Synthesis and some reactions of indolo[2,1-c]-1,4-oxazinium perchlorates

Summary The reaction of acyl perchlorates with 1 phenacylskatole affords the previously unknown 1-R-lamethyl-3phenylindolo[2,1-c1-1,4oxazinium salts, which undergo recyclization by the action of ammonia to the corresponding indolo[2,1-alpyrazines. It is found that the salts (R = CHj, CZHS) also form dimers of their anhydro bases. The perchlorate (R = Ph) is converted to indolo[2,141-1, 2, S-triazepine by the action of hydrazine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1041-1047, August, 1994.     

Si1－xGex/Si量子阱发光材料的分子束外延生长及其结构研究

采用固源Si分子束外延,在较高的生长温度于Si(100)衬底上制备出Si1－xGex/Si量子阱发光材料。发光样品的质量和特性通过卢瑟福背散射、X射线双晶衍射及光致发光评估。背散射实验中观察到应变超晶格的反常沟道效应;X射线分析表明材料的生长是共度的、无应力释放的,结晶完整性好。低温光致发光主要是外延合金量子阱中带边激子的无声发射和横光学声子参与的激子复合。并讨论了生长温度对量于阱发光的影响。     

Transport properties of polyphenylquinoxalines

The correlation between chemical structure and gas transport properties is considered for a new class of membrane materials based on structurally similar polyphenylquinoxalines that are characterized by different numbers of flexible-O-ether bonds in the repeating unit and different chain rigidities. Permeability, diffusion, and solubility coefficients have been estimated for the gases H₂, He, O₂, N₂, CO, CO₂, and CH₄; separation factors for various gas pairs have been determined. For the materials with a similar level of cohesive energy density, which characterizes interchain interactions, permeability decreases with a decrease in chain rigidity, whereas selectivity of gas separation increases.     

Weak convergence of quadratically Gaussian measures

Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 41, No. 5, pp. 626–631, May, 1989.     

Infinite-dimensional linear groups with restrictions on subgroups that are not soluble <Emphasis Type="Italic">A</Emphasis><Subscript>3</Subscript>-groups

We are concerned with infinite-dimensional locally soluble linear groups of infinite central dimension that are not soluble A₃-groups and all of whose proper subgroups, which are not soluble A₃-groups, have finite central dimension. The structure of groups in this class is described. The case of infinite-dimensional locally nilpotent linear groups satisfying the specified conditions is treated separately. A similar problem is solved for infinite-dimensional locally soluble linear groups of infinite fundamental dimension that are not soluble A₃-groups and all of whose proper subgroups, which are not soluble A₃-groups, have finite fundamental dimension. __________ Translated from Algebra i Logika, Vol. 46, No. 5, pp. 548–559, September–October, 2007.     

Mathematical modelling and analytical solution for workpiece temperature in grinding

This paper deals with modelling the workpiece temperature field produced during the grinding process. The proposed model is given in terms of a two-dimensional boundary-value problem where the interdependence among the grinding wheel, the workpiece and the coolant is described by two variable functions in the boundary condition. An explicit integral form solution is constructed using the Laplace and Fourier transforms and the Green’s function method.     

<Superscript>6</Superscript>He + <Superscript>6</Superscript>He Clustering of <Superscript>12</Superscript>Be in a Microscopic Algebraic Approach

The norm kernel of the A=12 system composed of two ⁶He clusters, and the L=0 basis functions (in the SU(3) and angular momentum-coupled schemes) are analytically obtained in the Fock-Bargmann space. The norm kernel has a diagonal form in the former basis, but the asymptotic conditions are naturally defined in the latter one. The system is a good illustration for the method of projection of the norm kernel to the basis functions in the presence of SU(3) degeneracy that was proposed by the authors. The coupled-channel problem is considered in the algebraic version of the resonating-group method, with the multiple decay thresholds being properly accounted for. The structure of the ground state of ¹²Be obtained in the approximation of zero-range nuclear force is compared with the shell-model predictions. In the continuum part of the spectrum, the S-matrix is constructed, the asymptotic normalization coefficients are deduced and their energy dependence is analyzed.