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1.
Fatty acids, tocopherols, and phenolic compounds biogenesis from two major Spanish olive cultivars (Arbequina and Manzanilla) were analyzed for the function of the thermal regime during the fruit ontogeny in a non‐Mediterranean environment. Bilinear models characterized the dynamics of fatty acid biogenesis. Regressions between the accumulated thermal time (TT) and the levels of both oleic and linoleic acids showed different responses to temperature of each olive cultivar. After reaching similar absolute maximum oleic acid contents at similar TT, the levels of this fatty acid decreased markedly in cv. Arbequina and its final concentration was 10 % lower than that found in cv. Manzanilla. In both cultivars, concentrations of all tocopherol isoforms were negatively associated with the TT accumulated over the entire oil accumulation period. Dynamics of phenolic compounds biogenesis showed no clear tendencies with TT. Nevertheless, and whatever the stage of fruit development, secoiridoids were the major phenolic components. Results suggest greater sensitivity of fatty acid metabolism to temperature in cv. Arbequina. This fact points out the necessity of appropriate evaluation of the ambient thermal characteristics before introducing this cultivar into new growing environments.  相似文献   

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The properties of the air-water state diagram, representing the liquid holdups according to gas velocities, in a 0.075 m diameter column are restated. After measurement of the interfacial areas and mass-transfer coefficients, the part of the diagram corresponding to high gas velocities and low liquid contents (10 < UG < 14 m/s and 0.005 < UL < 0.04 m/s) was chosen for the treatment of polluted gas streams. Under these conditions, it was shown that a “droplet column” is very efficient for the treatment of gases polluted by acid vapors (SO2, HCl) and dust (iron oxide, talc, etc.). The cost of energy appeared more favorable than for classical bubble columns.  相似文献   

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To investigate linguistic and perceptual boundaries within the “blue” region of the color gamut, we analyzed sorting data from speakers of six languages who sorted color stimuli by similarity. Two of these languages, Russian and Italian, are thought to have a separate basic color term and category for “light blue,” distinguishing it from “blue,” and the third was English, which lacks this distinction. There has been less study of the possible basicness of “light blue” terms in the other three languages: Lithuanian and Estonian (both spoken in Baltic states) and Udmurt (a linguistic enclave in North Russia). Sorting data from each sample of speakers were analyzed with principal component analysis and multidimensional scaling, reducing them to a pattern of interstimulus similarities. In addition, color‐naming data were collected for five of the languages and confirmed that sorting responses were not simply a reflection of the words used by subjects to label the stimuli. A “clustering index” was created, quantifying the extent of light/dark blue separation and the strength of any category boundary between them; this was low for English‐language participants but high for Russian and Italian. Udmurt and Lithuanian values were also high, whereas Estonian responses were closer to English. Thus, when clustering of blue stimuli is used as an additional indicator of basicness, the results are compatible with earlier evidence that “light blue” is a separate basic color category in Russian and Italian, and further indicate that light blue terms are basic in Udmurt and Lithuanian, but not Estonian. It may be that “blue” categories are especially susceptible to splitting into two under the influence of linguistic contact. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 362–377, 2017  相似文献   

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Polyacrylamide grafted crosslinked poly (vinyl chloride) beads (PAM‐PVC) were prepared by the surface‐initiated controlled/“living” radical polymerization (SI‐CLRP) methodology from the crosslinked poly(vinyl chloride) beads with surface modification with diethyldithiocarbamyl groups under UV irradiation. The macroiniferter, diethyldithiocarbamyl crosslinked poly(vinyl chloride) beads (DEDTC‐PVC) were prepared by the reaction of the surface C? Cl groups with sodium N,N‐diethyl dithiocarbamate. The “grafting from” polymerization exhibited some “living” polymerization characteristics and the percentage of grafting (PG%) increased linearly with polymerizing time and achieved 47.6% after 6 h UV irradiation. The beaded polymer with polyacrylamide surface was also characterized with Fourier transform infrared (FTIR) and scanning electron microscope (SEM). Its adsorption property for Hg(II) ion was also investigated preliminarily. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:3385–3390, 2006  相似文献   

