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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 1-8页

作者： Vidal Felix Navarro Torres Carlos Dinis da Gama matilde costa e silva Paula Falcao Neves Qiang Xie Mining and Geo-resources engineering Department of IST Technical University of Lisbon 1049-001 Portugal Faculty of Civil engineering Chongqing University Chongqing 400045 China

The stability and productivity concerning a modification on the traditional room and pillar for a new selective technique at the Portuguese Panasqueira Mine have been *** traditional room-and-pillar stoping uses 5.0-m wide rooms with 3.0 m×3.0 m pillars,while the selective room-and-pillar mining technique consists in stoping with rooms of 4.0 m wide and pillars of 4 m×4 m with a subsequent selective cutting of the quartz veins at the mid pillar of approximately 0.5 m high,to obtain a pillar section with an area of 3.0 m×3.0 *** stability and productivity analyses indicate that the selective technique obtains smaller average pillar safety factor,more rock mass displacement,more extraction and selectivity ratios,and ore grade improvement,compared with the traditional *** results show that the selective technique is also more *** proposed selective room-and-pillar mining technique is applicable to any sub-horizontal narrow quartz veins with wolfram,gold,*** as the famous La Rinconada gold mine in the Peruvian Andes.

关键词： mines and mining tungsten deposits productivity stability stoping

Thermodynamic aspects of inclusion engineering in steels

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Rare Metals 2006年第5期25卷 412-419页

作者： A.costa e silva eeIMVR-UFF Av.Trabalhadores 420Volta RedondaRJBrasil IBQN- Rio de JaneiroRJBrasil

Tailoring non-metallic inclusions in accordance to the desired effect on steel properties has gained widespread acceptance in the last decades and has become known as “inclusion engineering”. effective inclusion engineering involves three steps：（a） a good knowledge of how inclusions influence properties, （b） understanding what is the effect of each type of inclusions on these properties and thus which is the most desirable inclusion in a given product and （c） adjusting the processing parameters to obtain these inclusions. A significant portion of the process adjustment is done during steel refining, where the steel can be tailored so that the desired chemical composition of the non-metallic inclusions that will precipi- tate can be altered. Understanding the relations between steel chemistry, processing variables and inclusion chemical composition requires significant understanding of the thermodynamics of the systems involved. These complex equilibrium calculations are best done using computational thermodynamics. In this work some of the basic techniques used to control inclusion composition are reviewed and the thermodynamic information required to perform this task is presented. Several examples of the application of computational thermodynamics to inclusion engineering of different steels grades are presented and compared with experimental results, whenever possible. The potential and limitations of the method are highlighted, in special those related to thermodynamic data and databases.

关键词： computational thermodynamics steel non-metallic inclusions

Recovery of rare-earth metals from aqueous solutions by bio/adsorption using non-conventional materials:a review with recent studies and promising approaches in column applications

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Journal of Rare earths 2020年第4期38卷 339-355页

作者： Talles Barcelos da costa Meuris Gurgel Carlos da silva Melissa Gurgel Adeodato Vieira University of Campinas School of Chemical EngineeringAlbert Einstein Avenue50013083e852 CampinasBrazil

The recovery of rare-earth metals(ReMs)is of great economic and environmental interest,because of their high market prices and various industrial ***,with the increasing demand for high-purity rare-earth compounds,the separation and purification of these elements have gained considerable *** bio/adsorption process has been considered an alternative to recover these elements,by its simplicity,low cost and efficiency for recovery of ReMs at low *** review article presents the recent progress regarding ReM bio/adsorption published literature in batch system by different non-conventional bio/adsorbents,as well as a critical analysis of the technological challenges to be faced and future *** this purpose,the best application model(isotherm,kinetics),thermodynamic quantities and selection of eluents for desorption studies are also ***,in this review,the application of different bio/adsorbent materials were reviewed extensively in terms of the removal and recovery of ReMs in continuous fixed-bed adsorption and regeneration ***,future aspects in bio/adsorption research and prospects for commercial applications were discussed.

