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Authigenic titanite in weathered basalts: Implications for paleoatmospheric reconstructions

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Geoscience Frontiers 2020年第6期11卷 2183-2196页

作者： Alexey A.Novoselov Dailto silva Carlos Roberto de souza Filho Institute of Applied Economic Geology Universidad de ConcepcionConcepcionChile Institute of Geosciences University of CampinasCampinasSPBrazil

The stability of titanite is sensitive to temperature and partial pressure of *** finding of authigenic titanite grains in weathering regolith formed on Parana basalts,Brazil,under tropical climatic conditions,reveals the thermodynamically-driven conversion from calcite to titanite at elevated ambient *** unusual nowadays,this phase transition provides important implications for the understanding of silicate weathering in earlier geological *** types of secondary titanites were identified in the weathering profile of the study *** tiny grains of 10 μm are forming in the microscopic voids in the ***,large fractures filled with Fe-rich clay minerals contain bigger specimens of up to 170μ*** titanites of second type often coexist with chalcedony and *** carbonate minerals were found in the weathering *** sphene can be discriminated from other titanite types by its strong positive Eu anomaly,increased Al2 O3 content and low content of trace *** specific chemical composition and reactive transport modeling link this secondary mineral with dissolution of *** titanite precipitation is controlled by slow diffusion in poorly-aerated,highly-alkaline pore *** subaerial weathering of basaltic rocks provides a significant reservoir for atmospheric ***,the deposition of carbonate minerals is thermodynamically avoided at the stability field of *** demonstrate a complex feedback between CO2 and soil *** rise in pCO2 triggers the precipitation of calcite in the weathering regolith,but the greenhouse effect increasing the temperature can cease carbonate *** titanites were found in several paleosols and at least a part of them can be of weathering origin.

关键词： Titanite Sphene Calcite Paleosols Weathering Paleoclimates

Crop residues: applications of lignocellulosic biomass in the context of a biorefinery

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Frontiers in Energy 2022年第2期16卷 224-245页

作者： Maria Carolina ANDRAde Caio de Oliveira GORGULHO silva Leonora Rios de souza MOREIRA Edivaldo Ximenes FERREIRA FILHO Laboratory of Enzymology Department of Cellular BiologyUniversity of BrasiliaBrasiliaDFBrazil

Interest in lignocellulosic biomass conversion technologies has increased recently because of their potential to reduce the dependency on non-renewable feedstocks. Residues from a variety of crops are the major source of lignocellulose, which is being produced in increasingly large quantities worldwide. The commercial exploitation of crop residues as feedstocks for biorefineries which could be used to produce a variety of goods such as biofuels, biochemicals, bioplastics, and enzymes is an attractive approach not only for adding value to residues but also for providing renewable products required by the expanding bioeconomy market. Moreover, the implementation of biorefineries in different regions has the potential to add value to the specific crop residues produced in the region. In this review, several aspects of crop residue application in biorefineries are discussed, including the role of crop residues in the bioeconomy and circular economy concepts, the main technical aspects of crop residue conversion in biorefineries, the main crop residues generated in different regions of the world and their availability, the potential value-added bioproducts that can be extracted or produced from each crop residue, and the major advantages and challenges associated with crop residue utilization in biorefineries. despite their potential, most biomass refining technologies are not sufficiently advanced or financially viable. Several technical obstacles, especially with regard to crop residue collection, handling, and pre-treatment, prevent the implementation of biorefineries on a commercial scale. Further research is needed to resolve these scale-up-related challenges. Increased governmental incentives and bioeconomic strategies are expected to boost the biorefinery market and the cost competitiveness of biorefinery products.

关键词： crop residue biorefinery bioproduct biomass circular bioeconomy enzyme

Abiotic stress on seed germination and plant growth of Zeyheria tuberculosa

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林业研究:英文版 2023年第5期34卷 1511-1522页

作者： Robson Luis silva de Medeiros Rinaldo Cesar de Paula Joao Vitor Oliveira de souza Joao Pedro Peixoto Fernandes department of Agricultural Sciences School of Agricultural and Veterinarian SciencesSao Paulo State University(Unesp)14884-900JaboticabalSao PauloBrazil

