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Retention of eucalyptus harvest residues reduces soil compaction caused by deep subsoiling

Journal of forestry Research 2022年第2期33卷 643-651页

作者： raphael Oliveira de Melo AymbiréAngeletti da fonseca nairam félix de Barros raphael Bragança Alves fernandes rafael da silva Teixeira Iago nery Melo Ricardo Previdente Martins soil science department Universidade Federal de ViçosaViçosaMinas GeraisBrazil BraCEll Company AlagoinhasBahiaBrazil

Eucalyptus harvesting,forwarding and soil tillage operations are among the main causes for compaction of forest soils,with potential impacts on *** concern is especially important in areas with soils that are naturally compacted(fragipans and duripans).In these soils,tillage operations include the use of subsoilers that can reach depths of more than one meter and require heavy tractors that exert high pressure on the *** of the ways to try to minimize the effect of this compaction is by retaining harvest *** objective of this study was to evaluate the impacts of eucalyptus harvesting on soil physical attributes,as well as to determine the potential of different types of residue management to reduce compaction from the soil tillage *** experiments were conducted in the same area with a Yellow *** the first experiment,compaction caused by mechanized harvesting with harvester+forwarder was *** the second experiment,different managements of harvest residues were examined as potential modifiers of soil compaction during tillage for new *** this,three managements systems were tested:(1)retention of all harvest residues and litter from the previous rotation(HR+l),(2)retention of litter from the previous rotation(l),and(3)removal of harvest residues and litter from the previous rotation(WR).Before and after harvest,sampling was carried out in the planting rows and inter-rows,and after tillage,samples were collected in the traffic line of the subsoiler-tractor *** both experiments,undisturbed soil samples were collected from the center of the 0-10,10-20,20-40,40-60,and 60-100 cm layers to determine soil density and total *** each period and site of evaluation,mechanical resistance to penetration up to the 60-cm depth was also *** harvesting operation increased soil density at 0-10 and 60-100 cm depths only in the *** of harvest residues and litter(HR+l)after harvesting avoi

关键词： soil penetration resistance Harvester+forwarder soil tillage soil density Cohesive soils

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Hot deformation and Work Hardening Behavior of an Extruded Mg–Zn–Mn–Y Alloy

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Journal of Materials science & Technology 2015年第12期31卷 1161-1170页

作者： n.Tahreen D.f.Zhang f.s.Pan X.Q.Jiang D.Y.li D.l.Chen department of Mechanical and Industrial Engineering Ryerson University College of Materials science and Engineering Chongqing University national Engineering Research Center for Magnesium Alloys Chongqing University Advanced Materials Research Center Chongqing Academy of Science and Technology faculty of Materials and Energy Southwest University department of Chemical and Materials Engineering University of Alberta

The aim of this study was to evaluate the strain hardening and hot deformation behavior of asextruded Mg-Zn-Mn （ZM31） magnesium alloy with varying Y contents （0.3, 3.2, and 6 wt%） via compression testing along the extrusion direction at room temperature, 200℃ and 300 ℃. Texture and phases were identified by X-ray diffraction. Alloy ZM31 ＋ 0.3Y consisted of a mixture of fine equiaxed grains and elon- gated grains with 1-phase （Mg3YZno）; alloy ZM31 ＋ 3.2Y contained 1-phase and W-phase （Mg3Y2Zn3）; alloy ZM31 ＋ 6Y had long-period stacking-ordered （lPsO） X-phase （Mg12YZn） and Mg24Y5 particles. With increasing Y content the basal texture became weakened significantly. While alloys ZM31 ＋ 0.3Y and ZM31 ＋ 3.2Y exhibited a skewed true stress-true stain curve with a three-stage strain hardening feature caused by the occurrence of {1072} extension twinning, the true stress-true stain curve of alloy ZM31 ＋ 6Y was normal due to the dislocation slip during compression. With increasing temperature the extent of skewness decreased. While the compressive yield stress, ultimate compressive stress, strain hardening exponent, and hardening capacity all decreased as the temperature increased, the retention of the high- temperature deformation resistance increased with increasing Y content mainly due to the presence of thermally-stable lPsO X-ohase.

