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Quasi-in vivo corrosion behavior of AZ31B Mg alloy with hybrid MWCNTs-PEO/PCL based coatings

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Journal of Magnesium and Alloys 2022年第11期10卷 3217-3233页

作者： Morteza Daavari Masoud Atapour Marta Mohedano hugo mora Sánchez Juan Rodríguez-hernández Endzhe Matykina Raul Arrabal Aboozar Taherizadeh Department of Materials Engineering Isfahan University of Technology84156-83111 IsfahanIran Departamento de Ingeniería Química y de Materiales Facultad de Ciencias QuímicasUniversidad Complutense28040 MadridSpain Institute of Polymer Science and Technology(CSIC) Polymer Functionalization GroupMadrid 28006Spain

This study investigated the effects of multi-walled carbon nanotubes(MWCNTs) and polycaprolactone(PCL) on the quasi-in vivo corrosion behavior of AZ31B Mg alloy treated by plasma electrolytic oxidation(PEO). Thin(~2 μm, PCTPCL4) and thick(~60 μm, PCTPCL6) PCL layers were applied only onto the MWCNTs-PEO coating(PCT) as it showed better corrosion performance. Findings reveal that incorporation of MWCNTs induced several structural and functional modifications in the PEO coating, such as increased roughness, a thicker inner barrier layer, and reduced ***-in vivo corrosion testing was carried out under controlled temperature, p h, and fluid flow in simulated body fluid(SBF) by electrochemical impedance spectroscopy(EIS) and hydrogen evolution experiments. EIS results revealed that, after 48 h immersion, a diffusion process controlled hydration of the ceramic coatings. Comparison of the collected hydrogen after 15 days of immersion in the quasi-in vivo environment revealed that the PEO and PCT ceramic coatings decreased hydrogen generation by up to 74% and 91%, respectively, compared to non-coated ***6 coating exhibited the lowest amount of collected hydrogen(0.2 m L/cm^(2)). The thick PCL layer delayed the onset of substrate corrosion for at least 120 h, reducing the corrosion rate by 85% compared with the PCT.

关键词： AZ31B Mg alloy Plasma electrolyte oxidation(PEO) Multi-walled carbon nanotubes(MWCNTs) Quasi-in vivo condition Polycaprolactone(PCL)

P-functionalized carbon nanotubes promote highly stable electrocatalysts based on Fe-phthalocyanines for oxygen reduction: Experimental and computational studies

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Journal of Energy Chemistry 2022年第9期31卷 276-290,I0008页

作者： Beatriz Martinez-sanchez Diego Cazorla-Amors Emilia morallon Departamento de Quimica Fisica and Instituto Universitario de Materiales de Alicante(IUMA)University of Alicante Ap.99.03080 AlicanteSpain Departamento de Quimica Inorganica and Instituto Universitario de Materiales de Alicante(IUMA) University of AlicanteAp.9903080 AlicanteSpain

Iron(Ⅱ) phthalocyanines(FePc) supported on functionalized nanostructured carbon materials have been studied as electrocatalysts for the oxygen reduction reaction(ORR) in an alkaline medium. herein, two types of carbon nanotubes(CNTs) have been explored as support, Single-Walled Carbon Nanotubes and herringbone Carbon Nanotubes(SWCNTs and h CNTs, respectively), both electrochemically modified with ortho-aminophenylphosphonic acid(2APPA), which provides phosphate axial coordinating ligands for the immobilization of FePc molecules. All the catalysts were prepared via a facile incipient wetness impregnation method. Comprehensive experimental analysis together with density functional theory(DFT) calculations has demonstrated both the importance of the five-coordinated Fe macrocycles that favor the interaction between the FePc and the carbon support, as well as the effect of the CNT structure in the ORR. FePc axial coordination provides a better dispersion, leading to higher stability and a favorable electron redistribution that also tunes the ORR performance by lowering the stability of the reaction intermediates. Interestingly, such improvement occurs with a very low content of metal(~1 wt% Fe),which is especially remarkable when h CNT support is employed. This work provides a novel strategy for the development of Fe-containing complexes as precious metal-free catalysts towards the ORR.

