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Experimental Study on Split-Ring Resonators with Different Slit Widths

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Journal of Electromagnetic Analysis and Applications 2013年第9期5卷 366-370页

作者： Pedro J.Castro joaquim J.Barroso joaquim P.Leite Neto Associated Plasma Laboratory National Institute for Space Research—INPESao Jose dos CamposBrazil

Metamaterial one-dimensional periodic structures are composed of split-ring resonators, which can display electric permittivity and magnetic permeability simultaneously negative, are studied experimentally. In the present study, each resonator is made up of two concentric circular copper rings patterned on a substrate of kapton, with slits diametrically opposite each other and with the line of the splits along the longitudinal direction of the periodic array containing seven split rings evenly spaced. The experiments consist in inserting the metamaterial slab into a square waveguide of side length 6 mm, corresponding to a cutoff frequency of 25 GHz. Transmission bands due to magnetic and electrical responses are identified for slits with aperture widths of 1 mm and 2 mm, centered at 5.67 and 6.12 GHz frequencies, respectively, values well below the 25 GHz frequency cutoff, so characterizing a medium with negative permeability and permittivity.

关键词： Metamaterials Split-Ring Resonators Magnetic Response Electric Response Left-Handed Transmission Band

Strategies for Higher Education in a Global Context

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Economics World 2018年第5期6卷 370-383页

作者： Ana Bela Bravo António joaquim Serralheiro Portuguese Military Academy Lisbon Portugal Research Center of the Military Academy Lisbon Portugal Center for Spatial and Organizational Dynamics of the Algarve University Algarve Portugal Portuguese Military Academy Lisbon Portugal Research Center of the Military Academy Lisbon PortugalINESC-ID Lisbon Portugal

The growth of internationalization of higher education, both in developed and in emergent countries is a result ofglobalization. In spite of the growing literature on higher education, results from the process of internationalization,its benefits and risks, have not been widely discussed. Studies of different internationalization strategies andcomparative analysis are also scarce. This paper contributes, on the one hand, towards, a reflexion on those topicsby reviewing literature on the evolution of strategies and suggesting guidelines for a national strategy for HigherEducation （HE）; on the other hand, by analysing recent data, compares the scope of high educationinternationalization among European and other countries. There has been an evolution from mobility of studentsand staff towards transnationalization of courses and services/products from higher education institution （HEI）.Global surveys point to different approaches to internationalization and different results and perceptions. The viewthat internationalization is a condition for high performance of higher education institutions and nationalcompetitiveness does not appear to be clearly supported by evidence.

关键词： internationalization transnationalization higher education Europe Portugal strategies

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碟式离心机分离性能试验及数值模拟研究

天津大学学报（自然科学与工程技术版） 2023年第6期56卷 579-587页

作者：朱国瑞郝泽基吴将天 Pinto Lopes Maia Junior joaquim 谭蔚天津大学化工学院天津300350 天津大学浙江研究院宁波315201 浙江轻机实业有限公司杭州311401

碟式离心机作为高效分离机械广泛应用于食品、化工、制药等行业生产.为探究碟式离心机的内部流场及分离效率,进行了现场试验,并根据Σ理论建立了具有20层碟片的简化三维物理模型,利用FLUENT软件对转鼓内的流场及分离过程进行数值模拟.... 详细信息

碟式离心机作为高效分离机械广泛应用于食品、化工、制药等行业生产.为探究碟式离心机的内部流场及分离效率,进行了现场试验,并根据Σ理论建立了具有20层碟片的简化三维物理模型,利用FLUENT软件对转鼓内的流场及分离过程进行数值模拟.试验结果表明,转速和进料量对碟式离心机分离效率影响较大,提高转速、降低进料量均能提高离心机的分离效率,通过分析进出口物料的粒径发现,在试验工况下,粒径大于6μm的颗粒均能被有效分离,改变操作参数主要影响粒径为2~5μm的颗粒的分离.模拟结果表明:在碟片间隙内,物料对碟片的跟随性良好,压力与半径呈现出二次型正比关系,周向速度与半径成正比关系,在沉渣区域物料明显滞后于转鼓转动,这导致离心液压和周向速度均小于理论值,同时随着转速的提高,沉渣区域物料的滞后性更加明显;由于上升通道存在,在碟片间隙内局部位置存在明显轴向速度,从而对碟片内的流动产生干扰,导致碟片大端位置的周向速度和离心液压分布不均;在两相分离过程中,颗粒自液相中分离,沉积于上碟片的下表面,并滑落至转鼓沉渣区,固相颗粒在碟片间隙内主要堆积于定距条前侧,在相邻两个定距条之间,固相体积分数沿顺时针方向减少.研究方法与结果为碟式离心机分离性能模拟计算提供了参考,对碟式离心机的设计与结构优化提供了数据指导.

