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排序方式: 共有209条查询结果,搜索用时 46 毫秒
41.
Roya Azad Abolfazl Bezaatpour Mandana Amiri Habibollah Eskandari Sima Nouhi Dereje H. Taffa Michael Wark Rabah Boukherroub Sabine Szunerits 《应用有机金属化学》2019,33(9)
A novel heterogeneous composite material based on reduced graphene oxide (rGO) and bismuth vanadate (BiVO4) was prepared and characterized by various techniques such as powder XRD, HRTEM, EADX, UV–Vis‐DRS, FT‐IR, Raman, BET and XPS analyses. The characterization results reveal that the rGO well decorated by BiVO4. The electrochemical impedance spectroscopy (EIS) shows the increasing of charge transfer of rGO/BiVO4 in presence of light irradiation. In this research, the pure BiVO4 and rGO/BiVO4 composite have been explored for photocatalytic reduction of nitroarenes. Among the prepared nanocomposites, rGO loaded with 10% BiVO4 catalyst (noted as rGO/BiVO4–10%) shows the best performance for the photo‐reduction of various nitroaromatic molecules to their corresponding amine compounds under visible‐light irradiation at room temperature. The catalyst exhibited in particular excellent photocatalytic activity for the conversion of 1,4‐dinitrobenzene to 4‐nitroanilline (100% conversion) in 20 min, 4‐chloronitrobenzene to 4‐chloroaniline and 2‐nitrophenol to 2‐aminophenol (100% conversion) in only 30 min. In addition, the conversion of 4‐bromonitrobenzene, 4‐iodonitrobenzene to their corresponding amine compounds (100% conversion) was achieved in 60 min. The catalyst was recovered for several times and reused without decreasing of its efficiency. 相似文献
42.
Fe3O4@vitamin B1 was designed and prepared as an inexpensive and efficient heterogeneous nanocatalyst for the synthesis of new 1,3‐thiazol derivatives. The structure of the nanomagnetic catalyst was comprehensively characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, energy‐dispersive X‐ray spectroscopy, vibrating sample magnetometry and thermogravimetric analysis. The three‐component, one‐pot condensation of arylglyoxal monohydrate, cyclic 1,3‐dicarbonyls and thioamides in water as a green solvent was applied for the preparation of 1,3‐thiazol derivatives. Simple preparation of the catalyst from commercially available materials, high catalytic activity, simple operation, short reaction times, high yields and use of green solvent are some advantages of this protocol. The superparamagnetic nanocatalyst is magnetically separable and retains its stability after recycling for at least five consecutive runs without detectable activity loss. 相似文献
43.
<正>An efficient and mild method for the direct conversion of alcohols into N-alkylphthalimides using 2,4,6-trichloro-1,3,5-triazine and dimethylformamide was described.The reaction was preceded via(alcoxymethylene) dimethylammonium chloride intermediate and produced corresponding N-alkylphthalimides in good-to-excellent yields. 相似文献
44.
Kavkhani Roya Pourzaki Mahtab Kianvash Abbas Hajalilou Abdollah Adli Reza Ghaffari 《Journal of Sol-Gel Science and Technology》2021,99(2):444-454
Journal of Sol-Gel Science and Technology - In this study, Mg–Mn–Al ferrite with a chemical composition of Mg0.8Mn0.2Al0.1Fe1.9O4 was synthesized via the sol–gel auto-combustion... 相似文献
45.
Morteza Shiri Mohammad Ali Zolfigol Mahtab Pirveysian Roya Ayazi-Nasrabadi Hendrik G. Kruger Tricia Naicker Iraj Mohammadpoor-Baltork 《Tetrahedron》2012,68(30):6059-6064
Preparation of 2-(indol-3-yl)-3-nitriloquinolines via Friedländer quinoline synthesis using 3-cyanoacetylindoles possessing an α-methylene group and ortho-amino arylketones have been described. This reaction took place in PEG-400 as a green solvent and it is catalyzed with polyphosphoric acid (PPA) to give novel types of quinolines containing both indoles and cyano functions in one step under thermal and microwave conditions. 相似文献
46.
