 2025年第1期18卷 315-322页

作者： Kun-Peng Yang Song Xie Zi-Meng han Hao-Cheng Liu Chong-han Yin Wen-Bin sun Zhang-Chi Ling Huai-Bin Yang De-han Li Qing-Fang Guan Shu-Hong Yu Department of Chemistry New Cornerstone Science LaboratoryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsDivision of Nanomaterials&ChemistryHefei National Research Center for Physical Sciences at the MicroscaleUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

Separators play a critical role in lithium-ion ***,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh ***,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and *** an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion *** addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.

关键词： lithium-ion batteries bio-inspired materials battery separators cellulose nanofiber ultrahigh ionic conductivity high safety

Hot Workability of the as-Cast 21Cr Economical Duplex Stainless Steel Through Processing Map and Microstructural Studies Using Different Instability Criteria

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Acta Metallurgica Sinica(English Letters) 2017年第11期30卷 1080-1088页

作者： jing han jia-Peng sun Ying han Huan Liu School of Mechanical and Electrical Engineering China University of Mining and Technology College of Mechanics and Materials Hohai University Key Laboratory of Advanced Structural Materials Ministry of EducationChangchun University of Technology

To develop a fundamental understanding of the flow behavior and optimal hot workability parameters of this material, the hot workability and deformation mechanisms of the as-cast 21Cr EDSS were studied using processing map technology combined with microstructure analysis and isothermal hot compression over the temperature range of 1000-1150 ℃ and strain rate range of 0.01-10 s-1. The processing maps and constitutive equation of peak stress were developed based on Prasad＇s and Murty＇s criteria. The results show that the processing maps exhibit a stable domain at 1000-1150 ℃ and 0.01-1 s-1. The instability domain is exhibited at high strain rates （≥1 s-l）. This implies that Murty＇s criterion can predict the unstable domain with high reliability. The detailed deformation mechanisms are also studied by microstructure observation, showing that the flow localization and microcracking are responsible for the flow instability.

关键词： Duplex stainless steel Constitutive relationship Processing map Hot deformation behavior

Influence of Copper on Transport and Dissipation of Lambda-Cyhalothrin and Cypermethrin in Soils

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Pedosphere 2013年第3期23卷 395-401页

作者： LIU Jun L Xiao-Meng XIE ji-Min LI Ping-Ping han jian-Gang sun Cheng School of the Environment Jiangsu University State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences School of Chemistry and Chemical Engineering Jiangsu University jiangsu Provincial Key Laboratory of Modern Agricultural Equipment and Technology Institute of Agricultural Engineering Jiangsu University State Key Lab of Pollution Control and Resource Reuse Nanjing University

Repeated applications of bordeaux mixture （a blend of copper sulfate and calcium hydroxide） and pyrethroid insecticides （Pys） have led to elevated copper （Cu） and Pys concentrations in vineyard surface soils. To understand the potential influence of Cu on the fate of Pys in the soil environment, we selected two Pys, cypermethrin （CPM） and lambda-cyhalothrin （A-CHT）, and two typical Chinese vineyard soils, Haplic Acrisol and Luvic Phaeozem, as experimental samples. The dissipation experiment was conducted at room temperature in the dark, and the transport of both Pys through the soils was investigated using soil thin-layer chromatography. The results showed that the transport of Pys in both soils increased as the Cu2＋ concentration increased from 0 to 100 mg L-1, and Pys were more transportable in Haplic Acrisol （HA） than in Luvic Phaeozem （LP） under the same experimental conditions. For CPM, only 100 mg L-1 of Cu2＋ significantly （P 〈 0.05） increased Pys transport through both soils relative to water. Lambda-CHT was significantly （P〈0.05） transported through HA by all the Cu2＋ concentrations compared to water, and all but the 1 mg L-1 of Cu2＋ significantly （P 〈 0.05） increased the transport of A-CHT through LP relative to water. However, the dissipation rates of CPM and λ-CHT decreased with the addition of Cu to soils. Our findings suggest that the risk of groundwater contamination by Pys increases in the soils with elevated Cu concentrations.

关键词： Haplic Acrisol Luvic Phaeozem potential ecological risk pyrethroid insecticides soil thin-layer chromatography

Hypergraph Computation

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Engineering 2024年第9期40卷 188-201页

作者： Yue Gao Shuyi ji Xiangmin han Qionghai Dai School of Software Tsinghua UniversityBeijing 100084China

Practical real-world scenarios such as the Internet,social networks,and biological networks present the challenges of data scarcity and complex correlations,which limit the applications of artificial *** graph structure is a typical tool used to formulate such correlations,it is incapable of modeling highorder correlations among different objects in systems;thus,the graph structure cannot fully convey the intricate correlations among *** with the aforementioned two challenges,hypergraph computation models high-order correlations among data,knowledge,and rules through hyperedges and leverages these high-order correlations to enhance the ***,hypergraph computation achieves collaborative computation using data and high-order correlations,thereby offering greater modeling *** particular,we introduce three types of hypergraph computation methods:①hypergraph structure modeling,②hypergraph semantic computing,and③efficient hypergraph *** then specify how to adopt hypergraph computation in practice by focusing on specific tasks such as three-dimensional(3D)object recognition,revealing that hypergraph computation can reduce the data requirement by 80%while achieving comparable performance or improve the performance by 52%given the same data,compared with a traditional data-based method.A comprehensive overview of the applications of hypergraph computation in diverse domains,such as intelligent medicine and computer vision,is also ***,we introduce an open-source deep learning library,DeepHypergraph(DHG),which can serve as a tool for the practical usage of hypergraph computation.