关键词： Magnesium alloy Yttrium effect Temperature effect strain hardening I and W-phase lPsO X-phase

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strengthening mechanisms in magnesium alloys containing ternary Ⅰ,W and lPsO phases

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Journal of Materials science & Technology 2018年第7期34卷 1110-1118页

作者： n.Tahreen D.f. Zhang f.s. Pan X.Q. Jiang D.Y. li D.l. Chen department of Mechanical and Industrial Engineering Ryerson University Toronto Ontario MSB 2K3 Canada College of Materials science and Engineering Chongqing University Chongqing 400045 China national Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China Advanced Materials Research Center ChongqingAcademy of Science and Technology Chongqing 401123 China faculty of Materials and Energy Southwest University Chongqing 400715 China department of Chemical and Materials Engineering University of Alberta Alberta T6G 11-19 Canada

This study was aimed at identifying underlying strengthening mechanisms and predicting the yield strength of as-extruded Mg-Zn-Y alloys with varying amounts of yttrium （Y） element. The addition of Y resulted in the formation of ternary 1 （Mg3YZn6）, W （Mg3Y2Zn3） and lPsO （Mg12YZn） phases which subse- quently reinforced alloys ZM31 ＋ 0.3Y, ZM31 ＋ 3.2Y and ZM31 ＋ 6Y, where the value denoted the amount of Y element （in wt%）. Yield strength of the alloys was determined via uniaxial compression testing, and grain size and second-phase particles were characterized using OM and sEM. In-situ high-temperature XRD was performed to determine the coefficient of thermal expansion （CTE）, which was derived to be 1.38 x 10^-5 K^-1 and 2.35 x 10^-5 K^-1 for W and lPsO phases, respectively. The individual strengthening effects in each material were quantified for the first time, including grain refinement, Orowan looping, thermal mismatch, dislocation density, load-bearing, and particle shearing contributions. Grain refinement was one of the major strengthening mechanisms and it was present in all the alloys studied, irrespective of the second-phase particles. Orowan looping and crE mismatch were the predominant strengthening mechanisms in the ZM31＋0.3Y and ZM31 ＋ 3.2Y alloys containing I and W phases, respectively, while load-bearing and second-phase shearing were the salient mechanisms contributing largely to the superior yield strength of the lPsO-reinforced ZM31 ＋ 6Y alloy.2017 Published by Elsevier ltd on behalf of The editorial office of Journal of Materials science ＆ Technology.

关键词： Magnesium alloy I-phase W-phase lPsO phase strengthening mechanism

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safety of digoxin in nonagenarian patients with atrial fibrillation:lessons from the spanish Multicenter Registry

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Journal of Geriatric Cardiology 2021年第10期18卷 809-815页

作者： Pablo Domínguez-Erquicia sergio raposeiras-Roubín Emad Abu-Assi María Cespón-fernández David Alonso-Rodríguez santiago jesús Camacho-freire naiara Cubelos-fernández Álvaro lópez-Masjuán Ríos María Melendo-Viu AndrésÍñiguez-Romo department of Cardiology University HospitalÁlvaro CunqueiroVigoSpain Health Research Institute Galicia sur VigoSpain department of Cardiology University Hospital of LeónLeónSpain department of Cardiology University Hospital Juan Ramón JiménezHuelvaSpain

