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The cationic ring-opening polymerization of 2-oxazolines in acetonitrile was investigated under pressure conditions utilizing methyl tosylate as initiator of which the single crystal X-ray structure is described as well. The polymerization kinetics were studied and compared with previously reported microwave-assisted pressure polymerizations. Moreover, a series of block copolymers was synthesized in an automated parallel synthesis robot utilizing this pressure polymerization method. The resulting block copolymers were characterized with both differential scanning calorimetry and contact angle measurements to determine the effect of copolymer composition on glass transition temperature, melting point and surface energy. Atomic force microscopy was applied to further investigate the possible phase separation. 相似文献
23.
Color appearance models, among other things, predict the hue of a stimulus when compared with defined stimuli that represent the four unique hues. Recent studies have indicated that the stimuli representing with high reliability unique hue (UH) percepts vary widely for different color‐normal observers. The average yellow and blue UH stimuli for 102 observers, as determined in a recent experiment at medium chroma, differ considerably from the CIECAM02 defined unique hues, based on the Swedish NCS. Wide inter‐observer variability precludes color appearance models from accurately predicting, for individual observers, all four unique hue stimuli. However, models should predict accurately those of a well‐defined average observer. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 505–506, 2008 相似文献
24.
Impact of diet supplemented with microencapsulated condensed tannins on cow milk nutritional profile
Attilio Matera Lucia Sepe Silvia Vincenzetti Roberta Tolve Nicola Condelli Salvatore Claps Francesco Genovese Annamaria Ricciardi Teresa Zotta Teresa Scarpa Maria Antonietta Di Napoli Giulia Francesca Cifuni Paolo Polidori Giuseppe Santini Luciano Scarano Giuseppe Altieri Giovanni Carlo Di Renzo Sofia Renzi Marilisa Giavalisco Fernanda Galgano 《International Journal of Dairy Technology》2023,76(4):813-827
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock. 相似文献
25.
Di Renzo M. Graziosi F. Santucci F. 《Wireless Communications, IEEE Transactions on》2009,8(10):5060-5074
In the present contribution, we propose a comprehensive framework for the analysis of cooperative dual-hop wireless systems over generalized fading channels, which use an amplify and forward (AF) relaying mechanism with blind and semi-blind relays. In particular, the proposed framework provides either exact results or very accurate bounds for computing the moment generating function (MGF) of the end-to-end signal-to-noise ratio (SNR) for various fading channel models typically encountered in real propagation environments. Furthermore, with the help of the MGF-based approach for performance analysis of wireless systems over fading channels, we will show that important performance indexes can be easily derived from the MGF. With respect to previous published articles on the matter, the main contribution of the paper is twofold: i) by relying on the properties of the Meijer-G function, either exact expressions or accurate bounds for the MGF of the end-to-end SNR are provided, and ii) the analysis encompasses the vast majority of fading channel models. Numerical and simulation results will be compared to substantiate the analytical derivation. 相似文献
26.
Calabrese V Bates TE Mancuso C Cornelius C Ventimiglia B Cambria MT Di Renzo L De Lorenzo A Dinkova-Kostova AT 《Molecular nutrition & food research》2008,52(9):1062-1073
Free radicals play a main pathogenic role in several human diseases such as neurodegenerative disorders, diabetes, and cancer. Although there has been progress in treatment of these diseases, the development of important side effects may complicate the therapeutic course. Curcumin, a well known spice commonly used in India to make foods colored and flavored, is also used in traditional medicine to treat mild or moderate human diseases. In the recent years, a growing body of literature has unraveled the antioxidant, anticarcinogenic, and antinfectious activity of curcumin based on the ability of this compound to regulate a number of cellular signal transduction pathways. These promising data obtained in vitro are now being translated to the clinic and more than ten clinical trials are currently ongoing worldwide. This review outlines the biological activities of curcumin and discusses its potential use in the prevention and treatment of human diseases. 相似文献
27.
