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951.
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Hossein Eshghi Zinat Gordi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):619-623
Abstract A rapid and efficient procedure is developed for a one-pot synthesis of nitriles by condensation of aldehydes with hydroxylamine hydrochloride in the presence of P2O5/SiO2 in solvent-free media under microwave irradiation. 相似文献
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Attiq-Ur-Rehman Mohammad Yaqoob Abdul Nabi 《International journal of environmental analytical chemistry》2013,93(9):603-612
A simple and rapid flow injection (FI) method is reported for the determination of arsenic(V) based on luminol chemiluminescence (CL) detection. The molybdoarsenic heteropoly acid formed by arsenic and ammonium molybdate in the presence of ammonium vanadate in acidic conditions generated chemiluminescence emission via the oxidation of luminol. The limit of detection was 0.15 μg L?1, with a sample throughput 120 h?1. A linear calibration graph was obtained over the range 0.15 to 7.5 μg L?1 (r 2 = 0.9989; n = 9) with relative standard deviation (n = 4) in the range 0.8 to 2.5%. Interfering cations were removed by passing the sample through an in-line iminodiacetate chelating column and phosphate (at 0.6 mg L?1) was removed off-line by magnesium-induced coprecipitation (MAGIC) method. The method was applied to freshwater samples and the results obtained were in reasonable agreement with the results obtained using HGAAS as the reference method. 相似文献
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Hossein Reza Darabi Kioumars Aghapoor Kourosh Tabar-Heydar Masoud Nooshabadi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1189-1192
The effect of substrates on the Willgerodt-Kindler reaction was studied. The existence of acidic protons on these substrates accerelates the formation of thiomorpholide was found. 相似文献
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Mohammad Ali Zolfigol Maryam Kiany Borazjani Shadpour E Mallakpour Hossein Nasr-isfahani 《合成通讯》2013,43(14):2573-2585
A combination of inorganic acidic salts or silica gelsupported inorganic acids and sodium nitrite in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of urazoles and bis-urazoles to their corresponding triazolinediones under mild and heterogenous conditions in good yields. Silica gel supported nitric acid and ceric ammonium nitrate (CAN) are also capable of effecting these oxidations in the absence of sodium nitrite in moderate to good yields. Mg(HSO4)2 is a superior to all the aforementioned reagents in convenience, yield and purity of the isolated triazolinediones. 相似文献
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Ahmad Saudi Mohammad Rafienia Anousheh Zargar Kharazi Hossein Salehi Ali Zarrabi Mehdi Karevan 《先进技术聚合物》2019,30(6):1427-1440
Poly (glycerol sebacate) (PGS) is a thermoset biodegradable elastomer considered as a promising candidate material for nerve applications. However, PGS synthesis is very time and energy consuming. In this study, the PGS pre‐polymer (pPGS) was synthesized using three synthesis times of 3, 5, and 7 hours at 170°C. Fourier transform infrared (FTIR), nuclear magnetic resonance spectroscopy, X‐ray diffraction analysis, and differential scanning calorimetry thermogram were utilized to study the pPGS behavior. Poly (vinyl alcohol) was used as a carrier to fabricate aligned poly (vinyl alcohol)‐poly (glycerol sebacate) (PVA‐PGS) fibers with various ratios (60:40, 50:50, and 40:60) using electrospinning and crosslinked through the thermal crosslinking method. Morphology of the fibers was studied before and after crosslinking using scanning electron microscopy (SEM). FTIR, mechanical properties in the dry and wet state, water contact angle, in vitro degradation, and water uptake behavior of crosslinked scaffolds were also investigated. 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, SEM analysis, and 4′, 6‐diamidino‐2‐phenylindole (DAPI) staining were utilized to determine the biocompatibility of scaffolds. The results show the synthesized pPGS in 3 hours at 170°C is the optimized sample in the terms of chemical reaction. All scaffolds have bead‐free and a uniform fiber diameter. The Young's modulus of crosslinked PVA‐PGS (50:50 and 40:60) fibers is shown to be in the expected range for nerve applications. The cell culture studies reveal PVA‐PGS (50:50 and 40:60) fibers could lead to better cell adhesion and proliferation. The results suggest that PVA‐PGS (50:50 and 40:60) is a suitable and promising biodegradable material in the fabrication of scaffolds for nerve regeneration. 相似文献