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41.
In this work, we report the preparation and characterization of novel dye doped fluorophore Eosin yellowish silica nanoparticles
(ESNPs). We synthesized ESNPs by the St?ber method via encapsulation of Eosin Yellowish in silica particles by the condensation
of tetraethyl orthosilicate under alkaline condition at room temperature. The resulted ESNPs were characterized by transmission
electron microscopy, atomic force microscopy; UV–Visible, fluorescence and Fourier transform infrared spectroscopy. The sizes
of the nanoparticles have been found to be 300.0 (±1.0), 400.0 (±1.1) and 500.0 (±5.2) nm depending the reaction conditions
under which they were synthesized. Furthermore, because of intense light emission, the ESNPs were used as fluorophore in a
peroxyoxalate chemiluminescence system. The effect of solvent and concentrations of necessary reagents, bis(2,4,6-trichlorophenyl)oxalate,
sodium salicylate, hydrogen peroxide and the effects of size of the ESNP and temperature on the luminescence efficiency of
the system were examined. The activation kinetic parameters of the system were also evaluated from the temperature investigation. 相似文献
42.
Polyoxometalates (POM) supported on zirconia, H3PW12O40/ZrO2, were prepared by incorporating polyphosphotungstate into a zirconia matrix via sol-gel technique that involving the hydrolysis of zirconium (IV) n-butoxide, Zr (n-OBu)4, as the ZrO2 source. This insoluble and readily separable catalyst was characterized by using XRD, FT-IR, SEM, and UV diffuse reflectance spectroscopy (UV-DRS), indicating that the polyphosphotungstate was chemically attached to the zirconia supports, and primary Keggin structure remained intact. The photocatalytic and sonocatalytic activity of the supported polyphosphotungstate was tested via degradation of different dyes in aqueous solutions. The POM-ZrO2 nanocomposite showed higher photocatalytic and sonocatalytic activity than pure polyoxometalate or pure ZrO2. 相似文献
43.
Nasir Iravani Jalal Albadi Somaieh Varnaseri Zahra Jaberi Nahid Karami Marzieh Khadamati 《中国化学会会志》2012,59(12):1567-1570
A simple and efficient one‐pot synthesis of alkyl 2‐(alkyl)‐4‐methyl‐2‐thioxo‐2,3‐dihydrothiazole‐5‐carboxylates from the reaction of primary alkylamines and carbon disulfide in the presence of 2‐chloro‐1,3‐dicarbonyl compounds is described. This new protocol has several advantages such as lack of necessity of the catalyst, good yields, mild conditions and short times for reaction. 相似文献
44.
Reza Mahmoudi Saeed Aghaei Zeinab Salehpour Ali Mousavizadeh Seyed Sajjad Khoramrooz Marzie Taheripour Sisakht Gunna Christiansen Marzieh Baneshi Bahman Karimi Hassan Bardania 《应用有机金属化学》2020,34(2):e5394
Due to environmentally friendly and cost- effective issues, biological methods for silver nanoparticles (AgNPs) synthesis are advantageous over chemical and physical ones. In this study, AgNPs synthesized using Lavandula stoechas extract as a reductant and its antioxidant capacity, antibacterial property and cytotoxicity effect were investigated. The phyto-synthesized AgNPs were characterized using various analyses such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD) as well as Fourier transform infrared (FT-IR). The prepared nanoparticles were spherical on shape with the size about 20–50 nm. Antibacterial studies through agar disk diffusion method confirmed the antibacterial potential of phyto-synthesized AgNPs toward two clinical Staphylococus aureus and Pseudomonas aeruginosa bacteria, although MTT assay demonstrated that S. aureus (MIC = 125 μg/ml) was more susceptible to AgNPs than P. aeruginosa (MIC = 250 μg/ml). Moreover, the cytotoxicity assay of phyto-synthezied AgNPs showed a low cytotoxic effect on RAW264 cell line at 62.5 μg/ml as an effective concentration. Also the considerable antioxidant capacity of the AgNPs confirmed through DPPH assay. Great antibacterial and antioxidant properties along with biocompatibility make the suggested phyto-synthesized AgNPs a great candidate for different biomedical applications including wound healing. 相似文献
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46.
