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101.
McLaurin Teresa Diamantidis Stylianos Diamantidis Iraklis 《Design & Test of Computers, IEEE》2009,26(1):44-51
This article describes the test wrapper implementation of a popular embedded microprocessor, along with an automated approach for verifying the wrapper's compliance to the standard. 相似文献
102.
Adsorption of methyl mercaptan on activated carbons 总被引:1,自引:0,他引:1
Activated carbons of different origins were studied as methyl mercaptan adsorbents in wet, dry, and oxidizing conditions. The materials were characterized using adsorption of nitrogen, Boehm titration, and thermal analysis. Investigation was focused on the feasibility of the removal of methyl mercaptan on activated carbons and on the role of surface chemistry and porosity in the adsorption/oxidation processes. The results showed relatively high capacities of carbons for removal of CH3SH. The amount adsorbed depends on the surface features. Methyl mercaptan, in general, is oxidized to disulfides, which, depending on the chemistry of the carbon surface, can be converted to sulfonic acid due to the presence of water and active radicals. 相似文献
103.
De Angelis M Curtin AC McSweeney PL Faccia M Gobbetti M 《The Journal of dairy research》2002,69(2):255-267
A homo-tetrameric approximately 160-kDa cystathionine gamma-lyase was purified to homogeneity from Lactobacillus reuteri DSM 20016 by four chromatographic steps. The activity was pyridoxal-5'-phosphate dependent and the enzyme catalyzed the alpha,gamma-elimination reaction of L-cystathionine, producing L-cysteine, ammonia and alpha-ketobutyrate. The enzyme was active towards a range of amino acids and amino acid derivatives, including methionine. The pH and temperature optima were found to be 8.0 and 35 degrees C. respectively. Isoelectric pH (pI) was approximately 5.0 as determined by two-dimensional electrophoresis. Sensitivity to chemical inhibitors was typical of lactococcal cystathionine gamma- and beta-lyases, except it was inhibited by sulphydryl reagents. The N-terminal sequence was MKFNTQLIHGGNSED, which had 100% homology with cystathionine beta-lyase of Lb. reuteri 104R (Accession Number (CAC05298). Lb. reuteri DSM 20016. together with 10 other strains of non-starter lactic acid bacteria, was used as adjunct starter in the production of miniature ('anestrato Pugliese-like cheeses. After 40 d ripening, the water-soluble extract of the cheeses with added Lactobacillus fermentum DT41 and Lb. reuteri DSM 20016 contained the highest enzyme activities on cystathionine and methionine substrates. Determinations of methanethiol, dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide in the miniature cheeses confirmed the findings of enzyme activities. 相似文献
104.
Esteves AC Monteiro OC Barros-Timmons AM Boemare C Soares MJ Monteiro T Trindade T 《Journal of nanoscience and nanotechnology》2002,2(2):177-181
Hybrid materials consisting of SiO2/CdS particles dispersed in poly(styrene-co-maleic anhydride) and poly(styrene-co-maleimide) have been synthesized and characterized. The polymer nanocomposites were synthesised in situ in the presence of previously prepared inorganic fillers (SiO2/CdS). The nanocomposites were synthesized with the use of as-prepared or surface-modified SiO2/CdS fillers. For both types of nanocomposites, the optical properties were evaluated and the observation of size quantization effects in the optical spectra is discussed. In this context, the influence of the inorganic fillers and polymer matrices on the optical properties of the final nanocomposites was investigated. 相似文献
105.
Using the measures of initial reaction rate, a kinetic-photometric method is developed that uses the reaction of Diquat with H2O2 in basic medium. The reaction rate is very high and therefore the stopped-flow mixing technique is required in order to make kinetic measurements. The reaction rate is obtained in 20 s after the reactants are mixed and it allows the simple application of the method proposed to the routine analyses. The sensitivity of the method is very high being the detection limit 0.44 microgmL(-1) and the application range between 1 and 16 microgmL(-1). The time of measure per sample is 90s. The proposed kinetic-photometric method has been applied to the direct determination of this compound in river water, in the water of laundry of the olives, and in a commercial product. The results are very acceptable. 相似文献
106.