关键词： Rare-earth metals Bio/adsorbents Adsorption kinetics Isotherm Batch desorption Continuous fixed-bed adsorption

Soil texture prediction through stratification of a regional soil spectral library

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Pedosphere 2022年第2期32卷 294-306页

作者： José Janderson Ferreira costa élvio GIASSON elisangela Benedet DA silva Tales TIeCHeR Antonny Francisco Sampaio De SeNA Ryshardson Geovane Pereira de Oliveira e silva Department of Soil Science Faculty of AgronomyUniversity of Rio Grande do SulBento Gonçalves Avenue 7712Porto Alegre 91540-000Brazil Agricultural Research and Rural extension Corporation of Santa Catarina Rodovia Admar Gonzaga 1347FlorianópolisSanta Catarina 88034-901Brazil

Knowing the spatial distribution of soil texture,which is a physical property,is essential to support agricultural and environmental decision *** texture can be estimated using visible,near infrared,and shortwave infrared(Vis-NIR-SWIR)***,the performance of spectroscopic models is variable because of soil ***,few studies address the effects of soil sample variability on the performance of the models,especially for larger spectral libraries that include soils that are more ***,the objectives of this study were to:i)apply Vis-based color parameters on the stratification of a regional soil spectral library;ii)evaluate the performance of the predictive models generated from the spectral library stratification;iii)compare the performance of stratified models(SMs)and the model without stratification(WSM),and iv)explain possible changes in prediction accuracy based on the ***,a regional soil spectral library with 1535 samples from the State of Santa Catarina,Brazil was *** reflectance data were obtained by Vis-NIR-SWIR spectroscopy in the laboratory using a spectroradiometer covering the 350–2500 nm spectral ***,silt,and clay fractions were determined using the pipette ***-two components of color parameters were derived from the Vis spectrum using the colorimetric models.A cubist regression algorithm was used to assess the accuracy of the applicability of the initial models(SMs and WSM)and of the validation between the *** order derivatives(FODs)at 0.5,1.5,and 2 intervals were used to explain possible changes in the performance of the *** SMs with higher contents of clay and iron oxides obtained the highest accuracy,and the most important spectral bands were identified,mainly in the 480–550 and 850–900 nm ranges and the 1400,1900,and 2200 nm ***,stratification of soil spectral libraries is a good strategy to improve regional assessments of soil resou

关键词： color parameters cubist regression fractional order derivatives soil spectroscopy spectroscopic model stratified model Vis-NIR-SWIR

Current advances in solid free-form techniques for osteochondral tissue engineering

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Bio-Design and Manufacturing 2018年第3期1卷 171-181页

作者： Joao Bebiano costa Joana silva-Correia Rui Luis Reis Joaquim Miguel Oliveira B's Research Group I3Bs - Research Institute onBiomaterials Biodegradables and Biomimetics University ofMinho Headquarters of the European Institute of Excellenceon Tissue Engineering and Regenerative Medicine AveParkParque de Ciencia e Tecnologia Zona Industrial da Gandra4805-017 Barco Guimaraes Portugal ICVS/3B's-PT Government Associate Laboratory Braga Guimarfies Portugal The Discoveries Centre for Regenerative and PrecisionMedicine Headquarters at University of MinhoAvepark 4805-017 Barco Guimaraes Portugal

Osteochondral （OC） lesions are characterized by defects in two different zones, the cartilage region and subchondral bone region. These lesions are frequently associated with mechanical instability, as well as osteoarthritic degenerative changes in the knee. The lack of spontaneous healing and the drawbacks of the current treatments have increased the attention from the scientific community to this issue. Different tissue engineering approaches have been attempted using different polymers and different scaffolds＇ processing. However, the current conventional techniques do not allow the full control over scaffold fabrication, and in this type of approaches, the tuning ability is the key to success in tissue regeneration. In this sense, the researchers have placed their efforts in the development of solid free-form （SFF） techniques. These techniques allow tuning different properties at the micro-macro scale, creating scaffolds with appropriate features for OC tissue engineering. In this review, it is discussed the current SFF techniques used in OC tissue engineering and presented their promising results and current challenges.

关键词： Solid free-form Osteochondral Tissue engineering Scaffolds

Intranasal delivery of nanostructured lipid carriers,solid lipid nanoparticles and nanoemulsions:A current overview of in vivo studies

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Acta Pharmaceutica Sinica B 2021年第4期11卷 925-940页

作者： Cláudia Pina costa Joao Nuno Moreira JoséManuel Sousa Lobo Ana Catarina silva UCIBIO/ReQUIMTe MedtechLaboratory of Pharmaceutical TechnologyDepartment of Drug SciencesFaculty of PharmacyUniversity of PortoPorto 4050-313Portugal CNC-Center for Neuroscience and Cell Biology Center for Innovative Biomedicine and Biotechnology(CIBB)University of CoimbraFaculty of Medicine(Pólo I)Coimbra 3004-504Portugal UC-University of Coimbra CIBBFaculty of PharmacyPólo Das Ciências da SaúdeCoimbra 3000-548Portugal FP-eNAS(UFP energy Environment and Health Research Unit)CEBIMED(Biomedical Research Centre)Faculty of Health SciencesUniversity Fernando PessoaPorto 4249-004Portugal

