我国生活饮用水中铅、砷检测能力验证分析

分析2012年由中国测试技术研究院承担的国家认监委能力验证项目"CNCA-12-A08生活饮用水中重金属及无机阴离子的检测"中铅、砷的能力验证结果,对生活饮用水中铅、砷检测方法进行比较和探讨。能力验证结果表明:ICP-MS法测定铅和砷的结果满意率最高,测定结果中位值及平均值与理论值最为接近。     

双道原子荧光光度计同时测定食品中砷和铅的方法研究

在食品检测中,砷和铅作为有害元素经常同时被作为食品中的必测卫生指标。按照国标检测,测定砷和铅反应介质不一致,砷和铅同时测定的矛盾一直困扰着人们。而本文通过反复试验,选择合适的条件,就可以同时测定砷和铅．避免了繁杂的重复性操作．节省了测定时间。该方法简便快速、稳定性好、适用性强、结果准确可靠。     

氢化物原子荧光光谱法同时测定生活饮用水中砷和硒

建立了氢化物发生原子荧光光谱法同时测定生活饮用水中砷和硒的方法.测试结果表明砷和硒在质量浓度分别为0.00μg/L~10.00μg/L和0.00μg/L~40.00μg/L范围内呈线性关系,相关系数分别为(砷r=0.9998,硒r=0.9997)。仪器检出限为砷:0.03μg/L硒:0.05μg/L。本方法检出限砷为0.075μg/L;硒为0.125μg/L。水质样品中砷的回收率为92.6%~96.5%,精密度为0.8%~1.4%;硒的回收率为91.2%~97.4%,精密度为1.0%~1.6%。应用本方法测定生活饮用水中的砷和硒方法简便、快速,结果准确可靠,较好地提高了工作效率。     

生活饮用水卫生质量检测的常见问题和解决策略

生活饮用水卫生质量关系到民众的用水安全,和人民生命健康息息相关。因此,相关部门需要对生活饮用水进行质量检测,然而现阶段我国饮用水卫生质量检测中还存在一定的问题,对检测结果准确性造成严重的影响。本文首先对我国饮用水安全现状进行分析,然后探讨生活饮用水卫生质量检测中存在的常见问题,最后提出有效的解决对策,希望能够给相关人员提供参考。     

生活饮用水和饮用水类饮料有何区别

《生活饮用水卫生标准》（GB 5749-2006）规定：生活饮用水是指供人生活的饮水和生活用水。通俗地说生活饮用水是指全人类都能喝的水,不分种族、不分性别、不分年龄、不分疾病与健康,不分时间与空间,长年累月都能喝的水,这种水就是各国政府都规定了其标准的＂生活饮用水＂,也就是俗称的＂自来水＂。     

能量色散X射线荧光光谱法在检测仿真饰品中有害元素的应用

用能量色散X射线荧光光谱法快速定性仿真饰品中的铅、镉、铬、砷、汞的研究。检测仿真饰品中铅、镉、铬、砷、汞的含量来判定其是否符合要求。对于定性与定量的测试进行了能量色散X射线荧光光谱法与电感耦合等离子发射光谱法的比较分析,证实了结果可靠。     

银餐具中砷、镉、铅迁移量的测定

本文采用HPLC-ICP-MS对银勺进行砷、镉、铅迁移量的测试。测试结果表明在中性实验条件下,砷、镉、铅均未检出。在酸性实验条件下,检测出了微量的铅元素。对所用银勺进行杂质元素含量测试,结果表明其中含有一定量的锑和铅元素。银餐具的安全性,应引起商家和检测机构的足够重视。     

水中铅和镉含量的测定能力验证分析

通过能力验证计划,了解我国检验检测机构对水中铅和镉含量检测项目的检测能力。采用单因素方差分析法(F检验法),对能力验证样品进行均匀性检验,用稳健统计技术处理,z比分数评判各参加者的检测结果。结果表明,参加的12家检验检测机构的23个检测结果中,满意结果20个(占86.96%)、有问题结果2个(占8.70%)、不满意结果1个(占4.35%),共有9家检验检测机构的检测结果全部满意,占参加者总数的75%。     