BACKGROUnD The association between digoxin and mortality is an unclear *** older patients with atrial fibrillation(Af),where use of digoxin is frequent,the evidence of its safety is *** aim is to assess the safety of digoxin in nonagenarian patients with *** We evaluated data from 795 nonagenarian patients with non-valvular Af from the spanish Multicenter *** analyzed the relationship between digoxin and all-cause mortality with the Cox proportional-hazards *** follow-up was 27.7±18.3 *** age was 92.5±3.8 years,and 71%of nonagenarian patients were *** was not associated with increased risk of mortality[adjusted hazard ratio(aHR)=1.16,95%CI:0.96−1.41,P=0.130].However,we found a significant increase in mortality in the subgroup with estimated glomerular filtration rate(eGfR)l/min per 1.73 m^(2)(aHR=2.01,95%CI:1.13−3.57,P=0.018),but not in the other subgroups of eGfR(30−59 ml/min per 1.73 m^(2) and≥60 ml/min per 1.73 m^(2)).When exploring the risk of mortality according to sex,male subgroup was associated with an in-crease in mortality(aHR=1.48,95%CI:1.02−2.14,P=0.041).This was not observed in females subgroup(aHR=1.03,95%CI:0.81−1.29,P=0.829).Based on the presence or absence of heart failure,we did not find significant differences(aHR=1.20,95%CI:0.87−1.65,P=0.268 ***=1.15,95%CI:0.90−1.47,P=0.273,respectively).COnClUsIOns In our large registry of nonagenarian patients with Af,we did not find an association between digoxin and mortality in the total ***,in the subgroup analyses,we found an increase in mortality with the use of digoxin in men and in patients with an eGfRl/min per 1.73 m^(2).

关键词： patients digoxin fibrillation

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Assessment of Mg(OH)_(2)/TiO_(2) coating in the Mg-Ca-Zn alloy for improved corrosion resistance and antibacterial performance

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Journal of Magnesium and Alloys 2023年第1期11卷 361-378页

作者： leonardo Hernández jes.s.ramón-sierra Montserrat soria-Castro Ángel Bacelis Geonel Rodríguez-Gattorno Elizabeth Ortiz-Vázquez Gloria Acosta Applied Physics department Center for Research and Advanced Studies of the National Polytechnic Institute(CINVESTAV-IPN)Carr.Ant.a Progreso km.6C.P.97310MeridaYucatanMexico Tecnológico nacional de México/Instituto Tecnológico de Mérida.Av.Tecnológico s/n Km.4.5 ant.Carr.Mérida-Progreso C.P.97118MéridaYucatánMéxico facultad de Química Universidad Nacional Autónoma de México(UNAM)Av.Universidad 3000C.P.04510CoyoacánCDMXMéxico

The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this *** this work,we present Mg(OH)_(2) and TiO_(2)barrier coatings to reduce the degradation of magnesium alloy(Mg-Ca-Zn)*** coatings were deposited by the anodization method and the spin-coating technique,*** anodized layer was coated with TiO_(2)generated from the hydrolysis of 3%weight of TTIP(Ti[OCH(CH_(3))_(2)]_(4),Titanium(IV)isopropoxide)in 2-Propanol deposited by the spin-coating *** the degradation in Ringer’s solution by electrochemical impedance spectroscopy and OCP revealed a 98%reduction in pittings in uncoated samples after 14 days of *** p H measurements revealed that the TiO_(2)coating reduced the alkalization of the physiological environment,keeping the pH at 6.0 *** vitro studies of two types of bacteria(*** and ***)exhibited zones of inhibition in the agar and activity bactericidal(kill time test).The mechanisms behind the improved degradation resistance and enhanced antibacterial activity are presented and discussed *** modification with Mg(OH)_(2)/TiO_(2)coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.

关键词： Magnesium alloy EIs Mg(OH)_(2) TiO_(2) Antibacterial coatings

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design of multilayer hybrid sol-gel coatings with bifunctional barrier-bioactive response on the Elektron 21 magnesium alloy for biomedical applications

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Journal of Magnesium and Alloys 2021年第6期9卷 2097-2112页

作者： K.s.Durán n.Hernández l.M.Rueda C.A.Hernández-Barrios A.E.Coy f.Viejo Grupo de Investigación en desarrollo y Tecnología de nuevos Materiales(GIMAT) Universidad Industrial de Santander9 Cra.27Colombia Grupo de Investigación de las Ciencias de las Ingenierías(GICI) Universidad de San BuenaventuraCartagenaCalle Real de TerneraDiagonal 32#30-966Colombia

