Pb2+、Cu2+、Cd2+在胡敏酸上的吸附和竞争吸附

研究了金属离子Pb2+、Cu2+、Cd2+在胡敏酸上的单一吸附和两两组分竞争吸附.结果表明,总体胡敏酸对Cu2+、Pb2+的吸附明显强于Cd2+.Freundlich方程对Pb2+、Cd2+单一金属离子吸附等温线的拟合呈极显著关系,Langmuir方程为胡敏酸吸附Cu2+的最佳拟合方程.Pb2+、Cu2+、Cd2+的两两组分竞争吸附表明,胡敏酸对3种离子均具有"选择性吸附",竞争能力从大到小依次为Pb2+、Cu2+、Cd2+.     

Corrosion and polarization behavior of carbon steel in MEA-based CO2 capture process

This work reveals levels of corrosion rate and polarization behavior of carbon steel immersed in aqueous solutions of monoethanolamine (MEA) used in the absorption-based carbon dioxide (CO₂) capture process for greenhouse gas reduction from industrial flue gas streams. Such information was obtained from electrochemical-based corrosion experiments under a wide range of the CO₂ capture process conditions. The corrosion of carbon steel was evaluated in respect to process parameters including partial pressure of oxygen (O₂), CO₂ loading in solution, solution velocity, solution temperature, MEA concentration and metal surface condition. Results show that the aqueous MEA solution containing CO₂ provides a favorable condition for the corrosion of carbon steel to proceed. Corrosion rate is increased by all tested process parameters. These parametric effects were explained by the electrochemical kinetic data obtained from polarization curves and by the thermodynamic data obtained from Pourbaix diagram.     

无花果曲霉对Cu^2＋吸附的研究

采用生物吸附法,研究了经过预处理的无花果曲霉对Cu^2 吸附行为与影响吸附的主要因素,具体包括菌丝球与Cu^2 接触反应时间、Cu^2 浓度、原初pH值3个方面。结果表明：该菌丝球在吸附进行5min时,吸附量已达量2．855mg/g,在吸附进行4h以后趋于平衡。最佳pH范围为4．0－5．0,Cu62 浓度在20－100mg/L范围内吸附量为2．763－4．713mg/g,而吸附率却为32．31％－9．54％。其吸附行为在一定的温度和一定浓度范围内较好地符合Langmuir吸附等温模型。     

Cd-Pb复合污染在土壤-水稻系统中生态效应的研究

采用盆栽试验研究了重金属复合污染物在土壤 -水稻系统中迁移、积累规律及生态效应。结果表明 :Cd、Pb复合污染使水稻株高比对照的下降了 5～ 7cm ,水稻减产 2 0 % ,2元素交互作用特别是 5元素复合作用影响了水稻的正常生长发育 ;不同处理中重金属在水稻籽实的分配比例依次为 5元素 >2元素 >单元素 ;Cd -Pb 2元素交互作用时 ,Pb元素的存在促进了水稻对Cd元素的吸收 ,而Cd元素却抑制了水稻对Pb元素的吸收 ;Cd比Pb元素易向地上部迁移 ,Pb元素大部分积累于水稻根部     

Accumulation, speciation and cellular localization of copper in Sesbania drummondii

