流动注射在线过硫酸盐消解测定水中的总氮

建立在线碱性过硫酸盐/紫外氧化流动注射光度法测定水中总氮的方法,该方法的检出限为4.74μg/L,回收率为97.4%~100.8%,相对标准偏差为1.5%~2.2%。方法简单、快速及检出限符合地表水检测限的要求。     

流动注射分光光度法测定水中氯化氰的研究

该文通过改良流动注射在线蒸馏法测定饮用天然矿泉水中氰化物的标准方法 (GB/T8538-2008),研究出流动注射分光光度法测定水中氯化氰的简易、快速分析方法,同时研究了氯化氰测定的影响因素。研究结果表明,该法线性系数为0.99999,检出限(MDL)为0.0004mg/L(以CN-计),0.010mg/L的低浓度和0.090mg/L的高浓度标准样品测定相对标准偏差分别为1.6%和1.3%,空白加标和实际样品加标回收率分别为104.7%和99.9%,显色温度、显色剂浓度及缓冲盐体系对水中氯化氰的测定结果影响显著。     

在线消解流动注射光度法测定水中总磷的应用

建立在线消解流动注射光度法测定水中总磷含量的方法,该方法的检出限为0.003mg/L,回收率为95.6%—103.1%,相对标准偏差为0.92%—1.88%。方法简单、快速及检出限符合地表水检测限的要求。该方法在参加能力验证考核中取得满意成绩。     

麝香草酚分光光度法测定硝酸盐氮废液中银的回收

本文详细介绍了在饮用水水质检测实验室用麝香草酚分光光度法测定硝酸盐氮和二氮杂菲分光光度法测定铁两种废液混合沉淀氯化银,在酸性条件下使用铁还原银,对其进行回收的方法。得出其回收率为:84.3%。     

反相流动注射催化光度法测定废水中的铬(Ⅵ)

在硫酸介质中,铬(Ⅵ)对溴酸钾氧化甲基橙褪色反应有显著的催化作用。将反相流动注射分析技术应用于该反应体系,建立了一种快速测定铬(Ⅵ)的分析方法。在优化试验条件下,铬(Ⅵ)的线性范围为0～3.0 mg/L,检出限为0.03 mg/L。采用该方法测定工业废水和电镀废液中的铬(Ⅵ),其相对标准偏差≤1.2%,加标回收率为94.5%～96.7%,结果令人满意。     

砷铈催化分光光度法测定尿碘两种消解方式的比较

目的比较用砷铈催化分光光度法测定尿碘的两种消解方式。方法用多孔消化器(石墨导热方式)和水浴恒温振荡器(水浴导热方式)两种方法消解样品,用砷铈催化分光光度法测定尿中碘的含量。结果两种方法分别测定3种质量浓度的尿中碘国家标准物质,结果均符合允许误差要求。结论两种方法均适用于砷铈催化分光光度法测定尿中碘含量,但水浴恒温振荡器消解法更经济实用。     

二氮杂菲分光光度法测定水中总铁、不沉降铁、可滤性铁

通过二氮杂菲分光光度法测定总铁、不沉降铁、可滤性铁．对水厂的水源水和出厂水中三种铁进行测定。结果表明,水源水和出厂水中总铁≥不沉降铁≥可滤性铁．水源水总铁含量高,远远超出地表水环境质量标准GB3838—2002标准限值0．30mg/L．可滤性铁基本在此限值以内,出厂水里这三种铁基本相同。结合实际情况,水源水测定铁含量时。建议采用普通滤纸过滤然后用二氮杂菲分光光度法测定可滤性铁的形式。     

电感耦合等离子体原子发射光谱法(ICP-AES)测定地下水中多种元素

应用电感耦合等离子体原子发射光谱法(ICP-AES)测定地下水中钾、钠、钙、镁、铁、锰元素的含量,使用分光光度法测定氟的含量,测定的相对标准偏差为0.7%~2.8%,加标回收率为92.1%~105.2%。结果表明,大部分地区地下水中钠和氟化物的含量均偏高,常量与微量元素的组成含量差别不大。     

