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1.
Article | IMSEAR | ID: sea-220581

ABSTRACT

The elemental analysis of packed food items which is collected in Debre Tabor markets, Ethiopia namely Pasta, Macaroni, cookies, biscuit, wheat bread, white teff injera, Red teff injera, barley so, barleycorn and maiz bread samples were carried out using EDX spectrometer. An X-ray beam was used to excite each sample and spectra were recorded with a high-resolution Si(Li) detector. The data analysis was carried out by software. Trace elements P, K, Na, Cl, Mg, Ca, Fe, Al and Zn were estimated, and elemental concentrations were determined. To get the exact results of the present study the analysis repeats three times.

2.
Braz. arch. biol. technol ; 65: e22210592, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1364446

ABSTRACT

Abstract The sewage sludge (SS) use in agriculture has been limited by the Brazilian legislation to a few situations, mainly as a precautionary measure due to inorganic pollutants and pathogens. Thus, a large amount of SS has been accumulated in landfills, with no prospect of use, generating great concern for governments and society. Thermal treatment via pyrolysis has stood out as an option for SS recycling, transforming it into a carbon-rich product known as SS biochar (SSB). Biochar from SS showed good potential to be used for agricultural and environmental purposes. The present study aimed to evaluate the influence of pyrolysis at 300°C on the physical, chemical, morphological and mineralogical characteristics of SSB. In general, pyrolysis increased total carbon, total nitrogen, macro and micronutrient contents, except potassium. Pyrolysis also increased heavy metals (HMs) concentration in SSB. However, HMs values remained below the maximum limits allowed according to the legislation on SS agricultural use. X-ray analysis showed that both SS and SSB present silica (SiO2) as the main mineral. Pyrolysis also increased the SS surface area (SA) and porosity. In general, results of the present study prove showed that pyrolysis is a technological alternative to enable SS use as a sustainable input in agriculture.

3.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1385772

ABSTRACT

RESUMEN: Los instrumentos rotatorios utilizados en el tratamiento de conductos dentales necesitan cumplir con ciertas características físicas que le confieran un uso correcto, adecuado y seguro para su uso clínico. En el mercado comercial existen una serie de instrumentos importados que dejan en duda la autenticidad de estos debido a sus bajos costos. En este estudio evaluamos física, química y morfológicamente dos kits de instrumentos rotatorios Protaper universal (Dentsply) mediante análisis de MEB, EDX, microdureza y EDS. Uno de los kits (grupo 1) se adquirió directamente de la casa comercial y otro kit importado que a simple vista no parecía cumplir con los estándares de calidad de un correcto empaquetado (grupo 2). En el análisis de MEB se observaron características morfológicas muy diferentes entre ambos kits, el grupo 2 presentó diversas irregularidades en la superficie de las limas, sin embargo, en el EDS no se encontró diferencia alguna. En cuanto al análisis de microdureza se observó una estadística estadísticamente significativa y en el EDS se observaron mayores picos de intensidad en cuanto a la aleación de Ni-Ti en el grupo 2. Estos resultados sugieren que existen instrumentos rotatorios importados que a pesar de su bajo costo pueden presentar ciertas características muy similares a los kits auténticos, sin embargo, física y químicamente pueden resultar en un riesgo para su uso clínico debido a la diferencia entre estos.


ABSTRACT: Rotatory files are instruments used in the treatment of dental canals roots. These instruments need to comply with certain physical characteristics for a correct, adequate and safe use for clinical use. In the commercial market there are a series of imported instruments that cast doubt on their authenticity due to their low costs. In this study we physically, chemically and morphologically evaluated two Protaper universal rotary instrument kits (Dentsply) using SEM, EDX, microhardness and EDS analysis. One of the kits (group 1) was purchased directly from the commercial house and another imported kit that a simple view did not seem to meet the quality standards of a correct packaging (group 2). In the SEM analysis, very different morphological characteristics were observed between both kits, group 2 presented various irregularities on the surface of the files, however, no difference was found in the EDS. Regarding the microhardness analysis, a statistically significant statistic was observed and in the EDS, higher intensity peaks were observed in terms of the Ni-Ti alloy in group 2. These results suggest that there are imported rotary instruments that despite their low cost can present characteristics very similar to authentic kits, however, physically and chemically they can result in a risk for their clinical use due to the difference between them.

