bluuebunny/crossref_metadata_2025 huggingface dataset:
Plastic Deformation and Thermal Induced Phase Transformation in 2507 Type Super Duplex Stainless Steel
Authors: Mészáros István , Bögre Bálint
Published: February 2017

The aim of this study was to investigate the effect of the previously applied cold rolling and the latter heat treatment for the eutectoidal decomposition of δ-ferrite in 2507 type superduplex stainless steel (SDSS). The samples were cold rolled at seven different deformation rates which was followed by heat treatment at were 20, 700, 750, 800 and 850 °C temperatures. The rolled and heat treated samples were investigated by hardness tester, AC magnetometer and thermoelectric power measurement. The activation energy of the decomposition was determined by the Arrhenius equation through the results of the AC magnetometer measurement.
Effect of an Ionic Liquid on the Flexural and Fracture Mechanical Properties of EP/MWCNT Nanocomposites
Authors: Szebényi Gábor , Tóth Levente Ferenc , Karger-Kocsis József
Published: February 2017

The improvement of interfacial adhesion between multiwalled carbon nanotubes (MWCNTs) and epoxy resin (EP) was investigated in nanocomposites with the addition of an ionic liquid (IL, 1-Ethyl-3-methyl imidazolium tetrafluoroborate - EMIM BF4) as interfacial adhesion promoter. MWCNT (0, 0.3 and 0.5 weight%) was dispersed in EP through diluting an MWCNT-rich masterbatch prepared in presence and absence of IL. Three point bending and compact tension (CT) fracture mechanical tests were performed on specimens with different MWCNT contents with and without IL surfactant. IL addition resulted in easier dispersion of MWCNT in the EP masterbatch. With the addition of the IL the three point bending strength, the bending modulus of elasticity and the critical force required for crack propagation have increased significantly at the optimal, 0.3 weight% MWCNT content. Scanning electron microscopic (SEM) investigation of the fracture surfaces of the CT specimens revealed that incorporation of MWCNTs and its IL-assisted dispersion produced rougher surfaces suggesting higher fracture toughness than the reference EP.
Influence of Cryogenic Attrition Ball Milling on the Particle Size of Microcrystalline Cellulose at Different Moisture Contents
Authors: Nánási Zsolt András , Hargitai Hajnalka , Mészáros László
Published: February 2017

In this study the effect of attrition ball milling on cellulose particle size distribution was studied. The effect of moisture content of cellulose and grinding time were examined and grinding was carried out at room temperature and under cryogenic conditions, as well. The grinds obtained were studied with electron microscope, and the characteristic dimensions of ground particles were determined using image processing software. Results revealed that effective size decrease of cellulose particles was achieved at low moisture content at room temperature, while under cryogenic conditions high moisture content was necessary, i.e. frozen moisture enhances grinding efficiency in the latter case.
Acoustic Barkhausen Effect Observed in Various Steels
Authors: Por Gabor , Fekete Balazs , Trampus Peter
Published: February 2017

Carrying out fatigue testing of reactor vessel material 15H2MFA acoustic emission sensors were applied to follow changes. It is shown, that observed bursts can be explained only with appearance of acoustic Barkhausen Effect (ABE). Interesting source localization is shown during heat treatment and consecutive stress test, which can be explained acoustic emission due to material transition from martenzit phase to bainite phase. Observed ABE opens the way to apply it in industry using magnetic stresses to provoke acoustic response for characterization of the state of the magnetic materials.
Position Sensitivity Study in Molecular Dynamics Simulations of Self-Organized Development of 3D Nanostructures
Authors: Fülep Dávid , Zsoldos I. , László István
Published: February 2017

The sensitivity of defect free fusion of straight carbon nanotubes from graphene nanoribbons to the position of the nanoribbon edge positions has been investigated. A basic difference between the behavior of armchair and zigzag type nanoribbons was observed. When placing armchair type graphene nanoribbons above each other identical, fitting positions are obtained automatically. Zigzag type graphene nanoribbons, however, must not be placed above each other in identical positions. From the viewpoint of defect-free fusion, according to the MD simulations symmetric on nearly symmetric positions of the ribbon edges are favorable.
Identification of Eutectic Microstructure by HPP Cellular Automata in Aluminum Alloys
Authors: Bortnyik Kornél , Barkóczy Péter
Published: February 2017

The eutectic structure of aluminum alloys has different morphology. To describe these a different image processing and analysis workflow needs to be built. To assign the different image processing steps to the different structure automatically a computational method had to be developed. In the image processing methods several cellular automata operate. For this expediently a cellular automaton was developed to classify the different eutectic structures. In materials engineering applications a HPP automata is used extensively therefore this type of automata were chosen to solve the mentioned problem. This article shows the simplicity of this method as well as the desired evaluation method.
Effect of Laser Beam Welding on the Microstructure of Duplex Stainless Steels
Authors: Fábián Enikő Réka , Dobránszky János , Csizmazia János , Ott Robert
Published: February 2017

This study addressed the evolution of microstructure across some duplex stainless steel joints welded by laser beam without and with applying additional materials. The chemical composition and the thickness of the parent material modify the welded joints profile also. Similar technological parameter results different macrostructure and ferrite content at different type of additional material. Pitting corrosion resistance were also studied.
Hot Forming of Boron Alloyed Manganese Steels
Authors: Tisza Miklós
Published: February 2017

