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141.
Thermal Characteristics of PVA-PANI-ZnS Nanocomposite Film Synthesized by Gamma Irradiation Method 下载免费PDF全文
Gamma irradiation is employed for in situ preparation of PVA-PANI-ZnS nanocomposite. The irradiation dose is varied from 10 to 40 kGy at 10 kGy intervals. The XRD result confirms the formation of crystalline phases corresponding to ZnS nanoparticles, PVA and PANI. Field emission scanning electron microscopy shows the formation of agglomerated PANI along the PVA backbone, within which the ZnS nanoparticles are dispersed.UV-visible spectroscopy is conducted to measure the transmittance spectra of samples revealing the electronic absorption characteristics of ZnS and PANI nanoparticles. Photo-acoustic(PA) setup is installed to investigate the thermal properties of samples. The PA spectroscopy indicates a high value of thermal diffusivity for samples due to the presence of ZnS and PANI nanoparticles. Moreover, at higher doses, the more polymerization and formation of PANI and ZnS nanoparticles result in enhancement of thermal diffusivity. 相似文献
142.
Microchimica Acta - Gold nanoparticles (AuNP) were deposited on the surface of multiwalled carbon nanotubes (MWCNT) by in-situ thermal decomposition of gold acetate under solvent and reducing agent... 相似文献
143.
Zeynizadeh Behzad Mousavi Hossein Sepehraddin Farhad 《Research on Chemical Intermediates》2020,46(7):3361-3382
Research on Chemical Intermediates - In this paper, a new application of the Fe3O4@APTMS@Cp2ZrClx(x = 0, 1, 2) MNPs as a robust and highly efficient Pd-free catalytic system in the environmentally... 相似文献
144.
Zeynizadeh Behzad Sadeghbari Maryam Noroozi Pesyan Nader 《Journal of the Iranian Chemical Society》2020,17(1):73-88
Journal of the Iranian Chemical Society - In this study, we have synthesized magnetically nanoparticles (MNPs) of CuFe2O4@SiO2@AAPTMS@Ni(II) and CuFe2O4@SiO2@AAPTMS@Cu(II). The prepared... 相似文献
145.
Zahra Afzali Mohammad Reza Vaezi Behzad Aghabarari Maria Victoria Martinez Huerta 《中国化学会会志》2020,67(2):267-276
In this study, Y zeolite nanocrystals were synthesized without an organic template and were used as a support for bifunctional nanocatalysts in the hydroisomerization of n-octane. Different types of catalysts were synthesized by loading Pt, Cr, and phosphomolybdic acid (HPMo) on Y zeolite nanocrystal supports and were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), field emission scanning electron microscope (FE-SEM), and transmission electron microscope (TEM) analysis. The Cr-Pt/HPMo-Y nanocatalyst with a surface area of approx. 600 m2/g showed the best performance in the hydroisomerization of n-octane. The optimization of n-octane hydroisomerization over bifunctional nanocatalysts supported on nanocrystalline Y zeolite, in the presence of H2 gas, was applied based on the response surface methodology (RSM) and Box–Behnken design (BBD) template. The effect of three different process variables on the yield of iso-alkanes as the purpose process was determined. Experiments were carried out using a fixed-bed microreactor under different ranges of weight hourly space velocity (WHSV) (A = 0.5–1.5 hr−1), H2 to n-C8 molar ratio (B = 1:1–3:1), and reaction temperature (C = 200–300°C). The RSM proved that the temperature variable had the greatest impact on the hydroisomerization reaction yield. 相似文献
146.
In graph theory, the related problems of deciding when a set of vertices or a set of edges constitutes a maximum matching or a minimum covering have been extensively studied. In this paper we generalize these ideas by defining total matchings and total coverings, and show that these sets, whose elements in general consist of both vertices and edges, provide a way to unify these concepts. Parameters denoting the maximum and the minimum cardinality of these sets are introduced and upper and lower bounds depending only on the order of the graph are obtained for the number of elements in arbitrary total matchings and total coverings. Precise values of all the parameters are found for several general classes of graphs, and these are used to establish the sharpness of most of the bounds. In addition, variations of some well known equalities due to Gallai relating covering and matching numbers are obtained. 相似文献
147.
148.
Bahram Bahramian Mohammad Bakherad Ali Keivanloo Zohre Bakherad Behzad Karrabi 《应用有机金属化学》2011,25(6):420-423
We report here our observation that, using appropriate reaction conditions, the Sonogashira reaction can be performed without the need for copper catalyst and solvent. Our approach involves the use of diatomite‐supported palladium(II) salophen complex as a catalyst and triethylamine as a base. The methodology works, to differing extents, for aryl iodides and bromides. This heterogeneous catalyst can be reused at least five times without any decrease in activity. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
149.
Behzad Maheri Kalejahi Morteza Bahram Abdolhossein Naseri Siyavash Bahari Masomeh Hasani 《Journal of the Iranian Chemical Society》2014,11(1):241-248
In this work, multivariate curve resolution-alternating least squares (MCR-ALS) has been applied to resolve and study the simultaneous degradation of three toxic organic dyes using Fenton reaction. Second-order kinetic-spectrophotometric data in the simultaneous degradation of malachite green, crystal violet and methylene blue were analyzed by MCR analysis to get their concentration profiles and calculate their degradation factors. The effect of three parameters (Fe2+, H2O2 concentration and initial pH) and their possible interaction in the simultaneous degradation of mentioned dyes were studied and optimized using experimental design and response surface method. Acquiring second-order data makes possible the analysis and study of the studied dyes in the gray systems which is termed as second-order advantage in the literatures. The prominent point of this work is the combination of second-order data and response surface methodology. 相似文献
150.
In this study, the immobilization of sulfonic acid on silica‐layered magnetite was carried out by the reaction of ClSO3H with silica‐layered magnetite. The prepared magnetic nanoparticles of Fe3O4@SiO2‐SO3H were then characterized using scanning electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, vibrating sample magnetometry, and transmission electron microscopy. The sulfonated nanocomposite exhibited excellent catalytic activity and reusability in the reduction of various aldoximes and ketoximes with NaBH3CN in the presence of ZrCl4. All reactions were carried out under solvent‐free conditions (r.t. or 75–80°C) within 3–70 min to afford amines in high to excellent yields. 相似文献