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1.
Maryam Mirza-Aghayan Rabah Boukherroub Mahshid Rahimifard 《Journal of organometallic chemistry》2007,692(23):5113-5116
The palladium(II) chloride/triethylsilane system has been successfully applied for the selective hydrogenation of the carbon-carbon double bond of α,β-unsaturated ketones to yield the corresponding saturated carbonyl compounds. The reaction takes place under mild conditions and affords high yields. 相似文献
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Yoichi Makimizu Nhat Truong Nguyen Jiri Tucek Hyo-Jin Ahn JeongEun Yoo Mahshid Poornajar Imgon Hwang Stepan Kment Prof. Dr. Patrik Schmuki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(12):2685-2692
Photoelectrochemical (PEC) water splitting is a promising method for the conversion of solar energy into chemical energy stored in the form of hydrogen. Nanostructured hematite (α-Fe2O3) is one of the most attractive materials for a highly efficient charge carrier generation and collection due to its large specific surface area and the short minority carrier diffusion length. In the present work, the PEC water splitting performance of nanostructured α-Fe2O3 is investigated which was prepared by anodization followed by annealing in a low oxygen ambient (0.03 % O2 in Ar). It was found that low oxygen annealing can activate a significant PEC response of α-Fe2O3 even at a low temperature of 400 °C and provide an excellent PEC performance compared with classic air annealing. The photocurrent of the α-Fe2O3 annealed in the low oxygen at 1.5 V vs. RHE results as 0.5 mA cm−2, being 20 times higher than that of annealing in air. The obtained results show that the α-Fe2O3 annealed in low oxygen contains beneficial defects and promotes the transport of holes; it can be attributed to the improvement of conductivity due to the introduction of suitable oxygen vacancies in the α-Fe2O3. Additionally, we demonstrate the photocurrent of α-Fe2O3 annealed in low oxygen ambient can be further enhanced by Zn-Co LDH, which is a co-catalyst of oxygen evolution reaction. This indicates low oxygen annealing generates a promising method to obtain an excellent PEC water splitting performance from α-Fe2O3 photoanodes. 相似文献
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Regioselective synthesis of novel spiroindane-1,3-diones through 1,3-dipolar cycloaddition reactions
A facile synthesis of novel spiroindane-1,3-diones has been achieved via 1,3-dipolar cycloaddition of an azomethine ylide, generated in situ from ninhydrin and 1,2,3,4-tetrahydroisoquinoline, with the conjugated double bond of chalcone derivatives. The regiochemistry and structures of the cycloadducts were determined with spectroscopic data and by X-ray crystal structure analysis. 相似文献
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This study proposes an expectation–maximization (EM)-based curve evolution algorithm for segmentation of magnetic resonance brain images. In the proposed algorithm, the evolution curve is constrained not only by a shape-based statistical model but also by a hidden variable model from image observation. The hidden variable model herein is defined by the local voxel labeling, which is unknown and estimated by the expected likelihood function derived from the image data and prior anatomical knowledge. In the M-step, the shapes of the structures are estimated jointly by encoding the hidden variable model and the statistical prior model obtained from the training stage. In the E-step, the expected observation likelihood and the prior distribution of the hidden variables are estimated. In experiments, the proposed automatic segmentation algorithm is applied to multiple gray nuclei structures such as caudate, putamens and thalamus of three-dimensional magnetic resonance imaging in volunteers and patients. As for the robustness and accuracy of the segmentation algorithm, the results of the proposed EM-joint shape-based algorithm outperformed those obtained using the statistical shape model-based techniques in the same framework and a current state-of-the-art region competition level set method. 相似文献
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Hossaini Mahshid Heydari Reza Maghsoodlou Malek Taher Graiff Claudia 《Research on Chemical Intermediates》2017,43(7):4189-4199
Research on Chemical Intermediates - A convenient, one-pot, multicomponent synthesis of new (4-oxothiazolidine-2-ylidene)benzamide derivatives by unsymmetrical thioureas, various amines and methyl... 相似文献
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Mahdieh Darroudi Sara Ranjbar Mohammad Esfandiar Mahsima Khoshneviszadeh Mahshid Hamzehloueian Mehdi Khoshneviszadeh Yaghoub Sarrafi 《应用有机金属化学》2020,34(12):e5962
In the present work, novel 5-((1-benzyl-1,2,3-triazol-4-yl)methoxybenzylidene)-2-(arylamino)thiazol-4-one thiazolone incorporated triazole derivatives have been designed as tyrosinase inhibitors. The compounds were synthesized through click reaction in good yield. Moreover, the antityrosinas activity of the synthesized derivatives was evaluated. In the search for establishing a click copper-catalyzed azide/alkyne cycloaddition (CuAAC) reaction under strict conditions, in terms of a novel air-stable, a recyclable and efficient magnetic catalyst was planned for new triazole derivatives as a well-organized copper iodide supported on the functionalized Fe3O4@SiO2 core-shell (CuI/Fe3O4@SiO2(TMS-EDTA) nanoparticles). The engineered nanocatalyst synthesized for the first time and characterized by different methods, including FT-IR spectroscopy, XRD, FESEM, EDX, TEM, TGA, and BET analysis. The excellent catalytic performance in ethanol with high surface area (351.7 m2g−1) and short reaction time for diverse functional groups (120–200 min), no use of toxic solvents, reusability of the catalyst, and using eco-friendly conditions are the advantageous of this work. Moreover,the nanocatalyst can be used at least five times without any significant decrease in the yield of the reaction. The thiazolidine-triazole derivatives 9a , 9c , 9e , and 9 g showed promising tyrosinase inhibitory activity with IC50 values in the range of 5.90–9.81 μM. The compounds were found to be considerably more potent tyrosinase inhibitors than the reference inhibitor kojic acid (IC50 = 18.36 μM). 相似文献
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Structural Chemistry - The molecular mechanism of the cycloaddition reactions of 2H-azirine with 1-methoxybutadiene and cyclohexadiene has been studied at the M06-2X/cc-pVDZ level of theory.... 相似文献
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Palladium on activated carbon catalyzed reductive amination of aldehydes and ketones by triethylsilane 下载免费PDF全文
Maryam Mirza‐Aghayan Mahdieh Molaee Tavana Mahshid Rahimifard Rabah Boukherroub 《应用有机金属化学》2014,28(2):113-115
Various aldehydes and ketones were efficiently transformed into the corresponding amines using amine derivatives in the presence of triethylsilane and a catalytic amount of palladium on activated carbon in ethanol. The proposed method provides a one‐pot synthesis of various amines in excellent yields after short reaction times. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献