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441.
文章介绍了废干电池的“热解-酸溶-同槽电解”组合工艺中的酸溶技术及溶液净化的工艺条件研究。 相似文献
442.
以稀盐酸为吸收液,用气相色谱法测定环境空气中痕量三乙胺,结果表明0.1mol/LHCL和0.2mol/LHCL是环境空气中痕量三乙胺的有效吸收液,吸收后样品稳定性良好。在优化的色谱条件下,气相色谱直接进样,FID检测器测定吸收液中的三乙胺线性好、操作简便、精密度高、检出限低,回收率符合要求。 相似文献
443.
电解制备高效聚合铝的溶液化学因素 总被引:9,自引:0,他引:9
采用电化学方法合成聚合氯化铝,通过在线有效控制电解过程的关键参数,可以年鉴轩出高碱化度,高Alb含量的PAC液体产品,本文研究了PAC电合成的重要溶液化学因素,如电解液的性质、浓度、组成、pH、离子迁移,形态转化等,从而提出了制备设定浓度和碱化度的PAC的最佳溶液化学条件,并证明溶液化学因素与电量参数之间具有必然联系。 相似文献
444.
445.
St-Pierre C Martel R Gabriel U Lefebvre R Robert T Hawari J 《Journal of contaminant hydrology》2004,71(1-4):155-192
Forty-one phase diagrams and fifteen sand column experiments were conducted to evaluate the efficiency of three types of washing solutions to recover trichloroethylene (TCE) at residual saturation and to identify the recovery mechanisms involved. This study demonstrates that: (1) an alcohol and a surfactant combination is more efficient than an alcohol used alone in water; (2) the prediction of the dominant recovery mechanism from the tie line slopes in phase diagram is accurate and can be reproduced in sand column experiments; and (3) TCE recovery efficiency in sand column experiments is generally well represented by the position of the miscibility curve in phase diagrams in the low concentration range. However, the miscibility curve alone is not sufficient to exactly predict the TCE recovery mechanisms involved. Tie line slopes and the critical tie line have to be taken into consideration to select the active matter as well as its concentration and to predict the dominant recovery mechanism in sand column experiments. The sand column experiments quantified the recovery efficiency of each solution and identified the proportion of the recovery mechanisms (mobilisation vs. solubilisation). Washing solutions with an active matter concentration above the critical tie line caused dominating mobilisation. Mobilisation was also dominant when the active matter of the washing solution partitioned into the organic phase and the active matter concentration was below the critical tie line. Solubilisation and emulsification were dominant for washing solutions containing active matter, which principally partitioned into the aqueous phase and an active matter concentration below the critical tie line. 相似文献
446.
通过对聚丙烯腈和聚砜超滤膜与明胶蛋白的性能行为和不同因素对膜性能影响的研究,表明聚丙烯腈中空纤维超滤膜是用于处理废彩色显影液的较好膜品种。中空纤维超滤器具有水流状态好,投资、维修费用低,处理效率高和回收投资时间短等优点。 相似文献
447.
城厢镇地表水水源的污染特点在很大程度上取决于浏河闸的运行启闭情况,对通过引排水方案来改善滞流期恶劣的水质状况.文中首先用一维Saint—Venant方程组及CBOD—NBOD—DO联偶反应方程组分别建立水量及水质模式,通过有限差分法数值求解.利用1990年11月5日开闸排水期间水量与水质同步监测资料进行验证,结果表明,模式能够满足水质规划的要求.本文对水质的动态变化规律进行评价,认为只要合理组合引排方案,就能达到改善城厢镇地表水源水质的目的. 相似文献
448.
S.?Nélieu L.?Kerhoas M.?Sarakha J.?EinhornEmail author 《Environmental Chemistry Letters》2004,2(2):83-87
Here we evidenced the photo-induced degradation of monolinuron, a phenylurea herbicide, through the 300–450 nm light excitation of nitrite and nitrate species. The degradation pathways were compared to those obtained under direct photolysis at 254 nm. When using NO3– and NO2– as photoinducers, hydroxyphenyl-substituted photodegradation products were found to be formed specifically through the involvement of OH° radicals. NO– and NO2-phenyl substituted compounds were also observed as a result of the production of NO° and NO2° radicals. Half-lives of monolinuron in aqueous solutions were measured in various conditions of concentrations of substrate and inducer, oxygen content and pH. 相似文献
449.
Effects of the Interactions Between Selenium and Phosphorus on the Growth and Selenium Accumulation in Rice (Oryza Sativa) 总被引:2,自引:0,他引:2
The solution culture, paddy soil culture and the simulation experiments in the laboratory were conducted to clarify the interactions between selenium and phosphorus, and its effects on the growth and selenium accumulation in rice. Results revealed that a suitable supply of selenium could promote rice growth and excessive selenium could injure rice plant, causing lower biomass, especially in the roots. The supply of selenite could enhance the selenium contents of rice shoots and roots in solution culture and in soil culture. The selenium concentrations in roots were much higher than those in shoots supplied with the same rates of selenium and phosphorus. The interaction between selenium and phosphorus was evident. When the phosphorus supply increased to meet the needs of plant growth, phosphorus could promote absorption and accumulation of selenium in the shoots. If the phosphorus supply was excessive, phosphorus could inhibit the accumulation of selenium in the shoots at the lower selenite level (2 mol l–1), but could not at the higher selenite level (10 mol l–1). With the supply of phosphate increased, the selenium concentrations in the roots decreased significantly at both selenite levels. The presence of phosphate could decrease Se sorption on the soil surface and increase the selenium concentration in the soil solution. The concentrations of selenium in shoots and roots supplied with 0.08 g kg–1 phosphorus were lower than those with no phosphorus supplied. With the increase of phosphorus added to 0.4 g kg–1, the selenium concentration in shoots and roots increased. The effect of phosphorus on the concentration was statistically significant at all three selenium levels. 相似文献
450.