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81.
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Niels Olaf Østerberg Torben Smith Sørensen Jørgen Birger Jensen 《Journal of Electroanalytical Chemistry》1981,119(1):93-108
The emf of electrochemical cells containing various sorts of salt bridges between various concentrations has been measured. The net diffusion potential over a salt bridge has been treated theoretically. An expression to calculate the net diffusion potential has been derived and tested on values estimated from the emf measurements. A merit factor has been calculated for a saturated KCl bridge separating two HCl solutions and compared with the merit factor estimated from emf measurements on the cell:Pt|Ag|AgCl, HCl(c1)|KCl(sat)|HCl(c2), AgCl|Ag|Pt The practical performance of two commonly used reference electrodes with salt bridges has been tested on emf measurements on KBr solutions. 相似文献
84.
We report on a matter wave interferometer realized with entangled pairs of trapped 87Rb atoms. Each pair of atoms is confined at a single site of an optical lattice potential. The interferometer is realized by first creating a coherent spin superposition of the two atoms and then tuning the interstate scattering length via a Feshbach resonance. The selective change of the interstate scattering length leads to an entanglement dynamics of the two-particle state that can be detected in a Ramsey interference experiment. This entanglement dynamics is employed for a precision measurement of atomic interaction parameters. Furthermore, the interferometer allows us to separate lattice sites with one or two atoms in a nondestructive way. 相似文献
85.
The fluorescence of thiazole orange as artificial base in PNA was investigated in a nearest neighbour analysis; library-to-library hybridisation allowed the identification of probe sequences suitable for homogeneous DNA detection. 相似文献
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The variability of carbon-carbon single bonds by steric and electronic effects is probed by DFT calculations of sterically crowded bicyclo[1.1.0]butanes and their radical cations. The interplay of sterics and electronics on the gradual weakening and breaking of bonds was studied by investigating bridgehead substitution in 1,3-di-tert-butylbicyclo[1.1.0]butane and 2,2',4,4'-tetramethyl-1,3-di-tert-butylbicyclo[1.1.0]butane and geminal substitution in 2,2'-di-tert-butylbicyclo[1.1.0]butane and 2,2',4,4'-tetra-tert-butylbicyclo[1.1.0]butane. Bridgehead substitution leads to a lengthening of the central bond, whereas bisubstitution on the geminal carbon leads to a shortening of this bond due to a Thorpe-Ingold effect. Although the character of the central bond can be modulated by substitution and electron transfer over a range of 0.35 A, the state forbidden ring planarization does not occur. Sterically crowded bicyclo[1.1.0]butane radical cations are therefore promising candidates for the investigation of extremely long carbon-carbon single bonds. 相似文献
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Olaf Tamaschke 《Mathematische Zeitschrift》1961,75(1):211-214
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