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Investigating local corrosion processes of magnesium alloys with scanning probe electrochemical techniques: A review

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Journal of magnesium and Alloys 2022年第11期10卷 2997-3030页

作者： mara Cristina Lopes de oliveira Rejane maria Pereira da Silva Ricardo m.Souto Renato Altobelli Antunes Federal University of ABC Center for EngineeringModeling and Applied Social SciencesAv.Dos Estados500109210-580Santo AndréSP Brazil Instituto de Pesquisas Energéticas e Nucleares IPEN/CNENAv.Prof.Lineu Prestes2242São PauloBrazil Institute of material Science and Nanotechnology University of La LagunaP.O.Box 456La LagunaTenerife 38200Spain

The study of corrosion of magnesium and its alloys has emerged a hot topic in the applications of lightweight structural materials. The inherently high electrochemical activity of bare magnesium surfaces still lacks a convincing mechanism to describe the observed experimental characteristics, and it has prompted the development of various types of protective coatings with the aim of slowing metal dissolution. In recent years, new instruments and techniques have been developed to study with spatial resolution the local corrosion processes that occur in metallic materials in general, and for magnesium and its alloys in particular, both for bare surfaces and coated. Scanning microelectrochemical techniques, such as local electrochemical impedance spectroscopy(LEIS), scanning electrochemical microscopy(SECm), scanning vibrating electrode technique(SVET), scanning ion-selective electrode technique(SIET) and scanning Kelvin probe(SKP) can provide information about the local electrochemical activity of metallic surfaces. In the present work, the applications of these techniques in corrosion studies of magnesium and its alloys are reviewed. Assessment of corrosion mechanisms, barrier properties of conventional coatings and active corrosion behavior of self-healing coatings are examined. Limitations and future developments in this area are discussed.

关键词： magnesium alloys LEIS SECm SVET SIET SKP

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Spontaneous rupture of hepatic hemangiomas:A review of the literature

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World Journal of Hepatology 2010年第12期2卷 428-433页

作者： marcelo AF Ribeiro Francine Papaiordanou Juliana m Gonalves Eleazar Chaib Department of Surgery Medical SchoolUniversity of Santo Amaro Professor of Surgery at University Cidade de So Paulo Universidade Cidade de So Paulo medical Student at Universidade Cidade de So Paulo Liver and Portal Hypertension Surgery Clinicas HospitalUniversity of So Paulo Medical School Nuffield Department of Surgery Churchill HospitalUniversity of Oxford

Hepatic hemangiomas are congenital vascular malformations,considered the most common benign mesenchymal hepatic tumors,composed of masses of blood vessels that are atypical or irregular in arrangement and size. Hepatic hemangiomas can be divided into two major groups:capillary hemangiomas and cavernous hemangiomas These tumors most frequently affect females (80%) and adults in their fourth and fifth decades of life. most cases are asymptomatic although a few patients may present with a wide variety of clinical symptoms,with spontaneous or traumatic rupture being the most severe complication. In cases of spontaneous rupture,clinical manifestations consist of sudden abdominal pain,and anemia secondary to ahaemoperitoneum. Disseminated intravascular coagulopathy can also occur. Haemodynamic instability and signs of hypovolemic shock appear in about one third of cases. As the size of the hemangioma increases,so does the chance of rupture. Imaging studies used in the diagnosis of hepatic hemangiomas include ultrasonography,dynamic contrast-enchanced computed tomography scanning,magnetic resonance imaging,hepatic arteriography,digital subtraction angiography,and nuclear medicine studies. In most cases hepatic hemangiomas are asymptomatic and should be followed up by means of periodic radiological examination. Sur gery should be restricted to specific situations. Absolute indications for surgery are spontaneous or trau m atic rupture with hemoperitoneum,intratumoral blee ding and consumptive coagulopathy (Kassabach-merrit syndrome). In a patient presenting with acute abdo minal pain due to unknown abdominal disease,sponta neous rupture of a hepatic tumor such as a hemangio ma should be considered as a rare differential diagnosis.

