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Journal of Iron and Steel Research International 2009年第4期16卷 18-21,32页

作者： Cássio Barbosa josé brant de campos Jneo Lopes do Nascimento Iêda Maria Vieira Caminha National Institute of Technology

The presence of nonmetallic inclusion particles which appear during steelmaking process is harmful to the properties of steels, which is mainly as a function of some aspects such as size, volume fraction, shape, and distribution of these particles. The automatic image analysis technique is one of the most important tools for the quantitative determination of these parameters. The classical Student approach and the Extreme Values Method （EVM） were used for the inclusion size and shape determination and the evaluation of distance between the inclusion particles. The results thus obtained indicated that there were significant differences in the characteristics of the inclusion particles in the analyzed products. Both methods achieved results with some differences, indicating that EVM could be used as a faster and more reliable statistical methodology.

关键词： image analysis steel microstructure nonmetallic inclusion

Behavior of wood basic density according to environmental variables

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Journal of Forestry Research 2022年第2期33卷 497-505页

作者： Gabriel Marcos Vieira Oliveira joséMárcio de Mello Carlos Rogério de Mello joséRoberto Soares Scolforo Eder Pereira Miguel Thiago campos Monteiro Brazil Institute of Agricultural and Forestry defense of Espírito Santo(IDAF) Av.Lourival Lugon Moulinnº300CentroJerônimo MonteiroES CEP:29.550-000Brazil department of Forestry Sciences Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Engineering department Universidade Federal de Lavras-UFLACaixa Postal 3037LavrasMG CEP:37.200-000Brazil Forestry Engineering department Faculdade de TecnologiaUniversity of Brasilia-UnBCampus Universitário Darcy RibeiroCaixa Postal 4357Asa Norte-BrasíliaDF CEP:70910-900Brazil department of Forestry Engineering and Technology Universidade Federal do Paraná-UFPRAv.Pref.Lothário Meissner632Jardim BotânicoCuritibaPR CEP:80.210-170Brazil

The relationships between climate conditions and wood density in tropical forests are still poorly *** quantify spatial dependence of wood density in the state of Minas Gerais(MG,Brazil),map spatial distribution of density,and correlate density with climate variables,we extracted data from the Forest Inventory of Minas Gerais for 1988 trees scaled throughout the territory and measured wood density of discs removed from the *** variables were extracted from the database of the Ecological-Economic Zoning of Minas *** spatial analysis,tree densities were measured at 44 georeferenced sampling *** data were subjected to exploratory analysis,variography,cross-validation,model selection,and ordinary *** relationships between wood density and environmental variables were calculated using dispersion matrices,linear correlation,and *** density proved to be highly spatially dependent,reaching a correlation of 96%,and was highly continuous over a distance of 228 *** distribution of wood density followed a continuous gradient of 514-659 kg m^(−3),enabling corre-lation with environment *** was correlated with mean annual precipitation(−0.57),temperature(0.63),and evapotranspiration(0.83).Geostatistical methods proved useful in predicting wood density in native tropical forests with different climate *** results confirmed the sensitivity of wood density to climate change,which could affect future carbon stock in forests.

关键词： Biomass Climate variables Geostatistics Hardwood Forest inventory Minas Gerais

Litter decomposition and nutrient release for two tropical N-fixing species in Rio de Janeiro,Brazil

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Journal of Forestry Research 2022年第2期33卷 487-496页

作者： David Pessanha Siqueira Giovanna campos Mamede Weiss de Carvalho joséGabriel de Souza Silva Marcos Vinicius Winckler Caldeira deborah Guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto Lamego2000Campos dos GoytacazesRio de JaneiroBrazil departamento de Ciências Florestais e da Madeira Universidade Federal do Espírito SantoAvenida Governador Lindenberg316Jerônimo MonteiroEspírito SantoBrazil department of Geosciences and Natural Resources Management University of CopenhagenRolighedsvej 23Frederisksberg CDenmark

