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Science China(Technological Sciences) 2010年第1期53卷 264-271页

作者： WANG KateNing viola birss College of Chemistry South China University of Technology Department of Chemistry University of CalgaryCalgary T2N1N4Canada

Highly dispersed,high performance Pt and PtRu catalysts,supported on multiwalled carbon nanotubes(CNTs),were prepared by a high pressure organic colloid *** particle sizes of the active components were as small as 1.2 nm for Pt and 1.1 nm for PtRu,and the active Pt surface areas were 295 and 395 m2/g,*** catalysts showed very high activities toward the anodic oxidation of methanol,evaluated by cyclic voltammetry,being up to 4 times higher than that of commercial Johnson Matthey Hispec 2000 Pt/XC-72R and 5 times better than Hispec 5000 PtRu/XC-72R *** a full air/hydrogen fuel cell,a membrane-electrode assembly prepared using our Pt/CNT and PtRu/CNT catalysts showed 50% and 100% higher performances than those prepared with commercial Johnson Matthey Pt/XC-72R and PtRu/XC-72R catalysts for the same Pt loading and operating conditions.

关键词： direct methanol fuel cell hydrogen fuel cells anodes catalysts methanol oxidation carbon nanotubes organic colloidal method

On the electrophysiology of the atrial fast conduction system:an uncertain quantification study

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Acta Mechanica Sinica 2021年第2期37卷 264-278页

作者： Giulio Del Corso Roberto Verzicco Francesco viola GSSI(Gran Sasso Science Institute) L'AquilaItaly University of Roma Tor Vergata RomeItaly POF Group University of TwenteEnschedeThe Netherlands

Cardiac modeling entails the epistemic uncertainty of the input parameters,such as bundles and chambers geometry,electrical conductivities and cell parameters,thus calling for an uncertainty quantification(UQ)*** the cardiac activation and the subsequent muscular contraction is provided by a complex electrophysiology system made of interconnected conductive media,we focus here on the fast conductivity structures of the atria(internodal pathways)with the aim of identifying which of the uncertain inputs mostly influence the propagation of the depolarization ***,the distributions of the input parameters are calibrated using data available from the literature taking into account gender *** output quantities of interest(Qols)of medical relevance are defined and a set of metamodels(one for each Qol)is then trained according to a polynomial chaos expansion(PCE)in order to run a global sensitivity analysis with non-linear variance-based SoboF indices with confidence intervals evaluated through the bootstrap *** most sensitive parameters on each Qol are then identified for both genders showing the same order of importance of the model inputs on the electrical ***,the probability distributions of the Qols are obtained through a forward sensitivity analysis using the same trained *** results that several input parameters-including the position of the internodal pathways and the electrical impulse applied at the sinoatrial node一have a little influence on the Qols ***-versa the electrical activation of the atrial fast conduction system is sensitive on the bundles geometry and electrical conductivities that need to be carefully measured or calibrated in order for the electrophysiology model to be accurate and predictive.

关键词： Uncertainty quantification Global sensitivity analysis Forward analysis Atrial modelling Electrophysiology Monodomain model

Design and Robust Performance Evaluation of a Fractional Order PID Controller Applied to a DC Motor

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 304-314页

作者： J.viola L.Angel J.M.Sebastian Universidad Pontificia Bolivariana Universidad Politecnica de Madrid Centre for Automation and Robotics (CAR) UPM-CSIC

This paper proposes a methodology for the quantitative robustness evaluation of PID controllers employed in a DC motor. The robustness analysis is performed employing a 2~3 factorial experimental design for a fractional order proportional integral and derivative controller(FOPID), integer order proportional integral and derivative controller(IOPID)and the Skogestad internal model control controller(SIMC). The factors assumed in experiment are the presence of random noise,external disturbances in the system input and variable load. As output variables, the experimental design employs the system step response and the controller action. Practical implementation of FOPID and IOPID controllers uses the MATLAB stateflow toolbox and a NI data acquisition system. Results of the robustness analysis show that the FOPID controller has a better performance and robust stability against the experiment factors.

