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研究了砂浆的碱度和AgNO3溶液指示剂的浓度对测量砂浆变色边界Cl-浓度的影响。将AgNO3,NaOH及NaCl 3种物质混合,发现溶液中生成的沉淀反应产物中的AgCl的质量分数随溶液中OH-浓度的增加而减少、沉淀反应产物的颜色随AgCl的含量而变化。用0.100mol/L和0.035mol/L的AgNO3指示剂喷洒到按北欧标准NTBuild492进行电迁移试验之后的砂浆试件上,并测试试件变色边界Cl-浓度,结果表明:0.035mol/L的AgNO3指示剂比用0.100mol/L的AgNO3指示剂测试试件变色边界的Cl-浓度小,因此,0.035mol/L的AgNO3指示剂检测到的变色深度大些;变色边界处的Cl-浓度随砂浆的pH值升高而增大。
Abstract：The effects of alkali of the mortar specimens and the concentrations of AgNO3 solution indicator on the Cl-concentration at the color change boundary of the specimens were investigated.When AgNO3,NaOH and NaCl solutions were mixed,the mass fraction of AgCl in the precipitated products decreased as the OH-concentration increased and the color of the precipitated products changed with the mass fraction of AgCl.Different mortar specimens after the NT Build492 testing were sprayed with 0.100 mol/L and 0.035 mol/L AgNO3 solutions respectively.The color depth change and the Cl-concentrations at the color change boundary were also measured.Compared with the use of 0.100 mol/L AgNO3 solution,the Cl-concentration at the boundary was lower and thus the color depth change was greater when 0.035 mol/L AgNO3 was used.The Cl-concentration at the color change boundary increased as the pH value of the mortar specimens was increased.
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基本信息:
中图分类号:TU528
引用信息:
[1]何富强,史才军,元强,等.硝酸银显色法变色边界处氯离子浓度的影响因素[J].硅酸盐学报,2008,No.231(07):890-895.
2008-07-15
2008-07-15