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11.
Spray drying of a phenolic‐rich membrane filtration fraction of olive mill wastewater: optimisation and dried product quality 下载免费PDF全文
Ivana Sedej Rebecca Milczarek Selina C. Wang Runqi Sheng Roberto de Jesús Avena‐Bustillos Lan Dao Gary Takeoka 《International Journal of Food Science & Technology》2016,51(8):1900-1909
Olive mill wastewater (OMWW) from 3‐ and 2‐phase mills was subjected to a two‐step membrane filtration process. The obtained reverse osmosis retentate (RO‐R) is a phenolic‐rich coproduct stream, and the reverse osmosis permeate is a near‐pure water stream. A pilot‐scale spray dryer was used for the production of RO‐R powder. The optimum temperature/feed pump conditions were obtained for 3‐phase (150°C/4.4 Hz) and for 2‐phase RO‐R (175°C/3.8 Hz). The powders obtained by spray drying under these conditions were analysed for physicochemical properties, including identification and quantification of phenolic compounds. Protocatechuic acid, 3‐hydroxytyrosol, tyrosol, vanillic acid and p‐coumaric acid were quantified in both RO‐R powders, which show the possibility to obtain a phenolic‐rich powder from an OMWW filtration fraction. This will lead towards better usage of by‐products from olive oil production. 相似文献
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Ivana M. Radovic Dusica B. Stojanovic Aleksandar Kojovic Milos Petrovic Petar S. Uskokovic Vesna J. Radojevic 《Polymer-Plastics Technology and Engineering》2017,56(11):1188-1195
The study presents a novel method for protection of the first- and the second-generation Grubbs’ catalyst, by incorporation in poly(styrene) fibers through electrospinning technique. Both catalysts are sensitive to the presence of the amine hardeners in the epoxy-based self-healing composites and require protection from deactivation to retain their ability to promote polymerization reaction of the healing agent. Comparison of healing efficiencies of both catalysts suggested that poly(styrene) fibers offer better protection and dispersion for the first-generation Grubbs’ catalyst, although all the samples exhibited high-healing efficiency. Difference in stereoselectivity between two catalysts was also indicated. 相似文献
14.
This paper describes procedure for estimation of travel time on signalized arterial roads based on multiple data sources with application of dimensionality reduction. Travel time estimation approach incorporates forecast of transportation nodes impendence and travel time on network links. Forecasting period is two hours and the estimation is based on historical data and real time data on traffic conditions. Travel time estimation combines multivariate regression, principal component analysis, KNN (k-nearest neighbours), cross validation and EWMA (exponentially weighted moving average) methods. When comparing estimation methodologies, relevantly better results were achieved by KNN method than with EWMA method. This is true for every time interval considered except for evening time interval when signalized arterial roads were uncongested. 相似文献
15.
Ivana Tomaz Luna Maslov Domagoj Stupić Darko Preiner Danijela Ašperger Jasminka Karoglan Kontić 《分离科学与技术》2016,51(2):255-268
Grape skin contains large amounts of different flavonoids so it can be used for their recovery. Optimization of enzyme-assisted extraction of flavonoids was conducted using oenological enzyme preparations with respect to enzyme dosage, temperature, extraction time, pH, and enzyme preparation. Optimal conditions were obtained using enzyme preparation Lallzyme EX-V, at the temperature of 45°C, time of 3 h, pH 2.0, and enzyme dosage of 10.52 mg/g. The new optimized extraction method is less expensive, simple, accurate, and selective for the recovery of simple flavonoids. It is based on an environmentally-friendly extraction solvent which may provide a valuable alternative to conventional methods. 相似文献
16.
Synthesis of poly(N‐isopropylacrylamide) by distillation precipitation polymerization and quantitative grafting on mesoporous silica 下载免费PDF全文
Sushilkumar A. Jadhav Valentina Brunella Ivana Miletto Gloria Berlier Dominique Scalarone 《应用聚合物科学杂志》2016,133(44)
In this work, syntheses of thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM) with different molecular weights were carried out in ethanol by distillation precipitation polymerization (DPP) technique. The synthesized polymers were fully characterized by attenuated total reflection Fourier‐transform infrared (ATR‐FTIR) spectroscopy, nuclear magnetic resonance spectroscopy, and size exclusion chromatography techniques. The lower critical solution temperatures of the polymers were determined with differential scanning calorimetry. A simple and versatile method for the in situ synthesis and grafting of PNIPAM on mesoporus silica nanoparticles (MSNs) with improved control over quantitative grafting is devised. The PNIPAM grafted MSNs were characterized with ATR‐FTIR, thermogravimetric analysis, transmission electron microscopy, and dynamic light scattering analyses. From the results obtained it is showed that quantitative grafting of PNIPAM on MSNs from 1 to 20% by weight can be tuned by manipulating the in situ DPP reaction conditions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44181. 相似文献
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Inside Cover: Hydrophilic trans‐Cyclooctenylated Noncanonical Amino Acids for Fast Intracellular Protein Labeling (ChemBioChem 16/2016) 下载免费PDF全文
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Shraddha G. Mahamulkar Ivana Císaov Ullrich Jahn 《Advanced Synthesis \u0026amp; Catalysis》2015,357(4):793-799
Alkyldiphenylphosphine oxides typically undergo α‐deprotonation with alkyllithium reagents. Here, the lithiation of differentially branched alkyldiphenylphosphine oxides was investigated and a diverse, but predictable reactivity was found. γ‐Branched derivatives undergo selective directed ortho‐metalation (DoM) using butyllithium and TMEDA as an additive. With decreasing degree of γ‐branching α‐lithiation becomes predominant. The ortho‐phosphinoyllithium intermediates are subject to functionalization and C C bond forming reactions, thus providing a convenient approach to new phosphine oxides and phosphine‐borane complexes, which have a good potential for an approach to new ligands for catalysis.
19.
Concurrent milling of Bi4Ti3O12 was carried out in a planetary ball mill with hardened-steel 13 or 6 mm diameter balls with a goal to investigate how the system responds to the constrains imposed by milling. Milling intensity for various milling parameters was derived from the electrical power measurement. The reverse amorphous ↔ crystalline phase transition induced by milling is governed by impact energy and frequency. Below a certain threshold value of impact energy crystallization does not occur, whereas a higher impact frequency accelerates amorphization. Mechanochemical reactions are predominantly discrete processes, which occur at the moment of impact. 相似文献
20.
Nevena Krkić Branislav Šojić Vera Lazić Ljiljana Petrović Anamarija Mandić Ivana Sedej Vladimir Tomović 《Meat science》2013
The effect of a chitosan coating with added essential oil of oregano (Origanum vulgare) on lipid oxidation of dry fermented sausage (Petrovská klobása) was investigated. Fatty acid profile, aldehyde contents and sensory analysis of odor and flavor were determined after drying and during seven months of storage. 相似文献