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101.
102.
本文从“同温度层不完全平行于地面,且在变化”的“任意分层”假设出发,导出了水准折光修正公式,并利用光的色散效应在10~(-6)的精度要求下,求得r=r_T=h_1/h_2=(n_(01)-1)/(n_(02)-1)=常数最后指出,研制双波长激光水准仪的必要性和可能性,并提出了研制此种仪器的技术参数. 相似文献
103.
Yuichiro Tada Masakatsu Ueno Noriaki Tsuchihashi Kiyoshi Shimizu 《Journal of solution chemistry》1992,21(9):971-985
The limiting molar conductances ° of deuterium chloride DCl in D2O were determined as a function of pressure and temperature in order to examine the proton-jump mechanism in detail. The excess deuteron conductances °E(D
+), as estimated by the equation [°E(D
+) = °(DCl/D
2
O) – °(KCl/D
2
O)], increases with an increase in the pressure and temperature as well as the excess proton conductance [°E(H
+) = °(HCl/H
2
O) – °(KCl/H
2
O)]. The isotope effect on the excess conductances, however, depends on the pressure and temperature contrary to the model proposed by Conway et al.: °E(H
+)/°E(D
+) decreases with increasing pressure and temperature. The magnitude of the decrease with pressure becomes more prominent at lower temperature. These results are discussed in terms of the pre-rotation of adjacent water molecules, the bending of hydrogen bonds with pressure, and the difference in strength of hydrogen bonds between D2O and H2O. 相似文献
104.
Thomas Unnerstall 《Journal of statistical physics》1989,54(1-2):379-403
The irreversible macroscopic dynamics of the Josephson junction coupled to external wires acting as a current source is derived rigorously from the underlying microscopic Hamiltonian quantum mechanics. The external systems are treated in the singular coupling limit. The use of this limit is explicitly justified via an interpretation of the singular coupling limit in terms of the relative magnitudes of system, reservoir, and coupling energies. The qualitative behavior of the macroscopic dynamical equations is shown to depend sensitively and crucially on the interaction between the wires and the superconductors and on the size of the wires: the dc Josephson effect only happens when one lets Cooper pairs be driven into the junction by collective (i.e., small) reservoirs. 相似文献
105.
106.
107.
选择不同电离电位的基体元素K、Na、La、Y和Mg,比较研究了它们对分析元素谱线强度的影响,其影响程度与谱线激发电位及基体元素电离电位有定量的相关关系。碱金属基体(K、Na)和非碱金属基体(La、Y和Mg)对分析元素检出限、背景强度及其相对标准偏差的影响显著不同,后者的记忆效应也大于前者。La的电离电位与Na相差不大。但其基体效应与Y相似,表明墓体效应与基体元素的化学性质有关。 相似文献
108.
A series of benzylideneanilines bearing terminal polyether chains, HL (HL = R-C6H4-CHN-C6H4-R′: R = OC8H17, R′ = O(CH2CH2O)2C2H5; R = O(CH2CH2O)2C2H5, R′ = OC8H17; R = R′ = O(CH2CH2O)2C2H5; R = OC12H25, R′ = O(CH2CH2O)3C2H5; R = O(CH2CH2O)3C2H5, R′ = OC12H25; R = R′ = O(CH2CH2O)3C2H5) have been prepared. Their dinuclear, [Pd(μ-X)L]2 (X = OAc, Cl, Br, SC8), [Pd2(μ-SCn)(μ-X)L2] (X = OAc, Cl; n = 8, 2) and mononuclear orthopalladated derivatives, Pd(acac)L, Pd(Ala)L, are reported and their mesogenic properties are compared with those of the analogous compounds with alkoxy chains. In general a great lowering in the melting points is produced for all the products. The free ligands and the alanine complexes are not liquid crystals. The chloro-bridged complexes bearing alkoxy and short polyether chains (O(CH2CH2O)2C2H5) show the larger improvement of mesogenic properties. Longer polyether chains (O(CH2CH2O)3C2H5) result usually in a destabilization of the mesophases. If only polyether chains are present, the destabilization is important regardless of the chain length. The ability of these molecules as ionic extractants and transporters was qualitatively evaluated for the more propitious cis-dinuclear complexes, which in fact showed some extracting ability, modest but improved compared to the free ligands. 相似文献
109.
Enthalpies of solution have been measured from 5 to 85°C for aqueous tetraethyl- and tetrapropylammonium bromides, and the integral heat method is employed to evaluate
for these electrolytes over a wide temperature range. Data taken from the literature have been used to evaluate
for aqueous Bu4NBr over a similar temperature range. These data, along with similar data for Me4NBr, previously reported, have been used to evaluate absolute ionic heat capacities. While the absolute values agree only qualitatively with two other methods of division, the temperature dependences of the three methods essentially agree up to 65°C. Heat capacities due to structural effects on the solvent, obtained by subtracting the inherent heat capacities of the ions, are extraordinarily positive for all four tetraalkylammonium ions and have negative temperature coefficients, indicating that all four ions, including the tetramethylammonium ion, are structure-making ions. 相似文献
110.
The effect of CuO on the thermal behaviour of Zr/KClO4 primer mixtures was studied by thermoanalytical techniques, and the Bruceton method and its related calculation. It was found that the CuO catalytically promoted the decomposition of Zr/KClO4 primer mixtures and shifted the exothermic peak of DSC curves to lower temperatures. In addition, the Zr/KClO4 primer mixture containing CuO had a significant effect on the firing characteristics of electro-explosive devices. 相似文献