The automotive industry always had a determining role in the whole economy. In sheet metal forming both the material and the technological developments are strongly affected by the development tendencies in car manufacturing. One of the main trends in today’s car manufacturing is to apply light weight construction principles to meet the increased customers’ demand and legal requirements. In this respect, application of high strength steels is regarded as one of the most promising possibilities. Applying high strength steels has a very positive response for many requirements: increasing strength results in the application of thinner sheets leading to significant mass reduction and simultaneously to lower consumption and less harmful emissions however it also leads to formability problems. Hot press forming is one of the most successful solutions to overcome these difficulties. In this paper, a general overview of hot press forming processes will be summarised.
Certain Weldability Problems of 6082-T6 Aluminium Alloy and the Mechanical Properties of the Welded Joints
Authors: Pósalaky Dóra , Lukács János , Török Imre
Published: February 2017

The usage of modern high strength aluminium alloys are getting more remarkable in several industry sectors mostly the fabrication of light weight structures, such as vehicles, railway transport systems, aerostructures and building constructions. The weldability problems of these alloys are more complex than the steels with similar strength. Therefore weldability problems must be analyzed very accurately, by the help of the modern physical simulation. By knowing the difficulties of the weldability of high strength aluminium alloys the proper parameters of the welding technology can be defined. This article represents the investigation of a certain weldability problem of 6082T6 aluminium alloy with the aim of physical simulation and welding experiments with gas metal arc welding and pulsed current technology.
Investigation of the Local Mechanical Properties of the SAC Solder Joint with AFM
Authors: Kámán Judit , Bonyár Attila
Published: February 2017

Considering the size of the natural appearance of the micro alloy components of a SAC solder joint, AFM was used to investigate their mechanical properties in the form of their natural appearance. Contact-mode point-spectroscopy was done to determine the elastic modulus and tapping-mode point-spectroscopy was done to investigate the tip-sample power dissipation.The measured Young’s modulus values of the Cu, IML, Ag3Sn and Sn components, were 125±9 GPa, 111±20 GPa, 67±11 GPa and 57±16 GPa, respectively. The dissipation measurements were accomplished by Si and diamond probes with different spring constants. The different characteristics of the results are discussed.
Determination of Dislocation Density in Lath Martensite by Means of Electron Backscatter Diffraction
Authors: Szabó Péter János , Csóré András
Published: February 2017

As a novel procedure for determining dislocation density, a software was improved with which data obtained by Scanning Electron Microscope (SEM) measurements can be collected and the value of superficial dislocation density can be calculated. Applying this method we investigated cold rolled lath martensitic steel samples. Besides dislocation density values, microstructure mapped by Electron Backscatter Diffraction (EBSD) will be discussed.
Residual Stress Evaluation Induced by Fatigue Crack in Shot Peened, Notched Specimens
Authors: Cseh Dávid , Mertinger Valéria , Lukács János
Published: February 2017

The advantages of applied compressive residual stress on fatigue properties of materials is a well-described topic, but the residual stress state of machine elements can change during application, therefore it is necessary to describe how these changes are related to the operational parameters. So the monitoring of residual stress relaxation gives more details to improve the lifetime. The surface residual stress state evolution of hardened (quenched and tempered), shot peened, 2 side notched quadratic fatigue specimens made of 42CrMO4 steel was investigated nondestructively by X-ray diffraction method. Residual stress state was monitored on the surface with 1 mm spatial resolution in 5 mm environment of the notch. The compressive residual stress relaxation associated the notching and the fatigue test and the reversal of sign of the residual stress (from compression to tension) associated the crack propagation were experimentally showed.
Tensile and Fracture Mechanical Properties of Styrene-Butadiene Rubbers (SBR) Filled with Industrial and Pyrolytic Carbon Blacks, and Organoclay
Authors: Berki Péter , Karger-Kocsis József
Published: February 2017

In this work we examined effects of filler combinations (industrial carbon black (CB), pelletized pyrolytic carbon black (pCBp) and organoclay (I30.P) on the tensile mechanical and fracture mechanical properties of SBR rubbers. The performance of standard N660 CB was compared with that of pCBp when used alone or in 1: 1 blend ratio at an overall filler content of 60 part per hundred part rubber (phr). The study covered also a mix composed of 20 phr pCB, 20 phr N660 and 10 phr I30.P the hardness of which was identical to those of the (p)CB filled ones. N660 yielded better tensile properties than pCBp. By contrast, the latter yielded higher tear and trouser tear strength values than CB. I30.P increased the storage modulus value (E’) in spite of the filler content of 50 phr. Presence of organoclay and pCBp also increased the critical value of the J-integral.
Poly(Lactic Acid)/Natural Rubber Blends
Authors: Hajba Sándor , Tábi Tamás
Published: February 2017

Nowadays biopolymers are in the focus of many research and Poly (lactic acid) (PLA) is the one of the candidates of this field. The rigid behavior of PLA limits its application field, thus it is mostly used for rigid packing. Our research aim is to increase PLA ductility while keeping the biodegradability as much as possible. In our study, PLA was melt mixed in an internal mixer with 5, 10, 20 and 30 wt% natural rubber. It was possible to increase the toughness to a three time higher value compared to neat PLA while the tensile and flexural properties only decreased maximum 30%.
Development of Poly(Lactic Acid) Filled with Basalt Fibres and Talc for Engineering Applications
Authors: Tábi Tamás , Zarrelli Mauro
Published: February 2017

