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排序方式: 共有141条查询结果,搜索用时 15 毫秒
1.
We report an ecofriendly synthetic approach for the fabrication of biogenic gold nanoparticles (AuNPs) using electron-rich sea cucumber extract as a bio-reductant and stabilizing agent in reducing gold cations into AuNPs at the optimal conditions. The produced AuNPs are spherical in shape with an average particle size of 11 ± 1.5 nm in transmission electron microscopy (TEM) and exhibited a crystal structure of face-centered cubic in X-ray diffraction (XRD) analyses. Our results indicated that bioinspired AuNPs demonstrate superior catalytic activity in the safe and facile one-pot synthesis of polyhydroquinoline derivatives under solvent-free reaction conditions. This green route encompasses multiple benefits including highly recyclable bioinspired catalyst (5 cycles), short reaction times, convenient workout, high to excellent product yields (82%–97%), and nonhazardous conditions. 相似文献
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Molecular Diversity - In this research, QSAR modeling was carried out through SMILES of compounds and on the basis of the Monte Carlo method to predict the antioxidant activity of 79 derivatives of... 相似文献
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Sayahi Mohammad Hosein Saghanezhad Seyyed Jafar Mahdavi Mohammad 《Research on Chemical Intermediates》2018,44(1):739-747
Research on Chemical Intermediates - A novel four-component approach for the synthesis of 1-phenyl-1,4-dihydro-2H-9-oxa-4-aza-phenanthrene-3,10-dione derivatives has been presented via the reaction... 相似文献
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Reza Abbasi Jafar Mostafavi Amjad Hamed Nosrati Ramin Mohammadkhani Hosein Danafar 《应用有机金属化学》2020,34(10):e5825
Nowadays, nanostructures have been given significant attention in medical and biological fields. Among these nanostructures, graphene oxide (GO) has been widely used in drug delivery systems, because of its unique properties, and the ability to connect to other nanostructures such as magnetic nanoparticles (NPs) as well as polymers by its functional groups. In this research, first, GO was prepared by exfoliating graphite according to the modified Hummer’s method, and then the Fe3O4 NPs were synthesized by a simple co-precipitation method on GO nanosheets. In the next step, with the help of the ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-hydroxysuccinimide coupling reagents, the polyethylene glycol (PEG) polymer was bonded to the GO-Fe3O4 nanocomposite. Finally, anti-cancer drug, curcumin (Cur) was loaded onto the nanocomposite and the Cur loading ratio was measured at about 8%. The samples were evaluated using Fourier transform-infrared, differential scanning calorimtery, vibrating-sample magnetometry, atomic force microscopy and dynamic light scattering techniques. The results show that the prepared nanocomposite is an appropriate candidate for biomedical applications. 相似文献
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Ezoji Hosein Shafaghat Rouzbeh Jahanian Omid 《Journal of Thermal Analysis and Calorimetry》2019,135(3):1775-1785
Journal of Thermal Analysis and Calorimetry - Homogeneous charge compression ignition (HCCI) combustion phasing control is one of the most difficult challenges of operating this new concept of... 相似文献
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In this paper, we present a new optimized symmetric ten-step predictor–corrector method with phase-lag of order infinity (phase-fitted). The method is based on the symmetric eight-step predictor–corrector method of Simos and et al, that is constructed to solve numerically the radial Schrödinger equation during the resonance problem with the use of the Woods–Saxon potential. It can also be used to integrate related IVPs with oscillating solutions such as orbital problems. We compare the new method to some recently constructed optimized methods from the literature. We measure the efficiency of the methods and conclude that the new method with infinite order of phase-lag is the most efficient of all the compared methods and for all the problems solved. 相似文献
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Engineering a Cu‐MOF Nano‐Catalyst by using Post‐Synthetic Modification for the Preparation of 5‐Substituted 1H‐Tetrazoles 下载免费PDF全文
A new nano scale Cu‐MOF has been obtained via post‐synthetic metalation by immersing a Zn‐MOF as a template in DMF solutions of copper(II) salts. The Cu‐MOF serves as recyclable nano‐catalyst for the preparation of 5‐substituted 1H‐tetrazoles via [3 + 2] cycloaddition reaction of various nitriles and sodium azide in a green medium (PEG). The post‐synthetic metalated MOF were characterized by FT‐IR spectroscopy, powder X‐ray diffraction (PXRD), atomic absorption spectroscopy (AAS), and energy dispersive X‐ray spectroscopy (EDX) techniques. The morphology and size of the nano‐catalyst were determined by field emission scanning electron microscopy (FE‐SEM). 相似文献
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