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1.
Colloq. agrar. ; 17(6): 22-37, nov.-dez. 2021. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: vti-33026

RESUMO

This study aimed to evaluate the effect of organic and inorganic fertilizers on the pitayas Hylocereus undatusperformance under field conditions. The experimental design used was Completely Randomized Block Design (CRBD). Five treatments consisting of the four different fertilizer dosages were included in this study, namely T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) and T5 (Control: 00-000-000-000) of bovine manure (kg pit-1), urea (g pit-1), super simple (g pit-1) and potassium chloride (g pit-1), respectively. Parameters such as height, number, length, width, area, and volume of the cladodes were assessed at 20 and 320 days after planting. The number of fruits produced and mineral composition (N, K, Ca, Mg, P, and S) of H. undatusplants were also assessed. The results on morphometric characteristics of the cladodes, macronutrient composition and fruit yield have been recorded with higher values in treatments 3 and 4. However, according to the principal component analysis performed, treatment 3 was the one that correlated with the evaluated characteristics. The results have clearly indicatedthe importance of combination of adequate dose of mineral and organic fertilizer for better vegetative performance and yield of pitaya crop.(AU)


Este estudo tevepor objetivoavaliar o efeito defertilizantes orgânicos e inorgânicos sobre o desempenho da pitayaHylocereus undatusem condições de campo.O delineamento experimental utilizado foi Delineamento emBlocos Completamente Casualizados (DBC).Foram incluídos neste estudo cinco tratamentos constituídos por quatro diferentes dosagens de fertilizantes, nomeadamente T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) e T5 (Controle: 00-000-000-000) de estercobovino (kg cova-1), ureia (g cova-1), super simples (g cova-1) e cloreto de potássio (g cova-1), respectivamente. Parâmetros como altura, número, comprimento, largura, área e volume dos cladódios foram avaliados aos 20 e 320 dias após oplantio.O número de frutos produzidos e a composição mineral (N, K, Ca, Mg, P, e S) das plantas H. undatusforam também avaliados. Os resultados sobre as características morfométricas dos cladódios, composição de macronutrientes e rendimento de frutos foram registados com valores mais elevados nos tratamentos 3 e 4. No entanto, de acordo com a análise dos componentes principais (PCA) realizada, o tratamento 3 foi o que mais se correlacionou com as características avaliadas. Os resultados indicaram claramente a importância da combinação de doses adequadas de fertilizante mineral e orgânico para um melhor desempenho vegetativo e rendimento da cultura da pitaya.(AU)


Assuntos
Compostos Orgânicos/análise , Compostos Orgânicos/química , Compostos Inorgânicos/análise , Compostos Inorgânicos/química , Caryophyllales/crescimento & desenvolvimento
2.
Colloq. Agrar ; 17(6): 22-37, nov.-dez. 2021. tab, graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1481671

RESUMO

This study aimed to evaluate the effect of organic and inorganic fertilizers on the pitaya’s Hylocereus undatusperformance under field conditions. The experimental design used was Completely Randomized Block Design (CRBD). Five treatments consisting of the four different fertilizer dosages were included in this study, namely T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) and T5 (Control: 00-000-000-000) of bovine manure (kg pit-1), urea (g pit-1), super simple (g pit-1) and potassium chloride (g pit-1), respectively. Parameters such as height, number, length, width, area, and volume of the cladodes were assessed at 20 and 320 days after planting. The number of fruits produced and mineral composition (N, K, Ca, Mg, P, and S) of H. undatusplants were also assessed. The results on morphometric characteristics of the cladodes, macronutrient composition and fruit yield have been recorded with higher values in treatments 3 and 4. However, according to the principal component analysis performed, treatment 3 was the one that correlated with the evaluated characteristics. The results have clearly indicatedthe importance of combination of adequate dose of mineral and organic fertilizer for better vegetative performance and yield of pitaya crop.


Este estudo tevepor objetivoavaliar o efeito defertilizantes orgânicos e inorgânicos sobre o desempenho da pitayaHylocereus undatusem condições de campo.O delineamento experimental utilizado foi Delineamento emBlocos Completamente Casualizados (DBC).Foram incluídos neste estudo cinco tratamentos constituídos por quatro diferentes dosagens de fertilizantes, nomeadamente T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) e T5 (Controle: 00-000-000-000) de estercobovino (kg cova-1), ureia (g cova-1), super simples (g cova-1) e cloreto de potássio (g cova-1), respectivamente. Parâmetros como altura, número, comprimento, largura, área e volume dos cladódios foram avaliados aos 20 e 320 dias após oplantio.O número de frutos produzidos e a composição mineral (N, K, Ca, Mg, P, e S) das plantas H. undatusforam também avaliados. Os resultados sobre as características morfométricas dos cladódios, composição de macronutrientes e rendimento de frutos foram registados com valores mais elevados nos tratamentos 3 e 4. No entanto, de acordo com a análise dos componentes principais (PCA) realizada, o tratamento 3 foi o que mais se correlacionou com as características avaliadas. Os resultados indicaram claramente a importância da combinação de doses adequadas de fertilizante mineral e orgânico para um melhor desempenho vegetativo e rendimento da cultura da pitaya.


