新丰江水库富营养化现状及其综合防治对策

新丰江水库水质可满足 Ｇ Ｂ３８３８ － ８８ Ⅱ类水质要求, 其营养水平为贫中营养状态; 磷为主要污染物; 氮磷负荷均略大于可接受的纳污负荷。本文还提出了有效控制新丰江水库富营养化进程的若干建议和措施。     

拟除虫菊酯农药在茶叶中应用的安全性评价

采用田间模拟施药与气相色谱法研究了7种拟除虫菊酯农药在茶园生态环境中的降解动态,茶叶加工过程中的降解和泡茶过程的浸出率及其主要影响因子。根据实验结果推算出通过饮茶进入人体的农药量,结合农药的毒理特性,对拟除虫菊酯农药在茶园生态环境中应用的安全性进行了综合评价。结果表明,拟除虫菊酯农药在茶园中应用的安全性显著高于有机磷农药,在拟除虫菊酯农药之间,其安全性也有较大差异。本研究不仅为茶园使用农药的选择提供了依据,而且首次提出了一种农药对人体安全性的定量评价体系。     

一体化A_mO_n工艺BP神经网络数学模型研究

讨论基于BP神经网络一体化AmOn污水处理工艺数学模型的构建。在分析神经网络和一体化AmOn污水处理工艺各自特点的基础上,建立了具有11个输入层节点、5个输出层节点以及包含两层隐含层的BP神经网络,并确定了各隐含层的节点数、网络的权值和阈值。对模型的验证结果表明:BP神经网络模型基本反映了AmOn一体化工艺的主要特点,网络预测出水结果与实测结果相差不大,神经网络模型具有较好的泛化能力。     

含铜多金属复杂矿区的一株浸矿细菌的分离与鉴定

为寻找新的浸矿细菌,从江西城门山矿区硫化矿矿坑水中使用平板分离法得到了一株能够浸矿的细菌,命名为CMS.经电镜和生理生化试验,鉴定该菌株为革兰氏阴性细菌,短杆状,菌体大小为(0.4±0.1)靘祝±0.5)靘, 最适生长温度为25～30 ℃,最适pH值为2.0,化能自养型,能利用亚铁、单质硫和葡萄糖生长,不能利用硫代硫酸钠、蛋白胨生长.16S rRNA系统发育树的结果表明,CMS菌株与嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,简称A.f)AFY菌株位于系统发育树一个同的分支中,相似度99.72%.克隆其代谢系统关键基因亚铁氧化酶(Iro protein)基因并测定其序列,与其他相关菌株比对,结果显示编码区的核酸序列与报道序列完全一致.另外,其铁闪锌矿(ZnFe)S摇瓶浸出试验显示,在浸出28 d后,含菌株的摇瓶的锌离子质量浓度即达到615.50 mg·L-1,而无菌浸出仅有392.25 mg·L-1.     

鼓风曝气充氧性能与曝气器水深关系

应用相似原理,建立曝气器清水充氧性能与曝气器浸没深度变化的数学模式,为曝气器充氧性能科学预测和曝气工艺设计提供可靠的参数。     

镉污染农田农业生态整治与安全高效利用模式

传统的镉污染治理策略多以改造和净化环境、恢复土壤质量为宗旨。作者从有效利用污染农田的角度,提出了农业生态整治策略,即将污染农田作为一种特殊资源,通过发掘利用生物（植物）自身的耐（抗）镉基因,使污染土地在农业领域重新获得安全而高效的利用。介绍了对某铀矿区近40hm²镉污染农田进行治理利用的成功实践。通过采用桑蚕生产模式替代粮作生产模式,杜绝了污灌污染,消除了食物链中镉的危害,使土壤生产力得到恢复,农田年均产值比水稻模式提高2880元/hm²,比种玉米提高8880元/hm²,利税增加1980元/hm²,耕层土壤镉含量年平均下降1.33mg/kg。还论述了镉在桑树中的分布特征及其对桑树生长和蚕茧质量的影响。     

UV/草酸铁/H2O2法处理乙草胺废水的研究

对UV/草酸铁/H2O2法处理乙草胺废水进行研究,考察了H2O2浓度、FeSO4浓度、K2C2O4浓度、pH值及反应时间对乙草胺去除效果的影响.结果表明,当H2O2/FeSO4/K2C2O4(化学剂量数比)=5051,H2O2/乙草胺初始COD(质量浓度比)=31时,该技术对乙草胺的去除率可达85%以上.这表明,采用UV/草酸铁/H2O2法可以有效地处理含乙草胺废水.     

