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191.
Pedreira P Esteban L Criado AR Acedo P Sánchez M Sánchez J 《The Review of scientific instruments》2010,81(10):10D517
A high spatial resolution two color [CO(2), λ=10.6?μm/Nd:YAG (Nd:YAG denotes neodymium-doped yttrium aluminum garnet), and λ=1.064?μm] expanded-beam multichannel heterodyne interferometer has been installed on the TJ-II stellarator. Careful design of the optical system has allowed complete control on the evolution of both Gaussian beams along the interferometer, as well as the evaluation and optimization of the spatial resolution to be expected in the measurements. Five CO(2) (measurement) channels and three Nd:YAG (vibration compensation) channels have been used to illuminate the plasma with a probe beam of 100 mm size. An optimum interpolation method has been applied to recover both interferometric phasefronts prior to mechanical vibration subtraction. The first results of the installed diagnostic are presented in this paper. 相似文献
192.
Raúl F. Guerrero Belén Puertas María I. Fernández Miguel Palma Emma Cantos-Villar 《Innovative Food Science and Emerging Technologies》2010,11(1):231-238
Bioactive products enriched in stilbenes are considered of potential future interest, and the main sources of stilbenes in human diet are grapes. Postharvest ultraviolet C (UV-C) treatment was used to induce stilbene biosynthesis in grapes of three varieties of Vitis vinifera sylvestris, seven of Vitis vinifera sativa, and two Hybrid Direct Producers (HDPs). Stilbenes have been identified by UPLC-DAD-TQD and quantified by HPLC-DAD, and cluster analyses have been performed to classify subspecies by their stilbene profile. After UV-C treatment, the Syrah variety reached a maximum of 25 mg kg? 1 f.w. of total stilbenes in the 2008 vintage, and in the statistical analysis, this variety stood out from the other Vitis varieties tested. In 2008, varieties belonging to the sylvestris group and Vitis vinifera sativa Merlot also presented high stilbene production; however, the expected concentration in the HDPs was not obtained.Industrial relevanceIn this study, postharvest UV-C treatment has been applied to obtain stilbene-enriched grapes from several subspecies of Vitis. The most suitable raw material for bioactive stilbene-enriched products, such as nutraceutics and wines, has been established. This is an essential prerequisite to scaling up the process. Such stilbene-enriched products are known to have added-value as a result of the confirmed positive bioactivity of these compounds, and are gaining market acceptance. 相似文献
193.
The preferential oxidation of carbon monoxide in the presence of hydrogen (PROX reaction) was studied on Cu catalysts promoted with Fe, Nb, Ce, and Ni supported on TiO2 and on TiO2 nanotubes. The surface area of the untreated TiO2 anatase (150 m2/g) support was increase to 350 m2/g when transformed into TiO2 nanotubes (NT). XRD and SEM results confirm the formation of nanotubular structures responsible of the increase in BET surface area. The activity results indicate that a 10% Cu/5% Nb/TiO2-NT catalyst is highly active for this reaction compared to other transition metals and with a catalyst with the same composition supported on untreated TiO2. We found close to 80% CO conversion and 40% selectivity to CO2 formation at 170 °C. The higher activity is ascribed to a higher dispersion of Cu on the TiO2 NT structures. 相似文献
194.
195.
C. Bengoechea A. Romero A. Villanueva G. Moreno M. Alaiz F. Millán A. Guerrero M.C. Puppo 《Food chemistry》2008
This study was focused on the analysis of the chemical composition of defatted carob germ flour and the protein isolate. The amino acid composition and the nature of the subunits that compose carob germ proteins were also studied. Isolate was obtained by alkaline extraction followed by isoelectric precipitation of proteins. Results showed that an isolate of 96.5% of protein content was obtained. A high amount of amino acids like glutamic acid, aspartic acid and arginine was detected. Carob proteins were found to be composed by aggregates formed by a 131 and 70 kDa subunits linked by non-covalent bonds, and other peptides strongly bounded by disulfide interactions. Both, aggregates and subunits were formed mainly by 100 and 48 kDa monomers linked by disulfide bonds. A considerable content of high molecular mass peptides (HMWP) strongly bounded were also found. Proteins became partially denatured and thermally stabilized at acid pH (pH 2). These results could be useful in the study of different functional properties of carob germ proteins, and the application of these proteins as nutritional ingredients in formulated food. 相似文献
196.
Texture changes in dry-cured ham pieces by mild thermal treatments at the end of the drying process 总被引:2,自引:1,他引:1
The present study evaluated the effects of mild thermal treatments at the end of the drying process on physicochemical characteristics and instrumental and sensory texture in dry-cured ham. Experiment 1: effect of thermal treatments (4–46 °C) for 4 h and 24 h. Experiment 2: time effect (4–168 h) of thermal treatments at 30 °C and 36 °C. Both experiments were done on small dry-cured ham dices. Experiment 3: time effect (4–168 h) of thermal treatment at 30 °C on both instrumental and sensory texture of 4-cm-thick sections of dry-cured ham. The thermal treatment at 30 °C for 168 h on both dry-cured ham muscle dices (20 mm × 20 mm × 15 mm) and dry-cured ham sections (4 cm thick) decreased softness, adhesiveness and pastiness in BF muscle, without increasing hardness in SM muscle or affecting moisture, aw and proteolysis index. 相似文献
197.