Assuntos
Caryophyllales/crescimento & desenvolvimento , Compostos Inorgânicos/análise , Compostos Inorgânicos/química , Compostos Orgânicos/análise , Compostos Orgânicos/química
3.
Acta Vet. Brasilica ; 16(3): 251-261, ago. 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1392726

RESUMO

This study aimed to determine the mineral composition, fatty acid profile, omegas and lipid quality indexes in the visceral fat residues of tambaqui (C. macropomum). Three pieces of visceral fat were collected from 20 fish weighing 1.10 ± 0.10 kg, which were homogenized and sent for compositional analysis. Minerals were determined by AOAC Official method 969.23 and 968.08. The fatty acids were grouped to calculate the ∑PUFAs/∑SFAs fatty acids ratio and the proportion of polyunsaturated fatty acids ∑PUFAs (n-6/n-3), atherogenicity indixes (AI) were calculated, thrombogenicity (TI), and ratio between hypocholesterolemic and hypercholesterolemic fatty acids (HH). Mineral elements were found, 0.68 ± 0.015 mg/100g of total iron, 159.16 ± 14.32 mg/100g of Na+, 63.90 ± 5.11 mg/100g of K+, 10.28 ± 0. 62 mg/100g of Ca2+and 7.31 ± 0.58 mg/100g of Mg2+. As for fatty acids, 40.10% of SFAs, 38.10% of MUFAs and 21.80% of PUFAs. The calculations indicated significant values of omegas, 3, 6, 7 and n-7. There were ∑PUFAs/∑SFAs ratios of 1.84 and ∑PUFAs(n-6/n-3) of 6.22, with an AI of 0.50 and a TI of 0.93 and HH of 2.16. The 1.0 ± 0.10 kg tambaqui visceral fat residues can be evaluated as having high nutritional value, in addition to being a viable option for oil extraction and inclusion in animal feed.(AU)


O objetivo do estudo foi determinar a composição mineral, perfil de ácidos graxos, omegas e índices de qualidade lipíca de resíduos de gordura visceral de tambaqui (C. macropomum). Foram três amostras de gordura visceral coletadas de 20 peixes de 1,10 ± 0,10 kg, os quais foram homogeneizados e enviados para análise composicional. Os minerais foram deter-minados pelo método oficial AOAC 969,23 e 968,08. Os ácidos graxos foram agrupados para calcular a proporção de ácidos graxos ∑PUFAs/∑SFAs e a proporção de ácidos graxos poli-insaturados ∑PUFAs (n-6/n-3), índices de aterogenicidade (IA) foram calculados, trombogenicidade (IT) e proporção entre ácidos graxos hipocolesterolêmicos e hipercolesterolêmicos (HH). Foram encontrados os elementos minerais, 0,68 ± 0,015 mg/100g de ferro total, 159,16 ± 14,32 mg/100g de Na+, 63,90 ±5,11 mg/100g de K+, 10,28 ± 0,22 mg/100g de Ca2+ e 7,31 ± 0,58 mg/100g de Mg2+. Quanto aos ácidos graxos, 40,10% de AGS, 38,10% de AGM e 21,80% de AGP. Os cálculos indicaram valores significativos de ômegas, 3, 6, 7 e n-7. Em relação a ∑PUFAs/∑SFAs de 1,84 e ∑PUFAs (n-6/n-3) de 6,22, com um índice de IA de 0,50 e um IT de 0,93 e HH de 2,16. O 1,0 ±0,10 kg na gordura visceral de tambaqui pode ser avaliado como de alto valor nutricional, além de ser uma opção viável para extração do óleo e inclusão na ração animal.(AU)


Assuntos
Animais , Perciformes/fisiologia , Ácidos Graxos/análise , Compostos Inorgânicos/análise , Lipídeos/análise , Adipócitos , Valor Nutritivo
4.
Environ Manage ; 60(1): 30-40, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28405753

