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411.
采用溶胶-凝胶法分别在K9玻璃、单晶硅和石英玻璃基底上制备了纳米TiO2和SiO2薄膜。利用SEM、UV-Vis及反射式椭圆偏振光谱仪对薄膜的微观结构及光学特性进行了表征和分析。结果表明:3种基底中, 单晶硅基底上TiO2和SiO2薄膜折射率最大;在非晶态K9玻璃和石英玻璃基底上TiO2薄膜折射率和透光率差异较大;SiO2薄膜在非晶态基底上折射率、透光率相近;3种基底上薄膜的折射率和消光系数都有随波长增大而减小的趋势, 同时Cauchy模型能较好的描述单晶硅基底上两种薄膜在400~800 nm波段的光学性能。 相似文献
412.
Discrete (quasi) modules form an important class in module theory, they are studied extensively by many authors. The decomposition theorem for quasidiscrete modules plays an important rule in the better understanding of such modules. In fact, every quasidiscrete module is a direct sum of hollow submodules. Here we introduce some new concepts (weak quasidiscrete, and S 1- and S 2-supplemented modules) which generalize the concept of quasidiscrete module. We show that some of the properties of quasidiscrete modules still hold in the class of weak quasidiscrete modules. We also obtain some properties of weak quasidiscrete modules, which are similar to the properties known for quasidiscrete modules. We introduce the concept of generalized relative projectivity (relative S-projectivemodules), and use it to characterize direct sums of hollowmodules. In fact, relative S-projectivity is an essential condition for direct sums of hollow modules to be weak quasidiscrete modules. 相似文献
413.
In this paper, we define a new generalized difference sequence space involving lacunary sequence. Then, we examine k-NUC property and property (β) for this space and also show that it is not rotund where p = (pr) is a bounded sequence of positive real numbers with pr ≥ 1 for all r ∈ N. 相似文献
414.
415.
Yousef Fazaeli Amir R. Jalilian Mostafa M. Amini Ali Rahiminejad-kisomi Saeed Rajabifar Fatemeh Bolourinovin Sedigheh Moradkhani 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):17-24
[67Ga]labeled tetraphenyl porphyrin ([67Ga]-TPP) was prepared using freshly prepared [67Ga]GaCl3 and tetraphenyl porphyrin (TPPH2) for 30–60 min at 25 °C (radiochemical purity: >97 ± 1% ITLC, >98 ± 0.5% HPLC, specific activity: 13–14 GBq/mmol). Stability
of the complex was checked in final formulation and human serum for 24 h. The partition coefficient was calculated for the
compound (log P 1.89). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies
and SPECT imaging up to 24 h. A detailed comparative pharmacokinetic study performed for 67Ga cation and [67Ga]-TPP. The complex is mostly washed out from the circulation through kidneys and can be an interesting tumor imaging/targeting
agent due to low liver uptake and rapid excretion through the urinary tract. 相似文献
416.
417.
Rushdi I. Yousef Martin BetteGoran N. Kalu?erovi? Reinhard PaschkeCui Yiran Dirk SteinbornHarry Schmidt 《Polyhedron》2011,30(12):1990-1996
Potassium dichlorido(l-prolinato)platinate(II), K[PtCl2(l-proH)] (1), and chlorido(dimethyl sulfoxide)(l-prolinato)platinum(II), [PtCl(l-proH)(dmso)] (2), were synthesized by ligand substitution reactions. Both complexes were characterized by 1H, 13C, and 195Pt NMR spectroscopy, elemental analysis, and HR-ESI-MS. The molecular structures of 1 and 2 were determined by single crystal X-ray diffraction, proving bidentate coordinated l-prolinato ligand and SP-4-4 configuration of 2a. With the help of DFT calculations stability of possible isomers of 1 and 2 was studied. A considerable difference in the in vitro cytotoxicity of 1 versus 2a (exchange of one chlorido ligand by dmso) against four human cancer cell lines was found. 相似文献
418.
Pourghaz Y Dongare P Thompson DW Zhao Y 《Chemical communications (Cambridge, England)》2011,47(39):11014-11016
Side-chain functionalized poly(p-phenylene ethynylene)s (PPEs) carrying triazole linkers, amino donors/receptors, and solubilizing groups have been found to yield remarkably high efficiency of fluorescence turn-on sensing for Zn(2+) and Cd(2+) ions in THF, and for H(+) and Cd(2+) ions in water. 相似文献
419.
Mosa AI Emara AA Yousef JM Saddiq AA 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,81(1):35-43
A new series of stable transition metal complexes of the formula M(L)X·S, where M = Cu(II), Ni(II), Co(III), Cr(III) and Fe(III) and L is the deprotonated ligand of 4-hydroxy-coumarin-3-thiocarbohydrazone, X = Cl(-), NO(3)(-) or CH(3)COO(-) and S = H(2)O and/or EtOH. The HL ligand was prepared by the reaction of 3-formyl-4-hydroxy-coumarine with thiocarbohydrazide in the molar ratio 1:1. The HL ligand and its metal complexes were characterized by elemental analysis, (1)H NMR, IR and electronic spectra, and molar conductance and magnetic measurements and thermal gravimetric analysis (TGA). The HL ligand acts as a monobasic tridentate ONS donor in all metal complexes, and coordinated through the phenolic OH, azomethine nitrogen and thione sulfur. Electronic spectra with magnetic moments suggested varieties of geometries around the central metal atoms. Thermal gravimetric analysis indicates that the complexes are stable up to 300°C, and release the uncoordinated and/or coordinated H(2)O/solvent molecules, which is accompanied by a color change. The formed complexes after releasing the solvent were investigated and their structures are suggested to have square planar or octahedral arrangement. Pharmacodynamic of cobalt(III) complex on some biochemical parameters and histological studies in serum and heart tissue in rats have been studied. Although the complexes demonstrated a significant effect at low dose than the high dose, the ligand showed significant good effects in both high and low doses on the biochemical analysis in serum and heart tissue. Cobalt complex was screened in order to evaluate its antifungal activity against the filamentous fungi Aspergillus niger, Aspergillus fumigatus, and Aspergillus flavus, and antibacterial activity against the Candida albicans, Escherichia coli, Klebseilla pneumoniae and Pseudomonas aeruginosa. 相似文献
420.
Nassim Vahidfar Amir R. Jalilian Yousef Fazaeli Ali Bahrami-Samani Davood Beiki Ali Khalaj 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):979-986
Porphyrins are interesting derivatives with low toxicity, tumor avidity and rapid wash-out suggested as potential radiopharmaceuticals in radiolabeled form. In this work, [166Ho] labeled 5,10,15,20-tetrakis(phenyl) porphyrin ([166Ho]-TPP) was prepared using [166Ho]HoCl3 and 5,10,15,20-tetrakis(phenyl)porphyrin (H2TPP) for 12 h at 50 °C (radiochemical purity: >95 ± 2 % ITLC, >99 ± 0.5 % HPLC, specific activity: 0.9–1.1 GBq/mmol). Stability of the complex was checked in final formulation and human serum for 48 h. The partition coefficient was calculated for the compound (log P = 2.01). The biodistribution of the labeled compound in vital organs of wild-type rats was studied using scarification studies and SPECT. A detailed comparative pharmacokinetic study performed for 166Ho cation and [166Ho]-TPP performed up to 24 h. The complex is mostly washed out from the circulation through kidneys and in less extends from the liver. The kidney:blood, kidney:liver and kidney:muscle ratios 4 h post injection were 14, 3.6 and 7.38 respectively. 相似文献