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1.
Herwig G. Winkler Hagen T. Spath Prof. Dr. Karl Torkar 《Monatshefte für Chemie / Chemical Monthly》1975,106(2):535-545
The phase diagrams of the systems CsN3/Zn(N3)2 and KN3/Zn(N3)2 have been obtained employing the microscopic technique ofL. Kofler andA. Kofler. Within the system CsN3/Zn(N3)2 three eutectics at 148°C, 142°C, and 210°C were found. Besides Cs2Zn(N3)4, melting incongruently in the interval 153°C to 170°C, there exist two further compounds of the most probable composition Cs3Zn2(N3)7 and CsZn2(N3)5, melting congruently at 170°C and 210°C, resp. In the system KN3/Zn(N3)2 there exist two eutectics at 203°C and 172°C and two compounds, one of them, i.e. K2Zn(N3)4, melting congruently at 206°C, the other one, with composition KZn3(N3)7 or KZn4(N3)9, melting incongruently at 210°C.
Mit 8 Abbildungen
Herrn Professor Dr.Heribert Grubitsch zum 70. Geburtstag gewidmet. 相似文献
Mit 8 Abbildungen
Herrn Professor Dr.Heribert Grubitsch zum 70. Geburtstag gewidmet. 相似文献
2.
ALBERT VAN DE VORST 《Photochemistry and photobiology》1971,13(4):321-336
Abstract— –The photosensitization of amino acids by proflavine is studied using the technique of electron spin resonance spectroscopy. The analysis of the line shape as a function of the incident microwave power (both in the presence and absence of oxygen) and the dependence of the numbers of free radicals on the intensity of the incident light allow one to suggest that two types of radicals are formed. One is formed by a biphotonic process, the nature of the radicals being the same as in the case of ionising radiation, while the other is probably the RO2 radical formed as a result of photodynamic action. 相似文献
3.
4.
It is shown that azulenium cations in the first electronically excited state S1 are stronger acids than in the ground state S0. Their apparent pK″*, obtained from the H0-dependence of the quenching of the azulenium cation S1 → S0 fluorescence does not correspond to a true acid-base equilibrium in the electronically excited state S1. The pK″* values are kinetically controlled, the rate of reprotonation of azulene in the S1 state being too low to compete with the internal conversion to S0. 相似文献
5.
H. Hagen 《Journal of Geometry》1983,21(1):157-163
In this paper we investigate (k+1)-dimensional generalized ruled surfaces generated by a one-parameter family of k-dimensional linear subspaces of the n-dimensional Euclidean space \(\mathbb{E}^n \) . 相似文献
6.
7.
Lateral diffusion measurements, most commonly accomplished through Fluorescence Photobleaching Recovery (FPR or FRAP), provide
important information on cell membrane molecules' size, environment and participation in intermolecular interactions. However,
serious difficulties arise when these techniques are applied to weakly expressed proteins of either of two types: fusions
of membrane receptors with visible fluorescent proteins or membrane molecules on autofluorescent cells. To achieve adequate
sensitivity in these cases, techniques such as interference fringe FPR are needed. However, in such measurements, cytoplasmic
species contribute to the fluorescence recovery signal and thus yield diffusion parameters not properly representing the small
number of surface molecules. A new method helps eliminate these difficulties. High Probe Intensity (HPI)-FPR measurements
retain the intrinsic confocality of spot measurements to eliminate interference from fluorescent cytoplasmic species. However,
HPI-FPR methods lift the previous requirement that FPR procedures be performed at probe beam intensities low enough to not
induce bleaching in samples during measurements. The high probe intensities now employed provide much larger fluorescence
signals and thus more information on molecular diffusion from each measurement. We report successful measurement of membrane
dynamics by this technique. 相似文献
8.
We present a new snapshot technique for performing spectrally resolved Mueller matrix polarimetry. The basic approach is an extension of the channeled spectropolarimetry technique, employing frequency-domain interferometry to encode polarization information into modulation of the spectrum. 相似文献
9.
A. Priem P. J. M. van Bentum W. R. Hagen E. J. Reijerse 《Applied magnetic resonance》2001,21(3-4):535-548
Fe(III) and Gd(III) ions in α-alumina (A12O3) exhibit spin states ofS = 5/2 andS = 7/2 respectively. The magnitude of the zero-field interaction (ZFI) (D = 0.10?0.15 cm?1) gives rise to an inter Kramers doublet splitting in the same order of magnitude as the X-band electron paramagnetic resonance (EPR) quantum (0.3 cm?1). It is demonstrated that through a careful step-by-step analysis and spectral simulation of EPR spectra taken at D-band (130 GHz), Q-band (35 GHz), and X-band (9 GHz) at room temperature, the (relative) sign and magnitude of the ZFI parameters, b 2 0 , b 4 0 , and b 4 3 , can be reliably estimated. 相似文献
10.
Hagen Kleinert 《General Relativity and Gravitation》2000,32(5):769-839
I explain the geometric basis for the recently-discovered nonholonomic mapping principle which permits deriving laws of nature in spacetimes with curvature and torsion from those in flat spacetime, thus replacing and extending Einstein's equivalence principle. As an important consequence, it yields a new action principle for determining the equation of motion of a free spinless point particle in such spacetimes. Surprisingly, this equation contains a torsion force, although the action involves only the metric. This force makes trajectories autoparallel rather than geodesic, as a manifestation of inertia. A generalization of the mapping principle transforms path integrals from flat spacetimes to those with curvature and torsion, thus playing the role of a quantum equivalence principle. This generalization yields consistent results only for completely antisymmetric or for gradient torsion. 相似文献