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驻波型热声制冷机熵产分析

工程热物理学报 2006年第3期27卷 508-510页

作者：孟繁孔李志信清华大学航天航空学院北京100084

声制冷机是一种新型制冷机,具有无机械运动部件,可靠性高寿命长,采用惰性气体为工质无污染等优点．驻波型热声制冷机的声功泵热效应是不可逆过程,内部不可逆损失导致热声制冷机效率偏低,制约了热声制冷机的发展和应用．本文研究了线性... 详细信息

声制冷机是一种新型制冷机,具有无机械运动部件,可靠性高寿命长,采用惰性气体为工质无污染等优点．驻波型热声制冷机的声功泵热效应是不可逆过程,内部不可逆损失导致热声制冷机效率偏低,制约了热声制冷机的发展和应用．本文研究了线性范围内驻波型制冷机换热器和回热器内的可压缩振荡流动与传热过程的熵产,分析了板间距,振荡频率和温度梯度对熵产的影响。

关键词：驻波型热声制冷机熵产振荡流换热器回热器

A study of water curtain parameters of underground oil storage caverns using time series monitoring and numerical simulation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第3期22卷 165-181页

作者： Yi-guo XUE Ze-xu NING Dao-hong QIU Mao-xin SU Zhi-qiang LI fan-meng kong Guang-kun LI Peng WANG Research Center of Geotechnical and Structural Engineering Shandong UniversityJinan 250061China

Water curtain systems(WCSs)are key components for the operation of underground oil storage caverns(UOSCs)and their optimization and design are important areas of *** on the time series monitoring of the first large-scale underground water-sealed storage cavern project in China,and on finite element analysis,this study explores the optimum design criteria for WCSs in water-sealed oil *** shows that the optimal hole spacing of the WCS for this underground storage cavern is 10 m in order to ensure seal *** the WCS is designed with a 10-m horizontal hole spacing and a water curtain pressure(WCP)of 80 kPa,a water curtain hole(WCH)has an influence radius of approximately 25 *** smaller the vertical distance is between a WCH and the main cavern,the greater the water inflow into the main *** vertical hydraulic gradient criterion can be satisfied when this distance is 25 *** shows that the optimal WCP is 70 kPa,which meets sealing requirements.

关键词： Underground oil storage Water curtain system(WCS) Water-sealed cavern Optimum design criteria Monitoring data Finite element method(FEM)

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一种航天器热平衡试验温度稳定判据确定方法

宇航学报 2016年第10期37卷 1263-1270页

作者：孟繁孔赵亮卿恒新范宇峰满广龙范含林北京空间飞行器总体设计部北京100094

针对典型航天器热控设计与传热过程特点,建立了设备与舱体动态耦合换热集总参数模型。提出了一种基于热时间常数的航天器热平衡试验温度稳定判据确定方法,给出了双节点耦合换热型航天器系统的热时间常数定义,建立了热平衡温差与温度变... 详细信息

针对典型航天器热控设计与传热过程特点,建立了设备与舱体动态耦合换热集总参数模型。提出了一种基于热时间常数的航天器热平衡试验温度稳定判据确定方法,给出了双节点耦合换热型航天器系统的热时间常数定义,建立了热平衡温差与温度变化率的对应关系。提出了基于Levenberg-Marquardt最小二乘法温度曲线拟合的热时间常数实时修正方法,该实时修正方法可用于多节点耦合换热航天器热平衡温度稳定判据确定。讨论了目前广泛采用的航天器热平衡试验温度稳定判据的适用性,研究结果可用于指导航天器热平衡试验中温度稳定判据确定。

关键词：热平衡试验温度稳定判据热时间常数热控

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一种基于机器视觉的纸病识别方法

中国造纸学报 2013年第1期28卷 48-52页

作者：张学兰李军孟范孔华南理工大学制浆造纸工程国家重点实验室广东广州510640 华南理工大学广东省造纸技术与装备公共实验室广东广州510640 华南理工大学机械与汽车工程学院广东广州510640