RESUMO

Nutrient enrichment in streams due to land use is increasing globally, reducing water quality and causing eutrophication of downstream fresh and coastal waters. In temperate developed countries, the intensive use of fertilizers in agriculture is a main driver of increasing nutrient concentrations, but high levels and fast rates of urbanization can be a predominant issue in some areas of the developing world. We investigated land use in the highly urbanized tropical State of Rio de Janeiro, Brazil. We collected total nitrogen, total phosphorus, and inorganic nutrient data from 35 independent watersheds distributed across the State and characterized land use at a riparian and entire watershed scales upstream from each sample station, using ArcGIS. We used regression models to explain land use influences on nutrient concentrations and to assess riparian protection relationships to water quality. We found that urban land use was the primary driver of nutrient concentration increases, independent of the scale of analyses and that urban land use was more concentrated in the riparian buffer of streams than in the entire watersheds. We also found significant thresholds that indicated strong increases in nutrient concentrations with modest increases in urbanization reaching maximum nutrient concentrations between 10 and 46% urban cover. These thresholds influenced calculation of reference nutrient concentrations, and ignoring them led to higher estimates of these concentrations. Lack of sewage treatment in concert with urban development in riparian zones apparently leads to the observation that modest increases in urban land use can cause large increases in nutrient concentrations.


Assuntos
Monitoramento Ambiental/métodos , Eutrofização , Rios/química , Urbanização/tendências , Poluentes Químicos da Água/análise , Agricultura , Brasil , Compostos Inorgânicos/análise , Modelos Teóricos , Nitrogênio/análise , Fósforo/análise , Clima Tropical
5.
Microbiol Res ; 188-189: 23-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27296959

RESUMO

Yucatán State is dominated by two kinds of soil, named "Black Leptosol" and "Red Leptosol", which are interwoven across the State. In this work, we analyzed the relation between the edaphic characteristics and the bacterial and fungal community structures in these two kinds of Leptosol. The results revealed that Black Leptosol (BlaS) had a higher content of calcium carbonates, organic matter, nitrogen, and phosphorus than Red Leptosol (RedS). The most outstanding difference in the bacterial community structure between BlaS and RedS was that while in BlaS Actinobacteria was the most abundant phylum (43.7%), followed by Acidobacteria (26.9%) and Proteobacteria (23.6%), in RedS the bacterial community was strongly dominated by Acidobacteria (83%). Two fungal phyla were identified in both kinds of soil; Ascomycota, with 77% in BlaS and 56% in RedS, and Basidiomycota, with 22% in RedS and only 0.67% in BlaS. The most relevant difference between the two fungal communities was that excepting for Fusarium sp., all the species they had were different. Thus, in contrast with bacterial communities, where most of the major OTUs were present in both kinds of soil, fungal communities appeared to be unique to each kind of Leptosol.


Assuntos
Bactérias/classificação , Bactérias/genética , Biota , Fungos/classificação , Fungos/genética , Microbiologia do Solo , Solo/química , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Compostos Inorgânicos/análise , México , Compostos Orgânicos/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
6.
Astrobiology ; 13(3): 294-302, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23406344

RESUMO

Early in its history, Earth's surface developed from an uninhabitable magma ocean to a place where life could emerge. The first organisms, lacking ion transporters, fixed the composition of their cradle environment in their intracellular fluid. Later, though life adapted and spread, it preserved some qualities of its initial environment within. Modern prokaryotes could thus provide insights into the conditions of early Earth and the requirements for the emergence of life. In this work, we constrain Earth's life-forming environment through detailed analysis of prokaryotic intracellular fluid. Rigorous assessment of the constraints placed on the early Earth environment by intracellular liquid will provide insight into the conditions of abiogenesis, with implications not only for our understanding of early Earth but also the formation of life elsewhere in the Universe.


Assuntos
Citoplasma/química , Meio Ambiente , Compostos Inorgânicos/análise , Origem da Vida , Atmosfera/química , Bactérias/citologia , Bactérias/metabolismo , Dióxido de Carbono/análise , Cátions , Elementos Químicos , Fontes Hidrotermais/química , Metano/análise , Modelos Teóricos , Oceanos e Mares , Água do Mar/química
7.
Microsc Res Tech ; 75(10): 1348-52, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22628243

RESUMO

The purpose of this study was to characterize the inorganic components and morphology of filler particles of conventional and self-adhesive, dual-curing, resin luting cements. The main components were identified by energy dispersive X-ray spectroscopy microanalysis (EDX), and filler particles were morphologically analyzed by scanning electron microscopy (SEM). Four resin cements were used in this study: two conventional resin cements (RelyX ARC/3M ESPE and Clearfil Esthetic Cement/Kuraray Medical) and two self-adhesive resin cements (RelyX Unicem/3M ESPE and Clearfil SA Luting/Kuraray Medical). The materials (n = 5) were manipulated according to manufacturers' instructions, immersed in organic solvents to eliminate the organic phase and observed under SEM/EDX. Although EDX measurements showed high amount of silicon for all cements, differences in elemental composition of materials tested were identified. RelyX ARC showed spherical and irregular particles, whereas other cements presented only irregular filler shape. In general, self-adhesive cements contained higher filler size than conventional resin luting cements. The differences in inorganic components and filler particles were observed between categories of luting material and among them. All resin cements contain silicon, however, other components varied among them.