关键词： Hepatic hemangioma Giant hepatic hemangioma Liver tumor Spontaneous rupture Surgery

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Assessment of alterability of basalt used for riprap by petrographic examination

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Journal of Rock mechanics and Geotechnical Engineering 2019年第1期11卷 208-213页

作者： maria Heloisa Barros de oliveira Frascá mHB Geological Services

All engineering projects consist of several steps, and one of the main tasks is to identify and characterize the most important features of rock types that will be excavated, crushed, or mined for any particular usage purpose, from a single residential building to major works of infrastructure. Laboratory investigation on engineering geology is thus conducted in order to determine the most relevant rock properties when designing structures such as mining shafts, tunnels, buildings, or reservoir dams to be built in sites associated with rocks. A wide range of laboratory tests is available, making the correct choice of test methods greatly relevant to determine the key property for the planned use of the rock. This paper is an illustrative case of laboratory testing of basaltic rocks to be used as riprap in a reservoir dam. It shows the important role of the petrographic study carried out to analyze the distribution pattern of smectite clay minerals. Test results are explained for the assessment of rock alterability, an essential aspect for the selection of the most suitable basalt variety for the envisaged conditions of use.

关键词： Rock properties Laboratory testing Test methods Petrographic analysis Smectite clay minerals Basaltic rocks Accelerated weathering tests Alterability

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ASYmPTOTIC HOmOGENIZATION IN A PARABOLIC SEmILINEAR PROBLEm WITH PERIODIC COEFFICIENTS AND INTEGRABLE INITIAL DATA

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Acta mathematica Scientia 2013年第5期33卷 1275-1292页

作者： Rogerio Luiz Quintino de oliveira JUNIOR Instituto de matema'tica e Estat' stica Universidade do Estado do R.de Janeiro Rua S ao Francisco Xavier524 - Pavilha o Reitor Joa o Lyra Filho 6oandar bl.B 20559-900 Rio de Janeiro R.J. Brazil

In this paper, we study the large time behavior of solutions of the parabolic semilinear equation δtu-div（a（x）△↓u） = -｜u｜^αu in （0,∞） × R^N, where α 〉 0 is constant and a∈ Cb^1（R^N） is a symmetric periodic matrix satisfying some ellipticity *** an integrable initial data u0 and α ∈ （2/N, 3/N）, we prove that the large time behavior of solutions is given by the solution U（t, x） of the homogenized linear problem δtU-div（a^h△↓U）=0,U（0） = C, where a^h is the homogenized matrix of a（x）, C is a positive constant and δ is the Dirac measure at 0.

关键词： homogenization similinear parabolic equation integrable initial data matrix with periodic coefficient large time behavior

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Physicochemical characterization, the Hirshfeld surface, and biological evaluation of two meloxicam compounding pharmacy samples

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Journal of Pharmaceutical Analysis 2018年第2期8卷 103-108页

作者： Luciana F.A.Romani maria I.Yoshida Elionai C.L.Gomes Renes R.machado Felipe F.Rodrigues marcio m.Coelho marcelo A.oliveira maria B.Freitas-marques Rosane A.S.San Gil Wagner N.mussel Department of Chemistry Institute of Exact Sciences Federal University of Minas Gerais Department of Pharmaceutical Products Faculty of Pharmacy Federal University of Minas Gerais Health Science Department Federal University of Espírito Santo Campus Sao Mateus Institute of Chemistry Federal University of Rio de Janeiro Campus Fundao

meloxicam(mLX) is an anti-inflammatory drug susceptible to variations and crystalline transitions. In compounding pharmacies, the complete crystallographic evaluation of the raw material is not a routine procedure. We performed a complete crystallographic characterization of aleatory raw mLX samples from compounding pharmacies. X-ray diffraction indicated the presence of two crystalline forms in one sample. DSC experiments suggested that crystallization, or a crystal transition, occurred differently between samples. The FTIR and ~1H NmR spectra showed characteristic assignments.^(13)C solid-state NmR spectroscopy indicated the presence of more than one phase in a sample from pharmacy B. The Hirshfeld surface analysis, with electrostatic potential projection, allowed complete assignment of the UV spectra in ethanol solution. The polymorph I of meloxicam was more active than polymorph III in an experimental model of acute inflammation in mice. Our results highlighted the need for complete crystallographic characterization and the separation of freely used raw materials in compounding pharmacies,as a routine procedure, to ensure the desired dose/effect.