The development of renewable resource based and inherently biodegradable polymers as well as their composites are one of the most important research fields nowadays in polymer science. Poly (Lactic Acid) (PLA), as the most promising biodegradable polymer has the potential to replace even engineering composite materials by reinforcing it with natural plant fibres or mineral fibres like basalt. However, one major drawback is its low heat deflection temperature (HDT, ~55°C) caused by its slow crystallization kinetics and thus low crystallinity of the final product. This feature also retards the usage of PLA in composite materials for elevated temperature applications. At the same time, nucleating agents like talc can be used to enhance crystallinity and thus HDT. In this paper basalt fibre reinforced and talc filled PLA composites were prepared by extrusion followed by injection moulding. The results showed that by combining the stiffness increasing effect of basalt fibres as well as the crystallinity increasing effect of talc, a composite with both high mechanical properties and high HDT could be produced.
Influence of the Phase Inversion on Mould-Shrinkage, Mechanical- and Burning Properties of Polymer Blend
Authors: Dobrovszky Károly , Ronkay Ferenc
Published: February 2017

Blending polymers is an effective method to develop novel materials, tailoring the properties of the components. However, different morphology structures can be formed during the preparation, which could result in a wide diversity of mechanical and physical properties. The properties of polymer blends are most significantly influenced by the emerging range of phase inversion, which depends on the composition ratio and the viscosity ratio. In this paper various blends were prepared, utilizing polyethylene terephthalate (PET), polystyrene (PS) and two high density polyethylenes (HDPE), which differ in flowability. After preliminary homogenization by twin screw extruder, standard injection moulded specimen were prepared in order to present the effects of phase inversion on tensile properties, shrinkage and burning characteristics in binary polymer blends.
Secrets of Abraham Ganz’s Train Wheels Enlightened by Materials Science Methods
Authors: Csanády Ágnes , Gábor János , Jenei Péter , Gubicza Jenő , Szabó Péter János , Fábián Enikő Réka , Radnóczi György , Tóth Attila Lajos , Langer Gábor , Krafcsik Olga H. , Verő Balázs
Published: February 2017

Case hardened, double-walled train wheel, produced in the foundry of Abraham Ganz in 1867 and used for long time on the railroad tracks, was studied and evaluated by modern methods of materials sciences. The investigations indicated the presence of 0.059m% antimony (Sb), distributed uniformly in the material of the wheel. This quantity is several times higher than the average Sb amounts (<0.01m%) of the other components get into the castings. Sb was detected even in the several mm thick crust; except in the outermost surface layer with < 1 µm thickness. Based on the 20th century comprehensive studies, the antimony content, detected in the wheel, was found to be ideal. In grey iron it is a powerful pearlite stabilizer which has favourable effects on its mechanical properties and serviceability.The investigation of the surface structure proved that the excellent hardness (~600 HV) at the crust surface was due to the “nano-composite” structure formed from the pearlite as a consequence of severe plastic deformation during service. This was also promoted by the high amount (4.09m%) of carbon present in the casting. The microstructure refinement during operation most probably contributes to the long service lifetime of the wheels.The secret of the Abraham Ganz’s train wheels is inherently present – besides the novel construction and production technology (case hardening) – in the above mentioned composition and the structure of the material.
Investigation of Lattice Defects in a Plastically Deformed High-Entropy Alloy
Authors: Heczel Anita , Huang Yi , Langdon Terence G. , Gubicza Jenő
Published: February 2017

The lattice defect structure developed during plastic deformation in a High-Entropy Alloy (HEA) with the composition of Ti35Zr27.5Hf27.5Nb5Ta5 was investigated. The crystallite size as well as the density and types of dislocations in a disk processed by High-Pressure Torsion (HPT) were determined by X-ray profile line analysis (XLPA). Additional transmission electron microscopy (TEM) investigations were carried out to monitor the grain size evolution during deformation. It was found that the dislocation density in the HPT-processed sample was very high compared to conventional materials. In addition, in Ti35Zr27.5Hf27.5Nb5Ta5 HEA the initial body-centered cubic structure transformed into a martensitic phase during HPT. The hardness of this HEA was investigated along the HPT-processed disk radius and correlated to the microstructure.
MIG-Welding of Dissimilar Advanced High Strength Steel Sheets
Authors: Kalácska Eszter , Májlinger Kornél , Fábián Enikő Réka , Russo Spena Pasquale
Published: February 2017

The need for steel materials with increasing strength is constantly growing. The main application of such advanced high strength steels (AHSS) is the automobile industry, therefore the welding process of different types of AHSSs in dissimilar welding joint was investigated. To simulate the mass production of thin steel sheet constructions (such as car bodies) automated metal inert gas (MIG) welding process was used to weld the TWIP (twinning induced plasticity) and TRIP (transformation induced plasticity) steel sheets together. The welding parameters were successfully optimized for butt welded joints. The joints were investigated by visual examination, tensile testing, quantitative metallography and hardness measurements. The TRIP steel side of the joints showed increased microhardness up to (450-500 HV0.1) through increased fraction of bainite and martensite. Macroscopically the tensile specimen showed ductile behaviour, they broke in the austenitic weld material.
Fatigue Curves for Aluminium Alloys and their Welded Joints Used in Automotive Industry
Authors: Lukács János , Meilinger Ákos , Pósalaky Dóra
Published: February 2017

Our research work has focused from the materials world on the aluminium alloys, from the manufacturing processes on the welding technologies, and from different loads on the cyclic loads. The article aimed (i) to demonstrate the behaviour of the friction stir welded (FSW) joints under cyclic loading conditions; (ii) to determine fatigue (limit) curves for two aluminium alloys and their welded joints. Experiments were performed on 5754-H22 and 6082-T6 aluminium alloys and their FSW joints. Both high cycle fatigue (HCF) and fatigue crack propagation (FCG) tests were executed on both base materials and their welded joints. Statistical behaviour of the base materials and welded joints was represented by the cutting of the specimens and the using of different crack paths. HCF limit curves were determined based on staircase method and FCG limit curves can be determined by own developed six step method. The investigations and their results were compared with each other and with the results can be found in the literature.
Terminology for Light and Medium Duty Trailers and Components
Authors:   Trailer Committee
Published: February 2017

