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Global multiplicity of solutions to a defocusing quasilinear Schrodinger equation with the singular term

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Science China Mathematics 2023年第8期66卷 1789-1812页

作者： Siyu Chen Carlos alberto Santos Minbo Yang Jiazheng Zhou Department of Mathematics Zhejiang Normal UniversityJinhua 321004China Departamento de Matematica Universidade de BrasiliaBraslia 70910-900Brazil

We consider a class of modified quasilinear Schrodinger equations-△u+k/2u△u^(2)=λα(x)u^(-α)+b(x)u^(β) in Ω with u(x)=0 on■Ω,where Ω■R^(N)is a bounded domain with a regular boundary,N≥3,a and b are bounded mensurable functions,0<α<1<β<2*-1 and k,λ≥0 are two parameters.We establish the global existence and multiplicity results of positive solutions in H^(1)_(0)(Ω)∩L^(∞)(Ω)for appropriate classes of parameters k andλand coefficients a(x)and b(x).

关键词： quasilinear Schrodinger equation singular term square diffusion term

Nanofluid based on 1-dodecylpyridinium chloride for enhanced oil recovery

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Petroleum Science 2023年第1期20卷 600-610页

作者： Akram Al-Asadi Alba Somoza alberto Arce Eva Rodil Ana Soto CRETUS.Department of Chemical Engineering Universidade de Santiago de CompostelaE-15782Santiago de CompostelaSpain Chemical and Petrochemical Techniques Eng.Department Basra Engineering Technical CollegeSothern Technical UniversityMinistry of Higher Education and Scientific ResearchIraq School of Engineering Universidade de A CorunaE-15403FerrolSpain

The use of nanoparticles is considered promising for enhanced oil recovery(EOR),especially when they are combined with surfactants.However,the combination of nano-sized material with surface-active ionic liquids(SAILs)is an unexplored EOR method.In this work,the advantages of mixing Al2O3 nanoparticles with the SAIL 1-dodecylpyridinium chloride were investigated.Stable nanofluids in brine could only be achieved using the polymer polyvinylpyrrolidone(PVP)as a stabilizing agent.It was found that the addition of nanoparticles(and PVP)to the surfactant formulation helped to:slightly increase its viscosity,enhance its water-oil interfacial tension(IFT)reduction capacity,and reduce the adsorption on carbonate rocks(adsorption on sandstone was found to be excessive).IFT was selected as target property to minimize for the design of EOR formulations.Core flooding tests were carried out with surfactant(0.5 wt%[C_(12)py]Cl),surfactant-polymer(0.5 wt%[C_(12)py]Cl,1.0 wt%PVP)and nanofluid(0.05 wt%Al_(2)O_(3),1.0 wt%PVP,0.5 wt%[C12py]Cl)formulations in brine(0.5 wt%NaCl).Additional oil recoveries of 3.4%,7.4%and 12.0%OOIP were achieved,respectively,the nanofluid formulation being the most promising for the application.Moreover,it was found capable of changing the wettability of carbonate rocks from oilwet to intermediate-wet.The significance of this work lies in showing the new possibilities resulting from the combination of SAILs and nanoparticles for EOR,specifically the combination of[C_(12)py]Cl with Al_(2)O_(3).

关键词： Nanofluid Viscosity Interfacial tension Adsorption Wettability EOR

New insights for the catalytic oxidation of cyclohexane to K-A oil

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Journal of Energy Chemistry 2022年第7期31卷 45-51,I0002页

作者： Alessandro Vomeri Marta Stucchi alberto Villa Claudio Evangelisti rea Beck Laura Prati Dipartimento di Chimica Universitàdegli Studi di MilanoVia Golgi 1920133MilanoItaly CNR-ICCOM-Istituto di Chimica dei Composti Organo Metallici Via G.Moruzzi 1I-56124 PisaItaly Centre for Energy Research Surface Chemistry and Catalysis DepartmentP.O.Box 49H-1525 BudapestHungary

Au-based catalysts have been reported to be active in the cyclohexane oxidation to K-A oil, but they showed some limitiations in terms of productivity, selectivity and required reaction conditions. The possibility to overcome some of these limits has been explored coupling Au with Cu, which can be suitable for undergoing the electron-switch in the initial step of the cyclohexane oxidation. Hence, a bimetallic 2 wt% Au Cu/Al_(2)O_(3) catalyst was tested in the oxidation of cyclohexane, working at mild conditions of 120 ℃ and 4 bar of O_(2). The combination of the catalyst with a very small amount of benzaldehyde used as cheaper and non-toxic radical initiator allowed to obtain a very high productivity of cyclohexanol and cyclohexanone(45 mmol*m L/mgmet*h) with a selectivity of 94%. Moreover, comparing the catalysed reaction with the non-catalysed one, the role of the catalyst has been disclosed.

