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41.
The aim of this study was to determine whether [131I]apigenin is a powerful and discrimination infection from inflammation for scintigraphic imaging. The study was carried out in inflamed rats with Staphylococcus aureus (S. aureus) and sterile inflamed rats with turpentine oil. Biodistribution study of [131I]apigenin was performed in the rats. Apigenin was labeled with 131I by iodogen method. Obtained [131I]apigenin with high yield (98%) was injected i.v. to both group rats. The results were expressed as the percent uptake of injected dose per gram of organ (%ID/g), the bacterial infected and sterile inflamed muscles. Binding of [131I]apigenin to the infected thigh muscle (target muscle = T) and normal thigh muscle (non-target muscle = NT) ratio (T/NT = 4.51 at 15 min) was higher than binding to bacterial inflamed muscle (T/NT = 2.25 at 15 min) of rats. [131I]apigenin showed good localization in both inflamed tissues. This uptake in the sterile inflamed tissue is higher than bacterial infected tissue. [131I]apigenin might be useful for imaging of inflamed tissues. However, it is not discriminate sterile inflamed tissue from bacterial infected tissue.  相似文献   
42.
Ultraviolet light induced high resolution optical absorption spectra and resonance coherent fluorescence of spectroscopically pure fused silica have been studied, due to their potential applications in optoelectronics and laser flash spectroscopy for laboratory use, for optical fibers and for power optics for lasers. Ultraviolet discrete absorption spectra and resonance coherent fluorescence were recorded photographically between 200 and 260 nm. Resonance discrete and coherent fluorescence (i.e. lasing effect) were observed in the 250–255 nm band at room temperature by high photon flux excitation spectroscopy.  相似文献   
43.
B-Type delayed fluorescence of 1,2,3,4-dibenzanthracene in PMMA was experimentally observed for the first time. Dibenzanthracene molecules were exerted in a two-step process. In the first step, an excited singlet S1 is created, which undergoes intersystem crossing to T1 then T-T absorption creates an excited triplet dibenzanthracene molecule, which returns to the first exerted singlet level by intersystem crossing. The recreated first excited singlet of dibenzanthracene decays back to the ground state by emitting this new type of delayed fluorescence.  相似文献   
44.
The results of the elastic scattering of 6He+12C systemat E Lab = 18 MeV by using the barrier and internal wave decomposition of the S-matrix element within the framework of the WKB method are presented. This is the first detailed study for the interaction of the exotic 6He nucleus on different stable nuclei by using a semiclassicalmethod. In this paper, we show that in order to obtain the elastic scattering cross section of the 6He+12C systemat energies close to the Coulomb barrier, it is vitally important to take into account the inner complex turning points in the calculations and the tunneling effects play a crucial role to explain the experimental data. The semiclassical results are compared with the experimental data as well as the quantum-mechanical one.  相似文献   
45.
New phthalonitrile compound with Schiff base, carbothioamide and thiazole moieties as substituents and its corresponding metal-free and metallophthalocyanines (Zn(II), Ni(II), Co(II), and Cu(II)) were synthesized and characterized for the first time. The solubilities of these novel phthalocyanines were high in organic solvents. The redox properties of the compounds have been researched by cyclic voltammetry, square wave voltammetry, controlled-potential coulometry and in situ spectroelectrochemistry in dimethylsulfoxide. The compounds displayed metal and/or phthalocyanine ring-based, generally reversible or quasi-reversible reduction and oxidation processes. The effect of aggregation on the redox behavior of these complexes was also discussed. In general, decreased intensity and broadening in the main Q absorption band and the appearance of a new blue-shifted band confirmed the presence of H-type aggregates in the solutions of the complexes 4, 6 and 8 in DMSO/TBAP. The color changes associated with the redox processes and electrogenerated anionic and cationic redox species were also recorded with in situ electrocolorimetric measurements. In situ UV–vis spectral and associated color changes monitored during the reduction processes of the complexes suggested their applicability in the fields of the electrochemical technologies.  相似文献   
46.
A number of photophysical properties of three different types of rubreneperoxides have been measured experimentally by flash spectroscopy technique, including the two-photon absorption, fluorescence, delayed fluorescence and temperature dependent triplet-triplet absorption spectra. Excited singlet and triplet state lifetimes are temperature dependent. Lowest triplet state lifetimes were measured from 77 K to 50 degrees C. Experimental observations showed that as we decreased the temperature of rubreneperoxides, most of the molecules migrate to the lowest vibrational and rotational energy levels of the ground electronic state. Similar migration is also observed for the lowest triplet state. Therefore at 77 K, we can get the clean absorption an emission spectra and decay curves for the lowest triplet state. At 50 degrees C, due to the P- and/or E-type of delayed fluorescences, decay of T(1) state, in other words disappearance of the T(1) state is becoming faster than at low temperature (below room temperature).  相似文献   
47.
Garnets doped with Nd+3 have attracted extensive interests because of their applications in solid-state lasers, as well as upconversion luminescence and magneto-optical and magnetic properties. Usually, these properties are closely related to the local structures and properties of the Nd+3 impurities in the hosts. Since information about electronic states and local structures of the impurity Nd+3 in the garnets would be helpful to the understanding of the properties of these materials, theoretical investigations on the specific heat functions and the local structures for these Nd+3 centers are of significance.  相似文献   
48.
Crystallography Reports - 2-Chloro-3-((3-(trifluoromethyl)phenyl)amino)naphthalene-1,4-dione (1) and 2-chloro-3-((4-(trifluoromethyl)phenyl)amino)naphthalene-1,4-dione (2) were obtained according...  相似文献   
49.
Two dimensional solution of the Schr?dinger equation for the Kratzer potential with and without the presence of a constant magnetic field is investigated within the framework of the asymptotic iteration method. The energy eigenvalues are analytically obtained for the absence of the magnetic field case. However, in the presence of a constant magnetic field, the energy eigenvalues are calculated numerically using the same method. The results obtained by using different Larmor frequencies and potential parameters are compared with the results of the absence of the magnetic field case (ω L = 0). Effect of the magnetic field on the energy eigenvalues of the Kratzer potential is precisely presented.  相似文献   
50.
We present the elastic scattering of the 6He+208Pb and the 6He+197Au systems at the laboratory energy of E lab=27 MeV within the framework of the McIntyre parametrization, and systematically investigate χ 2/N analysis of both systems to obtain an excellent agreement between the theoretical results and the experimental data. We find large diffusivity parameters indicating long range absorption mechanisms. We also show that both systems lack both the nuclear and the Coulomb rainbow scattering for obtained S-matrix parameters.  相似文献   
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