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91.
92.
Sajjad Dadashi‐Silab Abdullah Mohamed Asiri Sher Bahadar Khan Khalid A. Alamry Yusuf Yagci 《Journal of polymer science. Part A, Polymer chemistry》2014,52(10):1500-1507
Photoinduced free radical polymerization of vinyl monomers by using semiconductor inorganic nanoparticles (NPs) is investigated. Zinc oxide and iron‐doped zinc oxide were used as photosensitive compounds to initiate the polymerization of acrylamide as a water‐soluble monomer in aqueous environment and methyl methacrylate as an oil‐soluble monomer in organic media under UV‐light irradiation. The method uses photochemically generated electrons and holes from the NPs to form initiating hydroxyl radicals in aqueous media, while tertiary amines and iodonium salt served as coinitiator in organic media. The initiation mechanism in organic media involves hydrogen abstraction or reduction processes via charge carriers, respectively. The kinetic of the polymerization in both environments was studied by means of a photo‐differential scanning calorimetry. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1500–1507 相似文献
93.
Masood Sarwar Saeed Ahmad Sajjad Ahmad Saqib Ali Shafique Ahmed Awan 《Transition Metal Chemistry》2007,32(2):199-203
Copper(II)-pyrrolidine dithiocarbamate (PDTC) complexes having the general formula, [Cu(PDTC)2], [Cu(PDTC)X2]− (where X = Cl−, I−, CN−, SCN−) and [Cu(PDTC)(en)]+ (en = ethylenediamine) have been prepared and characterized by IR spectroscopy and by thermogravimetric analysis (TGA and
DTA). The IR data suggests that coordination of pyrrolidine dithiocarbamate (PDTC) takes place through the two sulphur atoms
in a symmetrical bidentate fashion. The results of thermal analysis are consistent with the proposed composition of the complexes. 相似文献
94.
Sajjad Keshipour Nastaran Kalam Khalteh 《Journal of the Iranian Chemical Society》2016,13(11):1977-1982
A new support for Pd(II) was synthesized via the functionalization of Fe3O4 nanoparticles with N-(2-aminoethyl)acetamide. PdCl2 was anchored to the support for obtaining a heterogeneous magnetically recoverable catalyst for Pd(II). High yield and excellent selectivity were obtained for the green epoxidation of styrene derivatives using H2O2 as a green oxidant in H2O as the solvent at 100 °C. Also, the recovered catalyst is applicable for four times without significant decrease in yield. 相似文献
95.
Farhat Ullah Abdul Sadiq Abid Hussain Sajjad Ahmad Muhammad Imran 《Natural product research》2016,30(12):1440-1444
This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman’s assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively. 相似文献
96.
Liquid-liquid-liquid microextraction (LLLME) in combination with HPLC and UV detection has been used as a sensitive method for the determination of ephedrine in urine samples. Extraction process was performed in a homemade total glass vial without using a Teflon ring, usually employed. Ephedrine was first extracted from 3.5 mL of urine sample (pH 12) into a microfilm of toluene/benzene (50:50). The analyte was subsequently back extracted into an acidic microdrop solution (pH 2) suspended in the organic phase. The extract was then injected into the HPLC system directly. An enrichment factor of 137 along with a good sample clean-up was obtained under the optimized conditions. The calibration curve showed linearity in the range of 0.01-50 mg/L with regression coefficient corresponding to 0.998. The LODs and LOQs, based on a S/N of 3 and 10, were 5 and 10 microg/L, respectively. The method was eventually applied for the determination of ephedrine in urine sample after oral administration of 5 mg single dose of drug. 相似文献
97.
Ethylene polymerization was carried out by using a group of new dizirconium(IV) tetrapyrrole complexes as catalysts and MAO as co-catalyst under 1 atmosphere pressure of ethylene gas at 25 and 40°C. The highest value of catalyst activity was obtained
at 40°C by using bizirconium complexes including one calix[4]pyrrole between two zirconium centers and two terminal chlorines,
while zirconium(IV) complexes with coordinated THF, almost have not catalytic activity. The maximum catalytic activity mounted to 830 kg/mol·bar·h by Zr2(Cy4
Pyr
4)Cl4. The results show that the structure of the coordination sphere of zirconium(IV) has great influence on the rate of polymerization,
molar masses of forming polymer, and its molecular mass distribution.
Correspondence: Sajjad Mohebbi, Chemistry Department, University of Kurdistan, P.O. Box 66176-416, Sanandaj, Iran. 相似文献
98.
Heshmatollah Alinezhad Mahmoud Tajbakhsh Roja Enayati Ahangar 《Monatshefte für Chemie / Chemical Monthly》2008,139(1):21-25
Summary. A chemoselective, fast, efficient, and high yielding method for the preparation of amines by reductive amination of aldehydes
and ketones using sodium borohydride in the presence of silica phosphoric acid in THF and under solvent-free conditions at room temperature is described. 相似文献
99.
100.