高砷粗铅真空蒸馏脱除砷的研究

采用鼓风炉熔炼高砷粗铅为原料,对其真空蒸馏脱除砷进行理论分析和实验研究,考察蒸馏温度、恒温时间对砷脱除率、金属铅直收率的影响。理论分析结果表明:砷与铅的饱和蒸气压差异较大,且两者不形成金属间化合物,在较低的蒸馏温度条件下,高砷粗铅真空蒸馏可以有效地脱除砷。实验结果表明:在系统压力为5~15 Pa,蒸馏温度为973 K,蒸馏时间为30 min的条件下,砷的脱除率为80%,铅的直收率为97%,粗铅中铜的存在对砷的脱除有较大的影响。此工艺为粗铅真空蒸馏脱除砷提供新的方法,对粗铅采用真空蒸馏精炼除砷具有一定的指导意义和应用价值。     

日本神户制钢推出可高效去除污水中砷元素的铁粉

神户制钢所开发成功可高效率吸附和净化砷（As）元素的铁粉，并将推出相应的商品。铁粉以净化工厂污水、温泉废水以及地下水等为目的，只需让受到砷污染的水连续流过装有铁粉的容器，即可将砷浓度降至环境标准值（饮用水标准值）0．01mg／L以下。与以前的砷吸附剂相比，具有其2倍以上的吸附力。不仅可用于砷，还可用于铅（Pb）、镉（Cd）以及硒（Se）等重金属的净化。     

PZT压电厚膜用PT过渡层的制备及表征

用溶胶-凝胶法在Pt（111）／Cr／SiO2／Si衬底上制备了（100）取向PT过渡层,探讨了制备工艺条件对胛过渡层成膜情况的影响,结果表明,快速热处理工艺制备的PT过渡层结晶较好,而热解时间过长和退火时间过长都会引起铅的损失,造成TiO杂相的出现,从而对PT过渡层的结晶产生不利影响。     

Surface complexation modeling of the removal of arsenic from ion-exchange waste brines with ferric chloride

Brine disposal is a serious challenge of arsenic (V) removal from drinking water using ion-exchange (IX). Although arsenic removal with ferric chloride (FeCl(3)) from drinking waters is well documented, the application of FeCl(3) to remove arsenic (V) from brines has not been thoroughly investigated. In contrast to drinking water, IX brines contain high ionic strength, high alkalinity, and high arsenic concentrations; these factors are known to influence arsenic removal by FeCl(3). Surface complexation modeling and experimental coagulation tests were performed to investigate the influence of ionic strength, pH, Fe/As molar ratios, and alkalinity on the removal of arsenic from IX brines. The model prediction was in good agreement with the experimental data. Optimum pH range was found to be between 4.5 and 6.5. The arsenic removal efficiency slightly improved with higher ionic strength. The Fe/As ratios needed to treat brines were significantly lower than those used to treat drinking waters. For arsenic (V) concentrations typical in IX brines, Fe/As molar ratios varying from 1.3 to 1.7 were needed. Sludge solid concentrations varying from 2 to 18 mg L(-1) were found. The results of this research have direct application to the treatment of residual wastes brines containing arsenic.     

Perspectives of low cost arsenic remediation of drinking water in Pakistan and other countries

Arsenic concentrations above acceptable standards for drinking water have been detected in many countries and this should therefore is a global issue. The presence of arsenic in subsurface aquifers and drinking water systems is a potentially serious human health hazard. The current population growth in Pakistan and other developing countries will have direct bearing on the water sector for meeting the domestic, industrial and agricultural needs. Pakistan is about to exhaust its available water resources and is on the verge of becoming a water deficit country. Water pollution is a serious menace in Pakistan, as almost 70% of its surface waters as well as its groundwater reserves have contaminated by biological, organic and inorganic pollutants. In some areas of Pakistan, a number of shallow aquifers and tube wells are contaminated with arsenic at levels which are above the recommended USEPA arsenic level of 10 ppb (10 μg L⁻¹). Adverse health effects including human mortality from drinking water are well documented and can be attributed to arsenic contamination. The present paper reviews appropriate and low cost methods for the elimination of arsenic from drinking waters. It is recommended that a combination of low cost chemical treatment like ion exchange, filtration and adsorption along with bioremediation may be useful option for arsenic removal from drinking water.     