The present study aims to develop multilayer barrier-bioactive hybrid sol-gel coatings from a mixture of the silane precursors tetraethylorthosilicate(TEOs)and glycidoxypropyltriethoxysilane(GPTMs)deposited on the Elektron 21 magnesium *** purpose of the inner layer(barrier coating)was to provide corrosion protection to the magnesium alloy,whereas the outer layer(bioactive coating)was doped with different Ca and Mg contents to produce a bioactive *** coatings were characterised using scanning electron microscopy(sEM)and their corrosion behaviour was evaluated by anodic polarisation and electrochemical impedance spectroscopy after immersion in simulated body fluid(sBf)at 37±0.5°*** experimental results showed that the multilayer coatings increased the corrosion resistance of the alloy up to three orders of magnitude during immersion in sBf *** the other hand,the presence of Ca and Mg in the bioactive coating promoted the growth of apatite-like ***,an increment of salt content favoured the formation of porous coatings,which allowed the access of the electrolyte to the substrate leading to their rapid *** the latter,this research endorses the premise that the TEOs-GPTMs hybrid system represents a promising alternative to produce bifunctional barrier-bioactive coatings.

关键词： Magnesium bioactivity coating sol-gel EIs corrosion

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synthesis and applications of lanthanoid complexes of pentadentate and hexadentate n_(5) and n_(6) macrocycles:A review

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Journal of rare Earths 2024年第1期42卷 1-15,I0001页

作者： Julio Corredoira-Vázquez Cristina González-Barreira Paula Oreiro-Martínez Ana M.García-deibe jesús sanmartín-Matalobos Matilde fondo departamento de Química Inorganica Facultade de QuímicaUniversidade de Santiago de CompostelaCampus Vida15782Santiago de CompostelaSpain Phantom-g CICECO-Aveiro Institute of MaterialsDepartment of PhysicsUniversity of Aveiro3810-193AveiroPortugal Institute of Materials(iMATUs) Universidade de Santiago de Compostela15782Santiago de CompostelaSpain

In this paper,the lanthanoid complexes of n_(5) and n_(6) macrocycle ligands,without pendant arms or additional heteroatoms,are *** review covers the period from 2015 to the current date,since in 2014 schiff base macrocyclic ligands incorporating the pyridine moiety,and their complexes,were revised,and in 2015 the chemistry of pentaaza macrocycle ligands with rare earth metals was also *** and phthalocyanine ligands are not included in this review,which primarily focuses on complexes with schiff bases and amines without pendant arms or any additional donor other than *** synthetic methods,structural characterization,based on single X-ray crystal data,and properties of the lanthanoid complexes,with special attention to magneto-structural correlations,are presented herein.

关键词： lanthanoid n_(5),n_(6)macrocycle Coordination chemistry Chirality Biological activity Molecule magnet

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Engineered biomimicry for harvesting solar energy:a bird’s eye view

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International Journal of smart and nano Materials 2013年第2期4卷 83-90页

作者： raúl J.Martín-Palma Akhlesh lakhtakia Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA department of Materials science and Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA department of Engineering science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA

All three methodologies of engineered biomimicry–bioinspiration,biomimetics,and bioreplication–are represented in current research on harvesting solar *** processes and porous surfaces inspired by plants and certain marine animals,respectively,are being investigated for solar *** dye-sensitized solar cells deploy artificial photosynthesis,bioinspired nanostructuring of materials in solar cells improves *** textured coatings for solar cells have been shown to reduce optical reflectance and increase optical absorptance over a broad spectral *** lenses fabricated by a bioreplication technique offer similar promise for reduced reflectance by increasing the angular field of view.

