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921.
Galo Crdenas T. Elizabeth Salgado C. Viviana Vera L. Miguel J. Yacamn 《Macromolecular rapid communications》1996,17(11):775-780
Styrene/ethyl methacrylate (SEMA) colloids were obtained by cocondensation at 77 K of the monomers with several metals such as Au, Pd, In and Sn. The colloids were polymerized with 2,2′-azoisobutyronitrile and dibenzoyl peroxide as radical initiators at 60°C for 3.5 h. A viscosity average molecular weight (104 < M v < 105) was obtained depending upon the metal used. The particle size of these clusters dispersed in the copolymers ranges from 20 to 31 Å. The metal clusters are incorporated in the copolymers. 相似文献
922.
923.
Hashimoto JC Paschoal JA Queiroz SC Ferracini VL Assalin MR Reyes FG 《Journal of AOAC International》2012,95(3):913-922
A simple method using LC/MS/MS was developed and validated to determine residues of malachite green (MG) and leucomalachite green (LMG) in fish fillet. A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) technique was used to perform the sample preparation. The optimal extraction and cleanup conditions were established using an experimental design. The validation parameters obtained to determine both MG and LMG complied with the requirements established by regulatory agencies for the presence of such substances in fish, which establish that the method must attain, at least, a minimum required performance limit of 2 ng/g. The accuracy values ranged between 95 and 107%, and the precision values were lower than 11.2%. The method was used in the analysis of tilapia samples (n = 20) commercialized in Campinas, SP, Brazil. None of the samples presented detectable levels of MG or LMG residues. 相似文献
924.
925.
Melanie Heghmanns Andreas Rutz Yury Kutin Vera Engelbrecht Martin Winkler Thomas Happe Müge Kasanmascheff 《Chemical science》2022,13(29):8704
Correction for ‘The oxygen-resistant [FeFe]-hydrogenase CbA5H harbors an unknown radical signal’ by Melanie Heghmanns et al., Chem. Sci., 2022, 13, 7289–7294, https://doi.org/10.1039/D2SC00385F.The authors realized that incorrect references were cited following the sentence “In conjunction with the signal''s significant width, the frequency dependence clearly indicates spin–spin interaction between the F-clusters.” The correct references are shown below as ref. 1 and 2.Additionally ref. 36 and 37 were reversed in the reference list. The correct ref. 36 is shown below as ref. 3 and the correct ref. 37 is shown below as ref. 4.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
926.
Nunzio Cardullo Vera Muccilli Vita Di Stefano Sonia Bonacci Lucia Sollima Maria Grazia Melilli 《Molecules (Basel, Switzerland)》2022,27(8)
Inulin is considered a dietary fiber and represents a noteworthy ingredient for food biofortification due to its health effects and its neutral taste. The aim of the work was the evaluation of the quality of pasta produced using whole-meal flours of two ancient Sicilian landraces (Senatore Cappelli-CAP and Timilia—TIM) fortified with two types of inulin (long-chain topinambur inulin IT and low-chain chicory inulin IC), at two different levels of substitution (2 and 4%) to evaluate its possible effect on α-amylase inhibition. The color indices L* and a* were mainly influenced by cultivars, while IT improved the sensory attributes, mainly the elasticity sensation, and influenced less the other sensory attributes: adhesiveness, color, odor, taste, and Over Quality Score for both landraces. The cooking quality was linked mainly to the landrace used, due to the very different gluten matrix of CAP and TIM. IC and IT showed promising α-Amy inhibitory activity with comparable IC50 values of 0.45 ± 0.04 and 0.50 ± 0.06 mg/mL. The enrichment of spaghetti with inulin with an inhibitory effect on α-amylase determined the hypoglycemic properties of pasta, thus lowering the corresponding IC50 value. 相似文献
927.
928.
Vera Münch 《Nachrichten aus der Chemie》2002,50(12):1346-1350
929.
The influence of cationic and anionic surfactants and short‐chain alcohols in the mobile phase on the retention of five antioxidants has been studied. The solutes chosen were butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and propyl, octyl, and dodecyl gallates (PG, OG, DG).The surfactants were hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS), and n‐propanol (PrOH) was the selected alcohol. A simple isocratic reversed‐phase method for the antioxidant determination is proposed. Separation of five primary antioxidants takes 18 min with the mobile phase SDS 0.10 M/H3PO4 0.01 M/PrOH 30%. Variation of the percentage of alcohol in the mobile phase permits optimization of the retention times of the antioxidants. Detection limits in the pg range were obtained for the all solutes. The method was used to determine the antioxidants in olive oil at three different levels, giving mean recoveries close to 100% for all the solutes (BHA 102%, PG 99%, OG 99%, DG 99%) except BHT (84%). 相似文献
930.
Dieter Neher Johannes Grüner Vera Cimrov Wolfgang Schmidt Rudy Rulkens Ulrich Lauter 《先进技术聚合物》1998,9(7):461-475
The properties of light-emitting diodes (LEDs) based on organic layers containing mobile ions, so-called light-emitting electrochemical cells (LECs), are reviewed. These devices have some unique properties: their current–voltage characteristics are antisymmetric with respect to the origin and they emit light under both forward and reverse bias. The physical processes involved in the emission from LECs are discussed in terms of a thermodynamic model. Recent work on blends of luminescent and ion-conducting polymers is summarized. In addition, the properties of novel single-component LECs and polyelectrolyte-based devices are presented. The results show that LECs with performances superior to that of conventional LED devices can be fabricated, but questions concerning the transient behavior and degradation mechanisms persist. © 1998 John Wiley & Sons, Ltd. 相似文献