关键词：碟式离心机离心沉降数值模拟固液两相分离

Characterization of two Achromobacter xylosoxidans isolates from patients with pertussis-like symptoms

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 465-468页

作者： Fiorella Orellana-Peralta Michelle Jacinto Maria J.Pons Cláudia Gomes Carlos Bada Isabel Reyes Juana del Valle Mendoza joaquim Ruiz Facultad de Ciencias de la Salud.Universidad Peruana de Ciencias Aplicadas-LiPC LimaPeru ISGlobal Barcelona Ctr.Int.Health Res.(CRESIB)Hospital Clinic-Universitat de Barcelona Hospital de Emergencias Pediatricas.Lima Peru Instituto de Investigacion Nutrirional LimaPeru

Objective:To characterize two Achromobaeter xylosoxidans recovered from 2 patients diagnosed with pertussis during a Bordetella pertussis surveillance ***:Nasopharyngeal swabs from 2 children under 1 year of age with clinical suspicion of pertussis were analyzed by culture and ***:Two Achromobaeter xylosoxidans A8,closely related to Bordetella *** recovered from 2 patients diagnosed of pertussis,both carrying the ptxA gene and IS418 the pertussis toxin encoding ***,antibiotic susceptibility was evaluated by disk-diffusion method and by ***:Although more detailed studies are needed,the present data highlight the possibility that Achromobaeter *** related Bordetella pertussis microorganisms and not covered under the vaccine umbrella,might also result in cases of whooping *** further surveillance is necessary to determine the extension and relevance of their pathogenic role in order to discriminate their real public health implication.

关键词： Achromobacter xylosoxidans Bordetella pertussis

The Use of Data Mining Techniques in Rockburst Risk Assessment

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Engineering 2017年第4期3卷 552-558页

作者： Luis Ribeiro e Sousa Tiago Miranda Rita Leal e Sousa joaquim Tinoco State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology (Beijing) Beijing 100083 China Institute for Sustainability and Innovation in Structural Engineering Department of Civil Engineering University of Minho Campus de Azurem Guimaraes 4800-058 Portugal Masdar Institute of Science and Technology Musdar City Abu Dhabi UAE

Rockburst is an important phenomenon that has affected many deep underground mines around the world. An understanding of this phenomenon is relevant to the management of such events, which can lead to saving both costs and lives. Laboratory experiments are one way to obtain a deeper and better understanding of the mechanisms of rockburst. In a previous study by these authors, a database of rockburst laboratory tests was created; in addition, with the use of data mining （DM） techniques, models to predict rockburst maximum stress and rockburst risk indexes were developed. In this paper, we focus on the analysis of a database of in situ cases of rockburst in order to build influence diagrams, list the factors that interact in the occurrence of rockburst, and understand the relationships between these factors. The in situ rockburst database was further analyzed using different DM techniques ranging from artificial neural networks （ANNs） to naive Bayesian classifiers. The aim was to predict the type of rockburst-that is, the rockburst level-based on geologic and construction characteristics of the mine or tunnel. Conclusions are drawn at the end of the paper.

关键词： Rockburst Data mining Bayesian networks In situ database

Macauba as Promising Substrate for Crude Oil and Biodiesel Production

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Journal of Agricultural Science and Technology(B) 2012年第10期2卷 1119-1126页

作者： Roseli Aparecida Ferrari joaquim Adelino de Azevedo Filho Food Science and Quality Center Food Technology Institute ITAL Campinas S~o Paulo P.O. Box 139 CEP I3070-I 78 Brazil Department of Decentralization Development APTA Monte Alegre do Sul S6o Paulo P.O. Box O1 CEP 13910-000 Brazil

The preparation of macauba fruits （Acrocomia aculeate （Jacq.） Lodd. ex Martius） both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were characterized for their resulting oils. Experimental design was carried out to study the transesterification of each oil to obtain the concentrations of ethanol and catalyst that would provide the best biodiesel yield. A higher amount of biodiesel was produced from the best conditions to evaluate some characteristics as specified by ANP （National Agency of Petroleum, Natural Gas and Biofuels）. The results showed a variation in the fruits composition and different characteristics presented by the pulp and kernel oil. It was possible to define technological steps to obtain oil from the fruits of macauba and find the optimal conditions to biodiesel production, concentration of catalyst 4.42% and 5% and 13.3：1 and 9：1 ethanol：oil molar ratio to kernel oil and pulp oil, respectively.

关键词： Acrocomia aculeata oil extraction pulp and kernel oil.