关键词： Carbon nanotubes Iron phthalocyanine Oxygen reduction Electrocatalysis Axial ligand

TiO_(2) Nanocrystals Grown on Graphene as Advanced Photocatalytic hybrid Materials

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Nano Research 2010年第10期3卷 701-705页

作者： Yongye Liang hailiang Wang hernan sanchez Casalongue Zhuo Chen hongjie Dai Department of Chemistry and Laboratory for Advanced Materials Stanford UniversityStanfordCA 94305USA

A graphene/TiO_(2) nanocrystals hybrid has been successfully prepared by directly growing TiO_(2) nanocrystals on graphene oxide(GO)*** direct growth of the nanocrystals on GO sheets was achieved by a two-step method,in which TiO_(2) was first coated on GO sheets by hydrolysis and crystallized into anatase nanocrystals by hydrothermal treatment in the second *** hydrolysis induced by the use of EtOh/h2O mixed solvent and addition of h2SO4 facilitates the selective growth of TiO_(2) on GO and suppresses growth of free TiO_(2) in *** method offers easy access to the GO/TiO_(2) nanocrystals hybrid with a uniform coating and strong interactions between TiO_(2) and the underlying GO *** strong coupling gives advanced hybrid materials with various applications including *** prepared graphene/TiO_(2) nanocrystals hybrid has superior photocatalytic activity to other TiO_(2) materials in the degradation of rhodamine B,showing an impressive three-fold photocatalytic enhancement over *** is expected that the hybrid material could also be promising for various other applications including lithium ion batteries,where strong electrical coupling to TiO_(2) nanoparticles is essential.

关键词： Graphene titanium oxide photocatalyst hydrolysis

Intraexaminer repeatability and agreement in stereoacuity measurements made in young adults

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 374-381页

作者： Beatriz Antona Ana Barrio Isabel sanchez Enrique Gonzalez Guadalupe Gonzalez Department of Optics II (Optometry and Vision) Faculty of Optics and Optometry Complutense University of Madrid

AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and ***: Stereoacuity was measured in two different sessions separated by a time interval of at least 24 h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular ***: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability(COR): ±13 and±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was *** the subjects with abnormal binocular vision, best repeatability was shown by the Frisby(COR: ±69s arc)and Randot(COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other ***:Therepeatabilityofstereoacuitymeasures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.

关键词： stereoacuity repeatability agreement tereopsis

healthy diet,depression and quality of life:A narrative review of biological mechanisms and primary prevention opportunities

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World Journal of Psychiatry 2021年第11期11卷 997-1016页

作者： Octavio Pano Elena h Martínez-Lapiscina Carmen Sayón-Orea Miguel Angel Martinez-Gonzalez Jose Alfredo Martinez Almudena sanchez-Villegas Preventive Medicine and Public health University of NavarrePamplona 31008Spain Department of Neurology Center of Neuroimmunology Hospital Clinic of BarcelonaInstitut d’Investigacions Biomèdiques August Pi SunyerBarcelona 08036Spain Department of Preventive Medicine and Public health University of NavarraPamplona 31008Spain IdiSNA Navarra Institute for Health ResearchPamplona 31008Spain Department of Public health Navarra Institute of Public Health and EpidemiologyPamplona 31003Spain CIBER Pathophysiology of Obesity and Nutrition Institute of Health Carlos IIIMadrid 28049Spain Department of Nutrition Harvard T.H.Chan School of Public HealthBostonMA 02115United States Department of Food Sciences and Physiology University of NavarrePamplona 31008Spain Precision Nutrition and Cardiometabolic health Program IMDEA Food InstituteMadrid 28049Spain Department of Clinical Sciences University of Las Palmas Gran CanariaLas Palmas Gran Canaria 35080Spain