Litter production and decomposition are critical to forest productivity,nutrient cycling,and carbon seques-tration in tropical woody ***,nutrient release and leaf litter stoichiometry in tropical legume tree plantations over the long term after outplanting are poorly understood or even *** improving our under-standing of the pattern of changes in the decomposition of N-fixing leaf litters and their possible impact on carbon stor-age,we measured litter production,mass loss and nutrient release for 240 d during litter decomposition for two tropical legume tree species(Plathymenia reticulata and Hymenaea courbaril),in Rio de Janeiro,*** production for *** was 5.689 kg ha^(−1) a^(−1) and 3.231 kg ha^(−1) a^(−1) for *** patterns of mass loss rates were similar;however,nutrient release was greater for ***,while *** showed immobilization of nutrients,especially for N,which increased by almost 20%in the early phase of decomposition followed by gradual *** from the N-fixing species did differ in nutrient chemistries over time,which was not surprising given that initial nutrient concentrations varied broadly,except for C and *** of the nutrient concentrations increased as the remaining litter mass decreased in both species,except for C and *** C:N and N:P ratios differed between the species,but N:P did not correlate to mass *** species had N-rich leaves,but *** decomposition was very likely P-limited,while *** seemed to be co-limited by N and *** results showed different patterns in nutrient release and the stoichi-ometry involved in the decomposition dynamics of the two tropical N-fixing species,even though they have similar litter decay *** species,but especially ***,may help re-establish nutrient cycling in disturbed ecosystems.

关键词： Nutrient dynamics Legume species Litter chemistry Ecological stoichiometry Tropical forest

Vegetative propagation of Apuleia leiocarpa(Vogel)***

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Journal of Forestry Research 2022年第2期33卷 455-462页

作者： joséGabriel de Souza Silva Diêgo Faustolo Alves Bispo David Pessanha Siqueira Giovanna campos Mamede Weiss de Carvalho deborah Guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto LamegoCampos dos GoytacazesRJ 2000Brazil

Apuleia leiocarpa is an environmentally and economically significant Atlantic Forest species threat-ened by ongoing *** vegetative propagation of the species could be a step forward to enable implanta-tion of clonal seed orchards and multiplication of selected trees but remains unknown to *** study assessed the mini-cutting technique for propagation of *** and determined the time required for rooting and viable mini-cutting type and *** results show that it is possible to propagate *** with mini-cuttings derived from mini-stumps produced with seeds;the mini-stumps pre-sented regrowth capacity and remained constantly produc-tive for 1 year;10-cm *** mini-cuttings should remain under misting conditions for at least 40 days,and the vegetative propagation of *** with intermediate 7-to 10-cm mini-cuttings resulted in more vigorous clonal seedlings than smaller mini-cuttings.

关键词： Mini-cutting Tropical woody species Adventitious rooting Fabaceae

Influence of physical-anatomical wood variables on charcoal physical-mechanical properties

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Journal of Forestry Research 2023年第2期34卷 531-538页

作者： Allan Motta Couto Thiago campos Monteiro Paulo Fernando Trugilho joséTarcísio Lima joséReinaldo Moreira da Silva Alfredo Napoli Diego Pierre de Almeida department of Forestry Science State University of Mato Grosso do Sul–UEMSAv.Graziela Maciel BarrosoKm 12 Zona RuralAquidauanaMS 79200000Brazil department of Forestry Engineering and Technology Federal University of Paraná–UFPRA V.Pref.Lothário Meissner 632Jardim BotânicoCuritibaPR 80210170Brazil department of Forestry Science Federal UniversityLavras–UFLALavrasMG 37200000Brazil Département de Performance des Systèmes de Production Et de Transformation Tropicaux Centre de Coopération Internationale em Recherche Agronomique pour le Développement–CIRADMontpellierFrance

This research assessed the relationship between wood physical-anatomical variables and charcoal physical-mechanical *** trees were harvested and mechanically processed into standard pieces for laboratory *** following variables were determined:wood density,fiber length and width,fiber lumen diameter and wall thickness,fiber wall fraction,and vessel *** charcoal was produced in a laboratory and gravimetric yield,relative density,and mechanical properties ***’s correlation coefficients,multivariate statistical analysis of canonical correlation,and principal component analysis were used to evaluate the relationship between wood and charcoal *** width was not significantly correlated with charcoal *** bulk density,hardness,and strength were positively correlated with wood density,fiber length,wall thickness,and wall *** properties were negatively correlated with fiber lumen diameter and vessel *** results will help identify the best wood with adequate physical-mechanical properties for industrial charcoal proces sing.