Synthesis and characterization of magnetic Fe3O4@CaSiO3 composites and evaluation of their adsorption characteristics for heavy metal ions

A two-component material (Fe₃O₄@CaSiO₃) with an Fe₃O₄ magnetite core and layered porous CaSiO₃ shell from calcium nitrate and sodium silicate was synthesized by precipitation. The structure, morphology, magnetic properties, and composition of the Fe₃O₄@CaSiO₃ composite were characterized in detail, and its adsorption performance, adsorption kinetics, and recyclability for Cu²⁺, Ni²⁺, and Cr³⁺ adsorption were studied. The Fe₃O₄@CaSiO₃ composite has a 2D core–layer architecture with a cotton-like morphology, specific surface area of 41.56 m²/g, pore size of 16 nm, and pore volume of 0.25 cm³/g. The measured magnetization saturation values of the magnetic composite were 57.1 emu/g. Data of the adsorption of Cu²⁺, Ni²⁺, and Cr³⁺ by Fe₃O₄@CaSiO₃ fitted the Redlich–Peterson and pseudo-second-order models well, and all adsorption processes reached equilibrium within 150 min. The maximum adsorption capacities of Fe₃O₄@CaSiO₃ toward Cu²⁺, Ni²⁺, and Cr³⁺ were 427.10, 391.59, and 371.39 mg/g at an initial concentration of 225 mg/L and a temperature of 293 K according to the fitted curve with the Redlich–Peterson model, respectively. All adsorption were spontaneous endothermic processes featuring an entropy increase, including physisorption, chemisorption, and ion exchange; among these process, chemisorption was the primary mechanism. Fe₃O₄@CaSiO₃ exhibited excellent adsorption, regeneration, and magnetic separation performance, thereby demonstrating its potential applicability to removing heavy metal ions.

     

Performance of biotic indices in comparison to chemical-based Water Quality Index (WQI) in evaluating the water quality of urban river

In order to evaluate the water quality of one of the most polluted urban river in Malaysia, the Penchala River, performance of eight biotic indices, Biomonitoring Working Party (BMWP), BMWP^Thai, BMWP^Viet, Average Score Per Taxon (ASPT), ASPT^Thai, BMWP^Viet, Family Biotic Index (FBI), and Singapore Biotic Index (SingScore), was compared. The water quality categorization based on these biotic indices was then compared with the categorization of Malaysian Water Quality Index (WQI) derived from measurements of six water physicochemical parameters (pH, BOD, COD, NH₃-N, DO, and TSS). The river was divided into four sections: upstream section (recreational area), middle stream 1 (residential area), middle stream 2 (commercial area), and downstream. Abundance and diversity of the macroinvertebrates were the highest in the upstream section (407 individual and H′?=?1.56, respectively), followed by the middle stream 1 (356 individual and H′?=?0.82). The least abundance was recorded in the downstream section (214 individual). Among all biotic indices, BMWP was the most reliable in evaluating the water quality of this urban river as their classifications were comparable to the WQI. BMWPs in this study have strong relationships with dissolved oxygen (DO) content. Our results demonstrated that the biotic indices were more sensitive towards organic pollution than the WQI. BMWP indices especially BMWP^Viet were the most reliable and could be adopted along with the WQI for assessment of water quality in urban rivers.     

Production of activated carbon from walnut shell by CO2 activation in a fluidized bed reactor and its adsorption performance of copper ion

Journal of Material Cycles and Waste Management - Low-cost and effective activated carbon for copper ion adsorption was prepared from walnut shell by CO2 activation in a fluidized bed. The effects...