关键词： meloxicam Polymorphism Hirshfeld surface Anti-inflammatory activity

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A comparative study of semi-active control strategies for base isolated buildings

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Earthquake Engineering and Engineering Vibration 2015年第3期14卷 487-502页

作者： oliveira F. morais P. Suleman A. National Laboratory for Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Scholarship HolderPh D CandidateMSc National Laboratory for Civil Engineering (LNEC) Av. do Brasil 101 1700-066 Lisbon Portugal Researcher Ph D University of Victoria Dep. Mechanical Engineering PO Box 1700 Stn CSC Victoria BC V8W 2Y2 Canada Professor Ph D PEng

A comparative analytical study of several control strategies for semi-active(SA) devices installed in baseisolated buildings aiming to reduce earthquake induced vibrations is *** force tracking schemes comprising a linear controller plus a 'clipped' algorithm and a nonlinear output feedback controller(NOFC) are considered to tackle this *** controllers include the integral controller(I),the linear quadratic regulator(LQR) and the model predictive controller(mPC).A single degree-of-freedom system subjected to input accelerograms representative of the Portuguese seismic actions are first used to validate and evaluate the feasibility of these *** obtained results show that structural systems using SA devices can in general outperform those equipped with passive devices for lower fundamental frequency structural systems,namely base-isolated *** effectiveness of the proposed strategies is also evaluated on a 10 storey base-isolated dual frame-wall *** force tracking scheme with an integral controller outperforms the other three as well as the original structure and the structure equipped with passive devices.

关键词： semi-active control integral controller linear qua

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Evaluation of the effectiveness of horizontal subsurface flow constructed wetlands for different media

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Journal of Environmental Sciences 2010年第6期22卷 820-825页

作者： Antonio Albuquerque José oliveira Sabrina Semitela Leonor Amaral Department of Civil Engineering and Architecture and C-mADE University of Beira Interior municipality of Penamacor Department of Sciences and Environmental Engineering Faculty of Sciences and TechnologyNew University of Lisbon

Two media bed （gravel and Filtralite NR） were tested in a mesocosm to evaluate the removal of organic matter （as chemical oxygen demand （COD））, ammonia （NH4-N）, nitrite, nitrate and solid matter （as total suspended solids （TSS）） for a synthetic wastewater （acetate-based） and a domestic wastewater. The use of Filtralite allowed average removal rates （6--16.8 g COD/（m^2·day）, 0.8-1.1 g NH4-N/（m^2·day） and 3.1 g TSS/（m^2·day）） and removal efficiencies （65%-93%, 57%-85% and 78% for COD, NH4-N and TSS, respectively）, higher than that observed in the experiments with gravel. The applied loads of COD, ammonia, nitrate and TSS seem to influence the respective removal rates but only for the treatment of domestic wastewater with nigher correlation coefficients for Filtralite. Regardless the type of media bed and the type of wastewater, nitrate was completely removed for nitrogen loading rates up to 1.3 g NO3-N/（m^2·day）. There was no evidence of the influence of nitrate loads on the removal of organic matter.

