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排序方式: 共有210条查询结果,搜索用时 9 毫秒
131.
Suzana I. Dimitrijević Katarina R. Mihajlovski Dušan G. Antonović Mirjana R. Milanović-Stevanović Dušan Ž. Mijin 《Food chemistry》2007,104(2):774-782
Commercial essential oils of Thymus vulgaris L., Rosmarinus officinalis L. and Origanum vulgare L. were chemically characterized by GC, GC/MS analyses. The antilisterial activity of the oils, and the sub-lethal concentration of lactic acid were established by the agar-well diffusion method. The bactericidal kinetics of the diluted oils (50 ppm, 100 ppm, 200 ppm and 300 ppm) and their mixtures with 50 ppm of lactic acid were determined by optical density (OD600) measurements. The results suggest that a sub-lethal dose of lactic acid noticeably increased the antilisterial activity, especially of rosemary and thyme oils, but that the synergistic effects were reduced with higher concentrations of oils. 相似文献
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A new kind of asymmetric organic–inorganic porous structure has been proposed. Asymmetric lattices of polymer grafted silica nanoparticles were manufactured by casting and phase inversion in water. Silica nanoparticles were first functionalized with 3-(dimethylethoxysilyl)propyl-2-bromoisobutyrate, followed by grafting of poly(methylmethacrylate) (PMMA) segments, performed by atom-transfer radical polymerization. Mechanically stable self-standing films were prepared by casting a dispersion of functionalized nanoparticles in different solvents and immersion in water. The resulting asymmetrically porous morphology and nanoparticle assembly was characterized by scanning electron and atomic force microscopy. The PMMA functionalized SiO2 hybrid material in acetone or acetone/dioxane led to the best-assembled structures. Porous asymmetric membranes were prepared by adding free PMMA and PMMA terminated with hydrophilic hydroxyl group. Nitrogen flow of 2800 L m?2 h?1 was measured at 1.3 bar demonstrating the porosity and potential application for membrane technology. 相似文献
134.
Evaluation of catalytic activity of two functionalized imidazolium ionic liquids for biodiesel fuel production by a two‐stage process 下载免费PDF全文
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136.
Renata Pavli
Suzana Vidic Maja Anko Tamara Knific Toma Büdefeld Kristina Marton Maa Sinreih Stefan Poschner Walter Jger Snjeana Frkovi-Grazio Tea Laninik Riner 《International journal of molecular sciences》2021,22(8)
Endometrial cancer (EC) is associated with increased estrogen actions. Locally, estrogens can be formed from estrone-sulphate (E1-S) after cellular uptake by organic anion-transporting polypeptides (OATP) or organic anion transporters (OAT). Efflux of E1-S is enabled by ATP Binding Cassette transporters (ABC) and organic solute transporter (OST)αβ. Currently, 19 E1-S transporters are known but their roles in EC are not yet understood. Here, we analysed levels of E1-S transporters in Ishikawa (premenopausal EC), HEC-1-A (postmenopausal EC), HIEEC (control) cell lines, in EC tissue, examined metabolism of steroid precursor E1-S, studied effects of OATPs’ inhibition and gene-silencing on E1-S uptake, and assessed associations between transporters and histopathological data. Results revealed enhanced E1-S metabolism in HEC-1-A versus Ishikawa which could be explained by higher levels of OATPs in HEC-1-A versus Ishikawa, especially 6.3-fold up-regulation of OATP1B3 (SLCO1B3), as also confirmed by immunocytochemical staining and gene silencing studies, lower ABCG2 expression and higher levels of sulfatase (STS). In EC versus adjacent control tissue the highest differences were seen for ABCG2 and SLC51B (OSTβ) which were 3.0-fold and 2.1-fold down-regulated, respectively. Immunohistochemistry confirmed lower levels of these two transporters in EC versus adjacent control tissue. Further analysis of histopathological data indicated that SLCO1B3 might be important for uptake of E1-S in tumours without lymphovascular invasion where it was 15.6-fold up-regulated as compared to adjacent control tissue. Our results clearly indicate the importance of E1-S transporters in EC pathophysiology and provide a base for further studies towards development of targeted treatment. 相似文献
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Lai Fatt Chuah Jiří Jaromír Klemeš Suzana Yusup Awais Bokhari Majid Majeed Akbar 《Clean Technologies and Environmental Policy》2017,19(3):859-868
Physiochemical properties of biodiesel, a sustainable and green alternative fuel produced from renewable resources, are greatly influenced by the structural features of polyunsaturated, monounsaturated and saturated fatty acids. Two feedstock oils, potentially contribution to cleaner technologies, refined cooking oil and waste cooking oil derived from palm olein have been studied. Fatty acid compositions of the refined cooking oil and waste cooking oil were analysed and confronted with other literature sources. Critical parameters such as cetane number (CN), iodine value, cold filter plugging point (CFPP) and oxidation stability (OS) were correlated with long-chain saturated factor and degree of unsaturation (DU) of fatty acid to match the international standards of cleaner biodiesel. OS in biodiesel has been met with the absence of linolenic acid. High saturated fatty acid provides high CN. The iodine value of feedstock oil met the European standard where the DU of the oils was less than 138. However, CFPP of refined cooking oil and waste cooking oil did not meet the demanding Spanish regional (RD 61/2006) standard due to the presence of stearic and palmitic acid, which tended to clog the fuel filter by precipitating while the biodiesel becomes cool. With the proposed triangular chart for biodiesel properties prediction, potential biodiesel fuels from various feedstock oils can be analysed. 相似文献
139.
Márcio de Almeida D’Agosto Suzana Kahn Ribeiro 《Renewable & Sustainable Energy Reviews》2009,13(6-7):1326-1337
This article uses a first approach LCI procedure to evaluate total and renewable energy and CO2 emissions in Brazilian automotive fuels life cycle (LC). The LC model is structured and modular, capable of being successively refined if necessary. The procedure is applied to passenger car use in urban traffic, comparing three fuels used in Brazil (gasoline with 25% ethanol, pure ethanol and compressed natural gas), considering their use in urban traffic in the city of Rio de Janeiro. An in deep research was made to collect representative and unpublished data of Brazilian automotive fuels LC reality, what is considered a main contribution. The results show where specific advantages occur, particularly in the use of renewable fuels made from biomass, an option already practiced and appropriate for Brazilian reality. The use of gasoline with 25% ethanol shows the lowest total energy consumption for the LC, with similar performance to that of compressed natural gas and 36% better than ethanol from sugarcane. However, the last alternative has the advantage of depending almost exclusively on renewable energy (93%) and producing less net CO2 emissions. 相似文献
140.
Rapid advances in computer and geospatial technology have made it increasingly possible to design and develop urban models to efficiently simulate spatial growth patterns. An approach commonly used in geography and urban growth modelling is based on cellular automata theory and the GIS framework. However, the behaviour of cellular automaton (CA) models is affected by uncertainties arising from the interaction between model elements, structures, and the quality of data sources used as model input. The uncertainty of CA models has not been sufficiently addressed in the research literature. The objective of this study is to analyze the behaviour of a GIS-based CA urban growth model using sensitivity analysis (SA). The proposed SA approach has both qualitative and quantitative components. These components were operationalized using the cross-tabulation map, KAPPA index with coincidence matrices, and spatial metrics. The research focus was on the impacts of CA neighbourhood size and type on the model outcomes. A total of 432 simulations were generated and the results suggest that CA neighbourhood size and type configurations have a significant influence on the CA model output. This study provides insights about the limitations of CA model behaviour and contributes to enhancing existing spatial urban growth modelling procedures. 相似文献