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271.
Heinz LÜneburg 《Archiv der Mathematik》1984,42(2):139-144
Ohne Zusammenfassung 相似文献
272.
Summary In this paper we consider the transformation of measure induced by a not-necessarily-invertible perturbation of the identity. The Radon-Nikodym density for the image of the Wiener measure and the associated Girsanov-type density are derived. An application of these results yields an extension of the degree theorem. 相似文献
273.
274.
Our earlier methods of interpretation of the resonances in ion-ion scattering (such as 12C + 12C, 12C + 16O, or 16O + 16O where they appear both experimentally and via optical-model calculations) in terms of nuclear surface waves are applied to the case of α-40Ca scattering. The optical-model resonance results of Brink et al. are here extended in order to render them suitable for a surface-wave picture as well. Recent experimental results on 12C + 12C scattering are used to demonstrate the existence of surface waves of both Rayleigh and whispering gallery type in this system. 相似文献
275.
Biljana Šmit Biljana Petrović Sofija Sovilj Dragan Čanović Živadin D. Bugarčić 《Monatshefte für Chemie / Chemical Monthly》2008,139(10):1197-1202
The reactions of cisplatin with nizatidine and ranitidine were studied in D2O at pD 7.4 and 298 K by means of 1H NMR spectroscopy. The second order rate constants, k
2, for the reaction of cisplatin with nizatidine is (2.71 ± 0.11) × 10−4 M
−1 s−1, and for the reaction with ranitidine (6.72 ± 0.17) × 10−4 M
−1 s−1. The reactions of nizatidine and ranitidine were also studied with other Pd(II) and Pt(II) complexes. The set of the complexes
was selected because of their difference in reactivity, steric hindrance, and binding properties.
Correspondence: Prof. Dr. Živadin D. Bugarčić, Faculty of Science, University of Kragujevac, Radoja Domanovića 12, 34000 Kragujevac,
Serbia. 相似文献
276.
Thermal stability of clinoptilolite rich mineral from Western Anatolia, Turkey and its Ag-exchange forms was investigated.
Parent mineral of different sizes were heated up to 1000°C with heating rate of 2 and 10°C min-1 using differential thermal analyzer (DTA) and thermogravimetric analyzer (TG). Ag exchange was conducted both in conventional
constant temperature waterbath and microwave at 40, 60 and 80°C. The exchanged minerals were then characteized by scanning
electron microscopy (SEM), X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), DTA and TG.
The particle size and heating rate do not have significant effect on the thermal behavior of the parent mineral and no structural
changes were observed with Ag exchange, only decomposition temperature was lowered. It was finally concluded that, Ag-exchanged
clinoptilolite rich minerals were less thermally stable compared to parent mineral that does not affect their use for possible
applications. 相似文献
277.
We consider a nonoscillatory half-linear second order differential equation (*) $$ (r(t)\Phi (x'))' + c(t)\Phi (x) = 0,\Phi (x) = \left| x \right|^{p - 2} x,p > 1, $$ and suppose that we know its solution h. Using this solution we construct a function d such that the equation (**) $$ (r(t)\Phi (x'))' + [c(t) + \lambda d(t)]\Phi (x) = 0 $$ is conditionally oscillatory. Then we study oscillations of the perturbed equation (**). The obtained (non)oscillation criteria extend existing results for perturbed half-linear Euler and Euler-Weber equations. 相似文献
278.
Dr. Elif Akhuseyin Yildiz Dr. Ebru Yabaş Prof. Fazlı Sözmen Dr. Yasemin Bozkurt Dr. Ahmet Karatay Prof. Bahadir Boyacioglu Prof. Hüseyin Ünver Dr. Ayhan Elmali 《Chemphyschem》2023,24(5):e202200735
Borondipyrromethene (BODIPY) chromophores are composed of a functional-COOH group at meso position with or without a biphenyl ring, and their compounds with heavy iodine atoms at −2, −6 positions of the BODIPY indacene core were synthesized. The photophysical properties of the compounds were studied with steady-state absorption and fluorescence measurements. It was observed that the absorption band is significantly red-shifted, and fluorescence signals are quenched in the presence of iodine atoms. In addition to that, it was indicated that the biphenyl ring does not affect the spectral shifting in the absorption as well as fluorescence spectra. In an attempt to investigate the effect of π-expanded biphenyl moieties and heavy iodine atoms on charge transfer dynamics, femtosecond transient absorption spectroscopy measurements were carried out in the environment of the tetrahydrofuran (THF) solution. Based on the performed ultrafast pump-probe spectroscopy, BODIPY compounds with iodine atoms lead to intersystem crossing (ISC) and ISC rates were determined as 150 ps and 180 ps for iodine BODIPY compounds with and without π-expanded biphenyl moieties, respectively. According to the theoretical results, the charge transfer in the investigated compounds mostly appears to be intrinsic local excitations, corresponding to high photoluminescence efficiency. These experimental findings are useful for the design and study of the fundamental photochemistry of organic triplet photosensitizers. 相似文献
279.
Aksoy MS 《Chemical & pharmaceutical bulletin》2008,56(6):771-774
The chromium(III) complex species formed, in acidic and basic solutions at 25.0+/-0.1 degrees C, between Cr(III) and 2,3-dihydroxynaphthalene-6-sulfonic acid (2,3-DHN-6-SA, H(2)L(2-)) and 4,5-dihydroxynaphthalene-2,7-disulfonic acid (4,5-DHN-2,7-DSA, H(2)L(-)) were determined. Over the acidic pH range, the coordination of 2,3-DHN-6-SA and 4,5-DHN-2,7-DSA to Cr(III) in 1 : 1 mole ratio occurs, and CrL and CrL(-) type complexes are formed. At near neutral pH, CrL(OH)(-) and CrL(OH)(2-) type hydroxo complexes are formed. The acid-dissociation constants of ligands and the formation constants of chromium(III) complexes were determined in 0.1 m KNO(3) ionic medium by potentiometric titration using the BEST computer program. Thus, the removing capacities of these ligands could be examined by calculating the equilibrium concentration of Cr(III) that exists in the discharge water of various industries since Cr(III) ions are the main pollutants present during waste water treatment in our city, Bursa. 相似文献
280.