This SAE standard is intended to create standard terminology related to light and medium duty trailer applications. This includes such trailer types as utility, boat, camping, travel, and special purpose trailers which are normally towed by conventional passenger cars, light-duty commercial vehicles, light trucks, and multipurpose passenger vehicles.
Impact of the 2003 ACGME Resident Duty Hour Reform on Hospital-Acquired Conditions: A National Retrospective Analysis
Authors: Wen Timothy , Attenello Frank J. , Cen Steven Y. , Khalessi Alexander A. , Kim-Tenser May , Sanossian Nerses , Giannotta Steven L. , Amar Arun P. , Mack William J.
Published: February 2017

Background

The Accreditation Council for Graduate Medical Education reforms in 2003 instituted an 80-hour weekly limit for resident physicians. Critics argue that these restrictions have increased handoffs among residents and the potential for a decline in patient safety. “Never events” hospital-acquired conditions (HACs) are a set of preventable events used as a quality metric in hospital safety analyses.

Objective

This analysis evaluated post–work hour reform effects on HAC incidence for US hospital inpatients, using the National Inpatient Sample.

Methods

Data were collected from 2000–2002 (pre-2003) and 2004–2006 (post-2003) time periods. HAC incidence in academic and non–academic centers was evaluated in multivariate analysis assessing for likelihood of HAC occurrence, prolonged length of stay (pLOS), and increased total charges.

Results

The data encompassed approximately 111 million pre-2003 and 117 million post-2003 admissions. Patients were 10% more likely to incur a HAC in the post-2003 versus pre-2003 era (odds ratio [OR] = 1.10; 95% confidence interval [CI] 1.06–1.14; P < .01). Teaching hospitals exhibited an 18% (OR = 1.18; 95% CI 1.11–1.27; P < .01) increase in HAC likelihood, with no change in nonteaching settings (OR = 1.03; 95% CI 1.00–1.06; P > .05). Patients with ≥ 1 HAC were associated with a 60% likelihood of elevated charges (OR = 1.60; 95% CI 1.50–1.72; P < .01) and 65% likelihood of pLOS (OR = 1.65; 95% CI 1.60–1.70; P < .01).

Conclusions

Post-2003 era patients were associated with 10% increased likelihood of HAC, with effects noted primarily at teaching hospitals.
Ácido indolbutírico no enraizamento de estacas de Langerstroemia indica em diferentes substratos
Authors: De Lima Daniela Macedo , Klein Anderson Wiliam , Salla Vanessa Padilha , Cardoso Moura Amanda Pacheco , Danner Moeses Andrigo
Published: February 2017

O objetivo desse trabalho foi avaliar o efeito do ácido indolbutírico (AIB) no enraizamento de estacas de resedá (Langerstroemia indica) em diferentes substratos. Estacas semi-lenhosas de 7-8 cm foram tratadas em soluções de AIB (0, 1.000, 2.000 e 3.000 mg L-1) por 10 s e estaqueadas em tubetes contendo substrato orgânico comercial ou vermiculita. Utilizou-se delineamento experimental inteiramente casualizado, em arranjo fatorial 4 x 2 (4 concentrações x 2 substratos). Aos 75 dias avaliaram-se porcentagens de estacas enraizadas, com brotações e mortas, número e comprimento de raízes e número de brotações por estaca. O AIB na concentração 1.000 mg  L-1 promoveu a melhor resposta de enraizamento (65,63%) em substrato vermiculita (73,43%).
Análise de agrupamento de espécies lenhosas da Caatinga no Estado do Pernambuco
Authors: Paes Marangon Gabriel , Felker Roselene Marostega , Zimmermann Anna Paula Lora , Ferreira Rinaldo Luíz Caraciolo , Da Silva José Antônio Aleixo
Published: February 2017

Este trabalho buscou analisar a formação de grupos ecológicos de espécies florestais lenhosas na caatinga, através da análise de agrupamento. Os dados são oriundos de duas áreas de estudo localizadas no Município de Floresta, PE, ambas com histórico de perturbação, onde os indivíduos com circunferência a 1,30 m do solo (CAP) igual ou superior a 6,0 cm foram georreferenciados, identificados, e tiveram o CAP e altura mensurados. A análise de agrupamento foi realizada através do programa Twinspan no software PC-ORD. Os resultados demonstram a formação de grupos ecológicos nas duas áreas, com a presença de espécies indicadoras.
Inclusão de resíduo da cultura de sorgo em painéis aglomerados de eucalipto
Authors: Guimarães Junior José Benedito , Xavier Michele Mantelli , Santos Thamara Silva , Protásio Thiago De Paula , Mendes Rafael Farinassi , Mendes Lourival Marin
Published: February 2017

