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951.
Oana Maria Păduraru Diana Ciolacu Raluca Nicoleta Darie Cornelia Vasile 《Materials science & engineering. C, Materials for biological applications》2012,32(8):2508-2515
Novel physically cross-linked cryogels containing polyvinyl alcohol (PVA) and various amounts of microcrystalline cellulose were obtained by freezing/thawing technique. The main goal of this study was to improve the properties and the performances of the pure PVA cryogels. The morphological aspects of the cryogels were studied by scanning electron microscopy (SEM). The Fourier transform infrared spectroscopy (FT-IR) was used to reveal the presence of the interactions between the two polymers. Changes in crystallinity of the samples were confirmed by X-ray diffraction (XRD) and by FT-IR spectroscopy. The modification of the thermal behavior induced by cellulose was studied by thermogravimetry. Rheological analysis revealed higher values of storage modulus (G′) for the cryogels containing higher amounts of cellulose. The degree and rate of swelling were controlled by the presence of the natural polymer in the network. The potential application as bioactive compound carriers was tested, using vanillin as an active agent. 相似文献
952.
953.
Raquel Lucas-González Marika Pellegrini Manuel Viuda-Martos José Ángel Pérez-Álvarez Juana Fernández-López 《International Journal of Food Science & Technology》2019,54(4):1232-1239
Persimmon (Diospyros kaki Thunb.) coproducts are rich in fibre, sugar, minerals and bioactive compounds, make it a good candidate for use in the meat industry. The aim was to evaluate the effect of adding (3% and 6%) two different types of persimmon flour (from cultivars ‘Rojo Brillante’ and ‘Triumph’) on the chemical composition (proximate composition, haeme iron and nitrite residual level), physicochemical properties (pH, water activity and colour), lipid oxidation, emulsion stability, texture and sensory acceptance of pork liver pâté. The addition of persimmon flours decreased residual nitrite levels in pâté to an extent that depended on the concentration and type of flour. Lipid oxidation in pâtés was also reduced by persimmon flour addition, an effect made evident by the increase in pâté redness, which could allow its application as natural antioxidant. In a sensory analysis, all the pâtés with persimmon flour added were better accepted than the control. 相似文献
954.
Electronic identity is getting an increased importance nowadays since relentless digitalization and 24/7 connectivity continue to transform everyday life. To support the recognition of electronic identification cross-border within the European Union, the European Commission (EC) released the eIDAS Regulation, which became effective on September 2018. To put eIDAS in practice, the EC has supported the definition of the technical specification; it provides a sample implementation; and it coordinates the eIDAS Network composed of eIDAS nodes of various countries. Each eIDAS node has a generic part required for the communication with the other nodes, and a specific part that each country has to modify independently according to its legal, operational, and technical requirements. Although this specific part is very important because it affects the node flexibility and the interaction with the other actors at the national level, it is less known in practice. We describe the adaptation of this specific part in Italy to perform authentication and provision of attributes through the STORK and STORK 2.0 infrastructures (the predecessors of eIDAS), based on our experience in the homonym projects. Significant effort is spent currently to build real services exploiting the eIDAS infrastructure, eg, the eID4U project proposes eIDAS node extension with new attributes required by some common academic services, such as student registration at a foreign university. We describe the support for these new attributes in the eIDAS nodes and the modification of the specific part of the Italian eIDAS node to allow attributes retrieval from different authorities. 相似文献
955.
Peter W. Dettmar Diana Gil-Gonzalez Jeanine Fisher Lucy Flint Daniel Rainforth Antonio Moreno-Herrera 《Drug development and industrial pharmacy》2018,44(1):30-39
Objective: Research to measure the chemical characterization of alginate rafts for good raft performance and ascertain how formulation can affect chemical parameters.Significance: A selection of alginate formulations was investigated all claiming to be proficient raft formers with significance between products established and ranked.Methods: Procedures were selected which demonstrated the chemical characterization allowing rafts to effectively impede the reflux into the esophagus or in severe cases to be refluxed preferentially into the esophagus and exert a demulcent effect, with focus of current research on methods which complement previous studies centered on physical properties. The alginate content was analyzed by a newly developed HPLC method. Methods were used to determine the neutralization profile and the acid neutralization within the raft determined along with how raft structure affects neutralization.Results: Alginate content of Gaviscon Double Action (GDA) within the raft was significantly superior (p?.0001) to all competitor products. The two products with the highest raft acid neutralization capacity were GDA and Rennie Duo, the latter product not being a raft former. Raft structure was key and GDA had the right level of porosity to allow for longer duration of neutralization.Conclusion: Alginate formulations require three chemical reactions to take place simultaneously: transformation to alginic acid, sodium carbonate reacting to form carbon dioxide, calcium releasing free calcium ions to bind with alginic acid providing strength to raft formation. GDA was significantly superior (p?<.0001) to all other comparators. 相似文献
956.
