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31.
Metwally Nadia H. Abdelrazek Fathy M. Eldaly Salwa M. 《Research on Chemical Intermediates》2016,42(2):1071-1089
Research on Chemical Intermediates - The starting 3-(3,5-dimethyl-1H-pyrazol-1-yl)-3-oxopropanenitrile (1) reacts with phenyl isothiocyanate and ethyl bromoacetate to give the corresponding... 相似文献
32.
Nadia Lahrichi Teodor Gabriel Crainic Michel Gendreau Walter Rei Louis-Martin Rousseau 《The Journal of the Operational Research Society》2015,66(1):44-56
The dairy transportation problem (DTP) consists of determining the best routes to be performed for collecting milk from farms and delivering it to processing plants. We study the particular case of the province of Quebec, where the Fédération des producteurs de lait du Québec is responsible for negotiating the transportation costs on behalf of producers. Several issues are highlighted in the actual process of designing contracts such as using historical data. We propose an approach based on scenario analysis that consists of revising both the steps and the information used to construct the routes. We develop a generalized tabu search algorithm that integrates the different characteristics of the DTP. 相似文献
33.
Birendra Kumar Deepti Tikariha M. L. Satnami Nadia Barbero Pierluigi Quagliotto Kallol K. Ghosh 《Journal of Physical Organic Chemistry》2014,27(7):613-621
The catalytic hydrolysis of bis(4‐nitrophenyl)phosphate (BNPP) and bis(2,4‐dinitrophenyl)phosphate (BDNPP) catalyzed by α‐nucleophiles in gemini micellar media was investigated at 27 °C. The cationic gemini surfactants, i.e., alkanediyl‐α‐ω‐bis(hydroxyethylmethylhexadecylammonium bromide) (16‐s‐16 MEA 2Br?, where s = 4 and 6) were used. Nucleophilic reactivity of α‐nucleophiles such as hydroperoxide (HOO?), acetohydroxamate (AHA?), and butane 2,3‐dione monoximate ions (BDMO?) were compared. The kinetic rate data were treated by applying the pseudophase model. The cationic gemini surfactants show unusual rate acceleration toward the cleavage of phosphodiesters with nucleophiles. These studies reveal that the hydroperoxide ion shows the highest catalytic activity reported so far with an unprecedented acceleration rate, 107 times faster than that of the uncatalyzed reaction. The possible mechanism for the BNPP and BDNPP cleavage promoted by α‐nucleophiles is proposed on the basis of kinetic analysis. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
34.
Korany Mohamed Abdel Tawab Moneeb Marwa Said Selim Dina Ahmed Asaad Aya Mohamed El-Sebakhy Nadia Abdel Aziz 《平面色谱法杂志一现代薄层色谱法》2016,29(2):148-154
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
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Nadia Balucani Laura Cartechini Zahra Homayoon Joel M. Bowman 《Molecular physics》2015,113(15-16):2296-2301
Following a recent investigation on the N(2D) + H2O reaction [Homayoon et al., J. Phys. Chem. Lett. 5, 3508 (2014)], we report on an experimental and theoretical study of the isotopologue N(2D) + D2O reaction. Crossed molecular beam (CMB) experiments were conducted at a collision energy of 10.3 kcal mol–1. Quasiclassical trajectory calculations were performed on a recent potential energy surface to derive the centre-of-mass functions necessary to simulate the CMB laboratory distributions. Excellent agreement was found. The importance of the channel leading to HON/DON was confirmed. The inclusion of this channel, in addition to that leading to the isomer HNO/DNO, can affect the models considering the coupling between nitrogen and oxygen chemistry in the upper atmosphere of Titan. 相似文献
38.
Nadia R. Mohamed 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):683-691
N-(chloro-furan-2-yl)methylene-N′-(4-nitrophenyl)hydrazone (I) reacted with triethylphosphite to produce the phosphonate derivative III. The tetrazine derivative VI was produced by the interaction of I with diethyl-phosphite. Hydrazonoyl azide derivatives VIIIa–c reacted with triphenyl phosphine to form the iminophosphorane derivatives Xa–c. On the other hand, the azide derivative VIIIc reacted with the phosphonium ylide XI to form the 1,2,3-triazole adduct XIII. The reaction of triethyl phosphite with Shiff's bases XIVa–c yielded the corresponding phosphonates XVa–c. The structures of the newly prepared compounds were confirmed with the analytical and spectroscopic evidences. 相似文献
39.
Vittorio Elia Nadia Marchettini Elena Napoli Marcella Niccoli 《Journal of Thermal Analysis and Calorimetry》2013,114(2):927-936
This study presents some experimental results on the variation of the physico-chemical properties of pure MilliQ water, when subjected to a procedure of iterated filtration through Millipore filters with porosity ranging from 450 to 25 nm. The parameters measured were: calorimetry, electrical conductivity, density, and pH. Release of chemical impurities can be ruled out due to the nature of the materials used. As in the case of iteratively filtered water prepared using Pyrex glass filters, the specific electrical conductivity and the pH were found to increase with increasing number of iterations. There was also a dependence on the average pore size of the filters. The idea of water as a system capable of self-organization triggered by various perturbations (mechanical and/or electromagnetic) is gaining momentum. It responds to such perturbations by forming dissipative structures, i.e., far-from-equilibrium systems. 相似文献
40.
Serguei Ilchenko Stephen F. Previs Nadia Rachdaoui Belinda Willard Arthur J. McCullough Takhar Kasumov 《Journal of the American Society for Mass Spectrometry》2013,24(2):309-312
The study of protein kinetics requires an accurate measurement of isotopic ratios of peptides. Although Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometers yield accurate mass measurements of analytes, the isotopologue ratios are consistently lower than predicted. Recently, we demonstrated that the magnitude of the spectral error in the FT-ICR mass spectrometer is proportional to the scan duration of ions. Here, we present a novel isotopic ratio extrapolation (IRE) method for obtaining accurate isotopic ratio measurements. Accuracy is achieved by performing scans with different duration and extrapolation of the data to the initial moment of the ion rotation; IRE minimizes the absolute isotopic ratio error to ≤1 %. We demonstrate the application of IRE in protein turnover studies using 2H2O-metabolic labeling. Overall, this technique allows accurate measurements of the isotopic ratios of proteolytic peptides, a critical step for enabling routine studies of proteome dynamics. 相似文献