水中氯化物测定的不确定度评定

根据硝酸银滴定法测定水中氯化物的含量，分析了该方法测量不确定度的来源，评定了水中氯化物的测量不确定度，在各不确定度中，以标准溶液配制与样品分析时滴定消耗的硝酸银体积引入的不确定度较大。     

水质铜测定的不确定度评定

根据火焰原子吸收分光光度法测定水中铜的含量，分析了测量不确定度的主要来源，即标准曲线不确定度、标准溶液不确定度、测量重复性不确定度。计算得到水中铜的测定结果的合成不确定度为0．098mg／L，扩展不确定度为0．196mg/L。     

地下水矿化度测定的不确定度评定

分析质量法测量地下水矿化度的测量不确定度来源，评定了地下水矿化度的测量不确定度，在各不确定度中，称量引入的不确定度较大。     

水中阴离子表面活性剂的测量不确定度评定

简要介绍了测量不确定度的概念，运用《测量不确定度评定与表示》的技术规范，通过对阴离子表面活性剂的测定过程，分析了影响阴离子表面活性剂测量不确定度的因素，给出了相对标准不确定度分量，并具体阐明了测量不确定度的评定步骤，得出测量扩展不确定度的结果。     

纳氏试剂分光光度法测定水中氨氮的不确定度评定

通过纳氏试剂分光光度法测定水中氨氮的过程分析，对测定不确定度作出了评估，并得出产生测定不确定度的主要原因。     

重铬酸钾法测定水中COD的不确定度分析

建立了重铬酸钾法测定水中化学需氧量的相对合成标准不确定度的数学模式,应用一个较高浓度的实例,对B类不确定度的分量作了详尽的分析和计算,得出测量扩展不确定度的结果。     

原子荧光法测定水中汞的不确定度评估

以汞为例,论述了原子荧光法测量不确定度的计算及评定分析的方法。     

水中总磷测量的不确定度评定

采用钼酸铵分光光度法测定水中总磷的含量,分析该法测量不确定度的来源,评定水中总磷的测量不确定度。     

气相色谱法测定甲苯的不确定度评定

以甲苯为例,论述了气相色谱法分析的测量不确定度计算及评定的方法。     

用离子色谱仪测定水中的氟的不确定度

根据测量不确定度评定与表示理论,用离子色谱仪测定水中的氟的不确定度,通过推导和计算,得出该法测定水中的氟的扩展不确定度U95=0．31mg／L,υeff=174。为有关部门提供参考。     

平皿计数法测定细菌总数的不确定度评定

根据细菌总数的测定方法,分析了该方法测量不确定度的来源,评定了水中细菌总数的测量不确定度。     

离子选择电极分析法测定标样中氟化物的不确定度评定

通过对离子选择电极法测定标样中氟化物的过程研究，分析了该方法测量不确定度的来源，给出了相对不确定度分量，得出测量扩展不确定度的结果。     

原子吸收法测定降水中的钾、钠、钙、镁的改进

对标准分析方法中的K、Na、Ca、Mg分开测定改进为混合测定。改进法与标准法的校准曲线、精密度与准确度均较为一致。改进法简化了操作程序，提高了工作效率。     

氮掺杂多孔碳电极CDI技术对水中四环素和硬度离子的高效去除

为解决水体中过剩四环素 (tetracycline, TC)与水硬度离子(Ca²⁺和Mg²⁺)等共存带来的复杂环境污染问题,采用分散聚合法将含氮单体聚合成手风琴状碳前驱体并将其碳化后,制备得到氮掺杂多孔碳材料 (nitrogen-doped porous carbon, NPC),采用电容去离子技术考察了NPC电极同步去除不同水体、pH、初始浓度中TC和水硬度离子的能力。结果表明：Langmuir,Freundlich和Temkin模型对NPC样品电吸附TC的吸附等温线分别进行拟合,发现电吸附过程包含了化学吸附、强静电吸附和物理吸附等机制,吸附过程较为复杂;NPC独特的手风琴状层次结构,使得TC的电吸附容量高达854.3 mg·g⁻¹,是传统自吸附的2.4倍 (350.6 mg·g⁻¹);稳定的层次结构与高导电碳网络结构,协同增强了NPC电极的吸附稳定性、再生性和循环稳定性,使其在自然水体中经过200次吸-脱附后吸附容量仍可保持在78%以上。由此可知,基于CDI技术的氮掺杂多孔碳电极能够有效地同步去除水体中的四环素和硬度离子。该研究结果可为复杂水体污染处理提供参考。     

Measurement of Particulate Bound Mercury,Gaseous Elemental Mercury,and Reactive Gaseous Mercury Concentrations by Using an Ambient Air Mercury Collection System