The management of the central nervous system(CNS)disorders is challenging,due to the need of drugs to cross the blood-brain barrier(BBB)and reach the *** the various strategies that have been studied to circumvent this challenge,the use of the intranasal route to transport drugs from the nose directly to the brain has been showing promising *** addition,the encapsulation of the drugs in lipid-based nanocarriers,such as solid lipid nanoparticles(SLNs),nanostructured lipid carriers(NLCs)or nanoemulsions(Nes),can improve nose-to-brain transport by increasing the bioavailability and site-specifc *** review provides the state-of-the-art of in vivo studies with lipid-based nanocarriers(SLNs,NLCs and Nes)for nose-to-brain *** on the literature available from the past two years,we present an insight into the different mechanisms that drugs can follow to reach the brain after intranasal *** results of pharmacokinetic and pharmacodynamics studies are reported and a critical analysis of the differences between the anatomy of the nasal cavity of the different animal species used in in vivo studies is carried *** the exact mechanism of drug transport from the nose to the brain is not fully understood and its effectiveness in humans is unclear,it appears that the intranasal route together with the use of NLCs,SLNs or Nes is advantageous for targeting drugs to the *** systems have been shown to be more effective for nose-to-brain delivery than other routes or formulations with non-encapsulated drugs,so they are expected to be approved by regulatory authorities in the coming years.

关键词： Nose-to-brain delivery Intranasal administration Nanostructured lipid carriers NLC Solid lipid nanoparticles SLN Nanoemulsions In vivo studies Pharmacokinetic Pharmacodynamics

Renin-angiotensin system in the pathogenesis of liver fibrosis

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World Journal of Gastroenterology 2009年第21期15卷 2579-2586页

作者： Regina Maria Pereira Robson Augusto Souza dos Santos Filipi Leles da costa Dias Mauro Martins Teixeira Ana Cristina Simoes e silva Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais Laboratory of Hypertension Department of Physiology and BiophysicsInstitute of Biological SciencesFederal University of Minas Gerais Laboratory of Immunopharmacology Department of Biochemistry and ImmunologyInstitute of Biological SciencesFederal University of Minas Gerais

Hepatic fibrosis is considered a common response to many chronic hepatic injuries. It is a multifunctional process that involves several cell types, cytokines, chemokines and growth factors leading to a disruption of homeostatic mechanisms that maintain the liver ecosystem. In spite of many studies regarding the development of fibrosis, the understanding of the pathogenesis remains obscure. The hepatic tissue remodeling process is highly complex, resulting from the balance between collagen degradation and synthesis. Among the many mediators that take part in this process, the components of the Renin angiotensin system （RAS） have progressively assumed an important role. Angiotensin （Ang） II acts as a profibrotic mediator and Ang-（1-7）, the newly recognized RAS component, appears to exert a counter-regulatory role in liver tissue. We briefly review the liver fibrosis process and current aspects of the RAS. This review also aims to discuss some experimental evidence regarding the participation of RAS mediators in the pathogenesis of liver fibrosis, focusing on the putative role of the ACe2-Ang-（1-7）- Mas receptor axis.

关键词： Hepatic fibrosis Renin angiotensin system Angiotensin II Angiotensin-(1-7) Receptor Mas Angiotensin converting enzyme 2

Association between COVID-19 and anxiety during social isolation:A systematic review

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World Journal of Clinical Cases 2021年第25期9卷 7433-7444页

作者： erlene Roberta Ribeiro dos Santos Jose Lucas silva de Paula Felipe Maia Tardieux Vânia Nazarécosta-e-silva Amos Lal Antonio Flaudiano Bem Leite Department of Neuropsychiatry and Behavioral Science-Neurosciences Research Circle on TechnologiesStrategies and Instruments Applied to Collective HealthVitória de Santo Antão 55608680Brazil Department of Collective Health Research Circle on TechnologiesStrategies and Instruments Applied to Collective HealthVitória de Santo Antão 55608680Brazil State Audit Component of the Unified Health System State Health SecretariatRecife 50751530Brazil Department of Medicine Division of Pulmonary and Critical Care MedicineMayo ClinicRochesterMN 55905United States Department of epidemiological Surveillance Henrique de HolandaMunicipal Health SecretariatVitória de Santo Antão 55608680Brazil