O objetivo deste trabalho foi avaliar as qualidades físico-mecânicas de chapas aglomeradas de eucalipto produzidas com diferentes quantidades de resíduos da cultura de sorgo. Os painéis foram produzidos com 0, 15, 30 e 45% de bagaço do sorgo e 12% do adesivo uréia-formaldeído. O ciclo de prensagem utilizado foi: pressão de 4,0MPa temperatura de 180 ºC por 20 min. A qualidade das chapas foi avaliada por ensaios físico-mecânicos. Pelas avaliações físicas, todas as propriedades atenderam à norma CS 236-66, sendo que a cada 1% de sorgo acrescentado nos painéis, houve um aumento de 1,4 e 1,6% na absorção de água, a 2 e 24 h de imersão, respectivamente. Para inchamento em espessura, após 2 e 24 h de imersão, não houve efeito significativo com o aumento na porcentagem de sorgo, porém apresentaram valor médio de IE24h apenas de 1,13% acima do exigido pela norma CS 236-66, que é 30%. Em relação às propriedades mecânicas, pode-se constatar que o máximo de sorgo inserido nos painéis, para atendimento a norma CS 236-66, foi de 13%.
Qualidade de mudas de moringa sob diferentes níveis de nutrientes aplicados via fertirrigação
Authors: Pereira Kleane Targino Oliveira , Oliveira Francisco De Assis de , Cavalcante Antonio Lucieudo Gonçalves , Dantas Renata De Paiva , Oliveira Mychelle Karla Teixeira de , Costa Jessilanne Plínia Barbosa de Medeiros
Published: February 2017

O objetivo do presente trabalho foi avaliar a qualidade de mudas de moringa em função da posição das sementes no fruto e da concentração de nutrientes na solução de fertirrigação. Realizou-se um experimento seguindo o delineamento inteiramente casualizado, com os tratamentos arranjados em esquema fatorial 3 x 4, sendo três posições de sementes no fruto (basal, mediana e apical) e quatro doses de nutrientes (0, 50, 100 e 150% da dose padrão), com quatro repetições. Foram avaliados os seguintes parâmetros: altura (ALT), diâmetro do coleto (DC), número de folhas, matéria seca da parte aérea (MSPA), matéria seca do sistema radicular (MSSR) e matéria seca total, relação ALT/DC, MSPA/MSSR e índice de qualidade de Dickson. Os dados foram submetidos à análise de variância pelo teste F e as médias comparadas pelo teste de Tukey a 5% de probabilidade, para o efeito da posição da semente no fruto; e por análise de regressão, para os dados provenientes de níveis de nutrientes. A posição da semente no fruto não influenciou o vigor das mudas. Recomenda-se a solução de fertirrigação utilizando-se concentração de nutrientes variando de 80 a 100% da solução padrão adotada, para as condições deste experimento.
Dinâmica de preços e quantidades exportadas de produtos florestais brasileiros, 1995-2013
Authors: Salles Thiago Taglialegna , Isbaex Crismeire , Da Silva Márcio Lopes , Valverde Sebastião Renato , Luz Tarço Murilo Oliveira
Published: February 2017

O objetivo deste artigo foi analisar as variações no preço e na quantidade exportada de polpa de celulose, painéis de madeira, madeira serrada e papel pelo Brasil e a sua relação com a demanda e oferta, no período 1995-2013. Foram organizados graficamente dados da FAO relacionados à variação de preço e à quantidade exportada ao longo dos anos, sendo calculadas suas taxas de variação média anual através de modelos de tendência. Influenciadas pela vantagem competitiva na produção de matéria prima e por investimentos no setor, as taxas anuais de variação para exportação de polpa de celulose e de papel foram iguais a 10,13% e 2,60%, respectivamente. Relacionadas com a dinâmica da economia dos EUA, as taxas para exportações de painéis de madeira e madeira serrada foram 5,94% e -0,0087%, respectivamente. As taxas de variação dos preços foram iguais a -3,73% para polpa de celulose, -2,35% para madeira serrada, -7,35% para painéis de madeira e -5,10% para papel. As tendências de preço acompanharam a cotação do dólar. A oferta de polpa de celulose, painéis de madeira e de papel disponibilizada pelo Brasil no mercado internacional aumentou entre 1995 e 2013. No entanto, foi observada queda na demanda de madeira serrada, no período analisado.
Análise da influência do diâmetro no rendimento em madeira serrada de cambará (Qualea sp.)
Authors: Melo Rafael Rodolfo de , Rocha Matheus Justen , Rodolfo Junior Francisco , Stangerlin Diego Martins
Published: February 2017

Este trabalho teve como objetivo determinar e avaliar o rendimento da madeira serrada de Cambará (Qualea sp.) em diferentes classes de diâmetro. O estudo foi realizado em uma serraria localizada na região Norte do Estado de Mato Grosso onde foram selecionadas sessenta toras aleatoriamente e estas, agrupadas em quatro classes de quinze toras cada. As classes avaliadas apresentaram madeiras com diâmetros inferiores a 55 cm (Classe I), com diâmetros variando entre 55 e 65 cm (Classe II), entre 65 e 75 cm (Classe III) e superiores a 75 cm (Classe IV). Em média, observou-se para o cambará o rendimento médio de aproximadamente 52%. Observou-se ainda que a classe diamétrica influenciou significativamente o rendimento do cambará, sendo a Classe IV a que proporcionou à espécie o maior rendimento. Entretanto, não verificou-se tendência linear significativa para relação entre estas variáveis e sim, um comportamento parabólico, com os maiores percentuais de aproveitamento da madeira observados para a maior e menor classe avaliadas.
Predição da altura total de árvores em plantios de diferentes espécies por meio de redes neurais artificiais
Authors: Campos Bráulio Pizziolo Furtado , Silva Gilson Fernandes da , Binoti Daniel Henrique Breda , Mendonça Adriano Ribeiro de , Leite Helio Garcia
Published: February 2017