Rahman Bikas Hossein Farzaneh-Bonab Muhittin Aygün Marzieh Emami Tadeusz Lis 《Journal of Coordination Chemistry》2018,71(8):1127-1146
The hydrazone (E)-3-hydroxy-N’-(1-(2-oxo-2H-chromen-3-yl)ethylidene)-2-naphthohydrazide (H2L) was synthesized from the reaction of 3-acetylcoumarin and 3-hydroxy-2-naphthoic hydrazide in methanol. Compounds [Mn(H2L)(NO3)2(CH3OH)]·CH3OH (1a), [Mn(HL)(NO3)(CH3OH)]n (1b), [Co(HL)(NO3)(CH3OH)]n (2), and [Cu(HL)(NO3)] (3) were obtained by reaction of an equimolar amount of H2L with nitrate salts of Mn(II), Co(II), or Cu(II) in methanol. The reaction of ligand and Mn(NO3)2·4H2O was also carried out in the presence of sodium azide which led to the 1-D coordination polymer, [Mn(HL)(N3)(CH3OH)]n (4). All of the synthesized compounds were characterized by elemental analyses and spectroscopic methods. Single-crystal X-ray analysis of 1–4 indicated that H2L is neutral (in 1a) or mononegative ligand (in 1b, 2, 3 and 4). In 1b, 2 and 4 the 1-D polymeric chain is found by a rare coordination mode of this kind of hydrazone ligand since the naphtholic oxygen is coordinated to the neighboring metal ions while the NH moiety of hydrazone remains intact, also confirmed by FT-IR spectroscopic studies. The thermal stability of 2 and 4 were also studied from 30–1000 °C. 相似文献
47.
A. Vafaee A. Davoodnia M. R. Bozorgmehr M. Pordel 《Journal of Structural Chemistry》2018,59(2):335-343
Several new 4-acetamidoalkyl pyrazoles are synthesized by an efficient, one-pot three-component reaction of 3,5-dimethyl-1-phenyl-1H-pyrazole or 3-methyl-1-phenyl-1H-pyrazol-5-ol, aromatic aldehydes, and acetonitrile in the presence of chlorosulfonic acid at room temperature. The products are characterized based on IR, 1H and 13C NMR data and evaluated as potential COX-2 and B-Raf inhibitors by molecular docking studies. All the products showed the potency of B-Raf and COX-2 inhibitory effects with a greater binding affinity to B-Raf than COX-2 protein. 相似文献
48.
This work introduces a new gradient fiber coating for microextraction of chlorobenzenes. Nanoclusters of organoclay-Cu(II) on a copper wire were fabricated by wireless electrofunctionalization. The resultant gradient coatings are more robust, and thermally and mechanically stable. Wireless electrofunctionalization was carried out in a bipolar cell under a constant deposition potential and using an ethanolic electrolyte solution containing stearic acid and montmorillonite. Stearic acid acts as an inexpensive and green coating while montmorillonite acts as a modifier to impart thermal stability. The gradient morphology of the nanoclusters was investigated by scanning electron microscopy, thermogravimetric analysis and energy dispersive X-ray spectroscopy. The coated wire was placed in a hollow needle and used for headspace in-tube microextraction (HS–ITME) of chlorobenzenes (CBs). Effects of various parameters affecting synthesis and extraction were optimized. Following extraction, the needles were directly inserted into the GC injector, and the CBs (chlorobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3,4-tetrachlorobenzene) were quantified by GC–MS. The limits of detection under optimized conditions range from 0.5 to 10 ng.L?1. The intra– and inter–day relative standard deviations (RSDs) (for n?=?10, 5 respectively) using a single fiber are 6–10 and 10–15%, respectively. The fiber–to–fiber RSDs (for n?=?3) is between 17 and 24%. The method was successfully applied to the extraction of CBs from real water samples, and relative recoveries are between 91 and 110%.
相似文献
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New magnetic supported hydrazone Schiff base dioxomolybdenum (VI) complex: An efficient nanocatalyst for epoxidation of cyclooctene and norbornene 下载免费PDF全文
A new dioxomolybdenum (VI) complex with tridentate hydrazone Schiff base ligand (H2L) derived from 2‐hydroxy‐5‐nitrobenzaldehyde and benzhydrazide was synthesized and designated as [MoO2L (DMF)]·2H2O. The Fe3O4@SiO2‐CPS‐L‐MoO2 (EtOH) nanocatalyst was successfully prepared by grafting H2L ligand on modified Fe3O4 nanoparticles followed by reacting with MoO2 (acac)2. The complex and nanocatalyst were characterized by various techniques such as elemental analysis, mass, FT‐IR, UV–Vis, 1H NMR, 13C{1H}‐NMR, TGA, XRD, XPS, TEM, SEM and VSM. The catalytic activity of [MoO2L (DMF)]2H2O and Fe3O4@SiO2‐CPS‐L‐MoO2 (EtOH) were evaluated for the oxidation of various alkenes (cyclooctene, norbornene, cyclohexene, styrene and α‐methyl styrene) in the presence of tert‐butylhydroperoxide as oxidant. The results revealed that the catalysts were especially efficient for oxidation of cyclooctene and norbornene with 100% selectivity towards corresponding epoxide product. Fe3O4@SiO2‐CPS‐L‐MoO2 (EtOH) showed higher catalytic activity, shorter reaction time and higher turnover number (TON) compared with homogeneous complex [MoO2L (DMF)]·2H2O. Moreover, simple magnetic recovery from the reaction mixture and reuse for several times with no significant loss in activity were other advantages of the nanocatalyst. 相似文献