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Molecular simulation study of the microstructures and properties of pyridinium ionic liquid[HPy][BF_(4)]mixed with acetonitrile

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原子与分子物理学报 2025年第4期42卷 27-32页

作者： XU jian-Qiang MA Zhao-Peng cheng Si LIU Zhi-Cong ZHU Guang-Lai Department of Physics School of Physics and Electronic InformationAnhui Normal UniversityWuhu 241002China

The microstructures and thermodynamic properties of mixed systems comprising pyridinium ionic liquid[HPy][BF_(4)]and acetonitrile at different mole fractions were studied using molecular dynamics simulation in this *** following properties were determined:density,self-diffusion coefficient,excess molar volume,and radial distribution *** results show that with an increase in the mole fraction of[HPy][BF_(4)],the self-diffusion coefficient ***,the excess molar volume initially decreases,reaches a minimum,and then *** rules of radial distribution functions(RDFs)of characteristic atoms are *** increasing the mole fraction of[HPy][BF_(4)],the first peak of the RDFs of HA1-F decreases,while that of CT6-CT6 rises at first and then *** indicates that the solvent molecules affect the polar and non-polar regions of[HPy][BF_(4)]differently.

关键词： Pyridinium ionic liquids Thermodynamic properties Molecular dynamics simulation Radial distribution functions

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制造业数字化转型与绿色技术创新的关系研究

工业技术经济 2025年第1期44卷 115-121页

作者：成新轩丰义李明峰河北大学经济学院保定071002 河北经贸大学工商管理学院石家庄050000

为深入探究数字化转型与制造业绿色技术创新之间的关系,本文以2013~2023年全国制造业为研究对象,开展制造业数字化转型与绿色技术创新的关系实证研究。以制造业绿色技术创新效率为因变量,以制造业数字化转型水平为自变量,以行业规模、... 详细信息

为深入探究数字化转型与制造业绿色技术创新之间的关系,本文以2013~2023年全国制造业为研究对象,开展制造业数字化转型与绿色技术创新的关系实证研究。以制造业绿色技术创新效率为因变量,以制造业数字化转型水平为自变量,以行业规模、资本强度、融资能力、外资投入比、技术成熟度为控制变量,通过回归分析、稳健性、异质性检验等,验证因变量与自变量之间的关系。结果表明:数字化转型显著促进了制造业绿色技术创新,且行业规模越大和资本强度越强的制造业,其绿色技术创新效率越高;数字化转型对出口依赖度、发展阶段、数字化来源、行业要素不同的制造业促进效果不同,对出口依赖度高、发展阶段靠前、国际数字化来源和高技术创新的制造业绿色技术创新促进作用更强;数字化转型可通过减少外部交易成本和提高市场竞争的方式,促进制造业绿色技术的创新。为提高制造业绿色技术创新,本文提出包含加强行业市场竞争力和加强政府监管等策略,以期能够更好地发挥数字化转型对制造业绿色技术创新的促进作用。

关键词：数字化制造业技术创新效率稳健性异质性行业市场竞争力政府监管

Experimental study of dual nano-network, high-temperature resistant aerogel material as an integration of thermal management functions

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journal of Energy Chemistry 2025年第1期 157-170页

作者： Yueyue Xiao Tianke Mao Zun Zhao Yuelei Pan Heping Zhang Xudong cheng State Key Laboratory of Fire Science University of Science and Technology of China

Thermal management system is highly desirable to guarantee the performance and thermal safety of lithium-ion batteries,but it reduces the energy density of battery modules and even is unable to provide highly effective ***,a thermal management function integrated material is presented based on high-temperature resistant aerogel and phase change material and is applied at both charge–discharge process and thermal runaway *** this sandwich structure Paraffin@SiC nanowire/Aerogel sheet （denoted as PA@SAS） system,SiC nanowires endow the middle aerogel sheet （SAS） a dual nano-network *** enhanced mechanical properties of SAS were studied by compressive tests and dynamic mechanical ***,the thermal conductivity of SAS at 600°C is only 0.042 W/（m K）.The surface phase change material layers facilitate temperature uniformity of batteries （surface temperature difference less than 1.82°C） through latent ***,a large-format battery module with four 58 Ah LiNi0.5Co0.2Mn0.3O2LIBs was ***@SAS successfully prevents thermal runaway propagation,yielding a temperature gap of 602°C through the 2 mm-thick cross ***@SAS also exhibits excellent performance in other safety issues such as temperature rise rate,flame heat flux,*** lightweight property and effective insulation performance achieves significant safety enhancement with mass and volume energy density reduction of only 0.79%and 5.4%,*** originality of the present research stems from the micro and macro structure design of the proposed thermal management material and the combination of intrinsic advantages of every *** work provides a reliable design of achieving the integration of thermal management functions into an aerogel composite and improves the thermal safety of lithium-ion batteries.