关键词： media bed constructed wetlands pollutants removal rates

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multimodal brain monitoring in fulminant hepatic failure

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World Journal of Hepatology 2016年第22期8卷 915-923页

作者： Fernando mendes Paschoal Jr Ricardo Carvalho Nogueira Karla De Almeida Lins Ronconi marcelo de Lima oliveira manoel Jacobsen Teixeira Edson Bor-Seng-Shu Laboratory for Neurosonology and Cerebral Hemodynamics Department of Neurology Hospital das Clinicas Sao Paulo University Medical School Department of Neurology Division of Neurosurgery Hospital das Clinicas Sao Paulo University Medical School

Acute liver failure, also known as fulminant hepatic failure(FHF), embraces a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction, and hepatic encephalopathy. Cerebral edema and intracranial hypertension are common causes of mortality in patients with FHF. The management of patients who present acute liver failure starts with determining the cause and an initial evaluation of prognosis. Regardless of whether or not patients are listed for liver transplantation, they should still be monitored for recovery, death, or transplantation. In the past, neuromonitoring was restricted to serial clinical neurologic examination and, in some cases, intracranial pressure monitoring. Over the years, this monitoring has proven insufficient, as brain abnormalities were detected at late and irreversible stages. The need for real-time monitoring of brain functions to favor prompt treatment and avert irreversible brain injuries led to the concepts of multimodal monitoring and neurophysiological decision support. New monitoring techniques, such as brain tissue oxygen tension, continuous electroencephalogram, transcranial Doppler, and cerebral microdialysis, have been developed. These techniques enable early diagnosis of brain hemodynamic, electrical, and biochemical changes, allow brain anatomical and physiological monitoring-guided therapy, and have improved patient survival rates. The purpose of this review is to discuss the multimodality methods available for monitoring patients with FHF in the neurocritical care setting.

关键词： Fulminant hepatic failure Cerebral edema multimodality methods Intracranial hypertension Liver transplantation

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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 123-138页

作者： Chentong GAO Huiyu SUN Jianping GU W.m.HUANG College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics School of mechanical and Aerospace Engineering Nanyang Technological University Jiangsu Key Laboratory of Advanced Structural materials and Application Technology School of Materials Science and EngineeringNanjing Institute of Technology

Currently, there are a limited number of dynamic models available for braided composite plates with large overall motions, despite the incorporation of three-dimensional(3D) braided composites into rotating blade components. In this paper, a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established. Based on Kirchhoff's plate assumptions, the displacement variables of the plate are expressed. By incorporating the braiding directions into the constitutive equation of the braided composites, the dynamic model of the plate considering braiding directions is obtained. The effects of the speeds, braiding directions, and braided angles on the responses of the plate with fixed-axis rotation and translational motion, respectively, are investigated. This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions. It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications.

关键词： Constitutive equations

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One image is worth more than a thousand words:producing an atlas of medical signs for teaching clinical and forensic toxicology

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Forensic Sciences Research 2022年第4期7卷 815-822页

作者： Ricardo Jorge Dinis-oliveira TOXRUN-Toxicology Research Unit University Institute of Health SciencesAdvanced Polytechnic and University Cooperative(CESPU)CRLGandraPortugal Department of Public Health and Forensic Sciences and Medical EducationFaculty of MedicineUniversity of PortoPortoPortugal UCIBIO-REQUImTE Laboratory of ToxicologyDepartment of Biological SciencesFaculty of PharmacyUniversity of PortoPortoPortugal

Clinical and forensic toxicology are critically involved in the acquisition of basic skills to correctly suspect intoxication,collect biological and non-biological materials for toxicological analysis,comprehend the complexities inherent to laboratory activity,and understand the fundamentals of toxicokinetics and toxicodynamics that underlie the interpretation of *** works presents a pedagogical innovation proposal for the teaching of clinical and forensic toxicology based on a compilation of more than 3000 cases where the image was fulcra for *** experience in this article follows the model practiced in bachelors,masters,and PhD degrees,as well as in other continuing training courses,where we are teaching toxicology for more than 15 *** these levels of education are considered fundamental to the sound development of this *** approach aims also to offer strength to the intervention of the true toxicologist in all the toxicological phases,besides the classic analytical ***,it is impossible to provide effective clinical and forensic toxicological interpretations without a proper and broad education,and not thinking exclusively in terms of laboratory *** the future,it will be interesting to evaluate knowledge retention and to propose a database of videos of signs related to intoxications.

关键词： Forensic sciences clinical and forensic toxicology teaching learning signs of exposure pre-analytical phase

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