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排序方式: 共有1933条查询结果,搜索用时 46 毫秒
101.
Lucía Sánchez-Rodríguez Marina Kranjac Zvonimir Marijanović Igor Jerković David Pérez-López Ángel A. Carbonell-Barrachina Francisca Hernández Esther Sendra 《Journal of the American Oil Chemists' Society》2020,97(5):449-462
Three new regulated deficit irrigation (RDI) treatments were applied to “Arbequina” olive orchards during pit hardening. Oil quality was determined by measuring analytical parameters for olive oil grading, antioxidant activity, total phenol content, fatty acid profile, volatile compounds profile, and sensory analysis. Oils from RDI were classified as “extra virgin olive oil” and their quality was improved due to their higher antioxidant potential (ABTS+ [increased ~75%] and DPPH˙ [increased ~25%] assays) and phenols (increased ~53%) than control. Concentration of total volatile compounds decreased (~27%) but RDI olive oils showed a more balanced profile (alcohols, aldehydes, and esters). Monounsaturated fatty acid content increased (~5%) and atherogenic and thrombogenic indexes decreased (~8.5%) in RDI olive oil. Regarding sensory analysis, RDI provided more balanced oils with higher fruit aroma than control. Other benefits of RDI olive oil, when compared with oil from full irrigated orchards are reduced use of water and improved functional and sensory quality. 相似文献
102.
103.
Marina Villegas Amador C. Caballero Carlos Moure Pedro Durán José F. Fernández Robert E. Newnham 《Journal of the American Ceramic Society》2000,83(1):141-46
Pb(Zn1/3 Nb2/3 )O3 -based ceramics have been prepared by two different processing methods: conventional (PZN-C) and reaction-sintering (PZN-RS). The conventionally prepared PZN-based ceramics densified at lower temperatures (950°C) than the reaction-sintered samples (1100°C), but the perovskite/pyrochlore ratio was always higher in PZN-RS. The presence of a substantial amount of pyrochlore phase in PZN-C ceramics caused a decrease in the electrical properties. The maximum dielectric constant values in PZN-C ceramics were 10%–15% lower than those of PZN-RS, despite a similar average grain size, 7 ± 0.2 μm. The temperature of the maximum of the dielectric constant ( T max ) was lower than that expected from the mixing rule because of the possible formation of Ba–Nb clusters. The higher chemical homogeneity in PZN-RS ceramics is the main reason for the higher dielectric constant, T max and electromechanical response, as well as for the lower difference between T max and the depolarization temperature ( T d ) and the lower diffusiveness parameter (δ). 相似文献
104.
Maarit J. Rein Velimatti Ollilainen Mikko Vahermo Jari Yli-Kauhaluoma Marina Heinonen 《European Food Research and Technology》2005,220(3-4):239-244
In most fruit and berry products the attractive red color is unstable and easily susceptible to degradation. The colors of strawberry and raspberry juices can be enhanced and stabilized by the addition of cinnamic acids. The aim of this study was to identify the novel anthocyanin products responsible for the improved juice color. The pyranoanthocyanins formed were detected using high-performance liquid chromatography, and the fractions from this were analyzed using a nano-ESI tandem MS technique. The pyranoanthocyanins identified were formed from reactions of the main anthocyanins of strawberry and raspberry juices with ferulic acid or sinapic acid. The new anthocyanin derivatives were the 4-vinylguaiacol and 4-vinylsyringol adducts of pelargonidin and cyanidin. This is the first time that pelargonidin 3-glucoside-based vinylphenol pyranoanthocyanins and pyranoanthocyanins with more complex sugar residues have been found. This is also the first time pyranoanthocyanins have been detected in strawberry and raspberry juices. 相似文献
105.
Marina M. Radišić Tatjana M. Vasiljević Nikolina N. Dujaković Mila D. Laušević 《Food Analytical Methods》2013,6(2):648-657
This study presents an application of rapid and sensitive multiresidue method for the analysis of acephate, acetamipride, atrazine, carbendazim, carbaryl, carbofuran, dimethoate, imidacloprid, linuron, malathion, monocrotophos, monuron, propazine, simazine, and tebufenozide in fruits. The method involves an extraction procedure based on matrix solid-phase dispersion using diatomaceous earth as a dispersant and dichloromethane as the eluent. The target pesticides were determined using liquid chromatography–ion trap mass spectrometry. Quantification of the analytes was carried out using the most sensitive ion transition. Ion trap parameters, like activation q and time, were found to have a prominent influence on method sensitivity for some pesticides and they were optimized accordingly. The confirmation of residues detected in real samples was performed by repeated injection and acquiring additional ion transitions besides the ones used for quantification. The method was validated for accuracy, linearity, reproducibility, and sensitivity. Mean values for recoveries were in the range of 70–120 % for all tested matrices. Repeatability of the method, expressed as the relative standard deviation, was in general lower than 20 %. The applicability of the method to routine analysis was tested in real fruit samples with good performance. 相似文献
106.
