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81.
通过对陶瓷墙地砖的坯釉原料、化学成份、生产工艺流程和产品的铅溶出量检测逐一分析研究,从理论和实践的结合上探讨了陶瓷墙地砖铅溶出量的问题。  相似文献   
82.
Today's news readers can be easily overwhelmed by the numerous news articles online. To cope with information overload, online news media publishes timelines for continuously developing news topics. However, the timeline summary does not show the relationship of storylines, and is not intuitive for readers to comprehend the development of a complex news topic. In this paper, we study a novel problem of exploring the interactions of storylines in a news topic. An interaction of two storylines is signified by informative news events that play a key role in both storylines. Storyline interactions can indicate key phases of a news topic, and reveal the latent connections among various aspects of the story. We address the coherence between news articles which is not considered in traditional similarity-based methods, and discover salient storyline interactions to form a clear, global picture of the news topic. User preference can be naturally integrated into our method to generate query-specific results. Comprehensive experiments on ten news topics show the effectiveness of our method over alternative approaches.  相似文献   
83.
84.
The possibility of using fly ash from municipal solid waste incineration (MSWI) in, for example, concrete is considered. MSWI fly ash, however, has too high a concentration of heavy metals, which may cause leaching problems during use or problems with waste handling at the end of the lifetime of the concrete. The Cl content in MSWI fly ash is also too high and will cause corrosion problems in reinforced concrete. The possibility of removing some of the unwanted heavy metals (Cu and Pb) together with Cl from an MSWI fly ash suspended in water using an electrodialytic separation method was investigated. The removal of Pb and Cu was found to be highly pH dependent and the highest contents removed were 41 and 90%, respectively. The Cu concentration of the ash decreased from 2200 to 860 mg kg?1 but the Pb concentration increased from 8560 to 16 800 mg kg?1, showing that Pb is mainly found in the ash fraction that is least soluble. Hence electrodialytic treatment of the ash suspended in water is not a solution to improve the ash quality in terms of Pb. The water‐soluble Cl content per unit weight of the original ash was 12.4%. The removal of water‐soluble Cl was efficient and >98% of Cl was removed (calculated on the basis of mean initial and final concentrations). This result indicates that electrodialytic extraction may be a method that can be used for the removal of Cl from ash prior to its utilization in concrete. Copyright © 2006 Society of Chemical Industry  相似文献   
85.
新型环氧防腐涂料的研究   总被引:1,自引:0,他引:1  
蒋春莲 《辽宁化工》2005,34(2):68-70
采用在环氧树脂中加入纳米复合铁钛粉防锈颜料WD—D-325、固化剂、制备了新型环氧树脂防腐涂料。由于纳米技术的特性,该防腐涂料具有较高的防腐性、优异的附着力和柔韧性。实验确定了复合铁钛粉防锈颜料在环氧防腐涂料中的添加量。作为新型的环保颜料,复合铁钛粉防锈颜料可以替代红丹、锌铬黄等颜料。  相似文献   
86.
The introduction of small quantities of lead into calcium hydroxyapatite catalysts produces marked increases in the selectivity to C2+ hydrocarbons, while the conversion of methane remains relatively constant. Small surface concentrations of lead are sufficient to achieve C2+ selectivities of 80 and 90%, with oxygen and nitrous oxide, respectively, in contrast with 18 and 46%, respectively, obtained in the absence of lead. Since surface concentration of lead species sufficient to stabilize pairs of methyl radicals in close proximity to each other would be expected to facilitate the formation of C2 hydrocarbons, an ensemble effect appears to be extant.  相似文献   
87.
余金保  李硕  姜明 《中国陶瓷》2003,39(5):70-71
用合成方法制备氧化铁覆膜滤沙。在动态条件下,研究了氧化铁覆膜滤沙对重金属离子Pb2 的吸附效果及吸附条件。含Pb2 的陶瓷化工厂废水经氧化铁覆膜滤沙吸附后,Pb2 离子含量显著低于国家排放标准。  相似文献   
88.
唐全胜  张永 《水泥工程》2006,(6):61-63,67
测温元件——热电偶热的电势大小仅和两金属的材料及两结合点的温度有关.鉴于此因素.适当的维护和维修可延长其使用寿命,减少生产成本。针对不同测量系统和不同工艺要求,介绍了四种水泥企业最常用的热电偶以及安装热电偶时所需注意事项。根据生产实践,重点介绍了热电偶的常见故障及其维护与维修方法。  相似文献   
89.
Thin films of PbTiO3 were deposited on fused silica, resistor-grade alumina, and single-crystal (100) MgO by a sol–gel processing method. Whereas the films deposited on silica and alumina substrates were randomly oriented and polycrystalline, highly {100} oriented PbTiO3 films were grown on the MgO single crystals. The perovskite-type structure was observed with films deposited on the single-crystal MgO and annealed at temperatures as low as 470°C, whereas a pyrochlore-type strcuture was observed with films on fused silica and alumina processed in a similar manner. All films heat-treated at temperatures in excess of 570°C showed significant formation of a second PbTi3O7 phase. The films were characterized by electron microscopy and glancing-incidence-angle X-ray diffraction.  相似文献   
90.
一种新型吸附剂在痕量重金属分析中的应用   总被引:2,自引:0,他引:2  
以二苯并18-冠-6交联席夫碱型壳聚糖作为新型吸附剂,用石墨炉原子吸收分光光度法测定了经过滤处理后的燃煤烟气中痕量铬、镉和铅的含量。经过滤处理后的燃煤烟气含铬1.42/μg/m3,其中三价铬占54.20%,为0.77μg/m3,镉0.256μg/m3,铅5.30μg/m3。  相似文献   
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