Infrastructure Deployment in Vehicular Communication Networks Using a Parallel Multiobjective Evolutionary Algorithm 下载免费PDF全文
This article describes the application of a multiobjective evolutionary algorithm for locating roadside infrastructure for vehicular communication networks over realistic urban areas. A multiobjective formulation of the problem is introduced, considering quality‐of‐service and cost objectives. The experimental analysis is performed over a real map of Málaga, using real traffic information and antennas, and scenarios that model different combinations of traffic patterns and applications (text/audio/video) in the communications. The proposed multiobjective evolutionary algorithm computes accurate trade‐off solutions, significantly improving over state‐of‐the‐art algorithms previously applied to the problem. 相似文献
28.
Rouzbeh Ramezani Saeed Mazinani Renzo Di Felice 《Korean Journal of Chemical Engineering》2018,35(10):2065-2077
The performance of potassium carbonate (K2CO3) solution promoted by three amines, potassium alaninate (K-Ala), potassium serinate (K-Ser) and aminoethylethanolamine (AEEA), in terms of heat of absorption, absorption capacity and rate was studied experimentally. The experiments were performed using a batch reactor, and the results were compared to pure monoethanolamine (MEA) and K2CO3 solutions. The heat of absorption of K2CO3+additive solution was calculated using the Gibbs-Helmholtz equation. In addition, a correlation for prediction of CO2 loading was presented. The results indicated that absorption heat, absorption rate and loading capacity of CO2 increase as the concentration of additive increases. The blend solutions have higher CO2 loading capacity and absorption rate when compared to pure K2CO3. The heat of CO2 absorption for K2CO3+additive solutions was found to be lower than that of the pure MEA. Among the additives, AEEA showed the highest CO2 absorption capacity and absorption rate with K2CO3. In conclusion, the K2CO3+AEEA solution with high absorption performance can be a potential solvent to replace the existing amines for CO2 absorption. 相似文献
29.
Retinal blood vessel segmentation using line operators and support vector classification 总被引:1,自引:0,他引:1
In the framework of computer-aided diagnosis of eye diseases, retinal vessel segmentation based on line operators is proposed. A line detector, previously used in mammography, is applied to the green channel of the retinal image. It is based on the evaluation of the average grey level along lines of fixed length passing through the target pixel at different orientations. Two segmentation methods are considered. The first uses the basic line detector whose response is thresholded to obtain unsupervised pixel classification. As a further development, we employ two orthogonal line detectors along with the grey level of the target pixel to construct a feature vector for supervised classification using a support vector machine. The effectiveness of both methods is demonstrated through receiver operating characteristic analysis on two publicly available databases of color fundus images. 相似文献
30.
Structure and functioning of colonial pyrosomes are largely undescribed and their lipid characteristics have received limited attention. The aim of this paper is to fill this gap on one of the dominant species Pyrosoma atlanticum. Lipid content is tightly coupled to size and weight. Lipid composition shows a large dominance of structural polar lipids. Neutral lipids were dominated by sterols with low levels of acylglycerols and free fatty acids. Phospholipids show a dominance of PC with intermediate percentages of PE and DPG. Other constituents (PS, PI, LPC, sphingolipids) were present at lower levels. Fatty acid composition of DAG and TAG showed a dominance of saturated acids (16:0, 14:0), DHA and intermediate levels of MUFA. Phospholipids were dominated by DHA with values exceeding 30% of total FA in all categories except for PI, where lower percentages occurred. Saturated acids were second in abundance with MUFA showing intermediate concentrations. Sterols were dominated by 24-methylcholesta-5,22E-dien-3beta-ol with more than 22% of the total sterol. Cholesterol (cholest-5-en-3beta-ol) represented only 12 % of the total while 24-methylcholesta-5,24(28)E-dien-3beta-ol accounted for 11% of the total sterols. The low levels of triacylglycerols and free fatty acids, coupled with high concentrations of glycolipids and phytoplankton-derived degraded chloropigments, is evidence of a direct link with the digestive activity and substantiate the idea of a high physiological turnover as an alternative to large lipid accumulation. The fatty acid and sterol profiles are consistent with a diverse phytoplankton diet, and a strong contribution of phospholipid classes to energy needs, including locomotion. 相似文献