关键词： Factorial experimental design fractional-order PID controller robustness analysis SIMC PID controller

Metabolic Control of Chloroplast Gene Expression： An Emerging Theme

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Molecular Plant 2017年第1期10卷 1-3页

作者： Alexandra-viola Bohne J?rg Nickelsen Department Biology I Molecular Plant Sciences LMU Munich Grosshaderner Strasse 2-4 82152 Planegg-Martinsried Germany

In all organisms, regulation of gene expression plays an essential part in acclimation to changes in the environment and the meta-bolic status of cells. However, little is known about the mecha-nisms by which nutritio... 详细信息

关键词： Control Expression Theme

Preparation of high dispersion and high performance PtRu/CNTs catalyst by an organic colloid method

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电池 2006年第5期36卷 371-374页

作者：王宁卡特刘军民廖世军 V.birss 华南理工大学化学科学学院 Depart ment of Chemistry Universityof CalgaryCalgaryCanada

A high dispersion and high performance PtRu catalyst supported on carbon nanotubes was prepared by an organic colloid method. The particle size of the active components could be as small as 1.0 nm,the active surface area was about 466 m2/g(Pt). The catalytic activity toward anodic oxidation of methanol was about 3 ～ 4 times higher than that of Johnson Matthey PtRu/XC-72R catalyst. The single testing showed that the performance of the prepared catalyst was higher than that of the commercial one.

关键词： PtRu/CNTs organic colloidal method direct methanol fuel cell(DMFC)

Electrochemiluminescence immunoassay method underestimates cortisol suppression in ulcerative colitis patients treated with oral prednisone

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World Journal of Gastroenterology 2014年第31期20卷 10895-10899页

作者： Francesco Manguso Raffaele Bennato Giovanni Lombardi Assunta viola Elisabetta Riccio Livio Cipolletta Division of Gastroenterology Cardarelli Hospital Division of Haematology and Stem Cell Transplantation Unit Cardarelli Hospital

AIM: To evaluate cortisolemia by using conventional electrochemiluminescence immunoassay (ECLIA) method compared to liquid chromatography-tandem mass spectrometry (LC-MS/MS) method in active ulcerative colitis (UC) pa... 详细信息

关键词： Cortisol Immunoassay Liquid chromatography Prednisone Tandem mass spectrometry Ulcerative colitis

Phytochemicals, polyphenols content, in vitro antioxidant and antibacterial activities of Albizia coriaria Welw ex. Oliver flowers

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Traditional Medicine Research 2023年第2期8卷 1-6页

作者： Timothy Omara Ambrose K.Kiprop viola J.Kosgei Department of Chemistry and Biochemistry School of Sciences and Aerospace StudiesMoi UniversityP.O.Box 3900-30100EldoretKenya Africa Center of Excellence II in Phytochemicals Textile and Renewable Energy(ACE II PTRE)Moi UniversityP.O.Box 3900-30100EldoretKenya Institute of Chemistry of Renewable Resources Department of ChemistryUniversity of Natural Resources and Life Sciences Vienna3430TullnAustria Testing Department Uganda National Bureau of StandardsBweyogerere Industrial and Business ParkP.O.Box 6329KampalaUganda

Albizia coriaria Welw ***(hereafter ***)is a revered medicinal tree whose organs are used by indigenous African societies for managing various ***,we assessed the secondary metabolites,total polyphenolics,free radical scavenging and antimicrobial activities of *** *** dry powdered sample was extracted serially with ethyl acetate,ethanol and distilled *** of classical phytochemical screening showed that saponins,phenols,alkaloids,flavonoids,tannins and terpenes were the dominant *** highest total polyphenolic content(10.37±0.02 mg QE/g DW and 72.09±0.09 mg GAE/g DW)and free radical scavenging potential(IC50=24.23±0.04 mg/mL)were for the ethyl acetate *** also had a higher bacteriostatic activity than the ethanolic extract against Pseudomonas aeruginosa,Salmonella typhi,Escherichia coli and Staphylococcus aureus with diameters of inhibition ranging from 7.00±0.00 to 22.00±1.73 *** aqueous extract showed no appreciable antibacterial effect on the tested *** is the first report which support the use of floral extracts of this species in the management of ailments in African traditional medicine.

