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51.
Tania Martellini Chiara Berlangieri Luigi Dei Emiliano Carretti Saul Santini Angelica Barone Alessandra Cincinelli 《Indoor air》2020,30(5):900-913
Indoor Air Quality monitoring in cultural institutions is of particular concern to protect these places and the cultural heritage content. An indoor monitoring campaign was performed in three museums in Florence (Italy) to determine the occurrence and levels of volatile organic compounds (VOCs). VOCs of interest included BTEX (benzene, toluene, ethylbenzene, xylenes), terpenes, aldehydes, organic acids, and cyclic volatile methyl siloxanes (cVMS). The most abundant VOCs in all samples analyzed were BTEX, which were strictly related to the traffic source, followed by siloxanes and terpenes. Among BTEX, toluene was always the most abundant followed by xylenes, ethylbenzene, and benzene. cVMS in exhibition rooms with the presence of visitors showed higher values compared to samples collected when the museums were closed. Terpenes showed not only the influence of vegetation-biogenic sources surrounding a museum but could also be related to the wood used for the construction of showcases and furniture and the use of cleaning products. Data obtained also showed the presence of organic acids and aldehydes whose source can be traced back to exhibits themselves and wood-based furniture. Assessing the levels of organic acids in museums is important because, over time, it can cause deterioration of the artifacts. 相似文献
52.
Chester J. Lau Max Loebel Roson Keifer M. Klimchuk Tania Gautam Boyang Zhao Ran Zhao 《Indoor air》2021,31(3):769-782
Household humidification is widely practiced to combat dry indoor air. While the benefits of household humidification are widely perceived, its implications to the indoor air have not been critically appraised. In particular, ultrasonic humidifiers are known to generate fine particulate matter (PM). In this study, we first conducted laboratory experiments to investigate the size, quantity, and chemical composition of PM generated by an ultrasonic humidifier. The mass of PM generated showed a correlation with the total alkalinity of charge water, suggesting that CaCO3 is likely making a major contribution to PM. Ion chromatography analysis revealed a large amount of SO42− in PM, representing a previously unrecognized indoor source. Preliminary results of organic compounds being present in humidifier PM are also presented. A whole-house experiment was further conducted at an actual residential house, with five low-cost sensors (AirBeam) monitoring PM in real time. Operation of a single ultrasonic humidifier resulted in PM2.5 concentrations up to hundreds of μg m−3, and its influence extended across the entire household. The transport and loss of PM2.5 depended on the rate of air circulation and ventilation. This study emphasizes the need to further investigate the impact of humidifier operation, both on human health and on the indoor atmospheric chemistry, for example, partitioning of acidic and basic compounds. 相似文献
53.
Metal‐Organic Framework Surface Functionalization: GraftFast Surface Engineering to Improve MOF Nanoparticles Furtiveness (Small 40/2018) 下载免费PDF全文
54.
Production of polyhydroxybutyrate (PHB) of high and ultra‐high molecular weight by Azotobacter vinelandii in batch and fed‐batch cultures 下载免费PDF全文
55.
Inés González‐Hidalgo Sancho Bañón José María Ros 《International Journal of Food Science & Technology》2012,47(4):674-681
The main by‐product from the table olive canning industry is the stone with some residual olive flesh. The purpose of this study was to evaluate the composition – phenolic compounds (hydroxytyrosol, tyrosol and oleuropein) and tocopherol – and the antioxidant activity in different fractions (flesh, stone and seed) from the table olive by‐product and the whole by‐product. The highest amounts of phenolic compounds (1710.0 ± 33.8 mg kg?1) as well as the highest antioxidant activity (8226.9 ± 9.9 hydroxytyrosol equivalents mg kg?1) were obtained in the seed. The highest amounts of hydroxytyrosol (854.8 ± 66.0 mg kg?1) and tyrosol (423.6 ± 56.9 mg kg?1) were found in the whole by‐product from the pepper stuffed olives, while the stone without seed had the maximum oleuropein content (750.2 ± 85.3 mg kg?1). α‐Tocopherol values were between 79.8 ± 20.8 mg kg?1 in the seed of the olive stone and 6.2 ± 1.2 mg kg?1 in the whole by‐product from the anchovy‐stuffed olives. In light of the results obtained, it would seem possible to use table olive by‐product as a source of natural antioxidants in foods, cosmetics or pharmaceutical products, thus contributing to diminishing the environmental impact of table olive by‐product and to its revalorisation. 相似文献
56.
Improved pretreatments applied to the sugarcane bagasse and release of lignin and hemicellulose from the cellulose‐enriched fractions by sulfuric acid hydrolysis 下载免费PDF全文
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Currently available treatments for the degenerated intervertebral disc present disadvantages, such as surgical invasiveness and inadequate load distribution results. Load-bearing, injectable materials may be interesting for future therapies, but have not been studied in depth. In this study, the existing literature was screened for studies on injectable materials for the intervertebral disc and a rationale for load-bearing, injectable materials was formulated. Requirements for such a material were discussed, partly based on the experience of materials used for similar applications. Important properties were discussed and found to include biocompatibility, bioactivity, porosity, handling, injectability, working time, setting time, radiopacity, containment and mechanical properties, where several of these properties are linked to one another. In conclusion, there is a need for consensus on the properties of new materials developed for use in minimally invasive procedures in the spine. A substantial amount of attention may need to be given to non-toxic setting reactions. 相似文献
60.
Tania Maree 《International journal of human-computer interaction》2017,33(12):963-972
The growing importance of social media and research interest in the field makes it imperative to consider the measures used to assess social networking site (SNS) use. The Facebook Intensity Scale has seen prolific use since its development; however, it has been criticized by some scholars. Jenkins-Guarnieri, Wright, and Johnson (2013) suggested another scale, the Social Media Use Integration Scale (SMUIS), which was developed to be suitable for use across different SNS platforms. They advised further research to confirm its psychometric properties, testing it on a more diverse sample than US college students and on social media other than Facebook. In this study, EFAs and a CFA were conducted to examine the validity of the SMUIS on Facebook and LinkedIn in the African context. The results provide preliminary evidence of the reliability and validity of the SMUIS for diverse age ranges. Further testing of the scale on LinkedIn is recommended. 相似文献