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Nanosheet of PdNiZn and nanosphere of PdNiZn/reduced‐graphene oxide (RGO) with sub‐3 nm spheres have been successfully synthesized through a facile oil‐water interfacial strategy. The morphology and composition of the films were determined by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive analysis of X‐ray (EDAX) and elemental mapping. In the present study, we have developed a method to minimize the usage of precious Pd element. Due to the special structure and intermetallic synergies, the PdNiZn and PdNiZn/RGO nanoalloys exhibited enhanced catalytic activity and durability relative to Pd nanoparticles in Suzuki‐Miyaura C‐C cross‐coupling reaction. Compared to classical cross‐coupling reactions, this method has the advantages of a green solvent, short reaction times, low catalyst loading, high yields and reusability of the catalysts. 相似文献
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Lal Sohan Arora Sanjiv Kumar Vinod Rani Shikha Sharma Chetan Kumar Parvin 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1707-1716
Journal of Thermal Analysis and Calorimetry - The synthesis of Schiff bases of chitosan is performed by the reaction of chitosan with different heteroaryl aldehydes, i.e., furfuraldehyde,... 相似文献
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Parvin Sarabadani Mahdi Sadeghi Mohamadreza Ghasemi Zargham Asadollahi Narges Afshari 《Journal of Cluster Science》2011,22(2):131-140
High purity tin oxide nanopowders have been synthesized by using a solid-state chemical reaction technique with annealing
at elevated temperature. The effects of two parameters, specifically by controlling the annealing temperature and kind of
alkaline chlorides as precursors, the effect on particle size, morphology and IR spectra of synthesized tin oxide nanopowder
were investigated. From the X-ray pattern, the crystal structure of the synthesized powders was confirmed as a tetragonal
structure. Based on the recorded FTIR spectrum of SnO2, the IR bands due to SnO2 vibrations and its lattice modes were observed at 625 and 690 cm−1, respectively. In addition, an important characterization peak has been identified at 1,450 cm−1 due to Sn–O–Sn bridges observed only when LiCl was used as precursor. The formation of Sn–O–Sn bridges was confirmed by TGA–DTA
analysis. According to the SEM images, it is obvious to notice that the kind of alkaline chlorides as precursors play a dominant
role in controlling the morphology of tin oxide nanopowders. 相似文献
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Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork Saeedeh Gorjipoor Parvin Yazdani 《合成通讯》2013,43(3):552-561
Efficient ring opening of epoxides with aromatic amines catalyzed by ZrO(OTf)2 is reported, and the corresponding β amino (beta-amino acid) alcohols were obtained in high yields in CH3CN as solvent. The reactions were carried out at room temperature and in the presence of only 1.25 mol% of ZrO(OTf)2. This catalyst can be reused several times without loss of its activity. 相似文献
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One‐pot Synthesis of Highly Functionalized Tetrahydropyridines: A Camphoresulfonic Acid Catalyzed Multicomponent Reaction 下载免费PDF全文
A simple and straight forward solvent free method for the synthesis of a series of highly functionalized tetrahydropyridine derivatives has been achieved via multicomponent reaction of aromatic aldehydes, various amines, and β‐keto esters at room temperature using readily available (±)‐camphor‐10‐sulfonic acid as an organocatalyst. The current protocol offers an atom economic and environmentally benign method for the synthesis of the title compounds under solvent free conditions in good yields with high substrate scope and avoids column chromatographic purification. 相似文献
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A diacid (TOBA) containing an ester group was synthesized by reaction of terephthaloyl chloride with 4-hydroxybenzoic acid. Reaction of the obtained diacid with thionyl chloride resulted in preparation of the related diacid chloride (TOBC). Nucleophilic substitution reaction of 4-aminophenol and also 5-amino-l-naphthol with the prepared diacid chloride afforded two aromatic diols containing ester and amide groups, respectively. Aromatic and semi-aromatic poly(ester-amide-urethane)s were prepared via addition polymerization of different diisocyanates with novel diols. The prepared polyurethanes showed improved thermal stability. 相似文献
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Tapas Kumar Mandal Nargish Parvin Sang W. Joo 《Particle & Particle Systems Characterization》2021,38(11):2100110
This study reports a fluorescence iron core-carbonized biocompatible hybrid poly(ethylene glycol) (PEG)-oriented nanogel (Fe2O3@C@PEG-COOH nanogel). The fluorescence Fe2O3@C@PEG-COOH nanogel is prepared using a facile one-pot polycondensation reaction without organic solvents or catalysts. The properties of the fluorescenceFe2O3@C@PEG-COOH nanogel are investigated by fluorescence spectroscopy, transmission electron microscopy, X-ray diffraction, and thermogravimetric analysis. A change in pH as a stimulus can trigger the release of loaded doxorubicin (DOX). Under acidic conditions, the nanogel releases the highly loaded drug slowly compared to the neutral and basic conditions, which is important for cancer treatment. The synthesized fluorescenceFe2O3@C@PEG-COOH nanogel is well dispersed in water and shows fluorescence with high photostability, good biocompatibility with a paramagnetic nature. Furthermore, the nanogel can act as a potential fluorescent probe for cell imaging. 相似文献
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An expeditious and effective method for synthesis of isoxazoline from aldoximes and activated alkenes using cetyltrimethylammonium cerium nitrate at room temperature is described. Reaction was completed within short time period in high yields at room temperature. 相似文献