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In this article, the numerical solution of nonlinear systems using iterative methods are dealt with. Toward this goal, a general class of multi-point iteration methods with various orders is constructed. The error analysis is presented to prove the convergence order. Also, a thorough discussion on the computational complexity of the new iterative methods will be given. The analytical discussion of the paper will finally be upheld through solving some application-oriented problems. 相似文献
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Ansari P Stoppacher N Rudolf J Schuhmacher R Baumgartner S 《Analytical and bioanalytical chemistry》2011,399(3):1105-1115
The aim of this work was the determination of peptides, which can function as markers for identification of milk allergens
in food samples. Emphasis was placed on two casein proteins (α- and β-casein) and two whey proteins (α-lactalbumin and β-lactoglobulin).
In silico tryptic digestion provided preliminary information about the expected peptides. After tryptic digestion of four
milk allergens, the analytical data obtained by combination of reversed-phase high performance liquid chromatography and quadrupole
tandem mass spectrometry (LC-MS/MS) led to the identification of 26 peptides. Seven of these peptides were synthesized and
used for calibration of the LC-MS/MS system. Species specificity of the selected peptides was sought by BLAST search. Among
the selected peptides, only LIVTQTMK from β-lactoglobulin (m/z 467.6, charge 2+) was found to be cow milk specific and could function as a marker. Two other peptides, FFVAPFPEVFGK from
α-casein (m/z 693.3, charge 2+) and GPFPIIV from β-casein (m/z 742.5, charge 1+), occur in water buffalo milk too. The other four peptides appear in the milk of other species also and
can be used as markers for ruminant species milk. Using these seven peptides, a multianalyte MS-based method was developed.
For the establishment of the method, it was applied at first to different dairy samples, and then to chocolate and blank samples,
and the peptides could be determined down to 1 ng/mL in food samples. At the end, spiked samples were measured, where the
target peptides could be detected with a high recovery (over 50%). 相似文献
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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
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Experimental Investigation on Upgrading of Lignin‐Derived Bio‐Oils: Kinetic Analysis of Anisole Conversion on Sulfided CoMo/Al2O3 Catalyst
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Hamid Reza Rahimpour Majid Saidi Parisa Rostami Bruce C. Gates Mohammad Reza Rahimpour 《国际化学动力学杂志》2016,48(11):702-713
Kinetics of the hydroprocessing of anisole, a compound representative of lignin‐derived bio‐oils, catalyzed by a commercial sulfided CoMo/Al2O3, was determined at 8–20 bar pressure and 573–673 K with a once‐through flow reactor. The catalyst was sulfided in an atmosphere of H2 + H2S prior to the measurement of its performance. Selectivity‐conversion data were used as a basis for determining an approximate, partially quantified reaction network showing that hydrodeoxygenation (HDO), hydrogenolysis, and alkylation reactions take place simultaneously. The data indicate that these reactions can be stopped at the point where HDO is virtually completed and hydrogenation reactions (and thus H2 consumption) are minimized. Phenol was the major product of the reactions, with direct deoxygenation of anisole to give benzene being kinetically almost insignificant under our conditions. We infer that the scission of the Cmethyl–O bond is more facile than the scission of the Caromatic–O bond, so that the HDO of anisole likely proceeds substantially through the reactive intermediate phenol to give transalkylation products such as 2‐methylphenol. The data determine rates of formation of the major primary products. The data show that if oxygen removal is the main processing goal, higher temperatures and lower pressures are favored. 相似文献
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Dr. Kiran Sagar Unikela Dr. Parisa Ghods Ghasemabadi Dr. Václav Houska Dr. Louise N. Dawe Dr. Yuming Zhao Dr. Graham J. Bodwell 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(1):390-400
A gram-scale synthesis of a series of 1,1,n,n-tetramethyl[n](2,11)teropyrenophanes (n=7–9) has been accomplished as well as the first synthesis of the next higher homologue 1,1,10,10-tetramethyl[10](2,11)teropyrenophane. The scale-up of the original small-scale synthesis required the development of several heavily modified synthetic methods, including a chlorination/Friedel–Crafts alkylation protocol and an iodination/Wurtz coupling protocol, which were performed on 25–30 g and 30–60 g scales, respectively. Two separate sets of conditions for the key teropyrene-forming cyclodehydrogenation reaction at the end of the synthetic pathway were developed, an acid-promoted one for the two less strained congeners and an acid-free method for the two more strained homologues. 相似文献
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