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A. A. Levchenko G. V. Kolmakov L. P. Mezhov-Deglin V. B. Shikin E. Teske P. Leiderer 《JETP Letters》1997,65(7):572-578
A change in the shape of a charged surface of liquid hydrogen and helium — the formation of a solitary wave (a positively
charged hump for hydrogen and a negatively charged dimple for helium)-is observed in an electric field exceeding a critical
value under conditions of total compensation of the applied field by the surface charge.
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 7, 547–552 (10 April 1997) 相似文献
3.
硅基材料是新一代高容量锂离子蓄电池负极材料的典型代表,近年来已成为理论研究和应用研究的热点.本文介绍了锂离子电池硅基负极材料的制备方法、电化学性能及其研究现状,分析了硅材料作为锂离子电池负极材料存在的问题;讨论了硅材料作为锂离子电池负极材料的研究前景.并指出若能克服目前存在问题,将有望成为新一代锂离子电池负极材料. 相似文献
4.
Preparation, Properties and Crystal Structure of Bis(phthalocyaninato)cerium(IV) The anodic or chemical oxidation with dibenzoylperoxide of solutions of bis(phthalocyaninato)cerate(III) in dichloromethane yields selectively sparely soluble bis(phthalocyaninato)cerium(IV), [Ce(Pc(2-)) 2 ]. Green, monoclinic needles cristallize with a = 18.783(12) Å b = 18.739(16) Å c= 15.618(10) Å ß114.30(7)°; Z = 4; space group C2/c. [Ce(Pc(2–)) 2 ] is a sandwich complex in which the cerium Atom is eightfold coordinated by the isoindole nitrogens of the two staggered convex Pc-rings. The u.v.-vis., m.i.r., f.i.r. and resonance Raman spectra are consistent with the structure. 相似文献
5.
A convenient method has been developed for the separation of alkaline phosphates (AP) isoenzymes from canine plasma. The various forms of AP activity were extracted by ethanol and separated on an anion exchanger by fast protein liquid chromatography. In this way a complete discrimination was achieved between the increase in plasma AP activity due to liver disease and that due to corticosteroid induction. The corticosteroid-induced form of AP could be separated from the other isoenzymes because of its relative heat stability at 65 degrees C. A quantitation of the contribution of liver and corticosteroid-induced AP isoenzymes to the total plasma AP activity could be made from the respective heat inactivation plots. The separation of the isoenzymes may be valuable in the purification of the different isoenzymes for further characterization. 相似文献
6.
Synthesis and Structure of the First Ternary Lead(II) Copper(I) Oxide: PbCu2O2 PbCu2O2 can be prepared by solid state reaction or by precipitation from a basic aqueous solution. Single crystals of the new compound were prepared by recrystallisation from a molten mixture (PbO? Cu2O) and investigated by X-ray diffractometer technique. PbCu2O2 crystallizes isotypically with the homologue silver compound PbAg2O2 (monoclinic with a = 8.223 Å, b = 8.289 Å, c = 6.015 Å, β = 132.62°, Z = 4, space group C? C 1 2/c 1). The crystallographic data from the X-ray investigation are reported. The structure is built by endless [PbO4/4]- and [CuO2/4]-chains. Pb2+ has a one-sided asymmetric coordination with four next oxygen neighbours and Cu+ forms a stretched dumbbell with two oxygen atoms. 相似文献
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Summary The potential of large-volume PTV injection was studied for the analysis of triazine herbicides in water samples. Direct water
injection and in-vial extraction were described and compared. Detection limits were between 0.01–0.02 μg L−1 and relative standard deviations were <9%. Both methods are suitable for the analysis of triazines at ppt-level, although
in-vial extraction is favourable for water samples with relatively large amounts of matrix components. 相似文献
9.
Dr. Christoph Ludwig Teske Dr. Anna-Lena Hansen Prof. Dr. Richard Weihrich Prof. Dr. Lorenz Kienle Marius Kamp Kasper Pieter van der Zwan Prof. Dr. Jürgen Senker Dr. Carsten Dosche Prof. Dr. Gunther Wittstock Prof. Dr. Wolfgang Bensch 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(27):6763-6772
A new preparation route is developed for the synthesis of needle-like crystals of [Au(S2CNH2)2]SCN, which avoids disproportionation of the AuI salt used as a starting material. In the crystal structure, the two crystallographically independent AuIII centers are in a square-planar environment of two S2CNH2 ligands. The Hirshfeld surface analysis reveals the presence of noncovalent intermolecular S⋅⋅⋅S interactions, which are essential for the spatial arrangement of the molecules. Density functional theory (DFT) calculations including dispersion and damping corrections result in a unit cell volume very close to the value determined experimentally. Thermal decomposition in an inert atmosphere generates black needles with lengths of up to 500 μm. X-ray powder diffraction and pair distribution function analyses demonstrate that the needles are composed of nanosized crystals with a volume-weighted average domain size of 20(1) nm. According to results of X-ray photoemission experiments, the black needles are covered by a nitrogen-rich carbon nitride with composition near (CN)2N. 13C solid-state NMR investigations indicate that two different carbon species are present, with signals corresponding well to heptazine units as in melon and triazine units as in poly(triazin imide) type compounds. Scanning transmission electron microscopy tomography evidences that the needles are composed of slightly elongated nanoparticles. 相似文献
10.
In this paper, we provide tight estimates for the divisor class number of hyperelliptic function fields. We extend the existing methods to any hyperelliptic function field and improve the previous bounds by a factor proportional to with the help of new results. We thus obtain a faster method of computing regulators and class numbers. Furthermore, we provide experimental data and heuristics on the distribution of the class number within the bounds on the class number. These heuristics are based on recent results by Katz and Sarnak. Our numerical results and the heuristics imply that our approximation is in general far better than the bounds suggest.