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61.
利用重离子熔合蒸发反应149Sm(27Al,4nγ)172Re布居了形变双奇核172Re的高自旋态,用12套带有BGO反康普顿抑制的高纯锗探测器阵列进行了在束γ实验测量,首次建立了形变双奇核172Re由3个转动带构成的高自旋态能级纲图.研究和讨论了3个转动带的结构特征,基于已有的高自旋态核结构知识并通过系统学比较和分析指出它们的准粒子组态分别为πh11/2⊙νi13/2,πh9/2⊙νi13/2和π1/2-[541]⊙ν1/2-[521].发现前两个转动带在自旋小于18.5h时其转动能级呈现反常的旋称劈裂. 相似文献
62.
We consider the problem of finding solutions of systems of monotone equations. The Newton-type algorithm proposed in Ref. 1 has a very nice global convergence property in that the whole sequence of iterates generated by this algorithm converges to a solution, if it exists. Superlinear convergence of this algorithm is obtained under a standard nonsingularity assumption. The nonsingularity condition implies that the problem has a unique solution; thus, for a problem with more than one solution, such a nonsingularity condition cannot hold. In this paper, we show that the superlinear convergence of this algorithm still holds under a local error-bound assumption that is weaker than the standard nonsingularity condition. The local error-bound condition may hold even for problems with nonunique solutions. As an application, we obtain a Newton algorithm with very nice global and superlinear convergence for the minimum norm solution of linear programs.This research was supported by the Singapore-MIT Alliance and the Australian Research Council. 相似文献
63.
This paper presents an optical method which is based on speckle-shearing interferometry for the measurement of the slope at any point of an object. The object under study is illuminated by an expanded laser beam and its image is recorded on a photographic plate placed at the image plane of an image-shearing camera. A second exposure on the photographic film is made after the light source is moved slightly. The resulting photograph yields a fringe pattern which represents lines of constant displacement gradients. Theory of the method as well as some experimental results are presented. 相似文献
64.
宋立涛 周小红 郭应祥 孙志宇 M.Oshima T.Toh A.Osa M.Koizumi J.Katakura Y.Hatsukawa M.Matsuda M.Sugawara 《中国物理 C》2004,28(2):148-151
利用能量为164—180MeV的35Cl束流,通过重离子核反应149Sm(35Cl,5n)研究了179Au的高自旋态能级结构.实验进行了γ射线的激发函数、X-γ和γ-γ-t符合测量.基于对实验测量结果的分析,首次建立了179Au的1/2[660](πi13/2)转动带.结合已有的实验数据,着重讨论了奇AAu核中1/2[660](πi13/2)转动带的带头激发能随中子数的变化 相似文献
65.
The pressure and laser-power dependence of the product distributions in the TEA CO2 laser induced decomposition of trichloroethylene were studied. At moderate pressures molecular elimination of HCl to give CClCCl via intermolecular energy transfer was found to be the major reaction path. At low pressures a pure laser-induced CCl bond fission to give CHCCl was found to be the primary, reaction step. 相似文献
66.
Viscosities of solutions of polystyrene in toluene were measured for concentrations up to 400 kg m?3 at 298 K. Polymers of molecular weights ranging from 8.7 × 103 to 2.4 × 106 were used. It is observed that viscosity of the polymer solution increases with increasing concentration and molecular weight; the rate of increase is greater at higher values of the two parameters. A master curve for the system is constructed by using the experimental data for viscosity, concentration and molecular weight of the polymer. Regions of various polymer interactions in solution are identified. 相似文献
67.
Pyrolysis of 3,5-dimethyl-1-propynoylpyrazole (1) at 640°C/0.1 torr gives 2-methyl-1-pyrazolo[2,3-a]pyridin-5-one (3) with inversion of the propynoyl chain. 1-Ethynylpyrazole and tricarbon monoxide have been identified in pyrolysates formed at 700–1000°C/0.01–0.1 torr from the parent 1-propynoylpyrazole (4). 相似文献
68.
Hian Poh Yap 《Journal of Graph Theory》1981,5(2):159-163
We prove that if K is an undirected, simple, connected graph of even order which is of class one, regular of degree p ≥ 2 and such that the subgraph induced by any three vertices is either connected or null, then any graph G obtained from K by splitting any vertex is p-critical. We find that various constructions of critical graphs by S. Fiorini are special cases of a corollary of this result. 相似文献
69.
Recent experiments on ferroelectric gating have introduced a novel functionality, i.e., nonvolatility, in graphene field-effect transistors. A comprehensive understanding in the nonlinear, hysteretic ferroelectric gating and an effective way to control it are still absent. In this Letter, we quantitatively characterize the hysteretic ferroelectric gating using the reference of an independent background doping (n(BG)) provided by normal dielectric gating. More importantly, we prove that n(BG) can be used to control the ferroelectric gating by unidirectionally shifting the hysteretic ferroelectric doping in graphene. Utilizing this electrostatic effect, we demonstrate symmetrical bit writing in graphene-ferroelectric field-effect transistors with resistance change over 500% and reproducible no-volatile switching over 10? cycles. 相似文献
70.
Various conic relaxations of quadratic optimization problems in nonnegative variables for combinatorial optimization problems, such as the binary integer quadratic problem, quadratic assignment problem (QAP), and maximum stable set problem have been proposed over the years. The binary and complementarity conditions of the combinatorial optimization problems can be expressed in several ways, each of which results in different conic relaxations. For the completely positive, doubly nonnegative and semidefinite relaxations of the combinatorial optimization problems, we discuss the equivalences and differences among the relaxations by investigating the feasible regions obtained from different representations of the combinatorial condition which we propose as a generalization of the binary and complementarity condition. We also study theoretically the issue of the primal and dual nondegeneracy, the existence of an interior solution and the size of the relaxations, as a result of different representations of the combinatorial condition. These characteristics of the conic relaxations affect the numerical efficiency and stability of the solver used to solve them. We illustrate the theoretical results with numerical experiments on QAP instances solved by SDPT3, SDPNAL+ and the bisection and projection method. 相似文献