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A comprehensive mathematical model is developed for “living” free‐radical polymerization carried out in tank reactors and provides a tool for the study of process development and design issues. The model is validated using experimental data for nitroxide‐mediated styrene polymerization and atom transfer radical copolymerization of styrene and n‐butyl acrylate. Simulations show that the presence of reversible capping reactions between growing and dormant polymer chains should boost initiation efficiency when using free nitroxide in conjunction with conventional initiator and also increase the effectiveness of thermal initiation. A study shows the effects of the value of the capping equilibrium constant and capping reaction rate constants for both nitroxide‐mediated styrene polymerization (using alkoxyamine as polymer chain seeds) and atom transfer radical polymerization of n‐butyl acrylate (using methyl 2‐bromopropionate as chain extension seeds). Also the effect of introducing additional conventional initiator into atom transfer radical polymerization of n‐butyl acrylate is studied. It is found that the characteristics of long chain growth are determined by the fast exchange of radicals between growing and dormant polymer chains. Polymerization results in batch, semibatch, and a series of continuous tank reactors are analyzed. The simulations also show that a semibatch reactor is most flexible for the preparation of polymers with controlled architecture. For continuous tank reactors, the residence time distribution has a significant effect on the development of chain architecture. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1630–1662, 2002  相似文献   

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Esparto “Stipa tenacissima” cellulose esters derivatives: HECA‐COO? C4H8? COOC2H5, HECA‐COO? C8H16? COOC2H5, and HECA‐COO? C6H4? COOC2H5 were successfully prepared in Tetrahydrofuran (THF)/triethylamine system with a degree of substitution (DS), respectively, DSAD‐Et=0.32, DSSB‐Et=0.22, and DSTRP‐Et=0.50 using hydroxyethyl cellulose acetate (HECA; DSAC=0.50) as intermediate product, and we avoided the drawbacks of cellulose solubility. The structural modifications were investigated using Fourier transform infrared spectroscopy (FTIR), Proton nuclear magnetic resonance (1H‐NMR), Carbon‐13 nuclear magnetic resonance (13C‐NMR), and Distortionless Enhancement by Polarization Transfer 135° (DEPT‐135). The results from these analyses revealed the presence of the characteristic groups indicating that the grafting reaction was successful. The crystallinity and the structure order changes during the esterification reactions were recorded by X‐ray diffraction (XRD), it is found that the crystallinity degree decrease from 63.1% for Esparto “Stipa tenacissima” cellulose to 27.74% for HECA. The thermal stability of the esterified and unmodified cellulose samples was studied by thermogravimetric analysis (TGA)‐differential thermal analysis (DTA); the modified HECA exhibits a decrease in thermal stability relatively to the unmodified HECA, and this may be related to the groups grafted. The resulted cellulose esters HECA‐Px (x = 1, 2, or 3) were soluble in THF and present an amorphous structure justified by XRD spectra. It was noted by TGA‐DTA analysis that the cellulose esters with low melting range were proved as thermoplastic polymers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

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Complexation of palladium(II) acetate [Pd(OAc)2] or dipotassium tetrachloropalladate [K2PdCl4] to “click” polymers functionalized with phenyl, ferrocenyl and sodium sulfonate groups gave polymeric palladium(II)‐triazolyl complexes that were reduced to “click” polymer‐stabilized palladium nanoparticles (PdNPs). Transmission electron microscopy (TEM) showed that reduction using sodium borohydride (NaBH4) produced PdNPs in the 1–3 nm range of diameters depending on the nature of the functional group, whereas slow reduction using methanol yielded PdNPs in the 22–25 nm range. The most active of these PdNPs (0.01% mol Pd), stabilized by poly(ferrocenyltriazolylmethyl)styrene, catalyzed the hydrogenation of styrene at 25 °C and 1 atm hydrogen, with turnover numbers (TONs) of 200,000. When stabilized by the water‐soluble poly(sodium sulfonate‐triazolylmethyl)styrene, the PdNPs (0.01% mol Pd) catalyze the Suzuki–Miyaura coupling between iodobenzene (PhI) and phenylboronic acid [PhB(OH)2] in water/ethanol (H2O/EtOH) at 25 °C with TONs of 8,200. This high catalytic activity is comparable to that obtained with “click” dendrimer‐stabilized PdNPs under ambient conditions.  相似文献   

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