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931.
Rahim Hekmatshoar Sodeh Sajadi Samaheh Sadjadi Majid M. Heravi Yahya S. Beheshtiha Fatemeh F. Bamoharram 《中国化学会会志》2008,55(6):1195-1198
12‐Molybdophosphoric acid catalyzed transfer hydrogenation of nitroarene by hydrazine in a homogeneous phase. This catalytic system was applicable to one‐pot quinolines synthesis in the presence of various aldehydes in water. This method provides a new and efficient protocol in terms of mild reaction conditions, clean reaction profiles, small quantity of catalyst, and simple work‐up procedure. 相似文献
932.
o‐Phenylenediamine derivatives readily react with benzoyl chloride derivatives in the presence of MCM‐41 as catalyst to yield 2‐substituted benzimidazoles in very good yields. 相似文献
933.
Abdouss Majid Shokri Aref Karimi Mohammad Mehdi Zargaran Mojdeh 《Russian Journal of Applied Chemistry》2022,95(3):366-378
Russian Journal of Applied Chemistry - In this project, the fibers were applied to increase the tensile strength of the concrete and produce fiber reinforced concrete (FRC). Polypropylene (PP) is... 相似文献
934.
Maryam Zakeri Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Iraj Mohammadpoor‐Baltork Zari Pahlevanneshan 《应用有机金属化学》2018,32(1)
In this paper, the design and characterization of a new heterogeneous catalyst by incorporation of copper ions into the nanosilica modified by thiole–based dendrimer are reported. The prepared catalyst was characterized by FT–IR, TGA, elemental analysis, FE–SEM, TEM, XPS and ICP–OES techniques. This material was used as catalyst in the synthesis benzimidazoles and benzothiazoles by the reaction of substituted benzaldehydes with 1,2–diaminobenzene or 2–aminothiophenol, respectively. The advantages of the present catalytic system are high yields, mild conditions and short reaction times. On the other hand, this new synthesized catalyst was recycled very well and reused several times without significant loss of its catalytic activity. 相似文献
935.
Oxido‐peroxido W(VI)‐histidine–MgAl‐layered double hydroxide composite as an efficient catalyst in sulfide oxidation 下载免费PDF全文
Mohammad Nikkhoo Mojtaba Amini S. Morteza F. Farnia Arshad Bayrami Mojtaba Bagherzadeh Sanjeev Gautam Keun Hwa Chae 《应用有机金属化学》2018,32(6)
Oxido‐peroxido W(VI)‐histidine–MgAl‐layered double hydroxide composite was prepared by using MgAl‐layered double hydroxide as a host and oxido‐peroxido W(VI)‐histidine complex as a guest. The composite was characterized by XRD, IR, EDX,SEM and TEM techniques. This composite is tested for catalytic selective sulfoxidation reactions using hydrogen peroxide as oxidant showing good to moderate conversion along with high selectivity. 相似文献
936.
Nano–silica functionalized with thiol–based dendrimer as a host for gold nanoparticles: An efficient and reusable catalyst for chemoselective oxidation of alcohols 下载免费PDF全文
Sara Haghshenas Kashani Amir Landarani‐Isfahani Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor‐Baltork 《应用有机金属化学》2018,32(9)
In this paper, we present the synthesis of Au nanoparticles supported on nanosilica thiol based dendrimer, nSTDP. The catalyst was prepared by reduction of HAuCl4 with NaBH4 in the presence of nSTDP. The resulting Aunp–nSTDP materials were characterized by FT–IR and UV–vis spectroscopic methods, SEM, TEM, TGA, XPS and ICP analyses. The characterization of the catalyst showed that Au nanoparticles with the size of 2–6 nm are homogeneously distributed on the nSTDP dendrimer with a catalyst loading of about 0.19 mmol/g of catalyst. The Aunp–nSTDP catalyst was used in the oxidation of alcohols with tert–butyl hydroperoxide (TBHP) as oxidant. The influence of vital reaction parameters such as solvent, oxidant and amount of catalyst on the oxidation of alcohols was investigated. These reactions were best performed in an acetonitrile/water mixture (3:2) in the presence of 0.76 mol% of the catalyst on the basis of the Au content at 80 °C under atmospheric pressure of air to afford the desired products in high yields (80–93% for benzyl alcohols). The Aunp–nSTDP catalyst exhibited a high selectivity toward the corresponding aldehyde and ketone (up to 100%). Reusabiliy and stability tests demonstrated that the Aunp–nSTDP catalyst can be recycled with a negligible loss of its activity. Also this catalytic exhibited a good chemoselectivity in the oxidation of alcohols. 相似文献
937.
Taghavizadeh Yazdi Mohammad Ehsan Khara Jalil Sadeghnia Hamid Reza Esmaeilzadeh Bahabadi Sedigheh Darroudi Majid 《Research on Chemical Intermediates》2018,44(2):1325-1334
Research on Chemical Intermediates - Silver nanoparticles (Ag-NPs) were synthesized through a facile and “green” method, which uses the aqueous shoots extract of Rheum turkestanicum at... 相似文献
938.
The analysis of water distribution network is of great interest to hydraulic engineers. Although the water distribution network has been extensively studied for the last decades, there are still many unsolved problems awaiting clarification. In this paper, an algorithm is presented that describes a computationally efficient technique for water distribution networks based on Gröbner basis method. Gröbner basis algorithm provides the exact algorithmic solutions for solving the system of equations. However, Gröbner algorithm works only for polynomials and moreover for a large scale network, it takes a long CPU time. Hence, we present two other algorithms that work for non-polynomials and large scale problems. Three examples are presented to show the effectiveness of Gröbner basis method compared with Hardy Cross method, linear theory and Gradient method. 相似文献
939.
Fakhar Majid Khodakhah Mohammadreza Mazyaki Ali Soubeyran Antoine Zafarani Jafar 《Journal of Global Optimization》2022,82(1):161-177
Journal of Global Optimization - This paper has two aspects. Mathematically, in the context of global optimization, it provides the existence of an optimum of a perturbed optimization problem that... 相似文献
940.