分光光度法测定水中铁含量

为避免铁结成的水垢影响锅炉的安全运行，要求锅炉给水必须达到一定标准，对铁的测定显得尤为重要，文章讨论了分光光度法对水中铁的测定。     

渔业水体中非离子氨的危害及检测方法的研究

非离子氨是反映渔业水体污染的重要指标之一。本文阐述了非离子氨对渔业水体的危害以及渔业水体中非离子氨与氨氮的转化关系,并对检测氨氮的方法进行了对比和分析。结果表明,流动注射-水杨酸光度法可以准确、快速测定渔业水体中氨氮值及非离子氨值。     

生物除铁除锰滤池对As（V）的去除效果研究

采用人工配水模拟天然水体,考察了生物除铁除锰滤池对As（V）的去除性能。结果表明,当原水As（V）含量不高于200wg／L时,生物除铁除锰滤池对铁、锰的去除效果不受砷的影响,且As（V）去除率可达到95％以上,出水铁、锰及砷含量均满足标准限值要求;生物除铁除锰滤池对As（V）的去除主要发生在深度为0～660mm的滤层内;滤柱在反冲洗后,短时期内会出现砷、铁含量超标现象。     

固定化菌种处理锈蚀管网出水的研究

发生内腐蚀的管道出水往往使出厂饮用水水质部分超标,遂进行了相关的深度净化技术研究。从除铁除锰滤池中的成熟滤砂洗脱下滤膜,以铁锰细菌的选择性培养基进行分离纯化,共培养出5株铁锰降解菌。通过试验发现,铁锰降解菌在铁、锰共存的培养基中的生长情况要好于只含铁基质的,而在只含有锰的基质中不生长。将降解有机物的工程菌和铁锰降解菌固定在同一个反应器的不同滤料上并处理管网出水(浊度为1.5NTU、色度≥25倍、有腥味),结果表明,一体式固定菌种反应器对铁、锰和高锰酸盐指数的去除率可达98%、96%和55%,处理出水的浊度<0.5NTU,色度<15倍,没有嗅味。     

硫酸根和碱度变化对管网铁释放的影响

针对水源切换后给水管网中出现的水质超标现象,开展了硫酸根浓度和碱度变化对管垢铁释放的影响研究。利用实验室管段模拟反应器,对比分析了不同硫酸根浓度和碱度对管垢铁释放的影响差异。结果表明,硫酸根浓度增加造成管网水质恶化的响应速度与硫酸根浓度呈正相关,硫酸根浓度越高则响应速度越快。在管垢铁释放的影响因素中,和碱度相比,硫酸根浓度是首要影响因素。在低浓度硫酸根对管垢铁释放无明显影响的情况下,碱度变化对管垢铁释放也基本无影响;而在高浓度硫酸根造成管垢溶解破坏发生铁释放的情况下,随着碱度的降低,铁的释放量明显增加。     

Low-Cost Separation of Arsenic from Water: With Special Reference to Bangladesh

The main objective of the study was to develop a low-cost technique for the removal of arsenic from contaminated groundwater, as found in Bangladesh. It was shown that arsenic can be removed by co-precipitation with the naturally occurring iron which is found in groundwater. Tests showed that the removal rate was largely controlled by the arsenic concentration, the iron/arsenic ratio, and pH. Iron precipitation was induced by aeration and mixing through manual shaking.
Bench-scale tests demonstrated that up to 88% of the arsenic (III) in water could be removed by settlement over a period of 24 h. This was better than the removal rate achieved by filtration. It was found that the removal rate was mainly independent of the mode of mixing. For solid-liquid separation, draw-off arrangements were studied. It was found that the sample should be drawn off with a slow flowrate (<0.5 l/min). In such conditions the treated water quality is not seriously impaired for the particular design of the container which was examined.
From maps of the known distributions of arsenic, iron and pH, it was evident that 63% of the area in Bangladesh complied with the Bangladesh standard for arsenic. By interpreting the maps and applying the potential removal identified in the study, it was estimated that a further 9% of the area would comply with the Bangladesh standard, freeing 8 million people from arsenic contamination.     

