2,613 research outputs found
Forming factors and properties of soils developed over limestone in Galicia
[Abstract] We describe the forming factors, properties, typology and distribution of soils developed over limestone in Galicia. According to the degree of development, three main tipes are distinguished. AR soils in high-erosion localities are decarbonated. AC soils formed by colluvial deposits of limestone material on, hillslopes have high carbonate levels, partly due to the greater solubility of unconsolidated material. ABR soils are found in relatively stable hillslope positions, in flat areas and cracks of rocks. Some are moderately well developed, with Bw horizons that have high carbonate content. Others are highly developed, with thick, totally decarbonated Bt horizons sometimes with low base saturation. The properties of all these soils depend on the degree of decarbonation
Caracterización de suelos con horizonte mólico formado sobre calizas en clima templado húmedo (Galicia, NW España)
[Abstract] Soils with a mollic horizon lying directly over limestone were characterized physicochemically, mineralogically and micromorphologically. The development of these soils involves dissolution of limestone and leaching of the released calcium carbonate under favourable climatic and topographic conditions, the incorporation of insoluble residues (chiefly by inheritance rather than transformation), and the action of efficient humification mechanism. They are classified as Lithic Haprendolls by Soil Taxonomy (1998) and as Rendzic Leptosols by the FAO classification (1998).
Distribution and Origin of Iron Oxides in Soils over Limestone
[Resumen] Se pretende conocer la distribuci6n y el origen de los compuestos de hierro en suelos formados sobre calizas en Galicia. Predominan las formas minerales de hierro, encontrando en la fracción arena magnetita, goethita y/o hematites y excepcionalmente ilmenita, que se consideran heredadas del material de partida. En lámina delgada se observaron goethita y hematites como granos aislados, constituyendo nódulos e integrados en fragmentos de caliza. En la arcilla, trazas de goethita están presentes en casi todos los perfiles; s610 en uno de ellos la hematites es el único 6xido de hierro. La goethita puede haberse formado tanto por neoformaci6n como por microdivisi6n a partir de las fracciones gruesas, siendo este último fen6meno el que ha originado la hematites de la fracci6n arcilla. En dos perfiles la goethita va acompañada de magnetita y se discute la posible existencía y formaci6n de maghemita.[Abstract] Iron distribution in soils formed over limestone of Galicia is studied an the origin
of the different iron forms is established. Organic iron is very scarce and mineral iron components dominate. Magnetite, goethite and / or hematite, less cornmonly ilmenite, are found in the sand fraction; they are considered as interited from the parent material. In polished sections goethite an hematite appear as single grains, nodules and il1corporated into limestone fragments. In the clay fraction, traces of goethite are present in aH except one of the profiles where only traces of hematite are indentified. Neoformation and microdivision from coarse fractions can act in the genesis of goethite; only microdivision is considered as the origin of hematite. Magnetite accompanies goethite in two profiles; the possible presence of maghemite and its origin is also discusse
PCN52 Positron Emission Tomography/Computed Tomography Imaging for Non-Small Cell Lung Cancer: A Budget Impact Analysis
Thermodynamics of the S=1 spin ladder as a composite S=2 chain model
A special class of S=1 spin ladder hamiltonians, with second- neighbor
exchange interactions and with anisotropies in the -direction, can be mapped
onto one-dimensional composite S=2 (tetrahedral S=1) models. We calculate the
high temperature expansion of the Helmoltz free energy for the latter class of
models, and show that their magnetization behaves closely to that of standard
XXZ models with a suitable effective spin , such that
, where refers to the
components of spin in the composite model. It is also shown that the specific
heat per site of the composite model, on the other hand, can be very different
from that of the effective spin model, depending on the parameters of the
hamiltonian.Comment: 17 pages, 4 figures. Submitted for publicatio
Qualidade de carcaça de novilhos terminados com dietas contendo levedura, monensina e associação de ambos aditivos
