检索结果-南通市图书馆

Chemical Investigation of Potassium Methyl Siliconate as Deacidification and Strengthening Agent for Preservation of Aged Papers

引用

Chinese Journal of Polymer Science 2015年第12期33卷 1672-1682页

作者： Shu-juan Zhang 张小岗 Wen-ting Shang Department of Chemistry Renmin University of China

Potassium methyl siliconate （PMS） was investigated as a simple physicochemical modification in aged paper using silane coupling technique. The PMS-based solution was shown to favor penetration in the cellulose fibers on the paper with suitable uptakes being achieved at low concentrations. The studies of the physicochemical properties of the treated paper （mechanical strength and alkalinity） demonstrated that, besides the required deacidification feature and high level of alkali reserves, the immersion treatment by PMS allowed the enhancement of the mechanical intensities of paper arising from the interaction between Si--OH generated in hydrolysis of PMS and C--OH of cellulose on the paper. Adding ethanol into PMS solution could significantly improve mechanical properties of the aged paper treated by the formula apart from modifying the flatness of the paper. Optimized treatment process was achieved by altering the ratio of ethanol to water in PMS-based solutions. Contact angle measurements indicated the occurrence of hydrophobic character of the papers in immersion treatment with PMS-based solutions. The easy availability of the materials and simplicity of the method rendered it convenient for treatment for aged paper documents.

关键词： Potassium methyl siliconate Paper Deacidification Reinforcement ageing.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of Temperature, Water Quality and Collector Type on Flotation Performance of a Peruvian Phosphate Ore

引用

Journal of Chemistry and Chemical Engineering 2013年第4期7卷 351-355页

作者： Rogerio de Oliveira Baldomo Marisa Martins Marcus Vinicius Turibio Rodrigues Laurindo de SallesLeal Filho Vale Fertilizantes Technology and Processing Department Belo Horizonte-MG 30150-904 Brazil Mineral Processing Research Group Engineering School University of Sao Paulo Sao Paulo 05508-900 Brazil

The sedimentary phosphate deposit of Bayovar is located in a very dry area of Peru （desert of Sechura） which is close to the Pacific coast. It consists of seven superposed layers （beds） which call for different strategy of concentration. The ore is composed predominantly by apatite （84% in weight basis） plus silicates （16%）. To concentrate phosphate from beds 6-7, it is necessary to carry out further cationic reverse flotation of silicates, at neutral pH, to yield a concentrate which meets market specification. The new process was developed in laboratory scale by a collaborative program conducted between Vale S. A. and the University of Sao Paulo--Brazil. As water resources are very limited at Bayovar region, all the steps of concentration, including flotation, must be performed with seawater which must be continuously recycled. This work addresses some relevant topics related to the use of seawater in the reverse cationic flotation of silicates： influence of temperature, water quality （ageing.and chemical composition） and collector type. The results indicate that amido amine works better than ether amine. If flotation is conducted with the former collector, the separation process is able to tolerate changes in temperature （25 ℃-40 ℃） and water quality caused by either evaporation or ageing.

关键词： Phosphate flotation seawater temperature ageing.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：