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Defence Technology（防务技术） 2024年第1期31卷 400-416页

作者： Yu Tang Yiwan Wu hu cheng Rong Liu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350156China AECC Guizhou Liyang Aviation Power Co. LTDGuiyang 550014China College of Computer and Information Sciences Fujian Agriculture and Forestry UniversityFuzhou 350156China

Strong impact does serious harm to the military industries so it is necessary to choose reasonable cushioning material and design effective buffers to prevent the impact of equipment.Based on the capillary property entangled porous metallic wire materials(EPMWM),this paper designed a composite buffer which uses EPMWM and viscous fluid as cushioning materials under the low-speed impact of the recoil force device of weapon equipment(such as artillery,mortar,etc.).Combined with the capillary model,porosity,hydraulic diameter,maximum pore diameter and pore distribution were used to characterize the pore structure characteristics of EPMWM.The calculation model of the damping force of the composite buffer was established.The low-speed impact test of the composite buffer was conducted.The parameters of the buffer under low-speed impact were identified according to the model,and the nonlinear model of damping force was obtained.The test results show that the composite buffer with EPMWM and viscous fluid can absorb the impact energy from the recoil movement effectively,and provide a new method for the buffer design of weapon equipment(such as artillery,mortar,etc.).

关键词： Entangled porous metallic wire materials Capillary property Viscousfluid Low-speed impact Damping force

Sustainable production of high-energy-density jet fuel via cycloaddition reactions

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Journal of Energy Chemistry 2024年第8期95卷 712-722页

作者： Yan-cheng hu Yingying Zhao Ning Li Jing-Pei Cao School of Chemical Engineering and Technology China University of Mining and Technology School of Education Science Jiangsu Normal University CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Developing an energy supply-chain based on renewable biomass holds great potential to build a low carbon society. High-energy-density(HED) jet fuel, featuring unique fused/strained cycloalkanes, is of great significance for volume-limited military aircrafts, as their high density and combustion heat can extend flight duration and increase the payload. Therefore, the exploration of biomass-based routes towards HED fuel has drawn much attention over the past decade. Cycloaddition reaction features rapid construction of various carbocycles in an atom-and step-economical fashion. This elegant strategy has been widely applied in the manufacture of sustainable HED fuel. Here we carefully summarize the progress achieved in this fascinating area and the review is categorized by the cycloaddition patterns including [4+2], [2+2],[4+4], and [2+1] cycloadditions. Besides, the energy densities of the as-prepared biofuels and petroleumbased fuels(conventional Jet-A and advanced JP-10) are also compared. This review will provide important insights into rational design of new HED fuel with different ring-types/sizes and inspire the chemists to turn those literature studies into practical applications in military field.

关键词： Biomass-based chemicals Catalysis Cycloaddition Cycloalkanes High-energy-density fuel

Quantification of Central and Eastern China's atmospheric CH_(4) enhancement changes and its contributions based on machine learning approach

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Journal of Environmental Sciences 2024年第4期138卷 236-248页

作者： Xinyue Ai cheng hu Yanrong Yang Leying Zhang huili Liu Junqing Zhang Xin Chen Guoqiang Bai Wei Xiao College of Biology and the Environment Joint Center for sustainable Forestry in Southern ChinaNanjing Forestry UniversityNanjing 210037China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044China Guang’an Vocational&Technical College Guangan 638550China huaNan Meteorological Administration Huanan 154400China

Methane is the second largest anthropogenic greenhouse gas,and changes in atmospheric methane concentrations can reflect the dynamic balance between its emissions and sinks.Therefore,the monitoring of CH_(4) concentration changes and the assessment of underlying driving factors can provide scientific basis for the government’s policy making and evaluation.China is the world’s largest emitter of anthropogenic methane.However,due to the lack of ground-based observation sites,little work has been done on the spatial-temporal variations for the past decades and influencing factors in China,especially for areas with high anthropogenic emissions as Central and Eastern China.Here to quantify atmospheric CH_(4) enhancements trends and its driving factors in Central and Eastern China,we combined the most up-to-date TROPOMI satellite-based column CH_(4)(xCH_(4))concentration from 2018 to 2022,anthropogenic and natural emissions,and a random forest-based machine learning approach,to simulate atmospheric xCH_(4) enhancements from 2001 to 2018.The results showed that(1)the random forest model was able to accurately establish the relationship between emission sources and xCH_(4) enhancement with a correlation coefficient(R^(2))of 0.89 and a root mean-square error(RMSE)of 11.98 ppb;(2)The xCH_(4) enhancement only increased from 48.21±2.02 ppb to 49.79±1.87 ppb from the year of 2001 to 2018,with a relative change of 3.27%±0.13%;(3)The simulation results showed that the energy activities and waste treatment were the main contributors to the increase in xCH_(4) enhancement,contributing 68.00% and 31.21%,respectively,and the decrease of animal ruminants contributed-6.70% of its enhancement trend.

