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991.
Yunfeng Xu Chong Zhang Pan Mu Na Mao Xue Wang Qian He Feng Wang Jia-Xing Jiang 《中国科学:化学(英文版)》2017,60(8):1075-1083
Two novel tetra-armed conjugated microporous polymers with different geometries have been designed and synthesized via Suzuki-Miyaura cross coupling polycondensation. Both polymers are stable in various organic solvents tested and are thermally stable. The pyrene-containing polymer of PrPy with the rigid pyrene unit shows a higher Brunauer-Emmet-Teller specific surface area of 1219 m2 g?1 than the tetraphenylethylene-containing polymer of PrTPE (770 m2 g?1), which leads to a high CO2 uptake ability of 3.89 mmol g?1 at 1.13 bar/273 K and a H2 uptake ability of 1.69 wt% at 1.13 bar/77 K. The photocatalytic hydrogen production experiments revealed that PrPy also shows a better photocatalytic performance than PrTPE due to the higher conjugation degree and planar structure, the broader UV-visible (UV-Vis) absorption, the lower photoluminescence lifetime, and the higher specific surface area. 相似文献
992.
Moazameh Peyrovi Mohammadreza Hadjmohammadi 《Journal of the Iranian Chemical Society》2017,14(5):995-1004
A sensitive method for extraction and determination of three organophosphorus pesticides (chlorpyrifos, diazinon, phosalone) using a supramolecular solvent (SUPRAS) made of inverted hexagonal aggregates of alkanol and high-performance liquid chromatography with ultraviolet detection (HPLC–UV) was developed. The studied factors were alkanol amount, THF percentage (v/v), pH and vortex time. According to the full factorial design results, the effective parameters were alkanol amount, THF percentage (v/v) and pH. Then, a CCF was applied to obtain optimal conditions. The optimized conditions were obtained at 100 mg of alkanol, 5% of THF and pH 3.9. The limits of detection of pesticides were 0.5–1.3 ng/mL. The linearity was 1.6–500.0 ng/mL for different pesticides. Relative standard deviations for intra- and inter-day extraction of pesticides were 3.3–5.0 and 5.1–6.3, respectively, for five measurements. The method was also successfully applied for the determination of the pesticides in fruit juice and tap water samples. 相似文献
993.
This study presents an easy and cost-effective flow-based cloud point extraction (CPE) method for determining partial amounts of two organophosphorus pesticides (phosalone and ethion) in seawater by HPLC–UV–Vis. In continues CPE methodology, the effect of the different column packing type such as carbon nanotube, polyacrylonitrile nanofiber and fiberglass on pesticide extraction was investigated. The Triton X-100 was utilized as nonionic surfactant, and moreover, effect of different parameters such as pH, temperature, extraction time, surfactant concentration, type and volume of the eluent solution on the extraction efficiency was optimized. Under optimum conditions, the figures of merit of the method for phosalone and ethion were obtained as: the enrichment factor (172 and 166), line range (0.8–300 and 0.5–300 µg L?1, R 2 = 0.9973 and 0.9982), relative standard deviation in concentration of 200 µg L?1 (%RSD = %5.4 and %7.99, N = 5) and limit of detection (LOD = 0.24 and 0.14 µg L?1). The suggested method was successfully used for determination of phosalone and ethion in Chabahar Bay seawaters with satisfactory results. 相似文献
994.
Gui-Fang Qin Qiong-Yun Qin Bing-Fan Long Dong-Ping Wei Yan-Hui Xu Shan-Ju Bao Xian-Hong Yin 《Journal of the Iranian Chemical Society》2017,14(6):1227-1234
Copper (Cu)(II) complexes were synthesized by Ind-3-COOH combined with N-containing auxiliary ligands via a combinatorial strategy involving hydrothermal and solvent-evaporation method. The synthesized complexes had the following formulas: [Cu(Ind-3-COO)2] (1), [Cu(PHEN)(Ind-3-COO)]2·2H2O (2), [Cu2(DPP)(Ind-3-COO)2(H2O)]·H2O, (3) and [Cu(BPY)(Ind-3-COO)2]·4H2O (4). Meanwhile, the symbol abbreviations were listed as follows: Ind-3-COOH = 1H-indazole-3-carboxylic acid, 1,3-bis(4-pyridyl)propane (DPP), 1,10-phenanthroline (PHEN) and 4,4′-bipyridine (BPY). The crystalline structure and spectroscopy of each complex were characterized by single-crystal X-ray diffraction, elemental analysis, Fourier transform infrared spectroscopy and powder X-ray diffraction. The redox reactions in the complexes were then investigated by performing cyclic voltammetry under nitrogen conditions at room temperature. Two pairs of distinctive irreversible reduction potentials were identified, which could be attributed to the processes of Cu(II)–Cu(I) and Cu(I)–Cu(0). 相似文献
995.
