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31.
32.
Yang Y Nesterenko DV Trump RP Yamaguchi K Bartlett PA Drueckhammer DG 《Journal of chemical information and modeling》2005,45(6):1820-1823
Three new virtual databases have been developed for use with the bond-orientation-based database searching program CAVEAT. These consist of a database of trisubstituted monocyclic hydrocarbons having ethyl, vinyl, and phenyl substituents; a database of unsubstituted bicyclic hydrocarbons; and a database of core structures from established combinatorial synthetic methods having hydrogen, ethyl, vinyl, and phenyl substituents at the readily varied positions. Each collection of molecules was subjected to a batch conformational search, minimization, and conversion to a vector database for use with CAVEAT. 相似文献
33.
A 1.0 x 0.4 cm silica based monolithic anion exchanger has been produced and evaluated for use within a miniature gradient suppressed ion chromatography system based upon low-pressure micro-scale peristaltic pumps. 相似文献
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Capillary electrophoresis for the analysis of paralytic shellfish poisoning toxins in shellfish: Comparison of detection methods 下载免费PDF全文
Aemi S. Abdul Keyon Rosanne M. Guijt Andras Gaspar Artaches A. Kazarian Pavel N. Nesterenko Christopher J. Bolch Michael C. Breadmore 《Electrophoresis》2014,35(10):1496-1503
Paralytic shellfish toxins (PSTs) are produced by marine and freshwater microalgae and accumulate in shellfish including mussels, oysters, and scallops, causing possible fatalities when inadvertently consumed. Monitoring of PST content of shellfish is therefore important for food safety, with currently approved methods based on HPLC, using pre‐ or postcolumn oxidation for fluorescence detection (HPLC‐FLD). CE is an attractive alternative for screening and detection of PSTs as it is compatible with miniaturization and could be implemented in portable instrumentation for on‐site monitoring. In this study, CE methods were developed for C4D, FLD, UV absorption detection, and MS—making this first report of C4D and FLD for PSTs detection. Because most oxidized toxins are neutral, MEKC was used in combination with FLD. The developed CZE‐UV and CZE‐C4D methods provide better resolution, selectivity, and separation efficiency compared to CZE‐MS and MEKC‐FLD. The sensitivity of the CZE‐C4D and MEKC‐FLD methods was superior to UV and MS, with LOD values ranging from 140 to 715 ng/mL for CZE‐C4D and 60.9 to 104 ng/mL for MEKC‐FLD. With the regulatory limit for shellfish samples of 800 ng/mL, the CZE‐C4D and MEKC‐FLD methods were evaluated for the screening and detection of PSTs in shellfish samples. While the CZE‐C4D method suffered from significant interferences from the shellfish matrix, MEKC‐FLD was successfully used for PST screening of a periodate‐oxidized mussel sample, with results confirmed by HPLC‐FLD. This confirms the potential of MEKC‐FLD for screening of PSTs in shellfish samples. 相似文献
36.
Brendan J. Holland Jacqui L. Adcock Pavel N. Nesterenko Anton Peristyy Paul G. Stevenson Neil W. Barnett Xavier A. Conlan Paul S. Francis 《Analytica chimica acta》2014
Sodium polyphosphate is commonly used to enhance chemiluminescence reactions with acidic potassium permanganate through a dual enhancement mechanism, but commercially available polyphosphates vary greatly in composition. We have examined the influence of polyphosphate composition and concentration on both the dual enhancement mechanism of chemiluminescence intensity and the stability of the reagent under analytically useful conditions. The average chain length (n) provides a convenient characterisation, but materials with similar values can exhibit markedly different distributions of phosphate oligomers. There is a minimum polyphosphate chain length (∼6) required for a large enhancement of the emission intensity, but no further advantage was obtained using polyphosphate materials with much longer average chain lengths. Providing there is a sufficient average chain length, the optimum concentration of polyphosphate is dependent on the analyte and in some cases, may be lower than the quantities previously used in routine detection. However, the concentration of polyphosphate should not be lowered in permanganate reagents that have been partially reduced to form high concentrations of the key manganese(III) co-reactant, as this intermediate needs to be stabilised to prevent formation of insoluble manganese(IV). 相似文献
37.
V. P. Nesterenko K. P. Aref'ev V. I. Merkulov A. A. Kondratyuk A. V. Petrov 《Russian Physics Journal》2003,46(2):157-160
The electric strength of a polyoxide mass obtained on the surface of hard alloy composite materials by their high-temperature heating in an electric furnace with direct access of atmospheric air is studied. 相似文献
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We substantiate the application of the projection-iterative method to the solution of a boundary-value problem for integro-differential
equations with restrictions and control.
Translated from Neliniini Kolyvannya, Vol. 12, No. 1, pp. 83–91, January–March, 2009. 相似文献
40.
A. A. Shalimov A. M. Nesterenko L. I. Nesterov A. Yu. Petin A. D. Sinitsa 《Russian Journal of General Chemistry》2009,79(10):2108-2112
Reactions of N-acetyltrifluoroacetamide with chlorophosphites give rise to O-phosphorylated N-trifluoroacetoacetylimidates, which transform into α-phosphorylated vinylamides of trifluroacetic acid as a result of vinylphosphite-vinylphosphonate
rearrangement. On the basis of nonempirical calculations data the reaction protocol of N-acetyltrifluoroacetamide with chlorophosphites was suggested. 相似文献