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Bruce W. Loum W. Thomas Shoaf 《Journal of the American Water Resources Association》1978,14(1):190-194
Abstract: Chlorophyll analyses of both laboratory cultures and natural aquatic samples were unaffected by the use of magnesium carbonate. Equal volumes of the samples (at various pH values) were pipetted onto 0.45 micrometer filters with and without magnesium carbonate. Chlorophyll concentrations were determined for each filtered sample and those frozen for specified times. In all samples tested there was no difference either in the retention of algae or in the stability of chlorophyll over the time period and pH range tested. 相似文献
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F. Gallardo‐Lara M. Azcón A. Polo 《Journal of environmental science and health. Part. B》2013,48(5):623-643
Abstract Land disposal of olive oil wastewater using it as a soil amendment requires a knowledge of the effects that its application may produce on the status of the mineral nutrients in the plant‐soil system. A pot experiment using calcareous soil was performed in a growth chamber to examine the effects of olive oil wastewater on the availability and postharvest soil extractability of K, Mg and Mn. The experiment included 6 treatments: two rates of olive oil wastewater, two mineral fertilizer treatments containing K (which supplied K in amounts equivalent to the K supplied by the olive oil wastewater treatments), a K‐free mineral fertilizer treatment, and a control. The pots were sown with ryegrass as the test plant, harvesting 3 times at intervals of one month. Olive oil wastewater has demonstrated a considerable capacity for supplying K that can be assimilated by the plant, tending in fact to surpass the mineral potassium fertilizer tested. The application of olive oil wastewater tends to reduce the concentration of Mg in the plant, similarly to the effect of adding mineral potassium fertilizer. An enhancement of Mn availability takes place in the soil amended with olive oil wastewater, which on occasion has produced Mn concentrations in plant that could be considered phytotoxic or at least excessive. After harvesting, we observed an increase in the amount of exchangeable K in soil with added industrial wastewater. However, these increases are lower than those in soil treated with mineral potassium fertilizer. The levels of exchangeable, carbonate‐bound, organic‐bound and residual Mg in soil were higher in treatments incorporating olive oil wastewater than in those with added mineral K, with the opposite tendency occurring in the amount of Fe‐Mn oxides‐bound Mg in soil. Treatments based on olive oil wastewater, especially in high doses, increased the amount of exchangeable and carbonate‐bound Mn in soil, in comparison with treatments adding mineral fertilizers with or without K. In contrast, the addition of industrial wastewater caused a drop in the amount of Fe‐Mn oxides‐bound and organic‐bound Mn in soil. 相似文献
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为了及时有效地监测与控制危险环境中的易燃易爆危险品,设计并组建了实验室条件下模拟监控应用系统,通过组态软件完成实时监测与控制.对模拟试验中数据处理方法和参数设计也进行了相关研究. 相似文献
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目的 研究化学法退除DZ125合金HY3包覆型涂层。方法 采用真空电弧镀技术(AIP)在定向凝固镍基高温合金DZ125上制备包覆型涂层HY3,利用化学方法完全退除基体上的涂层,通过失重法研究对比1#和2#退除溶液退除HY3涂层和DZ125合金的退除速率,采用扫描电镜(SEM)对退除后的HY3涂层和DZ125基体的微观组织进行观察。结果 经过100 min,2#溶液可以将20 ?m左右的HY3涂层完全退除,采用1#溶液需要超过100 min才能完全退除涂层。两种对DZ125合金的腐蚀性很小,对于同一种合金而言,1#溶液和2#溶液对合金的腐蚀速率比值为1︰13。在1#溶液中,合金与涂层腐蚀速率的比值为1︰87.65;在2#退除溶液中,合金与涂层腐蚀速率的比值为1︰6.81。结论 1#溶液更加适合退除DZ125合金上的HY3涂层。 相似文献
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采用水解酸化-磷酸铵镁(MAP)法-EGSB组合工艺对大豆蛋白废水进行处理,考察了水解酸化系统运行效果,并对其运行参数进行优化;提出MAP法对高浓度氨氮废水的处理方法,并评选其处理高浓度氨氮废水的适宜条件。结果表明,水解酸化系统运行稳定,最适pH为7.0,最佳水力停留时间为12 h,氨氮转化率高达95.8%;MAP法处理高浓度氨氮废水的优选条件为n(Mg):n(N):n(P)=1:1:0.8,此条件下氨氮去除率为88.3%,磷酸去除率为76.7%;EGSB反应器经过三个月的启动后可稳定运行,有机负荷高达到9.88 kg·(m3·d)-1,COD去除率达到90.0%左右。水解酸化-MAP-EGSB组合工艺在处理大豆蛋白废水时可获得连续稳定的处理效果,为大豆蛋白废水处理的工程化提供了基础依据。 相似文献
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