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991.
992.
U. Hardebusch W. Gerhardt J. S. Schilling 《Zeitschrift für Physik B Condensed Matter》1985,60(2-4):463-470
Previous studies of the magnetic susceptibility of a Ag-3 at.% Mn spin-glass under high pressure are extended to include the systems Au-3at.% Mn, Cu-3at.% Mn and Au-3at.% Fe. In all four alloys the spin-glass freezing temperatureT
0 increases with pressure, yielding the volume dependences lnT
0/ lnV=–3.6±0.4, –4.1±0.6, –2.1±0.4 and –1.64±0.25, respectively. These results give information about the nature of the interaction mechanisms responsible for the spin-glass freezing phenomena. The pressure dependence of the Curie temperature of ferromagnetic Au-20at.% Fe was also studied.Dedicated to B. Mühlschlegel on the occasion of his 60th birthday 相似文献
993.
The temperature dependence of the light intensity emitted by the plasma layer generated at the surface of triglycine sulphate samples at alternating polarization has been investigated. The changes of intensity of the emitted light were found to correspond to the changes of the dielectric constant of triglycine sulphate. This phenomenon can be used to determine the ferroelectric phase-transition temperature and to investigate the changes of the dielectric constant of ferroelectrics by studying the light of plasma generated at their surfaces. 相似文献
994.
M. E. Umstead S. A. Lloyd J. W. Fleming M. C. Lin 《Applied physics. B, Lasers and optics》1985,38(4):219-224
The reaction of NO2 with isobutane, induced by 488 nm laser radiation, to form 2-nitro-2-methylpropane has been investigated and the results computer-modeled according to two possible reaction mechanisms. The first scheme involves the direct abstraction of H from isobutane by vibronically excited NO2 (NO
2
*
), and the second, abstraction by an intermediate NO3 radial produced by NO
2
*
+NO2. The modeling results strongly support the NO
2
*
scheme as the dominant reaction mechanism. 相似文献
995.
The intense native fluorescence of pimozide is reported. It is due to the benzo-1,3-diazolin-2-one fraction of the molecule, also present in the structurally analogous benperidol molecule. The fluorescence intensity is nearly independent of solvent acidity. This substance can be determined in oral preparations by its native fluorescence in diethyl ether (lambda(EXC) = 290 nm. lambda = 319 nm) with a detection limit of 0.01 mug/ml. 相似文献
996.
A selective gas chromatographic detector for polynuclear aromatics based on ultraviolet fluorescence
A vapor-phase fluorescence detector for the analysis of mixtures of polynuclear aromatic ring systems has been developed. This system utilizes wide bandpass excitation and wide band emission filters, thus increasing sensitivity and decreasing the complexity of previously designed instruments. The sensitivity of the detector has been demonstrated to be at the nanogram level with reasonable precision. 相似文献
997.
W. Dölling K. Kischkies F. Heinemann H. Hartung 《Monatshefte für Chemie / Chemical Monthly》1993,124(6-7):707-719
Summary The new alkyl 2-(2-oxo-benzazoline-3-yl)-3-hydroxy dithiocrotonates and dithiocinnamates4 and the corresponding ketene dithioacetals2 and5 are obtained by dithiocarboxylation of the 3-acceptormethyl substituted benzazoline-2-ones1 or3. Alkylation at room temperature gives compounds4 whereas at higher alkylation temperature2 or5 are formed. The results of X-ray analyses performed for methyl 3-hydroxy-p-chloro-dithiocinnamate4d and of N-[1-(4-chloro-benzoyl)-2,2-bis(methylthio)-vinyl]-benzothiazoline-2-one5e are discussed. 相似文献
998.
999.
One-Bond P? P Coupling Constant of Diphosphate Anions The coupling constant 1JPP of diphosphate anions depends upon the electronegativities of the substituents at phosphorus. The simple linear relationship which has been established also holds for other P? P compounds involving tetra-coordinate phosphorus, with the exception of compounds with bulky substituents. 相似文献
1000.