In this note we study a fixed point iteration approach to solve algebraic Riccati equations as they appear in general two player Nash differential games on an infinite time horizon, where the information structure is of open loop type. We obtain conditions for existence and uniqueness of non‐negative solutions. The performance of the numerical algorithm is shown in an example. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
107.
R. Lyonnet A. Khodan A. Barthe´le´my J.-P. Contour O. Durand J.L. Maurice D. Michel J. Teresa de 《Journal of Electroceramics》2000,4(2-3):369-377
We have studied the pulsed laser deposition (PLD) of Zr1-xCexO2 and Ce1-xLaxO2-x/2 initially to grow buffer layers for perovskite films deposited on Si, LaAlO3, SrTiO3 and MgO and then to produce tunneling barriers for cuprate or manganite heterostructures. On (1 0 0) Si, the deposition of Zr1-xCexO2 (x = 0.12) produces a smooth epitaxial layer (R
RMS = 0.25/1m2), which allows the further deposition of high quality YBa2Cu3O7 (Tc 88 K) and La0.7Sr0.3MnO3 films. On the other hand, the use of Ce1-xLaxO2-x/2 (0 x 0.4) makes it possible to match the YBa2Cu3O7 and La0.7Sr0.3MnO3 layers to various substrates. The buffer layers are epitaxially grown with a 45° rotation of the in-plane axes with respect to those of the substrate, and the smoothness is high (R
RMS = 0.25/1m2). In the case of an ultra-thin barrier (2.5 nm) of Ce1-xLaxO2-x/2 sandwiched in a La0.7Sr0.3MnO3, the out-of-plane mismatch of 2 induces distortions at the interface steps, which propagate into the topmost La0.7Sr0.3MnO3 layer. This is in contrast to the case of SrTiO3 barriers where an ideal crystal continuity in the growth direction is observed. 相似文献
108.
Giovanna Loredana La Torre Marcello SaittaFortunato Vilasi Teresa PellicanòGiacomo Dugo 《Food chemistry》2006
Phenolic compounds in Sicilian wines were directly detected using an HPLC with a PDA detector coupled on-line with a MS system equipped with Electrospray Ionisation (ESI) source operated in the negative-ion mode and a quadrupole mass analyzer. In this work, MS spectra were recorded at different voltage, to obtain structural elucidations in addition to molecular mass informations. The different response of the compounds identified has been also evaluated. MS characteristics of cis- and trans-piceid were determined on the basis of the response obtained with the ESI interface. 相似文献
109.
The purpose of this paper is to investigate the swelling of emulsion liquid membranes using dithio-DEHPA as carrier. The application of interest was the removal of zinc from a synthetic aqueous solution which simulates a zinc plant effluent. The effect of several variables such as the concentration of carrier in the membrane, stirring speed and permeation time on the swelling of the emulsion is reported. Experimental results show that occlusion depends mainly on the amount of carrier in the membrane and can be significant when the concentration of carrier is lower than 6.0%. The interfacial tension analysis confirms that the size of globules is influenced by the concentration of carrier in the membrane. Stirring speed and permeation time are related to the water transport and must be kept at low values. 相似文献
110.
Brigida Fernández de Simón Teresa Hernández Isabel Estrella Carmen Gómez-Cordovés 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,194(4):351-354
Summary Variations in low-molecular-weight phenolic compounds in different parts (must, skin, and seeds) of berries ofV. vinifera, variety Cencibel during ripening were studied using HPLC andTLC. Twenty-five different compounds were identified. The differences were chiefly quantitative, although some quantitative differences were also recorded.
Veränderungen des Phenolgehalts während der Reife der Weintrauben: Polyphenole mit niedrigem Molekulargewicht
Zusammenfassung Die Veränderungen der phenolischen Verbindungen mit niedrigem Molekulargewicht während der Reife in verschiedenen Teilen (Saft, Schale und Samen) der Beeren vonV. vinifera, Varietät Cencibel, wurden mit HPLC- und DS-Chromatographie untersucht. Fünfundzwanzig Verbindungen wurden identifiziert. Die Veränderungen waren hauptsächlich quantitativ; einige qualitative Veränderungen wurden ebenfalls beobachtet.相似文献