关键词： High-order correlation Hypergraph structure modeling Hypergraph semantic computing Efficient hypergraph computing Hypergraph computation framework

Heat Capacity and Thermodynamic Properties of Crystalline 2-Chloro- N, N-dimethylnicotinamide

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Chinese Journal of Chemistry 2005年第11期23卷 1490-1494页

作者： sun, Xiao-Hong LIU, Yuan-Fa TAN, Zhi-Cheng ji, Peng-Ju WANG, Mei-han College of Chemical Engineering Chemical Research Institute Northwest University Xi'an Shaanxi 710069 China Department of Chemistry Northwest University Xi'an Shaanxi 710069 China Thermochemistry Laboratory Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian Liaoning 116023 China

Low-temperature heat capacities of 2-chloro-N,N-dimethylnicotinamide were precisely measured with a high-precision automated adiabatic calorimeter over the temperature range from 82 K to 380 K. The compound was observed to melt at （342.15±0.04） K. The molar enthalpy AfusionHm, and entropy of fusion, △fusionSm, as well as the chemical purity of the compound were determined to be （21387±7） J·mol^-1, （62.51±0.01） J·mol^-1·K^-1, （0.9946±0.0005） mass fraction, respectively. The extrapolated melting temperature for the pure compound obtained from fractional melting experiments was （342.25±0.024） K. The thermodynamic function data relative to the reference temperature 298.15 K were calculated based on the heat capacity measurements in the temperature range from 82 to 325 K. The thermal behavior of the compound was also investigated by different scanning calorimetry.

关键词： 2-chloro-N,N-dimethylnicotinamide heat capacity adiabatic calorimetry

Effects of Expansion Chamber on the Flow Pattern and Performance of Cyclones

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China Petroleum Processing & Petrochemical Technology 2017年第2期19卷 114-122页

作者： han Xiao sun Guogang sun Zhanpeng han Xiaopeng State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 Beijing Key Laboratory of Process Fluid Filtration and Separation Beijing 102249

To improve the performance of the Stairmand cyclone, the effects of an expansion chamber on the flow field, the pressure drop and the separation efficiency were investigated numerically and experimentally. The experimental results showed that compared with the Stairmand cyclone, the cyclone with an upper expansion chamber worked better at low inlet velocity(less than 14 m/s in this study), while the cyclone with a lower expansion chamber achieved higher efficiency at a relatively high inlet velocity(14-20 m/s). The presence of an expansion chamber can generally result in a slight decrease in the cyclone pressure drop. The simulated results, which were used to further analyze the reason behind the experimental phenomena, suggested that the expansion chamber had insignificant effects on the tangential velocity profiles in the cylindrical part of cyclones. While in the cone part, the expansion chamber and the dipleg, the tangential velocity slightly decreased. Nevertheless, the expansion chamber decreased the possibility of the vortex end to sweep the wall and then reduce the particle re-entrainment. Therefore, installing the expansion chamber at a proper position could improve the separation performance of Stairmand cyclones. Both the experimental and simulated results represent a potential improvement of the Stairmand cyclone performance.

关键词： expansion chamber numerical simulation flow field separation efficiency

New ent-kaurane-type diterpenoids from Isodon nervosus

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Chinese Chemical Letters 2008年第4期19卷 441-443页

作者： Fu Lin Yan Lan Qing Guo ji Xia Zhang Su Ping Bai han Dong sun Pharmacy College Xinxiang Medical UniversityXinxiang 453003China Kunming Institute of Botany Chinese Academy of SciencesKunming 650204China

Two new ent-kaurane-type diterpenoids,6β,7β,13α-trihydroxy-1α-acetoxy-7α,20-epoxy-ent-kaur-16-en-15-one（1）and 15β- hydroxy-6,7-seco-6,11β：6,20-diepoxy-1α,7-olide-ent-kaur-16-ene（2）were isolated from the I... 详细信息

关键词： Labiatae Isodon nervosus ent-Kaurane diterpenoid

Triethylammonium picrate： An above-room-temperature phase transition material to switch quadratic nonlinear optical properties

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Chinese Chemical Letters 2018年第2期29卷 285-288页

作者： Muhammad Adnan Asghar jing Zhang Shiguo han Zhihua sun Chengmin ji Aurang Zeb Junhua Luo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou 350002 China University of the Chinese Academy of Sciences Beijing 100039 China

To switch quadratic nonlinear optical（NLO） effects has become an exciting branch of the NLO material science. However, solid-state molecular crystals showing tunable and switchable NLO behaviors remain scarce. Here, we report an organic picrate-based binary molecular crystal, triethylammonium picrate（TEAP）, which undergoes an above-room-temperature phase transition at T_c=319 K, being solidly confirmed by the thermal and dielectric measurements. A large thermal hysteresis of ~7 K discloses the first-order feature for its phase transition. More strikingly, the quadratic NLO effects of TEAP can be switched in the vicinity of Tc. That is, TEAP exhibits NLO-active response of ~1.5 times as large as that of KDP below T_c（i.e., NLO-on state）, while its NLO effects totally disappear above T_c（NLO-off state）. Structure analyses disclose that the order-disorder transformations of triethylammonium cations and picrate anions collectively contribute to its phase transition, as well as switchable NLO behaviors. This work opens up a new pathway to the designing and assembling of stimuli-responsive materials.

关键词： Phase transition Nonlinear optical properties Dielectric properties Order-disorder