O objetivo deste trabalho foi analisar a capacidade de uma rede neural artificial (RNA) em estimar a altura total de árvores de duas espécies em diferentes condições de crescimento. Para fins de comparação, também foi ajustado o modelo hipsométrico de Campos, aplicado por estrato, conforme o gênero, espécie, rotação, espaçamento e classe de idade das árvores. A avaliação das redes neurais artificiais e do modelo de Campos foi realizada com base no coeficiente de correlação entre as alturas observadas e estimadas, a raiz quadrada do erro quadrático médio percentual e de análises gráficas. Observou-se que a altura de árvores de diferentes espécies, em distintas condições de crescimento e locais, pode ser estimada utilizando uma única rede neural, com a mesma eficiência e exatidão normalmente obtida com o emprego de equações de regressão.
Regeneração natural em Mata de Restinga em área de pecuária extensiva no Município de Pelotas, extremo Sul do Brasil
Authors: Costa Tarso Vieira da , Venzke Tiago Schuch Lemos
Published: February 2017

Foi analisada a regeneração natural em mata de restinga ocupada por pecuária extensiva no Município de Pelotas, RS. Foram delimitadas duas áreas, uma com acesso do gado ao interior da floresta e outra sem acesso (controle). Foram utilizados dois transectos com 20 parcelas sistemáticas de 2 m x 2 m distantes 5 m. Foram incluídos indivíduos arbóreo-arbustivos com no mínimo 50 cm de altura e no máximo 5 cm de DAS (diâmetro à altura do solo). Foram coletadas 27 espécies em 14 famílias. Na área controle foram encontradas 23 espécies e 316 indivíduos, enquanto na área com pecuária foram amostradas 10 espécies e 36 indivíduos. As espécies com maior densidade na área controle foram Psychotria carthagenensis Jacq. (91 ind.), Sorocea bonplandii (Baill.) W. C. Burger et al. (82), P. brachyceras Müll.Arg. (62), Trichilia elegans A.Juss. (15) e Eugenia uruguayensis Cambess. (11) e na área com pecuária foram Daphnopsis racemosa Griseb. (17 ind.), P. brachyceras (6), Solanum mauritianum Scop. (5), P. carthagenensis (2) e T. elegans (1). Os resultados mostraram diferença significativa da regeneração natural entre os dois trechos amostrados. Esses resultados corroboram com a hipótese de que a atividade pecuária influencia negativamente a riqueza e a estrutura da regeneração natural de comunidades florestais.
Influência de fertilizante de liberação controlada em mudas de Tabernaemontana catharinensis
Authors: Ferrari Mauricio , Cantarelli Edison Bisognin , Souza Velci Queiróz de , Nardino Maicon , Carvalho Ivan Ricardo , Pelegrin Alan Júnior de , Szareski Vinicius Jardel , Pelissari Guilherme
Published: February 2017

O objetivo deste trabalho foi avaliar a influência de diferentes doses de fertilizantes de liberação controlada em Tabernaemontana catharinensis. O experimento foi conduzido em Frederico Westphalen, RS, sendo testadas cinco doses e dez repetições alocadas em delineamento experimental inteiramente casualizado. As variáveis analisadas foram: incrementos de diâmetro do caule, da altura da planta e peso de matéria seca da parte área. Observou-se que o efeito das doses 3 e 6 kg m-3 comportaram-se de forma semelhante, havendo incremento no desenvolvimento de mudas de jasmim-catavento, mostrando efeitos negativos em doses mais altas.
Fertilização orgânica em sistemas silvipastoris
Authors: Matoso Stella Cristiani Gonçalves , Salman Ana Karina Dias
Published: February 2017

Diante das exigências socioambientais atuais, cresce o interesse e a necessidade por sistemas de produção agrícolas conservacionistas, como os sistemas silvipastoris. A integração de espécies arbóreas e forrageiras torna o sistema complexo, podendo ocorrer interações indesejáveis entre as espécies, como a competição por nutrientes. Para não exaurir os nutrientes do solo e obter bons rendimentos das culturas é necessário manejo adequado da adubação. Com isso, objetivou-se caracterizar o estado da arte das pesquisas sobre o efeito da adubação orgânica em sistemas silvipastoris. Foi possível constatar que o manejo da adubação orgânica é complexo, devido às características intrínsecas aos resíduos orgânicos, bem como às relações ecológicas no próprio sistema. No entanto, pode suprir e/ou diminuir a necessidade de calagem e fertilização mineral com longo efeito residual e rendimentos satisfatórios, tanto do componente arbóreo, quanto do forrageiro. Constatou-se, também, que mais pesquisas são necessárias com ênfase na variação de adubos orgânicos, técnicas de manejo, arranjos, espécies e condições edafoclimáticas.
Impact of the choice of the satellite aerosol optical depth product in
a sub-regional dust emission inversion
Authors: Escribano Jerónimo , Boucher Olivier , Chevallier Frédéric , Huneeus Nicolás
Published: February 2017

Abstract. Mineral dust is the major continental contributor to the global atmospheric aerosol burden with important effects on the climate system. Regionally, a large fraction of the emitted dust is produced in North Africa, however the total emission flux from this region is still highly uncertain. In order to reduce these uncertainties, emission estimates through top-down approaches (i.e., usually models constrained by observations) had been successfully developed and implemented. Such studies usually rely on a single observational dataset and propagate the possible observational errors of this dataset onto the emission estimates. In this study, aerosol optical depth (AOD) products from five different satellites are assimilated one by one in a source inversion system to estimate dust emission fluxes over northern Africa and the Arabian Peninsula. We estimate mineral dust emissions for the year 2006 and discuss the impact of the assimilated dataset on the analysis. We find a relatively large dispersion in flux estimates among the five experiments, which can likely be attributed to differences in the assimilated observation datasets and their associated error statistics. We also show how the assimilation of a variety of AOD products can help to identify systematic errors in models.
Response of Trace Gases to the Disrupted
2015–2016 Quasi-Biennial Oscillation
Authors: Tweedy Olga V. , Kramarova Natalya A. , Strahan Susan E. , Newman Paul A. , Coy Lawrence , Randel William J. , Park Mijeong , Waugh Darryn W. , Frith Stacey M.
Published: February 2017