Unipolar depressive disorder(UDD)affects more than 264 million people worldwide and was projected well before the severe acute respiratory syndrome coronavirus 2 pandemic to be the leading cause of disability-adjusted life years lost in *** is imperative for leading economies to implement preventive strategies targeted towards UDD,given consistent policies are currently *** established similarities between the aetiological hypotheses of depression and cardiometabolic diseases are shifting paradigms within this *** is believed that dietary practices could potentially reduce the incidence of depression;similar to their effects on ***,the aim of this review was to compile current evidence on healthy dietary patterns as suitable contributors towards primary prevention strategies against *** of the well-known biological mechanisms behind depression have been positively associated with healthful diets and dietary patterns to varying ***,a common factor of UDD is the production and overall effects of inflammatory cytokines,such as interleukin-6,tumor necrosis factor-α,and Creactive *** compounds have been associated with depressive symptoms,disturbances in neuroendocrine function,leaky gut,monoamine activity and brain function,while also being key factors in the development of cardiometabolic *** Mediterranean diet(MD)in particular,is well supported by first-level evidence regarding its preventive qualities against metabolic and cardiovascular diseases and thus considered a model for healthy eating by various *** one of the few clinical trials investigating these associations,the PREDIMED trial,individuals with diabetes assigned to a MD supplemented with mixed tree nuts experienced a 41%relative risk reduction for developing ***,there is a need to include health related quality of life as an indicator of physical and mental well-being,considering its putative associations

关键词： Depression Nutrition Mediterranean Quality of life Primary prevention Epidemiology

Numerical Approximation of Fractal Dimension of Gaussian Stochastic Processes

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Applied Mathematics 2014年第12期5卷 1763-1772页

作者： Freddy h. Marin sanchez William Eduardo Alfonso Basic Science Department EAFIT University Carrera 49 # 7 Sur-50 Medellín Colombia

In this paper we propose a numerical method to estimate the fractal dimension of stationary Gaussian stochastic processes using the random Euler numerical scheme and based on an analytical formulation of the fractal dimension for filtered stochastic signals. The discretization of continuous time processes through this random scheme allows us to find, numerically, the expected value, variance and correlation functions at any point of time. This alternative method for estimating the fractal dimension is easy to implement and requires no sophisticated routines. We use simulated data sets for stationary processes of the type Random Ornstein Uhlenbeck to graphically illustrate the results and compare them with those obtained whit the box counting theorem.

关键词： Stationary Gaussian Stochastic Processes Fractal Dimension Random Euler Numerical Scheme

Uncertainty and Sensitivity Analysis for the hELIOS Loop within the LACANES Benchmark

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Journal of Energy and Power Engineering 2011年第6期5卷 515-524页

作者： W. Jaeger V.h. sanchez Espinoza Institute for Neutron Physics and Reactor Technology Karlsruhe Institute of Technology Eggenstein-Leopoldshafen 76344Germany

Within the OECD/NEA Benchmarking of Thermal-hydraulic Loop Models for Lead-Alloy Cooled Advanced Nuclear Energy Systems （LACANES）, the Institute for Neutron Physics and Reactor Technology takes part in the validation process of system codes and the characterization of the thermal-hydraulic behavior of an experimental loop operated with liquid lead-bismuth-eutectics. To confirm the calculations, the results were compared to experimental data obtained from the hELIOS facility at the Seoul National University and to the results of other benchmark participants. The comparison showed that the calculations are within measurement tolerance but nevertheless discrepancies among the participants exist. The pressure drop estimation is determined by a variety of empirical correlations for the friction and the form loss coefficients. hence, uncertainty and sensitivity measures were applied to find out which parameter is more relevant for the overall pressure drop. In the frame of this investigation, the system code TRACE and the software system for uncertainty and sensitivity, SUSA, were used. The results show that the total pressure drop varies between -30 and ＋15% related to the reference case.

