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51.
Bulletin of Engineering Geology and the Environment - The alkali silica reaction (ASR), which originates in highly alkaline conditions in concrete where reactive forms of silica are available,...  相似文献   
52.
Nowadays, regenerative medicine faces a major challenge in providing new, functional materials that will meet the characteristics desired to replenish and grow new tissue. Therefore, this study presents new ceramic-polymer composites in which the matrix consists of tricalcium phosphates covered with blends containing a chemically bounded diclofenac with the biocompatible polymer—poly(3-hydroxyoctanoate), P(3HO). Modification of P(3HO) oligomers was confirmed by NMR, IR and XPS. Moreover, obtained oligomers and their blends were subjected to an in-depth characterisation using GPC, TGA, DSC and AFM. Furthermore, we demonstrate that the hydrophobicity and surface free energy values of blends decreased with the amount of diclofenac modified oligomers. Subsequently, the designed composites were used as a substrate for growth of the pre-osteoblast cell line (MC3T3-E1). An in vitro biocompatibility study showed that the composite with the lowest concentration of the proposed drug is within the range assumed to be non-toxic (viability above 70%). Cell proliferation was visualised using the SEM method, whereas the observation of cell penetration into the scaffold was carried out by confocal microscopy. Thus, it can be an ideal new functional bone tissue substitute, allowing not only the regeneration and restoration of the defect but also inhibiting the development of chronic inflammation.  相似文献   
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Twenty three different wild blackberry fruit samples were assessed regarding their phenolic profiles and contents (by LC/MS quadrupole time-of-flight (QTOF) and antioxidant activity (ferric reducing ability of plasma (FRAP) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS)) by two different extraction methods. Thirty four phenolic compounds were detected (8 anthocyanins, 15 flavonols, 3 hydroxycinnamic acids, 6 ellagic acid derivatives and 2 flavones). In samples, where pressurized liquid extraction (PLE) was used for extraction, a greater increase in yields of phenolic compounds was observed, especially in ellagic acid derivatives (max. 59%), flavonols (max. 44%) and anthocyanins (max. 29%), than after extraction by the ultrasonic technique extraction (UAE) method. The content of phenolic compounds was significantly correlated with the antioxidant activity of the analyzed samples. Principal component analysis (PCA) revealed that the PLE method was more suitable for the quantitative extraction of flavonols, while the UAE method was for hydroxycinnamic acids.  相似文献   
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ABSTRACT

Energy poverty is generally caused by having a low income, facing high energy costs, and living in a home with low energy efficiency. Various indicators capture these facets, but there is no consensus which is the best one, or how to combine them. To this aim, we create a multidimensional index that accounts for five dimensions of energy deprivation: two objective indicators of “low income, high costs,” and “high actual cost,” as well as three subjective indicators of “not warm enough home,” “housing faults,” and “bills difficulties.” We define households as poor if at least two forms of deprivation are present. We apply our measure to Poland. In 2017, 10% of households in Poland suffered from multidimensional energy poverty. Households living in buildings built before 1946, households living in rural areas, and households that were dependent on retirement and disability pensions were at the highest risk of multidimensional energy poverty.  相似文献   
55.
Steel matrix composites are being increasingly investigated because of their wear and corrosion properties, allowing their wide application in various industrial sectors. The interaction of tungsten carbide (WC) with the steel matrix, including an analysis of its volume share and particle size, is crucial in determining the resistance to wear and corrosion of the metal matrix composite (MMC). However, there is little information in the literature about sintered MMCs based on low-alloy steels. This paper presents the results of an analysis of the influence of the volume share of WC (5?vol.% and 20?vol.%) and carbide particle size (0.7?µm and 5.0?µm) on the resistance to abrasion of a friction pair: sintered composite and bearing steel, analysed using two rotational speeds (0.02?m/s and 0.2?m/s). Moreover, the resistance to corrosion in 3.5% NaCl solution is also characterized. It is shown that both the volume share and the size of the WC particles used as reinforcement of the steel matrix have a significant impact on the densification behaviour as well as the resistance to abrasive wear and corrosion of sintered MMCs based on low-alloy steel.  相似文献   
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The aim of this study was to determine the usability of fruits of selected species growing in Europe for the smoothies production. The organoleptic assessment, analysis of polyphenols and vitamin C content and antioxidant activity of products were determined. The panellists were most in favour of the smoothies containing cranberry, black currant and bilberry purees as well as juice from dog rose. Polymerised proanthocyanidins were found to predominate in most of the products, except for the black currant smoothies (B3) where the main group of polyphenols were anthocyanins. The content of proanthocyanidins was higher in the smoothies containing dog rose juice. The analysed products differed significantly in the content of vitamin C, as the highest content of ascorbic acid was determined in black currant smoothies with dog rose juice and bilberry puree (168.98 mg/100 g).  相似文献   
58.
This paper examines the applicability of DEA (Data Envelopment Analysis) to measure and evaluate the efficiency of materials management at the regional level. The research has been conducted for Polish regions as a case study. The basis for the calculation of the efficiency scores was a statistically selected set of materials used in a given region and the Gross Domestic Product (GDP). The results of the analysis reveal that 4 (Łódzkie, Śląskie, Warmińsko-Mazurskie, and Zachodniopomorskie) out of 16 Polish regions are relatively efficient. The remaining regions consume too many material resources in the process of generating goods and services.  相似文献   
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60.
ABSTRACT

Owing to the ability of electrodialysis to produce highly concentrated solutions from dilute stream, in this paper, the possibility of nickel recovery and concentration from real electroplating industrial waste was discussed. The results showed that the nickel content in solutions after electrodialysis was approximately two times higher than in the initial working solutions, and the nickel recovery exceeded 85%. The nickel electric current efficiency (CENi) depended upon the type of electroplating bath and its acidic behaviour. The CENi was in the range of 52.3–70.6%. Moreover, high boron and the total organic carbon retention coefficients equal to 88.92% and 93.93% respectively, were observed.  相似文献   
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