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Experimental Study on the Condensation of a Thermosyphon by Electrical Capacitance Tomography

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Journal of Thermal Science 2016年第2期25卷 171-177页

作者： HAN Zhenxing mu huaiping LEI Jing ZHANG Jingyin LI Zhihong LIU Shi School of Energy Power and Mechanical Engineering North China Electric Power University

The study on the condensation and the two-phase flow pattern in the condensation section is important to understand the operating mechanisms in a thermosyphon. In this paper, a new electric capacitance tomography(ECT) sensor was designed for the visualization measurement in a liquid by removing the shielding case and sealing with insulating hydrophobic material. It was successfully used to measure the condensation process in a thermosyphon under different operating temperatures. The thermosyphon was made of silica glass, and alcohol was used as a working fluid. The alcohol vapor was cooled to condense through the heat convection with the cooling water. The operating temperature was controlled by a heater with different power outputs. The experimental results show that the alcohol vapor condensed in stripes and unevenly on the wall surface at a low operating temperature. The liquid bridge will be formed periodically at the operating temperature of 90?C, and the time interval between two liquid bridges will be shorter with the increase of the operating temperature. At 117?C or even higher operating temperatures, the complete liquid bridge cannot be formed sometimes due to the difference of the growth rate of the surface wave around the circumference.

关键词： Thermosyphon Condensation ECT Visualization

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基于高斯过程回归方法两相对流换热系数预测

华北电力大学学报（自然科学版） 2017年第2期44卷 97-104页

作者：任婷刘厦孙杨穆怀萍刘石华北电力大学能源动力与机械工程学院北京102206 华北电力大学控制与计算机工程学院北京102206

两相流经常发生在换热器中,其中气液两相流的换热特性在换热器的结构设计、材料选择和优化运行上起到了至关重要的作用。因此,在实际应用中需要获得两相对流换热系数。不同于常规的实验研究和数值计算方法,提出了一种利用实验数据和高... 详细信息

两相流经常发生在换热器中,其中气液两相流的换热特性在换热器的结构设计、材料选择和优化运行上起到了至关重要的作用。因此,在实际应用中需要获得两相对流换热系数。不同于常规的实验研究和数值计算方法,提出了一种利用实验数据和高斯过程回归(Gaussian Process Regression,GPR)相结合的方法快速预测两相对流换热系数。与其它方法的比较结果表明,GPR方法的预测精度高,预测结果与实验数据吻合较好;而且,该方法有利于减少实验次数和实验成本,节省原材料以及缩短设计周期,从而为研究气液两相流的换热特性提供一种有效方法。

关键词：气液两相流预测方法高斯过程回归

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硅醚-有机铝体系引发氧化环己烯光开环聚合

高分子学报 1989年第6期 728-730页

作者：曹维孝穆怀萍张骊冯新德北京大学化学系

环氧化合物的光开环聚合一般采用正离子光引发剂,常用的有重氮盐、硫鎓盐和碘鎓盐。它们在光照下产生Lewis酸引发环氧化合物开环聚合,由于Lewis酸对金属有强的腐蚀性,从而限制了它们在光固化涂料的应用。近年,Hayase等报道了一种新型... 详细信息

环氧化合物的光开环聚合一般采用正离子光引发剂,常用的有重氮盐、硫鎓盐和碘鎓盐。它们在光照下产生Lewis酸引发环氧化合物开环聚合,由于Lewis酸对金属有强的腐蚀性,从而限制了它们在光固化涂料的应用。近年,Hayase等报道了一种新型光引发剂,是由硅醚和有机铝组成。

