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51.
The effects of extraction parameters on bioactive compound contents of winemaking waste extracts (WWE) and its effect on rapeseed oil oxidative stability were evaluated. Research showed that the total phenols and anthocyanin contents and antioxidant activity (AA) of WWE significantly depended on the extraction parameters. Increasing the temperature (60 °C) and time (5 h) of extraction and an addition of water to ethanol statistically improved the rate of active component extraction. HPLC analysis showed that procyanidin B2, catechin, gallic acid, γ‐resorcylic acid and p‐coumaric acid were the major phenolic compounds of WWE. Important correlations between total phenolic compounds quantified by HPLC and both DPPH and (ferric reducing antioxidant power) (FRAP) values were found. WWE added to the oil at three different levels clearly slowed down the process of fatty acid oxidation, inhibiting hydroperoxide formation by about 86%, comparable with BHT, while it was more effective than that of α‐tocopherol. When using volatile compound formation as a marker of lipid oxidation, WWE at the level of 2000 ppm were the most effective inhibitors of the decomposition of hydroperoxides. The research showed that the WWE are a rich source of phenolic compounds with powerful antioxidant activities and are suitable for preventing rapeseed oil oxidation.  相似文献   
52.
This study aims at obtaining cross‐linked polymeric materials of biomass origin. For this purpose, one‐pot polyesterification of methyl ricinoleate and methyl 12‐hydroxystearate using titanium isopropoxide as a catalyst is performed leading to polyesters known as estolides. The obtained estolides are successfully cross‐linked using dicumyl peroxide or a sulfur vulcanization system. The so‐formed bio‐based elastomers appear to exhibit promising properties. The latter are analyzed by mechanical tensile tests and thermal techniques (TGA, DSC, DMA) and show high thermal stability (T5% = 205–318 °C), tailored physico‐mechanical properties (low glass transition temperature in the range from ?69 to ?54 °C), and good tensile strength (0.11–0.40 MPa). Networks prepared from high molecular weight estolides appear to be promising bio‐based elastomers. Practical Applications: The vegetable oil‐based estolides described in this contribution are new fully bio‐based precursors for further elastomers synthesis. The resulting estolide networks (obtained by peroxide or sulfur cross‐linking) exhibit tailored thermo‐mechanical properties.  相似文献   
53.
The blends based on poly(lactic acid), (PLA) and polyacrylates (1:1 weight ratio) have been prepared by photopolymerization of three different multifunctional acrylate monomers (pentaerythritol triacrylate, pentaerythritol tetraacrylate and dipentaerythritol pentaacrylate) in matrix of linear PLA. The structure of these systems has been studied by Atomic Force Microscopy (AFM), Differential Scanning Calorimetry (DSC) and X-ray Diffraction (XRD). It was found that the blends are highly crosslinked, rough, heterogeneous and some of them – semicrystalline. The effect of UV-irradiation on surface morphology of obtained mixtures was studied. The viscometry has been applied for measurements of changes of PLA molecular weight resulting of photodegradation. It was shown that blends are much more photostable than pure PLA.  相似文献   
54.
We present electrochemical and spectral properties of symmetric monomers 1,3,5-tris(aryl)benzenes and 2,4,6-tris(aryl)-1-phenols and their polymers. These compounds contain thienyl, furyl or EDOT moieties attached to central benzene or phenol ring at the meta-position, synthesized by a Stille cross-coupling procedure. All monomers are electroactive and undergo electropolymerization creating thin films on an electrode surface. Polymers with meta-linkages were obtained by electrochemical oxidation. Detailed cyclic voltammetry and in situ UV-vis spectroelectrochemistry show that polymers with hydroxy groups exhibit higher conductivity and better stability than with benzene core. Interesting and different behavior occurs for 2,4,6-tris(2-thienyl)-1-phenol, for which the characteristic, sharp, redox peak is observed.  相似文献   
55.
柏木条经过热蒸气处理,成功地制备了纳米孔炭,无需另行活化,比表面积就可达1000m^2/g以上。如果在800℃~870℃炭化,柏木炭外表面积可达400m^2/g以上,与同样温度在氩气中炭化得到的柏木炭相比,后者微孔面积仅为30m^2/g~40m^2/g。在900℃以上炭化得到的柏木炭,微孔表面积高达800m^2/g以上,外表面积约为150m^2/g。柏木炭的孔结构可以通过调节过热蒸气的温度得到控制。  相似文献   
56.
A total of 721 consumers were interviewed in order to obtain and compare consumer-driven associations to the word “Traditional”, in a food context, in six European regions. Participants, who were individually interviewed, had to state the first words that came into their mind when the word “Traditional” was verbally presented. Frequencies of occurrence of associations were obtained and analysed by means of simple correspondence analysis. The different word associations obtained were classified in 55 classes and then grouped in ten principal dimensions by triangulation. In general, southern European regions tended to associate the concept of “Traditional” more frequently with broad concepts such as heritage, culture or history. Central and Nordic European regions tended to focus mainly on practical issues such as convenience, health or appropriateness. As a final outcome of the analyses, a consensus conceptual map of traditional food products was obtained. The empirical findings of this qualitative exploratory free word association test provide valuable insights for product positioning, innovation and new developments in the traditional food market.  相似文献   
57.
The profiling of allergic responses is a powerful tool in biomedical research and in judging therapeutic outcome in patients suffering from allergy. Novel insights into the signaling cascades and easier readouts can be achieved by shifting activation studies of bulk immune cells to the single cell level on patterned surfaces. The functionality of dinitrophenol (DNP) as a hapten in the induction of allergic reactions has allowed the activation process of single mast cells seeded on patterned surfaces to be studied following treatment with allergen specific Immunoglobulin E antibodies. Here, a click‐chemistry approach is applied in combination with polymer pen lithography (PPL) to pattern DNP‐azide on alkyne‐terminated surfaces to generate arrays of allergen. The large area functionalization offered by PPL allows an easy incorporation of such arrays into microfluidic chips. In such a setup, easy handling of cell suspension, incubation process, and read‐out by fluorescence microscopy will allow immune cell activation screening to be easily adapted for diagnostics and biomedical research.  相似文献   
58.
59.
Objective: The article contains results of the experimental studies on atomization process of inhaled drugs and aqueous solutions of glycerol with aqueous solutions of glycerol polyacrylamide (Rokrysol WF1) in pneumatic nebulizers. In experiments, the different concentration of aqueous solutions of glycerol polyacrylamide have been tested. In addition, the effect of nebulizer design on atomization process has been determined. The one of the main elements of medical pneumatic nebulizer is nebulizer cup.

