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Relationship between dew presence and Bassia dasyphylla plant growth

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Journal of Arid Land 2012年第1期4卷 11-18页

作者： YanLi ZHUANG Sophia RATCLIFFE Linze Inland River Basin Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Hydrology and Ecology Laboratory of Watershed Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Institute for Special Botany and Functional Biodiversity University of Leipzig

dew has been recognized for its ecological significance and has also been identified as an additional source of water in arid zones. We used factorial control experiment, under dew presence in the field, to explore photosynthetic performance, water status and growth response of desert annual herbage. Bassia dasyphylla seedlings were grown in contrasting dew treatments （dew-absent and dew-present） and different watering regimes （normal and deficient）. The effects of dew on the water status and photosynthetic performance of Bassia dasyphylla grown in a desert area of the Hexi Corridor in Northwestern China, were evaluated. The results indicated the pres- ence of dew significantly increased relative water content （RWC） of shoots and total biomass of plants in both water regimes, and enhanced the diurnal shoot water potential and stomatal conductance in the early morning, as well as photosynthetic rate, which reached its maximum only in the water-stressed regime. The presence of dew increased aboveground growth of plants and photosynthate accumulation in leaves, but decreased the root-to-shoot ratio in both water regimes. dew may have an important role in improving plant water status and ameliorating the adverse effects of plants exposed to prolonged drought.

关键词： dew Bassia dasyphylla water status photosynthesis performance biomass allocation pattern

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AN EXPERIMENTAL STUDY ON MEMBRANE DISTILLATION FOR TREATMENT OF GINSENG dew AND GINSENG WASHING WATER

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Chinese Science Bulletin 1989年第8期34卷 640-644页

作者：吴庸烈卫永弟刘静芝徐纪平 Changchun Institute oF Applied Chemistry Academia Sinica Bethune University of Medical Sciences Changchun

Membrane distillation is a new membrane separation process which has been developed in the last few years. When a piece of microporous hydrophobic membrane separates two kinds of aqueous solutions different in temperature, the solutions cannot transport through the pores of membrane in any directions because of the hydrophobicity of membrane. However, vapor can readily penetrate through

关键词： membrane distillation ginseng dew ginseng washing water.

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Differentiation of the Atmospheric Moisture Collected by dew and Fog

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Journal of Environmental Science and Engineering(A) 2016年第4期5卷 171-179页

作者： Esmaiel Malek Department of Applied Aviation Science Embry-Riddle Aeronautical University Daytona Beach FL 32114-390 USA

dew and fog play major roles in providing the atmospheric moisture for plants and arthropods living in arid regions all over the world. Studies are needed to discriminate between dew and fog. A radiation system was developed for measuring the incoming and outgoing solar （shortwave） radiation using two CM21 Kipp ＆ Zonen pyranometers （one inverted）, and the incoming （atmospheric） and outgoing （terrestrial） longwave radiation using two CG1 pyrgeometers in Logan （41047＇ N, 111~51＇ W, 1,460 m above mean sea level）, Utah, USA, continuously since 1995. These instruments are ventilated with heated air to prevent precipitation of dew and frost on the sensors, which otherwise would disturb the measurements. Based upon these measurements and an algorithm, the cloud base height, the cloud base temperature and percent of cloudiness can be parameterized at local scale. A cloud base height around zero would indicate fog at the local scale. In 1999, Bowen ratio system was added to measure the evapotranspiration, dew and frost continuously throughout the year at the same location close to the radiation system. Combining these two systems （radiation and Bowen ratio） has yielded a reasonable approach to differentiate between the atmospheric moistures collected by dew and fog.

关键词： dew fog short and longwave radiation.

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基于能量差比率的dew视频水印算法

计算机科学 2010年第5期37卷 271-273页

作者：孙文静南京审计学院南京210029 南京理工大学南京210094

提出了一种基于能量差比率的dew视频水印算法,该算法选择在I帧视频图像块能量(纹理)分布均匀的区域嵌入水印,每个I帧中嵌入的水印相同。实验结果证明,该算法水印鲁棒性好,码率稳定,检测可靠性高。

关键词：视频水印能量差比率 dew I帧

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Research on the Arrangement of dew Point Temperature Detectors of Capillary Plane Radiation Air-Conditioning

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Journal of Power and Energy Engineering 2014年第4期2卷 76-81页

作者： Xuelai Liu Jie Wu School of Thermal Energy Engineering Shandong Jianzhu University Jinan China

Based on analysis of the reason and process of condensation on ceiling radiant cooling panels, two kinds of arrangement of detectors are put forward. The physical model is established, the results show that detectors are arranged as the form of triangle is more suitable. It can not only satisfy the use requirement but also it is economical and practical. Finally we can conclude that the inlet water temperature 0.5°C higher than dew point temperature is safe and reliable.

