This study reports the influence of aliphatic-aromatic copolyesters (AAC) on selected polylactide (PLA) properties. Processing, mechanical, and thermal properties were determined. In addition, we examined changes occurring in the surface geometrical structure of sample fractures. It was found that PLA as modified with AAC exhibited enhanced impact strength and melt flow rate, unaffected elongation at break, and reduced tensile strength and elasticity modulus. The results also demonstrate the plasticizing properties of AAC, which improved PLA processing and its thermal stability. We also observed insufficient adhesion at the interface between the two components, as well as heterogeneity of the obtained material. 相似文献
In this study, were compared and characterised some of the physicochemical quality parameters as yield, turbidity and its stability of turbidity, viscosity, colour, dry matter, total soluble solid (TSS), total titratable acidity (TTA), pH parameters of quince juices accessions as well as different 11 cultivars before and after 6 months storage time at 4 and 30 °C. Quince fruits were used for the first time to prepare juices. The effect of different cultivars on juice yield was observed. The content of dry matter, TSS, TTA and turbidity value, stability of turbidity, viscosity, and colour in the analysed juices were depended not only on cultivars but also on storage conditions. Juices analysed were characterised by a significant variation in turbidity value and their stability and by a slight variation in viscosity. This information may be used by the juice industry as a starting point for producers of natural attractive juices from quince fruits. 相似文献
The aim of this study was to describe a phytochemical profile, including phenolic compounds, antioxidant capacity, colour and sensory quality attributes (colour, aroma, consistency, sweetness intensity and desirability) of a sour cherry puree (SCP) supplemented with different natural sweeteners. Supplementation of SCP with the sweeteners only slightly affected polyphenol content, which was by 9% (SCP with steviol glycosides) to 26% (SCP with erythritol) lower than in pure SCP. Furthermore, the products with natural sweeteners were characterised for the lowest antioxidant activity than the SCP sample, especially in SCP with erythritol and xylitol. In addition to having high content of polyphenols and high antioxidant activity, these products were also attractive to consumers, especially when supplemented with xylitol, palm sugar or sucrose, but not with Luo Han Kuo fruit, which was found unacceptable. The results showed that most of the obtained SCPs had very promising and interesting phytochemical properties and sensory profiles. 相似文献
The estimation of the ground temperature profile with respect to the depth and time is the key issue in many engineering applications which use the ground as a source of thermal energy. In the present work, the influence of the model components on the calculated ground temperature distribution has been analysed in order to develop an accurate and robust model for the prediction of the ground temperature profile. The presented mathematical model takes into account all the key phenomena occurring in the soil and on its top surface. The impact of individual model elements on the temperature of the soil has been analysed. It has been found that the simplest models and the most complex model result in a similar temperature variation over the simulation period, but only at a low depth. A detailed analysis shows that a larger depth requires more complex models and the calculation with the use of simple models results in an incorrect temperature and a theoretical COP estimation. 相似文献
The effect of cultivation system on phenolic profile, antioxidant capacity and antiproliferation activity in black and red currants was evaluated. Results from this study showed that Ribes fruit grown in organic system posses significantly higher total phenolics, especially anthocyanins, and antioxidant activity (DPPH and FRAP) than fruit grown in conventional system. Phenolic compounds were systematically identified and characterised by UPLC/MS Q‐TOF. The mean value of total polyphenol content in organically grown currants was similar but statistically higher compared with the conventional cultivation (11831.0 and 1543.0 mg/kg of d.m., respectively). The total values of the anthocyanins in ‘Ben Hope’, ‘Ben Alder’, ‘Titania’ and ‘Rondom’ from organic and conventional farms were 1044.5 vs. 1012.4; 1568.3 vs. 1260.4; 1417.2 vs. 1382.2; and 51.8 vs. 57.9 mg kg?1 of d.m., respectively. Conventionally grown red currant had higher anthocyanin content than organically grown red currant (11.8%) but, however, organic fruits of red currant had 2.7 times higher content of oligomeric procyanidins than fruits coming from conventional cultivation. DPPH radical scavenging activity of currant varied from 28.29 to 37.08 mmol Trolox kg?1 (mean 31.20) for organic fruits and from 12.67 to 31.18 mmol Trolox kg?1 (mean 25.76) for conventional fruits. Moreover, all currants from organic cultivation possess higher ferric reducing capacity than conventionally grown fruits. It appeared that extracts of red Ribes cv. ‘Rondom’ coming from organic cultivation revealed stronger antiproliferative effect in comparison with conventional cultivation. However, a similar profile of activity was observed for ‘Ben Hope’, ‘Ben Alder’ and ‘Titania’ independently of the type of cultivation. These results indicate that the cultivation technique had important effect on the ranking of the cultivar systems. 相似文献
Printed electronics has provided different printing techniques as environmentally friendly and cost-effective manufacturing methods of electronic components. The printed items can be produced on low cost, different types of flexible substrates, even when their surface is corrugated. This opens a new application range of printed electronics and makes them competitive with traditionally manufactured electronics. However, it is necessary to investigate new materials to continue the rapid progress in printed electronics. In our study, the electromechanical properties of polymer nanopastes consisted of carbon nanotubes and graphite platelet nanofibers mixed with a conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) were investigated. Their microstructure and the layer morphology were observed using a scanning electron microscope and an optical microscope. The thickness and average roughness of the layers printed on the foil and paper were determined with a contact profilometer. The mechanical durability of the screen printed layers was verified in a cyclic bending test. The highest mechanical durability was exhibited by the polymer pastes containing carbon nanotubes. 相似文献
The aim of the study was to investigate the satiety levels following the consumption of groats and to analyze the relationships between selected nutrients found in the groats. A total of 54 women were enrolled in a crossover, single-blind study. The participants tested five types of groats (a 240-kcal portion for 180 min). The highest satiety was determined for oat groats and barley groats. The correlation analysis indicated that the satiety of the examined groats was correlated to the highest extent with the content of dietary fiber and hydration degree. Studies showed that the key role in the regulation of satiety could be played by the presence of soluble dietary fiber (SDF). The results of the study indicated that all studied types of groats are a good source of high satiety food. Due to their high satiety value, groats should be used in the prevention and dietary treatment of people with excess body weight. 相似文献
The new κ-(BEDT-TTF)2SbF6 phase was grown by electrodeposition on a Si(0 0 1) electrode. This new phase was characterized by X-ray diffraction (XRD) and electronic conductivity measurements, accompanied by calculations of electronic band structures and Fermi surfaces. Below T = 120 K, a decrease in the electronic conductivity suggests a phase transition, attributed to anion ordering. 相似文献
The objective of the study was to define the primary environmental factors affecting the composition of the macrobenthic community in an abandoned open cast sulphur mine pit lake that had been filled with water from a nearby river. We investigated habitats at various depths and the macrobenthic communities; samples were collected by scuba divers. Although rush and submerged vegetation in the subsaline pit lake was abundant and provided potentially good habitat conditions for mayflies, caddisflies, coleopterans, or damselflies, the native insects were scarce. The taxa do not have many representatives in waters with elevated salinity, so those present in the Machów pit lake were mainly euryhaline species. Chironomids were the most abundant macroinvertebrates in shallower zones, whereas non-native zebra mussels were the quantitatively dominant taxon in deep-water zones. Moreover, these non-native mussels were the dominant biomass of invertebrates at all sites in all seasons. The current composition of the invertebrate assemblage was probably primarily determined by the salinated water, which limited the abundance of native species and gave non-native species an edge.