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121.
根据同时脱硫脱硝的要求,对以CuO为主要活性组分催化剂的制备过程和反应动力学进行了研究,通过实验获得浸清液浓度、浸渍时间,活化温度和活化时间等最佳制备条件,以及SO2和NOx脱除率达90%以上的反应温度、空间速度、CuSO4/CuO摩尔比和Cu/S比等工艺参数。 相似文献
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白阿魏侧耳(Pleurotus nebrodensis)是一种特有的食药两用珍稀真菌,具有调节人体生理平衡,增强人体免疫功能的作用。本文以白阿魏侧耳为材料,研究了不同的温度、pH值、碳源、氮源和通气条件对其菌丝生长影响。结果表明菌丝生长的适宜生长温度范围为22℃~30℃,最适温度是25℃;适宜生长pH值为5.0~8.0,最适pH值是7.5;最适碳源为蔗糖;最适氮源为蛋白胨;充足的氧气有利于菌丝生长。 相似文献
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介绍美国水土流失概况以及水土保持的发展阶段、措施、近期效益、投资变化、从业人员变化趋势和未来水土保持发展方向等。对照美国的情况,对我国水土流失和水土保持现状以及所处的发展阶段进行分析评价,提出了我国水土保持发展的建议和设想。 相似文献
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Competitive sorption between imidacloprid and imidacloprid-urea on soil clay minerals and humic acids 总被引:1,自引:0,他引:1
Soil organic matter and clay minerals are responsible for the adsorption of many pesticides. Adsorption and competitive sorption of imidacloprid on clay minerals and humic acids (HA) were determined using the batch equilibration method. The sorption coefficient of imidacloprid on humic acids was significantly higher than that on Ca-clay minerals, indicating that soil organic matter content was a more important property in influencing the adsorption of imidacloprid. Competitive sorption was investigated between imidacloprid and its main metabolite imidacloprid-urea on HA and Ca-clay minerals. The results showed that the sorption capacity of imidacloprid on clay minerals and HA was reduced in the presence of the metabolite, implying that imidacloprid-urea could occupy or block adsorption sites of imidacloprid on soil, potentially affecting the fate, transport, and bioavailability of imidacloprid in the environment. The interactions between a Ca-clay or HA-clay mixture and adsorption of imidacloprid and imidacloprid-urea were studied using IR differential spectra on thin films made of the adsorbent. The possible mechanisms were discussed from the shift of characteristic IR absorption bands of imidacloprid and imidacloprid-urea after sorption. 相似文献
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Accelerated Degradation of Methyl Isothiocyanate in Soil 总被引:1,自引:0,他引:1
Methyl isothiocyanate (MITC, CH3NCS) is the primary breakdown product of metam-sodium, and a potential replacement fumigant pesticide for methyl bromide. Methyl isothiocyanate is toxic and has a high potential for volatilization, therefore, minimizing its atmospheric emission is of the utmost importance. One method to reduce fumigant emissions is to enhance their degradation by incorporating organic amendments into the soil surface. In this study we determined the combined effect of temperature and chicken manure application rate on the degradation of MITC. The degradation of MITC was significantly accelerated by both increasing temperature and amendment rate. Differences between sterile and nonsterile degradation kinetics in unamended and organically amended soil indicate that MITC degradation is equally controlled by chemical and biological processes. The amelioration of soil with organic amendments should be further considered when designing fumigation practices that allow for reduced emissions. 相似文献