关键词： Biomass density Energy Fiber Vessel

Near-infrared leaf reflectance modeling of Annona emarginata seedlings for early detection of variations in nitrogen concentration

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Journal of Forestry Research 2023年第1期34卷 269-282页

作者： Rafaela Lancas Gomes Marília Caixeta Sousa Felipe Girotto campos Carmen Sílvia Fernandes Boaro josé Raimundo de Souza Passos Gisela Ferreira Bioestatistic Plant BiologyParasitology and Zoology DepartmentBioscience Institute(IBB)Universidade Estadual Paulista(UNESP)BotucatuSao PauloBrazil

Nitrogen(N)monitoring is essential in nurseries to ensure the production of high-quality *** spectroscopy(NIRS)is an instantaneous,nondestructive method to monitor *** data such as NIRS can also provide the basis for developing a new vegetation spectral index(VSI).Here,we evaluated whether NIRS combined with statistical modeling can accurately detect early variations in N concentration in leaves of young plants of Annona emargiaata and developed a new VSI for this *** were grown in a hydroponics system with 0,2.75,5.5or 11 mM N for 45 *** we measured gas exchange,chlorophylla fluorescence,and pigments in leaves;analyzed complete leaf nutrients,and recorded spectral data for leaves at 966 to 1685 nm using *** a statistical learning approach,the dimensionality of the spectral data was reduced,then models were generated using two classes(N deficiency,N)or four classes(0,2.75,5.5,11 mM N).The best combination of techniques for dimensionality reduction and classification,respectively,was stepwise regression(PROC STEPDISC)and linear discriminant *** was possible to detect N deficiency in seedlings leaves with 100%precision,and the four N concentrations with93.55%accuracy before photosynthetic damage to the plant ***,NIRS combined with statistical modeling of multidimensional data is effective for detecting N variations in seedlings leaves of ***.

关键词： Mineral nutrition of plants Near-infrared spectroscopy Spectral vegetation index Digital signature Statistical learning Fluorescence of chlorophylla

Endothelial progenitor cells as a therapeutic option in intracerebral hemorrhage

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Neural Regeneration Research 2017年第4期12卷 558-561页

作者： Juan Pías-Peleteiro Francisco campos josé Castillo Tomás Sobrino Clinical Neurosciences Research Laboratory Department of NeurologyStroke UnitUniversity Clinical HospitalUniversidade de Santiago de CompostelaHealth Research Institute of Santiago de Compostela (IDIS)

Intracerebral hemorrhage （ICH） is the most severe cerebrovascular disease, which represents a leading cause of death and disability in developed countries. However, therapeutic options are limited, so is mandatory to investigate repairing processes after stroke in order to develop new therapeutic strategies able to promote brain repair processes. Therapeutic angiogenesis and vasculogenesis hold promise to improve outcome of ICH patients. In this regard, circulating endothelial progenitor cells （EPCs） have recently been suggested to be a marker of vascular risk and endothelial function. Moreover, EPC levels have been associated with good neurological and functional outcome as well as reduced residual hematoma volume in ICH patients. Finally, experimental and clinical studies indicate that EPC might mediate endothelial cell regeneration and neovascularization. Therefore, EPC-based therapy could be an excellent therapeutic option in ICH. In this mini-review, we discuss the present status of knowledge about the possible therapeutic role of EPCs in ICH, molecular mechanisms, and the future perspectives and strategies for their use in clinical practice.