Assuntos
Cimentos Dentários/química , Compostos Inorgânicos/análise , Cimentos de Resina/química , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos
8.
Chemosphere ; 88(5): 584-90, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22472096

RESUMO

The emission of volatile pollutants from the volcanic eruption of the Puyehue-Cordón Caulle complex (North Patagonia Andean Range) that started in June 4th, 2011, was investigated by bioindication means with the epyphytic fruticose lichen Usnea sp. The elemental composition of pooled samples made up with 10 lichen thalli were analysed by Instrumental Neutron Activation Analysis. Eleven sampling sites were selected within the impacted region at different distance from the volcanic source. Five sites were selected as they were already sampled in a previous study prior to the eruption. Two other new sampling sites were selected from outside the impacted zone to provide non-impacted baseline sites. The elements associated with the lichen incorporation of particulate matter (PM) of geological origin were identified by linear correlation with a geochemical tracer (Sm concentrations). The elements associated with PM uptake were Ce, Eu, Fe, Hf, La, Lu, Na, Nd, Sb, Sc, Se, Ta, Tb, Th, U, and Yb. Arsenic and Cs concentrations showed contributions exceeding the PM fraction in sites near the volcanic centre, also higher than the baseline concentrations, which could be associated with permanent emissions from the geothermal system of the Puyehue-Cordón Caulle complex. The lichen concentrations of Ba, Ca, Co, Hg, K, Rb, Sr, and Zn were not associated with the PM, not showing higher concentrations in the sites nearby the volcanic source or respect to the baseline values either. Therefore, there is no indication of the emission of volatile forms of these elements in the lichen records. The lichen records only identified Br volatile emissions associated with the Puyehue-Cordón Caulle complex eruption in 2011.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Poluentes Ambientais/química , Erupções Vulcânicas/análise , Compostos Inorgânicos/análise , Compostos Inorgânicos/química , Líquens/química , Material Particulado/análise , Material Particulado/química , Volatilização
9.
Indian J Med Res ; 135: 217-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22446864

RESUMO

BACKGROUND & OBJECTIVES: Concentric lamellar calcifications known as psammoma bodies (PB) are found in benign and malignant tumours. Whether or not the inorganic element concentrations in psammomas are similar to serous adenocarcinoma of the ovary and thyroid papillary cancer tissues has not yet been ascertained. We undertook this retrospective study to establish if there is any difference in the concentrations of inorganic ions found in psammomas in serous adenocarcinoma of the ovary, and those found in thyroid papillary cancer tissue. METHODS: PB samples from patients with adenocarcinoma of the ovary (n = 10) and with thyroid papillary cancer (n = 10) were analyzed through inductively-coupled plasma spectroscopy (ICP). RESULTS: There were no significant differences in the concentrations of inorganic elements in PB from thyroid papillary cancer than in those PB from ovarian cancer. INTERPRETATION & CONCLUSIONS: Differences in the concentrations of inorganic elements may be due to the variation in environmental pollution. Our study had limitation of small sample size. Our results suggest that some inorganic elements can participate in the origin of psammoma bodies.


Assuntos
Compostos Inorgânicos/análise , Íons/análise , Neoplasias Ovarianas/química , Neoplasias da Glândula Tireoide/química , Adenocarcinoma/química , Carcinoma , Carcinoma Papilar , Feminino , Humanos , Câncer Papilífero da Tireoide
10.
Microsc Res Tech ; 75(6): 758-65, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22213178

RESUMO

The purpose of this study was to compare the inorganic content and morphology of one nanofilled and one nanohybrid composite with one universal microhybrid composite. The Vickers hardness, degree of conversion and scanning electron microscope of the materials light-cured using LED unit were also investigated. One nanofilled (Filtek™ Supreme XT), one nanohybrid (TPH®(3)) and one universal microhybrid (Filtek™ Z-250) composite resins at color A(2) were used in this study. The samples were made in a metallic mould (4 mm in diameter and 2 mm in thickness). Their filler weight content was measured by thermogravimetric analysis (TG). The morphology of the filler particles was determined using scanning electron microscope equipped with a field emission gun (SEM-FEG). Vickers hardness and degree of conversion using FT-IR spectroscopy were measured. Filtek™ Z-250 (microhybrid) composite resin shows higher degree of conversion and hardness than those of Filtek™ Supreme XT (nanofilled) and TPH®(3) (nanohybrid) composites, respectively. The TPH(3)® (nanohybrid) composite exhibits by far the lowest mechanical property. Nanofilled composite resins show mechanical properties at least as good as those of universal hybrids and could thus be used for the same clinical indications as well as for anterior restorations due to their high aesthetic properties.