关键词： TROPOMI Methane column concentrations Anthropogenic sources Random Forest model

Biochar for future and futuristic biochar

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Pedosphere 2023年第5期33卷 680-682页

作者： hu cheng Yang SONG Nanthi BOLAN Co-Innovation Center for the Sustainable Forestry in Southern China College of Biology and the EnvironmentNanjing Forestry UniversityNanjing 210037China CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China School of Agriculture and Environment The University of Western AustraliaNedland WA-6009Australia The UWA Institute of Agriculture The University of Western AustraliaNedland WA-6009Australia Healthy Environments and Lives(HEAL)National Research Network Nedland WA-6009Australia

Biochar,a close-to-natural product derived from renewable biomass resources,has proven to be a promising carbon-negative material for achieving sustainable development goals and improving the future well-being of ecosystems and human life.Over the past thousands of years,advances in biochar research could generally be divided into three stages:the historical application stage,the recognition and investigation stage,and the rapid engineered development and advancement stage.In this perspective,we describe the development history of biochar,discuss the features of futuristic biochar,and propose new research directions for biochar in the future.

关键词： directions char ecosystems

“史蕴诗心”与“神话化历史”——兼论史学应有更高的思想和精神境界

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史林 2024年第2期 204-215,220页

作者：胡成南京大学历史学院 210033

“史蕴诗心”是钱锺书先生于1983年前后提出,然他自己却未深入展开讨论的一个话题。遗憾的是,40多年来,史学界对此的回应屈指可数。如果视之为一个对后人伟大的学术期盼,我们或可回溯到中、西史学演化的历史脉络之中,尝试探讨其心目中... 详细信息

“史蕴诗心”是钱锺书先生于1983年前后提出,然他自己却未深入展开讨论的一个话题。遗憾的是,40多年来,史学界对此的回应屈指可数。如果视之为一个对后人伟大的学术期盼,我们或可回溯到中、西史学演化的历史脉络之中,尝试探讨其心目中“诗”“史”关系、“诗心”的现代意涵,以及作为实现路径的“神话化历史”。由此我们还可推论:钱先生大致会认可史学还有更高的思想和精神境界,即不应止步于努力开掘意义上的历史“真相”、引人入胜的文字风采,最重要的是当矢志探求普适意义上能“将许多灵魂团结在一起”的“历史真理”。

关键词：钱锺书西方史学中国史学神话化历史历史真理

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行政协议案件司法审查标准的厘清与构建

法律适用 2024年第6期 35-51页

作者：程琥北京市第一中级人民法院

行政性与合同性是行政协议的双重属性,行政协议案件司法审查标准应当基于行政协议的双重属性进行构建。行政性是行政协议的基本属性,是行政协议的外部形式,决定了人民法院应当坚持合法性审查,对行政协议的外部形式进行形式合法性审查;... 详细信息

行政性与合同性是行政协议的双重属性,行政协议案件司法审查标准应当基于行政协议的双重属性进行构建。行政性是行政协议的基本属性,是行政协议的外部形式,决定了人民法院应当坚持合法性审查,对行政协议的外部形式进行形式合法性审查;合同性是行政协议的根本属性,是行政协议的内部形式,决定了人民法院应当坚持合约性审查,对行政协议内部形式进行实质合法性审查。形式合法性审查与实质合法性审查是辩证统一关系,在司法审查中不可或缺,共同构成行政协议案件司法审查标准。

关键词：行政协议司法审查标准形式合法性审查实质合法性审查

带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中的霍金辐射

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物理学报 2024年第2期73卷 104-111页

作者：韩亦文胡成洪云重庆工商大学物理系重庆400067 成都东软学院基础教学学院成都611844

本文研究了带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中出射粒子的量子隧穿辐射过程.其中,将宇宙学参数视为动态变量而不同于之前研究工作中将其视为常数而忽略其贡献.具体地,在计算出射粒子隧穿率时将宇宙学参数引入计算... 详细信息

本文研究了带有整体单极的Reissner-Nordstrom-AdS黑洞在扩展相空间中出射粒子的量子隧穿辐射过程.其中,将宇宙学参数视为动态变量而不同于之前研究工作中将其视为常数而忽略其贡献.具体地,在计算出射粒子隧穿率时将宇宙学参数引入计算并将其解释为热力学压强.计算结果表明,出射粒子的隧穿率与粒子出射前后黑洞的贝肯斯坦-霍金熵差成正比,辐射谱偏离了纯热谱,该结果与将宇宙学参数视为常数的情况完全相同.这意味着在扩展相空间中可以得到粒子的隧穿概率,并且隧穿过程不依赖于热力学状参量,这一工作自然地进一步将霍金辐射推广到了带有整体单极Reissner-Nordstrom-AdS黑洞扩展相空间中.结果表明,整体单极子尽管影响粒子的动力学行为和热力学量,但并不影响熵变和隧穿率.