关键词： cellular therapy endothelial progenitor cells growth factors intracerebral hemorrhage neurorepair outcome

An innovative approach for integrated airline network and aircraft family optimization

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Chinese Journal of Aeronautics 2020年第2期33卷 634-663页

作者： joséALEXANDRE T.G.FREGNANI Bento S.de MATTOS joséA.HERNANdeS department of Aeronautical Engineering Technological Institute of Aeronautics12228-900 Sao Jose dos CamposBrazil

The determination of optimal aerial transport networks and their associated flight frequencies is crucial for the strategic planning of airlines,as well as for carrying out market research,to establish target markets,and for aircraft and crew *** addition,optimum airplane types for the selected networks are crucial to improve revenue and to provide reduced operating *** present study proposes an innovative approach to determine the optimal aerial transport network simultaneously with the determination of the optimum fleet for that network,composed of three types of airplanes(network and vehicle integrated design).The network profit is *** passenger’s demands between the airports are determined via a gravitational *** embedded linear programming solution is responsible for obtaining potential optimal network *** optimum fleet combination is determined from a database of candidate aircraft designs via genetic algorithm.A truly realistic airplane representation is made possible thanks to accurate surrogate models for engine and aerodynamics is *** accurate engine deck encompassing a compression map and an innovative engine weight calculation besides an aerodynamical artificial neural network module enable a high degree of accuracy for the mission *** proposed methodology is applied to obtain the optimum network comprised of twenty main Brazilian airports and corresponding fleet.

关键词： Air transport Aircraft design Airline economics Airline network optimization Multidisciplinary design optimization

The effect of Saccharomyces cerevisiae on digestion and mortality in the volcano rabbit(Romerolagus diazi)

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Journal of Integrative Agriculture 2015年第3期14卷 520-525页

作者： Rogelio campos-Morales Germán D Mendoza Javier Ojeda Fernando X Plata josé A Martínez Nutrition Area Surveillance General Direction of Zoos Mexico from City and Wildlife México Master Program in Animal and Agricultural Sciences Metropolitan Autonomous University (Xochimilco Unit)

An experiment was conducted to evaluate whether supplementation with a probiotic could enhance digestion and reduce mortality in the volcano rabbit in captivity. Two enclosures at Chapultepec Zoo, Mexico（114 individuals） were used in a crossover design（two periods of 60 days） with the following treatments： control group and supplementation with Saccharomyces cerevisiae（2×108 CFU/exhibit/day）. Supplementation with the probiotic negatively affected（P〈0.01） the digestibility of dry matter, organic matter, neutral detergent fiber（NDF） and energy. Mortality increased（P〈0.04） following supplementation with the probiotic（4.26% vs. 8.89%）, primarily in the juvenile rabbits. The results indicate that yeast supplementation in the volcano rabbit negatively affects digestion and mortality in captivity.

关键词： Saccharomyces cerevisiae volcano rabbit digestibility mortality

Wear protection assessment of ultralow viscosity lubricants in high-power-density engines:A novel wear prediction algorithm

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Friction 2024年第8期12卷 1785-1800页

作者： Javier BLANCO-RODRÍGUEZ Jacobo PORTEIRO joséA.LÓPEZ-campos MartíCORTADA-GARCÍA Silvia FERNÁNdeZ-CASTEJÓN CINTECX Universidade de VigoLagoas-Marcosende s/nVigo 36310Spain Repsol SA MadridSpain

Durability and reliability have been studied for decades through intensive trial-error ***,there are numerous fields of application where the costs associated with this approach are not *** lubricated machines with severe dynamic loads,such as high-power-density engines,simulation tools offer clear advantages over intensive *** and multiple scenarios can be cost-effectively simulated to assess different lubricants and engine *** work presented here details the study of wear based on a validated elastohydrodynamic(EHD)simulation model of the connecting rod journal *** model accounts for elastic deformation through a connecting rod finite element model(FEM).In addition,multiple lubricant rheological and tribological dependences,determined by specific experimental tests,are applied in the model through their interaction with the simulation ***,a novel wear algorithm is proposed to predict wear depth over time evolution along a proposed wear cycle based on the typical working ranges of high-performance engines.A final assessment is presented to compare 4 different ultralow-viscosity lubricants in their protective performance under severe *** results show the evolution of the wear load and wear depth over the wear *** evaluation is key to describing a lubricant selection procedure for high-power-density engines.

关键词： wear modelling finite element modelling mixed lubrication elastohydrodynamic(EHD) internal combustion engines bearings