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Single atom Cu-N-C catalysts for the electro-reduction of CO_(2) to CO assessed by rotating ring-disc electrode

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journal of Energy Chemistry 2024年第1期88卷 169-182,I0004页

作者： S.Pérez-Rodríguez M.gutiérrez-Roa C.Giménez-Rubio D.Ríos-Ruiz P.Arévalo-Cid M.V.Martínez-Huerta A.Zitolo M.j.Lázaro D.Sebastián Instituto de Carboquímica(CSIC) Miguel Luesma Castán 450018 ZaragozaSpain Instituto de Catálisis y Petroleoquímica(CSIC) Marie Curie 228049 MadridSpain Synchrotron SOLEIL L’Orme des MerisiersDépartementale 12891190France

The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V ***) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.

关键词： Cu-N-C Carbon xerogel Rotating ring disc electrode Carbon dioxide reduction reaction Carbon monoxide

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO javier PRECIADO-GARBAYO jorge SEVIL Francisco gutiErrez juan jMARTiNEZ Sonia MARTiN-LOPEZ Miguel GONZALEZ-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

Error field penetration in j-TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j-TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly jumps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

Impact of payment source, referral site, and place of residence on outcomes after allogeneic transplantation in Mexico

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World journal of Transplantation 2024年第2期14卷 76-87页

作者： Andrés Gómez-De León Yesica A López-Mora Valeria García-Zárate Ana Varela-Constantino Sergio U Villegas-De Leon Xitlaly j González-Leal Raúl del Toro-Mijares Anna C Rodríguez-Zúñiga juan F Barrios-Ruiz Victor Mingura-Ledezma Perla R Colunga-Pedraza Olga G Cantú-Rodríguez César H gutiérrez-Aguirre Luz Tarín-Arzaga Elías E González-López David Gómez-Almaguer Hematology Service Universidad Autónoma de Nuevo LeónFacultad de Medicina y Hospital Universitario Dr.JoséEleuterio GonzálezMonterrey 64460Nuevo LeónMexico Hemato-logy Service Clínica Gómez AlmaguerMonterrey 64710Nuevo LeónMexico Hematology Service Instituto Tecnológico de Estudios Superiores de MonterreyTec SaludEscuela de Medicina Ignacio SantosMonterrey 64710Nuevo LeónMexico

BACKGROUND The impact of social determinants of health in allogeneic transplant recipients in low-and middle-income countries is poorly *** observational study analyzes the impact of place of residence,referring institution,and transplant cost coverage(out-of-pocket vs government-funded vs private insurance)on outcomes after allogeneic hematopoietic stem cell transplantation(alloHSCT)in two of Mexico's largest public and private *** To evaluate the impact of social determinants of health and their relationship with outcomes among allogeneic transplant recipients in *** In this retrospective cohort study,we included adolescents and adults≥16 years who received a matched sibling or haploidentical transplant from *** were selected without regard to their diagnosis and were sourced from both a private clinic and a public University Hospital in *** payment groups were compared:Out-of-pocket(OOP),private insurance,and a federal Universal healthcare program“Seguro Popular”.Outcomes were compared between referred and institution-diagnosed patients,and between residents of Nuevo Leon and *** outcomes included overall survival(OS),categorized by residence,referral,and payment *** outcomes encompassed early mortality,event-free-survival,graft-versus-host-relapse-free survival,and non-relapse-mortality(NRM).Statistical analyses employed appropriate tests,Kaplan-Meier method,and Cox proportional hazard regression *** software included SPSS and R with tidycmprsk *** Our primary outcome was overall *** included 287 patients,n=164 who lived out of state(57.1%),and n=129 referred from another institution(44.9%).The most frequent payment source was OOP(n=139,48.4%),followed by private insurance(n=75,26.1%)and universal coverage(n=73,25.4%).No differences in OS,event-free-survival,NRM,or graft-versus-host-relapse-free survival were observed for patients dia

关键词： Hematopoietic cell transplant Social determinants of health Geography Haploidentical Out-of-pocket Financial toxicity Survival Health services and outcomes Hematopoietic malignancy Aplastic anemia

A Protocol for Fractal Studies on Porosity of Porous Media: High Quality Soil Porosity Images

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journal of Earth Science 2017年第5期28卷 888-896页

作者： Carlos García-gutiérrez Fernando San josé Martínez j.Caniego Dpto.Matemática Aplicada E.T.S.I.Navales Universidad Politécnica de Madrid Dpto.Matemática Aplicada E.T.S.I.Agrónomos Universidad Politécnica de Madrid

A protocol for obtaining digital images from natural porous media with a wide range of pore sizes, intended for fractal studies of the porosity, is proposed. Soil porosity is used as para- digm of complex natural porous media in this study. The use of several imaging devices and fluores- cent compounds to enhance the contrast between the solid and the pore phase is tested. Finally a protocol is reached using a photo camera and a confocal microscope. It is the first time that confocal microscopy is used for this purpose. Artificial porous images are created through random Sierpinski carpet fractals and the statistical information of real soil images. These ground truth images are used in an objective comparison of automatic segmentation algorithms for the obtained images. A statistical classification on the performance of several automatic segmentation algorithms for this tv^e of images is reached.

关键词： porous media micromorphology image segmentation confocal microscope fractal,porosity photography.

