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121.
The embedding theorem ofZ-graded Lie superalgebras is given and proved. As a subsidiary result it is proved that a transitiveZ-graded restricted lie superalgebm must be isomorphic toW(m,n, 1) if the dimension ofG i satisfies a certain condition. Project supported by the National Natural Science Foundation of China and the Science of the University Doctoral Program of CNEC.  相似文献   
122.
We consider the blow-up problem for the nonlinear Schrödinger equation with quartic self-interacting potential on . We exhibit a class of initial data leading to the blow-up solutions which have at least two L 2-concentration points.  相似文献   
123.
Given a finitely generated restricted Lie algebra L over the finite field \(\mathbb{F}_q \), and n ≥ 0, denote by a n (L) the number of restricted subalgebras H ? L with \(\dim _{\mathbb{F} _q} \) L/H = n. Denote by ã n (L) the number of the subalgebras satisfying the maximality condition as well. Considering the free restricted Lie algebra L = F d of rank d ≥ 2, we find the asymptotics of ã n (F d ) and show that it coincides with the asymptotics of a n (F d ) which was found previously by the first author. Our approach is based on studying the actions of restricted algebras by derivations on the truncated polynomial rings. We establish that the maximal subalgebras correspond to the so-called primitive actions. This means that “almost all” restricted subalgebras H ? F d of finite codimension are maximal, which is analogous to the corresponding results for free groups and free associative algebras.  相似文献   
124.
介绍了化工原理课程思政的育人目标,据此构建课程内容与育人元素的支撑矩阵;融入绿色工程理念,确定课程对绿色工程十二项原则指标点的支撑;深度融合信息技术,基于原有慕课建设专门的课程思政慕课;以精馏章节为例,分享化工原理课程思政教学案例设计思路和方案。同时,对学生测评和学习成果、育人点、重要性及切入自然性进行调研评价,说明通过课程思政教学实践,在潜移默化中培养学生树立正确的世界观、人生观和价值观。为化工类专业课程思政教学提供参考和借鉴。  相似文献   
125.
In this paper, we present a general solution of the scalar Riemann problem on a closed Riemann surface in the case of a compound contour in the class of piecewise meromorphic functions multiple of a given divisor. All the results are known and belong to the author [15–17], except for the existence theorems and properties of basic functionals and also properties of a θ-function. The solution of the problem in a ‘special case’ has been announced by the author but not published [15]. Similar problems and some applications are considered in [1, 2, 12]. The main results of the paper were obtained by the author during his collaboration with Professor G. S. Litvinchuk, and this paper is devoted to his cherished memory. Received: April 13, 2007. Accepted: June 13, 2008.  相似文献   
126.
Among numerous iterative methods for solving the minimal nonnegative solution of an M‐matrix algebraic Riccati equation, the structure‐preserving doubling algorithm (SDA) stands out owing to its overall efficiency as well as accuracy. SDA is globally convergent and its convergence is quadratic, except for the critical case for which it converges linearly with the linear rate 1/2. In this paper, we first undertake a delineatory convergence analysis that reveals that the approximations by SDA can be decomposed into two components: the stable component that converges quadratically and the rank‐one component that converges linearly with the linear rate 1/2. Our analysis also shows that as soon as the stable component is fully converged, the rank‐one component can be accurately recovered. We then propose an efficient hybrid method, called the two‐phase SDA, for which the SDA iteration is stopped as soon as it is determined that the stable component is fully converged. Therefore, this two‐phase SDA saves those SDA iterative steps that previously have to have for the rank‐one component to be computed accurately, and thus essentially, it can be regarded as a quadratically convergent method. Numerical results confirm our analysis and demonstrate the efficiency of the new two‐phase SDA. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
127.
Simplified Box Orbitals (SBO) are a kind of spatially restricted basis functions. SBOs have a similar use and value to Slater functions but, because they fulfill a version of the zero‐differential overlap approximation, they allow for a drastic reduction in the number of two‐electron integrals to be calculated when dealing with huge systems, and they seem to be specially adapted to study confined systems such as molecules in solution. In a previous study, the mathematical shape of SBOs was discussed and the necessary parameters were obtained by means of the variational method. In the present study, the parameters of each SBO were obtained by applying the condition that it is as similar as possible to the STO that would be used in a basis set without spatial restrictions. We have developed a method to achieve this likeness and deduced simple formulas to describe all the SBOs of any atom. We also present the SBO‐3G expansions of the SBOs obtained, making it possible to use these SBOs with standard quantum chemistry calculation software. Simple formulas were also deduced to directly write the SBOs and SBO‐3G corresponding to the atoms with a Z value of between 1 and 18. Finally, as a first example of the usefulness of this kind of functions, an optimized SBO‐3G basis set is proposed for atoms from H to Cl in molecules. © 2016 Wiley Periodicals, Inc.  相似文献   
128.
In this article, the topic of "chemical principles in warmer pad" is used as an example to illustrate how problem-based learning (PBL) and case learning (CL) are used in the teaching of general chemistry. We take the advantages of PBL to arouse the studying interests of students in the casing learning atmosphere. Moreover, the teacher leads the discussion. By using these two teaching methods properly, students' active learning ability, the skills of analyzing and solving problems, as well as the comprehensive practical ability can be improved.  相似文献   
129.
130.
Sufficient conditions for the existence of at least one T-periodic solution of nonlinear functional difference equation
Δx(n)+a(n)x(n)=f(n,u(n)),  相似文献   
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