关键词：氧化环己烷开环聚合光分解氧化环己烯光引发剂硅醚有机铝化合物

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皮肤毛发平滑肌瘤一例

中华皮肤科杂志 2001年第5期34卷 369-369页

作者：王红穆怀萍岳晓玉刘维达曾学思中国医学科学院中国协和医科大学皮肤病研究所南京210042 天津中医学院第一附属医院

X患者女， 28岁， 2000年 9月初诊。上胸部起小疙瘩 4年，部分伴触压痛 2年。 4年前，患者上胸部被蚊虫叮咬后，自觉瘙痒剧烈，搔抓后出现小红疙瘩，并逐渐增多成片。 2年后部分疙瘩出现触压痛，背部、左上臂及左小腿伸侧相继出现同样... 详细信息

X患者女， 28岁， 2000年 9月初诊。上胸部起小疙瘩 4年，部分伴触压痛 2年。 4年前，患者上胸部被蚊虫叮咬后，自觉瘙痒剧烈，搔抓后出现小红疙瘩，并逐渐增多成片。 2年后部分疙瘩出现触压痛，背部、左上臂及左小腿伸侧相继出现同样皮疹， 1年左右也出现触压痛，遇冷疼痛加剧。未经治疗。

关键词：皮肤肿瘤毛发平滑肌瘤病例报告

Dynamic Mechanical Properties and Energy Dissipation Characteristics of Frozen Soil Under Passive Confined Pressure

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Acta Mechanica Solida Sinica 2021年第2期34卷 184-203页

作者： Jinxuan Jia huaiping Tang Huijian Chen Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

Impact compression tests on frozen soil samples with different freezing temperatures and subjected to passive confined pressure were performed using a split Hopkinson pressure bar at different loading strain *** three-dimensional stress-strain curves of the frozen soil samples under the corresponding conditions were *** experimental results showed that,when the frozen soil was loaded to its elastic limit,shear failure occurred,the bearing capacity of pore ice was lost,and the thawed soil functioned as the main stress-bearing ***,the capacity of frozen soil to withstand hydrostatic pressure continued to *** dynamic mechanical properties of the frozen soil under passive confined pressure were observed to be strongly related to the loading strain rate and freezing *** the loading strain rate increased,the secant modulus,elastic modulus,and strength(including the shear strength)of the frozen soil increased,whereas its Poisson^ratio and coefficient of lateral pressure *** the freezing temperature decreased,the secant modulus,elastic modulus,and shear strength of the frozen soil increased;however,its Poisson5s ratio and coefficient of lateral pressure *** the frozen soil was subjected to impact loading under passive confined pressure,energy dissipation occurred due to plastic deformation,mesoscopic damage evolution,and ice-water phase *** shear failure occurred,the absorption energy per unit volume of frozen soil increased as the freezing temperature decreased and the loading strain rate increased.

关键词： Frozen soil Split Hopkinson pressure bar Passive confined pressure Dynamic mechanical properties Energy dissipation

The transmission of dengue virus with Aedes aegypti mosquito in a heterogeneous environment

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International Journal of Biomathematics 2021年第5期14卷 31-49页

作者： Mengyun Zhang Zhigui Lin huaiping Zhu School of Applied Mathematics Nanjing University of Finance&EconomicsNanjing 210003P.R.China School of Mathematical Science Yangzhou University Yangzhou 225002P.R.China Laboratory of Mathematical Parallel Systems(LAMPS)Department of Mathematics and Statistics York University TorontoONM3J 1P3Canada

This paper deals with dengue virus transmitted by the mosquito Aedes aegypti.A reaction-diffusion model is proposed incorporating both human and the *** population,where we divided mosquitoes into two sub-populations:the winged population and an aquatic form,with the winged mosquito population divided into the susceptible and infected *** threshold Qo depending on spatial heterogeneity is introduced for the mosquito ***,we introduce the basic reproduction number Rq for the infected classes,as well as its analytical *** and Ho are utilized to investigate the stability of the mosquito-established *** results show that the mosquitoes persist if Qo>1,while the transmission of dengue virus depends on the condition whether Ho1.

