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711.
用复合絮凝剂处理含乳化油废水的试验研究 总被引:11,自引:0,他引:11
本文对处理含乳化油废水所用的破乳絮凝剂进行了试验研究.分别采用电解质、无机高分子聚合物及电解质与高分子聚合物复合处理含乳化油废水.结果表明,与采用单一药剂相比,电解质与无机高分子聚合物复合处理含乳化油废水具有投药量小、药剂费用低、处理效果好、pH值适用范围宽等特点.本文还探讨了电解质与无机高分子聚合物复合破乳的机理,并且提出处理不同浓度的含乳化油废水时电解质与高分子聚合物的最佳复配比例及配比规律.还讨论了投加聚丙烯酰胺(PAM)的协同作用.这些为工业应用提供了必要的技术参数. 相似文献
712.
城市生活垃圾的堆肥研究 总被引:1,自引:0,他引:1
城市生活垃圾经动态式堆肥翻堆机处理制成腐熟堆肥,并最终试制成有机复混颗粒肥,二者先后在茶树、数种花卉作物和数种叶菜类蔬菜上进行田间试验,证明有较好的肥效,且成本较低廉,在农业生产上有实际应用的价值。从环境保护角度上看:这种方法是将城市生活垃圾转化为资源化、无害化的一项有意义的举措。 相似文献
713.
Summary. Qualitative and quantitative differences among pear cultivars were found
in constitutive and Cacopsylla-induced volatiles, depending on
experimental treatment of the trees (i.e., uninfested and partly or
completely infested by psyllids). Blend differences were also found
between pear cultivars and wild-type pear, alder and hawthorn–the
latter trees are frequently present in pear orchard
hedgerows. ?Interesting differences were found in the presence of methyl
salicylate and (E,E)-α-farnesene, two compounds previously found to
mediate attraction of predatory bugs towards psyllid-infested pear
trees. Methyl salicylate is expressed constitutively and is induced
systemically by infestation in the whole plant of all four cultivars.
(E,E)-α-farnesene on the other hand showed also systemic induction in
Bartlett, NY10355 and Beurré Hardy, but in partially infested Conference
trees it was induced locally, only in herbivore-damaged leaves. No
methyl salicylate or (E,E)-α-farnesene were identified in honeydew. In
field collected headspace samples of alder leaves infested by aphids and
leaf beetles we found methyl salicylate but no (E,E)-α-farnesene,
whereas in uninfested hawthorn neither were identified. Insight in the
variability of damage-related pear volatiles will have important
implications for integrated pest management in the field.
Received 27 August 2002; accepted 28 November 2002
R1D="
Correspondence to: Petru Scutareanu, e-mail:scuterea@science.uva.nl 相似文献
714.
为了减小传统本生灯火焰法测定层流预混火焰传播速度的误差,基于MATLAB图像处理技术提出了一种改进火焰图像处理及提取火焰边界线数据的方法。该方法对图像进行优化处理后运用LOG算子检测边缘信息,并为其添加平滑曲线;然后将散点拟合为函数表达式,选用Polynomial逼近方式修正拟合曲线误差;换算为实际坐标后对拟合函数进行面积积分计算,即得更接近真实的火焰外表面积。利用该方法对不同当量比下甲烷燃烧的本生灯火焰图像进行处理,求取其层流火焰传播速度,并与前人结果进行对比。结果表明,传统全面积法所得结果普遍偏高;相比于Vagelopulous利用平面火焰法所得结果,该方法获取的层流火焰传播速度在贫燃侧与之相近,在富燃侧则较之略低。 相似文献
715.
A novel microeconomic formalism for chemical processes is applied to air stripping of harmful volatile organic compounds (VOCs) from aqueous streams in a conventional packed tower. A simplified conceptual process model is combined with techno-economic aggregation rules to obtain an engineering production function, which relates process inputs (capital, material, labor, and energy) to output (stripped water flow rate). Process relationships determine column length and diameter required to achieve a specified VOC percent recovery from an aqueous stream of given composition and flow rate. Total capital is determined using a defined capital unit (1 capital unit=10 foot of 6-inch schedule 40 carbon steel welded pipe=$122, Jan. 1990) to put all installed capital equipment on the same basis and multiplying by 3.37 to account for the necessary plant infrastructure. Process labor is obtained from an empirical correlation, which relates workerhours to mass throughput. Simulations were made for four systems comprised from each of two representative random packings (i.e. 25-mm plastic Pall rings and 25-mm ceramic Raschig rings) and two model VOCs (i.e. 1,2-dichloroethane and trichloroethylene). Several examples are given, and process, technical and economic analyses of the results are presented. Two-dimensional (capital-energy) optimization was effective in determining the least cost combination of inputs for a plant to produce a specified output of stripped water. Furthermore, conventional economic models (e.g. Cobb-Douglas model) and associated methods (e.g. linear programming) were shown to be ineffective for air stripping plant design and optimization. Moreover, increasing returns to scale with economies of scale (declining long-run average cost) are prevalent. 相似文献
716.
用TOA-IBK系统革取,火焰原子吸收光谱法在同一条件下测定土壤、蔬菜中的铅镉.考察了TOA、KI、盐酸、抗坏血酸用量、革取时间、放置时间及在同等实验条件下钙、镁、铁等金属离子和酸的用量的干扰影响情况. 相似文献
717.
VW - 0 2 2 7-B型空压机的噪声源 ,其空气动力性噪声最强。拟在空压机进气口安装阻抗复合消声器 ,本文针对由最优化设计方法获得的阻抗复合型消声器模型 ,在未对消声器实物加工之前 ,根据消声器的图纸及有关数据进行了有限元动力计算 ,从而初步了解消声器的动态特性。由此可避免消声器制造的盲目性及重复实验 ,为设计优良消声器提供新的有效途径。 相似文献
718.
Eh-pH图是研究成矿溶液的重要手段之一。在传统元素-水体系的Eh—pH图的基础上,笔者提出和研究了成矿溶液中配合物体系的Eh-pH图的建立方法,为成矿溶液的理论模拟和成矿作用的研究提供了新的途径。 相似文献
719.
Wei Gao Xiaolong Tang Honghong Yi Shanxue Jiang Qingjun Yu Xizhou Xie Ruijie Zhuang 《环境科学学报(英文版)》2023,35(3):112-134
As the main contributor of the formation of particulate matter as well as ozone, volatile organic compounds(VOCs) greatly affect human health and the environmental quality. Catalytic combustion/oxidation has been viewed as an efficient, economically feasible and environmentally friendly way for the elimination of VOCs. Supported metal catalyst is the preferred type of catalysts applied for VOCs catalytic combustion because of the synergy between active components and support as well as its flexi... 相似文献
720.
通过对锥形件产品的研制 ,论证了采用复合挤压、变薄拉伸和扩锥挤压相结合的工艺方法是加工深孔薄壁锥形件的可靠工艺方法 ,得出了变薄拉伸加工中加工率不应处于临界加工率状态的结论。 相似文献