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1.
A new approach to identify the independent amplitudes along with their partial wave multipole expansions, for photo-and electro-production
is suggested, which is generally applicable to mesons with arbitrary spin-parity. These amplitudes facilitate direct identification
of different resonance contributions.
相似文献
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We have carried out accurate generalized-gradient-corrected fully-relativistic full-potential calculations for Sr1−xCaxRuO3 (x=0, 0.25, 0.5, 0.75, and 1) in para-, ferro-, and A-, C-, and G-type antiferromagnetic configurations. We have performed electronic structure calculations for the experimentally observed orthorhombic structure as well as the hypothetical cubic structure. Our results are analyzed with the help of total, site-, spin-, and orbital-projected density of states. The total-energy studies show that CaRuO3 stabilizes in the G-type antiferromagnetic state. The octahedral tilting owing to the relatively small radius of Ca2+ leads to weak hybridization between Ru 4d and O 2p. This weak hybridization along with exchange splitting causes a pseudogap-like feature close to the Fermi level, which should stabilize G-type antiferromagnetic ordering in CaRuO3. However, powder neutron diffraction data on CaRuO3 taken at 8 and do not show any magnetic peaks, implying that CaRuO3 exhibits a spin-glass-like state with dominant short-range antiferromagnetic interaction. The calculated magnetic ground state of Sr1−xCaxRuO3 is found to be consistent with the experimental findings. We have also calculated optical spectra as well as X-ray and ultra-violet photoemission spectra and Ru and O K-edge X-ray absorption spectra for G-type CaRuO3 and found good agreement with available experimental spectra. 相似文献
4.
An efficient and concise approach to the synthesis of the macrolide core of the cryptophycins has been developed. A novel macrolactonization utilizing a reactive acyl-beta-lactam intermediate incorporates the beta-amino acid moiety within the 16-membered macrolide core. This modular approach, involving a cyanide-initiated acyl-beta-lactam ring opening followed by cyclization, was successfully applied to the total synthesis of cryptophycin-24. The strategy was also used in an efficient synthesis of the 6,6-dimethyl-substituted dechlorocryptophycin-52. In this case, the cyanide-initiated ring opening of the bis-substituted 2-azetidinone followed by macrolactonization was achieved through a catalytic process. 相似文献
5.
Summary 2-Aminopyridine reacts with acetylacetone in the presence of VOII, MnII, FeII, CoII, NiII, and CuII metal salts to give complexes of the type [VO(Ap2ac)2X]X and [M(Ap2ac)2X2] where (Ap2ac) is the ligand formedin situ. The complexes are characterised as distorted octahedral by analyses, conductance, molecular weight, magnetic, electronic and i.r. spectral studies. The i.r. studies reveal that two molecules of aminopyridine are joined by a molecule of acetylacetone through a three carbon atom bridge and that the ligand coordinates through the azomethine and imino nitrogen atoms, whereas pyridine does not take part in coordination. The electronic spectra have been interpreted and tentative assignments are made. In the far i.r. spectra, various metal ligand vibrations are observed and discussed. Attempts to carry out electrophilic substitutions in the complexes failed. 相似文献
6.
Chary KV Sagar GV Naresh D Seela KK Sridhar B 《The journal of physical chemistry. B》2005,109(19):9437-9444
A series of copper catalysts supported on TiO2-ZrO2 with copper loading varying from 1.0 to 21.6 wt % were prepared by a wet impregnation method. The catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy, electron spin resonance (ESR), temperature programmed reduction (TPR), and Brunauer-Emmett-Teller specific surface area measurements. Copper dispersion and metal area were determined by N2O decomposition by the passivation method. XRD results suggest that the copper oxide is present in a highly dispersed amorphous state at copper loadings <16.8 wt % in the sample and as a crystalline CuO phase at higher Cu loadings. Copper dispersion increases with Cu loading up to 5.1 wt % and levels off at higher loadings. The XPS peak intensity ratios of Cu 2p(3/2)/Ti 2p(3/2) and Cu 2p(3/2)/Zr 3d(5/2) were compared with the copper dispersion calculated from N2O decomposition. ESR results suggest the presence of two types of copper species on the TiO2-ZrO2 support. TPR profiles reveal the presence of highly dispersed copper oxide at lower temperatures and bulk CuO at higher temperatures. The catalytic properties were evaluated for the vapor-phase dehydrogenation of cyclohexanol to cyclohexanone and related to the dispersion of Cu on TiO2-ZrO2. 相似文献
7.
Dighe Vidya V. Pathak Gayatri M. Tulpule Ketan M. Gokarn Vijay N. 《平面色谱法杂志一现代薄层色谱法》2007,20(3):179-182
JPC – Journal of Planar Chromatography – Modern TLC - A sensitive high-performance thin-layer chromatographic method has been established for quantification of apigenin in dried root... 相似文献
8.
Doiphode Vidya Vairale Priti Sharma Vidhika Waghmare Ashish Punde Ashvini Shinde Pratibha Shah Shruti Pandharkar Subhash Hase Yogesh Aher Rahul Nair Shruthi Jadkar Vijaya Bade Bharat Prasad Mohit Rondiya Sachin Jadkar Sandesh 《Journal of Solid State Electrochemistry》2021,25(6):1835-1846
Journal of Solid State Electrochemistry - Herein, we report the synthesis of ZnO nanorod films onto FTO (fluorine-doped tin oxide) substrates using the solution-processed electrodeposition method.... 相似文献
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A series of CuO/Al(2)O(3)-ZrO(2) catalysts with Cu loadings varying from 1.0 to 20 wt % were prepared and characterized by X-ray diffraction (XRD), temperature-programmed reduction (TPR), temperature-programmed desorption (TPD) of CO(2) and NH(3), electron spin resonance (ESR), and Brunauer-Emmett-Teller surface area measurements. The dispersion and metal area of copper were determined by the N(2)O decomposition method. XRD results suggest that the copper oxide is present in a highly dispersed amorphous state at copper loadings < 10 wt % and as a crystalline CuO phase at higher Cu loadings. ESR results suggest the presence of two types of copper species on the Al(2)O(3)-ZrO(2) support. TPR results suggest well-dispersed copper oxide species at low Cu loadings and crystalline copper oxide species at high Cu loadings. Well-dispersed copper oxide species were reduced more easily than large copper oxide species by H(2). The results of CO(2) TPD suggest that the basicity of the catalysts was found to increase with an increase of copper loading up to 5.0 wt % and decreases with a further increase of copper loading. The results of NH(3) TPD suggest that the acidity of the catalysts was found to decrease with an increase of copper loading up to 5.0 wt % and increases with a further increase of copper loading. The catalytic properties were evaluated for the vapor-phase dehydrogenation of cyclohexanol to cyclohexanone and correlated with the results of CO(2) TPD measurements and the dispersion of Cu on the Al(2)O(3)-ZrO(2) support. 相似文献