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Stephen E. Musson Pablo Campo Makram Suidan 《The Science of the total environment》2010,408(9):2068-2074
Research examined the anaerobic degradation of 17α-ethynylestradiol, acetaminophen, acetylsalicylic acid, ibuprofen, metoprolol tartrate, and progesterone by methanogenic bacteria. Using direct sample analysis and respirometric testing, anaerobic degradation was examined with (a) each compound as the sole organic carbon source and (b) each compound at a lower concentration (250 µg/L) and cellulose serving as the primary organic carbon source. The change in pharmaceutical concentration was determined following 7, 28, 56, and 112 days of anaerobic incubation at 37 °C. Only acetylsalicylic acid demonstrated significant degradation; the remaining compounds showed a mixture of degradation and abiotic removal mechanisms. Experimental results were compared with BIOWIN, an anaerobic degradation prediction model of the US Environmental Protection Agency. The BIOWIN model predicted anaerobic biodegradability of the compounds in the order: acetylsalicylic acid > metoprolol tartrate > ibuprofen > acetaminophen > 17α-ethinylestradiol > progesterone. This corresponded well with the experimental findings which found degradability in the order: acetylsalicylic acid > metoprolol tartrate > acetaminophen > ibuprofen. 相似文献
995.
Julia Andreeva Max Boehm Benjamin Gaidioz Edward Karavakis Lukasz Kokoszkiewicz Elisa Lanciotti Gerhild Maier William Ollivier Ricardo Rocha Pablo Saiz Irina Sidorova 《Journal of Grid Computing》2010,8(2):323-339
The Large Hadron Collider (LHC) is preparing for data taking at the end of 2009. The Worldwide LHC Computing Grid (WLCG) provides data storage and computational resources for the high energy physics community. Operating the heterogeneous WLCG infrastructure, which integrates 140 computing centers in 33 countries all over the world, is a complicated task. Reliable monitoring is one of the crucial components of the WLCG for providing the functionality and performance that is required by the LHC experiments. The Experiment Dashboard system provides monitoring of the WLCG infrastructure from the perspective of the LHC experiments and covers the complete range of their computing activities. This work describes the architecture of the Experiment Dashboard system and its main monitoring applications and summarizes current experiences by the LHC experiments, in particular during service challenges performed on the WLCG over the last years. 相似文献
996.
María J. Martín de Vidales Cristina Sáez Pablo Cañizares Manuel A. Rodrigo 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2012,87(2):225-231
BACKGROUND: Metoprolol is a beta‐blocker that can be found in urban wastewaters and which is not removed efficiently by conventional wastewater treatments. In this work, the removal of this pollutant by conductive diamond electrochemical oxidation (CDEO) is studied. RESULTS: CDEO is able to degrade Metoprolol tartrate down to the 10 ppb level (detection limit of the technique used) with a current charge requirement that increases with increase in the initial concentration of pollutant, although it is many times greater than the stoichiometric current charge required. CDEO also removed very efficiently the reaction intermediates. In terms of TOC the depletion follows a first‐order kinetic, but the kinetic constant of Metoprolol decreases with concentration. NaCl increases significantly Metoprolol degradation rate, but it barely affects the TOC removal rate. CONCLUSIONS: CDEO can be used to remove Metoprolol from wastewaters, independently of the initial concentration of compound. Several reaction intermediates are formed during the electrolyses although their concentrations are very low and negligible compared with that of Metoprolol. The removal rate (in terms of TOC) does not depend on the nature of the electrolyte used. The process is under mass transfer control for the complete range of concentrations studied. Copyright © 2011 Society of Chemical Industry 相似文献
997.
María del Rosario Acquisgrana Laura Cecilia Gomez Pamies Nancy María Jimena Martinez Amezaga Fernanda Micaela Quiroga Pablo Daniel Ribotta Elisa Inés Benítez 《International Journal of Food Science & Technology》2020,55(7):2901-2909
The present work evaluates the potential of sorghum with high content of tannins for wholegrain flour production. Two types of mills were used: a roller mill (RM) and a blade (BM) mill. The impact of moisture and grinding on yield, physical, chemical and thermal properties were evaluated. Maximum yield was obtained using a BM with 25% moisture in the grain, resulting in 60.9% versus 28% (g flour g−1 of wholegrain sorghum) for the RM. Grain moisture and milling type affected flour colour and ashes. For both mills, the pasting and thermal properties of flour with grain moisture variation were significantly different from the untreated control sample. By studying the procedures for flour production and quality characteristics, it is possible to produce flour with good physical attributes, which can contribute to the development of gluten-free foods based on sorghum for the coeliac population. 相似文献
998.
Rice husk lean-combustion in a bubbling and atmospheric fluidized bed reactor (FBR) of 0.3 m diameter with expansion to 0.4 m in the freeboard zone and 3 m height was investigated. Experiment design - response surface methodology (RSM) - is used to evaluate both excess air and normal fluidizing velocity influence (independent and controllable variables), in the combustion efficiency (carbon transformation), bed and freeboard temperature and silica content in the ashes. Hot gases emissions (CO2, CO and NOx), crystallographic structure and morphology of the ash are also shown. A cold fluidization study is also presented. The values implemented in the equipment operation, excess air in the range of 40-125% and normal fluidization velocities (0.13-0.15 Nm/s) show that the values near the lower limit, encourage bed temperatures around 750 °C with higher carbon transformation efficiencies around 98%. However, this condition deteriorated the amorphous potential of silica present in the ash. An opposite behavior was evidenced at the upper limit of the excess air. This thermochemical process in this type of reactor shows the technical feasibility to valorize RH producing hot gases and an amorphous siliceous raw material. 相似文献
999.
Teliz Erika Diez Joaquin Martínez Marcos Díaz Pablo Pignanelli Fernando Faccio Ricardo Zinola Carlos F. Díaz Verónica 《JOM Journal of the Minerals, Metals and Materials Society》2019,71(6):1952-1961
JOM - Three specimens were synthesized presenting the following stoichiometry: Zr1?xTixCr0.7Mo0.3Ni (x?=?0.3; 0.5; 0.7). The substitution of zirconium atoms by a lower atomic... 相似文献
1000.
González García Cristian Núñez-Valdez Edward Rolando Moreno-Ger Pablo González Crespo Rubén Pelayo G-Bustelo B. Cristina Cueva Lovelle Juan Manuel 《Universal Access in the Information Society》2019,18(3):599-614
Universal Access in the Information Society - Educational video games are becoming an increasingly popular alternative in the academic field. However, video game development is a very complex task... 相似文献