提出了一种基于图像灰度变换和BP神经网络的纸病识别算法。该算法是利用动态双阈值法和图像合成法对图像进行预处理,提取出纸病的特征值,再利用BP神经网络对纸病进行分类。结果表明,BP神经网络分类器可以很好地识别出纸病图像中的孔洞... 详细信息

提出了一种基于图像灰度变换和BP神经网络的纸病识别算法。该算法是利用动态双阈值法和图像合成法对图像进行预处理,提取出纸病的特征值,再利用BP神经网络对纸病进行分类。结果表明,BP神经网络分类器可以很好地识别出纸病图像中的孔洞、脏点和褶皱,平均识别率达93.8%。

关键词：纸病图像图像灰度特征值 BP神经网络

米氏凯伦藻多糖的酶法制备及其体外抑制肿瘤血管生成活性

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天然产物研究与开发 2016年第9期28卷 1470-1474,1442页

作者：陈宇婷孟繁桐孔亮田夕凡谭成玉大连海洋大学海洋科技与环境学院大连116023 天津德恒科技有限公司天津300384

研究碱性蛋白酶酶解制备米氏凯伦藻多糖及其抑制肿瘤血管活性。采用闪式萃取结合酶法制备米氏凯伦藻多糖,其适宜提取条件为碱性蛋白酶酶解温度40℃、酶解p H为8.5、酶用量为2.5%、酶解时间为2 h。其提取液经三氯乙酸除蛋白、乙醇沉淀获... 详细信息

研究碱性蛋白酶酶解制备米氏凯伦藻多糖及其抑制肿瘤血管活性。采用闪式萃取结合酶法制备米氏凯伦藻多糖,其适宜提取条件为碱性蛋白酶酶解温度40℃、酶解p H为8.5、酶用量为2.5%、酶解时间为2 h。其提取液经三氯乙酸除蛋白、乙醇沉淀获得米氏凯伦藻多糖。制备的米氏凯伦藻多糖在一定浓度时可抑制肿瘤细胞培养液诱导的内皮细胞增殖和迁移作用,具有一定的抑制肿瘤血管生成活性。

关键词：米氏凯伦藻多糖闪式萃取结合酶法抑制血管生成

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu Liu Shiji Da Lingbin kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

The School that Changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： GUO QING kong SIQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** Sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant Sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest

A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang Wei Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （SIBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for SIBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （<0.7 V） and excellent cyclic *** three-sodium storage mechanism was demonstrated with various in-situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for SIBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

Application of Muskingum routing method with variable parameters in ungauged basin

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Water Science and Engineering 2011年第1期4卷 1-12页

作者： Xiao-meng SONG fan-zhe kong Zhao-xia ZHU School of Resource and Earth Science China University of Mining and Technology Xuzhou 221116 P. R. China Graduate School China University of Mining and Technology Xuzhou 221008 P. R. China Department of Resources and Survey Engineering Chongqing Vocational Institute of Engineering Chongqing 400037 B R. China

This paper describes a flood routing method applied in an ungauged basin, utilizing the Muskingum model with variable parameters of wave travel time K and weight coefficient of discharge x based on the physical characteristics of the river reach and flood, including the reach slope, length, width, and flood discharge. Three formulas for estimating parameters of wide rectangular, triangular, and parabolic cross sections are proposed. The influence of the flood on channel flow routing parameters is taken into account. The HEC-HMS hydrological model and the geospatial hydrologic analysis module HEC-GeoHMS were used to extract channel or watershed characteristics and to divide sub-basins. In addition, the initial and constant-rate method, user synthetic unit hydrograph method, and exponential recession method were used to estimate runoff volumes, the direct runoff hydrograph, and the baseflow hydrograph, respectively. The Muskingum model with variable parameters was then applied in the Louzigou Basin in Henan Province of China, and of the results, the percentages of flood events with a relative error of peak discharge less than 20% and runoff volume less than 10% are both 100%. They also show that the percentages of flood events with coefficients of determination greater than 0.8 are 83.33%, 91.67%, and 87.5%, respectively, for rectangular, triangular, and parabolic cross sections in 24 flood events. Therefore, this method is applicable to ungauged basins.

关键词： Muskingum model," flood routing." variable parameters ungauged basin HEC-HMS