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排序方式: 共有322条查询结果,搜索用时 515 毫秒
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M. Shirazi M.T. HosseinnejadA. Zendehnam Z. GhorannevisM. Ghoranneviss 《Applied Surface Science》2011,257(23):10233-10238
Zinc oxide (ZnO) thin films were deposited on LiNbO3 (LN) single crystals with 200 nm thicknesses by three different ways, where coating of zinc (Zn) film was followed by thermal oxidation for four, two, and one steps with 50, 100, and 200 nm thicknesses repeatedly. Sample, which was produced at 4-step of deposition and oxidation of Zn layer, showed high transmittance and low structural defect due to a lower photoluminescence intensity and Urbach energy. Average grain size in X-ray diffraction (XRD), scanning electron microscopy (SEM) micrograph, and atomic force microscopy (AFM) images for multilayer of ZnO was lower than monolayer of ZnO thin films. Applying multilayer coating technique leads to decrease of surface roughness and scattering on light on surface and fabrication of LiNbO3 waveguides with lower optical loss. 相似文献
94.
Hamed Soleimani Mirmehdi Seyyed-Esfahani Mohsen Akbarpour Shirazi 《Annals of Operations Research》2016,242(2):399-421
Analyzing current trends in supply chain management, lead to find unavoidable steps toward closing the loop of supply chain. In order to expect best performance of Closed-Loop Supply Chain (CLSC) network, an integrated approach in considering design and planning decision levels is necessary. Further, real markets usually contain uncertain parameters such as demands and prices of products. Therefore, the next important step is considering uncertain parameters. 相似文献
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Zeinab Kamali Mahmood Lashkarizadeh Bami 《Journal of Fourier Analysis and Applications》2014,20(2):225-233
The classical Bochner-Schoenberg-Eberlein theorem characterizes the continuous functions on the dual group of a locally compact abelian group G which arise as Fourier-Stieltjes transforms of elements of the measure algebra M(G) of G. This has led to the study of the concept of a BSE-algebra as introduced by Takahasi and Hatori in 1990. In the present paper we establish affirmatively a question raised by Takahasi and Hatori that whether $L^{1}({\mathbb{R}}^{+})$ is a BSE-algebra. 相似文献
97.
Saeed Yousefinejad Fatemeh Honarasa Fatemeh Abbasitabar Zeinab Arianezhad 《Journal of solution chemistry》2013,42(8):1620-1632
Because of the importance of the solubility of buckminsterfullerene, C60, as the most well-known carbon nanomaterial, a multiparameter linear model is proposed for C60 solubility in different solvents using solvent empirical parameters. The obtained model covers more than 81 and 87 % of the variance in the training and test sets, respectively. On the other hand, because of the potential of solvent empirical parameters for probing different aspects of the solvent–solute interactions, some information about the solubility of C60 in solution phase was obtained. The results showed that hydrogen bond donation ability, basicity scale and dispersion interactions were some of the effective parameters for correlating the solubility of C60 in various solvents. 相似文献
98.
Ghodsi Mohammadi Ziarani Alireza Badiei Zeinab Dashtianeh Parisa Gholamzadeh Nina Hosseini Mohtasham 《Research on Chemical Intermediates》2013,39(7):3157-3163
Sulfonic-acid-functionalized silica was applied as an efficient heterogeneous acid catalyst in the Ritter reaction to prepare amides by reaction of various benzylic, allylic, and tertiary alcohols with various nitriles in good to excellent yields under solvent-free conditions. The simplicity of the reaction, recovery of catalyst without loss of reactivity, high yield of products, and short reaction time represent improvements over many existing methods. 相似文献
99.
Zeinab H. Ismail Soad M. Abdel-Gawad Anhar Abdel-Aziem M. M. Ghorab 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1795-1805
A novel series of the pyrazolo[3,4-d]pyrimidines having biologically active sulfur moieties 3-20 were prepared via reaction of 4-mercapto-1-phenyl-1 H -pyrazolo[3,4-d]pyrimidine 3 with different reagents. Identification of the new compounds was established by elemental analyses, IR, 1 H-NMR, and mass spectral data. Some of the obtained compounds showed the interesting antimicrobial activity comparable to antibiotic chloramphenicol as standard antibacterial agent and Terbinafin as a standard antifungal agent. 相似文献
100.
A novel Ni‐catalyzed cross‐coupling reaction is introduced for the direct synthesis of diaryldisulfanes and dialkyldisulfanes from aryl halides and primary alkyl halides at normal atmospheric conditions, respectively. This one‐pot and domino protocol utilizes only 10 mol% of NiCl2 as a catalyst and morpholin‐4‐ium morpholine‐4‐carbo‐dithioate as a new, stable, solid, and odorless sulfurating reagent in the presence of ethylene glycol as a cosolvent and bidentate ligand in dimethyl formamide (DMF) at 130°C with good to excellent yields and relatively short time reaction. 相似文献