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91.
We consider operator algebras on an indefinite inner product space, which are induced by 1-derivations in C1-algebras, and give some conditions for boundedness of 1-derivations by using them. Also we show a close relationship between a 1-derivation and particular subspaces which are invariant under the algebra induced by that 1-derivation.  相似文献   
92.
Journal of Radioanalytical and Nuclear Chemistry - Tokatsu area was on one pathway of the radioactive plumes released in the Fukushima Daiichi Nuclear Power Plant accident and absorbed dose rate in...  相似文献   
93.
Non-equilibrium molecular dynamics (NEMD) are used to calculate the vortex or rotational viscosity of fluids composed of uniaxial molecules. It is shown that the NEMD homogeneous spin flow algorithm proposed by Edberg, R., Evans, D. J., and Moriss, G. P., 1987, Molec. Phys., 62, 1357 considerably underestimates the vortex viscosity. A modified version of this algorithm is proposed and applied to liquid chlorine and nitrogen. The results are in good agreement with previous work using equilibrium or other NEMD methods, and also show that at high spin rates the vortex viscosity decreases with increase in magnitude of the external torque used to drive the spin flow.  相似文献   
94.
We study the inventory management problem of a service center operating in a decentralized service parts network. The service centers collaborate through inventory and service pooling, and through sharing information on the inventory status. Upon demand arrival, a service center may request a part from the other center, in which case a payment is made. Under this competitive and collaborative environment, we first characterize the optimal operating policy of an individual service center. Through computational analysis we identify the conditions under which pooling is most beneficial to the service center, and make an assessment of different pooling strategies which are commonly adopted in practice and in the literature. Finally, we analyze the effect of interaction between the centers on the benefit of pooling.  相似文献   
95.
The effects of radiation on the formation of the agar-agar hydrogel were studied by measuring the penetration changes at different radiation doses and concentrations of added substances (sugar and potato starch). The behaviors of penetration against the radiation and the added substances were observed as follows. The experimental equations for the penetration changes were given by

A) P = a (log X)2 + b (log X)+c

B) P = b - a log t

C) P = b - a log S

where P is the relative penetration of the agar-agar hydrogel, X is the radiation dose, t is the elapsed time after irradiation, S is the concentration of the added substances, and a, b and c are adjustable constants.  相似文献   
96.
Abstract

The heat capacity of the nematogenic liquid crystal, HBAB, has been measured between 15 K and 385 K by using an adiabatic calorimeter. The crystal-crystal phase transition has been discovered at 27 K below the crystal-nematic phase transition temperature. The transition temperatures, the enthalpies and the entropies of the three phase transitions have been determined: T 1 = 306.98 K, ΔH t = 5.11 kJ mol?1, ΔS t = 16.7 JK?l; T m = 334.05 K, ΔH m = 23.77 kJ mol?1, ΔSm = 71.2 J K?l mol?1; and T c = 375.10 K, ΔH c = 1.75 kJ mol?1, ΔS c = 3.2 J K?1 mol?1, respectively. The thermodynamic functions of HBAB from 0 K to 385 K have been determined from the heat capacity data and the enthalpies of the transitions. Two crystal modifications, one yellow and granular form and the other white and needle-like form, have been obtained during the course of the preparation of the sample. It turned out that the yellow form was the stable crystal and the white the metastable modification. The crystal-crystal phase transition has been discussed as an onset of partial melting from the entropy consideration. In this connection the total entropies of the transitions, 91.1 J K?1 mol?1 has been proposed to be an important measure of melting.  相似文献   
97.
The effect of treating explicitly the coulombic and polarization interactions is investigated through the calculation of the coexistence curve of the pentane-H2S binary mixture. In this work, potential models have been developed for hydrogen sulphide and pentane, which include electrostatic sites—estimated from ab initio calculations—and polarizable sites—estimated from experimental data—in addition to Lennard-Jones sites. Compared to existing models, these new models have the same number of fitting parameters to experimental thermodynamic data. They are shown to correctly describe the coexistence curve of the pure compounds. When applied to the case of mixtures, together with Lorentz-Berthelot combining rules, they allow one to obtain a more accurate prediction of the coexisting compositions of the mixture. Furthermore, it is shown that the interaction energy in this kind of mixture cannot be properly described by using effective potential models usually considered for pure compounds.  相似文献   
98.
Photoelectron spectroscopy of isolated atoms and molecules using single-order high-harmonics of Ti:Sapphire laser pulses (800 nm, 12 fs/30 fs) is demonstrated. Dielectric multilayer mirrors, SiC/Mg and Mo/Si, are used to isolate the 27th (42 eV) and 59th (91 eV) order harmonics, respectively. The obtained harmonics are characterized by valence and inner-shell photoelectron spectroscopy of Xe. The applications to two-color two-photon ionization of He and pump-probe spectroscopy of ultrafast photodissociation of Br2, Br2(C1Πu)  Br(2P3/2) + Br(2P3/2), are presented.  相似文献   
99.
100.
Thiourea, thioglycol, and β, β′-thiodiglycolic acid were found to protect against changes in the internal relationships of the atoms in the protein molecule from radiation damage. The optical rotation behavior closely resembles that of amino acid which shows a similar dependence on concentration.  相似文献   
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