关键词： Trace SUSA LACANES hELIOS pressure drop friction lead-bismuth-eutectics.

Detecting accidental punctures and lacerations during cholecystectomy in large datasets: Two methods of analysis

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hepatobiliary & Pancreatic Diseases International 2018年第5期17卷 430-436页

作者： Artem Shmelev Anne M Sill Gopal C Kowdley Juan A sanchez Steven C Cunningham Department of Surgery Saint Agnes Hospital and Cancer Center

Background: After the Institute of Medicine(IOM) report To Err Is human highlighted the impact of medical errors, the Agency for healthcare Research and Quality(AhRQ) developed Patient-Safety Indicators(PSI) to improve quality by identifying potential inpatient safety problems. PSI-15 was created to study accidental punctures and lacerations(APL), but PSI-15 may underestimate APLs in populations of patients. This study compares PSI-15 with a more inclusive approach using a novel composite of secondary diagnostic and procedural codes. Methods: We used Nationwide Inpatient Sample(NIS) data(20 0 0–2012) from AhRQ’s healthcare Cost and Utilization Project(h-CUP). We analyzed PSI-15-positive and-negative cholecystectomies. Cross tabulations identified codes that were significantly more frequent among PSI-15-positive cases; these secondary diagnostic and procedural codes were selected as candidate members of a composite marker(CM) of APL. We chose cholecystectomy patients for study because this is one of the most common general operations, and the large size of NIS allows for meaningful analysis of infrequent occurrences such as APL rates. Results: CM identified 1.13 times more APLs than did PSI-15. Patients with CM-detected APLs were significantly older and had worse mortality, comorbidities, lengths of stay, and charges than those detected with PSI-15. Further comparison of these two approaches revealed that time-series analysis for both APL markers revealed parallel trends, with inflections in 2007, and lowest APL rates in July. Conclusions: Although CM may yield more false positives, it appears more inclusive, identifying more clinically significant APLs, than PSI-15. Both measures presented similar trends over time, arguing against inflation in PSI-15 reporting. While arguably less specific, CM may increase sensitivity for detecting APL events during cholecystectomies. These results may inform the interpretation of other large population studies of APLs following abd

关键词： Cholecystectomy Patient safety Accidental lacerations AhRQ PSI-15

Advanced Asymmetrical Supercapacitors Based on Graphene hybrid Materials

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Nano Research 2011年第8期4卷 729-736页

作者： hailiang Wang Yongye Liang Tissaphern Mirfakhrai Zhuo Chen hernan sanchez Casalongue hongjie Dai Department of Chemistry Stanford University Stanford CA 94305 USA

Supercapacitors operating in aqueous solutions are low cost energy storage devices with high cycling stability and fast charging and discharging capabilities, but generally suffer from low energy densities. here, we grow Ni（Oh）2 nanoplates and RuO2 nanoparticles on high quality graphene sheets in order to maximize the specific capacitances of these materials. We then pair up a Ni（Oh）2/graphene electrode with a RuO2/graphene electrode to afford a high performance asymmetrical supercapacitor with high energy and power density operating in aqueous solutions at a voltage of -1.5 V. The asymmetrical supercapacitor exhibits significantly higher energy densities than symmetrical RuO2-RuO2 supercapacitors or asymmetrical supercapacitors based on either RuO2- carbon or Ni（Oh）2-carbon electrode pairs. A high energy density of -48 W.h/kg at a power density of -0.23 kW/kg, and a high power density of -21 kW/kg at an energy density of N14 W-h/kg have been achieved with our Ni（Oh）2/graphene and RuO2/graphene asymmetrical supercapacitor. Thus, pairing up metal-oxide/graphene and metal-hydroxide/graphene hybrid materials for asymmetrical supercapacitors represents a new approach to high performance energy storage.

关键词： Asymmetrical supercapacitor graphene Ni(Oh)2 RuO2 hybrid nanomaterials energy storage