4.
Braz. arch. biol. technol ; 59: e16160111, 2016. tab, graf
Article in English | LILACS | ID: biblio-951380

ABSTRACT

ABSTRACT Twenty-seven bottled mineral waters from local markets in Curitiba, State of Paraná, Brazil were analyzed for a number of constituents, including: pH, conductivity, total dissolved solids, hardness, HCO3 - and CO 3 2-, as well as Ca2+, Mg2+, Na+, K+, NH4 + , F-, Cl-, NO3 -, NO2 - and SO4 2- by ion chromatography (IC); Al, Ba, Cd, Cr, Cu, Fe, Li, Mn, Ni, Sr, V and Zn by inductively coupled plasma optical emission spectrometry (ICP OES); Hg by cold vapor generation-ICP OES and As, Pb, Sb and Se by ICP-mass spectrometry (ICP-MS). The obtained limits of quantitation (LOQ) were adequate for the determination of all analytes using the various analytical techniques. Results for the analysis of AccuStandard certified reference materials QCS-01-5, QCS-02-R1-5 and TCLP-02-1 as well as spike recoveries to samples show acceptable values, within 90-111 % of expected concentrations with relative standard deviations below 10 %, demonstrating the accuracy of the determinations. Both NO2 - and NO 3 - were above the maximum limits set by Brazilian legislation in two samples, indicating a microbiological contamination. One imported sample presented As (6.1 ± 0.2 µg L-1) near the maximum limit (10 µg L-1) while all other elements of interest were below the values specified by Brazilian legislation. Principal component analysis revealed that four imported samples and one from the Minas Gerais State have the highest mineral concentrations.

5.
Asian Pacific Journal of Tropical Biomedicine ; (12): 50-54, 2016.
Article in Chinese | WPRIM | ID: wpr-950810

ABSTRACT

Objective: To investigate the elemental composition of the leaves and flowers of Catharanthus roseus (C. roseus) due to the plant's wide application in the indigenous medicinal system and its chemical constituents' importance. Methods: The atomic absorption spectrophotometer was used for quantitative analysis of various elements. Results: Total 13 important elements were analyzed in leaves and flowers of C. roseus. Results indicated the presence of Na, K, Ca, Mg, Cr, Fe, Zn, Al, Cu, Ni, Pb, Cd and Mn in both leaves and flowers. The most important finding of the work was that, leaves of C. roseus showed high concentration of all elements except K and Zn while flowers of C. roseus showed higher concentration of K and Zn. Conclusions: The elemental composition in both leaves and flowers of C. roseus were found to be different. Therefore, different parts of this medicinal plant are enriched in some micro and macro nutrients like Fe, Ca, Na, K, Zn, which are very important for biological metabolic system as well as human health.

6.
Rev. biol. trop ; 63(2): 385-399, Apr.-Jun. 2015. ilus, graf, mapas, tab
Article in Spanish | LILACS, SaludCR | ID: lil-764974

ABSTRACT

Aratus pisonii is an abundant Neotropical mangrove crab that forages on fresh leaf tissue in the canopy and lives in a wide spectrum of habitats. It presents great plasticity in some aspects of its life history becoming an excellent subject for comparative studies. The purpose of this study was to investigate possible reproductive variations among populations of this crab in mangroves with different levels of structural development, and explore the direct and indirect effects of environmental variables on reproductive investment. The study was conducted during the rainy season of 2003 and 2004, in North Western Venezuela. Fecundity (number of eggs/female), dry weight of egg mass (PSH) and egg quality (C/Neggs) were evaluated in five populations of this species, in mangroves under different environmental conditions (estuarine, marine, hypersaline) and diverse degrees of structural development (arboreal, arbustive, scrub). Reproductive output (Ro) was obtained by the ratio Ro=PSH/dry body weight (PSC); other estimations of Ro were tested: Ro1=PSH/carapace length (CL), Ro2=fecundity/CL. A path analysis was used to explore causal relationships between environmental and morphological variables and reproductive investment (PSH, fecundity). Fecundity ranged from 6 463±831 eggs (Mean±SE) in the hypersaline arbustive mangrove to a maximum of 24 584±2 393 eggs in estuarine arboreal mangrove, which presents the greatest structural development. The reproductive output of females showed significant differences among mangroves, with the highest values of Ro1, Ro2 in the estuarine mangrove females. The results of the path analysis indicated a multicausal effect of morphological and environmental variables; in particular, the salinity showed the greatest influence on fecundity and PSH. The condition of the estuarine mangrove forests with lower salinity and higher structural development involving higher quality of mangrove leaves and a wider range of potential resources, may explain the higher reproductive output of females observed in this habitat. Rev. Biol. Trop. 63 (2): 385-399. Epub 2015 June 01.


