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Engineering operando methodology： Understanding catalysis in time and space

Frontiers of Chemical Science and Engineering 2018年第3期12卷 509-536页

作者： Raquel Portela susana perez-ferreras Ana Serrano-Lotina Miguel A. Banares Instituto de Catalisis y Petroleoquimica ICP-CSIC Marie Curie 2 Madrid Spain

The term operando was coined at the begin- ning of this century to gather the growing efforts devoted to establish structure-activity relationships by simulta- neously characterizing a catalyst performance and the relevant surface chemistry during genuine catalytic opera- tion. This approach is now widespread and consolidated; it has become an increasingly complex but efficient junction where spectroscopy, materials science, catalysis and engineering meet. While for some characterization techni- ques kinetically relevant reactor cells with good resolution are recently developing, the knowledge gained with magnetic resonance and X-ray and vibrational spectro- scopy studies is already huge and the scope of operando methodology with these techniques is recently expanding from studies with small amounts of powdered solids to more industrially relevant catalytic systems. Engineering catalysis implies larger physical domains, and thus all sort of gradients. Space- and time- resolved multi-technique characterization of both the solid and fluid phases involved in heterogeneous catalytic reactions （including temperature data） is key to map processes from different perspectives, which allows taking into account existing heterogeneities at different scales and facing up- and down-scaling for applications ranging from microstructured reactors to industrial-like macroreactors （operating with shaped catalytic bodies and/or in integral regime）. This work reviews how operando methodology is evolving toward engineered reaction systems.

关键词： operando structured catalysts spaceresolved time-resolved spectroscopy

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Formation potential and analysis of 32 regulated and unregulated disinfection by-products: Two new simplified methods

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Journal of Environmental Sciences 2022年第7期34卷 209-221页

作者： Jillian N.Murakami Xu Zhang Joanne Ye Amy M.MacDonald Jorge perez David W.Kinniburgh susana Y.Kimura Department of Chemistry University of CalgaryCalgaryAlbertaT2N 1N4Canada Alberta Centre for Toxicology University of CalgaryCalgaryAlbertaT2N 4N1Canada

Water disinfection is an essential process that provides safe water by inactivating pathogens that cause waterborne diseases. However, disinfectants react with organic matter naturally present in water, leading to the formation of disinfection by-products(DBPs). Multi-analyte methods based on mass spectrometry(MS) are preferred to quantify multiple DBP classes at once however, most require extensive sample pre-treatment and significant resources. In this study, two analytical methods were developed for the quantification of 32 regulated and unregulated DBPs. A purge and trap(P&T) coupled with gas chromatography mass spectrometry(GC-MS) method was optimized that automated sample pre-treatment and analyzed volatile and semi-volatile compounds, including trihalomethanes(THMs), iodinated trihalomethanes(I-THMs), haloacetonitriles(HANs), haloketones(HKTs) and halonitromethanes(HNMs). LOQs were between 0.02-0.4 μg/L for most DBPs except for 8 analytes that were in the low μg/L range. A second method with liquid chromatography(LC) tandem mass spectrometry(MS/MS) was developed for the quantification of 10 haloacetic acids(HAAs) with a simple clean-up and direct injection. The LC-MS/MS direct injection method has the lowest detection limits reported(0.2-0.5 μg/L). Both methods have a simple sample pre-treatment, which make it possible for routine analysis. Hyperchlorination and uniform formation conditions(UFC) formation potential tests with chlorine were evaluated with water samples containing high and low TOC. Hyperchlorination formation potential test maximized THMs and HAAs while UFC maximized HANs. Ascorbic acid was found to be an appropriate quencher for both analytical methods. Disinfected drinking water from four water utilities in Alberta, Canada were also evaluated.

关键词： Disinfection byproducts Purge and trap LC-MS/MS Drinking water DBP formation potential HAAs HANs

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Fiber Cavity Ring Down and Gain Amplification Effect

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Photonic Sensors 2016年第4期6卷 324-327页

作者： susana SILVA Regina MAGALHAES Rosa Ana perez-HERRERA Manuel LOPEZ-AMO M. B. MARQUES O. FRAZAO IINESC TEC Rua do Campo Alegre 687 4169-007 Porto Portugal Dept. de Fisica e Astronomia da Faculdade de Ciencias da Universidade do Porto Rua do Campo Alegre 687 4169-007 Porto Portugal public University of Navarra Dept. of Electric and Electronic Engineering Campus de Arrosadla Pamplona Spain.

