The interaction of cetyl trimethylammonium bromide (CTAB)and an anionic copolymer derived from 3\|sulfopropylmethacrylate, potassium salt (SPMS) and styrene (St) in aqueous solutions has been studied. It was found tha...The interaction of cetyl trimethylammonium bromide (CTAB)and an anionic copolymer derived from 3\|sulfopropylmethacrylate, potassium salt (SPMS) and styrene (St) in aqueous solutions has been studied. It was found that the viscosity of the anionic copolymer\|CTAB solution rises suddenly in a specific molar ratio of CTAB/anion. For instance, the viscosity of polymer (No.1) solutions increases to about 20 times at CTAB/\|SO\-3K=1.0～1 05, and increases to about 100 times at CTAB/\|SO 3K=1.4～1 5. In the case of polymer samples No.2 and No.3, the changes of solution viscosity are similar to that of sample No.1, but the gelation takes place at CTAB/\|SO\-3K=1.4～1 5 region because of the lower negative charge density on No.2 and No.3 polymer chains. It is proposed that the dramatical change of the P(SPMS-co-St)/CTAB aqueous solution is ascribed to the aggregation behavior of CTAB, then the P(SPMS-co-St) aggregates. This consideration was verified by fluorescence determination and laser light scattering experiments. Using DMAF as fluoresscent probe, the hydrophobic microdomain existed in P(SPMS-co-St)/CTAB aqueous solutions in the viscosity rising region has been confirmed and it is in agreement well with the results obtained by laser light scattering determination.展开更多
一、系统设计1 .系统设计的背景《智力量表》依据心理学理论而制定,能够对人的智力进行多方面、多结构的分析,风行于美国、西欧等发达国家,有较高的社会效益.其中《瑞文标准推理测验》(Raven’s Standard Progressive Matrices简称SPM)...一、系统设计1 .系统设计的背景《智力量表》依据心理学理论而制定,能够对人的智力进行多方面、多结构的分析,风行于美国、西欧等发达国家,有较高的社会效益.其中《瑞文标准推理测验》(Raven’s Standard Progressive Matrices简称SPM)是英国心理学家瑞文(J.C.Raven)1938年设计的非文字智力测验.自其问世以来,许多国家对它做了修订,直至现在仍在广泛使用,有着重要的理论意义与实用价值.在我国的心理学家的不断努力下,我国已经引进了《智力量表》的许多经典之作.并针对中国自已的情况做了修订.但是,在现实生活中,《智力量表》并未起到其应起的作用.这其中不可忽视的一个原因是:《智力量表》展开更多
Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are software...Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are softwares for analyzing fishery catch and fishing effort data using nonequilibrium SPMs.In China Fishery Statistical Yearbook,annual fishery production and fishing effort data of the Yellow Sea,Bohai Sea,East China Sea,and South China Sea have been published from 1979 till present.Using its catch and fishing effort data from 1980 to 2018,we apply the CEDA and ASPIC to evaluate fishery resources in Chinese coastal waters.The results show that the total maximum sustainable yield(MSY)estimate of the four China seas is 10.05-10.83 million tons,approximately equal to the marine fishery catch(10.44 million tons)reported in 2018.It can be concluded that China’s coastal fishery resources are currently fully exploited and must be protected with a precautionary approach.Both softwares produced similar results;however,the CEDA had a much higher R2 value(above 0.9)than ASPIC(about 0.2),indicating that CEDA can better fit the data and therefore is more suitable for analyzing the fishery resources in the coastal waters of China.展开更多
文摘The interaction of cetyl trimethylammonium bromide (CTAB)and an anionic copolymer derived from 3\|sulfopropylmethacrylate, potassium salt (SPMS) and styrene (St) in aqueous solutions has been studied. It was found that the viscosity of the anionic copolymer\|CTAB solution rises suddenly in a specific molar ratio of CTAB/anion. For instance, the viscosity of polymer (No.1) solutions increases to about 20 times at CTAB/\|SO\-3K=1.0～1 05, and increases to about 100 times at CTAB/\|SO 3K=1.4～1 5. In the case of polymer samples No.2 and No.3, the changes of solution viscosity are similar to that of sample No.1, but the gelation takes place at CTAB/\|SO\-3K=1.4～1 5 region because of the lower negative charge density on No.2 and No.3 polymer chains. It is proposed that the dramatical change of the P(SPMS-co-St)/CTAB aqueous solution is ascribed to the aggregation behavior of CTAB, then the P(SPMS-co-St) aggregates. This consideration was verified by fluorescence determination and laser light scattering experiments. Using DMAF as fluoresscent probe, the hydrophobic microdomain existed in P(SPMS-co-St)/CTAB aqueous solutions in the viscosity rising region has been confirmed and it is in agreement well with the results obtained by laser light scattering determination.
文摘一、系统设计1 .系统设计的背景《智力量表》依据心理学理论而制定,能够对人的智力进行多方面、多结构的分析,风行于美国、西欧等发达国家,有较高的社会效益.其中《瑞文标准推理测验》(Raven’s Standard Progressive Matrices简称SPM)是英国心理学家瑞文(J.C.Raven)1938年设计的非文字智力测验.自其问世以来,许多国家对它做了修订,直至现在仍在广泛使用,有着重要的理论意义与实用价值.在我国的心理学家的不断努力下,我国已经引进了《智力量表》的许多经典之作.并针对中国自已的情况做了修订.但是,在现实生活中,《智力量表》并未起到其应起的作用.这其中不可忽视的一个原因是:《智力量表》
基金This study is supported by the project from the Food and Agriculture Organization of the United Nations(FAO)(No.GF.FIRFD.RA20403020400).
文摘Surplus production models(SPMs)are among the simplest and most widely used fishery stock assessment models.The catch-effort data analysis(CEDA)and a surplus production model incorporating covariates(ASPIC)are softwares for analyzing fishery catch and fishing effort data using nonequilibrium SPMs.In China Fishery Statistical Yearbook,annual fishery production and fishing effort data of the Yellow Sea,Bohai Sea,East China Sea,and South China Sea have been published from 1979 till present.Using its catch and fishing effort data from 1980 to 2018,we apply the CEDA and ASPIC to evaluate fishery resources in Chinese coastal waters.The results show that the total maximum sustainable yield(MSY)estimate of the four China seas is 10.05-10.83 million tons,approximately equal to the marine fishery catch(10.44 million tons)reported in 2018.It can be concluded that China’s coastal fishery resources are currently fully exploited and must be protected with a precautionary approach.Both softwares produced similar results;however,the CEDA had a much higher R2 value(above 0.9)than ASPIC(about 0.2),indicating that CEDA can better fit the data and therefore is more suitable for analyzing the fishery resources in the coastal waters of China.