957.
Voltammetric e-Tongue Based on a Single Sensor and Variable Selection for the Classification of Teas
Dayvison R. Rodrigues Diana S. M. de Oliveira Marcio J. C. Pontes Sherlan G. Lemos 《Food Analytical Methods》2018,11(7):1958-1968
This work presents a simple and low-cost strategy to obtain voltammetric tongues by using a single voltammetric sensor aided by variable selection techniques. A usual electronic tongue consists of an array of physical sensors followed by data compression before pattern recognition modeling. Alternatively, a single voltammetric sensor can also act as an array of pseudo-sensors—applied potentials in a voltammogram—that can be properly selected to perform a given discrimination. The applicability of this strategy was evaluated in the discrimination of teas. Teas prepared for immediate intake (simulating a home-made tea cup) were analyzed with staircase voltammetry at an epoxy-graphite electrode. Voltammograms were submitted to variable selection previously to linear discriminant analysis (LDA) to identify the applied potentials that improve discrimination of teas according to variety, country of origin, and manufacturer. Successive projections algorithm (SPA), genetic algorithm (GA), and stepwise (SW) formulation were the variable selection techniques evaluated. Best results were achieved with SPA/LDA models, with correct classification rates for the prediction set close to 100%. 相似文献
958.
Arunthavanathan Senthuran Goratti Leonardo Maggi Lorenzo de Pellegrini Francesco Kandeepan Sithamparanathan Reisenfield Sam 《Wireless Networks》2019,25(4):1777-1789
Wireless Networks - Cognitive radio networks are more susceptible to jamming attacks due to the nature of unlicensed users accessing the spectrum by performing dynamic spectrum access. In such a... 相似文献
959.
Although Islamophobia and Antisemitism are two phenomena different in their nature, both represent a form of Otherness that entails a complicated inclusion into multi-ethnic societies of modern Europe and the United States. The purpose of the present study is to show how the research literature has portrayed both phenomena in terms of bibliometric data retrieved from the SCIE Clarivate Analytics database. In addition, we were interested to find out if there is a literature that connects Islamophobia and Antisemitism, its direction and influence. Our findings show that because publications and citations on Islamophobia are relatively new, the research in terms of publications draws the attention of academic society in the direction of research of Antisemitism, but the citations count of the literature on Islamophobia exceeds by far that of the literature on Antisemitism. Moreover, we found that although Antisemitism and Islamophobia are distinct trends, there is an interaction between the literatures that discuss both, and the research that combines the analysis of both phenomena gains more influence than research dedicated to each phenomenon separately. 相似文献
960.
A. S. Shkolnik A. V. Savelyev L. Ya. Karachinsky N. Yu. Gordeev R. P. Seisyan G. G. Zegrya S. Pellegrini G. S. Buller V. P. Evtikhiev 《Semiconductors》2008,42(3):291-297
The results of time-resolved photoluminescence studies of heterostructures containing monolayer arrays of InAs/GaAs quantum dots are presented. A two-component time dependence of intensity of photoluminescence from the ground state of quantum dots, with characteristic times of the slow component up to hundreds of nanoseconds and those of rapid one several nanoseconds, is studied. It is shown that the slow component is determined by the transport of nonequilibrium charge carriers between the quantum dots. At low temperatures, the time of the slow component is determined by tunneling, and at high temperatures by thermal escape of nonequilibrium charge carriers. The ratio of the contributions of tunneling and thermal escape is determined by the degree of isolation of quantum dots. A theoretical model is constructed that describes the effect of the dynamics of carrier transport on the emergence and decay of the slow component of photoluminescence. 相似文献