水中钡的卫生标准的探讨

本文对有关水中钡的毒性和标准的文献进行了复习和讨论。对钡的毒性和标准意见不一。有认为钡高至250mg／1无不良影响，而有的认为10mg／1以上即有毒性。我们的试验电得到类似后者的结果。建议饮水中钡的卫生标准订为0．1mg／1。地面水中钡的最高容许浓度为1mg／1。     

Effect of barium sulfate modification on the SO2 tolerance of V2O5 /TiO2 catalyst for NH3-SCR reaction

Sulfur poisoning of V_2O_5/BaSO_4–TiO_2(VBT),V_2O_5/WO_3–TiO_2(VWT) and V_2O_5/BaSO_4–WO_3–TiO_2(VBWT) catalysts was performed in wet air at 350℃ for 3 hr,and activities for the selective catalytic reduction of NO_x with NH_3 were evaluated for 200–500℃.The VBT catalyst showed higher NO_x conversions after sulfur poisoning than the other two catalysts.The introduction of barium sulfate contributed to strong acid sites for the as-received catalyst,and eliminated the redox cycle of active vanadium oxide to some extent,which resulted in a certain loss of activity.Readily decomposable sulfate species formed on VBT-S instead of inactive sulfates on VWT-S.These decomposable sulfates increased the number of strong acid sites significantly.Some sulfate species escaped during catalyst preparation and barium sulfate was reproduced during sulfur poisoning,which protects vanadia from sulfur oxide attachment to a great extent.Consequently,the VBT catalyst exhibited the best resistance to sulfur poisoning.     

工业废水中钡的排放限值研究

在查阅大量文献资料基础上,总结了环境中钡的来源和特性,采用电感耦合等离子原子发射光谱方法测定地表水及稀土废水中的钡元素含量.对仪器的工作参数和被测元素的分析谱线进行了优化和选择,结合钡的化学毒性,提出了废水中钡的标准是5mg/L的建议.     

微波消解-火焰原子吸收分光光度法测定固体废物中的钡

采用微波消解法对固体废物浸出液样品进行前处理,采用乙炔-空气火焰原子吸收法测定钡的含量,检出限为2．04mg／L,加标回收率为94．5％,精密度为4．85％-6．81％。     

电导滴定法快速测定不同水中硫酸根的含量

采用电导法，用氯化钡标准溶液滴定水样中硫酸根的含量对测定结果的影响因素进行了探讨，本方法测定的回收率在９８￣１０２％之间，装置简单，试样测定时间仅需几分钟，准确度较高，适用范围广，如海水，卤水，自来水、深井水、雨水和部分工业废水等硫酸根含量的测定。     

氧弹燃烧-BaSO4重量法用于柴油中硫成分分析标准物质的定值

研究并确定了氧弹燃烧—BaSO4重量法测定柴油中硫含量的燃烧条件、吸收液种类、沉淀溶液pH、沉淀和转移条件等实验条件。在实验确定的优化条件下，该方法的定值结果与其他方法吻合良好。对定值结果进行了全面的不确定度评定，对于硫含量0．515％和1．027％的柴油中标准物质，获得的展伸不确定度分别为1.3％、1.4％(K=2)。利用该方法成功地实现了较低含硫量样品的定值。     

Use of multitracers for the study of water mixing in the Paraíba do Sul River estuary

Multitracers were used to study water mixing in the Paraíba do Sul River estuary region in August 2007 (dry season) and March 2008 (rainy season) and to evaluate the reach of the river plume in the direction of the open ocean. Two sampling campaigns were carried out, each in a different season. Based on these results, it was possible to conclude that the multitracers used in this study (salinity, Si, Ba and U, as well as the radium isotopes ²²³Ra, ²²⁴Ra, ²²⁶Ra and ²²⁸Ra) presented satisfactory results toward defining the plume reach and determining the residence time and water-mixing processes in the estuary. A strong correlation was observed between tracers and the distance to the coast. During the low river water discharge period, the riverine water took about 10 days to reach open ocean waters (salinity ∼ 35). During the rainy period this value decreased to 6 days. Based on the radium results, it was possible to calculate diffusion coefficients (K_h) of 23 km² d⁻¹ and 38 km² d⁻¹ for ²²⁴Ra and ²²³Ra, respectively, during the dry season (winter). Values of 65 km² d⁻¹ and 68 km² d⁻¹ for ²²³Ra and ²²⁴Ra, respectively, were found for the rainy period (summer).     

石墨炉原子吸收光谱法测定水中微量钡

通过一系列条件试验，研究了石墨炉原子吸收光谱法测定水中微量钡的石墨管类型、最佳加热程序和最佳基体改进剂等。本方法降低了背景吸收干扰，提高了灵敏度，改善了精密度，与其他方法比较，具有操作简便、快速、自动化程度高的特点，可用于水中微量钡的检测。     

氯化钡对水体生化自净过程影响的探讨

本文就不同浓度的钡对天然水的生化需氧过程、氨化及亚硝化过程的影响进行了探讨。发现大于5.00mg/l的钡在一定程度上抑制水体的生化需氧过程,增大钡离子的浓度,没有更有效地加强钡的抑制作用。同时,大于5.00mg/l的钡也对氨化和亚硝化过程产生影响,这种影响是通过降低这两个过程的反应速度来实现的。     

废旧泡沫塑料的回收再利用

以硫酸钡、聚异丁烯为线性混合成膜体系的填料和改性剂,经表面改性,制得具有较强防腐能力的复合型石英表面蚀刻保护涂料,通过正交实验设计确定了涂料组分配比和配制工艺.以载玻片为底材模拟蚀刻加工过程,进行了HF和NH4HF2混合酸(4∶1)的浸渍比检测,并考察了涂层的热稳定性.结果表明,线型混合体系中m(PS)(硬组分)和m(SBs)(软组分)质量比、w(改性剂)及w(填料)用量分别为1∶1,1.67%,2%,在60 ℃～80 ℃的浸渍温度下,浸渍比(W)为63.9,涂层可耐热到300℃,且对饱和氟化氢、氟化氢铵溶液等强腐蚀性介质有较好的化学稳定性.