In this investigation, the concentrations of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM) and particulate bound mercury (PBM) in ambient air were measured at the Hung Kuang (traffic) sampling site during September 27 to October 6, 2014. An ambient air mercury collection system (AAMCS) was utilized to measure simultaneously PBM, GEM, and RGM concentrations in ambient air. The results thus obtained demonstrate that the mean concentrations of PBM, GEM, and RGM were 38.57 ± 11.4 (pg/m³), 17.67 ± 5.56 (ng/m³) and 10.78 ± 2.8 (pg/m³), respectively, at this traffic-sampling site. The mean GEM/PBM and GEM/RGM concentration ratios were 458 and 1639, respectively. The results obtained herein demonstrate that AAMCS can be utilized to collect three phases of mercury simultaneously. The mean PBM, GEM, and RGM concentrations herein were compared with others found in Asia, America, Europe and Antarctica. The mean PBM, GEM, and RGM concentrations were found to be lowest in Asia and Antarctica. The mean PBM concentration in Europe was approximately eight times that in this investigation. The mean GEM and RGM concentrations in this study were 1.21 and 170 times those found in the United States.     

Sorption of As, Cd and Tl as influenced by industrial by-products applied to an acidic soil: equilibrium and kinetic experiments

In situ stabilization of toxic elements in contaminated soils by the addition of amendments is being considered as an effective technique for remediation. In this paper, we performed both kinetics and equilibrium-based sorption experiments of three toxic elements (As, Cd and Tl) in soils amended with two by-products (phosphogypsum and sugar foam, rich in gypsum and calcium carbonate, respectively) to ascertain the feasibility of their application for improving the sorption capacity of As, Cd and Tl from the soil at 25, 35 and 50 °C. Kinetic studies indicated that the sorption follows a pseudo-second-order (PSO) kinetics and the sorption is a two-step diffusion process where both film and intraparticle diffusion played important roles in the sorption mechanisms of the elements. The Langmuir isotherms applied for sorption studies showed that the estimated maximum sorption capacity of the elements in control and amended soils decreased in the order of Cd > As > Tl. Using the thermodynamic equilibrium parameters obtained at different temperatures, the thermodynamic constants of sorption (ΔG, ΔH and ΔS) were also evaluated, indicating spontaneous and endothermic nature of the process, except Tl which was exothermic. An optimal scaling procedure was undertaken to determine the relationships between the kinetic and equilibrium sorption parameters. By means of statistical analysis it was seen that these inter-parametric relationships are dependent on the element nature.     

The growth and Cu and Zn uptake of pakchois (Brassica chinesis L.) in an acidic soil as affected by chicken or pig manure

In a pot experiment, pig manure (PM) and chicken manure (CM) were applied to an acidic soil at application rates of 2%, 4% and 8% (W/W) to evaluate their effects on the growth, Cu and Zn uptake and transfer of five cultivars of pakchoi (Brassica chinesis L.). The results showed that alkaline manures significantly increased the biomass of pakchois, and also pH and electrical conductivity of the soil. Both 0.01 M CaCl₂ and 1.0 M NH₄NO₃ salt solutions predict the Zn transfer from soil to pakchois well, but not for Cu. For the cultivar Siyueman, the transfer factors of Cu (or Zn) in the PM treatments were higher than that in the CM treatments. In our experiment the Cu and Zn concentrations in pakchois did not exceed the Chinese Food Hygiene Standard, but more attention should be paid to heavy metals risk on pakchois at lower soil pH and salt impairment by manures application.     

响应面法对泡沫铜阴极电芬顿产H2O2与·OH性能优化

泡沫金属因其三维结构及优良导电性,使其作为电芬顿阴极开始引起学者关注。选择泡沫铜为阴极、石墨棒为阳极,搭建微孔曝气均匀的玻璃反应器,提高体系传质效率,并通过响应面探索体系产H2O2和·OH的机理。用响应面设计3因素(pH、电流、Fe2+初始浓度)3水平实验,得到体系产H2O2和·OH与3种因素之间的非线性回归方程,得到最优条件:当pH=2、电流0.25 A、Fe2+初始浓度为15 μmol·L-1时H2O2产量最大,为457.27 μmol·L-1;当pH=2、电流0.25 A、Fe2+初始浓度为20 μmol·L-1时·OH产量最多,可达18.56 μmol·L-1。根据方差分析,二次模型显著性很高(R2H2O2=0.977 8,R2·OH=0.964 2),能够很好地模拟实验结果。通过铜溶出实验分析得出铜溶出量在0.4~1.8 mg·L-1之间,符合现行污水排入城镇下水道水质标准(CJ 343-2010)。