Growth, accumulation and intracellular speciation and distribution of copper (Cu) in Sesbania drummondii was studied using scanning-electron microscopy (SEM), X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS). The growth of seedlings was assessed in terms of biomass accumulation. The growth of the seedling was enhanced by 73.5% at a low Cu concentration (50 mg l⁻¹) compared to the control treatment. Additionally, seedling growth was inhibited by 18% at 300 mg l⁻¹ Cu with respect to the control. Copper concentration in roots and shoots was increased with increasing Cu concentration in the growth solution. The accumulation of Cu was found to be higher in roots than in the shoots. At a concentration of 300 mg l⁻¹ Cu, the roots accumulated 27,440 mg Cu kg⁻¹ dry weight (dw) while shoots accumulated 1282 mg Cu kg⁻¹ dw. Seedlings were assessed for photosynthetic activity by measuring chlorophyll a fluorescence parameters: F_v/F_m and F_v/F₀ values. Photosynthetic integrity was not affected by any of the Cu treatments. The X-ray absorption spectroscopic (XAS) studies showed that Cu was predominantly present as Cu(II) in Sesbania tissue. In addition, from the XAS studies it was shown that the Cu exists in a mixture of different coordination states consisting of Cu bound to sugars and small organic acids with some possible precipitated copper oxide. From the EXAFS studies, the coordination of Cu was determined to have four equatorial oxygen(nitrogen) ligands at 1.96 Å and two axial oxygen ligands at 2.31 Å. Scanning-electron microscopy studies revealed the distribution of Cu within the seedlings tissues, predominantly accumulated in the cortical and vascular (xylem) regions of root tissues. In the stem, most of the Cu was found within the xylem tissue. However, the deposition of Cu within the leaf tissues was in the parenchyma. The present study demonstrates the mechanisms employed by S. drummondii for Cu uptake and its biotransformation.     

铜/海泡石催化氧化CO和催化还原NOx性能的研究

采用浸渍法制备铜/海泡石催化剂,考察其催化氧化CO和催化还原NOx性能以及预处理条件和掺加稀土元素对其性能的影响,并用XRD、BET技术对其进行表征.盐酸和硝酸改性的海泡石载体都能使铜/海泡石在190℃左右将CO完全转化;稀土元素的添加对铜/海泡石催化氧化CO的活性没有显著影响;铜/海泡石对NOx有一定的催化还原性能,添加稀土后对其催化还原活性有明显促进作用.     

德兴铜矿周边土壤中铜的形态分布

采用Tessier连续逐级形态提取方法,研究了德兴铜矿土壤中铜存在的化学形态和生物可利用性。结果表明,德兴铜矿各功能区表层土壤均已受到不同程度的Cu污染,分布趋势为尾矿库>采矿区>菜田>稻田>生活区。表层土壤中Cu的直接利用性不高,但可利用态Cu所占比例较高,可能造成潜在的生态毒性。土壤剖面中Cu的化学形态分布趋势为残余态>有机结合态>氧化态>碳酸盐结合态>可交换态,各态的跃迁能力都较差,基本不会威胁到该地区的地下水源。     

膜法脱盐技术在钢铁企业污水回用中的应用分析

钢铁企业综合污水处理厂的出水脱盐处理回用具有重要意义,本文对国内一些钢铁企业采用的膜法脱盐技术的优缺点进行了分析,并提出了改进方案。     

钢铁厂废酸对印染前处理废水的混凝沉淀实验

棉纺织印染前处理废水水质成分复杂,污染物含量极高,是印染厂污水处理难以达标的重要原因。实验针对常州某印染厂棉纺织印染前处理车间废水水质特性,选取钢铁厂废酸作为混凝剂对棉纺织印染前处理废水进行了混凝试验研究。得出废酸的最佳投加量为30mL/L;混凝最佳搅拌方式为：以300rpm速度快速搅拌2min,以40rpm搅拌10min;助凝剂阳离子型聚丙烯酰胺（CPAM）以投加4mg/L为宜;最佳沉淀时间为20min。     

油气输送焊管残余应力测试与安全评价方法研究

针对油气输送焊管残余应力测试与评估技术难题,采用机械切割应力释放法对不同成型工艺和状态焊管的残余应力进行了测试分析对比,结果表明:UOE焊管的残余应力分布水平较低;ERW焊管次之;SSAW焊管的残余应力分布范围较广,有高有低。不同管型和成型工艺及水压试验状态具有明显不同的残余应力分布特征,在进行焊管安全评价时必须区别对待。根据残余应力实测结果提出了焊管安全评价时残余应力的取值建议。研究结果对管道设计、安全分析与评价、焊管残余应力的改善、控制及焊管合理选用具有重要工程意义。