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791.
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7种粉煤灰样品的物理化学性质,如元素组成、结晶相组成、比表面积、灼失量、阳离子交换容量和pH得到表征。采用熔融法提取硅铝效率作为粉煤灰原料优选的依据,并通过L9(34)正交实验研究氢氧化钠投加量、熔融温度、氢氧化钠提取液浓度和体积对于硅铝提取效果的影响。结果表明,湿式除尘技术收集的低品位粉煤灰比电除尘技术所收集粉煤灰更... 相似文献
793.
Shouhai Li Chunpeng Wang Xiaowei Zhuang Yong Hu Fuxiang Chu 《Journal of Polymers and the Environment》2011,19(1):301-311
Renewable resource-based composites were prepared with acorn powder and Thermoplastic resin poly(lactic acid) (PLA) by twin-screw
extrusion followed by injection molding processing or hot-compression molding processing. The study of the composites microstructure
showed poor adhesion between acorn powder and PLA matrix. The hygroscopicity, mechanical properties and melt flow property
of composites were promising even though the composites had a 70 wt% content of acorn powder. Silane coupling agent, 4,4′-Methylenebis
(phenyl isocyanate) and PLA grafted with maleic anhydride did not show obvious effect on mechanical properties of composites.
The impact resistance strength of reinforced composites with steel fiber webs were improved greatly in comparison with those
having no steel fiber webs. Thermal properties results of DSC and DMA showed that the presence of acorn powder significantly
affected the crystallinity, crystallization temperature (Tc), glass transition temperature (Tg) and melting temperature (Tm) of PLA matrix. The study results proved that composites had superior mechanical properties, enough to partially replace
the conventional thermoplastic plastics. 相似文献
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796.
In-situ emission characteristics of odorous gases from two food waste processing plants 总被引:1,自引:0,他引:1
Jianguo Liu Xiaowei Wang Xiaoqin Nie Rundong Li Minying Song 《Journal of Material Cycles and Waste Management》2013,15(4):510-515
Odorous gas emission is the main environmental concern of food waste treatment. Two typical food waste processing plants, one for animal feed production by hydrothermal hydrolysis + aerobic fermentation (Plant A), and the other for biogas production by anaerobic digestion (Plant B), were selected to conduct in situ monitoring of fugitive odorous gas emission for five consecutive days, and the emission characteristics of NH3 and total volatile organic compounds (TVOC) were compared in this paper. The results showed that the two processes had different emission characteristics of odorous gases. Closed-operated hydrothermal hydrolysis had positive effects on overall fugitive odor control in plant A. Meanwhile, more fugitive odor gases may be released into the environment during the pretreatment with high-temperature and seemingly-open facilities in plant B. The emission strength of odor gases at night was generally lower than that in the day since more fresh food waste was received in the day and the higher temperature and lower air pressure in the day were favorable to gas emission. In general, the process of hydrothermal hydrolysis + aerobic fermentation was more advantageous in controlling odor than the process of anaerobic digestion. 相似文献
797.
Li X. Ni Kumud Acharya Xiang Y. Hao Shi Y. Li 《Journal of environmental science and health. Part. B》2013,48(2):153-161
Three common polyphenol compounds Gallic Acid (GA), Pyrogallic Acid (PA) and Catechol (CA) are known to have allelochemical-exhibiting inhibitory effects on the growth of the cyanobacterium Microcystis aeruginosa (M. aeruginosa). Metabolism and antioxidant responses in M. aeruginosa were investigated to elucidate the mechanism by which the three polyphenols inhibit algal growth. The inhibition effects of polyphenols were in the order of CA > PA > GA. The GA and CA exposures increased protein contents, superoxide dismutase (SOD) activity, catalase (CAT) activity and soluble sugar, especially for exposure to GA of 25 mg L?1. Soluble sugar content increased significantly especially when exposed to CA for 72 h. When exposed to PA, protein content, and SOD and CAT activities initially increased but over longer treatment time the activities decreased, in contrast to sugar content. Our results suggest that PA exposure for longer periods of time may inhibit catabolism action, while CA exposure could induce more oxide stress than GA or PA. The overall study showed that polyphenol-induced oxidative damage might be responsible for polyphenol inhibition on M. aeruginosa growth. The increases in cellular antioxidant enzymes and soluble sugar may have been to counteract the oxidative stress. 相似文献
798.
研究了非甾体抗炎药双氯芬酸的吸附去除过程与机制。对吸附处理效果较好的活性炭与纳米羟基氧化铁(α-FeOOH)进行了比表面积、Zeta电位等表面特性的表征,研究比较了双氯芬酸在活性炭与α—FeOOH2种材料上的吸附去除效果与吸附机制。结果表明,在相同的实验条件下,活性炭与α-FeOOH对双氯芬酸吸附去除率可分别达到97.9%和84.3%;双氯芬酸在活性炭上的吸附主要是由于活性炭较大的比表面积与疏水分配作用,在α-FeOOH上的吸附主要是由于静电引力作用;活性炭与α-FeOOH对双氯芬酸的吸附去除效果均随pH的升高而降低;在pH=6时,活性炭与α-FeOOH对双氯芬酸钠的吸附等温线均符合Langmuir方程,单位饱和吸附量分别为109.98mg/g和58.96mg/g;活性炭对双氯芬酸具有更强的吸附能力。 相似文献
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800.
采用以农业废弃物核桃壳为原料,天然软锰矿为添加剂共混制成的新型柱状活性炭进行了不同水蒸气含量下的烟气脱硫实验,利用Bangham和Elovich 2种模型对实验结果进行模拟与比较。实验结果表明,随着水蒸气含量的增加,穿透硫容和时间逐渐增加,并在水蒸气含量为10%时达到最大点,此时硫容为243.0 mg/g。模拟结果表明,2种模型均可以较好地模拟烟气脱硫实验结果,其中Elovich模型具有更高的拟合相关度和准确性。在对Elovich模型加以改进以包含水蒸气影响后,可以更好地描述烟气在不同水蒸气含量下的新型柱状活性炭脱硫情况。 相似文献