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Aikaterini Zi 《Materials Characterization》2010,61(2):141-144
High purity copper (99.99%) was severely plastically deformed by miniaturized extrusion preceded ECAP at 200 °C. A partially recrystallized microstructure was detected by TEM observations due to the relative high processing temperature. Isochronal annealing was performed to investigate the material's behavior by measuring the development of Vickers microhardness. As copper is a metal with a relative low stacking fault energy, recovery does not occur readily and only recrystallization takes place. 相似文献
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This paper presents experimental results regarding the impact of adding different tertiary amides of fatty acids to mineral diesel fuel; an assessment of the behaviour of these compounds as possible diesel fuel extenders is also included. Measurements of cetane number, cold flow properties (cloud point, pour point and CFPP), density, kinematic viscosity, flash point and distillation temperatures are reported, while initial experiments concerning the effects on particulate emissions are also described. Most of the examined tertiary fatty amides esters have very good performance and they can be easily prepared from fatty acids (biomass). Such compounds or their blends could be used as mineral diesel fuel or even fatty acid methylesters (FAME, biodiesel) substitutes or extenders. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
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Chrysostomos Avgeros Aikaterini Patsatsi Dimitrios Dimitriadis Andigoni Malousi Triantafyllia Koletsa Despoina Papathemeli Antonia Syrnioti Paraskevi Avgerou Elizabeth Lazaridou Georgios Tzimagiorgis Elisavet Georgiou 《International journal of molecular sciences》2023,24(1)
Diagnosis of Mycosis Fungoides (MF) may be challenging, due to its polymorphic nature. The use of miRNAs as biomarkers to assist in diagnosis has been investigated, mainly in skin lesion biopsies. The purpose of this study is to evaluate the plasma levels of miR-146a and miR-155 in MF patients and to investigate their association with SNPs of their genes. Plasma miRNAs were quantified by RT-qPCR. Genomic DNA was used for SNPs’ genotyping by Sanger sequencing. Plasma levels of miR-146a and miR-155 were significantly higher in patients vs. controls, in early MF patients vs. controls, and in advanced vs. early MF patients. Both miRNAs’ levels were significantly higher in stage IIB vs. early-stage patients. miR-155 plasma levels were significantly higher in patients with skin tumors or erythroderma. CC genotype (rs2910164 C>G) was significantly more frequent in healthy controls and associated with lower MF risk and lower miR-146a levels. The AA genotype (rs767649 T>A) was significantly more frequent in patients and correlated with increased MF risk and increased miR-155 levels. The combination of GG+AA was only detected in patients and was correlated with higher MF susceptibility. Increased mir-146a and mir-155 plasma levels in MF is an important finding to establish putative noninvasive biomarkers. The presence of SNPs is closely associated with miRs’ expression, and possibly with disease susceptibility. 相似文献
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Over the last few years, the concept of online loyalty has been examined extensively in the literature, and it remains a topic of constant inquiry for both academics and marketing managers. The tremendous development of the Internet for both marketing and e-commerce settings, in conjunction with the growing desire of consumers to purchase online, has promoted two main outcomes: (a) increasing numbers of Business-to-Customer companies running businesses online and (b) the development of a variety of different e-loyalty research models. However, current research lacks a systematic review of the literature that provides a general conceptual framework on e-loyalty, which would help managers understand their customers better, take advantage of industry-related factors, and improve their service quality. The present study is an attempt to critically synthesize results from multiple empirical studies on e-loyalty. Our findings illustrate that 62 instruments for measuring e-loyalty–with two or more items—are currently in use, influenced predominantly by Zeithaml et al. (J. Marketing 60(2):31–46, 1996) and Oliver (Satisfaction: a behavioral perspective on the consumer. New York: McGraw Hill, 1997). Additionally, we propose a new general conceptual framework, which leads to e-loyalty dividing antecedents into prepurchase, during-purchase and after-purchase factors, based on the act of purchase. To conclude, a number of managerial implementations are suggested in order to help marketing managers increase their customers’ e-loyalty by making crucial changes in each purchase stage. 相似文献
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Aikaterini G. Mantzila 《Electrochimica acta》2006,51(17):3537-3542
