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821.
Niamh Harbourne Eunice Marete Jean Christophe Jacquier Dolores O'Riordan 《Food research international (Ottawa, Ont.)》2013,50(2):480-486
Recently phytochemical constituents have attracted a lot of interest as sources of functional ingredients in food product formulations. However, before being incorporated into foods or beverages the stability of these bioactive constituents during post-harvest preservation procedures, in food matrices and during processing and storage must be considered. This review will focus on the stability of phytochemical constituents of herbs with anti-inflammatory properties, including chamomile, meadowsweet, feverfew and willow. These herbs contain a relatively high content of phenolic compounds in comparison to common fruits and vegetables. They have been traditionally used to make teas or infusions that are consumed as a remedy for pain and inflammation. Effects of preservation and extraction conditions on the level of bioactive constituents will be reviewed. The storage conditions (temperature) and thermal processing at pH levels encountered in food products will also be examined. 相似文献
822.
In this study, the temperature dependence of effective thermal conductivity (ETC) for samples of binary, ternary, and quadruple glass wools reinforced with aluminium foil was examined. The experiments were realized by the guarded hot plate in temperature differences of 5, 10 and 15 °C and the temperatures of 25 and 40 °C. The results revealed that in the case of reinforcing the aluminium foil, ETC increased with increasing the temperature or changing of temperature difference (5, and 15 °C). Also, an increase of additional layers decrease its' influence on low temperature. Consequently, reflectivity materials may increase or reduce ETC. 相似文献
823.
Emilia PǎunescuLudivine Louise Ludovic Jean Anthony Romieu Pierre-Yves Renard 《Dyes and Pigments》2011,91(3):427-434
A versatile methodology for the synthesis of 6/8-halogenated 7-aminocoumarins from the corresponding 7-hydroxy analogs using Pd-catalyzed amination reaction as the key step is presented. Further readily conversion into 7-azidocoumarins was performed and the resulting aryl azides proved higher stability and reactivity than the corresponding non-halogenated parent compound. These new compounds may thus constitute attractive scaffolds for designing novel photoaffinity reagents for various challenging bio-labeling applications. 相似文献
824.
G. Scholz E. Nothnick G. Avramidis A. Krause H. Militz W. Viöl A. Wolkenhauer 《Holz als Roh- und Werkstoff》2010,68(3):315-321
Beech wood was impregnated with two hot melting waxes. Contact angle measurement followed to determine hydrophobizing of such treated wood. Tensile shear tests were carried out to test the adhesion properties with three different glues under varying environmental conditions. Furthermore, wax impregnated beech was subjected to plasma treatment prior to glueing. The results demonstrate that wood treated with polar paraffin shows lower adhesion properties compared to montan wax. Therefore, montan wax was investigated more intensely. Beech impregnated with such wax can be used for constructive building elements in the interior sector. D3 Glues for non-constructive applications were realized by using PVAc and phenol-resorcinol resin under permanent influence of humidity. Plasma treatment improves this quality to obtain D4 glue. Back-drying of the water stored specimens proves the suitability of isocyanate glue and also that of PVAc after plasma treatment for 120 s. 相似文献
825.
Pronk Tila M.; Karremans Johan C.; Wigboldus Dani?l H. J. 《Canadian Metallurgical Quarterly》2011,100(5):827
In the present research, we examined why some people have more difficulty than others in staying faithful to their romantic partners. Three studies supported our main prediction that executive control is associated with romantically involved individuals' ability to stay faithful. Study 1 showed that participants with a higher level of executive control reported less difficulty in staying faithful to their partners than did those with lower levels of executive control. In Study 2, romantically involved male participants were placed in a waiting room together with an attractive female confederate. Results showed that participants with a higher level of executive control showed less flirting behavior with the confederate than did those with lower levels of executive control. Study 3 demonstrated that a higher level of executive control was related to a lower expressed desire to meet an attractive other, but only for romantically involved participants. Together, these studies showed that executive control helps romantically involved individuals to deal with the lure of attractive alternatives. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
826.
No authorship indicated 《Canadian Metallurgical Quarterly》2010,65(8):689
This issue announces the 2010 award winners from the American Psychological Association. In accordance with established custom, the APA bestows annual awards in recognition of outstanding contributions by psychologists across an array of domains. The awards laud distinguished contributions to the advancement of science, to applications of psychological knowledge to clinical and social issues, to education and training, and to work devoted to international cooperation and humanitarian ideals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
827.