Assuntos
Resinas Compostas/química , Compostos Inorgânicos/análise , Nanoestruturas/análise , Microscopia Eletrônica de Varredura
11.
Rev. biol. trop ; Rev. biol. trop;59(4): 1869-1882, Dec. 2011. tab
Artigo em Inglês | LILACS | ID: lil-646558

RESUMO

During forest succession, litterfall nutrient fluxes increase significantly. The higher inputs of organic matter and nutrients through litterfall affects positively soil fertility and the species composition, which are essential components in forest restoration and management programs. In the present study, the input of nutrients to the forest soil via litterfall components was estimated for two sites of different development stages, in an early successional alluvial rain forest in Brazil. Litterfall returned to the soil, in kg/ha, ca. 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu and 11.2 Al, in the site where trees were more abundant and had higher values of basal area. In the other area, where trees where less abundant and values of basal area were comparatively low, litterfall returned <50% of those amounts to the forest soil, except for Al. The amount of Al that returned to the soil was similar in both areas due to the high contribution of Tibouchina pulchra (82% of Al returned). Comparatively, high proportion of three dominant native tree species (Myrsine coriacea, T. pulchra and Cecropia pachystachya) explained better litter nutrient use efficiency (mainly N and P) in the site with the least advanced successional stage. Although litterfall of these species show lower nutrient concentrations than the other tree species, their nutrient fluxes were high in both sites, indicating a certain independence from soil essential nutrients. Such feature of the native species is very advantageous and should be considered in forest restoration programs. Rev. Biol. Trop. 59 (4): 1869-1882. Epub 2011 December 01.


Durante la sucesión secundaria forestal, el flujo de nutrientes en la hojarasca se incrementa significativamente. Los altos ingresos de materia orgánica y nutrientes a través de la hojarasca afecta positivamente la fertilidad del suelo y la composición de especies, las cuales son componentes esenciales para programas de restauración forestal y de manejo. En el presente estudio, el ingreso de nutrientes a través de la hojarasca y sus componentes fueron estimados para dos sitios de una selva lluviosa atlántica aluvial en sucesión temprana. La cantidad anual de elementos que ingresan al suelo desde la vegetación más desarrollada (sitios con alta área basal y abundancia de árboles) fueron (en kg/ha): 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu y 11.2 Al. Menos de la mitad de esas cantidades fueron aportadas por la vegetación menos desarrollada, excepto para el Al. La cantidad de Al aportada a este sitio fue similar a la contribución de la vegetación más desarrollada, debido a la contribución de: Tibouchina pulchra (82% de todo el Al aportado). La eficiencia en el uso de nutrientes de la hojarasca (principalmente de N y P) de la vegetación menos desarrollada fue superior a la eficiencia de una más desarrollada, debido a la alta proporción de tres especies nativas dominantes (Myrsine coriacea, Tibouchina pulchra y Cecropia pachystachya) en la primera. Si bien la hojarasca de esas especies presenta menor concentración de nutrientes que las otras especies arbóreas, el flujo de nutrientes fue mayor (para ambos sitios), marcando una cierta independencia de los nutrientes esenciales del suelo. Las cantidades de esas especies deberían ser consideradas con mayor atención para su uso en programas de restauración forestal.


Assuntos
Biodegradação Ambiental , Folhas de Planta/metabolismo , Solo/química , Árvores/metabolismo , Brasil , Compostos Inorgânicos/análise , Compostos Orgânicos/análise , Fatores de Tempo , Clima Tropical , Árvores/crescimento & desenvolvimento
12.
Talanta ; 85(4): 1744-50, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21872013

