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排序方式: 共有278条查询结果,搜索用时 15 毫秒
271.
Aneseh Khalatbari Jafari Reihaneh Kardanpour Shahram Tangestaninejad Valiollah Mirkhani Majid Moghadam Iraj Mohammadpoor-Baltork Farnaz Zadehahmadi 《Journal of the Iranian Chemical Society》2018,15(5):997-1006
In this work, the metallo Schiff base-functionalized metal–organic framework was prepared by post-synthetic method and used as an electron-deficient catalyst for the alcoholysis of epoxides. In this manner, the aminated MIL-101 was modified with 2-pyridine carboxaldehyde and then the prepared Schiff base reacted with RuCl3. This new catalyst, MIL-101–NH2–PC–Ru, was characterized by Fourier transform infrared, UV–Vis spectroscopic techniques, X-ray diffraction, BET, inductively coupled plasma atomic emission spectroscopy and field-emission scanning electron microscopy. In the presence of this heterogeneous catalyst, ring opening of epoxides was performed under mild condition to show the significant ability and successful applications of Lewis acid containing catalysts in corporation with metal–organic frameworks. The reusability of the catalyst was also investigated. No noticeable decrease in the catalytic activity was found after four consecutive times. 相似文献
272.
Abdollah Fallah Shojaei Khalil Tabatabaeian Massome Hamidiyan Seyyedeh Zoha Hejazi 《Journal of the Iranian Chemical Society》2016,13(5):803-808
In this study, new RuO2@ZrO2 core–shell nanoparticles have been produced using simple procedure and characterized by the spectroscopic methods (XRD and HR-TEM techniques). Catalytic activity of the synthesized nano powders has been investigated in the liquid-phase selective oxidation of benzyl alcohols. Also, the effect of some parameters such as optimum weight ratio for Ru doping, catalyst, oxidant type and various solvents was studied in room temperature, reflux, ultrasound, microwave conditions and UV–vis irradiation. The catalyst exhibits excellent activity and high conversion under mild conditions. Furthermore, this reagent was recycled and reused three times in the model reaction. 相似文献
273.
Mahsa Asadniaye Fardjahromi Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor-Baltork 《Journal of the Iranian Chemical Society》2017,14(6):1317-1323
In this paper, we present an efficient and practical method for oxidation of alcohols to their corresponding carbonyl compounds catalyzed by [Mn(salophen)@nSTD]. This catalyst was synthesized, and characterized by FT-IR, UV–Vis, TGA, SEM and TEM. The results of experiments proved that this catalyst has excellent selectivity and high activity in the oxidation of different primary and secondary alcohols to their corresponding aldehyde and ketone at room temperature. The effects of important factors in the oxidation of alcohols such as kind of oxidant, solvent and amount of catalyst were investigated in the oxidation of 4-chlorobenzyl alcohol. This catalyst shows high stability and reusability after six catalytic runs. 相似文献
274.
Fatemeh Shojaei Naemeh Tavakolinia Adeleh Divsalar Thomas Haertlé Ali Akbar Saboury Mohsen Nemat-Gorgani Maria Pia Abbracchio 《Journal of the Iranian Chemical Society》2014,11(6):1503-1512
Protein aggregation is commonly associated with a large number of neurodegenerative disorders such as Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and other types of pathological conditions. Misfolding and aggregation of a number of peptides and proteins have been found to occur under these conditions. In the present review, some mechanistic features of the events related to the type of structure–function relationships which may define the outcome of the abnormal conditions are discussed. The immunological responses to the aggregates and possible therapeutic strategies for prevention or control of the diseases are also reviewed. Protein aggregation and its effect on human body have become an important issue over the last two decades. Many diseases in human are related to aggregation and misfolding of different kinds of proteins; therefore, diagnosis of causes of the aggregation and their mechanisms which provoke it are important. This review describes the relations between structures and functions of already aggregated proteins, as well as proteins, which only enter initial stages of aggregation. The consequences of aggregations, which provoke many kinds of neurodegenerative disorders, are explained in details and some factors that may influence their severity are described. In addition, the immunologic responses to these aggregates are discussed. Suggestions of plausible therapies of preventing or slowing down the protein condensation diseases are presented. 相似文献
275.
A simple, efficient, and rapid sample preparation method based on aeration‐assisted homogeneous liquid–liquid microextraction was developed for determination of curcumin in food samples by high‐performance liquid chromatography. The centrifuge step has been eliminated in this procedure. The effects of some variables, such as pH, volume of extraction solvent, extraction time, and salt effect, were studied through a Box–Behnken design method. Under the optimum conditions, calibration curves of curcumin were linear in the range of 0.08‐4000 μg/mL with R2 = 0.997. Limit of detection and relative standard deviation were 0.019 μg/mL and 3.01%, respectively. The preconcentration factor achieved was 166. The proposed method was successfully applied to determination of curcumin in various food samples. 相似文献
276.
Iraj Mohammadpoor-Baltork Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Hamid Reza Tavakoli 《中国化学快报》2011,22(1):9-12
An efficient,convenient and green method has been introduced for the preparation of 14-aryl(alkyl)-14H-dibenzo[a,j]xanthene and 1,8-dioxooctahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 5,5-dimethyl-1,3-cyclohexanedione, respectively,in the presence of ZrO(OTf)2 as a reusable catalyst under solvent-free conditions.In addition,very short reaction times, excellent yields,straightforward procedure,and relatively non-toxicity of the catalyst are other noteworthy advantages of the present method. 相似文献
277.
Mohammad Ali Zolfigol Iraj Mohammadpoor-Baltork Davood Habibi BiBi Fatemeh Mirjalili Abdolhamid Bamoniri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2189-2193
Trimethylsilyl ethers were converted to their corresponding alcohols in the presence Nafion-H® and wet SiO 2 with good-to-excellent yields under mild and heterogeneous conditions. 相似文献
278.