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991.
One of the most investigated heat transfer fluid or heat storage medium in the field of thermal solar conversion is the “solar salt”, a mixture of nitrates NaNO3/KNO3, 60/40% by weight, respectively. The content of potassium in this fluid allows exploiting the self activity of the isotope 40K to perform measurements useful for control or diagnostics of a solar plant. Here an experimental test on the non-invasive measurement of the salt level in a tank by means of gamma-ray spectrometry is shown. 相似文献
992.
Elena Orban Teresina Nevigato Maurizio Masci Gabriella Di Lena Irene Casini Roberto Caproni Loretta Gambelli Paola De Angelis Massimo Rampacci 《Food chemistry》2007,100(2):482-490
European perch (Perca fluviatilis) harvested from three lakes of Central Italy were studied in different seasonal periods of a year to evaluate their nutritional quality and some safety aspects related to the pollution of the aquatic environment. The lakes considered, located in the Latium region, differed with respect to their volcanic (Bolsena and Bracciano Lakes) or artificial (Salto Lake) origin. Fillets of fish caught in the three lakes were characterised by good protein (17–19%) and mineral contents and low lipid levels (0.6–1.2%) throughout the year. Total lipids were characterised by low cholesterol levels (41.9–74.7 mg/100 g) and high percentages of total n − 3 polyunsaturated fatty acids (27.7–33.8% of total fatty acids), in particular docosahexaenoic acid (14.2–25.3% of total fatty acids). The qualitative analysis of the stomach content of perch confirmed their predatory feeding behaviour. The chemical and nutritional profiles of perch from the three lakes were comparable except for rubidium and cesium levels, which were higher in the muscle tissues of perch from the volcanic lakes. These minerals may represent elements of traceability of the origin of fish. Low levels of organochlorine pesticides and polychlorinated biphenyls, well below the Italian and European action limits, were detected in the muscle tissue of perch from all three lakes. 相似文献
993.
Roberto Grena 《Solar Energy》2009,83(8):1186-1199
A transient simulation of the heat transfer in a particle directly heated by the sun, in a falling-particle receiver, is presented. The local temperature can have a non-uniform distribution, that depends on many factors, such as the size of the particle, its rotation, and the exposition time. This fact should be considered when studying the material resistance and aging, or direct chemical reactions in the falling particle. The single-particle simulation presented here can be useful to test the validity of the global fluid dynamics simulations, to study single-particle related aspects such as aging, thermal stresses and chemical stability, to study the distribution of temperature if the particles are not uniform in size, or to study the efficiency in chemical applications. 相似文献
994.
The use of two agro-residues (liquid cassava waste and orange essential oil) in the biotransformation of R-(+)-limonene was investigated. The main components of orange essential oil were determined by GC–MS and R-(+)-limonene was shown to be the predominant constituent, accounting for more than 94% of the total content. Cassava wastewater proved to be a suitable substrate for mycelial growth, leading to good, rapid growth with all the fungal strains tested, reaching 29.4 g/l (dry weight) after 3 days of growth (Penicillium sp. 2025). The best R-(+)-α-terpineol yields were achieved when the strains were grown in cassava media and the mycelia then transferred to a new flask containing mineral medium and orange essential oil as the sole C- and energy source. One of the strains tested, Fusarium oxysporum 152B, converted R-(+)-limonene to R-(+)-α-terpineol, yielding nearly 450 mg/l after 3 days of transformation. Growth in the presence of a solution of 1% orange essential oil in decane did not increase the transformation yields. 相似文献
995.