Marina R. Pascucci 《International Journal of Applied Ceramic Technology》2013,10(5):740-746
The Ceramic Leadership Summit is designed to explore business opportunities, emerging technologies, and critical issues that challenge the ceramic and glass materials community. In 2012, the 3rd Ceramic Leadership Summit was held in conjunction with the 4th International Congress on Ceramics (ICC4). The one‐day program focused on technology transfer, entrepreneurship, and product innovation. Important topics discussed included strategies for creating and sustaining a small business, intellectual property protection, technology transfer, and mechanisms for government–university–industry partnerships. International speakers in the case study session addressed these topics from the perspective of their local and national policies and practices. Several of the case study presentations highlighted the use of “waste materials” in the creation and application of new technologies and products. 相似文献
107.
Bernette M. Oosterlaken Yifei Xu Mark M. J. van Rijt Marina Pilz da Cunha Gilles H. Timmermans Michael G. Debije Heiner Friedrich Albertus P. H. J. Schenning Nico A. J. M. Sommerdijk 《Advanced functional materials》2020,30(6)
In this work, a nanohybrid material based on a freestanding polymeric liquid crystal network capable of postmodification via cation exchange to tune birefringence is proposed. The smectic liquid crystal films can be infiltrated with a variety of cations, thereby changing the refractive indices (ne and no) and the effective birefringence (Δn) of the nanohybrid material, with reversible cation infiltration occurring within minutes. Birefringence could be tuned between values of 0.06 and 0.19, depending on the cation infiltrated into the network. Upon infiltration, a decrease in the smectic layer spacing is found with layer contraction independent of the induced change in birefringence. Potential applications are in the field of specialty optical devices, such as flexible, retunable reflective filters. 相似文献
108.
109.
Tanya L. Poshusta Nagaaki Katoh Morie A. Gertz Angela Dispenzieri Marina Ramirez-Alvarado 《International journal of molecular sciences》2013,14(11):22604-22617
Light chain (AL) amyloidosis is a devastating disease characterized by amyloid deposits formed by immunoglobulin light chains. Current available treatments involve conventional chemotherapy and autologous stem cell transplant. We have recently concluded a phase III trial comparing these two treatments. AL amyloidosis patients who achieve hematological complete response (CR) do not necessarily achieve organ response regardless of the treatment they received. In order to investigate the possible correlation between amyloid formation kinetics and organ response, we selected AL amyloidosis patients from the trial with kidney involvement and CR after treatment. Six patients were selected and their monoclonal immunoglobulin light chains were characterized. The proteins showed differences in their stability and their kinetics of amyloid formation. A correlation was detected at pH 7.4, showing that less stable proteins are more likely to form amyloid fibrils. AL-T03 is too unstable to form amyloid fibrils at pH 7.4. This protein was found in the only patient in the study that had organ response, suggesting that partially folded species are required for amyloid formation to occur in AL amyloidosis. 相似文献
110.
Rosa Iacovino Filomena Rapuano Jolanda Valentina Caso Agostino Russo Margherita Lavorgna Chiara Russo Marina Isidori Luigi Russo Gaetano Malgieri Carla Isernia 《International journal of molecular sciences》2013,14(7):13022-13041
The aptitude of cyclodextrins (CDs) to form host-guest complexes has prompted an increase in the development of new drug formulations. In this study, the inclusion complexes of pipemidic acid (HPPA), a therapeutic agent for urinary tract infections, with native β-CD were prepared in solid state by kneading method and confirmed by FT-IR and 1H NMR. The inclusion complex formation was also characterized in aqueous solution at different pH via UV-Vis titration and phase solubility studies obtaining the stability constant. The 1:1 stoichiometry was established by a Job plot and the inclusion mechanism was clarified using docking experiments. Finally, the antibacterial activity of HPPA and its inclusion complex was tested on P. aeruginosa, E. coli and S. aureus to determine the respective EC50s and EC90s. The results showed that the antibacterial activity of HPPA:β-CD against E. coli and S. aureus is higher than that of HPPA. Furthermore, HPPA and HPPA:β-CD, tested on human hepatoblastoma HepG2 and MCF-7 cell lines by MTT assay, exhibited, for the first time, antitumor activities, and the complex revealed a higher activity than that of HPPA. The use of β-CD allows an increase in the aqueous solubility of the drug, its bioavailability and then its bioactivity. 相似文献