Briz F. Degner M.W. Guerrero J.M. Diez A.B. 《Industry Applications, IEEE Transactions on》2008,44(3):799-808
Temperature monitoring using the injection of a high-frequency carrier signal voltage is proposed in this paper. The carrier signal voltage is used to estimate the transient impedance of the system, which is a function of the stator transient resistance and, therefore, the windingspsila temperature. The variation of the stator transient impedancepsilas phase angle is used to track the temperature of the stator windings. The method can be implemented in standard inverter-fed drives with no additional hardware, with minimal computational requirements, and with practically no interference with the regular operation of the drive. 相似文献
198.
Lucía Fernández-Espada Carlos Bengoechea José Alberto Sandía Felipe Cordobés Antonio Guerrero 《应用聚合物科学杂志》2019,136(5):47012
The addition of salts, like sodium bicarbonate (SB) or carbonate (SC), into the formulation of bioplastic materials may alter their hydrophilic character to a significant extent. Soy protein isolate (SPI) is a byproduct of the soybean oil industry, which, when properly blended with glycerol (GL), can be further processed through a lab-scale injection molding device. A maximum in the water uptake around 2250 or 2500% is obtained for bioplastics obtained when either SB or SC content is around 1 wt %, respectively. Thus, they exceed the limit to be considered superabsorbent materials (SAMs). Regarding their mechanical properties, a higher presence of SB within the SPI/GL matrix provides materials with a higher extensibility and lower Young's modulus. A higher water uptake is observed after replacing SB for SC in the formulation, probably related to a higher alkalinization of the material as well as to the high hydrophilicity of the carbonate. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47012. 相似文献
199.
Microwave assisted extraction of anthocyanins from grape skins 总被引:1,自引:0,他引:1
A new method for the analysis of anthocyanins in grapes based on a systematic study of the extractability of eleven anthocyanins from grapes has been developed. Microwave assisted extraction was applied as a prior stage to the chromatographic determination of anthocyanins in the extracts. The stability of anthocyanins under the extraction conditions was checked using a standardised extract from grape skins. Temperatures from 50 °C up to 150 °C were evaluated. A fractional factorial experimental design was developed to analyse the influence on the extraction process of six different extraction variables: solvent (mixtures of methanol and water), stirring, extraction temperature, extraction time, microwave power and extraction volume. The extraction solvent was the most important variable for the recovery of most anthocyanins from grapes. Finally, the influence of the extraction time was also studied. With this new method, anthocyanins can be extracted from grapes in 5 min, using 100 °C as extraction temperature and 40% methanol in water as the extraction solvent. Repeatability and reproducibility were also checked, the resulting RSDs (n = 9) were lower than 7% for glucosides, the main components, and lower than 9% for the acyl derivatives, the compounds found in the lowest concentrations. 相似文献
200.
Laura Cuy-Chaparro Michel David Bohrquez Gabriela Arvalo-Pinzn Jeimmy Johana Castaeda-Ramírez Carlos Fernando Surez Laura Pabn Diego Ordez Gina Marcela Gallego-Lpez Carlos Esteban Surez Darwin Andrs Moreno-Prez Manuel Alfonso Patarroyo 《International journal of molecular sciences》2021,22(2)
Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has not been completely defined in Babesia bovis. This study was focused on identifying the minimum B. bovis AMA-1-derived regions governing specific and high-affinity binding to its target cells. Different approaches were used for detecting ama-1 locus genetic variability and natural selection signatures. The binding properties of twelve highly conserved 20-residue-long peptides were evaluated using a sensitive and specific binding assay based on radio-iodination. B. bovis AMA-1 ectodomain structure was modelled and refined using molecular modelling software. NetMHCIIpan software was used for calculating B- and T-cell epitopes. The B. bovis ama-1 gene had regions under functional constraint, having the highest negative selective pressure intensity in the Domain I encoding region. Interestingly, B. bovis AMA-1-DI (100YMQKFDIPRNHGSGIYVDLG119 and 120GYESVGSKSYRMPVGKCPVV139) and DII (302CPMHPVRDAIFGKWSGGSCV321)-derived peptides had high specificity interaction with erythrocytes and bound to a chymotrypsin and neuraminidase-treatment sensitive receptor. DI-derived peptides appear to be exposed on the protein’s surface and contain predicted B- and T-cell epitopes. These findings provide data (for the first-time) concerning B. bovis AMA-1 functional subunits which are important for establishing receptor-ligand interactions which could be used in synthetic vaccine development. 相似文献