单柱离子色谱法测定碱金属和碱土金属

本文介绍用ZIC-ⅡA型离子色谱仪测定碱金属和碱土金属,及其离子色谱性能.     

离子色谱法中高浓度盐基体对无机阴离子分析影响规律的研究

本文首次研究高浓度盐基体中，大量盐的存在对无机阴离子的保留时间，峰高峰面积等参数的影响规律，并对其影响机理进行了初步探讨，实验证明，在样品中离子总浓度不超过柱容量孤情况下，虽然由于某些离子的浓度过高，使待测离子的保留时间变短，峰形改变，但用峰面积和标准加入外推法计算，仍可得到较即的结果。     

H13钢表面多弧离子镀CrAlN涂层的显微硬度及耐磨性影响

目的 提高H13热作模具钢表面的显微硬度及耐磨性。方法 通过多弧离子镀技术,分别对未经热处理的H13钢、淬火H13钢以及氮化H13钢的表面进行多弧离子镀沉积CrAlN涂层,并分别对这3种基体上的CrAlN涂层的显微硬度和摩擦磨损性能进行研究。结果 涂层表面均较为平整,且出现了白色小颗粒。经过淬火和氮化处理后,H13钢CrAlN涂层的显微硬度达到3 300HV以上,达到基体的14倍多。与基体的摩擦系数相比,淬火和氮化处理后,H13钢的摩擦系数比基体低,镀膜后的摩擦系数比基体高。氮化H13钢表面CrAlN涂层的磨损机理主要是磨粒磨损和黏着磨损共同作用,淬火H13钢的CrAlN涂层磨损机理主要是黏着磨损;淬火和氮化后H13钢基体上CrAlN涂层的耐磨性均得到较大的提高。     

硫杂冠醚的合成及其对废水中Ag(I)的选择性萃取研究

针对当前含银废液综合回收利用率低,以及不当排放造成严重环境污染等问题.本研究以邻苯二酚为原料,经亲核取代、酰氯酰化、缩合反应制得一种全新结构硫杂冠醚7,10-二硫杂苯并-18-冠-6(硫杂冠醚3,Thia18C6),产物经核磁共振氢谱(~1H NMR)、X-射线衍射单晶进行了结构表征,进而采用溶剂萃取的方法考察了其对不同金属离子的选择性萃取能力.结果表明,在单一体系下,Thia18C6对银离子表现出较为优异的萃取能力,萃取率可达97.68%,而在多种杂质离子(Cu~(2+)、Pb~(2+)、Zn~(2+)和Ni~(2+))共存的复杂体系中,Thia18C6对银离子表现出了较强的选择性.     

氯化铜催化二噁英生成实验及指纹特性分析

氯化铜被认为是对二■英(PCDD/F)生成促进作用最强的金属催化剂,温度和氧气含量是影响其催化二■英生成的关键因素.本文选取250～550℃间8个不同温度点及0～20%间4种不同氧气含量,系统性地研究了温度和氧气含量对含氯化铜模拟飞灰(MFA)生成二■英的影响,并通过分析指纹特性探讨二■英的生成路径和机理.结果发现,290～350℃之间二■英生成量较高,且在290℃时二■英总量达到最大值;氧气含量为10%时二■英生成量达到最高.研究二■英同分异构体分布可从分子层面为研究其生成路径和机理提供重要信息,因此,本文分析了四至八氯代PCDD/F的全部异构体的分布.结果表明,在本文所选取的温度和氧含量范围内,温度对二■英生成路径的影响高于氧气含量.最后,重点讨论了2,3,7,8位氯取代的17种有毒异构体的分布随温度和氧气的变化情况及生成路径.利用主成分分析法(PCA)证实了氯化铜催化二■英从头合成过程中存在经由氯酚路径生成的异构体,并讨论了不同工况下氯酚路径对二■英生成的影响.     

Effect of precipitation pH and coexisting magnesium ion on phosphate adsorption onto hydrous zirconium oxide

To understand the effect of precipitation pH and coexisting Mg~(2+) on phosphate adsorption onto zirconium oxide(ZrO_2), ZrO_2 particles precipitated at pH 5.3, 7.1 and 10.5, i.e., ZrO_2(5.3), ZrO_2(7.1)and ZrO_2(10.5), respectively were prepared and characterized, then their adsorption performance and mechanism in the absence and presence of Mg~(2+) were comparatively investigated in this study. The results showed that the Elovich, pseudo-second-order and Langmuir isotherm models correlated with the experimental data well. The adsorption mechanism involved the complexation between phosphate and zirconium. Coexisting Mg~(2+) slightly inhibited the adsorption of phosphate on ZrO_2(5.3), including the adsorption capacity and rate, but coexisting Mg~(2+) greatly increased the adsorption capacity and rate for ZrO_2(7.1)and ZrO_2(10.5). The enhanced adsorption of phosphate on ZrO_2(7.1) and ZrO_2(10.5) in the presence of Mg~(2+) was mainly due to the formation of Mg~(2+)-HPO_4~(2-) ion pair(MgHPO_4~0) in the solution and then the adsorption of MgHPO_4~0 on the adsorbent surface, forming the phosphatebridged ternary complex Zr(OPO_3H)Mg. In the absence of Mg~(2+) , the maximum phosphate adsorption capacity at pH 7 calculated from the Langmuir isotherm model decreased in the order of ZrO 2(7.1)(67.3 mg/g) ZrO_2(5.3)(53.6 mg/g) ≈ ZrO_2(10.5)(53.1 mg/g), but it followed the order of Zr O2(7.1)(97.0 mg/g) ZrO_2(10.5)(79.7 mg/g) ZrO_2(5.3)(51.3 mg/g) in the presence of Mg~(2+) . The results of this work suggest that ZrO_2(7.1) is more suitable for use as an adsorbent for the effective removal of phosphate from municipal wastewater than ZrO_2(5.3) and ZrO_2(10.5),because Mg~(2+) is generally present in this wastewater.     