Characteristics of Tides in the Red Sea Region, a Numerical Model Study

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Open Journal of Marine Science 2015年第2期5卷 193-209页

作者： Fawaz Madah Roberto Mayerle Gerd Bruss joaquim Bento Coastal Research Laboratory-CORELAB Research and Technology Centre West Coast (FTZ) University of Kiel Kiel Germany

In this work, a two-dimensional numerical model based on Delft3D modelling system was setup to study the tidal characteristics of the Red Sea. Besides that, analyses of available observed time series of surface elevations were carried out. Sensitivity analyses of the numerical model were carried out by testing different model parameters aiming at selecting optimal settings. The model performance was evaluated against available time series of surface elevation observations. RMS error was found to vary from 0.03 to 0.1 meter, while the ADM values range from 0.02 to 0.05 meter. On the whole, the model is able to reproduce the tidal wave in the Red Sea, reflecting a consistent level of agreement with the observations and previous works. The model results suggest that the semidiurnal tidal waves play a major role in the region except in the central part of the Red Sea where amphidromic system exists. Major semidiurnal and diurnal tidal constituents were computed to generate co-charts and form factor. The results have revealed that the distribution of the co-charts of the major semidiurnal constituents M2, N2, and S2 show the existence of anticlockwise amphidromic system in the central part of the Red Sea at about 19.5°N, north of the Strait of Bab el Mandeb at 13.5°N and in the Gulf of Suez. The chart of the diurnal tidal constituent K1 showed a single counterclockwise system in the southern part of the Red Sea centred around 15.5°N. The form factor chart shows the appearance of diurnal character in the central part of the basin and the northern end of the strait. The hydrodynamics patterns under spring and neap tidal conditions were also analysed (during flood and ebb conditions). Model results showed that currents generally are weak and strongest currents are present in the strait of Bab el Mandeb and Gulf of Suez.

关键词： Red Sea Delft3D Modelling System Amphidromic System Co-Charts

Platelet biomarkers in Alzheimer's disease

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World Journal of Psychiatry 2012年第6期2卷 95-101页

作者： Leda L Talib Helena PG joaquim Orestes V Forlenza Laboratory of Neuroscience (LIM-27) Department and Institute of PsychiatryFaculty of MedicineUniversity of S?o Paulo05403-010 S?o PauloSPBrazil

The search for diagnostic and prognostic markers in Alzheimer's disease(AD) has been an area of active research in the last decades. Biochemical markers are correlates of intracerebral changes that can be identified in biological fluids, namely: peripheral blood(total blood, red and white blood cells, platelets, plasma and serum), saliva, urine and cerebrospinal fluid. An important feature of a biomarker is that it can be measured objectively and evaluated as(1) an indicator of disease mechanisms(markers of core pathogenic processes or the expression of downstream effects of these processes), or(2) biochemical responses to pharmacological or therapeutic intervention, which can be indicative of disease modification. Platelets have been used in neuropharmacological models since the mid-fifties, as they share several homeostatic functions with neurons, such as accumulation and release of neurotransmitters, responsiveness to variations in calcium concentration, and expression of membrane-bound compounds. Recent studies have shown that platelets also express several components related to the pathogenesis of AD,in particular to the amyloid cascade and the regulation of oxidative stress: thus they can be used in the search for biomarkers of the disease process. For instance, platelets are the most important source of circulating forms of the amyloid precursor protein and other important proteins such as Tau and glycogen synthase kinase-3B. Moreover, platelets express enzymes involved in membrane homeostasis(e.g., phospholipase A2), and markers of the inflammatory process and oxidative stress. In this review we summarize the available literature and discuss evidence concerning the potential use of platelet markers in AD.

关键词： Alzheimer’s disease Biomarkers Platelets Amyloid precursor protein Glycogen synthase kinase-3B Phospholipase A2

Tilapia processing waste silage (TPWS): An alternative ingredient for Litopenaeus vannamei (Boone, 1931) diets in biofloc and clear-water systems

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Aquaculture and Fisheries 2019年第5期4卷 214-218页

作者： joaquim da Rocha Soares Neto Felipe de Azevedo Silva Ribeiro Alex Augusto Gonçalves Maurício Gustavo Coelho Emerenciano Universidade Federal Rural do Semi-Árido(UFERSA) Departamento de Ciência AnimalSetor de AquiculturaMossoró59625-900Brazil UFERSA Departamento de Ciência AnimalLaboratório de Tecnologia e Controle de Qualidade do PescadoMossoró59625-900Brazil Universidade do Estado de Santa Catarina(UDESC) Laboratório de Aquicultura(LAQ)88790-000LagunaSCBrazil and Programa de Pós-Graduação em Zootecnia(PPGZOO/UDESC)Chapecó89815-630Brazil

The aim of this study was to evaluate the growth performance of Litopenaeus vannamei juveniles reared under biofloc and clear-water conditions fed with different inclusion levels of tilapia processing waste silage(TPWS)*** experiment was performed in two individual systems:biofloc(BS)and clear-water systems(CWS).The trial used forty 40 L rectangular plastic bins(twenty per system)in a density of 63 shrimp/m^(2).The juveniles were distributed in a factorial completely randomized experimental *** treatments were based on the percentage of silage inclusion(control or 0,1.5%,3.0%,4.5%and 6.0%of inclusion)in BS or CWS,totalizing ten treatments and four *** was above 80%in all treatments and was not affected by both systems and *** final weight and SGR were statistically influenced by system(P<0.05)but not by the diet;and presented high values in *** inclusion of TPWS in *** diets did not affect shrimp *** addition,shrimp raised in BS demonstrated better growth performance as compared to CWS.

关键词： Silage Nutrition Waste BFT Pacific white shrimp