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171.
172.
Khalil Tabatabaeian Abdollah Fallah Shojaei Farhad Shirini Seyyedeh Zoha Hejazi Mehdi Rassa 《中国化学快报》2014,25(2):308-312
An efficient, convenient and environmentally benign one-pot multicomponent reaction for the preparation of pyrimido[4,5-b]quinoline derivatives as biologically, pharmacologically and antibacte- rially active products has been developed using RuC13.xH20 as a reusable homogenous catalyst. Use of water as a green solvent, purification of products by non-chromatographic methods, reusability of transition metal homogenous catalyst, saving energy by employing multicomponent reactions, short reaction times and high yields, are some of the advantages of this process. 相似文献
173.
Forugh Gudarzy Abdolmajid Bayandori Moghaddam Shahla Mozaffari Yadolah Ganjkhanlou Mahmood Kazemzad Reza Zahed Farhad Bani 《Mikrochimica acta》2013,180(13-14):1257-1262
We report on a novel luminescent method for the detection of folic acid (FA), a member of the vitamin B family. Y2O3 nanoparticles were doped with europium(III) ions and surface-modified with captopril. Their fluorescence is quenched by FA, and intensity is a function of folic acid concentration in the 0.1 – 40 μM concentration range. The detection limit is 83 nM of FA at pH 7 and room temperature. Figure
In this work, we propose a novel method based on the changes in the fluorescence intensity of nanoparticles. Modified Eu-doped Y2O3 nanoparticles by captopril have been used as a probe for the detection of folic acid. 相似文献
174.
An efficient one‐pot approach to the synthesis of 5,7,8,9,9a,10‐hexahydro‐8‐thioxopyrido[2,3‐d : 6,5‐d′]dipyrimidine‐2,4,6(1H,3H,5aH)‐triones 5 via a four‐component reaction of an aldehyde 1 , an amine 2 , a barbituric acid 3 , and thiouracil ( 4 ) is reported for the first time. This new multicomponent reaction is accomplished in refluxing EtOH in the presence of tungstophosphoric acid (H3PW12O40) as a catalyst. A variety of hexahydropyrido[2,3‐d : 6,5‐d′]dipyrimidinetrione derivatives were successfully synthesized in excellent yields with this protocol (Table 2). 相似文献
175.
The oxidation of benzylic alcohols and aldehydes by NaBrO3 is efficiently promoted in the presence of NaHSO4 · H2O. All reactions were performed under mild and completely heterogeneous conditions in good to high yields. 相似文献
176.
Mahmood Tajbakhsh Moslem-Mansor Lakouraj Mohammad-Hosein Gholami Farhad Ramzanian-Lehmali 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1731-1736
Deprotection of phenylhydrazones and semicarbazones to their parent aldehydes and ketones in high yields has been carried out using caro's acid supported on silica gel as a selective oxidant under mild conditions. 相似文献
177.
Thermal degradation behavior of multi-wall carbon nanotubes (MWCNTs)/ultra high molecular weight polyethylene (UHMWPE) nanocomposites, with different nanotubes contents (0.5, 1.5 and 3.5 wt%) prepared via in-situ polymerization technique have been investigated using thermal gravimetric analysis (TGA). TGA spectra revealed that these nanocomposites had enhanced thermal stability and no significant mass loss (<0.4 wt%) occurred up to 350°C. Thermal degradation of these UHMWPE/MWCNT nanocomposites was investigated in terms of parameters such as the onset temperature of degradation (T10), the decomposition temperature at 50% wt loss (T50), the degradation temperature of maximum rate of the weight loss (Tm), and the residual yields (WR) from TGA. The degradation activation energies (E) of virgin UHMWPE and its nanocomposites were estimated using the Friedman, the Ozawa, Flynn, and Wall (OFW), and the Kissinger's methods. Results indicated that the degradation activation energy for the virgin UHMWPE was 281.3 kJ/mol. The activation energy increased with increasing nanotube loading up to 1.5 wt% indicating that MWCNTs had a stabilizing effect on the degradation of the matrix. However, loadings of 3.5 wt% of nanotube or more could slightly decrease the activation energy. The decrease in the activation energy for degradation of nanocomposites with higher MWCNT concentrations might be attributed to the catalytic effects of nanotubes and polymerization catalyst residues. The “model fitting” method indicated a mechanism of n th-order auto-catalysis from the form of the conversion curves for UHMWPE/MWCNTs nanocomposites prepared via in-situ polymerization. 相似文献
178.
179.
Farhad Shirini Somayeh Akbari-Dadamahaleh Ali Mohammad-Khah Ali-Reza Aliakbar 《Comptes Rendus Chimie》2013,16(3):207-216
Rice husk, as a green and cheap reagent, can be used for the promotion of the synthesis of 12-aryl -8, 9,10,12-tetrahydrobenzo[α] xanthen-11-one derivatives (ATXOs) via three-component reaction of aldehydes, 2-naphthol and 5,5-dimethyl-1,3-cyclohexadione (dimedone) under solvent-free conditions. This catalyst can also be used for the preparation of quinoxaline derivatives in a mixture of H2O and CH3CN at 50 °C. The present methodology offers several advantages such as high yields, simple procedure, low cost, short reaction times, mild reaction conditions and use of a green, cheap and reusable catalyst. 相似文献
180.
Golmohammadi Farhad Amiri Masoud Gharibi Hussein Yousefi Ali Safari Meysam 《Journal of solution chemistry》2020,49(1):16-33
Journal of Solution Chemistry - The aggregation behavior was investigated in mixtures of sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) (anionic-rich catanionic) solutions.... 相似文献