下向焊焊接工艺在天然气管道建设中的应用

介绍了向焊焊接技术的发展，主要叙述了该工艺管道建设中的应用和主要特点。     

Comparison of mineral and soluble iron Fenton's catalysts for the treatment of trichloroethylene

Contaminant degradation, stoichiometry, and role of hydroxyl radicals (OH*) in four Fenton's systems were investigated using trichloroethylene (TCE) as a model contaminant. A standard Fenton's system, a modified soluble iron system with a pulse input of hydrogen peroxide, and two modified mineral-catalyzed systems (pH 3 and 7) were studied. In the standard Fenton's system, which had the most efficient reaction stoichiometry, 78% of the TCE was degraded; however, chloride analysis indicated that no more than two of the three chlorines were displaced per TCE molecule degraded. Although the modified soluble iron system was characterized by 91% TCE degradation, chloride analysis also indicated that no more than two of the chlorines were lost from the TCE. In the goethite system of pH 3, > 99% of the TCE was degraded. Near-complete release of chloride suggested that the TCE may have been mineralized. Only 22% degradation of TCE was achieved in the pH 7 goethite system. and there was minimal release of chloride. The mineral-catalyzed reactions exhibited the least efficient reaction stoichiometry of the four systems. Experiments using hydroxyl radical scavengers showed that the standard Fenton's system degraded TCE entirely by hydroxyl radical mechanisms, while approximately 10-15% of the degradation achieved in the modified soluble iron and goethite-catalyzed systems at pH 3 was mediated by non-hydroxyl radical mechanisms. In the goethite system at pH 7, only non-hydroxyl radical mechanisms were found. The goethite-catalyzed system at pH 3 effectively degraded the parent compound and may have the potential to mineralize contaminants when used for in situ soil and groundwater remediation and ex situ waste stream treatment in packed-bed reactors.     

部分城市自来水中典型无机金属元素的达标状况

针对当前给水管网中出现的无机金属元素超标问题,以36个城市的给水管网为研究对象,在不同时段采集龙头水并利用电感耦合等离子体质谱法对水样中常见无机金属元素进行检测分析,系统评价了现有市政管网中金属元素的达标状况和超标原因,并提出了相应的改善对策。结果表明,在调查范围内,铬、镍、镉、硒、铜和锌6种元素的含量均符合《生活饮用水卫生标准》(GB 5749—2006)。管网高峰水(早上08:30)中的铁、铅和铝以及初流水(凌晨05:30)中的铁超标率达到10%以上。除水源水的贡献外,龙头水中的无机金属含量主要受管材及其使用年限的影响。因此,在提高出厂水水质的基础上,建议通过优化管网运行管理、更换管材等方式控制无机金属元素的超标风险。     

DO对催化铁内电解预处理混合化工废水的影响

上海市西北某工业区排放的污水以化工和医药废水为主，其水量占排放总量的75％以上，属于典型的混合化工废水。目前该区的污水处理厂采用SBR工艺，但出水水质达不到有关的排放标准，尤其是色度超标严重。为此，开展了催化铁内电解法预处理该混合化工废水的生产性试验研究。结果表明，溶解氧浓度对预处理效果影响较大，在缺氧（DO〈0．5mg／L）条件下，对色度的去除效果较为明显，平均去除率可达42％，但对COD的平均去除率仅为14％左右；在高氧（DO=5．3～5．9mg／L）条件下，对COD的平均去除率可达44％左右，对色度的平均去除率为34％；在低氧（DO=0．9～1．4mg／L）条件下，对COD的平均去除率可达54．5％，对色度的平均去除率为43％，是比较理想的工况。     

阜新高岭土化学除铁增白研究

本文分析了辽宁阜新高岭土的化学组成和矿物组成,采用化学除铁方法对高岭土进行增白试验研究,产品白度达到橡胶填料、塑料填料的白度要求,符合国家标准的填料要求,该研究对高岭土化学除铁研究提供一定的参考。     

自然铁研究进展

自然铁在自然界的形成与保存都需要苛刻的条件,因此国内外关于自然铁的报道较少,国内对自然铁的研究更是比较薄弱,尚未形成统一的研究方法,也未形成分类标准及成因体系,因此在对自然铁的研究上往往出现会参照对比困难的情况。笔者通过大量阅读文献,回顾了自然铁的研究现状,并总结了其产状和成因类型。