Significance: The experiment with this scope is new and is very important from the point of view of aerosol therapy.

Methods: The results have been obtained by the use of the digital microphotography technique. In order to determine a physicochemical properties of tested liquids, a rheological measurements and measurements of the surface tension were carried out.

Results: The differences between characteristics of aerosol for the liquids have been observed. The analysis of the droplets size distributions shows that the different diameters of droplets for Newtonian and non-Newtonian fluids have been formed during atomization in pneumatic nebulizers equipped with different nebulizer cups. The effect of the mouthpiece location on the droplets diameters has been shown.

Conclusions: Precise design of nebulizer and nebulizer cups, and also physicochemical properties of atomized liquids are of high importance in order to the effectiveness of drug delivery to patient’s respiratory tracts.  相似文献   

60.
As part of this research, the kinetics of soap grease thickener microstructure regeneration during 24-h relaxation after 1-h shearing were studied. A lubricating grease, based on mineral oil ORLEN OIL SN-400, containing associated molecules of lithium 12-hydroxystearate was subjected to analysis. Rheological dynamic oscillatory and FTIR–ATR (Fourier Transform Infrared Attenuated Total Reflectance) spectroscopy were used to study the kinetics of thickener microstructure regeneration. Changes in the values of storage modulus G′ and loss modulus G″ of the investigated grease during its relaxation in the linear viscoelastic range were examined. In addition, the mechanical stability of the thickener microstructure at a variable oscillation frequency was tested, and changes in the cohesive energy of the grease versus the latter’s relaxation time were assessed. FTIR–ATR spectroscopy was used to study the physicochemical interactions between the associated molecules of lithium 12-hydroxystearate. Infrared bands were assigned to the vibrations of the particular functional groups of the grease components, and the spectral parameters in the absorption spectra in the range of 700–3,700 cm?1 were examined. The studies carried out using the two investigative methods have revealed that the intensity of thickener microstructure regeneration was the highest in the first hour of grease relaxation after shearing. In this time interval, the largest changes in the vibrations of the main functional groups of the grease components were observed. In the next hours, the kinetics of thickener microstructure regeneration were substantially lower.  相似文献   
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