气力输送化工粉体静电带电影响因素试验研究

采用自建全尺寸粉体静电试验系统,以聚丙烯颗粒为试验介质物料,测试了气力输送过程中物料质量流量、输送气体流量以及离子风消电器对聚丙烯颗粒静电带电量的影响规律。结果表明:气力输送粉体物料时,粉体颗粒与管壁碰撞是影响颗粒带电的主要因素之一,导致颗粒带电量随颗粒质量流量降低和气体输送流量增加(风速增大)而增大。提高质量流量、降低输送气体流量并使用离子风静电消除器,是降低气力输送物料静电危害风险的重要措施。     

船舶电池储能系统管理策略研究

目的 降低船舶污染排放,延长电池使用寿命,改善变工况条件下储能系统的动力性.方法 电池系统采用基于经验模态分解及模糊控制的双层管理策略,以磷酸铁锂电池组为主动力源来承担平缓功率,超级电容组为辅动力源来承担高频功率,引入样本熵对功率信号进行评估.结果 以某船舶工况进行仿真,相较于单一经验模态策略,引入模糊修正策略后的磷酸铁锂电池组放电深度由6.55％～94.35％变为14.56％～57.15％;超级电容组的放电深度由14.83％～52.11％变为12.7％～79.38％;磷酸铁锂电池组功率信号样本熵值由0.0182降为0.0177.结论 变工况条件下,上述控制策略可降低单工况下柴油机平均燃油消耗,减少储能端电池受到暂态功率的冲击,延缓电池老化速度,加长电池使用寿命,提升船舶储能系统的可靠性及环保性.     

Insights into measurements of water-soluble ions in PM2.5 and their gaseous precursors in Beijing

To better understand the characteristics and transformation mechanisms of secondary inorganic aerosols, hourly mass concentrations of water-soluble inorganic ions (WSIIs) in PM_2.5 and their gaseous precursors were measured online from 2016 to 2018 at an urban site in Beijing. Seasonal and diurnal variations in water-soluble ions and gaseous precursors were discussed and their gas-particle conversion and partitioning were also examined, some related parameters were characterized. The (TNH₃) _Rich was also defined to describe the variations of the excess NH₃ in different seasons. In addition, a sensitivity test was carried out by using ISORROPIA II to outline the driving factors of gas-particle partitioning. In Beijing, the relative contribution of nitrate to PM_2.5 has increased markedly in recent years, especially under polluted conditions. In the four seasons, only a small portion of NO₂ in the atmosphere was converted into total nitrate (TNO₃)_, and more than 80% of TNO₃ occurred in the form of nitrate due to the abundant ammonia. The concentration of total ammonia (TNH₃) was much higher than that required to neutralize acid gases, and most of the TNH₃ occurred as gaseous NH₃. The nitrous acid (HONO) concentration was highly correlated with NH₃ concentration and had increased significantly in Beijing compared with previous studies. The total chloride (TCl) was the highest in winter, and ε(Cl^?) was more sensitive to variations in the ambient temperature (T) and relative humidity (RH) than ε(NO₃^?).     

南京北郊四季PM2.5中有机胺的污染特征及来源解析

2017年12月至2018年11月在南京北郊采集了大气PM_(2.5)样品,对其中的有机胺、主要水溶性离子、有机碳和元素碳进行了定量分析.共测定南京北郊大气PM_(2.5)中5种有机胺:甲胺、乙胺、二甲胺、三甲胺和苯胺.有机胺年平均总浓度为(54. 2±29. 2) ng·m~(-3),其中最丰富的物种为二甲胺[年均值:(20. 2±13. 7) ng·m~(-3)],其次为甲胺[年均值:(13. 1±6. 3)ng·m~(-3)]、三甲胺[年均值:(8. 6±4. 1) ng·m~(-3)]、乙胺[年均值:(6. 3±4. 1) ng·m~(-3)]和苯胺[年均值:(5. 9±3. 9) ng·m~(-3)],有机胺总浓度呈现出明显的季节变化,表现为夏季秋季春季冬季.污染天有机胺的浓度大于清洁天,主要是受大气颗粒物酸性影响大气有机胺气/粒转换所致,并且大气颗粒物酸性也是导致夏季高温条件下颗粒态有机胺仍高于其它季节的另一原因.在新粒子生长天,发现有机胺的浓度会有所增加. PMF法溯源结果显示南京北郊大气PM_(2.5)中主要有6种有机胺排放源:即工业源、农业源、生物质燃烧、机动车排放、二次源和道路扬尘.其中甲胺、乙胺主要来源于二次源和机动车排放;二甲胺、三甲胺主要来源于生物质燃烧、二次源和机动车排放;苯胺主要来源于工业排放和生物质燃烧.有机胺的来源具有显著的季节差异,春季秋季道路扬尘源占比较高,夏季二次源为有机胺主要的污染源,冬季机动车排放源和生物质燃烧源有一定提升.而有机胺的昼夜差异并不明显,二次源、机动车排放源以及生物质燃烧源是3个主要影响因素.