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361.
硫铁矿烧渣综合利用研究进展   总被引:14,自引:0,他引:14  
分析了硫铁矿渣的化学成分和酸浸还原提铁的基本原理。阐述了 硫铁矿烧渣湿法制备铁系产品的原理和途径,为硫铁矿烧渣的综合利用提供了一条有效途径。  相似文献   
362.
王岩  翟滨  王少君 《化工环保》2003,23(3):153-156
用酚渣油为原料,模拟酚醛树脂合成方法,对酚渣油的催化交联、松香改性等化学过程进行了研究,合成出性能良好、可用于制备涂料与胶粘剂的酚渣油树脂。试验结果表明,依照该工艺生产的酚渣油树脂,其主要技术指标达到制备涂料用酚醛树脂的标准,用酚渣油制备的涂料和胶粘剂的性能优于酚醛树脂。  相似文献   
363.
高岭土制备聚合氯化铝新工艺   总被引:6,自引:0,他引:6  
介绍了以高岭土为原料,经盐酸预处理后,加水聚合、调整反应液pH,制备液体聚合氯化铝净水剂的新工艺。对所得产品的净水性能和技术指标进行了测定,结果表明,采用该工艺制得的聚合氯化铝产品技术指标符合GB1592-95标准。  相似文献   
364.
相对于犯罪构成的完成形态即犯罪既遂,犯罪预备、犯罪未遂和犯罪中止是犯罪构成的未完成形态。本文阐述了犯罪构成的三种未完成形态的内容、意义和处罚原则,同时着重分析了它们之间的区别。  相似文献   
365.
针对当前突发事件应急演练存在的策划方面尚无统一标准、组织实施缺失执行规范等问题,在综合考察国内外演练设计相关成果基础上,从应急处置实际出发提出以突发事件情景构建、“责任人—资源—措施—事故应对”匹配、演练其他相关问题为要点的突发生产事故应急演练准备模式,并借助石化企业二甲苯泄漏模拟处置实例建立了以桌面推演、模拟测试及过程评估为核心的突发生产事故应急演练实施方法。廓清了突发生产事故应急演练的思路、方法和步骤,对企业组织开展应急演练和有效处置突发事件具有重要借鉴价值。  相似文献   
366.
以甲基丙烯酸缩水甘油酯为单体,利用单体聚合法制备了介孔型磁性离子交换树脂(m-MIER),并在表征其基本性状的基础上,初步分析了其对典型藻源含氮有机物(藻蓝蛋白、氨基酸)的去除效能.为便于比较,研究过程中同步进行了磁性离子交换树脂(MIEX®)的研究.研究结果表明,m-MIER是以氯为交换基团的介孔型材料,其孔径为2~60nm;与MIEX®相比,m-MIER具有相似的湿视密度、粒径,更丰富的孔隙结构、更大的交换容量(1.15g/cm3, 150~200 μm, 0.1852cm3/g, 3.16mmol/g Vs 1.20g/cm3, 150~180 μm, 0.0184cm3/g, 2.23mmol/g);XPS图谱分析结果表明其内核成分主要为Fe3O4,且为季胺型阴离子交换树脂.针对藻源含氮有机物的去除结果表明,m-MIER对藻蓝蛋白、特定氨基酸的去除效果明显优于MIEX®,且去除效果与氨基酸的种类显著相关.  相似文献   
367.
含硼聚硅酸硫酸铁锌复合絮凝剂的制备及性能   总被引:6,自引:0,他引:6  
制备了含硼聚硅酸硫酸铁锌复合絮凝剂(PSFZB),研究了硅酸钠溶液浓度、硅酸聚合时间、Fe/Si、Zn/Si、B/Si等因素对絮凝效果的影响,通过正交试验确定最佳制备工艺条件。试验结果表明,研制的PSFZB絮凝剂具有很好的稳定性和较佳的处理效果,适用的pH范围广,是一种较PAC、PFC优良的絮凝剂。  相似文献   
368.
Chemical hydrography, nutrients and trace metals in water, sediments and marine organisms were studied in the Bay of Mali Ston and their role in terms of pollution discussed. Results show that the entire study area is very strongly affected by the adjacent land. The overall area is well aerated so that no dangerous accumulation of nutrients with oxygen content reduction was recorded.

Results of analyses of trace metals show that the water and sediments of the bay contain high levels of some metals significantly higher than those from the open sea. This may be attributed to the natural sedimentation processes and the Neretva River and submarine spring runoffs carrying constituents of ignous and limestone rocks.  相似文献   
369.
Cattle treatment with antiparasitic drugs is associated with an important risk exposure for dung beetles. Previous studies demonstrated the impact of some avermectin and pyrethroid compounds on several species such as Onthophagus gazella and Neomyia cornicina. However, little information is available regarding the elimination of these compounds in faeces 8 days after a pour-on administration in dairy cows. The present study, utilising a dairy cow model with cypermethrin treatment, demonstrated that concentrations in dry faeces can reach levels of 5?mg?kg?1 between the first and fourth day after treatment and were present up to 3 months after a single dose of administration at a concentration around 10?µg?kg?1. Faecal samples were purified with three successive columns (silica gel, anion exchange phase, and basic alumina) and analysed by GC-MS. The limit of quantification of this method was 0.5?µg?kg?1. The high sensitivity of the method permitted one to see that the risk exposure of cypermethrin to dung beetles is longer than what was noted in the literature. According to other studies, repeated treatment with such agents may lead to the local extinction of dung beetles. Even if the impact of pyrethroid largely depends on the conditions of the ecosystem where the treated cattle are living, adverse effects of these agents may still occur.  相似文献   
370.
Addressing complex ecological research questions often requires complex empirical experiments. However, due to the logistic constraints of empirical studies there is a trade-off between the complexity of experimental designs and sample size. Here, we explore if the simulation of complex ecological experiments including stochasticity-induced variation can aid in alleviating the sample size limitation of empirical studies. One area where sample size limitations constrain empirical approaches is in studies of the above- and belowground controls of trophic structure. Based on a rule- and individual-based simulation model on the effect of above- and belowground herbivores and their enemies on plant biomass, we evaluate the reliability of biomass estimates, the probability of experimental failure in terms of missing values, and the statistical power of biomass comparisons for a range of sample sizes. As expected, we observed superior performance of setups with sample sizes typical of simulations (n = 1000) as compared to empirical experiments (n = 10). At low sample sizes, simulated standard errors were smaller than expected from statistical theory, indicating that stochastic simulation models may be required in those cases where it is not possible to perform pilot studies for determining sample sizes. To avoid experimental failure, a sample size of n = 30 was required. In conclusion, we propose that the standard tool box of any ecologist should comprise a combination of simulation and empirical approaches to benefit from the realism of empirical experiments as well as the statistical power of simulations.  相似文献   
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