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71.
In this paper a complete proof for the existence of generalized operators satisfying abstract 02 dynamical equations of quantum motions δ^2/δt^2Ф(t, x) + ( △- m^2)Ф(t, x) = -λ :Ф^3(t, x), subject to a suitable initial condition, is given under the framework of white noise analysis. Also some important commutation relations related to Ф44 quantum fields are discussed and proved in detail.  相似文献   
72.
Let B be the class of 'better' admissible multimaps due to the author. We introduce new concepts of admissibility (in the sense of Klee) and of Klee approximability for subsets of G-convex uniform spaces and show that any compact closed multimap in B from a G-convex space into itself with the Klee approximable range has a fixed point. This new theorem contains a large number of known results on topological vector spaces or on various subclasses of the class of admissible G-convex spaces. Such subclasses are those of O-spaces, sets of the Zima-Hadzic type, locally G-convex spaces, and LG-spaces. Mutual relations among those subclasses and some related results are added.  相似文献   
73.
用高温固相法合成了系列化合物RE0.06La0.94M2O6Br(M=Nb,Ta;RE=Eu,Tb,Pr,Sm),并测定了其激发和发射光谱,室温下Eu3+、Tb3+、Pr3+、Sm3+在稀土-铌(钽)复合溴氧化物中呈现特征激发谱线,但Nb和Ta的光谱特性稍有不同。  相似文献   
74.
La3Ga5.5Ta0.5O14 (LGT) crystal was grown by using the Czochralski method. The as‐grown crystal is transparent, free from inclusions and with no cracks. Specific heat, thermal expansion, dielectric constants, transmission spectrum and optical damage threshold of LGT have been measured, and the results show general properties of LGT are similar to that of La3Ga5SiO14 (LGS) crystal. The experiment to research the Q‐switch properties of LGT has been performed and the results show LGT possesses smaller electrooptic coefficients than that of LGS and may not be an ideal material used as a Q‐switch. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
75.
Tetrazole (H2CN4) and tetrazolate anion (HCN$_{4}^{-}$) are high‐energy compounds with a five‐membered ring‐type structures, which can be easily synthesized by HCN and HN3 and by HCN and N$_{3}^{-}$, respectively, in an irreversible reaction. The ab initio methods including MP2/6‐31G**, B3LYP/6‐31G**, B3LYP/6‐311+G(2d,p), and CBS/QB3 from Gaussian 98 program are employed to study the thermochemistry and reaction mechanism. The transition states of both HCN + HN3 → H2CN4 and HCN + N$_{3}^{-}$ → HCN$_{4}^{-}$ reaction are investigated, and it is found that the latter reaction is more favored than the former one in view of the chemical kinetics and thermodynamics, thus indicating that tetrazole (H2CN4) and tetrazolate anion (HCN$_{4}^{-}$) are formed more easily in an alkali environment than in other systems. Pentazole (HN5) is an unknown high‐energy compound and has not yet been synthesized. For comparison, HN5 and N$_{5}^{-}$, both which have similar type of synthetic reactions to the above‐mentioned reactions, are studied. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 80: 27–37, 2000  相似文献   
76.
77.
Na0.74Ta3O6, a Low‐Valent Oxotantalate with Multiple Ta–Ta Bonds The title compound was prepared in a sealed tantalum tube through the reaction of Ta2O5, tantalum and Na2CO3 in a NaCl flux at 1570 K within 5 d. The crystal structure of Na0.74Ta3O6 (a = 713.5(1), b = 1027.4(2), c = 639.9(1) pm, Immm, Z = 4) was determined by single crystal X‐ray means. The structure is isomorphous with NaNb3O5F [1]. The characteristic structural units are triply bonded Ta12 dumb‐bells with eight square‐prismatically co‐ordinated O ligands. Four Ta2, each octahedrally surrounded by O atoms, are side‐on bonded weakly to the binuclear Ta2O8 complex, thus forming a Ta6 propellane‐like cluster. The lattice parameters of three additional MxTa3O6 phases, M = Li, Mn, and Yb, are reported.  相似文献   
78.
We have fabricated Pt/SBT/insulator/Si structure for the transistor gate in MFIS-FET and investigated the electrical properties of MFIS structure with various insulator materials. SrBi2Ta2O9 films as a ferroelectric layer were deposited by metal organic decomposition (MOD) technique, on various insulator structures including SiON, and Al2O3 as well as on Pt/Ti/SiO2/Si structures. The effect of annealing temperature on the electrical properties of MFIS structures was investigated in order to analyze the applicability to conventional CMOS process. Although the remnant polarization of SBT films for MFM structure was increased with increasing annealing temperature, the memory window which has a relationship with remnant polarization of ferroelectrics was differently displayed with insulator structure in MFIS structure.  相似文献   
79.
Optical near-field interactions exhibit hierarchical responses in the nanometer scale allowing unique functions in nanophotonic systems. Such hierarchical properties in optical near-fields originate various physical entities in the nanometer scale. Engineering nanomaterial compositions, while maintaining geometrically equivalent conditions, leads to characteristic hierarchical responses. We experimentally demonstrate such material-dependent optical near-field hierarchy using core–shell-type nanostructures composed of gold and silver.  相似文献   
80.
An optical backplane based on a meshed polymer waveguide architecture enabling high-speed board-to-board optical interconnection is presented. This planar array of multimode polymer waveguides can provide passive strictly non-blocking links between server line cards fitted with optical transmitter and receiver arrays. This architecture offers a scalable and low-cost solution to the bandwidth limitations faced by electrical backplanes and is suitable for PCB integration. The reported backplane demonstrator uses a matrix of 100 waveguides each capable of 10 Gb/s operation to interconnect 10 cards for a total capacity of a terabit per second aggregate data rate in multicast mode. Characterisation of the backplane demonstrator reveals low link losses of 2 to 8 dB for a multimode fibre input and crosstalk values below −35 dB. Error free data transmission at 10 Gb/s is achieved with a power penalty of only 0.2 dB at a bit-error-rate of 10−9. Additionally, lossless operation of a Gigabit Ethernet link over the backplane is achieved even when using the worst-case highest loss links.  相似文献   
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