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排序方式: 共有165条查询结果,搜索用时 15 毫秒
91.
Thin films of tin sulphide (SnS) were deposited on tin oxide conducting glass substrates by thermal evaporation technique. The transmission spectrum of the SnS film in the wavelength range from 300 to 1100 nm has been obtained. X-ray diffraction has been used to determine the structure of the films. The film thickness and refractive index have been estimated from the transmission spectra. The results showed that the refractive index of the SnS thin films is thickness independent in the wavelength range 590 ≤ λ ≤ 1100 nm and found to be ~ 1.72. This result indicates that the SnS thin films are homogeneous and isotropic. The energy band gaps were found to be between 1.06 and 1.32 eV, which is in good agreement with literature values. The energy dependence of the obtained refractive index is also investigated. 相似文献
92.
Shankar A. Hallad N. R. Banapurmath T. M. Yunus Khan M. A. Umarfarooq Manzoore Elahi M. Soudagar Anand M. Hunashyal Sandeep V. Gujjar Jayachandra S. Yaradoddi Sharanabasava V. Ganachari Ashraf Elfasakhany Md Irfanul Haque Siddiqui Masood Ashraf Ali 《Molecules (Basel, Switzerland)》2021,26(14)
Epoxy resins, due to their high stiffness, ease of processing, good heat, and chemical resistance obtained from cross-linked structures, have found applications in electronics, adhesives coatings, industrial tooling, and aeronautic and automotive industries. These resins are inherently brittle, which has limited their further application. The emphasis of this study is to improve the properties of the epoxy resin with a low-concentration (up to 0.4% by weight) addition of Multi-Walled Carbon Nanotubes (MWCNTs). Mechanical characterization of the modified composites was conducted to study the effect of MWCNTs infusion in the epoxy resin. Nanocomposites samples showed significantly higher tensile strength and fracture toughness compared to pure epoxy samples. The morphological studies of the modified composites were studied using Scanning Electron Microscopy (SEM). 相似文献
93.
94.
Yunus Çelik Esat Bozkurt İbrahim Uçar Bünyamin Karabulut 《Journal of Physics and Chemistry of Solids》2012,73(8):1010-1016
The crystal structures of [Co(4-acpy)2(H2O)4] (sac)2 (1) and [Zn(4-acpy)2(H2O)4] (sac)2 (2) (4-acpy: 4-acetylpyridine, sac: saccharinate) complexes have been investigated by X-ray diffraction techniques. The magnetic environments of Cu2+ doped [Co(4-acpy)2(H2O)4] (sac)2 and [Zn(4-acpy)2(H2O)4] (sac)2 complexes have been identified by electron paramagnetic resonance (EPR) technique. Principal values of g and hyperfine tensors are determined and the ground state wave functions of Cu2+ ions are obtained using EPR parameters. The vibrational spectra were also discussed in relation with the other compounds containing saccharinate and 4-acetylpyridine complexes. 相似文献
95.
Guney E Kaya Y Yilmaz VT Gumus S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1171-1178
New palladium(II) and platinum(II) complexes of saccharinate (sac) with 2-(2-pyridyl)benzimidazole (pybim) have been synthesized and characterized by elemental analysis and spectroscopic techniques. From the experimental studies, these complexes were formulated as [Pd(pybim)(sac)2] (1), and [Pt(pybim)(sac)2]·4H2O (2). The ground-state geometries of both complexes were optimized using density functional theory (DFT) methods at the B3LYP level. A bidentate pybim ligand together with two N-coordinated sac ligands form the square-planar MN4 coordination geometry around the palladium(II) and platinum(II) ions. The calculated IR and UV-vis spectral data have been correlated to the experimental results. Thermal analysis data support the molecular structures of both complexes. 相似文献
96.
In this article we study two problems raised by a work of Conrey and Ghosh from 1989. Let ζ(k)(s) be the k-th derivative of the Riemann zeta-function, and χ(s) be factor in the functional equation of the Riemann zeta-function. We calculate the average values of ζ(j) and χ at the nontrivial zeros of ζ(k). 相似文献
97.
Saeideh Ebrahimiasl Wan Md. Zin Wan Yunus Anuar Kassim Zulkarnain Zainal 《Solid State Sciences》2010,12(8):1323-1327
Transparent conductive films of tin oxide were deposited on glass substrates under various deposition conditions. Taguchi analysis was used to model the dependence of the grain size, thickness and absorbance of nanocrystalline tin oxide on the process parameters namely pH value, concentration, time of deposition and bath temperature. The effect of the mentioned process parameters on the grain size, thickness and absorbance of deposited layer during the deposition of nanocrystalline was investigated using X-ray diffraction (XRD) technique, atomic force microscopy (AFM) and UV–Visible spectroscopy. Comparison between the model predictions and the experimental observations predicted a remarkable agreement between them. The predictions of the model and sensitivity analysis showed that among the effective process parameters, deposition time and concentration were the main parameters having significant effect on crystalline size. Bath temperature had the most significant effect on absorbance and deposition time had a dominant effect on thickness. 相似文献
98.
Newly synthesized Cu(II) pyrazino[2,3‐f][1,10]phenanthroline complexes as potential anticancer candidates 下载免费PDF全文
New binary and ternary copper(II) complexes, [Cu(py‐phen)2(NO3)]NO3 ( 1 ), [Cu2(py‐phen)2(gly)2(NO3)2(H2O)2]?3H2O ( 2 ) and [Cu2(py‐phen)2(tyr)2(H2O)2](NO3)2?3H2O ( 3 ) (py‐phen: pyrazino[2,3‐f][1,10]phenanthroline; gly: glycine; tyr: tyrosine), have been synthesized and characterized using CHN analysis, electrospray ionization mass spectrometry, Fourier transform infrared spectroscopy and single‐crystal X‐ray diffraction. Interaction of these complexes with calf thymus DNA has been investigated using absorption spectral titration, ethidium bromide and Hoechst 33258 displacement assay and thermal denaturation measurements. These complexes were found to be efficient cleaving agents and cleavage reactions were mediated by hydrolytic and oxidative pathways. The interaction between these complexes and bovine serum albumin (BSA) was investigated using electronic absorption and fluorescence spectroscopy. The experimental results show that the fluorescence quenching mechanism of these complexes and BSA is a static quenching process. Furthermore, in vitro cytotoxicities of these complexes against tumour cell lines (Caco‐2, MCF‐7 and A549) and healthy cell line (BEAS‐2B) showed that they exhibited anticancer activity with low IC50 values. These complexes were markedly active against the cell lines and can be good drug candidates that are effective and safe for healthy tissue. 相似文献
99.
We relate the regularity of the Bergman projection operator and the canonical solution operator to the Nebenhülle of complete Hartogs domains. 相似文献
100.
Yunus Bekdemir Bilge Eren Halil Kütük 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):689-696
Abstract The acid catalyzed hydrolyses of some cyclic disulfonimides, N-(4-substitutedphenyl)-o-benzenedisulfonimides (1a–d) have been studied in concentrated aqueous acidic solutions. Analysis of the data by the Excess Acidity Method, activation parameters, substituent, and solvent deuterium isotope effect are all indicate hydrolysis by an A-1 mechanism in the studied range. 相似文献