关键词： bacteriostatic Albizia coriaria DPPH assay traditional medicine oxidative stress

Magnetoelectric coupling at microwave frequencies observed in bismuth ferrite-based multiferroics at room temperature

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Journal of Materials Science & Technology 2023年第6期137卷 100-103页

作者： Man Zhang Vladimir Koval Yu Shi Yajun Yue Chenglong Jia Jiagang Wu Giuseppe viola Haixue Yan School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondon E14NSUK Institute of Materials Research Slovak Academy of SciencesWatsonova 47Kosice 04001Slovakia Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou 730000China Department of Chemistry Queen Mary University of LondonMile End RoadLondon E14NSUK Department of Materials Science Sichuan UniversityChengdu 610064China

***,In the search for advanced multifunctional materials for next generation sensors and logic devices,magnetoelectric multifer-roics exhibiting simultaneously ferromagnetism and ferroelectric-ity within the same phas... 详细信息

关键词： microwave coupling ferroelectric

Prevalence and risk factors of acute-on-chronic liver failure in a single center from Argentina

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World Journal of Hepatology 2016年第34期8卷 1529-1534页

作者： Cristian Dominguez Eugenia Romero Jorgelina Graciano Jose Luis Fernandez Luis viola Division of Gastroenterology Sanatorio Guemes Centro Integral de Gastroenterología

AIMTo study the prevalence, characteristics, risk factors and mortality at 28 d of acute-on-chronic liver failure (ACLF). METHODSA total of 100 cirrhotic patients admitted to our hospital for more than one day were included during the period between June 2013 and December 2015. We used the European Association for the Study of the Liver-Chronic Liver Failure-Consortium diagnostic criteria for ACLF, considering it as the acute decompensation of cirrhosis associated with the presence of one or more organ failure. For the diagnosis of organic failure the Chronic Liver Failure-Sequential Organ Failure Assessment score was used. Our population was divided into patients with and without ACLF. Clinical characteristics, presence of precipitating events, potential risk factors for developing ACLF and causes of mortality were analyzed. Mortality at 28 d was evaluated. RESULTSTwenty-nine patients (29%) developed ACLF criteria. Alcoholism, detected in 58 patients (58%), was the major etiological agent of cirrhosis. Bacterial infections were recognized as a precipitating event in 41.3% of cases and gastrointestinal bleeding in 27.5%. No precipitating event was identifiable in 27.5% of patients with ACLF. Comparing patients with and without ACLF, statistically significant risk factors were: Child Pugh score 10.2 ± 2.1 vs 8.4 ± 1.6 (P ˂ 0.0001), MELD score 20.7 ± 8.5 vs 12.3 ± 4 (P ˂ 0.0001), presence of ascites 27 (93%) vs 43 (60.5%) (P = 0.001), leukocytosis 15300 ± 8033 per cubic millimeter vs 10770 ± 5601 per cubic millimeter (P ˂ 0.0001), and high plasma levels of C reactive protein values 50.9 ± 46.4 mg/L vs 28.6 ± 23.4 mg/L (P ˂ 0.0019). Mortality rate was 62% (18 patients) vs 5.6% (4 patients), respectively (P CONCLUSIONWe observed that the ACLF is a frequent entity in this group of patients and has a significantly higher mortality rate.

关键词： Acute-on-chronic liver failure Acute liver decompensation Cirrhosis Ascites Mortality

Translation-A Process of Transformation

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教师 2008年第18期 72-73页

作者： viola Zhu Shanghai Commercial Accounting School Shanghai 200011

Translation is a process that involves transformation and reproduction. This essay discusses some useful techniques of trans-lating practice by introducing a simple model. A few examples of good translation are presen... 详细信息

关键词：英语教学方法翻译方法语法