利用氨吸附漫反射红外光谱法探测蒙脱石的固体酸性     

刘冬  袁鹏  刘红梅  蔡进功  覃宗华  樊明德  陶奇  何宏平  朱建喜 《矿物学报》2010,30(1)

用氨吸附漫反射红外光谱学方法,借助图谱拟合解谱手段,探测了不同预处理温度下蒙脱石表面酸性变化特征,并分析了其变化原因。结果表明,低温热处理后的蒙脱石,其B酸和L酸量增大;经较高温度(400、600℃)煅烧的样品,层间距急剧减小,氨分子难以进入层间与酸位发生反应,可探测到的两种酸量都将减少。  相似文献   

北京地区中元古代与中生代火山岩的酸度、系列、构造环境及岩浆成因   总被引：13，自引：4，他引：9  

邱家骧  廖群安 《岩石矿物学杂志》1998,17(2):104-117

本文对北京地区中元古代及中生代火山岩的地质学、岩石学、矿物化学、地球化学、岩石成因学及构造环境学进行了综合研究。对火山岩的时空分布及成分变化进行了论述,对酸度频率及岩浆系列进行了分析,对构造环境及拉张距离进行了估算,对岩浆的来源及演化机理进行了探讨。  相似文献   

Multiphase chemistry and acidity of clouds at Kleiner Feldberg     

S. Fuzzi  M. C. Facchini  D. Schell  W. Wobrock  P. Winkler  B. G. Arends  M. Kessel  J. J. Möls  S. Pahl  T. Schneider  A. Berner  I. Solly  C. Kruisz  M. Kalina  H. Fierlinger  A. Hallberg  P. Vitali  L. Santoli  G. Tigli 《Journal of Atmospheric Chemistry》1994,19(1-2):87-106

The chemistry of cloud multiphase systems was studied within the Kleiner Feldberg Cloud Experiment 1990. The clouds encountered during this experimental campaign could be divided into two categories according to the origin of air masses in which the clouds formed. From the chemical point of view, clouds passing the sampling site during the first period of the campaign (26 October-4 November) were characterized by lower pollutant loading and higher pH, as compared to clouds during the final period of the experimental campaign (10–13 November). The study of multiphase partitioning of the main chemical constituents of the cloud systems and of atmospheric acidity within the multiphase systems themselves (gas + interstitial aerosol + liquid droplets) are presented in this paper. A general lack of gaseous NH₃ was found in these cloud systems, which caused a lack of buffer capacity toward acid addition. Evidence supports the hypothesis that the higher acidity of the cloud systems during this final period of the campaign was due to input of HNO₃. Our measurements, however, could not determine whether the observed input was due to scavenging of gaseous HNO₃ from the air feeding into the cloud, or to heterogeneous HNO₃ formation via NO₂ oxidation by O₃ to NO₃ and N₂O₅. Sulfate in cloud droplets mainly originated from aerosol SO ₄ ^2– scavenging, since S(IV) to S(VI) liquid phase conversion was inhibited due to both lack of H₂O₂ and low pH of cloud droplets, which made O₃ and metal catalyzed S(IV) oxidation inefficient.  相似文献   

草酸钾法测定铀水冶浸出液中余酸的研究及应用     

龚治湘  罗明标  宋金如  蒋小良  周仁华 《华东地质学院学报》2005,28(1):83-86

研究了用草酸钾为掩蔽剂的K2C2O4 MgCl2 法测定浸出液中剩余酸度,比(NaPO3 )6 法及EDTA Ca法优越,本法对铀、铁、铝、钼等干扰离子掩蔽能力强,掩蔽效果好,测得的余酸量为真实的硫酸含量.在现场运行11d24h跟班取样, 拟定余酸工艺参数7. 0±2g/L,在生产上运行四个月铀的浸出率月平均值大于93%,硫酸消耗降低,生产成本下降,从而解决了铀水冶工艺长期存在的一个难题.  相似文献   

Performance of alkaline reactive materials in the remediation of acidic groundwater     

Alexandra N. Golab Buddhima Indraratna Mark A. Peterson 《中国地球化学学报》2006,25(B08):88-89

Acidic groundwater and surface water are common problems in coastal Australia causing massive fish kills, attack of concrete and steel structures, and clogging of waterways. The best solution is the construction of a permeable reactive barrier （PRB） to neutralise the acidic groundwater before entering nearby waterways. A PRB consists of a trench filled with reactive material that intersects the flow-path of a contaminant plume and ameliorates the contaminated groundwater. A PRB is being designed in a pilot scale study in ASS in southeastern Australia. The groundwater is acidic （pH 3） with high A1 （40 mg/L） and Fe （530 mg/L） levels. When the acidic groundwater comes into contact with this PRB, the acid will be neutralized by the alkaline reactive materials and the aluminum and iron will be removed from the groundwater. Twenty-five alkaline materials were tested for use in the PRB, with an emphasis on waste materials, including oyster shells and recycled concrete. Batch tests were used to select the best two reactive materials for use in the column tests. The pH achieved by each material was controlled by the reaction kinetics of the dominant alkaline component.  相似文献   

Comparison of binding abilities of fulvic and humic acids extracted from recent marine sediments with UO₂     

C. Munier-Lamy  Ph. Adrian  J. Berthelin  J. Rouiller 《Organic Geochemistry》1986,9(6)

Potentiometric titrations were used to measure conditional stability constants of UO₂²⁺-fulvic acid and UO₂²⁺-humic acid complexes. Both 2:1 and 1:1 COO^-:UO₂²⁺ binding were observed. With decreasing metal concentration (2.5·10⁻⁴-6.25·10⁻⁵ M) increasing amounts of UO₂²⁺ were in the form of 1:1 humate complexes and 2:1 fulvate complexes. Despite the high nitrogen content and the low acidic OH group content, the successive stability constant values were similar to those determined for divalent cations associated with fulvic and humic compounds isolated from soils. Stability constant values increase simultaneously with increasing ionization of the humic (or fulvic) acid polyelectrolytes and with decreasing metal concentration.  相似文献   

省级酸度检定数据处理系统     

温晓辉 《内蒙古气象》2014,(6):29-30

针对目前各省酸度计量检定工作存在的自动化程度低的情况,提出了采用VB 6.0可视化编程语言和ACCESS数据库等技术,开发了省级酸度检定数据处理系统。经过一年时间的试运行,该系统实现了对送检的酸度设备检定后,数据自动处理、保存、打印电子证书、原始记录查询和证书查询等功能。为今后全面开展酸度检定工作做好准备,提高数据准确率和检定工作效率。  相似文献