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731.
Effect of Hydrothermal Treatment of Rapeseed on Antioxidant Capacity of the Pressed Rapeseed Oil 总被引:1,自引:0,他引:1
Aleksandra Szydłowska-Czerniak György Karlovits Ágnes Sosna-Sárdi Csilla Dianoczki Edward Szłyk 《Journal of the American Oil Chemists' Society》2009,86(8):817-825
Response surface methodology (RSM) was used to evaluate the quantitative effects of two independent variables, rapeseed moisture
content and conditioning temperature, on the antioxidant capacity (AC) and total phenolic (TPC), tocopherol (TTC), and phosphorus
contents (PC) in the pressed rapeseed oils. The mean AC results for the crude rapeseed oils ranged from 199.8 to 947.2 μmolTE/100 g.
TPC and PC in the crude rapeseed oils correlated significantly (P < 0.01) and positively with AC of oils (R
2 = 0.9498 and 0.4396, respectively). The experimental results of AC, TPC, and PC were close to the predicted values calculated
from the polynomial response surface model equations (R
2 = 0.9801, 0.9747 and 0.9165, respectively). The effect of oil processing temperature on AC and TPC was about 1.5 times greater
than the effect of moisture level in rapeseed. 相似文献
732.
Pawe Piszko Marcin Wodarczyk Sonia Zieliska Magorzata Gaziska Przemysaw Pociski Karolina Rudnicka Aleksandra Szwed Agnieszka Krupa Micha Grzymajo Agnieszka Sobczak-Kupiec Dagmara Sota Magdalena Kobielarz Magdalena Wojtkw Konrad Szustakiewicz 《International journal of molecular sciences》2021,22(16)
In this research, we synthesize and characterize poly(glycerol sebacate) pre-polymer (pPGS) (1H NMR, FTiR, GPC, and TGA). Nano-hydroxyapatite (HAp) is synthesized using the wet precipitation method. Next, the materials are used to prepare a PGS-based composite with a 25 wt.% addition of HAp. Microporous composites are formed by means of thermally induced phase separation (TIPS) followed by thermal cross-linking (TCL) and salt leaching (SL). The manufactured microporous materials (PGS and PGS/HAp) are then subjected to imaging by means of SEM and µCT for the porous structure characterization. DSC, TGA, and water contact angle measurements are used for further evaluation of the materials. To assess the cytocompatibility and biological potential of PGS-based composites, preosteoblasts and differentiated hFOB 1.19 osteoblasts are employed as in vitro models. Apart from the cytocompatibility, the scaffolds supported cell adhesion and were readily populated by the hFOB1.19 preosteoblasts. HAp-facilitated scaffolds displayed osteoconductive properties, supporting the terminal differentiation of osteoblasts as indicated by the production of alkaline phosphatase, osteocalcin and osteopontin. Notably, the PGS/HAp scaffolds induced the production of significant amounts of osteoclastogenic cytokines: IL-1β, IL-6 and TNF-α, which induced scaffold remodeling and promoted the reconstruction of bone tissue. Initial biocompatibility tests showed no signs of adverse effects of PGS-based scaffolds toward adult BALB/c mice. 相似文献
733.
Joanna Sikora Aleksandra Karczmarska-Wdzka Joanna Bugieda Przemysaw Sobczak 《International journal of molecular sciences》2021,22(16)
Background. Today there are many devices that can be used to study blood clotting disorders by identifying abnormalities in blood platelets. The Total Thrombus Formation Analysis System is an automated microchip flow chamber system that is used for the quantitative analysis of clot formation under blood flow conditions. For several years, researchers have been using a tool to analyse various clinical situations of patients to identify the properties and biochemical processes occurring within platelets and their microenvironment. Methods. An investigation of recent published literature was conducted based on PRISMA. This review includes 52 science papers directly related to the use of the Total Clot Formation Analysis System in relation to bleeding, surgery, platelet function assessment, anticoagulation monitoring, von Willebrand factor and others. Conclusion. Most available studies indicate that The Total Thrombus Formation Analysis System may be useful in diagnostic issues, with devices used to monitor therapy or as a significant tool for predicting bleeding events. However, T-TAS not that has the potential for diagnostic indications, but allows the direct observation of the flow and the interactions between blood cells, including the intensity and dynamics of clot formation. The device is expected to be of significant value for basic research to observe the interactions and changes within platelets and their microenvironment. 相似文献
734.
Aleksandra Masalska 《Catalysis Today》2001,65(2-4):271-277
The catalytic properties of nickel catalysts (50 wt.% of alumina and 50 wt.% of Ni,H-ZSM-5) were investigated and related to the amount of NiO (0–8 wt.%) and the method of nickel incorporation (8 wt.% NiO). Consideration was also given to the method by which zeolite and alumina were combined. The cracking properties of the catalysts increased when the amount of NiO was raised up to 4 wt.%. To decrease the content of aromatic hydrocarbons in the products it is necessary to raise the amount of NiO to a higher level than 4 wt.%. The catalyst prepared by peptisation of the mixture of zeolite and aluminium hydrogel (with ageing process) displayed reduced activity and stability because of the low susceptibility of NiO to reduction. 相似文献
735.
Aleksandra Perovic 《Journal of Materials Science》1985,20(4):1370-1374
The mechanism of formation of depressions and cavities in the middle of the basal faces of hexagonal plates of poly(ethylene terephthalate) oligomer single crystals upon growth during heat treatment is investigated. It is proposed that this effect is caused by two simultaneously occurring processes: supersaturation inhomogeneity in the centre of the plates and formation of the kinematic (shock) waves at the edges of the plates. 相似文献
736.