Titanium dioxide films were anodically formed at various potentials up to 65 V in 1 M H2SO4. Oxide films were characterized by performing various techniques, including electrochemical impedance spectroscopy, scanning electron microscopy, Raman spectroscopy, ellipsometry and diffuse reflectance FT-IR spectroscopy. Low voltage anodization (up to 10 V) results to amorphous TiO2, whereas at higher applied potentials (up to 65 V), anatase is the predominant form. Anatase films were further hydroxylated with an acidic agent and the effect of this treatment on the overall impedance of the electrodes was studied with impedance spectroscopy. The potential use of anodic (anatase) Ti/TiO2 electrodes in the development of impedimetric immunosensors is also demonstrated by monitoring the immunoreaction of avidin/anti-avidin with different instrumental approaches based on a FRA analyzer, an LCR-meter and a home-built charge integrator (Multipulser). 相似文献
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Shelf-life extension of refrigerated Mediterranean mullet (Mullus surmuletus) using modified atmosphere packaging 总被引:1,自引:0,他引:1
Pournis N Papavergou A Badeka A Kontominas MG Savvaidis IN 《Journal of food protection》2005,68(10):2201-2207
The present work evaluated the quality and freshness characteristics and the effect of modified atmosphere packaging (MAP) on the shelf-life extension of refrigerated Mediterranean mullet using microbiological, biochemical, and sensory analyses. Fresh open sea red mullet (Mullus surmuletus) were packaged in four different atmospheres: M1, 10%/20%/70% (O2/ CO2/N2); M2, 10%/40%/50% (O2/CO2/N2); M3, 10%/60%/30% (O2/CO2/N2); identical fish samples were packaged in air. All fish were kept under refrigeration (4 +/- 0.5 degrees C) for 14 days. Of the three gas atmospheres, the 10%/40%/50% (M2) and 10%/ 60%/30% (M3) gas mixtures were the most effective for inhibiting growth of aerobic microflora in mullet samples until day 10 of refrigerated storage. H2S-producing bacteria and pseudomonads were part of the mullet microflora and their growth was partly inhibited under MAP conditions. Between these two bacterial groups, H2S-producing bacteria (including Shewanella putrefaciens) were dominant toward the end of the storage period, regardless of the packaging conditions. Brochothrix thermosphacta and lactic acid bacteria were found to be members of the final microbial flora of MAP and air-packaged mullet, whereas the Enterobacteriaceae population was lower than other bacterial groups. Of the chemical freshness indices determined, thiobarbituric acid values were variable in mullet samples irrespective of packaging conditions indicative of no specific oxidative rancidity trend. Based on sensorial data and aerobic plate count, trimethylamine nitrogen and total volatile basic nitrogen limit values in the range of ca. 15 to 23 and 52 to 60 mg N/100 g of fish muscle were obtained, respectively, for mullet packaged under modified atmosphere and air. Sensory analyses (odor and taste attributes) showed that the limit of sensorial acceptability was reached after ca. 6 days for the samples packaged in air, 8 days for the M1 and M3 samples, and after 10 days for the M2 samples. Respective shelf-life extension for fresh whole mullet was ca. 2 days (M1 and M3 gas mixtures), and 4 days (M2 gas mixture). 相似文献
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There has been discussion about the extent to which combined heat and power (CHP) plants with thermal stores are suitable for sustainable energy production. At the moment, in the UK the development of this type of plant is limited. This paper analyses the economics and optimum size of CHP operating with gas engines and thermal stores in British market conditions. This is achieved using energyPRO software. It is shown that, due to the big differences in electricity prices between day and night, the use of thermal stores could be profitable in the UK. The economical size of CHP plant for a district or community heating load of 20,000 MWh per year is found to be a 3 MWe gas engine with a 7.8 MWh thermal store. In this case the analysis reveals that the use of a thermal store more than doubles the return on investments (as measured in net present value) compared with the same size of a plant without a thermal store. It is concluded that thermal stores can improve the overall economics of CHP plants in present British circumstances. 相似文献
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Ioannis S. Boziaris Aikaterini Kordila Christos Neofitou 《International Journal of Food Science & Technology》2011,46(4):887-895
Microbial activity and spoilage of Norway lobster (Nephrops norvegicus) from Greek temperate waters, stored in air at 20, 5 and 0 °C was assessed. Microbial spoilage population, Total Volatile‐Base Nitrogen (TVB‐N), Trimethylamine‐Nitrogen (TMA‐N), pH and organoleptic changes were determined. Shelf‐life of Norway lobster stored at 20, 5 and 0 °C was 24, 72 and 96 h respectively. The product was spoiled due to the development of TVB‐N and melanosis of the carapace, as TVB‐N was apparent from the early stages of storage and correlated very well with microbial growth and shelf‐life. Pseudomonas sp. was the predominant spoilage bacterium. Product rejection coincided with TVB‐N levels of 330–400 mg kg?1 and Pseudomonas sp. population level of about 5 × 105 cfu g?1. Pseudomonas sp. and TVB‐N are presumably the Specific Spoilage Organism and the Chemical Spoilage Index of the product. 相似文献