RESUMO

It has been demonstrated that laser induced breakdown spectrometry (LIBS) can be used as an alternative method for the determination of macro (P, K, Ca, Mg) and micronutrients (B, Fe, Cu, Mn, Zn) in pellets of plant materials. However, information is required regarding the sample preparation for plant analysis by LIBS. In this work, methods involving cryogenic grinding and planetary ball milling were evaluated for leaves comminution before pellets preparation. The particle sizes were associated to chemical sample properties such as fiber and cellulose contents, as well as to pellets porosity and density. The pellets were ablated at 30 different sites by applying 25 laser pulses per site (Nd:YAG@1064 nm, 5 ns, 10 Hz, 25J cm(-2)). The plasma emission collected by lenses was directed through an optical fiber towards a high resolution echelle spectrometer equipped with an ICCD. Delay time and integration time gate were fixed at 2.0 and 4.5 µs, respectively. Experiments carried out with pellets of sugarcane, orange tree and soy leaves showed a significant effect of the plant species for choosing the most appropriate grinding conditions. By using ball milling with agate materials, 20 min grinding for orange tree and soy, and 60 min for sugarcane leaves led to particle size distributions generally lower than 75 µm. Cryogenic grinding yielded similar particle size distributions after 10 min for orange tree, 20 min for soy and 30 min for sugarcane leaves. There was up to 50% emission signal enhancement on LIBS measurements for most elements by improving particle size distribution and consequently the pellet porosity.


Assuntos
Métodos Analíticos de Preparação de Amostras/métodos , Lasers , Magnoliopsida/química , Análise Espectral/métodos , Compostos Inorgânicos/análise , Tamanho da Partícula , Folhas de Planta/química , Porosidade
13.
J Agric Food Chem ; 59(14): 7854-65, 2011 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-21671663

RESUMO

Our main goal was to investigate if robust chemical fingerprints could be developed for three Argentinean red wines based on organic, inorganic, and isotopic patterns, in relation to the regional soil composition. Soils and wines from three regions (Mendoza, San Juan, and Córdoba) and three varieties (Cabernet Sauvignon, Malbec, and Syrah) were collected. The phenolic profile was determined by HPLC-MS/MS and multielemental composition by ICP-MS; (87)Sr/(86)Sr and δ(13)C were determined by TIMS and IRMS, respectively. Chemometrics allowed robust differentiation between regions, wine varieties, and the same variety from different regions. Among phenolic compounds, resveratrol concentration was the most useful marker for wine differentiation, whereas Mg, K/Rb, Ca/Sr, and (87)Sr/(86)Sr were the main inorganic and isotopic parameters selected. Generalized Procrustes analysis (GPA) using two studied matrices (wine and soil) shows consensus between them and clear differences between studied areas. Finally, we applied a canonical correlation analysis, demonstrating significant correlation (r = 0.99; p < 0.001) between soil and wine composition. To our knowledge this is the first report combining independent variables, constructing a fingerprint including elemental composition, isotopic, and polyphenol patterns to differentiate wines, matching part of this fingerprint with the soil provenance.


Assuntos
Compostos Inorgânicos/análise , Compostos Orgânicos/análise , Solo/análise , Vitis/química , Vinho/análise , Argentina , Isótopos/análise , Controle de Qualidade
14.
Rev Biol Trop ; 59(4): 1869-82, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22208099

RESUMO

During forest succession, litterfall nutrient fluxes increase significantly. The higher inputs of organic matter and nutrients through litterfall affects positively soil fertility and the species composition, which are essential components in forest restoration and management programs. In the present study, the input of nutrients to the forest soil via litterfall components was estimated for two sites of different development stages, in an early successional alluvial rain forest in Brazil. Litterfall returned to the soil, in kg/ha, ca. 93 N, 79 Ca, 24 K, 15 Mg, 6 P, 1.7 Mn, 0.94 Fe, 0.18 Zn, 0.09 Cu and 11.2 Al, in the site where trees were more abundant and had higher values of basal area. In the other area, where trees where less abundant and values of basal area were comparatively low, litterfall returned < 50% of those amounts to the forest soil, except for Al. The amount of Al that returned to the soil was similar in both areas due to the high contribution of Tibouchina pulchra (82% of Al returned). Comparatively, high proportion of three dominant native tree species (Myrsine coriacea, T. pulchra and Cecropia pachystachya) explained better litter nutrient use efficiency (mainly N and P) in the site with the least advanced successional stage. Although litterfall of these species show lower nutrient concentrations than the other tree species, their nutrient fluxes were high in both sites, indicating a certain independence from soil essential nutrients. Such feature of the native species is very advantageous and should be considered in forest restoration programs.