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基于网络虚拟展示的农机工业设计研究

农机化研究 2025年第3期47卷 186-191页

作者：尹程黄月芹覃祚萍柳州工学院广西柳州545616 柳州职业技术学院广西柳州545006

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农... 详细信息

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农业机械的外观及色彩要素进行分析,以提高农户使用体验感为主要研究目标对农业机械设计流程进行阐述,最终以虚拟仿真的形式将最终优化设计效果进行展示,形成完善的农业机械优化设计流程。研究结果可以为农业机械产品的设计提供技术指导与理论支撑。

关键词：虚拟仿真 CMF 设计展示

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An integration method based on a novel combined flow for aerodynamic configuration of strutjet engine

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Chinese journal of Aeronautics 2021年第9期34卷 156-167页

作者： Longsheng XUE Chuan cheng chengpeng WANG Keming cheng College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China Aerospace System Engineering Shanghai Shanghai 201100China

In this paper a novel design method of aerodynamic configuration is proposed to integrate forebody,strut and inlet for strutjet engine,and a model at design point of Mach number6 is generated to investigate the aerodynamic performance by both simulations and *** basic flow field employed by proposed method is a combined flow named IBB,which is combined by Internal Conical Flow A(ICFA),truncated Busemann flow I(BI)for external section,and truncated Busemann flow II(BII)for internal *** model configuration is generated by streamline tracing method from basic flow field,in which the forebody section is traced from ICFA and BI flows,and the inlet as well as strut section is traced from BII *** simulations in Mach number 4,5,and 6 demonstrate uniform starting flow fields with relatively high total pressure recovery,which agree well with experiments in wind ***,in low Mach number cases,this inlet could start at Mach number 3 while it is unstarted at Mach number 2.7;in high Mach number cases,a uniform flow could still exist in Mach number 6.5 while a relatively strong shock wave boundary layer interaction is found in cowl area of Mach number 7 case,indicating the inlet designed by proposed method works in a relatively wide Mach number range.

关键词： Airframe-propulsion integration Busemann flow Combined flow Hypersonics Wind tunnel test

Numerical investigation of low cycle fatigue life for channel wall nozzles

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航空动力学报 2018年第7期33卷 1553-1565页

作者： cheng cheng WANG Yibai LIU Yu LIN Qingguo Research and Development Center Shanghai Institute of Space Propulsion Shanghai 201112 China Shanghai Engineering Research Center of Space Engine Shanghai 201112 China School of Astronautics Beijing University of Aeronautics and Astronautics

The thermal-structural response and low cycle fatigue life of a three-dimensional(3D)channel wall nozzle with regenerative cooling were numerically investigated by coupling the finite volume fluid-thermal method,nonlinear finite element thermal-structural analysis and local strain *** nozzle had a high area ratio(nozzle exit area divided by throat area)under cyclic working *** studies were carried out to evaluate the effects of channel structural parameters such as channel width,channel height,liner thickness and rib *** showed that the integrated effects of three-dimensional channel structure and load distribution caused serious strain,which mainly occurred at the intersectant regions of liner wall on the gas side and the symmetric planes of channel and *** cooling effect and channel structural strength were significantly improved as the channel width and height decreased,leading to substantial extension of the nozzle service *** the other hand,the successive decrease in liner thickness and rib width apparently increased the strain amplitude and residual strain of channel wall nozzle during cyclic work,significantly shortening the service *** present work is of value for design of the channel wall nozzle to prolong its cyclic service life.