To evaluate the effects of the supplementation of feed additives on carcass quality in beef cattle, 72 Nellore steers (339.5kg, 20-month old) were feedlot finished and fed for 91 days one of the following diets: 1) control with no additives; or added of 2) live yeast culture; 3) monensin; or 4) the association of both additives. After slaughter, renal, pelvic, and inguinal fat and hot carcass weights were recorded and carcass was split into muscle, bone, and trimmable fat. Carcass Longissimus muscle area and subcutaneous fat thickness at the 12th rib were measured and steaks of Longisimus muscle were taken to determine meat color, shear force, drip, and cooking losses. Yeast increased carcass dressing percentage but there were no effects on hot carcass weight, Longissimus area, subcutaneous fat thickness, percentage and weight of retail cut yield and trimmings. Feed additives had no effect on carcass pH, meat color, fat content, shear force, and drip losses. Supplementation of yeast, monensin or the association of both additives had no important effects on carcass traits and on meat quality of feedlot finished steers.Avaliaram-se os efeitos da suplementação de aditivos alimentares sobre a qualidade de carcaça em bovinos de corte. Usaram-se 72 novilhos Nelore com média de peso de 339,5kg e 20 meses de idade, terminados em confinamento e alimentados por 91 dias com uma das quatro dietas: 1) dieta controle sem aditivos, ou com a adição de 2) leveduras vivas, 3) monensina ou 4) associação entre ambos aditivos. Após o abate, os pesos da gordura renal, pélvica e inguinal e da carcaça foram medidos e a carcaça dividida em músculos, ossos e aparas. Foram mensurados a área de olho de lombo e a espessura de gordura subcutânea sobre o músculo Longissimus na região da 12ª costela e foram obtidos bifes para a determinação da cor, força de cisalhamento e perdas por cocção e cozimento da carne. A levedura aumentou o rendimento de carcaça, mas não houve efeito dos tratamentos sobre o peso de carcaça, porção comestível e aparas. Os aditivos não influenciaram o pH da carcaça, a cor, a gordura intramuscular, a força de cisalhamento e as perdas por exsudação da carne. A suplementação, com levedura e com monensina em associação ou separadamente, não teve efeito importante sobre a qualidade da carcaça em novilhos terminados em confinamento.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP
Stability of pelargonidin 3-glucoside in model solutions in the presence and absence of flavanols
The stability of pelargonidin 3-g1ucoside (Pg3g1uc), the main anthocyanin in strawberry, has been studied in model citrate solutions (PH 3.5, 25°C) in the absence and presence flavanols (catechin and procyanidin B3) and/or oxygen. Changes in the solutions were monitorized by HPLC-DAD/MS and UV-visible spectra.Governo Português e Fundo Social Europeu através da medida n.º 5/Acção nº5.3 - PRODEP (III)(referência 5.3/N/199.006/00-Doutoramento)
Genotoxicity analysis of different magnetite-based nanoparticles applied in chemical catalysis processes
info:eu-repo/semantics/publishedVersio
Inventariação e propagação de Thymus mastichina na Beira Interior
Integrado no Programa Agro, Medida 8.1, Projecto nº 800, foram elaborados
estudos de distribuição e propagação da espécie Thymus mastichina L., existentes
espontaneamente na Beira Interior. Foram avaliadas seis zonas ecológicas distintas
denominadas Vale do Tejo, Beira Interior Sul, Cova da Beira, Beira Interior Norte,
Serra da Estrela e Serra da Gardunha.
Durante dois anos fez-se prospecção no campo em cada zona ecológica e
recolheu-se material vegetal. Realizaram-se ensaios de germinação em laboratório em
condições de temperatura alterna 10º/20ºC (dia) e temperatura constante 23ºC (dia),
com fotoperíodo de 8 e 16 horas/dia, respectivamente. Testou-se ainda a capacidade
germinativa em estufa, na Primavera e efectuaram-se ensaios de enraizamento, com
estacas terminais, em condições de Outono/Inverno e Primavera/Verão.
Na Beira Interior foram encontrados 36 locais onde se verificou a ocorrência de
Thymus mastichina. Em cada zona ecológica onde foram encontrados indivíduos da
espécie em estudo, foi seleccionado um local para recolha de 20 plantas-mãe, que foram
posteriormente instaladas no campo de caracterização/demonstração da ESACB.
Nos ensaios de germinação verificaram-se taxas entre os 80% e 94% em
laboratório e entre os 76% e 84%, em viveiro. Nos ensaios de propagação vegetativa de
estacas terminais obtiveram-se taxas de enraizamento entre os 20% e 100%
Qualidade Tecnológica E Produtividade Da Cana-de-açúcar Sob Doses De Nitrogênio Via Fertirrigação Subsuperficial Por Gotejamento
This study characterized the technological quality and yield of sugarcane cv. SP80-3280 under nitrogen doses via subsurface drip fertigation. Five treatments were established using N-fertilizer in the form of urea (0, 50, 100, 150 and 200 kg N ha-1), with four replicates, applied via subsurface drip fertigation. The technological quality (fiber% cane; Brix% juice; pol% juice, pol% cane; juice purity and total recoverable sugar -TRS), as well as yield of stalks and sugar were determined 381 days after the third harvest. The technological variables Brix%, pol% juice, purity% and TRS of sugarcane, cultivar SP80-3280, were altered by the application of nitrogen doses via subsurface drip fertigation, with significant reductions at the dose of 200 kg N ha-1. Stalk and sugar yields increased linearly with the increment in nitrogen doses applied through subsurface drip fertigation. © 2016, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.20320921
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