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121.
Mahmood Tajbakhsh Majid M. Heravi Abolfazl Hosseini Ahmad Shahrezaiee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):773-776
Hantzsch 1,4-dihydropyriines were rapidly and efficiently oxidized using bismuth nitrate supported onto silica gel under microwave irradiation. 相似文献
122.
Afshan Siddiqui Kajal Singh Kanchan Lata Singh Shailendra Kumar Gupta Mohd Safi Ahmad U. N. Tripathi 《应用有机金属化学》2012,26(5):203-211
Mixed ligand complexes of Iron(III) with aspartic acid and 3(2′‐hydroxy phenyl)‐5‐(4′‐substituted phenyl) pyrazolines of type [Fe(C4O4NH6)2(C15H12N2OX)] and [Fe(C4O4NH6)(C15H12N2OX)2], where (C4O4NH6) = aspartate, (C15H12N2OX) = deprotonated 3(2′‐hydroxyphenyl)‐5‐(4′‐substituted phenyl) pyrazolines (X = H, CH3, OCH3, Cl), have been synthesized. These newly synthesized derivatives have been physicochemically characterized by elemental analysis (C, H, N, Cl and Fe), magnetic moment data, thermogravimetric analysis, molar conductance, cyclic voltammetry, spectral analysis (UV–visible, IR, far IR and fast atom bombardment mass spectrometry). Scanning electron microscopy, transmission electron microscopy and X‐ray powder diffraction studies have been carried out for powdered samples, which show nanometric particles of these derivatives. Antibacterial and antifungal potential of free pyrazoline and some iron(III) complexes have been evaluated. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Ahmad Alshammari Naif Alarifi Marzook Alshammari Manzar Sohail Rashid Altamimi 《Journal of Saudi Chemical Society》2019,23(7):999-1005
The development of base metal catalysts for industrially important reactions continues to be an important goal of catalysis research. Herein, the effects of pyrolysis temperature on the textural, structural, surface, magnetics properties and catalytic properties of silica-supported nickel nanoparticles (NiNPs) were thoroughly investigated. Mono-dispersed NiNPs encapsulated in graphitic shells were first successfully obtained and were characterized using a variety of methods such as BET surface area measurement, CO-pulse chemisorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high resolution transmission electron microscopy (HR-TEM), and superconducting quantum interference device (SQUID) measurement. The findings showed that all catalysts’ properties were considerably altered with change in pyrolysis temperature. Hydrogenation of diphenylacetylene was then selected as the model reaction for the evaluation of the catalytic performance of the graphitic-shelled NiNPs. After testing, pyrolysis of a nickel at 800 °C (catalyst A) displayed tremendous activity and selectivity to produce >94% of stilbene with selectivities of 99% for the Z-isomer. 相似文献
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We demonstrate a switchable Q-switched and mode-locked erbium-doped fiber laser (EDFL) operating in the L-band region using the nonlinear polarization rotation effect. The switching operation is achieved by controlling intensity-dependent loss using a polarization controller. In Q-switching mode, the EDFL produces a pulse train with a repetition rate of 21.1 kHz, pulse width of 7.7 #s, and pulse energy of 13.6 nJ. The EDFL also generates a multi-wavelength comb with a very narrow and constant wavelength spacing of 0.045 nm and optical signal-to-noise ratio of at least l0 dB. During mode locking, the EDFL produces stretched pulses with 3-dB bandwidth of 26.2 nm, pulse width of 350 fs, repetition rate of 2.38 MHz, and pulse energy of 48.56 pJ. 相似文献
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128.
Silver nanoparticles immobilized onto poly(4‐vinylpyridine)‐functionalized magnetic nanoparticles: A robust magnetically recyclable catalyst for oxidant‐free alcohol dehydrogenation 下载免费PDF全文
A heterogeneous and recyclable catalyst with a high loading of silver nanoparticles was synthesized via the silver nanoparticles being supported onto the surface of magnetic nanoparticles coated with poly(4‐vinylpyridine). The synthesized catalyst was used in the dehydrogenation of alcohols to corresponding carbonyl compounds. A broad diversity of alcohols was converted into their corresponding carbonyl compounds in excellent yields. The catalyst was easily recovered by applying an external magnetic field and reused for seven reaction cycles without considerable loss of activity. The catalyst was fully characterized using various techniques. 相似文献
129.
Ahmad A. SalaimehJeffrey J. Campion Belal Y. Gharaibeh Martin E. Evans Kozo Saito 《Infrared Physics & Technology》2012,55(1):170-172
We previously showed that infrared thermography (IRT) could be used to quantify viable Escherichiacoli, a representative gram-negative bacterium, in liquid growth media. Here, we evaluated the ability of IRT to enumerate a viable representative gram-positive organism, Staphylococcusaureus. We found that the energy content (EC) of the media was strongly positively correlated (r = 0.999) to measured viable counts of S.aureus ranging from 85 colony-forming units (CFU)/ml to ∼4 × 108 CFU/ml. The EC of S.aureus was ∼2-fold higher than that of E.coli at comparable cell concentrations suggesting that IRT may be used to distinguish genera. 相似文献
130.
Mohammad Khorrami Ahmad Shariati Amir Aghamohammadi Amir H. Fatollahi 《Physics letters. A》2012,376(5):687-691
It is shown that as far as the linear diffusion equation meets both time- and space-translational invariance, the time dependence of a moment of degree α is a polynomial of degree at most equal to α, while all connected moments are at most linear functions of time. As a special case, the variance is an at most linear function of time. 相似文献