BACKGROUND The uncertainties about coronavirus disease 2019(COVID-19),the change in routine,lifestyles and the reduction of physical contact can cause stress,anxiety,emotional overload,poor sleep and even physical health *** To evaluate the scientific publications available on the relationship between COVID-19 and anxiety experienced in the general population,during the period of social isolation,adopted by governmental organizations and public health policymakers as a measure to contain the spread of *** A literature search was performed systematically exploring the PubMed and Medline databases using the following terms classified as MeSH descriptors:(“anxiety”AND“pandemic”AND“COVID-19”).For the search,in the Biblioteca Virtual em Saúde–BVS,***,Web of Science and National Library plat forms, the following keywords were used: ("anxiety" AND "coronavirus" AND"social isolation"). Thirty-seven peer-reviewed articles were found. PRISMA andthe Downs & Black checklist were used for qualitative *** applying the inclusion criteria, seven (n = 7) original scientific articles wereselected. The collated evidence demonstrated increased levels of symptoms ofanxiety and depression during the period of social isolation. The populationbetween 21 to 40 years was most affected. The risk of severe depression was twiceas high at the epicenter of the pandemic. Sleep quality was significantly *** about politics, religion, and consumption of products from China werefound to generate fear and anticipate probable changes in the pattern of postpandemicconsumption. Social isolation exacerbated feelings of extreme hopelessness,sadness, loneliness and suicidal *** conclude that there is a potential relationship between social isolation duringthe COVID-19 pandemic and symptoms of anxiety. It is important to note that thedirect and indirect costs of not identifying the detrimental effects of thisphenomenon and ne

关键词： Pandemic COVID-19 Anxiety Social isolation Mental health Public health

超声波与人工智能在现场绝缘诊断中的应用(英文)

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高电压技术 2012年第8期38卷 1842-1847页

作者： Ferreira T V Germano A D silva K M costa e G Department of electrical engineering Federal University of Campina GrandeCampina Grande Institute for High Voltage Technology and Power Transmission Technische Universitt München Department of electrical engineering University of Brasília

This work studies the feasibility of implementing a system for diagnosis of electrical insulation in the field based on ultrasonic noise and artificial neural *** system,proved functional under laboratory conditions,extracts spectral information from the ultrasonic noise emitted by the corona discharges in electric equipments,and correlates it with previously defined degrees of *** achieve this classification,artificial neural networks are *** results show the viability of the method in the site;nevertheless they also show that its reliability is proportional to the size and diversity of the available database.

关键词：局部放电射频信号放电量高电压技术

effect of Cu-ZnO-Al_2O_3 supported on H-ferrierite on hydrocarbons formation from CO hydrogenation

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Chinese Journal of Catalysis 2016年第3期37卷 378-388页

作者： J.H.Flores M.e.H.Maia da costa M.I.Pais da silva 里约热内卢天主教大学生物化学系里约热内卢天主教大学物理系

Methanol synthesis catalysts based on Cu, Zn and Al were prepared by three methods and subsequently mixed with H-ferrierite zeolite in an aqueous suspension to disperse the catalysts over the support. These materials were characterized by X-ray diffraction, N2 adsorption, transmission electron microscopy, temperature programmed reduction, NH3 and H2 temperature-programmed desorption, and X-ray photoelectron spectroscopy. They were also applied to the CO hydrogenation reaction to produce dimethyl ether and hydrocarbons. The catalysts were prepared by coprecipitation under low and high supersaturation conditions and by a homogeneous precipitation method. The preparation technique was found to affect the precursor structural characteristics, such as purity and crystallinity, as well as the particle size distribution of the resulting catalyst. Low supersaturation conditions favored high dispersion of the Cu species, increasing the methanol synthesis catalyst＇s metallic surface area and resulting in a homogeneous particle size distribution. These effects in turn were found to modify the zeolite properties, promoting both a low micropore volume and blockage of the zeolite acid sites. The effect of the methanol synthesis catalyst on the reaction was verified by the correlation between the Cu surface area and the CO conversion rate.

关键词： Methanol synthesis catalyst Low supersaturation precipitation High supersaturation precipitation Syngas Hydrotalcite Hydrocarbon Dimethyl ether