Zeyheria tuberculosa(Vell.)Bureau ex *** among the Brazilian flora threatened with *** has high-quality wood and can be used to recover herbicidecontaminated ***,abiotic stresses can harm seed germination and seedling development under adverse conditions and need to be understood to improve autochthonous or indigenous biodiversity conservation and strengthen reforestation *** study evaluated the effects of temperature,water and saline stress on *** seed germination and water stress on seedling *** laboratory experiments evaluated germination under:(1)different temperatures(20,25,30,35 and 40℃);(2)different water potentials simulated with polyethylene glycol(PEG6000)at 25 and 30℃;and,(3)different osmotic potentials simulated with NaCl at 25 and 30℃.In addition,a greenhouse experiment subjected seedlings to five water regimes(20%,35%,50%,65%and 80%of maximum substrate water holding capacity).In the laboratory,seedling biometry and germination were evaluated,while physiological and morphological parameters were assessed in the *** potential of seeds increased at 25 and 30℃.Germination and vigor decreased as water and saline stresses *** tolerance thresholds for water and salt stresses were-0.6 and-0.4 MPa,*** the greenhouse,the most restrictive water regimes reduced seedling physiological and morphological *** development was compromised at moisture levels below50%field capacity.

关键词： Bignoniaceae Climate change Ipê-felpudo Ipê-preto Water stress

Effect of rare-earth oxides on properties of silicon nitride obtained by normal sintering and sinter-HIP

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Journal of Rare Earths 2012年第11期30卷 1177-1183页

作者： Cecilia C.Guedes-silva Flávio Machado de souza Carvalho José Carlos Bressiani Nuclear and Energy Research Institute-IPEN/CNEN Geoscience Institute-IGC/USP

This paper presented the microstructure, mechanical properties and oxidation behavior of silicon nitride obtained by both conventional sintering and sintering followed by hot isostatic pressing （HIP）. Silicon nitride with additives such as 5 wt.% Al2O3 and 5 wt.% Ln203 （Ln= La, La concentrate, Gd or La＋Gd） were studied. The results revealed that Gd203 additions increased the formation of elongated grains of β-Si3N4, the fracture toughness and oxidation resistance. La2O3 additions led to higher densification and hardness values, while addition of La2O3 concentrate promoted the formation of materials with intermediate properties, compared to the other studied compositions. Hot isostatic pressing increased the hardness but decreased the fracture toughness of the material, mainly because it allowed residual pores to close and also reduced the average aspect ratio of β-Si3N4 grains.

关键词： rare earths silicon nitride properties normal sintering sinter-HIP

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

Organolanthanide Compounds Containing Methanesulfonate and Pyrazinamide Ligand in Styrene Polymerization

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Journal of Rare Earths 2007年第2期25卷 135-138页

作者： Josué Garcia Quini Alessandra de souza Maia Renata Diana Miotti Tereza silva Martins Wanda de Oliveira Instituto de Qulmica Universidade de Sāo Paulo CP 26077 05513-970 Sdo Paulo-SP Brazil

The synthesis of organolanthanide compounds identified as LnCp^＊（MS）2PzA, Ln = Sm, Tb, Yb （MS = methanesulfonate, Cp^＊ = pentamethylcyclopentadienyl, and PzA = pyrazinamide）, by the reaction of coordination compounds Ln（MS）3（PzA）4 with NaCp in THF was reported. The complexes were formulated according to elemental analyses, complexometric titration with EDTA （%Ln）, and ^1H NMR. IR spectroscopy revealed that PzA coordinates with lanthanide （Ⅲ） ions and methanesulfonate coordinates via oxygen atoms in a non-equivalent manner. In preliminary catalytic studies, these compounds were active in styrene polymerization that used MAO as a cocatalyst with an activity of 12.3 kg PS molSm^-1h^-1. Differential scanning calorimetry （DSC） of polystyrene showed that the polymer was mainly atactic.

关键词： organolanthanides pentamethylcyclopentadienyl methanesulfonate pyrazinamide styrene polymerization rare earths

Influence of age in estimating maximal oxygen uptake

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Journal of Geriatric Cardiology 2016年第2期13卷 126-131页

作者： Christina G de souza silva Barry A Franklin Daniel E Forman Claudio Gil S Araujo Heart Institute Edson Saad and Medical School Federal University of Rio de Janeiro Rio de Janeiro R J Brazil Exercise Medicine Clinic CLINIMEX Rio de Janeiro R J Brazil Preventive Cardiology and Cardiac Rehabilitation William Beaumont Hospital Royal Oak MI United States Section of Geriatric Cardiology University of Pittsburgh Medical Center Geriatrics Research Education and Clinical Center System University of Pittsburgh Pittsburgh PA USA