Abstract. The quasi-biennial oscillation (QBO) is a quasi-periodic alternation between easterly and westerly zonal winds in the tropical stratosphere, propagating downward from the middle stratosphere to the tropopause with a period that varies from 24 to 32 months (∼28 months on average). The QBO wind oscillations affect the distribution of chemical constituents, such as ozone (O3), water vapor (H2O), nitrous oxide (N2O) and hydrochloric acid (HCl), through the QBO induced meridional circulation. In the 2015–2016 winter, radiosonde observations revealed an anomaly in the downward propagation of the westerly phase, which was disrupted by the upward displacement of the westerly phase from ∼30 hPa up to 15 hPa, and the sudden appearance of easterlies at 40 hPa. Such a disruption is unprecedented in the observational record from 1953–present. In this study we show the response of trace gases to this QBO disruption using O3, HCl, H2O and temperature from the Aura Microwave Limb Sounder (MLS) and total ozone measurements from the Solar Backscatter Ultraviolet (SBUV) Merged Ozone Data Set (MOD). Results reveal development of positive anomalies in stratospheric equatorial O3 and HCl over ∼50–30 hPa in May–September of 2016 and a substantial decrease in O3 in the subtropics of both hemispheres. The SBUV observations show near record low levels of column ozone in the subtropics in 2016, resulting in an increase of surface UV index during northern summer. Furthermore, cold temperature anomalies near the tropical tropopause result in a global decrease in stratospheric water vapor.
Interactions among temperature, moisture, and oxygen concentrations in controlling decomposition rates in a boreal forest soil
Authors: Sierra Carlos A. , Malghani Saadatullah , Loescher Henry W.
Published: February 2017

Abstract. Determining environmental controls on soil organic matter decomposition is of importance for developing models that predict the effects of environmental change on global soil carbon stocks. There is uncertainty about the environmental controls on decomposition rates at temperature and moisture extremes, particularly at high water content levels and high temperatures. It is uncertain whether observed declines in decomposition rates at high temperatures are due to declines in the heat capacity of extracellular enzymes as predicted by thermodynamic theory, or due to simultaneous declines in soil moisture. It is also uncertain whether oxygen limits decomposition rates at high water contents. Here we present the results of a full factorial experiment using organic soils from a boreal forest incubated at high temperatures (25 and 35 °C), a wide range of water-filled pore space (WFPS; 15, 30, 60, 90 %), and contrasting oxygen concentrations (1 and 20 %). We found support for the hypothesis that decomposition rates are high at high temperatures, provided that enough moisture and oxygen are available for decomposition. Furthermore, we found that decomposition rates are mostly limited by oxygen concentrations at high moisture levels; even at 90 % WFPS, decomposition proceeded at high rates in the presence of oxygen. Our results suggest an important degree of interaction among temperature, moisture, and oxygen in determining decomposition rates at the soil core scale.
Should seasonal rainfall forecasts be used for flood preparedness?
Authors: Coughlan de Perez Erin , Stephens Elisabeth , Bischiniotis Konstantinos , van Aalst Maarten , van den Hurk Bart , Mason Simon , Nissan Hannah , Pappenberger Florian
Published: February 2017

Abstract. In light of strong encouragement for disaster managers to use climate services for flood preparation, we question whether seasonal rainfall forecasts should indeed be used as indicators of the likelihood of flooding. Here, we investigate the primary drivers of flooding at the seasonal timescale across sub-Saharan Africa. Given the sparsity of hydrological observations, we input bias-corrected reanalysis rainfall into the Global Flood Awareness System to identify seasonal indicators of floodiness. Results demonstrate that in wet climates, even a perfect tercile forecast of seasonal total rainfall would provide little to no indication of the seasonal likelihood of flooding. The number of extreme events within a season shows the highest correlations with floodiness consistently across regions. Otherwise, results vary across climate regimes: floodiness in arid regions in Southern and Eastern Africa shows the strongest correlations with seasonal average soil moisture and seasonal total rainfall. Floodiness in wetter climates of West and Central Africa and Madagascar shows the strongest relationship with measures of the intensity of seasonal rainfall. Measures of rainfall patterns, such as the length of dry spells, are least related to seasonal floodiness across the continent. Ultimately, identifying the drivers of seasonal flooding can be used to improve forecast information for flood preparedness, and avoid misleading decision-makers.
Validation of terrestrial water storage variations as simulated by different global numerical models with GRACE satellite observations
Authors: Zhang Liangjing , Dobslaw Henryk , Stacke Tobias , Güntner Andreas , Dill Robert , Thomas Maik
Published: February 2017

Abstract. Estimates of terrestrial water storage (TWS) variations from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are used to assess the accuracy of four global numerical model realizations that simulate the continental branch of the global water cycle. Based on four different validation metrics, we demonstrate that for the 31 largest discharge basins worldwide all model runs agree with the observations to a very limited degree only, together with large spreads among the models themselves. Since we apply a common atmospheric forcing data set to all hydrological models considered, we conclude that those discrepancies are not entirely related to uncertainties in meteorologic input, but instead to the model structure and parametrization, and in particular to the representation of individual storage components with different spatial characteristics in each of the models. TWS as monitored by the GRACE mission is therefore a valuable validation data set for global numerical simulations of the terrestrial water storage since it is sensitive to very different model physics in individual basins, which offers helpful insight to modellers for the future improvement of large-scale numerical models of the global terrestrial water cycle.
Synoptic fluctuation of the Taiwan Warm Current in winter on the East China Sea shelf
Authors: Xuan Jiliang , Huang Daji , Pohlmann Thomas , Su Jian , Mayer Bernhard , Ding Ruibin , Zhou Feng
Published: February 2017

