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以高温碱熔融处理粉煤灰合成了NaX型沸石分子筛,考察了不同水热晶化温度对产物结果的影响,用粉末XRD、XRF、SEM和FT-IR等手段对产品进行了表征,结果表明,以粉煤灰为原料用水热合成法合成微孔分子筛时,在晶化温度为90℃时能得到晶形较好的NaX型分子筛。同时考察了NaX分子筛的用量、时间和pH值等因素对Fe2+离子... 相似文献
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The important role of microwave receptors in bio-fuel production by microwave-induced pyrolysis of sewage sludge 总被引:1,自引:0,他引:1
Microwave receptor plays an important role in the microwave pyrolysis of sewage sludge in view of its significant influence on the yield and property of bio-fuel products. The yield and the chemical compositions of bio-fuels (gases and oils) obtained from sewage sludge mixed with different receptors (graphite, residue char, active carbon or silicon carbide) were investigated in this study by Gas Chromatography (GC), Gas Chromatography-Mass Spectrometry (GC-MS), and Fourier Transform Infrared Spectroscopy (FTIR). The results showed that the use of silicon carbide gave rise to the highest final temperature of 1130 °C, resulting in the highest yield of gas fraction (up to 63.2 wt.%). The low heating rate (200 °C/min) which was attributed to the addition of residue char promoted condensation reactions and resulted in an increase in solid yield. The existence of active carbon could prolong the resistance time of volatiles in the hot zone owing to its porous structure, generating the maximum concentration of H2 + CO (60%) in the pyrolysis gas. When graphite was used, the final low temperature favoured the cyclization of the alkenes, giving rise to a higher concentration of mononuclear aromatics in the pyrolysis oils. The model established in this study revealed that the quantity and quality of the products obtained from the microwave pyrolysis highly depended on the process conditions, which were influenced by the receptor significantly. 相似文献
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Yong Q. Tian Jianjun Wang John A. Duff Brian L. Howes Angeliki Evgenidou 《Environmental management》2009,44(1):119-135
This study examines the distribution, composition, and structure of benthic communities in nine shallow-water semienclosed
embayments on Cape Cod, southeastern Massachusetts. The spatial patterns were used to associate benthic characteristics with
local environmental factors. Field data from multiple years were collected to measure macrofaunal abundance, community composition,
and environmental characteristics. Multivariate statistics were used to analyze the spatial variations of species composition
and the abundance of benthic macrofauna. Canonical ordination, specifically redundancy analysis, was used to determine the
relative importance of the environmental factors (nutrients and habitat factors) being studied. The analyses demonstrate that
the benthic communities in the shallow tidal embayments are clearly clustered in association with the local environments.
Species composition and community structure of the benthic macrofauna are significantly correlated with water column parameters,
especially with phytoplankton biomass, total nitrogen, and dissolved oxygen. 相似文献
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安全生产工作创新之探索——"目视管理"在安全系统中的应用 总被引:1,自引:0,他引:1
根据事故统计资料分析,绝大部分事故都是由于员工违反操作规程引起的.对事故进行处理时往往发现企业有规章制度,但操作人员了解不够,认识不足,因此执行不力.规章制度的要求与现场执行存在很大的差距.如何使规章制度在现场得到有效执行,这是决定安全生产效果的关键. "目视管理"正是提高执行力的有效手段. 相似文献