关键词： liquid propellant rocket engine low cycle fatigue channel wall nozzle regenerative cooling nonlinear structural analysis finite element method

Numerical investigation on cooling performance of filter in a pyrotechnic gas generator

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Defence Technology（防务技术） 2021年第2期17卷 343-351页

作者： cheng cheng Xiaobing Zhang Chong Wang Lu Wang School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China

As a key part of the pyrotechnic gas generator,the filter not only removes the particulate matter but also cools the hot gas to a safe *** paper aims to improve the understanding of the basic heat and flow phenomenon in the gas *** pyrotechnic gas generator is modelling by a simplified filter structure with fiber arrays.A finite-volume model of the heat and fluid flow is proposed to simulate the detailed multi-dimensional flow and energy conversion *** verification results are in good agreement with data in different *** results demonstrate that the filter can not only absorb heat from the gas but also cause the high intensity enhancement of the heat *** performance difference between inline and staggered arrays is also *** findings of the study put a further prediction tool for the understanding and design of the filter system with fibers.

关键词： Pyrotechnic gas generator Cooling performance Filter Metal fiber

Singularity of lithosphere mass density over the mid-ocean ridges and implication on floor depth and heat flow

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Geoscience Frontiers 2023年第5期14卷 55-71页

作者： Qiuming cheng State Key Lab of Geological Processes and Mineral Resources China University of Geosciences(Bejing)Beijing 100083China School of Earth Science and Engineering Sun Yat-sen UniversityZhuhai 519000China

The relation of heat flow and floor depth across the mid-ocean ridges versus lithosphere age can be described by linear functions of square root of age according to plate thermal conductive Half Space Models(HSM).However,one of the long-standing problems of these classical models is the discrepancies between predicted and observed heat flow and floor depth for very young and very old *** have been several recent attempts to overcome this problem:one model incorporates temperature-and pressure-dependent parameters and the second model includes an additional low-conductivity crustal layer or magma rich mantle layer(MRM).Alternatively,in the current paper,the ordinary density of lithosphere in the plate conductive models is substituted with a reduction of lithosphere density towards axis that features the irregularity and nonlinearity of plates across the mid-ocean ridges.A new model is formulated incorporating the new form of density for predicting both peak heat flow and floor *** solutions of power-law forms derived from the model can significantly improve the predicting results of heat flow and floor depth over the mid-ocean *** datasets in the literature were reutilized for model validation and *** datasets include both earlier datasets used for original model calibration and the more recently compiled high-quality datasets with both sedimentary and crustal loading *** results indicate that both the heat flow and the slope(first orderderivative)of sea floor approach infinity(undifferentiability or singularities)around the mid-ocean *** singularities are partially due to the boundary condition as it has been already known in the literature and partially to the reduction of density of lithosphere as discovered for the first time in the current research.

关键词： Mid-ocean ridges Plate cooling model Lithosphere density Conductive model Heat-flow Floor depth

Precoding Based Channel Prediction for Underwater Acoustic OFDM

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China Ocean Engineering 2017年第2期31卷 256-260页

作者： cheng En School of Information Science and Engineering Xiamen University Xiamen 361005 China Key Laboratory of Underwater Acoustic Communication and Marine Information Technology (Xiamen University) Ministry of Education Xiamen 361005 China Science and Technology on Underwater Acoustic Antagonizing Laboratory Beijing 100094 China

The life duration of underwater cooperative network has been the hot topic in recent years. And the problem of node energy consuming is the key technology to maintain the energy balance among all nodes. To ensure energy efficiency of some special nodes and obtain a longer lifetime of the underwater cooperative network, this paper focuses on adopting precoding strategy to preprocess the signal at the transmitter and simplify the receiver structure. Meanwhile, it takes into account the presence of Doppler shifts and long feedback transmission delay in an underwater acoustic communication system. Precoding technique is applied based on channel prediction to realize energy saving and improve system performance. Different precoding methods are compared. Simulated results and experimental results show that the proposed scheme has a better performance, and it can provide a simple receiver and realize energy saving for some special nodes in a cooperative communication.

关键词： underwater acoustic communication precoding channel prediction CFO OFDM