N-甲基咪唑配体络合金属Cu(Ⅰ)催化剂对水中2,4-二甲氧基溴苯还原脱溴

合成了以N-甲基咪唑为配体,Cu为活性中心的络合金属多相催化剂Cu(Ⅰ)-NHC-SBA-15.通过1H-NMR、13C-NMR、有机元素分析和FTIR对各步合成反应产物结构经行了鉴定;用SEM、N2吸附脱附等方法对催化剂进行了表征;用ICP测定了催化剂Cu含量.对催化剂催化2,4-二甲氧基溴苯还原脱溴活性进行了测试.在反应时间为24 h,通过正交实验和单因素实验,考察了催化剂用量、反应温度、还原剂用量等因素对脱溴率的影响,并确定了最佳反应条件:催化剂用量为0.05 g、水合肼用量为2 mL、反应温度为80℃,脱溴效果较好,脱溴率达到98.5％.对催化剂重复使用进行了初步研究.对催化反应动力学进行了初步研究,结果表明,该多相催化反应是由表面反应速度控制,并符合一级动力学反应.对反应机理进行了初步探讨.     

纳米片自组装原位N掺杂(BiO)2CO3分级微球的可控合成及其优异可见光催化性能

以二氰二胺和柠檬酸铋为原料,采用一步水热法合成原位N掺杂(BiO)2CO3纳米片自组装分等级微球结构。采用XRD、SEM、XPS、FT-IR、UV-Vis DRS和PL等对合成的材料进行表征,结果表明,不同二氰二胺加入量会对(BiO)2CO3的形貌结构、禁带宽度以及电子-空穴复合率产生显著影响。二氰二胺在水热过程水解柠檬酸铋,同时N原子原位掺杂进入(BiO)2CO3晶格。N掺杂使(BiO)2CO3的光响应范围大幅拓展至可见光,通过价带XPS获得了掺杂N元素减小(BiO)2CO3禁带宽度的证据。在可见光照射下,原位N掺杂(BiO)2CO3分等级微球结构表现出对液相罗丹明B和气相NO优异的可见光催化降解活性,高于N掺杂TiO2和C掺杂TiO2。研究结果对拓展N掺杂作用向非TiO2体系的转变具有重要意义。     

Cu-SBA-15催化湿式过氧化氢氧化水溶液中罗丹明B

采用水热晶化法合成了不同含铜量的Cu-SBA-15介孔分子筛,并且用XRD、N2吸附、TEM以及UV-vis对所合成的样品进行表征。以Cu-SBA-15为催化剂,H2O2为氧化剂,催化湿式过氧化水溶液中的罗丹明B,主要考察H2O2浓度、催化剂用量、处理温度、初始pH等因素对罗丹明B氧化效果的影响。结果表明,在同样的处理条件下罗丹明的脱色率明显高于TOC去除率,处理温度、初始pH对罗丹明B的脱色与氧化有重要影响。在罗丹明B初始浓度100 mg/L,H2O2初始浓度1.8 g/L,催化剂量0.3 g/L,温度60℃,pH为7.0,处理时间100 min时,罗丹明B的脱色率为98.6%,TOC去除率为62.8%。     

春季角毛藻对N/P值响应的FRD判别

首次运用FRD判别法,探讨了角毛藻(Chaetocerossp.)生长对N/P值的响应过程。通过大亚湾春季现场观测的角毛藻细胞数量与DIN/PO4比值关系分析,构建关系曲线的完全样本进行泛函回归分割(FRD)判别。FRD判别表明,角毛藻是以3种不同的生长状况响应N/P值变化,即在N/P<15.79(±1.41)时,角毛藻数量随N/P值增大处于缓慢生长状况;在N/P=15.79(±1.41)～59.90(±4.28)之间时,角毛藻数量则随N/P值增大而迅速增长;而当N/P>59.90(±4 28)时,角毛藻数量达到最大生长值,并处于上下涨落状态。     

