Sec butyl and tert butyl cations were first stabilized upon cocondensation of aluminum chloride and haloalkanes (2 chlorobutane and 2 chloro 2 methylpropane, respectively) and their IR spectra and thermal stability investigated. Aluminum chloride anions participating in stabilization of carbenium ions were revealed. Ionic complexes and both 1:1 and 2:1 molecular complexes of reagents were detected and their IR spectra studied. Quantum chemical calcula tions at the PBE level of density functional theory with inclusion of electron correlation were employed to optimize the geometric parameters and to determine the vibrational frequencies of aluminum chloride, butyl chlorides, and their complexes of various compositions. The struc tures of the associates observed were determined on the basis of comparison of the experimental and calculated vibrational spectra.
The present article addresses the initial phase of the testing of the Vygotsky–Sakharov method for concept learning. This study involved 150 persons of the group of healthy subjects (no diagnosis registered) at the age of 18 to 45 years old (M=35.2, SD=8.65), 51 males and 99 females. The study used Vygotsky-Sakharov method. It tested two hypotheses: not all healthy participants would be able to solve the tasks of the Vygotsky-Sakharov method, healthy participants who coped with the tasks would not develop other preconceptual forms except the preconcept (which was one of the preconceptual forms), while in the group of those who did not not cope with the tasks, all the preconceptual forms should be registered. The present study showed that almost a quarter of the subjects of the control group could not solve the tasks (74% of the respondents solved them successfully, 26% failed). Along with the development of preconcepts, the generation of syncretic forms as well as complexes of the collection and diffuse types was characteristic of the both groups of the respondents who had solved the tasks successfully and unsuccessfully. 24% of the subjects gave responses of a syncretic type. As to the responses of a complex type, 18% of the respondents gave responses of a collection type, and 12% gave responses of a diffuse type. Answers and hypotheses with the complexes of nuclear and chain types were registered in no subject. Thus, group standards were identified according to the amount of time, correctional steps in solving the task and indices of the efficiency of conceptual thinking, and three gradations of the task performance were determined among the subjects who coped with it.
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