Abstract. The seasonal mean and synoptic fluctuation of the wintertime Taiwan Warm Current (TWC) were investigated using a well-validated finite volume community ocean model. The spatial distribution and dynamics of the synoptic fluctuation were highlighted. The seasonal mean of the wintertime TWC has two branches: an inshore branch between the 30 and 100 m isobaths and an offshore branch between the 100 and 200 m isobaths. The Coriolis term is much larger than the inertia term and is almost balanced by the pressure gradient term in both branches, indicating geostrophic balance of the mean current. Two areas with significant fluctuations of the TWC were identified during wintertime. One of the areas is located to the north of Taiwan with velocities varying in the cross-shore direction. These significant cross-shore fluctuations are driven by barotropic pressure gradients associated with the intrusion of the Taiwan Strait Current (TSC). When a strong TSC intrudes to the north of Taiwan, the isobaric slope tilts downward from south to north, leading to a cross-shore current from the coastal area to the offshore area. When the TSC intrusion is weak, the cross-shore current to the north of Taiwan is directed from offshore to inshore. The other area of significant fluctuation is located in the inshore area between the 30 and 100 m isobaths. The fluctuations are generally strong both in the alongshore and cross-shore directions, in particular at the latitudes 26.5 and 28° N. Wind affects the synoptic fluctuation through episodic events. When the northeasterly monsoon prevails, the southwestward Zhe-Min coastal current dominates the inshore area associated with a deepening of the mixed layer. When the winter monsoon is weakened or the southwesterly wind prevails, the northeastward TWC dominates in the inshore area.
Exchange Rate Variations and Agricultural Exports in Vietnam
Authors: Dinh Cuong Xuan , Nguyen Toan
Published: February 2017

This article studies the situation of exchange rate since the end of 2014 until now and gives analysis about the effects of exchange rate viariations on agricultural export market of Vietnam in this period. Specifically, we focuse on the adjustments of the State Bank of Vietnam as the US dollar’s price fluctuates and yuan is devalued. Besides, we also analyse the consequences that agriculture is affected by unfavorable changes of the market.
Quantitative Structure–activity Relationship Studies of Flavonoids Substituted as Anticancer Agents Activity against the Growth of the Hepatic Cancer Cell lines HepG2
Authors: Radhi Wisam A. , Ismael Sadiq M. H. , Al-Shawi Jasim M. , Hussein Kawkab A.
Published: February 2017

Quantitative Structure–Activity Relationship (QSAR) models, based on molecular descriptors, derived from molecular structures, have been used for the prediction for computed the Hepatic Cancer Cell lines HepG2 of flavonoids substituted. QSAR model including some molecular descriptors, regression quality indicates that these descriptors provide valuable information and have significant role in the assessment of the cytotoxicity of compounds under study. Four QSAR equations, for the prediction of cytotoxicity, have been drawn up by using the multiple regression technique, (Eqs 1-4) with the values of R2 ranged from 0.767-0.797, Q2 ranged from 0.765-0.796 and the values of S ranged from 7.051-7.391, while the values of F ranged from 9.328-10.354. The results have shown excellent model by Eq 4. with high R2,F and minimum S by using eight  parameters [Gm, nO, nH, nCIC, nBM, nAB, D.M and Ku], and have found and indicated that these parameters have significant role in determining the properties of cytotoxicity. This result encourages the application of QSAR to a wider selection of compounds properties.
Het legaat aan een erfgenaam: een gewoon legaat?
Authors: Boelens G.G.B.
Published: February 2017

Het legaat aan een erfgenaam: een gewoon legaat?

In deze bijdrage wordt stilgestaan bij het legaat aan een erfgenaam en de vraag of, en zo ja, in hoeverre, een dergelijk legaat verschilt van een legaat aan een derde (niet-erfgenaam). Mijn conclusie luidt dat een legaat aan een erfgenaam altijd voor het geheel onder bijzondere titel wordt verkregen (behoudens de toepassing van art. 4:228 lid 2 BW), net als elk ander legaat aan een derde. Het aan een erfgenaam gelegateerde goed moet op dezelfde wijze ‘voor’ de verdeling aan de legataris-erfgenaam worden geleverd als dat het gelegateerde goed aan de legataris-niet-erfgenaam ‘voor’ de verdeling moet worden geleverd. Het onderscheid tussen een legaat, een prelegaat en de bijzondere variant daarvan, zijnde het voorafnemingslegaat, acht ik dan ook verwarrend en niet noodzakelijk.
Het willekeurige karakter van de verboden beschikkingen
Authors: de Jonge H.J.
Published: February 2017

Het willekeurige karakter van de verboden beschikkingen

In deze bijdrage gaat de auteur in op het willekeurige karakter van de verboden beschikkingen in het erfrecht. Men kan zich afvragen waarom een curator niet uitgesloten is van het genieten van voordeel uit een uiterste wilsbeschikking van zijn curandus. Men zou zich op het standpunt kunnen stellen dat artikel 4:57 lid 1 BW van overeenkomstige toepassing is op testamentaire bevoordelingen van een onder curatele gestelde ten behoeve van zijn curator. De heersende opvatting in de literatuur is echter dat er geen sprake is van een overeenkomstige onbevoegdheid. De auteur meent dat er voldoende argumenten zijn om de vraag naar een wettelijke regeling (opnieuw) aan de orde te stellen.