Three different types of cation exchangers were produced from four basic poly(styrene-divinylbenzene) substrates with different properties. Porous PS-DVB resin beads were functionalized by sulfonation and sulfoacylation under various conditions to produce sulfonated resins with exchange capacities of 0.03-1.80 mM g(-1). The matrix with 50% of cross-linking is most suitable for updating by the proposed technique. Sulfuric and chlorosulfonic acids were used as the reagents for sulfonation. The sulfonating conditions, capacities, and the technique of the synthesis are given. The effects of parameters of the sulfonation reaction and the composition of the reactionary mixture on ion-exchange capacity of the sorbents were investigated. Selectivity and efficiency of the separation of some inorganic cations and derivatives of amines and hydrazines on the resins obtained are compared by ion chromatography with conductometric detection. As a result, the sulfoacylated resin was proved more efficient for the separation of these analytes. The resolution of the analytes strongly depends on the degree of functionalization. The best performance about 19,000 plates m(-1) was obtained using the sulfopropionylated beads with an ion-exchange capacity of 0.3 mM g(-1). The prepared sulfoacylated cation exchanger was compared with the commercially available Dionex CS-12 packing material. It was found that the separation of alkaline ions and 1,1-dimethylhydrazine (UDMH) were much better that those for the commercial material.
Introduction. The modern Russian education system is dominated by the attitude to consider non-adaptive aspects of the child’s behavior in the context of the problem. Meanwhile, it can be presented in a different way: in the aspect of insufficient development of certain social skills in a child. It is important to diagnose the presence of these shortcomings and resolve them at primary school age. Of particular relevance is the study of the social skills of children from dysfunctional families and families of the “risk group”. Theoretical analysis. In theoretical terms, the behavioral and psychological problems of younger students are considered in the context of insufficient development of their social skills. Mastering the latter, teaching correct behavior, we regard as a way to resolve the problems that a child has. Empirical analysis. The paper summarizes the results of an empirical study of the characteristics of social adaptation, the structure and level of formation of social skills of younger schoolchildren (N = 65), from families of the “risk group” (M = 8.65 years; N = 31) and children from socially well-off families (M = 9.81 years; N = 34). Social skills were studied using B. Furman’s methodology; features of the child’s socio-psychological adaptation – using the methodology of E. M. Aleksandrovskaya. Conclusion. Statistically significant differences were revealed in terms of indicators of social adaptation (goal-setting, moral and ethical readiness, behavior outside the classroom, relationships with classmates, attitude towards the teacher, emotional well-being) and indicators of the formation of a number of individual social skills of children from families of the “risk group” and children of the control group. The similarity of indicators of general group skills in two groups of younger schoolchildren was found. The applied aspect of the problem under study is related to the possibility of using the results in the development of psychological work programs with younger students.
Basic features of styrene polymerization under the action of 1,3-bis(l-lithio-l -methylhexyl)benzene (1) in the presence of tetrahydrofuran were studied. UV spectra of 1 and dilithiumpolystyrene in a benzene solution with an without THF were investigated. A comparison of the results of the UV spectra with the data of cryoscopy and viscometric measurements of "living" and deactivated polystyrene allows the conclusion that polystyrene chains propagating on the dilithium catalyst are in monomeric form.
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