工艺冷却冰水分段冷却节能技术应用

本文结合啤酒冷冻站工艺,介绍大连冷冻机股份有限公司研发的工艺冷却冰水分段冷却技术,配套高蒸发温度的内容积比可调的螺杆压缩机组,将第一段冷却蒸发温度提高至＋10℃蒸发,在不增加压缩机功耗前提下,制冷量提高了50％。分段冷却后,总体能效比提高了25％以上。冰水分段冷却技术推广应用,不仅提高能效比,还可以降低制冷系统整体投资,达到节能减排的目的,是值得推广的实用新技术。     

A combined treatment approach using Fenton's reagent and zero valent iron for the removal of arsenic from drinking water

Studies on the development of an arsenic remediation approach using Fenton's reagent (H2O2 and Fe(II)) followed by passage through zero valent iron is reported. The efficiency of the process was investigated under various operating conditions. Potable municipal water and ground water samples spiked with arsenic(III) and (V) were used in the investigations. The arsenic content was determined by ICP-QMS. A HPLC-ICPMS procedure was used for the speciation and determination of both As(III) and (V) in the processed samples, to study the effectiveness of the oxidation step and the subsequent removal of the arsenic.The optimisation studies indicate that addition of 100 microl of H2O2 and 100 mg of Fe(II) (as ferrous ammonium sulphate) per litre of water for initial treatment followed by passing through zero valent iron, after a reaction time of 10 min, is capable of removing arsenic to lower than the US Environmental Protection Agency (EPA) guideline value of 10 microg/l, from a starting concentration of 2 mg/l of As(III). Using these suggested amounts, several experiments were carried out at different concentrations of As(III). Residual hydrogen peroxide in the processed samples can be eliminated by subsequent chlorination, making the water, thus, processed, suitable for drinking purposes. This approach is simple and cost effective for use at community levels.     

两种DXA骨密度体模比较研究

研究比较国产QC-2型腰椎骨密度体模(以下称QC-2体模)和欧洲脊椎骨密度体模(以下称ESP体模)在双能X射线全身骨密度仪(以下称DXA)检定中的差异性。用DXA仪器对这两种体模分别进行检测,对测量结果进行比较分析。(1)QC-2型体模和ESP型体分别被仪器进行测量时,仪器测量的BMD同两个体模的BMD相比,误差分别在-15.1%~11.5%和-16.1%~12.5%之间;而且,两个体模的各自标称值与相应的仪器测量值之间,分别都有非常好的线性关系,r0.99。(2)用回归方程进行校正后,仪器值(BMD)与两个体模的各自的标称值之间的误差分别在-3.8%~4.4%和在-3.8%~4.4%之间。用成对样本均数比较方法,对校正结果进行统计分析,经配对t检验,二者结果没有显著差异(P0.05)。表明这两种腰椎骨密度体模都能用于双能X射线全身骨密度仪(DXA)的检定。     

微波消解-原子荧光光谱法测定中药中的砷和硒

建立了微波消解-原子荧光光谱测定中药中砷和硒含量的方法。该方法测定砷和硒的检出限分别为0.087μg/L和0.123μg/L,荧光强度与砷及硒的质量浓度在0~200μg/L及0~100μg/L范围内呈线性关系。用于中药中砷和硒的测定,相对标准偏差(n=6)均小于3.6%,砷的回收率在95.2%~102.8%之间,硒的回收率在94.5%~104.8%之间。     

超重力法-醇水体系合成纳米钇铝石榴石

以NH4HCO3和NH3·H20为沉淀剂,醇水体系为溶剂,合成了钇铝石榴石（YAG）粉体,考察了超重力场和不同醇体积分数（R）对合成YAG粉体的影响,利用X射线衍射fXRD）、热重一差示扫描同步热分析（TG—DSC）和扫描电镜（SEM）等手段对粉体进行了研究,结果表明,超重力场中制备的YAG粉末颗粒更细小,分布范围更窄,分散性更好;醇水体系作为溶剂更有利于制备分散性好,粒径小的纯相YAG粉体;最适的醇体积分数为30％-50％。当以NH4HCO3和NH3·H3O为沉淀剂,R=30％的醇水体系为溶剂,在超重力场中合成的YAG前躯体在1000℃下煅烧2h,获得了分散性好、分布范围窄、晶型完整、平均粒径约为50nm的球形YAG粉体。     

某分布式能源系统中冷热电三联产控制优化分析

对于分布式能源系统中冷热电三联产项目,面临冷热电需求之间不平衡的矛盾。本文在传统的以电定热（冷）和以热（冷）定电两种运行方式的基础上,提出通过优化控制逻辑、智能化预估算控制、优化运行方式和添加辅助设备等方式,对分布式能源系统中冷热电三联产进行了优化,并实际运用在某产业园分布式能源项目中,通过对优化前、后联产系统的总热效率进行的计算对比,验证了该方法的合理性,对同类型项目有很好的借鉴意义。