关键词： K-A oil Cyclohexane oxidation Benzaldehyde Radical initiator Heterogeneous catalysis Radical mechanism AuCu bimetallic catalyst

Three-dimensional single particle tracking using 4π self-interference of temporally phase-shifted fluorescence

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Light(Science & Applications) 2023年第3期12卷 415-424页

作者： Leanne Maurice alberto Bilenca Biomedical Engineering Department Ben-Gurion University of the Negev1 Ben Gurion BlvdBe’er-Sheva84105Israel Ilse Katz Institute for Nanoscale Science and Technology Ben-Gurion University of the Negev1 Ben Gurion BlvdBe’er-Sheva84105Israel

Single particle tracking in three dimensions is an indispensable tool for studying dynamic processes in various disciplines,including material sciences,physics,and biology,but often shows anisotropic three-dimensional spatial localization precision,which restricts the tracking precision,and/or a limited number of particles that can be tracked simultaneously over extended volumes.Here we developed an interferometric,three-dimensional fluorescence single particle tracking method based on conventional widefield excitation and temporal phase-shift interference of the emitted,high-aperture-angle,fluorescence wavefronts in a greatly simplified,free-running,triangle interferometer that enables tracking of multiple particles at the same time with<10-nm spatial localization precision in all three dimensions over extended volumes(~35×35×2μm^(3))at video rate(25 Hz).We applied our method to characterize the microenvironment of living cells and up to~40μm deep in soft materials.

关键词： materials particle dimensions

Time-domain terahertz spectroscopy in high magnetic fields

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Frontiers of Optoelectronics 2021年第1期14卷 110-129页

作者： Andrey BAYDIN Takuma MAKIHARA Nicolas marquez PERACA Junichiro KONO Department of Electrical and Computer Engineering Rice UniversityHoustonTX 70005USA Department of Physics and Astronomy Rice UniversityHoustonTexas 77005USA Department of Materials Science and NanoEngineering Rice UniversityHoustonTexas 77005USA

There are a variety of elementary and collective terahertz-frequency excitations in condensed matter whose magnetic field dependence contains significant insight into the states and dynamics of the electrons involved.Often,determining the frequency,temperature,and magnetic field dependence of the optical conductivity tensor,especially in high magnetic fields,can clarify the microscopic physics behind complex many-body behaviors of solids.While there are advanced terahertz spectroscopy techniques as well as high magnetic field generation techniques available,a combination of the two has only been realized relatively recently.Here,we review the current state of terahertz time-domain spectroscopy(THz-TDS)experiments in high magnetic fields.We start with an overview of time-domain terahertz detection schemes with a special focus on how they have been incorporated into optically accessible high-field magnets.Advantages and disadvantages of different types of magnets in performing THz-TDS experiments are also discussed.Finally,we highlight some of the new fascinating physical phenomena that have been revealed by THz-TDS in high magnetic fields.

关键词： high magnetic field terahertz time-domain spectroscopy(THz-TDS)

A Tabu-search-based Algorithm for Distribution Network Restoration to Improve Reliability and Resiliency

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 302-311页

作者： Alessandro Bosisio alberto Berizzi Daniele Lupis Andrea Morotti Gaetano Iannarelli Bartolomeo Greco Energy Department of Politecnico di Milano MilanItaly E-distribuzione MonzaItaly Unareti Electrical Network Planning Department MilanItaly Department of Astronautics Electrical and Energy Engineering of the Sapienza UniversityRomeItaly Technological Development Department of the DSO Unareti MilanItaly Unareti Market Development and Special Projects Department MilanItaly IEEE

Fault restoration techniques have always been crucial for distribution system operators(DSOs).In the last decade,it started to gain more and more importance due to the introduction of output-based regulations where DSO performances are evaluated according to frequency and duration of energy supply interruptions.The paper presents a tabu-searchbased algorithm able to assist distribution network operational engineers in identifying solutions to restore the energy supply after permanent faults.According to the network property,two objective functions are considered to optimize either reliability or resiliency.The mathematical formulation includes the traditional feeders,number of switching operation limit,and radiality constraints.Thanks to the DSO of Milan,Unareti,the proposed algorithm has been tested on a real distribution network to investigate its effectiveness.