Assuntos
Biodegradação Ambiental , Folhas de Planta/metabolismo , Solo/química , Árvores/metabolismo , Brasil , Compostos Inorgânicos/análise , Compostos Orgânicos/análise , Fatores de Tempo , Árvores/crescimento & desenvolvimento , Clima Tropical
15.
Anal Chim Acta ; 673(2): 200-5, 2010 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-20599036

RESUMO

The aim of this study was to develop a fast capillary electrophoresis method for the determination of inorganic cations (Na(+), K(+), Ca(2+), Mg(2+)) in biodiesel samples, using barium (Ba(2+)) as the internal standard. The running electrolyte was optimized through effective mobility curves in order to select the co-ion and Peakmaster software was used to determine electromigration dispersion and buffer capacity. The optimum background electrolyte was composed of 10 mmol L(-1) imidazole and 40 mmol L(-1) of acetic acid. Separation was conducted in a fused-silica capillary (32 cm total length and 23.5 cm effective length, 50 microm I.D.), with indirect UV detection at 214 nm. The migration time was only 36 s. In order to obtain the optimized conditions for extraction, a fractional factorial experimental design was used. The variables investigated were biodiesel mass, pH, extractant volume, agitation and sonication time. The optimum conditions were: biodiesel mass of 200 mg, extractant volume of 200 microL and agitation of 20 min. The method is characterized by good linearity in the concentration range of 0.5-20 mg kg(-1) (r>0.999), limit of detection was equal to 0.3 mg kg(-1), inter-day precision was equal to 1.88% and recovery in the range of 88.0-120%. The developed method was successfully applied to the determination of cations in biodiesel samples.


Assuntos
Biocombustíveis/análise , Eletroforese Capilar/métodos , Compostos Inorgânicos/análise , Cálcio/análise , Eletrólitos/química , Magnésio/análise , Potássio/análise , Sódio/análise , Espectrofotometria Ultravioleta
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 77(1): 59-63, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20547096

RESUMO

Details on how fluoride interferes in enamel mineralization are still controversial. Therefore, this study aimed at analyzing the organic contents of fluorosis-affected teeth using Fourier Transformation Infrared spectroscopy. To this end, 10 male Wistar rats were divided into two groups: one received 45 ppm fluoride in distilled water for 60 days; the other received distilled water only. Then, the lower incisors were removed and prepared for analysis by two FTIR techniques namely, transmission and micro-ATR. For the first technique, the enamel was powdered, whereas in the second case one fluorotic incisor was cut longitudinally for micro-ATR. Using transmission and powdered samples, FTIR showed a higher C-H content in the fluorotic enamel compared with control enamel (p<0.05, n=4 in the flurotic, and n=5 in the control group). Results from the micro-ATR-FTIR spectroscopic analysis on one longitudinally cut incisor carried out at six points reveal a higher C-H bond content at the surface of the enamel, with values decreasing toward the dentine-enamel junction, and reaching the lowest values at the subsuperficial enamel. These results agree with the morphological data, which indicate that in the rat incisor the fluorotic lesion is superficial, rather than subsuperficial, as in the case of human enamel. The results also suggest that the increased C-H bond content may extend toward the more basal enamel (intraosseous), indicating that fluorotic enamel may intrinsically contain more protein. Finally, particularly when coupled to ATR, FTIR is a suitable tool to study the rat incisor enamel, which is a largely used model of normal and abnormal amelogenesis. Further studies along this line may definitely answer some questions regarding protein content in fluorotic enamel as well as their origin.


Assuntos
Fluorose Dentária/metabolismo , Compostos Inorgânicos/metabolismo , Compostos Orgânicos/metabolismo , Animais , Esmalte Dentário/química , Incisivo , Compostos Inorgânicos/análise , Masculino , Compostos Orgânicos/análise , Fosfatos/metabolismo , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier
17.
Mar Pollut Bull ; 60(1): 123-30, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19783258

RESUMO

Ensenada Harbor is one of the most important ports of Mexico. Anthropogenic activities have affected the area over several decades, leading to the accumulation of contaminants in its sediments, which eventually are re-suspended into the water column. In spite of water treatment of the tributaries that discharge into the Ensenada Harbor, the water circulation patterns of the harbor, which consist of closed eddies in the northern and southeastern sector, favor the accumulation of those contaminants and hinder exchange with adjacent seawater. Samples collected in October of 2005 registered 63 microM total inorganic nitrogen and 280 mg/L of COD, confirming that this is a highly contaminated environment when compared with other water bodies of North America. Such concentrations can be lowered up to 80% by using a wave energy pumping system that demonstrates the possibility to gradually dilute these contaminants and rehabilitate the Ensenada Harbor.


