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131.
132.
利用激光光散射技术,研究了不同条件下Ferton反应中Fe(Ⅲ)水解过程的粒径变化,并和一般铁盐体系中Fe(Ⅲ)水解过程进行了比较,结果表明,Fe(Ⅲ)的水解过程中,粒径变化受水解度B^*和铁盐浓度的影响,即B^*值愈大,浓度愈高,体系粒径愈大.并且在相同浓度和水解度B^*的条件下,Fenton反应生成的Fe(Ⅲ)比一般铁盐的水解聚合迅速,形成的粒径大,对采油废水进行处理的实验结果表明,Fenton体系对有机物的吸附去除效果明显优于常规铁盐体系,这可能与Fenton体系的高水解速率有关。 相似文献
133.
目的验证一种基于遗忘因子最小二乘法(FFRLS)的含能材料反应釜温度预测模型辨识方法的正确性和有效性。方法首先利用基于机理建模方法对系统模型进行分段处理,并得到其具体结构,然后结合历史数据,利用FFRLS对系统模型参数进行辨识,最后得到含能材料反应釜温度仿真模型。结果在Matlab仿真平台上对该方法的正确性和有效性进行验证,模型参数慢时变状态下该方法辨识参数的模型参数均方根误差(RMSE)皆小于10%,模型参数突变状态下,参数RMSE最小为5.89%,最大为18.69%。结论该方法能准确、有效地对含能材料反应釜温度模型进行辨识。 相似文献
134.
针对区域资源环境与社会经济系统的非连续运动特征,基于尖点突变理论构建数学模型对区域资源环境与社会经济系统的突变过程及其响应机制进行定量描述与分析。吉林省社会经济进入快速发展时期,以吉林省作为研究区域进行实例分析,能够为区域社会经济与资源环境协调发展战略的制定与筛选提供技术手段和决策依据。研究结果表明,吉林省经济进入快速增长阶段;矿业的衰退将成为影响吉林省经济持续稳定发展的重要因素;吉林省资源消耗总量与万元产值消耗量的突变,标志着吉林省对钢铁和水泥等大宗固体矿产的消费进入快速增长阶段;受生态省建设战略影响,固体废物、SO2、粉尘的排放总量与万元产值SO2及固体废弃物排放量发生根本性转变,吉林省生态环境进入新的发展时期。 相似文献
135.
30CrMnSiNi2A超强钢激光熔覆修复试验研究 总被引:3,自引:0,他引:3
目的研究激光熔覆技术,解决30CrMnSiNi2A钢制部件表面腐蚀、划伤、裂纹等缺陷的修复问题。方法利用光纤激光器在30CrMnSiNi2A钢表面进行同基体相近成分的合金粉末熔覆试验,优化激光熔覆工艺参数,开展熔覆层的微观组织、硬度、力学性能等方面试验研究,并对拉伸试样的断口进行分析。结果熔覆层与基体呈现牢固的冶金结合,基体热影响区域小,熔覆区的抗拉强度大于基体强度的80%,熔覆区材质的脆性较基材有所增加。结论激光熔覆可用于修复30CrMnSiNi2A钢制零件表面的腐蚀、划伤、裂纹等局部缺陷。 相似文献
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137.
Methane emissions from 3 different landfills inthe Netherlands were estimated using a mobileTuneable Diode Laser system (TDL). The methaneconcentration in the cross section of the plumeis measured downwind of the source on a transectperpendicular to the wind direction. A gaussianplume model was used to simulate theconcentration levels at the transect. Theemission from the source is calculated from themeasured and modelled concentration levels.Calibration of the plume dispersion model isdone using a tracer (N2O) that is releasedfrom the landfill and measured simultaneouslywith the TDL system. The emission estimates forthe different locations ranged from 3.6 to 16 m3 ha-1 hr-1 for the differentsites. The emission levels were compared toemission estimates based on the landfill gasproduction models. This comparison suggestsoxidation rates that are up to 50% in springand negligible in November. At one of the threesites measurements were performed in campaignsin 3 consecutive years. Comparison of theemission levels in the first and second yearshowed a reduction of the methane emission ofabout 50% due to implementation of a gasextraction system. From the second to the thirdyear emissions increased by a factor of 4 due tonew landfilling. Furthermore measurements wereperformed in winter when oxidation efficiencywas reduced. This paper describes themeasurement technique used, and discusses theresults of the experimental sessions that were performed. 相似文献
138.
Screening of flocculant-producing strains by NTG mutagenesis 总被引:4,自引:1,他引:3
Screening of new microorganism being able to produce efficiently flocculants was carried out. A new model for screening efficient flocculant-producing strains was designed and tested. The results showed that this model for screening efficient flocculant-producing strains is very reliable and can greatly shorten the screening period. 13 flocculant-producing strains were isolated from activated sludge by conventional method. A strain, designated as HHE6, produced the bioflocculant with the turbidity removal 98% for kaolin suspension. Six of 13 strains selected as the original strains were treated with NTG as mutagen, and five mutant strains(HHE-P7, HHE-A8, HHE-P21,HHE-P24, HHE-A26) with high flocculation efficiency was obtained by selection, which exhibited the flocculation rate for kaolin suspension above 90%. Strains HHE6, HHE-P7, and HHE-P24 were classified as Penicillium purpurogenum, HHE-P21 as Penicillium cyclopium,HHE-A26 as Aspergillus versicolor and HHE-A8 as Aspergillus fumigatus, and it is hitherto unreported for biofloccutant-producing strains of Penicillium. The growth of the six strains(HHE6, HHE-P7, HHE-A8, HHE-P21, HHE-P24, HHE-A26) had similar curves, i.e. firstly increasing rapidly, keeping relatively constant then and finally decreasing gradually with cultivation time. The production of bioflocculants by strains showed the similar pattern to strain growth. 相似文献
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140.