关键词： Distribution system operators(DSOs) heuristic algorithms power system reliability power system restoration resiliency

Twenty-four hours intraocular pressure in keratoconic eyes assessed by applanation tonometry and Tono-Pen AVIA

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International Journal of Ophthalmology(English edition) 2022年第1期15卷 52-58页

作者： Rafael Vidal Merola Sebastião Cronemberger Artur William Veloso alberto Diniz-Filho Nassim Calixto Glaucoma Service of São Geraldo Eye Hospital Clinic HospitalFederal University of Minas GeraisBelo HorizonteBelo Horizonte 30130-100State of Minas GeraisBrazil

AIM:To assess intraocular pressure(IOP)during the daily curve of intraocular pressure(DCPo)in keratoconic eyes and compare Goldmann applanation tonometer(GAT),without and with astigmatism correction(n GAT and c GAT)and Tono-Pen AVIA(TPA)assessment methods.METHODS:Thirty-nine keratoconic eyes of 24 patients were assessed.DCPo was evaluated with five IOP measurements;four were performed with a GAT(n GAT and c GAT),and a Tono-Pen AVIA(TPA)at various times throughout the day.RESULTS:Mean IOP DCPo values(mm Hg)were:n GAT,9.9±2.6;c GAT,11.3±2.6;TPA 12.3±3.1.Mean IOP DCPo differences(mm Hg)and Spearman’s correlation coefficients were as follows:c GATc-n GAT,1.32±1.31,r_(s)=0.879(Pc GAT>n GAT.IOP TPA measures are predictive of c GAT values,adjusted according to anterior chamber depth and corneal astigmatism.

关键词： intraocular pressure keratoconus tonometry

Current guidelines for the management of celiac disease:A systematic review with comparative analysis

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World Journal of Gastroenterology 2022年第1期28卷 154-175页

作者： alberto Raiteri Alessandro Granito Alice Giamperoli Teresa Catenaro Giulia Negrini Francesco Tovoli Division of Internal Medicine Hepatobiliary and Immunoallergic DiseasesIRCCS Azienda Ospedaliero-Universitaria di BolognaBologna 40138Italy

BACKGROUND Wheat and other gluten-containing grains are widely consumed,providing approximately 50%of the caloric intake in both industrialised and developing countries.The widespread diffusion of gluten-containing diets has rapidly led to a sharp increase in celiac disease prevalence.This condition was thought to be very rare outside Europe and relatively ignored by health professionals and the global media.However,in recent years,the discovery of important diagnostic and pathogenic milestones has led to the emergence of celiac disease(CD)from obscurity to global prominence.These modifications have prompted experts worldwide to identify effective strategies for the diagnosis and follow-up of CD.Different scientific societies,mainly from Europe and America,have proposed guidelines based on CD's most recent evidence.AIM To identify the most recent scientific guidelines on CD,aiming to find and critically analyse the main differences.METHODS We performed a database search on PubMed selecting papers published between January 2010 and January 2021 in the English language.PubMed was lastly accessed on 1 March 2021.RESULTS We distinguished guidelines from 7 different scientific societies whose reputation is worldwide recognized and representative of the clinical practice in different geographical regions.Differences were noted in the possibility of a no-biopsy diagnosis,HLA testing,follow-up protocols,and procedures.CONCLUSION We found a relatively high concordance between the guidelines for CD.Important modifications have occurred in the last years,especially about the possibility of a no-biopsy diagnosis in children.Other modifications are expected in the next future and will probably involve the extension of the non-invasive diagnosis to the adult population and the follow-up modalities.

关键词： Celiac disease Gluten Gluten-free diet Gluten sensitivity Clinical guidelines Non-invasive diagnosis Histopathological findings Serological markers Genetics

A computer vision system for early detection of anthracnose in sugar mango(Mangifera indica)based on UV-A illumination

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Information Processing in Agriculture 2023年第2期10卷 204-215页

作者： Leonardo Ramırez alberto Carlos Eduardo Cabrera Ardila Flavio Augusto Prieto Ortiz Facultad de Ingenierı´a Universidad Nacional de ColombiaBogota´D.C.111321Colombia

The present work describes the development of a computer vision system for the early detection of anthracnose in sugar mango based on Ultraviolet A illumination(UV-A).Anthracnose,a disease caused by the fungus Colletotrichum sp,is commonly found in the fruit of sugar mango(Mangifera indica).It manifests as surface defects including black spots and is responsible for reducing the quality of the fruit.Consequently,it decreases its commercial value.In more detail,this study poses a system that begins with image acquisition under white and ultraviolet illumination.Furthermore,it proposes to analyze the Red,Green and Blue color information(R,G,B)of the pixels under two types of illumination,using four different methods:RGB-threshold,RGB-Linear Discriminant Analysis(RGBLDA),UV-LDA,and UV-threshold.This analysis produces an early semantic segmentation of healthy and diseased areas of the mango image.The results showed that the combination of the linear discriminant analysis(LDA)and UV-A light(called UV-LDA method)in sugar mango images allows early detection of anthracnose.Particularly,this method achieves the identification of the disease one day earlier than by an expert with respect to the scale of anthracnose severity implemented in this work.

关键词： Sugar mango Anthracnose LDA UV-A light Grading Image processing