Objective To assess the influence of age on the error of estimate （EE） of maximal oxygen uptake （VO2max） using sex and population specific-equations in cycle ergometer exercise testing, since estimated VO2 max is associated with a substantial EE, often exceeding 20%, possibly due to intrinsic variability of mechanical efficiency. Methods 1850 adults （68% men）, aged 18 to 91 years, underwent maximal cycle ergometer cardiopulmonary exercise testing. Cardiorespiratory fitness （CRF） was assessed relative to sex and age [younger （18 to 35 years）, middle-aged （36 to 60 years） and older （〉 60 years）]. VO2max [mL.（***）-1] was directly measured by assessment of gas exchange and estimated using sex and population specific-equations. Measured and estimated values of VO2max and related EE were compared among the three age- and sex-specific groups. Results Directly measured VO2max of men and women were 29.5 ± 10.5 mL.（***）-1 and 24.2 ± 9.0 mL.（kg·min） -1 （P 〈 0.01）. EE [mL·（kg·min）-1] and percent errors （%E） for men and women had similar values, 0.5 ± 3.2 and 0.4 ± 2.9 mL·（kg·min）-1, and -0.8 ± 13.1% and -1.7 ± 15.4% （P 〉 0.05）, respectively. EE and %E for each age-group were, respectively, for men： younger = 1.9 ± 4.1 mL·（kg·min）-1 and 3.8 ± 10.5%, middle-aged = 0.6 ± 3.1 mL.（kg·min）-1 and 0.4 ± 10.3%, older = -0.2 ± 2.7 mL·（kg·min） -1 and -4.2 ± 16.6% （P 〈 0.01）; and for women： younger = 1.2 ± 3.1 mL.（***）-1 and 2.7 ±10.0%, middle-aged = 0.7 ± 2.8 mL·（kg·min）-1 and 0.5 ± 11.1%, older = -0.8 ± 2.3 mL-（kg·min）-1 and -9.5 ± 22.4% （P 〈 0.01）. Conclusion VO2max were underestimated in younger age-groups and were overestimated in older age groups. Age significantly influences the magnitude of the EE of VO2max in both men and women and should be considered when CRF is estimated using population specific equations, rather than directly measured.

关键词： Aging Cardiopulmonary exercise testing Error of measurement

Fractionation of rare earth and other trace elements in crabs,Ucides cordatus,from a subtropical mangrove affected by fertilizer industry

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Journal of Environmental Sciences 2017年第4期29卷 69-76页

作者： Alice Bosco-Santos Wanilson Luiz-silva Emmanoel Vieira da silva-Filho Monique Dias Corrêa de souza Elton Luiz Dantas Margareth Sugano Navarro State University of Campinas (UNICAMP) Institute of Geosciences Department of Geology and Natural Resources Campinas Sao Paulo 13083870 Brazil . Fluminense Federal University (UFF) Institute of Chemistry Department of Geochemistry Niteroi Rio de Janeiro 24900970 Brazil University of Brasília(UnB) Institute of Geosciences Department of Geology Brasflia Distrito Federal 70910900 Brazil

Fractionation of rare earth elements（REE） and other trace metal concentrations（Th, U, Cd,Cr, Cu, Ni, Pb, and Zn） between mangrove sediments and claw muscles and shells of male crabs（Ucides cordatus） from a subtropical estuary highly impacted by fertilizer industry activities was investigated. This is the first record of REE distribution in these organisms,and the results showed higher accumulations of these metals, U and Th in shells, probably related to the replacement of Ca during molting. Contents of Cd, Cr and Ni were similar in both tissues, but Cu, Zn and Pb were mostly accumulated in the claw muscle with concentrations above those considered safe for human consumption according to the Brazilian legislation. REE fractionation was different in the analyzed tissues being softer in the shells. The results provided evidences that the water absorbed during molting controls the chemistry of REE in shells. In contrast, the chemistry of REE in the claw muscle, in which was observed preferential absorption of light REE, is controlled by diet. REE fractionation obtained for the claw muscles was closely correlated to the observed in the contaminated substrate and in materials related to the production of phosphate fertilizers（contamination source）, which supports their transference to this Ucides cordatus tissue without fractionation by the ingestion of sediments. Our results showed the potential use of crab tissues for monitoring REE and trace element sources in mangrove areas, with claw muscle exhibiting the contaminant source fingerprint.

关键词： Rare earth elements Trace metals Fertilizer contamination Crabs

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