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11.
During the ripening of three apricot cultivars (“Keckemetska ruza”, “Madjarska najbolja” and “Velika rana”) grown in two different geographical region of Croatia the changes of polyphenols and carotenoids were determined by using high-performance liquid chromatography (HPLC) with UV–Vis photo diode array detection. The content of individual polyphenols during ripening was quite similar, whereas their amount differed significantly. Immature fruits showed the highest level of polyphenols, which decreased at semi-mature fruits and did not change remarkably in commercial mature fruits. Among polyphenols, flavan-3-ols, chlorogenic acid and quercetin-3-rutinoside were dominant in all ripening stages of all apricot cultivars. The quantity of polyphenols during apricot fruits ripening depended on cultivars, while the region of cultivation did not have remarkable influence on polyphenols amount. During ripening carotenoids increased significantly especially β-carotene which represented 70–85% of the total carotenoid content. Besides β-carotene, in all apricot cultivars γ-carotene was found. α-Carotene, zeaxantin and lutein were found in cv. “Madjarska najbolja” and in cv. “Velika rana” α-carotene and lutein were determined. The region of cultivation and the cultivar were important factors, which influenced the carotenoid amount of apricot fruits, and this content was higher in cultivars grown in Mediterranean region.  相似文献   
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In the present study we determine the optical parameters of thin metal-dielectric films using two different characterization techniques based on nonparametric and multiple oscillator models. We consider four series of thin metal-dielectric films produced under various deposition conditions with different optical properties. We compare characterization results obtained by nonparametric and multiple oscillator techniques and demonstrate that the results are consistent. The consistency of the results proves their reliability.  相似文献   
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Mixture layers of Ge:SiO2 of 40:60 mol% respectively, have been prepared by co-sputtering. The thermally induced change of optical properties of the layers was studied by variable angle spectroscopic ellipsometry. The mixture was modelled as an unknown material with optical constants described by multiple oscillators. The optical parameters determined from ellipsometric measurements can be well correlated with structural changes in the mixture. The results indicate that Ge in the mixture deposited or annealed up to 600 °C is in an amorphous state and it redistributes with increase of temperature, changing refractive index through the layer. The crystallization starts between 600 and 650 °C, at first next to the substrate. Crystallites size grows with temperature. Results were compared with findings of grazing incidence wide angle X-ray scattering measurements and a good agreement was found. Ellipsometry has been shown to be an appropriate non-invasive technique for characterization of this kind of layers.  相似文献   
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This paper presents the results of modeling of an inverted pendulum system driven by a linear pneumatic motor and equipped with relatively low-cost potentiometer-based position measurement system. Based on the nonlinear model of the overall pendulum system, which also includes notable friction effects, a linearized model is derived. The linearized model is used as a basis for the design of state feedback controller based on LQ and LQG optimization procedures. The linear state feedback controllers are augmented by a compensator of nonlinear friction effects whose design is based on the results of experimental identification of an appropriate static friction model. The proposed pendulum controller structures have been verified by means of computer simulations and experimentally on the experimental setup of a pneumatically actuated inverted pendulum.  相似文献   
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Cisplatin (Cis-diamminedichloroplatinum II, CP) is an important chemotherapeutic agent, useful in the treatment of several cancers, but with several side effects such as nephrotoxicity. The present study investigated the possible protective effect of selenium (Se) against CP-induced oxidative stress in the rat kidneys. Male Wistar albino rats were injected with a single dose of cisplatin (7 mg CP/kg b.m., i.p.) and selenium (6 mg Se/kg b.m, as Na(2)SeO(3), i.p.), alone or in combination. The obtained results showed that CP increased lipid peroxidation (LPO) and decreased reduced glutathione (GSH) concentrations, suggesting the CP-induced oxidative stress, while Se treatment reversed this change to control values. Acute intoxication of rats with CP was followed by statistically significant decreased activity of antioxidant defense enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST). Treatment with Se reversed CP-induced alterations of antioxidant defense enzyme activities and significantly prevented the CP-induced kidney damage.  相似文献   
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The HPLC phenolic profiles of 52 selected unifloral honey samples produced in Europe were analysed to detect possible markers for the floral origin of the different honeys. Lime‐tree (five markers), chestnut (five markers), rapeseed (one marker), eucalyptus (six markers) and heather (three markers) honeys had specific markers with characteristic UV spectra. In addition, the flavanone hesperetin was confirmed as a marker for citrus honey, as well as kaempferol for rosemary honey and quercetin for sunflower honey. Abscisic acid, which had been reported to be a possible marker for heather honey, was also detected in rapeseed, lime‐tree and acacia honeys. Ellagic acid in heather honey and the hydroxycinnamates caffeic, p‐coumaric and ferulic acids in chestnut, sunflower, lavender and acacia honeys were also detected. The characteristic propolis‐derived flavonoids pinocembrin, pinobanksin and chrysin were present in most samples in variable amounts. © 2001 Society of Chemical Industry  相似文献   
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Multimedia Tools and Applications - Overlapped fingerprints are often found in latent fingerprints lifted from crime scenes and in live-scan fingerprint images when the surface of fingerprint...  相似文献   
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