酮类化合物在含氟和非含氟整体柱上电色谱保留行为比较

利用全氟辛基甲基丙烯酸酯为单体之一,通过原位聚合的方式,制备了1种新型的含氟有机聚合物毛细管电色谱整体柱,并在相同的实验条件下对几种酮类化合物在含氟和非含氟有机聚合物整体柱上的保留行为进行了比较.结果表明,在含氟有机聚合物整体柱上,酮类化合物的保留能力明显减弱,选择性也有所提高.     

APPLICATION OF CATIONIC POLYMERIC MICROPARTICLES ON RETENTION AND DRAINAGE

1.INTRODUCTIONThe microparticles retention and drainage technologywas brought in 1980s. It brings striking effect whenused in wet-end in paper-making. The retention offines and fillings and the drainage of pulp improved alot, meanwhile, the evenness also improved. So, mi-croparticles retention and drainage system is the maindeveloping direction of retention and drainage aids on paper-making industry.All microparticles in microparticle system we use currently are inorganic anionic. It rea…     

REFINING BEHAVIOUR OF BAMBOO LONG FIBRE FRACTION PULP

The strength properties of a sheet of paper depend on the original qualities and strength of the fibres and to the extent of bonding between the fibres that make up the sheet. A paper sheet made from virgin pulp without beating/refining is characterized by low strength, bulkiness and rough surface. These undesirable characteristics can be changed to a large extent by treating the pulp mechanically. This mechanical treatment of fibres in water is termed beating/refining. The refining of any fib…     

STDUY ON RETENTION AND DRAINAGE PROPERTIES OF THE HIGH SUBSTITUTED DEGREE CATIONIC STARCH

1.INTRODUCTIONCationic starch, due to having some positive charges, is getting widespread use in papermaking industry. Itcan be used as aids for strengthening, retention, anddrainage in the wet end of paper machine based on itsdegree of substitution. In general the degree ofsubstitution (DS) of the cationic starch is ranged from0.01 to 0.07. In order to further develop the use ofcationic starch in papermaking industry, we try toprepare the high substituted degree cationic starch(HCS). …     

GC/MS及保留指数法测定底泥中的多环芳烃

对苏州河底泥样品采用正己烷∶丙酮（１∶１）索氏提取，萃取液经浓缩分段后加入内标物萘、菲、艹屈，测定并计算各多环芳烃保留指数，结合ＧＣ／ＭＳ法，从该底质中鉴别出４５种多环芳烃及同分异构体．多环芳烃保留指数与文献相符     

药用皖鄂鼠尾草精油成分的初步分析

以同时蒸馏萃取法提取了药用皖鄂鼠用草精油，用毛细管ＧＣ／ＭＳ／ＤＳ联用仪分离并初步鉴定了其中的３５种化合物，占总峰面积的８７％的再用气相色谱－傅里叶红外光谱联用技术、双柱程序升温保留指数和标样核对等方法鉴定了１９种化合物，占总峰面积２５％。     

多元参数相关法预测气相色谱保留值

利用数理统计方法研究了诱导效应指数Ｉ，摩尔折射度ＲＤ，疏水亲脂参 数１ｇｐ以及分子联通性指数１ｘ与气相色谱保留行为的关系。探讨了它们对脂 肪醇、醛、酸、胺及脂肪酸酯色谱保留值的不同贡献。利用得到的相关方程，实 现了对色谱保留值的预测。结果表明，四元相关的预测精度明显高于二元和 二元。     

多元酚类的高效液相色谱分离及其测定

本文利用反相高效液相色谱对原儿茶酸、原儿茶醛、d—儿茶素、没食子酸、对羟基苯甲酸五种化合物进行分离和定量测定。并着重研究流动相酸度不同时对上述物质的容量因子、保留时间和分离度的变化情况。     

从获取客户到维系客户的方法研究

研究了客户获取和客户维系的关系问题，提出了一种新的观点和模型方法，该模型把获取客户作为研究客户生命周期的条件，从而建立起客户获取与客户维系的直接联系，与以往采用的客户维系分析方法相比较，本方法显得更为合理。     

成数再保险和超额赔款再保险策略

针对比例再保险和非比例再保险,在分出公司最小盈余或利润目标确定和已知赔款额分布的情况下,把保持财务稳定性作为确定自留额的目标,根据VaR原理提出具有最优自留额的成数再保险与超额赔款再保险的策略.