Hossein Azizi-Toupkanloo Sayyed Faramarz Tayyari Paul Nancarrow 《Journal of the Iranian Chemical Society》2017,14(6):1281-1300
This work is aimed at providing physical insights about the interactions of cations, anion, and ion pairs of four imidazolium-based ionic liquids of \(\left[ {{\text{C}}_{\text{n}} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\) with varying alkyl chain lengths (n = 2, 4, 6, and 8) using both DFT calculations and vibrational spectroscopic measurements (IR absorption and Raman scattering) in the mid- and far regions. The calculated Mulliken charge distributions of \(\left[ {{\text{C}}_{\text{n}} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\) ion pairs indicate that hydrogen-bonding interactions between oxygen and nitrogen atoms (more negative charge) on \(\left[ {{\text{NTF}}_{2} } \right]^{ - }\) anion and the hydrogen atoms (more positive charge) on the imidazolium ring play a dominating role in the formation of ion pair. Thirteen stable conformers of \(\left[ {{\text{C}}_{2} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\) were optimized. According to our results, the strongest and weakest hydrogen bonds were existing in \(\left[ {{\text{C}}_{2} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\) and \(\left[ {{\text{C}}_{8} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\), respectively. A redshift of 290, 262, 258, and 257 cm?1 has been observed for cations involving \(\left[ {{\text{C}}_{2} {\text{mim}}} \right]^{ + }\), \(\left[ {{\text{C}}_{4} {\text{mim}}} \right]^{ + }\),\(\left[ {{\text{C}}_{6} {\text{mim}}} \right]^{ + }\), and stretching vibrations of \({\text{C}}12{-}{\text{H}}3\), respectively. By increasing the chain length, the strength of hydrogen bonds decreases as a result of \({\text{C}}12{-}{\text{H}}3\) bond elongation and less changes are observed in stretching vibrations of \({\text{C}}12{-}{\text{H}}3\) compared to the free cations. To the best of our knowledge, this research is the first work which reports the far-IR of \(\left[ {{\text{C}}_{4} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\), \(\left[ {{\text{C}}_{6} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\), and \(\left[ {{\text{C}}_{8} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\) and the mid-IR of \(\left[ {{\text{C}}_{8} {\text{mim}}} \right]\left[ {{\text{NTF}}_{2} } \right]\). 相似文献
996.
Mohammad Bakherad Rahele Doosti Ali Keivanloo Mostafa Gholizadeh Khosrow Jadidi 《Journal of the Iranian Chemical Society》2017,14(12):2591-2597
The catalyst-free multi-component reactions of aldehydes, malononitrile, and sodium azide at a relatively low temperature in magnetized water provided 5-substituted 1H-tetrazoles in high-to-excellent yields. This method offers the advantages of short reaction times, low costs, quantitative reaction yields, simple work-up, green, and no need for any organic solvent. 相似文献
997.
Mehrnoush Kangani Nourallah Hazeri Malek-Taher Maghsoodlou 《Journal of the Iranian Chemical Society》2017,14(12):2659-2664
An efficient and easy protocol for the one-pot three-component synthesis of phenylbenzo[g]chromenes was developed. The synthesis was achieved by the reaction of aromatic aldehydes, Meldrum’s acid, and 2-hydroxynaphthalene-1,4-dione in the presence of catalytic amount of Co(NO3)2·6H2O at room temperature. The important advantages of this procedure are short reaction times, high yields, easy work-up, reusable catalyst, and no need to column chromatography. 相似文献
998.
Marjan Hematyar Ali Es-haghi Majid Soleimani Ali Rezaie Mokarram 《Journal of the Iranian Chemical Society》2017,14(12):2665-2671
In this work, magnetic solid-phase extraction based on sodium dodecyl sulfate-coated Fe3O4 nanoparticles has been successfully applied for extraction and preconcentration of trace amounts of nystatin from water and vaccine samples prior to high-performance liquid chromatography–ultraviolet detection. Various experimental parameters affecting extraction and recovery of the analyte, such as the amount of sodium dodecyl sulfate, pH of the sample solution, salt concentration, extraction time, sample volume and desorption conditions, were systematically studied and optimized. Under optimized conditions, nystatin was quantitatively extracted. Proper linear range with good coefficient of determination, (R 2 > 0.99) and limit of detection and quantification (based on signal-to-noise ratios of 3 and 10) of 2.0 and 5.0 µg L?1, over the investigated concentration range (5–700 µg L?1), were obtained, respectively. The intra-day and inter-day relative standard deviations at 50 µg L?1 level of NYS were 1.4 and 4.5% based on six replicate determinations. The accuracy of the method was evaluated by recovery measurements on spiked samples. Suitable recoveries of 96–102 and 26–44% were achieved (at spiked levels of 50, 300 and 500 µg L?1) for water and vaccine samples, respectively. 相似文献
999.
Elahe Kazemi Shayessteh Dadfarnia Ali Mohammad Haji Shabani 《Journal of the Iranian Chemical Society》2017,14(9):1935-1944
A novel and efficient sulfadiazine imprinted polymer was synthesized via co-precipitation method and successfully grafted on magnetic multi-walled carbon nanotubes. The synthesized magnetic imprinted polymer was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction analysis, thermal analysis and applied as a sorbent for selective magnetic solid-phase extraction of sulfadiazine. The retained sulfadiazine was eluted by 150.0 µL methanol/acetic acid (6:4) solution and quantified by fiber optic linear array spectrophotometry via formation of a detectable azo dye. All parameters affecting the extraction of sulfadiazine were investigated and optimized. Under the optimized conditions, the method exhibited a linear dynamic range of 2.0–50.0 µg L?1 with a detection limit of 0.56 µg L?1 and enrichment factor of 300.0. The relative standard deviation at 30.0 µg L?1 of sulfadiazine (N = 6) was 2.8 and 4.6% for intra-day and inter-day, respectively. The method was successfully applied to determine sulfadiazine in human urine, honey, milk and environmental water samples. 相似文献
1000.
Ya-sheng Huang Qi-qi Yu Yin Chen Min-jie Cheng Li-ping Xie 《Chemistry Central journal》2017,11(1):120