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71.
Parviz Norouzi Gholam-Reza Nabi Bidhendi Mohammad Reza Ganjali Ali Sepehri Maryam Ghorbani 《Mikrochimica acta》2005,149(1-2):123-129
A novel chemiluminogenic reagent, refered to as spiro form fluorescein hydrazide, was synthesized, and its application to chemiluminescence (CL) determination of Co2+ is described. The method is based on the catalytic effect of Co2+ on the autoxidation of sulfite in basic solution to generate a series of powerful oxidative intermediates, which then oxidize colorless, nonfluoresent fluorescein hydrazide to generate strong CL emission. The CL signal is linearly related to the concentration of Co2+ in the range of 0.1–200nM with a detection limit of 0.04nM. The optimal conditions for the detection of Co2+ were evaluated, and the possible CL mechanism is discussed. The proposed method has been applied to the determination of Co2+ in pharmaceutical preparations and in soil samples. 相似文献
72.
Arash Ghorbani‐Choghamarani Mohsen Nikoorazm Hamid Goudarziafshar Zahra Naserifar Parisa Zamani 《中国化学》2011,29(4):731-734
A mixture of ammonium nitrate or nitro urea and silica sulfuric acid was found to be efficient and environmentally friendly nitrating media for the preparation of orto‐nitro phenols in dichloromethane at room temperature. 相似文献
73.
74.
Mohammad Ali Zolfigol Farhad Shirini Arash Ghorbani Choghamarani Iraj Mohammadpoor-Baltork 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1709-1715
A combination of silica chloride and sodium nitrite in the presence of wet SiO 2 were used as an effective oxidizing agent for the oxidation of dihydropyridines to their corresponding pyridine derivatives under mild and heterogeneous conditions in moderate to excellent yields. 相似文献
75.
Mohammad Ali Zolfigol Arash Ghorbani Choghamarani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1623-1629
A combination of silica sulfuric acid and sodium nitrite in the presence of wet SiO 2 was used as an effective nitrosating agent for the nitrosation of g -diketones to their corresponding f -nitroso or f -oximinoketones under mild and heterogenous conditions in moderate to excellent yields. 相似文献
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77.
M. A. Sutton F. Matta D. Rizos R. Ghorbani S. Rajan D. H. Mollenhauer H. W. Schreier A. O. Lasprilla 《Experimental Mechanics》2017,57(1):1-30
Since presentation of the 2013 Murray Lecture focusing on developments in digital image correlation (DIC), the methods have continued to expand internationally and their use has begun to grow in fields where there was less activity in the past. First, a brief history of digital image correlation methods is presented from the perspective of the first author, followed by a discussion of recent trends associated with the use of digital image correlation methods in academics, governmental laboratories and industrial settings. In the remainder of the article, new results are provided in three areas where DIC methods have seen rapid growth; application of StereoDIC or three-dimensional DIC (3D-DIC) to the study of wall structures in civil engineering; the use of Volumetric DIC or Digital Volume Correlation (DVC) to quantify the internal response of a specially-designed composite material and in the area of model validation for another application in civil engineering; transfer length measurements in pre-stressed concrete beams. 相似文献
78.
79.
Synthesis and X‐ray structural characterization of a bidendate phosphine (dppe) palladium(II) complex and its application in Stille and Suzuki cross‐coupling reactions 下载免费PDF全文
Ali Naghipour Arash Ghorbani‐Choghamarani Heshmatollah Babaee Behrouz Notash 《应用有机金属化学》2016,30(12):998-1003
The synthesis, characterization, crystal structure and catalyst activity of the bidentate phosphine complex [1,2‐bis(diphenylphosphino)ethane]palladium(II) bromide, [PdBr2(dppe)], are presented. Treatment of 1,2‐bis(diphenylphosphino)ethane with palladium(II) bromide under mild conditions resulted in the compound in high yield and purity. The characterization of the synthesized compound was performed using spectroscopic methods, such as Fourier transform infrared and NMR, CHN analysis and X‐ray crystallography. The structure of the compound was slightly distorted square planar. This compound was found to work as an efficient catalyst for both Stille and Suzuki cross‐coupling reactions of various aryl halides with triphenyltin chloride and/or phenylboronic acid. Also, the catalyst could be recovered and reused several times without significant loss of its catalytic activity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
80.
Green and effective route for the synthesis of monodispersed palladium nanoparticles using herbal tea extract (Stachys lavandulifolia) as reductant,stabilizer and capping agent,and their application as homogeneous and reusable catalyst in Suzuki coupling reactions in water 下载免费PDF全文
Hojat Veisi Ramin Ghorbani‐Vaghei Saba Hemmati Majid Haji Aliani Turan Ozturk 《应用有机金属化学》2015,29(1):26-32
A simple and eco‐friendly procedure has been devised for the green synthesis of palladium nanoparticles, using the aqueous extract of herbal tea (Stachys lavandulifolia), a renewable and nontoxic natural phyto‐exudate. The water‐soluble components of the extract act as reducing agent and stabilizer. This green route does not require a surfactant or capping agent for the growth of palladium nanoparticles. The generated nanoparticles were analysed using UV–visible spectroscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X‐ray analysis and inductively coupled plasma. The palladium nanoparticles having spherical shape and dimensions of between 5 and 7 nm were employed as a homogeneous catalyst for Suzuki coupling reactions conducted in water under mild conditions. Good yields of products, a facile work‐up, no evidence of leached palladium from the catalyst surface and smooth recovery of the catalysis by adding ethyl acetate, which could be reused at least eight times, confirm the very good efficiency of the catalytic reaction. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献