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1.
The 4-(trimethyl tin)butyl-2 radical, prepared and excited by the chemical activation reaction of H atoms with 4-(trimethyl tin)butene-1, was found to randomize its excess internal vibrational energy on a subpicosecond time scale. This result differs from an earlier study on the decomposition of 3-(triallyl tin)-2-fluoropropyl radical in which heavy-atom blocking of internal relaxation was reported.  相似文献   
2.
The main results of this paper are two distinct characterizations of interval orders and an upper bound on the dimension of an interval order as a function of its height. In particular, interval orders of height 1 have dimension of at most 2.  相似文献   
3.
Two systems, which are models of biological processes, are considered. These systems are notable for responding to different external actions nearly alike. This is associated with the fact that an external action excites only their natural intrinsic motions. Two kinds of external actions, harmonic and random, are studied. It is shown that each of them induces a transition to a new state that can be treated as a peculiar kind of phase transitions. Characteristics of these phase transitions are found.  相似文献   
4.
The influence of the electrical body forces and electrical tractions on the nonlinear response of ferroelectric stack actuators is analytically investigated. While the role of the electrical body forces and tractions in the response of piezoelectric actuators is well documented (and in many cases is not significant), the questions of their effect on ferroelectric active materials is still of interest. To examine this influence, the analytical model for the electro-mechanical behavior of a ferroelectric stack actuator is augmented to account for the electrical body forces along the actuator and the electrical tractions at the material–electrode interfaces. Focusing on the effect of the electrical forces and tractions on the ferroelectric domain switching phenomenon, the model is used for the numerical analysis of a ferroelectric layer and for the comparison with the case that neglects the electrical body forces and traction. The comparison theoretically designates cases in which the effect of the electrical body forces and tractions may be prominent and other cases where the classical approach that neglects these effects can be adopted.  相似文献   
5.
Application of the variable encounter method (VEM) has been made to the thermal cyclobutene decomposition system. Vibrational energy transfer in the cyclobutene-seasoned quartz surface system has been studied. The occurrence of strong collisions is demonstrated in crucial manner at temperatures below 400 K.  相似文献   
6.
Disproportionation–combination rate ratios have been measured for a number of pairs of thermalized radicals (298°K) generated by thermalization of chemically activated cycloalkyl radicals, their ring-opened products, and ethyl radicals. These ratios are reported and briefly discussed. The rate of isomerization of the chemically activated pent-2-en-5-yl radical via H-atom transfer to the allylic pent-1-en-3-yl radical is also given.  相似文献   
7.
The rank (resp. dimension) of a poset P is the cardinality of a largest (resp. smallest) set of linear orders such that its intersection is P and no proper subset has intersection P. Dimension has been studied extensively. Rank was introduced recently by Maurer and Rabinovitch in [4], where the rank of antichains was determined. In this paper we develop a general theory of rank. The main result, loosely stated, is that to each poset P there corresponds a class of graphs with easily described properties, and that the rank of P is the maximum number of edges in a graph in this class.  相似文献   
8.
The ground state energy of a hydrogen atom confined to a box, in the presence of an electric field is calculated. Boxes of various shapes are applied in order to demonstrate the shape's influence on that energy level. The procedure consists of numerically solving the two-dimensional Schrödinger equation using a finite element package.  相似文献   
9.
In order to confirm and extend the kinetic and intramolecular vibrational relaxation features observed in the isopropylcyclobutane system (KR), the sub  相似文献   
10.
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