关键词： Reaction-diffusion model dengue virus Aedes aegypti mosquito basic reproduction number stability

Effects of phenanthrene on hepatic enzymatic activities in tilapia(Oreochromis niloticus ♀×*** ♂)

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Journal of Environmental Sciences 2009年第6期21卷 854-857页

作者： XU Wenju LI Yuanyou WU Qingyang WANG Shuqi ZHENG huaiping LIU Wenhua Marine Biology Institute of Shantou University Shantou Guangdong 515063 China Biology Department of Hanshan Normal University Chaozhou 521041 China

The effects of phenanthrene（Phe） on hepatosomatic index（HSI） and hepatic enzymatic activities in hybrid tilapia（Oreochromis niloticus ♀× *** ♂） were investigated via the static freshwater exposure at dosage of 50,100,and 400 μg/L for 4-14 *** with the control group,HSI was significantly decreased（P 〈 0.05） at 400 μg/L at day *** enzymatic activities（P 〈 0.05） were observed for catalase（CAT）,glutathione peroxidase（GPx） and superoxide dismutase（SOD） at either 100 or 400 μg/L at day 8 and 14,as well as for CAT at 50 μg/L at day 14,except for GPx at 400 μg/L at day *** O-deethylase（EROD） activity was significantly increased（P 〈 0.05） at all dosage at day 4 as well as at 50 μg/L at day 8,but significantly decreased at either 100 or 400 μg/L at day 14（P 〈 0.05）.Glutathione-S-transferase（GST） activity was not *** results suggest that CAT,GPx,SOD and EROD,as well as HSI in tilapia may be used as the biomarkers or indexes for evaluating or monitoring the pollution of polycyclic aromatic hydrocarbons（PAHs） such as Phe.

关键词： phenanthrene hepatic enzyme biomarker hybrid tilapia ( Oreochromis niloticus ♀×O.aureus ♂ )

Survey of the research on dynamic weapon-target assignment problem

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Journal of Systems Engineering and Electronics 2006年第3期17卷 559-565页

作者： Cai huaiping Liu Jingxu Chen Yingwu Wang Hao School of Information System & Management National Univ. of Defense TechnologyChangsha 410073 P. R. China

The basic concepts and models of weapon-target assignment （WTA） are introduced and the mathematical nature of the WTA models is also analyzed. A systematic survey of research on WTA problem is provided. The present research on WTA is focused on models and algorithms. In the research on models of WTA, the static WTA models are mainly studied and the dynamic WTA models are not fully studied in deed. In the research on algorithms of WTA, the intelligent algorithms are often used to solve the WTA problem. The small scale of static WTA problems has been solved very well, however, the large scale of dynamic WTA problems has not been solved effectively so far. Finally, the characteristics of dynamic WTA are analyzed and directions for the future research on dynamic WTA are discussed.

关键词： military operational research dynamic weapon-target assignment survey firepower assignment decision making combination optimization.

Analysis of a stochastic model for algal bloom with nutrient recycling

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International Journal of Biomathematics 2016年第6期9卷 59-85页

作者： Xuehui Ji Sanling Yuan huaiping Zhu School of ManagementUniversity of Shanghai for Science and Technology Shanghai 200093 P. R. China College of ScienceUniversity of Shanghai for Science and Technology Shanghai 200093 P. R. China Department of Mathematics and StatisticsYork University Toronto M3J 1P3 Canada

In this paper, the dynamics of a stochastic model for algal bloom with nutrient recy- cling is investigated. The model incorporates a white noise term in the growth equation of algae population to describe the effects of random fluctuations in the environment, and a nutrient recycling term in the nutrient equation to account for the conversion of detritus into nutrient. The existence and uniqueness of the global positive solution of the model is first proved. Then we study the long-time behavior of the model. Conditions for the extinction and persistence in the mean of the algae population are established. By using the theory of integral Markov semigroups, we show that the model has an invari- ant and asymptotically stable density. Numerical simulations illustrate our theoretical results.

关键词： Stochastic nutrient-algae model ItS's formula stochastic stability integralMarkov semigroup stationary distribution.