The effect of an erbium-doped fiber amplifier （EDFA） placed inside the fiber ring of a cavity ring down （CRD） configuration is studied. The limitations and advantages of this configuration are discussed, and the study of the ring-down time as a function of the current applied and gain to the EDFA is also presented. In this case, the power fluctuations in the output signal are strongly dependent on the cavity ring-down time with the EDFA gain.

关键词： Cavity ring down EDFA multimode laser optical fibers.

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Effect of fosfomycin,Cynara scolymus extract,deoxynivalenol and their combinations on intestinal health of weaned piglets

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Animal Nutrition 2019年第4期5卷 386-395页

作者： Guadalupe Martinez susana N.Dieguez Maria B.Fernandez Paggi Maria B.Riccio Denisa S.perez Gaudio Edgardo Rodriguez Fabian A.Amanto Maria O.Tapia Alejandro L.Soraci Area Toxicología Departamento de FisiopatologíaFacultad de Ciencias VeterinariasUniversidad Nacional del Centro de la Provincia de Buenos AiresTandilB7000Buenos AiresArgentina Centro de Investigación Veterinaria de Tandil(CIVETAN) UNCPBA-CICPBA-CONICETFacultad de Ciencias VeterinariasCampus UniversitarioTandilB7000Buenos AiresArgentina Consejo Nacional de Investigaciónes Científicas-CONICET Buenos AiresC1425FQBArgentina Comisión de Investigaciónes Científicas de la Provincia de Buenos Aires(CIC-PBA) La PlataB1900Buenos AiresArgentina Area Producción Porcina Departamento de Producción AnimalFacultad de Ciencias VeterinariasUniversidad Nacional del Centro de La Provincia de Buenos AiresTandilB7000Buenos AiresArgentina Area Estadística Sanidad Animal y Medicina PreventivaFacultad de Ciencias VeterinariasUniversiclacl Nacional del Centro de la Provincia de Buenos AiresTandilB7000Buenos AiresArgentina

Weaning is a challenging stage of pig *** undergo environmental,social and dietary changes leading to weaning stress *** order to compensate for the detrimental effects of weaning stress,antibiotics and natural extracts are used as feed additives,sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in *** aim of this study was to evaluate the effect of fosfomycin(FOS),Cynara scolymus extract(CSE),deoxynivalenol(DON) and their combined administration on intestinal health of weaned *** experiment was designed as a 2×2×2 factorial arrangement with 3 factors(FOS,CSE and DON treatments),2 levels each(presence and absence) and 3 *** piglets(n=24)were randomly divided in groups to receive the different treatments,namely DON administered in diet(50 μg/kg BW),FOS administered into the drinking water(30 mg/kg BW),CSE administered in diet(15 mg/kg BW) and all their *** 15 d,the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH,Enterobacteriaceae to lactic acid bacteria(E:L) ratio,volatile fatty acid(VFA) concentrations,disaccharidase(lactase,sucrase and maltase)activity,histology(intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia *** our results,FOS and CSE treatments,individually or combined,produced a lower E:L ratio,an enhanced production of butyrate,increased disaccharidase activity(particularly maltase),and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal *** did not show interactions with the other factors and its administration produced decreases on VFA,disaccharidase activity and goblet cells *** conclusion,weaning piglets receiving diets containing FOS,CSE or both exhibited evident beneficial intestinal effects compared

关键词： Fosfomycin Cynara scolymus extract Deoxynivalenol Intestinal health Weaned piglets

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CORRELATION OF SHORT-WAVELENGTH AUTOMATED PEREMETRY INDICES TO OPTIC DISC TOPOGRAPHY

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国际眼科杂志 2003年第1期3卷 78-78页

作者： J.M.U.Larrosa A.ferreras V.Polo A.perez-Inigo F.M.Honrubia Depart-ment of Ophthalmology Miguel Servet University HospitalDepart-ment of Ophthalmology Miguel Servet University HospitalDepart-ment of Ophthalmology Miguel Servet University HospitalDepart-ment of Ophthalmology Miguel Servet University HospitalZaragoza University Spain

Purpose: To correlate structural parameters of the optic nerve head and global indices of short-wavelength automated perimetry (SWAP) in ocular hypertensives. Methods: The study included 195 eyes with ocular hypertension (IOP>21 mmHg, normal conventional automated perimetry). Short-wavelength automated perimetry was performed (full-threshold, 24-2). The optic

关键词：短波长自动视野检查指标视神经盘地形图相关性眼球指数高眼压

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