关键词： Capillary Plane Radiation Air-Conditioning dew Point Temperature Detectors Arrangement

Evaluation of Cold dew Wind Monitoring Precision for Late Rice Based on CLDAS Data in Guangxi

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Agricultural Biotechnology 2019年第1期8卷 194-198页

作者： Yanli CHEN Yan HE Jianfei MO Yongming LUO Meihua DING Guangxi Institute of Meteorological Disaster Mitigation/Remote Sensing Application Test Base NSMC Guangxi Collaborative Innovation Center for Ecological Environment & Integrative Development in Xijiang River Basin

The low temperature process of cold dew wind( from September 19 to 27 in 2011) for late rice production was dynamically monitored by using CLDAS temperature,combined with the background information of rice cultivation from multi-source satellite database together with an reference to the monitoring indexes of cold dew wind disaster to verify the precision of CLDAS data,so as to provide a reference for monitoring chilling damage caused by cold dew wind in late rice production in Guangxi. The results showed that the cold wind dew caused heavy damage to an area of 3 159. 76 km^2,moderate damage to an area of 559. 77 km^2 and light damage to an area of 2 452. 14 km^2. The correlation coefficients between CLDAS inversion temperature and actual temperature of 12 verification meteorological stations were all larger than 0. 93,and the difference in daily average temperature was 0. 3 ℃. The time difference between maximum and minimum temperature provided by CLDAS and corresponding actual temperature from 12 meteorological stations was less than 1 h. The temperature data provided by CLDAS was in accordance with actual temperature data. With an advantage of rapidly,minutely and accurately monitoring the grade distribution of local cold dew wind disaster for late rice,CLDAS can be used in monitoring cold dew wind in late rice production in Guangxi.

关键词： Cold dew wind Late rice CLDAS Remote sensing Guangxi

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北极dew防线的秘密

环球军事 2004年第5期 50-53页

作者：彼德·格里尔,杨孝文美

四周一望无际的冰雪世界掩盖着一个已经过去了半个世纪的秘密:当年为了防止苏联入侵,美国和加拿大共同启动了有史以来最野心勃勃的建设项目之一——远程早期预警(Distant Early Warning)系统或称远程早期预警防线(dew Line)。美国《空... 详细信息

四周一望无际的冰雪世界掩盖着一个已经过去了半个世纪的秘密:当年为了防止苏联入侵,美国和加拿大共同启动了有史以来最野心勃勃的建设项目之一——远程早期预警(Distant Early Warning)系统或称远程早期预警防线(dew Line)。美国《空军》杂志2004年2月号刊登了彼德·格里尔(Peter Grier)的文章,揭开了这个鲜为人知的防御工程的神秘面纱。 50年前,位于北美洲气候恶劣的北极地区矗立着一部部雷达。50年后,这些远程预警雷达站仍旧矗立,只不过已经变得杂

关键词：美国空军 dew 加拿大雷达站

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战略导弹预警系统(dew)正在改进

系统工程与电子技术 1985年第12期 84-85页

作者：于丹峻崖

五十年代建成的从格陵兰一直延伸到加拿大北部的远程预警系统现正被北方预警系统计划所取代并得到很大改进。这个新的系统将从阿拉斯加横跨加拿大。已投资修建52个场地、包括13部由通用电气公司生产的操作人员极少的远程雷达和39部将由... 详细信息

五十年代建成的从格陵兰一直延伸到加拿大北部的远程预警系统现正被北方预警系统计划所取代并得到很大改进。这个新的系统将从阿拉斯加横跨加拿大。已投资修建52个场地、包括13部由通用电气公司生产的操作人员极少的远程雷达和39部将由斯佩里公司电子系统分公司提供的远程盲区弥补雷达。空军系统司令部电子系统分部与该公司就近程雷达于1984年8月签订了价值7970万美元为期42个月的合同。

关键词：斯佩里公司电子电气公司通用电气美元轻子本位币 dew 弹道导弹预警系统近程雷达警戒雷达无线电收发机美国空军控制组件

Application of Solar Energy for Recovery of Water from Atmospheric Air in Climatic Zones of Saudi Arabia

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Natural Resources 2011年第1期2卷 8-17页

作者： Ahmed M. Hamed Ayman A. Aly El-Shafei B. Zeidan Department of Mechanical Engineering Faculty of Engineering Taif University

In the present work, an investigation on the application of solar energy to heat a sandy bed impregnated with calcium chloride for recovery of water from atmospheric air is presented. The study also aimed at evaluating the effects of different parameters on the productivity of the system during regeneration. These parameters include system design characteristics and the climatic conditions. An experimental unit has been designed and installed for this purpose in climatic conditions of Taif area, Saudi Arabia. The experimental unit which has a surface area of 0.5 m2, comprises a solar/desiccant collector unit containing sandy bed impregnated with calcium chloride. The sandy layer impregnated with desiccant is subjected to ambient atmosphere to absorb water vapor in the night. During the sunshine period, the layer is covered with glass layer where desiccant is regenerated and water vapor is condensed on the glass surface. Ambient temperature, bed temperature and temperature of glass surface are recorded. Also, the productivity of the system has been evaluated. Desiccant concentration at start of regeneration is selected on the basis of the climatic data of Al-Hada region, which is located at Taif area, Saudi Arabia. Experimental measurements show that about 1.0 liter per m2 of pure water can be regenerated from the desiccant bed at the climatic conditions of Taif. Liquid desiccant with initial concentration of 30% can be regenerated to a final concentration of about 44%. Desiccant concentration at start of regeneration is selected on the basis of the climatic data of Al-Hada region. The climate of Taif city is dry compared with that for Al-Hada region. This method for extracting water from atmospheric air is more suitable for Al-Hada region especially in the fall and winter.

关键词： Extraction Atmospheric Air Absorption Liquid Desiccant Solar Energy dew Collection Regeneration