关键词：霍金辐射宇宙学参数热力学压强整体单级

Quasi-static and low-velocity impact mechanical behaviors of entangled porous metallic wire material under different temperatures

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Defence Technology（防务技术） 2023年第1期19卷 143-152页

作者： Yi-wan Wu hu cheng Shang-zhou Li Yu Tang Hong-bai Bai Chun-hong Lu Engineering Research Center for Metal Rubber School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Department of Automotive Engineering Hebei College of Industry and TechnologyShijiazhuang050091China

To improve the defense capability of military equipment under extreme conditions,impact-resistant and high-energy-consuming materials have to be developed.The damping characteristic of entangled porous metallic wire materials(EPMWM)for vibration isolation was previously investigated.In this paper,a study focusing on the impact-resistance of EPMWM with the consideration of ambient temperature is presented.The quasi-static and low-velocity impact mechanical behavior of EPMWM under different temperatures(25℃-300℃)are systematically studied.The results of the static compression test show that the damping energy dissipation of EPMWM increases with temperature while the nonlinear damping characteristics are gradually enhanced.During the impact experiments,the impact energy loss rate of EPMWM was between 65%and 85%,while the temperatures increased from 25℃to 300℃.Moreover,under the same drop impact conditions,the overall deformation of EPMWM decreases in the temperature range of 100℃-200℃.On the other hand,the impact stiffness,energy dissipation,and impact loss factor of EPMWM significantly increase with temperature.This can be attributed to an increase in temperature,which changes the thermal expansion coefficient and contact state of the internal wire helixes.Consequently,the energy dissipation mode(dry friction,air damping,and plastic deformation)of EPMWM is also altered.Therefore,the EPMWM may act as a potential candidate material for superior energy absorption applications.

关键词： Entangled porous metallic wire material Low-velocity impact High temperature Energy dissipation characteristics Mechanical behavior

城市固废焚烧过程炉温与烟气含氧量多目标鲁棒预测模型

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自动化学报 2024年第5期50卷 1001-1014页

作者：胡开成严爱军汤健北京工业大学信息学部北京100124 数字社区教育部工程研究中心北京100124 城市轨道交通北京实验室北京100124

为实现城市固废焚烧(Municipal solid waste incineration,MSWI)过程炉温与烟气含氧量的准确预测,提出一种基于改进随机配置网络的多目标鲁棒建模方法(Multi-target robust modeling method based on improved stochastic configuration network,MRI-SCN).首先,设计了一种并行方式增量构建SCN隐含层,通过信息叠加与跨越连接来增强隐含层映射多样性,并利用参数自适应变化的监督不等式分配隐含层参数;其次,使用F范数与L_(2,1)范数正则项建立矩阵弹性网对模型参数进行稀疏约束,以建模炉温与烟气含氧量间的相关性;接着,采用混合拉普拉斯分布作为每个目标建模误差的先验分布,通过最大后验估计重新评估SCN模型的输出权值,以增强其鲁棒性;最后,利用城市固废焚烧过程的历史数据对所提建模方法的性能进行测试.实验结果表明,所提建模方法在预测精度与鲁棒性方面具有优势.

关键词：城市固废焚烧炉温烟气含氧量随机配置网络隐含层并行构造多目标鲁棒建模

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初中数学“情境-问题-思维”教学模式建构

教学与管理 2024年第1期 41-45页

作者：胡连成丰县梁寨镇梁寨初级中学江苏徐州221700

数学教学是指向思维发展的教学,而“情境-问题-思维”教学是实现这一旨归的重要路径:结合学生学习最近发展区,设计指向数学本质、兼具“真、趣、美、简”的问题情境,引发认知冲突,生成核心问题;基于相应数学思维的指导,通过问题变式形... 详细信息

数学教学是指向思维发展的教学,而“情境-问题-思维”教学是实现这一旨归的重要路径:结合学生学习最近发展区,设计指向数学本质、兼具“真、趣、美、简”的问题情境,引发认知冲突,生成核心问题;基于相应数学思维的指导,通过问题变式形成问题链,引领学生思维活动;通过思维定向、内化与外显等诸环节,在发展数学思维的同时实现一般性思维策略的提升。

关键词：情境设计问题变式问题链理性思维初中数学