关键词： bioinspiration biomimetics bioreplication solar cell artificial photosynthesis antireflective coating engineering biomimicry

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Application of nejayote as a foliar and Edaphic fertiliser to native Blue Maize (Zea mays l.) Crops

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American Journal of Plant sciences 2016年第15期7卷 2221-2238页

作者： Victoria Téllez jesús f. lópez Agustín Aragón Teresa Zayas Posgrado en Manejo sostenible de Agroecosistemas BUAP Puebla México Centro de Agroecología BUAP Puebla México Posgrado en Ciencias Ambientales Instituto de Ciencias Benemérita Universidad Autónoma de Puebla (BUAP) Puebla México

raw and treated “nejayote” were assessed as foliar and edaphic fertilisers for native blue maize (Zea mays l.) crops in the municipality of Amozoc de Mota, Puebla, Mexico, during the 2015 agricultural cycle. Treated nejayote refers to raw nejayote subjected to a coagulation-flocculation process. Two states of nejayote were established (raw and treated nejayote) with different physicochemical properties. foliar bio-fertilisers were prepared from raw and treated nejayote and mixed with organic matter (OM) to promote a fermentation process. The foliar treatments used were: BnC5, BnC15, BnC30 (raw nejayote-based bio-fertiliser at 5%, 15%, and 30%), BnCQ5, and nCQ30 (nejayote treated by chemical coagulation at 5% and 30%), with BT as a control (traditional bio-fertiliser). The edaphic treatments used were: nC50, nC75, and nC100 (raw nejayote at 50%, 75%, 100%), with AP as a control (drinking water), thus giving rise to 10 treatments in terms of content of raw or treated nejayote. foliar and edaphic field treatments applied to native blue maize crops were statistically assessed using the following response variables: plant height, stem diameter, number of leaves, and grain yield. The experiment was laid out in a randomised complete block design (RCBD) with five replications of each treatment. The results obtained showed, that foliar or edaphic application at the different stages of development did not produce statistically significant differences, at P ≤ 0.05, in terms of response variables. The most significant effects occurred at the early stage of plant development and were mainly reflected in the stem diameter with foliar treatment nCQ30 and in the number of leaves with foliar treatment BnC5. At the final stage of crop development, the highest yield (0.639 ± 0.121 t·hasup>-1sup>) was obtained with treatment BnC5, which produced a statistically significant difference (b) in relation to the rest of the foliar and edaphic treatments (Tukey P ≤ 0.05).

关键词： Maize Crop foliar-Edaphic fertiliser raw nejayote Treated nejayote

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Processing soft ferromagnetic metallic glasses:on novel cooling strategies in gas atomization,hydrogen enhancement,and consolidation

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Journal of Materials science & Technology 2020年第24期59卷 26-36页

作者： n.Ciftci n.Yodoshi s.Armstrong l.Madler V.Uhlenwinkel leibniz Institute for Materials Engineering IWT Badgasteiner Straße 328359BremenGermany Cooperative Research and development Center for Advanced Materials Institute for Materials ResearchTohoku University2-2-1 KatahiraAoba-kuSendai980-8577Japan University of Bremen Faculty of Production EngineeringBadgasteiner Straße 128359BremenGermany

Processing soft ferromagnetic glass-forming alloys through gas atomization and consolidation is the most effective technique to produce bulk *** commercial viability of these materials depends on commercial purity ***,crystallization in commercial purity feedstock is several orders of magnitude faster than in high purity *** production of amorphous powders with commercial purity requires high cooling rates,which can only be achieved by extending the common process window in conventional gas *** development of novel cooling strategies during molten metal gas atomization on two model alloys({(fe0.6Co0.4)0.75B0.2si0.05}96nb4 and fe76B10si9P5)is *** inducement during liquid quenching significantly improved the glass-forming ability and soft magnetic properties of{(fe0.6Co0.4)0.75B0.2si0.05}96nb4 *** plasma sintering experiments verified that amorphous rings could be produced regardless of the cooling strategies *** the saturation magnetization was almost unaffected by consolidation,the coercivity increased slightly and permeability decreased *** magnetic properties of the final bulk samples were independent of feedstock *** developed cooling strategies provide a great opportunity for the commercialization of soft ferromagnetic glass-forming alloys with commercial purity.

关键词： Gas atomization Amorphous powders Metallic glass Cooling Quenching Heat transfer Hydrogen

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