南京市生态系统服务价值评估

参照Constaza等提出的方法,估算了2000年-2005年南京市生态系统服务价值及变化。结果表明,2000年南京市生态系统服务总价值为6．69×10^9元,2005年的总价值为7．40×10^9元,5年内增加了7．1×10^9元,主要为水域面积增加所致。     

岩溶农业区地下河流域硝酸盐污染来源——以重庆青木关岩溶区为例

于2010年6月—10月每月对青木关地下河水进行监测,利用15N同位素技术并结合水化学指标,分析地下河的水化学特征以及硝态氮来源的时空变化特征。结果表明,地下河出口丁家龙洞硝态氮质量浓度（5.08 mg/L）比入口天池2号点（0.842 mg/L）高6倍多。天池2号点处δ15N为-0.705%~+0.706%,主要受到人造化肥和天然土壤矿化的有机氮的影响,总体变化幅度不大,地下水受外界影响较小。出口丁家龙洞处的δ15N为-2.15%~+3.78%,平均值为+1.01%,总体值高,且变化幅度大。     

Minerals policy in Europe: Some recent developments

The importance of a secured supply of raw materials for the European economy is evident. However, securing the supply of raw materials based on an appropriate EU minerals policy has been scarcely treated by the decision-makers in the last decades. Solely the impact of price development of international commodity markets in the last years induces a re-thinking of this field. The EU Raw Materials Initiative, which was published by the European Commission in November 2008, establishes an EU raw materials strategy including a list of actions.     

Comprehensive quality assessment of municipal organic waste composts produced by different preparation methods

In the first part of this work, the effect of municipal organic waste (MOW) composts on plant growth was evaluated in a greenhouse trial. The treatments included soil amended with 14 different composts (prepared by shredding, adding wood shavings, cocomposting with biosolids or vermicomposting), an inorganically fertilized soil, and a control soil. All of the treatments significantly increased plant growth compared to the control, and yields of three of the amended treatments were as high as that of the inorganic fertilizer treatment. When comparing differently prepared composts to the conventional compost, it was found that cocomposting MOW with biosolids was the method which most positively influenced yields (26-41% yield increases). In the second part of this work, we evaluated the effects of the different preparation methods on compost quality, using a multivariate approach. Three main quality aspects were considered collectively in a principal component analysis: organic matter and nutrient concentrations, degradability and capacity to mineralize these nutrients, and plant growth. The model was restricted to the first and second components (PC1 and PC1) which accounted for 94% of data variance. On the resulting factorial plane, four groups were distinguished. Each of the groups was compared to the reference compost to determine quality increases or decreases. Based on this analysis, it was found that cocomposting MOW with biosolids produced the highest quality products (higher total nutrient and OM concentration, nutrient mineralization potential, and plant growth). Addition of wood shavings increased OM concentration, but reduced quality in terms of the other aspects studied. Shredding was only effective to increase product quality when it was not combined with other methods, whereas vermicomposting only increased quality when MOW was not mixed with biosolids.     

沛沿河流域土壤肥料释放的降雨模拟研究

为有效控制农业面源污染,改善沛沿河流域水质状况,通过对水稻田、杨树林和果园的土壤分别施用不同类型化肥后,模拟研究了土壤在受雨水短期浸泡及连续降雨情况下氮、磷的释放特征。研究结果表明,稻田土壤对氮磷的保肥能力最佳,施肥时应以基肥为主;果园土壤及林地土壤的保肥能力均劣于稻田土壤,应采用少量多次追肥的方法。尿素与碳铵宜做基肥使用,而氯化铵与硫酸铵宜做追肥使用。     

N2O回收利用及减排技术研究进展

减排N₂O对控制地球温室效应和保护人类健康具有重要的意义。综述了有关分离纯化N₂O的技术及N₂O回收利用于芳烃氧化制苯酚的研究进展,介绍了N₂O的热分解及催化分解等减排技术的研究成果。指出：采用N₂O直接氧化芳烃制苯酚技术需要解决的技术关键是开发高选择性的催化剂;催化分解是目前可行的N₂O减排技术,而制备高活性且抗O₂、水蒸气及硫化物干扰的催化剂是今后的研究热点。