Mladenka Pestorić Olivera Šimurina Dubravka Jambrec Miona Belović Aleksandra Mišan 《International Journal of Food Properties》2013,16(12):2699-2712
In this work, a range of model cookies enriched with different quantities of medicinal herbs, applied in two forms (pulverized mixture and extract), were studied to compare and describe relationships between physicochemical and sensory data. Multivariate statistical methods were applied to estimate relationships in the analyzed data. Analysis of variance showed that the majority of analyzed parameters were highly significant in discriminating among the samples (p < 0.05), which supported the usefulness of their application in characterizing the quality profile of enriched cookies. Principal component analysis on physicochemical data revealed that cookies at the same enrichment level showed more similarities. Principal component analysis on sensory data exhibited a larger separation between the samples with increasing enrichment levels, especially in the case of pulverized herbal mixture. According to partial least squares regression, two significant partial least squares components explained 92.7% and predicted 78.0% variation in the data. The most important parameters in discriminating between the cookies enriched with medicinal herbs were lightness, red tonality, and hardness. The selected physicochemical parameters could be used in future studies to evaluate variously enriched cookies by establishing models and investigating the predictability of sensory quality. 相似文献
737.
Aleksandra Hosa Mina EsentiaJamie Stewart Stuart Haszeldine 《Chemical Engineering Research and Design》2011,89(9):1855-1864
Carbon capture, transport and storage (CCS) is a very active field of research, because of its potential to make large reductions of emissions from fossil fuel combustion relevant to climate change. This paper reviews the recent and current work on practical injections of CO2 as research tests for storage projects and specifically focuses on industrial-scale or relevant injections into saline formations (about 1 Mt CO2 per year). All injection projects around the world have been reviewed, and 20 are reported to compile, depth, reservoir quality and injectivity, cost, and rate. This shows that testing of injection is concentrated onshore; however the projects with the highest total CO2 storage estimate are offshore. Pipeline transport systems are mostly used for the large projects. Formations targeted in the injection process are sandstone or carbonate. In the majority of cases initial projections of injectivity are confirmed in tests. A variety of monitoring techniques are used in all projects, these have detected CO2, but have not shown unexpected CO2 movement. Practical experiences of CO2 injection operations therefore suggest that similar operations can be successfully carried out in the saline formations of the UK North Sea and other large sedimentary basins. 相似文献
738.
Contemporary designed and manufactured products should meet a wide range of client requirements and expectations regarding quality for conditions of use in a life cycle. Therefore, design methods, which enable an optimal choice of product parameters by decreasing product sensivity to occurrence of some disturbances in a manufacturing process, become more and more significant in industrial practice. Such a behavior probably allows getting the lowest quality loss while keeping planned production costs. In this article, a new method of products design robust to disturbances exsisting in a technological process is presented. The application of mathematical modeling and methods of parameter estimation enabled formulating an approach in which parameters and acceptable tolerance of manufacturing product parameters are calculated. The efficiency of the proposed method was verified in the machine‐building industry with the example of designing parameters of a brushless direct current motor. © 2010 Wiley Periodicals, Inc. 相似文献
739.
Steve De Backer Aleksandra Piurica Bruno Huysmans Wilfried Philips Paul Scheunders 《Image and vision computing》2008,26(7):1038-1051
In this paper, we study denoising of multicomponent images. The presented procedures are spatial wavelet-based denoising techniques, based on Bayesian least-squares optimization procedures, using prior models for the wavelet coefficients that account for the correlations between the spectral bands. We analyze three mixture priors: Gaussian scale mixture models, Bernoulli-Gaussian mixture models and Laplacian mixture models. These three prior models are studied within the same framework of least-squares optimization. The presented procedures are compared to Gaussian prior model and single-band denoising procedures. We analyze the suppression of non-correlated as well as correlated white Gaussian noise on multispectral and hyperspectral remote sensing data and Rician distributed noise on multiple images of within-modality magnetic resonance data. It is shown that a superior denoising performance is obtained when (a) the interband covariances are fully accounted for and (b) prior models are used that better approximate the marginal distributions of the wavelet coefficients. 相似文献
740.
Silvana?Rossy?de?Brito Aleksandra?do?Socorro da SilvaEmail author Eulália?Carvalho?da?Mata Nandamudi?Lankalapalli?Vijaykumar Cláudio?Alex?Jorge?da?Rocha Maurílio?de?Abreu Monteiro Jo?o?Crisóstomo?Weyl?Albuquerque?Costa Carlos?Renato?Lisboa?Francês 《Information Systems Frontiers》2018,20(4):883-899
Despite advances in the quality and availability of information and communication technologies (ICT), the level of access and skill in using these resources remains unequal. This is particularly evident in developing countries. To reduce the gap between these levels of ICT use, organizations (both public and private) invest in the expansion of infrastructure by providing ICT access and ICT training. In this study, we demonstrate that there is a gap in current approaches to monitor and evaluate large-scale ICT training interventions. Thus, we propose an approach based on social network analysis and data mining techniques, and apply it to an online training program conducted in different regions of Brazil. The results allow us to examine different aspects of the program, such as the region of participants, the institutions driving the intervention, local indicators of telecommunications infrastructure, and local socioeconomic conditions. 相似文献