The air and oxy-fuel combustion processes of two low-grade lignite coals were investigated by thermogravimetric analysis (TGA) method. Coals were provided from two different coal mines in the Aegean region of Turkey. Oxy-fuel combustion experiments were carried out with three different gas mixtures of 21% O2–79% CO2; 40% O2–60% CO2 and 50% O2–50% CO2 at 950 °C and heating rates of 10 °C/min, 20 °C/min and 40 °C/min. The kinetics of the oxy-fuel combustion of coals were studied by using four different methods namely, Coats-Redfern (model-fitting method), Friedman (FR), Flynn–Wall–Ozawa's (FWO) and Kissinger–Akahira–Sunose's (KAS) methods. The apparent activation energies of combustion process calculated by FWO method are slightly but systematically higher than that calculated by the KAS and FR methods for the oxy-fuel atmospheres. Combustion behavior of both coals in the oxy-fuel combustion environment could vary significantly, likely due to their characteristics such ash and volatile matter contents. 相似文献
828.
No authorship indicated 《Canadian Metallurgical Quarterly》2010,65(8):690a
The American Psychological Association 2010 Awards for Distinguished Scientific Contributions are presented to persons who, in the opinion of the Committee on Scientific Awards, have made distinguished theoretical or empirical contributions to basic research in psychology. The 2010 winners are Jonathan D. Cohen, Susan T. Fiske, and Joseph E. LeDoux. The Award for Distinguished Scientific Applications of Psychology is presented to a person who, in the opinion of the Committee on Scientific Awards, has made distinguished theoretical or empirical advances leading to the understanding or amelioration of important practical problems. The winner for 2010 is David M. Clark. The Awards for Distinguished Scientific Early Career Contributions to Psychology recognize the large number of excellent young psychologists. The 2010 winners are Stanley B. Floresco, Peter J. Gianaros, Mara Mather, Simona Ghetti, Larissa K. Samuelson, Benjamin L. Hankin, and Matthew K. Nock. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
829.
Rafael Salles Kurusu Nicole Raymonde Demarquette Catherine Gauthier Jean‐Marc Chenal 《Polymer International》2014,63(6):1085-1093
Poly(3‐hydroxybutyrate) (PHB) undergoes an ageing process that contributes to its remarkable fragility. Blending it with an elastomer is a possibility to increase toughness. In this work, the mechanical properties of a 70/30 wt% blend of PHB and poly(ethylene‐co‐methyl‐acrylate‐co‐glycidyl‐methacrylate) were studied over time. The phenomenon of ageing affected the blend, which lost its ductility and became fragile days after its processing. Differential scanning calorimetry and small angle X‐ray scattering analyses showed that this drop in mechanical properties was due to changes in the crystalline structure of the matrix. Annealing reduced fragility, increased toughness and prevented a re‐ageing of the blend. Biodegradation in soil was also more intense for annealed samples. © 2013 Society of Chemical Industry 相似文献
830.
Tiina Reponen Klaus Willeke Vidmantas Ulevicius Sergey A. Grinshpun Jean Donnelly 《Aerosol science and technology》2013,47(3):405-421
ABSTRACT Many commercially available devices initially developed for dispersion of biologically inert particles have been adopted for aerosolization of microoganisms in laboratory settings. However, these dispersion devices are not always adequate for microbial particles, as they do not simulate natural release into air. Wet dispersion methods are appropriate for viruses and most bacteria, whereas dry methods are more suitable for most fungal and actinomycete spores. Characteristics of the resulting aerosol are dependent on the dispersing shear forces and the sensitivity and agglomeration of the tested microorganisms. Consequently, each microbial group may need a specific dispersion technique. The following devices have been developed and tested in this study: the bubbling aerosol disperser, the agar-tube disperser, and the swirling-flow disperser. Testing included the evaluation of both physical and microbiological characteristics of aerosolized microorganisms. Each of the dispersers has shown several advantages over commercially available ones. When used for the dispersion of bacteria from the liquid suspension, the bubbling aerosol disperser was found to produce considerably fewer amounts of microbial fragments and much lower levels of microbial metabolic injury than the commercially available Collison nebulizer. Fungal spores dispersed from their colonies by the agar-tube disperser were found to have a more stable aerosol concentration and a lower fraction of agglomerates than achievable by conventional powder dispersion. The swirling-flow dispersion technique was used for aerosolization of actinomycetes because the agar-tube disperser could not provide a stable concentration of these spores due to their smaller size. The tests have shown that new methods minimize the changes of properties of the microorganisms during their aerosolization in the laboratory. 相似文献