Assuntos
Monitoramento Ambiental , Recuperação e Remediação Ambiental , Sedimentos Geológicos/análise , Água do Mar/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Abastecimento de Água/análise , Geografia , Sedimentos Geológicos/química , Compostos Inorgânicos/análise , México , Nitrogênio/análise , Oxigênio/análise , Fósforo/análise , Controle de Qualidade , Medição de Risco , Fatores de Tempo , Clima Tropical , Abastecimento de Água/normas
18.
Braz Dent J ; 21(6): 520-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21271042

RESUMO

The aim of this study was to determine quantitatively and qualitatively the inorganic particle fraction of commercially available dental elastomers. The inorganic volumetric fraction of two addition silicones (Reprosil Putty/Fluid and Flexitime Easy Putty/Fluid), three condensation silicones (Clonage Putty/Fluid, Optosil Confort/Xantopren VL and Silon APS Putty/Fluid), one polyether (Impregum Soft Light Body) and one polysulfide (Permlastic Light Body) was accessed by weighing a previously determined mass of each material in water before and after burning samples at 600 ºC, during 3 h. Unsettled material samples were soaked in acetone and chloroform for removal of the organic portion. The remaining filler particles were sputter-coated with gold evaluation of their morphology and size, under scanning electron microscopy (SEM). Flexitime Easy Putty was the material with the highest results for volumetric particle fraction, while Impregum Soft had the lowest values. Silon 2 APS Fluid presented the lowest mean filler size values, while Clonage Putty had the highest values. SEM micrographs of the inorganic particles showed several morphologies - lathe-cut, spherical, spherical-like, sticks, and sticks mixed to lathe-cut powder. The results of this study revealed differences in particle characteristics among the elastometic materials that could lead to different results when testing mechanical properties.


Assuntos
Materiais para Moldagem Odontológica/química , Análise do Estresse Dentário , Elastômeros/química , Compostos Inorgânicos/análise , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polivinil , Resinas Sintéticas/química , Siloxanas/química , Espectrometria por Raios X , Sulfetos/química , Viscosidade
19.
Braz. dent. j ; Braz. dent. j;21(6): 520-527, 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-572298

RESUMO

The aim of this study was to determine quantitatively and qualitatively the inorganic particle fraction of commercially available dental elastomers. The inorganic volumetric fraction of two addition silicones (Reprosil Putty/Fluid and Flexitime Easy Putty/Fluid), three condensation silicones (Clonage Putty/Fluid, Optosil Confort/Xantopren VL and Silon APS Putty/Fluid), one polyether (Impregum Soft Light Body) and one polysulfide (Permlastic Light Body) was accessed by weighing a previously determined mass of each material in water before and after burning samples at 600ºC, during 3 h. Unsettled material samples were soaked in acetone and chloroform for removal of tthe organic portion. The remaining filler particles were sputter-coated with gold evaluation of their morphology and size, under scanning electron microscopy (SEM). Flexitime Easy Putty was the material with the highest results for volumetric particle fraction, while Impregum Soft had the lowest values. Silon 2 APS Fluid presented the lowest mean filler size values, while Clonage Putty had the highest values. SEM micrographs of the inorganic particles showed several morphologies - lathe-cut, spherical, spherical-like, sticks, and sticks mixed to lathe-cut powder. The results of this study revealed differences in particle characteristics among the elastometic materials that could lead to different results when testing mechanical properties.


O objetivo desse estudo foi determinar quantitativamente e qualitativamente a fração de partículas inorgânicas de elastômeros dentais disponíveis comercialmente. A fração volumétrica de dois silicones por adição (Reprosil Denso/Fluído e Flexitime Denso/Fluído), três silicones por condensação (Clonage Denso/Fluído, Optosil/Xantopren, e Silon 2 APS Denso/Fluído), um poliéter (Impregum Soft Light) e um polissulfeto (Permlastic Light Body) foi determinada pela pesagem prévia de uma determinada massa de cada material em água antes e após a queima das amostras a 600ºC, por 3 h. Amostras de material não polimerizado foram imersas em acetona e clorofórmio para a remoção da parte orgânica. As partículas de carga remanescentes foram cobertas com uma camada de ouro para avaliação da sua morfologia e tamanho, em microscopia eletrônica de varredura. O material Flexitime Denso foi o material com maior fração volumétrica de partículas de carga, enquanto que o Impregum teve menor fração volumétrica. Silon 2 APS Fluído apresentou partículas de carga de menor tamanho, enquanto que o Clonage Denso apresentou as maiores partículas. A observação em MEV. mostrou partículas de carga com vários tipos de morfologia (esféricas, irregulares, semi-esféricas, retangulares e mistura de retangulares/irregulares). Os resultados desse estudo mostraram diferenças nas partículas de carga dos materiais, as quais podem levar a diferentes resultados em suas propriedades mecânicas.


Assuntos
Análise do Estresse Dentário , Materiais para Moldagem Odontológica/química , Elastômeros/química , Compostos Inorgânicos/análise , Teste de Materiais , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Polivinil , Resinas Sintéticas/química , Espectrometria por Raios X , Siloxanas/química , Sulfetos/química , Viscosidade
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