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981.
982.
This paper presents a new maritime lifesaving multiple-effect solar still design where several extended wicks feed seawater to their evaporating areas by capillary force, and the resulting water vapor diffuses and condenses on facing wicks with the condensate flowing through the wicks into storage bags. A theoretical analysis showed that a temperature drop through diffusion layers between evaporating and condensing wicks slowly increases in the main evaporating areas and rapidly near salt depositions whereas the evaporation rate decreases slowly in the main area and rapidly near salt depositions. These changes are caused by increases in salt concentrations and resulting boiling point elevation. With steady-state transfer analysis, the proposed still is predicted to produce about 15 kg m −2d−1 fresh water on a sunny day of 22 MJm−2d−1 solar radiation, showing a potential to be a maritime lifesaving desalinator. 相似文献
983.
The thermal properties of amorphous gelatin films and gelatin films with renatured structural order were measured by using conventional and temperature modulated differential scanning calorimetry (DSC). Different amounts of gelatin structural order associated with a melting enthalpic change in the DSC measurement were prepared based on different gelatin drying conditions. Two consecutive heating and cooling DSC measurements on the gelatin films showed that there was no change in the glass‐transition temperature (Tg) for the amorphous gelatin but there was a decrease in the Tg for the structural gelatin on the second DSC scan. This decrease was attributed to the plasticizing effect from the release of originally hydrogen‐bonded water associated with the structural gelatin. In addition, a reversing endotherm observed upon melting of the structural gelatin during a temperature modulated DSC measurement indicated that the transition of bound water to free water occurred as the partial triple‐helix gelatin melted. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1795–1801, 2006 相似文献
984.
Environmental concerns have stimulated interest in utilizing plant-derived materials in various industrial fields. The main objective of the present study was to synthesize a new type of high-performance lignin series dispersant of coal–water slurry (CWS) from wheat straw alkali lignin (WAL), and determine the affecting factors in the reaction and the application performance for CWS preparation. The experimental results showed that the inherent viscosity and the sulfonic group content of the modified wheat straw alkali lignin (MSL) are the key factors affecting its dispersing effect for CWS. In the reaction, the reactant mass concentration and the sulfonating agent amount were changed to obtain the MSL with different inherent viscosities and sulfonic group contents, and the MSL with intermediate inherent viscosity (6.0 ml/g) and higher sulfonic group content (1.80 mmol g− 1) was found to have excellent dispersing effect for CWS. The MSL obtained from optimized process was used as dispersant for CWS preparation, the studies of the properties of CWS showed that MSL has similar dispersing effect with naphtalenesulfonate–formaldehyde condensate, and far better dispersing effect than lignosulphonate. Recently this kind of new dispersant has been applied in several power plants in China. 相似文献
985.
侯纪蓉 《精细与专用化学品》1999,(20)
由于我国染料及中间体行业近三十年来发展迅猛,而染料企业大多数是小型厂,染料品种繁多,在化工系统中,这一行业目前几乎是污染最严重、污染面最大、治理最差的。同时,一些发达国家把污染重、难治理的产品关停,转向发展中国家生产,染料中间体便是其中之一。所以我国大量的小型乡镇企业治理难度就更大了。不同染料生产原料、工艺过程不同,所排“三废”即有共同的特性,又有各自特点,因此需要针对各自的不同分别处理。本文从废气、有机废液和废渣、废水三方面详细叙述了工业上常用的治理方法及适用条件。并例举了几类排放量较大的废水的治理方法。 相似文献
986.
Evgeny Shustorovich 《Catalysis Letters》1990,7(1-4):107-118
We have applied the BOC-MP method to theoretically analyze the metal effects in the Fischer-Tropsch (FT) synthesis by calculating the energetics of conceivable elementary steps (the relevant heats of chemisorption and the reaction activation barriers) during CO hydrogenation over the periodic series Fe(110), Ni(111), Pt(111), Cu(111). The basic steps such as dissociation of CO, hydrogenation of carbidic carbon, C-C chain growth by insertion of CH2 versus CO into the metal-alkyl bonds, and chain termination leading to hydrocarbons (alkanes versus -olefins) or oxygenates are discussed in detail. It is shown that the periodic trends in the ability of metal surfaces to dissociate chemical bonds and those to recombine the bonds are always opposite. In particular, we argue that metallic Fe is necessary to produce the abundance of carbidic carbon from CO but the synthesis of hydrocarbons and oxygenates can effectively proceed only on carbided Fe surfaces which resemble the less active metals such as Pt. More specifically, we project that the C-C chain growth should occur predominantly via CH2 insertion into the metal-alkyl bond and the primary FT products should be -olefins. These and other model projections are in agreement with experiment. 相似文献
987.
良庄煤矿在发展煤炭加工与综合利用方面探索了一些有效途径 ,在洗选加工方面采用重介选煤工艺代替跳汰选 ,运行效果良好 ,利用浮选精煤制备水煤浆及燃煤锅炉改烧水煤浆、压滤煤泥发电及矸石制砖等方面均有显著的经济和环保效益 相似文献
988.
邓雯雯 《数码设计:surface》2014,(7):57-58
水在自然界中,是重要的存在物质之一,也是人与自然之间互相联系的纽带。而水景元素,是现代景观设计中非常重要的组成,也是最富有表现魅力的艺术形式。水景元素在景观设计中的运用是十分广泛的,而且水具有很强的灵活性,变化形式丰富多样,在现代景观设计中是不可缺少的一部分。加强对于水景元素在现代景观设计中的研究与探讨,能够更好的促进现代景观设计的水平,催生出更多优秀的景观设计作品。文章介绍了景观设计中水景元素的一般类型以及特征,并阐述了水景元素在景观设计中的具体运用,以便在以后的景观设计中,更好的优化水景元素的设计。 相似文献
989.
智能水滴算法研究 总被引:1,自引:0,他引:1
马竹根 《计算机与数字工程》2014,(6):964-968
智能水滴算法是模拟自然界中河水与周围环境相互作用的过程而提出的一种智能计算方法。文章首先描述智能水滴算法的原理,然后综述智能水滴算法在多个研究领域的应用,最后对智能水滴算法进行总结与讨论。 相似文献
990.
n维的立方体将生成2n个聚集立方体.如何进行立方体计算,在存储空间和查询时间方面寻求平衡,成为多维分析应用中的关键问题.基于部分物化的策略,并结合水利普查数据特征,改进Minimal cubing方法,提出了层次维编码片段方法HDEF cubing.该方法利用编码长度较小的层次维编码及其前缀,快速检索出与查询关键字相匹配的层次维编码,减少了多表连接操作,从而提高查询效率.以水利普查数据为例,验证了改进的立方体计算方法能高效地对立方体进行存储和查询,适用于水利普查成果分析. 相似文献