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921.
Mohammad Mahdavi Mehdi Asadi Mahsa Khoshbakht Mina Saeedi Mohammad Bayat Alireza Foroumadi Abbas Shafiee 《Helvetica chimica acta》2016,99(5):378-383
A series of novel quinazolin‐4(3H)‐one derivatives were efficiently synthesized starting from isatoic anhydride. First, reaction of isatoic anhydride and amines in H2O at room temperature afforded 2‐aminobenzamides. Then, CuBr/Et3N promoted reaction of 2‐aminobenzamides and different aryl isothiocyanates in DMF at 80° afforded the title compounds in good yield. 相似文献
922.
Ali Ramazani Mehdi Khoobi Fariba Sadri Roghayeh Tarasi Abbas Shafiee Hamideh Aghahosseini Sang Woo Joo 《应用有机金属化学》2018,32(1)
Palladium immobilized magnetic nanoFe3O4@hyperbranched polyethylenimine (Fe3O4@HPEI.Pd) was prepared according to a simple and cost effective pathway and it was employed as a new efficient and selective organic–inorganic hybrid nanocatalyst for the aqueous oxidation of primary and secondary alcohols to their corresponding products in good yields applying oxone (potassium hydrogen monopersulfate) and H2O2 as an oxidant at room temperature. Moreover, the catalytic system was reused at least 13 times without significant loss of activity. The complete characterization of this efficient nanocatalyst was investigated by FTIR, UV–Vis, TEM, SEM, XRD, TGA, VSM, ICP and EDX techniques. 相似文献
923.
Safaei Mohammad Reza Tlili Iskander Gholamalizadeh Ehsan Abbas Tehseen Alkanhal Tawfeeq Abdullah Goodarzi Marjan Dahari Mahidzal 《Journal of Thermal Analysis and Calorimetry》2021,143(3):2453-2462
Journal of Thermal Analysis and Calorimetry - The main aim of the present research is to measure the nucleate boiling heat transfer coefficient (BHTC) of aqueous glycol nano-suspension as a coolant... 相似文献
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Accurate grading of brain gliomas by soft independent modeling of class analogy based on non‐negative matrix factorization of proton magnetic resonance spectra
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K. Ghasemi M. Khanmohammadi H. Saligheh Rad 《Magnetic resonance in chemistry : MRC》2016,54(2):119-125
Hydrogen magnetic resonance spectroscopy (1H‐MRS) is a non‐invasive technique which provides a ‘frequency‐signal intensity’ spectrum of biochemical compounds of tissues in the body. Although this method is currently used in human brain studies, accurate classification of in‐vivo 1H‐MRS is a challenging task in the diagnosis of brain tumors. Problems such as overlapping metabolite peaks, incomplete information on background component and low signal‐to‐noise ratio disturb classification results of this spectroscopic method. This study presents an alternative approach to the soft independent modeling of class analogy (SIMCA) technique, using non‐negative matrix factorization (NMF) for dimensionality reduction. In the adopted strategy, the performance of SIMCA was improved by application of a robust algorithm for classification in the presence of noisy measurements. Total of 219 spectra from two databases were taken by water‐suppressed short echo‐time 1H‐MRS, acquired from different subjects with different stages of glial brain tumors (Grade II (26 cases), grade III (24 cases), grade IV (41 cases), as well as 25 healthy cases). The SIMCA was performed using two approaches: (i) principal component analysis (PCA) and (ii) non‐negative matrix factorization (NMF), as a modified approach. Square prediction error was considered to assess the class membership of the external validation set. Finally, several figures of merit such as the correct classification rate (CCR), sensitivity and specificity were calculated. Results of SIMCA based on NMF showed significant improvement in percentage of correctly classified samples, 91.4% versus 83.5% for PCA‐based model in an independent test set. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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NH4Fe(SO4)2 was found to be a mild and effective catalyst for the selective synthesis of 2‐aryl‐1‐arylmethyl‐1H‐1,3‐benzimidazoles under solvent‐free conditions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Abbas G. Hassan A. Irfan A. Mir M. Mariya-al-Rashida Wu G. 《Journal of Structural Chemistry》2015,56(1):92-101
Journal of Structural Chemistry - A novel mononuclear copper complex [Cu(NH2mpdH)(NH2mpd)2Cl] (1) is synthesized from 2-amino-2-methyl-1,3-propandiol (ampdH4). The crystal structure of (1) is... 相似文献