Mario Olivieri Nicola Murgia Anne‐Elie Carsin Joachim Heinrich Geza Benke Roberto Bono Angelo Guido Corsico Pascal Demoly Bertil Forsberg Thorarinn Gislason Christer Janson Rain Jgi Bndicte Leynaert Jesús Martínez‐Moratalla Rovira Dan Norbck Dennis Nowak Silvia Pascual Isabelle Pin Nicole Probst‐Hensch Chantal Raherison Torben Sigsgaard Cecilie Svanes Kjell Torn Isabel Urrutia Joost Weyler Deborah Jarvis Jan‐Paul Zock Giuseppe Verlato 《Indoor air》2019,29(4):670-679
This longitudinal study investigated whether smoking bans influence passive smoking at work and/or at home in the same subjects. Passive smoking at work and/or at home was investigated in random population samples (European Community Respiratory Health Survey) in 1990‐1995, with follow‐up interviews in 1998‐2003 and 2010‐2014. National smoking bans were classified as partial (restricted to public workplaces) or global (extended to private workplaces). Multivariable analysis was accomplished by three‐level logistic regression models, where level‐1, level‐2, and level‐3 units were, respectively, questionnaire responses, subjects, and centers. Passive smoking at work was reported by 31.9% in 1990‐1995, 17.5% in 1998‐2003, and 2.5% in 2010‐2014. Concurrently, passive smoking at home decreased from 28.9% to 18.2% and 8.8%. When controlling for sex, age, education, smoking status, and ECHRS wave, the odds of passive smoking at work was markedly reduced after global smoking bans (OR = 0.45, 95% CI 0.25‐0.81), particularly among non‐smokers, while the protective effect of global smoking bans on passive smoking at home was only detected in non‐smokers. Smoking bans both in public and private workplaces were effective in reducing passive smoking at work in Europe. However, given the inefficacy of smoking bans in current smokers’ dwellings, better strategies are needed to avoid smoking indoors. 相似文献
996.
Malandrino Delfina De Prisco Roberto Ianulardo Mario Zaccagnino Rocco 《Data mining and knowledge discovery》2022,36(4):1301-1334
Data Mining and Knowledge Discovery - Plagiarism is a controversial and debated topic in different fields, especially in the Music one, where the commercial market generates a huge amount of money.... 相似文献
997.
Posenato Roberto Lanz Andreas Combi Carlo Reichert Manfred 《Software and Systems Modeling》2019,18(2):1135-1154
Software and Systems Modeling - Managing temporal process constraints in a suitable way is crucial for long-running business processes in many application domains. However, proper support of... 相似文献
998.
Cabrera Jr. Enrique Estruch-Juan Elvira Gómez Elena del Teso Roberto 《Water Resources Management》2022,36(9):3247-3264
Water Resources Management - Regulation in the water sector emerged as a formula to protect customers from the natural monopoly that conforms water and wastewater services. As there is little... 相似文献
999.
Antonela G. Garzón Roberto L. Torres Silvina R. Drago 《International Journal of Food Science & Technology》2019,54(5):1901-1908
Effects of white sorghum brewing process on free amino-acids, γ-aminobutyric acid (GABA), phenolics and bioactivity, including antioxidant (by ABTS+ and reducing power, RP, methods), antihypertensive (angiotensin converting enzyme-I, ACE-I inhibition assay), and hypoglycaemic activity (α-glucosidase inhibition assay) were evaluated. From the wort to the beer, free amino acids decreased, but GABA and phenolics increased significantly, positively modifying the bioactive potential. ABTS and α-glucosidase inhibition activity correlated positively with at least one of the phenolic acids evaluated. Ale white sorghum beer presented high content of GABA (7.8 mg L−1), phenolics (40.7 mg total phenolic acids L−1), antioxidant activity (9.14 mmol Trolox equivalent L−1, and 48.8 mmol ascorbic acid equivalent L−1, for ABTS+ and RP, respectively), and exhibit ACE-I inhibition (1.0 μg captopril equivalent L−1) and α-glucosidase inhibition (34.5 mg acarbose equivalent L−1) activities. The level of bioactive compounds and its low ethanol content (2.3%), make beer obtained from malted white sorghum a potential functional beverage. 相似文献