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951.
952.
P. A. Levene und F. W. Bieber 《Fresenius' Journal of Analytical Chemistry》1922,61(12):476-477
Ohne Zusammenfassung 相似文献
953.
954.
E. L. Kristallovich A. G. Eshimbetov N. D. Chuvylkin L. I. Belen'kii Kh. M. Shakhidoyatov 《Chemistry of Natural Compounds》2003,39(5):495-500
The principal types of electronic transitions in absorption spectra of deoxyvasicinone and its 6-amino- and 6-nitro-derivatives were determined by analyzing the electron-density distributions in excited states calculated using ZINDO/S. 相似文献
955.
956.
Christian J. -F. Dupraz Patrick Nickels Udo Beierlein Wendy U. Huynh Friedrich C. Simmel 《Superlattices and Microstructures》2003,33(5-6):369
This paper provides an overview of recent research developments in the field of nanoelectronics with organic materials such as carbon nanotubes and DNA-templated nanowires. Carbon nanotubes and gold electrodes are chemically functionalized in order to contact carbon nanotubes by self-assembly. The transport properties of these nanotubes are dominated by charging effects and display clear Coulomb blockade behaviour. A different approach towards nanoscale electronics is based on the molecular recognition properties of biomolecules such as DNA. As an example, DNA is stretched between electrodes using a molecular combing technique. A two-step metallization procedure leads to the formation of highly conductive gold nanowires. 相似文献
957.
F. Prez-Willard C. Sürgers H. Von Lhneysen P. Pfundstein 《Physica E: Low-dimensional Systems and Nanostructures》2004,22(4):872-880
The electronic transport through nanostructured bismuth nanobridges has been investigated at low temperatures (T<2 K) and in magnetic fields B up to 8.5 T. The samples show reproducible resistance fluctuations as a function of B, superimposed on a large magnetoresistance of up to 50%. In addition, time-dependent resistance fluctuations in zero magnetic field demonstrate the presence of bistable scatterers in the constriction region of our samples, which are described by two-level systems. Their dynamics are shown to be sensitive to subtle modifications of the static scatterer configuration in their vicinity, which cannot be detected in the sample magnetofingerprint. 相似文献
958.
Various antimonate compounds are well known as important inorganic ion exchangers, since they resist radiation and chemical degradation and also exhibit selectivities towards different cations. Ceric, silicon, titanium and ferric antimonates were prepared as inorganic ion exchangers. Characterization of these materials has been described using different techniques, including thermal analysis, surface area measurements, X-ray diffraction and IR-spectroscopy. In batch distribution experiments the influence of HNO3 molarity and Mo concentration for Mo sorption on different matrices is described in terms of their retention capacities and distribution coefficients.The selectivities of these exchangers towards molybdenum are in the order: CeSb > SiSb > FeSb > TiSb. 相似文献
959.
Yu. A. Kumzerov L. S. Parfen’eva I. A. Smirnov H. Misiorek J. Mucha A. Jezowski 《Physics of the Solid State》2003,45(1):57-60
The thermal conductivity of crystalline chrysotile asbestos made up of hollow tubular Mg3Si2O5(OH)4 filaments is measured in the range 5–300 K. The paper discusses the possibility of using this material in studies of the thermal conductivity of thin filaments of metals and semiconductors incorporated into the channels of crystalline chrysotile asbestos tubes. 相似文献
960.
Times of longitudinal T
1b
and transverse T
2b
magnetic relaxation of hexane and decane molecules in micropores of ZSM-5 silicalite were measured as functions of the content of these liquid n-alkanes in zeolite and of temperature. The stepwise changes in the T
1b
and T
2b
times were revealed in the region of 8% content of hydrocarbons. The observed changes in the concentration and temperature dependences of T
1b
and T
2b
times are explained by the rearrangement of silicalite crystal lattice under the action of adsorbed molecules. 相似文献