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Energy and Buildings

建筑节能 2019年第8期47卷 23-23页

作者：侯恩哲(摘录) 《建筑节能》

In this paper,the thermal performance of a rectangular latent heat storage unit(LHSU)coupled with a flat-plate solar collector was investigated numerically.The storage unit consists of a number of vertically oriented slabs of phase change material(PCM)exchanging heat with water acting as heat transfer fluid(HTF).During the day(charging mode),the water heated by the solar collector goes into the LHSU and transfers heat to the solid PCM which melts and hence stores latent thermal energy.The stored thermal energy is later transferred to the cold water during the night(discharging process)to produce useful hot water.The heat transfer process was modeled by developing a numerical model based on the finite volume approach and the conservation equations of mass,momentum,and energy.The developed numerical model was validated by comparing the simulation results,obtained by a self-developed code,with the experimental,numerical and theoretical results published in the literature.The numerical calculations were conducted for three commercial phase change materials having different melting points to find the optimum design of the LHSU for the meteorological conditions of a representative day of the month of July in Marrakesh city,Morocco.The design optimization study aims to determine the number of PCM slabs,water mass flow rate circulating in the solar collector and total mass of PCM that maximize the latent storage efficiency.The thermal performance of the LHSU and the flow characteristics were investigated during both charging and discharging processes.The results show that the amount of latent heat stored in the optimum design of the storage unit during the charging process is about 19.3 MJ,16.54 MJ,and 12.79 MJ for RT42,RT50,and RT60,respectively.The results also indicate that depending on the mass flow rate of HTF,the water outlet temperature during the discharging process varies within the temperature ranges 43.6℃-24℃,51.7℃-24℃,and 62.86℃-24℃for RT42,RT50,and RT60,respectively.

关键词： Phase change material(PCM) Latent heat storage unit(LHSU) Solar collector Heat transfer fluid(HTF) Melting Solidification

Estimation and Analysis of Green Land Variation Based on Similarity Theory

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Chinese Forestry Science and Technology 2012年第3期11卷 64-64页

作者： Wang Fang Wen Xiaorong Lin Guozhong She Guanghui College of Forest Resources and Environment Nanjing Forestry University

The similarity theory was systematically introduced,by combining the theory and the analytic hierarchy process(AHP),and taking the dynamic changes of two-stage green land patches in Shenzhen as an example,the patches similarity of each district and each green land type were estimated.The location,shape and areas of green land unit were used as the similarity elements.Then the similarity coefficients can be defined.The overlapping number of green land patches indicated the location variation of green land.The ratio of minimum and maximum shape index of green land indicated the shape variation of green land.With the same method,the areas variation coefficient was also obtained.The results shows that based on similarity theory and method the estimation of green land variation is feasible,which can provide effective methods and accordance for the further assessment of green land development in Shenzhen Special Economic Zone.

关键词： similarity theory green land patch dynamic change assessment Shenzhen

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Editor’s Note

International Understanding 2018年第4期 1-1页

作者： Xia Jiaoye 不详

The InterAction Council,in partnership with the Chinese Association for International Understanding,held its 35th Annual Plenary Meeting from September 28th to 30th,2018 in Beijing,China.Around 100 delegates,including the former state leaders and experts from over 20 countries,attended the Meeting and discussed issues of global governance,international trade,artificial intelligence and climate change etc.under the theme of “Global Governance:A Necessity for Our Times”.

关键词： nternational trade artificial intelligence climate change

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Preface

Chinese Journal of Chemical Engineering 2018年第11期26卷 I0003-I0003页

作者： GW Stevens Jinlong Gong The University of Melbourne Tianjin University

Climate change is perhaps the most important challenge facing the world today and case for limiting CO2 emission into the atmosphere now is compelling.Industrial emissions of CO2 are linked to the use of fossil fuels for energy,transport and material utilisation and is a key technical challenge for the immediate future.Both the Paris Accord and all of the road maps produced to achieve stable CO2 emissions,for example from the International Energy Association,show no one technology can produce the changes required in the time required and the range of technologies are necessary to meet the goal of CO2 stabilisation to limit temperature rise to less than 2℃.One key technology that all of these road maps rely on is carbon capture,utilisation and storage (CCUS).The reason for this is that in some areas other technologies,such as renewables cannot be deployed in time in all sectors,for example in aviation.The production of CO2 in many industrial applications,such as cement manufacture,are unavoidable and if the CO2 can be captured and reused or stored it offers a viable strategy to significantly reduce emissions,Carbon capture from bio sources to produce energy with the CO2 stored offers one of the few negative emission technologies available that is economic today.

关键词： Climate change Preface CO2

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英语词义变化的因素与类型（英文）

校园英语 2014年第29期 210-210页

作者：郭亚莉华中师范大学外国语学院

In general, the language has been divided into two classifications all over the world.One called dead language is the unpopular or out-of –date, another regarded as living language is still prevalent and mutative.The first part of the paper traces the history of English vocabulary integration, including the influence from politics and culture and the process of development and innovation, proving the integration of language is like the process of globalization.There is considerable evidence which has provided to show that any language, even English, will not be a state of fixation.Then, the author lists the types and factors of change with some examples in detail, so that explore further to have more accurate subdivision.The last part compares the features of Chinese and English to illustrate the continuous development and influence from other languages.

关键词： change English word meaning factors