Modified activated carbon with interconnected fibrils of iron-oxyhydroxides using Mn^(2+) as morphology regulator, for a superior arsenic removal from water

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journal of Environmental Sciences 2019年第2期31卷 403-414页

作者： Cesar Nieto-Delgado joel gutiérrez-Martínez j.Rene Rangel-Méndez Environmental Sciences Division Potosino Institute of Scientific and Technological ResearchIPICyT

The arsenic removal efficiency of iron-modified activated carbons depends greatly on the number of available iron oxide surface sites, which are given by the surface area of the anchored particles. In this sense, aiming the generation of an adsorbent with superior arsenic adsorption capacity, we developed a protocol to anchor interconnected fibrils of iron oxyhydroxides, using Mn^(2+) as a morphology regulator. The protocol was based on a microwave-assisted hydrothermal method, using bituminous based activated carbon and both Fe^(2+) and Mn^(2+) ions in the hydrolysis solution. The elemental analysis of modified carbons revealed that Mn does not anchor to the carbon. However, when Mn is included in the hydrolysis solution, the iron content in the activated carbon increased up to 3.5 wt%,without considerable decreasing the adsorbent surface area. Under specific hydrothermal conditions, the Mn^(2+) promoted the formation of iron oxide nanoparticles shaped as interconnected fibrils. This material showed a superior arsenic adsorption capacity in comparison to similar iron modified activated carbons(5 mg As/g carbon, at 2 mg As/L),attributed to the increase in quantity and availability of active sites located on the novel interconnected fibrils of iron oxyhydroxides nanostructures.

关键词： Iron oxide nanostructures Hydrothermal synthesis Microwave Adsorption capacity Kinetics

Surface Properties of Fe_4N Compounds Layer on AISI 4340 Steel Modified by Pulsed Plasma Nitriding

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journal of Materials Science & Technology 2013年第3期29卷 287-290页

作者： j.C.Díaz-Guillén G.Vargas-gutiérrez E.E.Granda-gutiérrez j.S.Zamarripa-Pia S.I.Pérez-Aguilar j.Candelas-Ramírez L.lvarez-Contreras Centro de Investigacin en Materiales Avanzados S.C.Miguel de Cervantes 120Complejo Industrial ChihuahuaC.P.31109 ChihuahuaChihuahuaMexico Corporacin Mexicana de Investigacin en Materiales S.A.de C.V.Ciencia y Tecnología No 790Fracc.Saltillo 400C.P.25290 SaltilloCoahuilaMexico Centro de Investigacin y Estudios Avanzados del IPN Unidad SaltilloCarretera Saltillo Monterrey km 13Apdo.Postal 663C.P.25000 SaltilloCoahuilaMexico

In this work, the effect of nitriding current density on hardness, crystalline phase composition, layer thickness and corrosion rate of AlSl 4340 steel has been studied. X-ray diffraction analysis shows that thin layers formed during nitriding process are constituted of 7-Fe4N for samples processed between 1 and 2.5 mA/cm2. Thickness of nitrided layer increases proportionally to current density （0 μm for 0.5 mA/cm2 to 15 pm for 2.5 mA/cm2）. Plasma nitriding increased the surface hardness from 300 HV50g for untreated sample, to around 800HV5og for nitrided samples at 1 mA/cm2. While the untreated samples exhibited a corrosion rate of 0.153 mm per year, the corrosion performance was improved up to 0.03 mm per year at current densities above 1 mA/cm2, which is about one fifth of the corrosion rate of the untreated sample.

关键词： Plasma nitriding Current density Hardness Corrosion

Prediction of seakeeping in the early stage of conventional monohull vessels design using artificial neural network

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journal of Ocean Engineering and Science 2023年第4期8卷 344-366页

作者： P.Romero-Tello j.E.gutiérrez-Romero B.Serván-Camas Departamento de Física Aplicada y Tecnología Naval Universidad Politécnica de Cartagena(UPCT)CartagenaMurciaSpain Centre Internacional de Mètodes Numèrics en Enginyeria(CIMNE) BarcelonaSpain

Nowadays seakeeping is mostly analyzed by means of model testing or numerical *** require a significant amount of time and the exact hull geometry,and therefore seakeeping is not taken into account at the early stages of ship *** the main objective of this work is the development of a seakeeping prediction tool to be used in the early stages of ship *** tool must be fast,accurate,and not require the exact hull *** this end,an artificial intel-ligence(AI)algorithm has been *** algorithm is based on Artificial Neural Networks(ANNs)and only requires a number of ship coefficients of *** methodology developed to obtain the predictive algorithm is presented as well as the database of ships used for training the *** data were generated using a frequency domain seakeeping code based on the boundary element method(BEM).Also,the AI predictions are compared to the BEM results using both,ship hulls included and not included in the *** a result of this work it has been obtained an AI tool for seakeeping prediction of conventional monohull vessels.

关键词： artificial neural database

Storing Freshwater Versus Storing Electricity in Power Systems with High Freshwater Electric Demand

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 323-333页

作者： Mubarak j.Al-Mubarak Antonio j.Conejo Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOHUSA Department of Electrical Engineering Kuwait UniversityP.O.Box 5969Safat 13060Kuwait Department of Integrated Systems Engineering and the Department of Electrical and Computer Engineering The Ohio State UniversityColumbusOH 43210USA IEEE

We consider a power system whose electric demand pertaining to freshwater production is high(high freshwater electric demand),as in the Middle East,and investigate the tradeoff of storing freshwater in tanks versus storing electricity in batteries at the day-ahead operation *** storing freshwater and storing electricity increase the actual electric demand at valley hours and decrease it at peak hours,which is generally beneficial in term of cost and ***,to what extent?We analyze this question considering three power systems with different generation-mix configurations,i.e.,a thermal-dominated mix,a renewable-dominated one,and a fully renewable *** generation-mix configurations are inspired by how power systems may evolve in different countries in the Middle *** production uncertainty is compactly modeled using chance *** draw conclusions on how both storage facilities(freshwater and electricity)complement each other to render an optimal operation of the power system.

关键词： Power system operation freshwater production and transportation coordination day-ahead scheduling