Roya Mohammadzadeh Kakhki 《Russian Journal of Applied Chemistry》2017,90(7):1030-1039
It is shown that the sensor arrays can acquire more information on a given sample than an individual sensor. The main classes of gas-sensing materials include metal-oxide semiconductors. Gas sensors based on chemiresistive semiconducting metal-oxides have many potential benefits including, their very low cost, fast response, recovery time, simple electronic interface, ease of use, and ability to detect a large analytes. Recent advances in gas sensor arrays have shown the capability to incorporate nanomaterial based cross-reactive array. In this way it is possible to increase the surface/volume ratio of the sensing layer. Therefore the surface scattering is better influenced by adsorbed species and change in sensor conductivity is higher. Also the sensitivity of semiconductor oxide materials can be improved by using of nanoparticles. Gas sensor arrays based on nanotechnology can rapidly, sensitively, and selectively detect target molecules. 相似文献
47.
48.
Scott R. Broderick Changwon Suh J Provine Christopher S. Roper Roya Maboudian Roger T. Howe Krishna Rajan 《Surface and interface analysis : SIA》2012,44(3):365-371
We have demonstrated an informatics methodology for finding correlations between the full profile Fourier transform infrared spectra of polycrystalline 3C‐silicon carbide (poly‐SiC) films and their growth conditions, thereby developing high‐throughput structure‐process relationships. Because SiC films are a structural element in photonic sensors, this paper focuses on the interpretation of their optical response, the multivariate tracking of critical processing pathways, and the identification of controlling processing mechanisms. Using principal component analysis, we have developed a data analysis tool to aid in the assessment of the relative contributions of experimental parameters in low‐pressure chemical vapor deposition processes to optical responses on the basis of the size of eigenvalues of the spectral data set. The applied methodology for identifying spectral relationships of stoichiometry, dopant chemistry, and microstructure of poly‐SiC provides more effective guidelines to manipulate optical responses by controlling multiple experimental parameters. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
49.
A one-pot procedure has been developed for the synthesis of β-phosphonomalonates via P-C bond formation through tandem Knoevenagel–phospha–Michael reaction catalyzed by iodine as a new, inexpensive, nonmetallic, and commercially available catalyst. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
50.
Seyyed Javad Sabounchei Mohsen Ahmadi Zahra Nasri Esmaeil Shams Sadegh Salehzadeh Yasin Gholiee Roya Karamian Mostafa Asadbegy Sepideh Samiee 《Comptes Rendus Chimie》2013,16(2):159-175
The non-symmetric phosphorus ylides and their Pd(II) complexes have been synthesized as potential antioxidant and antibacterial compounds and their structures were elucidated using a variety of physicochemical techniques. The reaction of 1 equiv non-symmetric phosphorus ylides, Ph2PCH2PPh2C(H)C(O)PhX (X = Br (Y1), Cl (Y2), NO2 (Y3), OCH3 (Y4)) with [Pd(dppe)Cl2] (M1), followed by treatment with 2 equiv AgOTf led to monomeric chelate complexes, [(dppe)Pd(Ph2PCH2PPh2C(H)C(O)PhX)] (OSO2CF3)2 (X = Br (C1), Cl (C2), NO2 (C3), OCH3 (C4)), which contain a five-membered P,P chelate ring in one side and a five-membered P,C chelate ring in the other side. Palladium ion complexes were synthesized and investigated by cyclic voltammetry, FT-IR, UV–visible, multinuclear (1H, 31P and 19F) NMR, thermal analysis and ESI-mass spectroscopic studies. Some complexes and ligands have been studied by powder XRD and single crystal X-ray diffraction techniques. FT-IR and 31P NMR studies revealed that the ylides Y are coordinated to the metal ions via the terminal phosphorus (Pc) of the ylides and methene group (CH). The proposed coordination geometry around the Pd atom in these complexes is defined as slightly distorted square planar by UV-Visible and DFT studies. Thermal stability of all complexes was also shown by TG/DTG methods. Furthermore, the electrochemical behavior of the complexes was investigated by cyclic voltammetry. The results indicate that all complexes are successfully synthesized from the initial ligands. All complexes were analyzed for their antioxidant properties by DPPH free radical scavenging assay. In addition, the antibacterial effects of the hexane-solved complexes were investigated by disc diffusion method against four Gram positive and negative bacteria. All complexes represented antibacterial activity against bacteria tested especially on Gram positive ones. A theoretical study on the structure, 1H and 31P NMR chemical shifts and the interaction energy between the Pd2+ ion and ligands dppe and ylide Y is also reported. 相似文献