Aratus pisonii es un cangrejo abundante de los manglares del Neotrópico, que forrajea sobre el tejido foliar fresco del dosel y vive en una amplia variedad de hábitats. Presenta una gran plasticidad en algunos aspectos de su historia de vida, convirtiéndose en un excelente sujeto para estudios comparativos. El propósito de este estudio fue investigar las posibles variaciones reproductivas entre las poblaciones de este cangrejo en manglares con diferentes niveles de desarrollo estructural, y explorar los efectos directos e indirectos de las variables ambientales sobre la inversión reproductiva. El estudio se realizó durante la temporada de lluvias 2003 y 2004, en la región Noroccidental de Venezuela. Se evaluaron la fecundidad (número de huevos/hembra), el peso seco de la masa de huevos (PSH) y la calidad del huevo (C/Nhuevos) en cinco poblaciones de esta especie, que viven en manglares bajo diferentes condiciones ambientales (estuarinos, marinos, hipersalinos) y diferente grados de desarrollo estructural (arbóreo, arbustivo, achaparrado). El rendimiento reproductivo (Ro) se obtuvo por la relación Ro=PSH/peso seco del cuerpo (PSC); se probaron otras estimaciones de Ro: Ro1=PSH/longitud del caparazón (LC), Ro2=fecundidad/LC. Se utilizó un análisis de rutas para explorar las relaciones causales entre las variables ambientales y morfológicas con la inversión reproductiva (PSH, fecundidad). La fecundidad varió de 6 463±831 huevos (media±ES) en el manglar arbustivo hipersalino, hasta un máximo de 24 584±2 393 huevos en el manglar arbóreo estuarino, que presentó el mayor desarrollo estructural. El rendimiento reproductivo de las hembras mostró diferencias significativas entre manglares, encontrándose los más altos valores de Ro1, Ro2 en las hembras de manglar estuarino. Los resultados del análisis de rutas indicaron un efecto multicausal de variables morfológicas y ambientales; en particular, la salinidad mostró la mayor influencia sobre la fecundidad y el PSH. La condición del manglar estuarino con menor salinidad y mayor desarrollo estructural, que de acuerdo con estudios anteriores supone una mayor calidad de las hojas de mangle y una mayor variedad de recursos potenciales, puede explicar la mayor inversión reproductiva observada en las hembras de este hábitat.


Subject(s)
Reproduction , Decapoda/classification , Crustacea/classification , Venezuela
7.
Rev. dent. press ortodon. ortopedi. facial ; 13(3): 85-96, maio-jun. 2008. ilus, tab
Article in Portuguese | LILACS | ID: lil-484628

ABSTRACT

OBJETIVO: avaliar a composição química e rugosidade do fundo do slot de 90 braquetes metálicos divididos em 9 grupos: grupo 1- aço inoxidável (Equilibrium 2 - Dentaurum); grupo 2 - titânio (Equilibrium ti - Dentaurum); grupo 3- cromo-cobalto (Topic- Dentaurum); grupo 4 - aço inoxidável (Standard -TP Orthodontics); grupo 5 - aço inoxidável (Serie light - American Orthodontics); grupo 6 - aço inoxidável (Kirium Line - Abzil Lancer); grupo 7 - aço inoxidável livre de níquel (Monobloc - Morelli); grupo 8 - aço inoxidável (Convencional- Morelli) e grupo 9 - aço inoxidável livre de níquel (Monobloc Golden - Morelli). METODOLOGIA: a composição química foi analisada pela Espectroscopia de Energia Dispersiva. A avaliação qualitativa do fundo do slot foi realizada através do MEV classificada de 0 a 8, correspondente às características da superfície. RESULTADOS: composição química - grupo 1 = titânio puro; grupo 9 = recoberto por nitreto de titânio em 99,48 por cento; grupo 3 = cromo-cobalto; grupo 8 = aço inoxidável livre de níquel. Os demais grupos são compostos de aço inoxidável. Avaliação da superfície - grupo 1 = valor 2 (superfície mais polida); grupos 2, 5 e 7 = valor 3 (aspecto de polimento); grupos 3, 8 e 9 = valor 6 (menor polimento); grupo 4 = valor 6,5 (maior rugosidade) e o grupo 6 = valor 5 (características intermediárias de polimento). CONCLUSÕES: os braquetes metálicos são compostos de diferentes ligas e estão disponíveis com baixo conteúdo ou ausência de níquel. Os braquetes de titânio apresentaram polimento semelhante aos de aço inoxidável, porém os recobertos por nitreto de titânio e os de cromo-cobalto mostraram superfície mais irregular ou menos polida.


AIM: To evaluate the elemental composition and the slot roughness of 90 metallic brackets divided into 9 groups: group 1 - stainless steel (Equilibrium 2 - Dentaurum); group 2 - titanium (Equilibrium ti - Dentaurum); group 3 - chromium-cobalt (Topic - Dentaurum); group 4 - stainless steel (Standard - TP Orthodontics); group 5 - stainless steel (Serie light - American Orthodontics); group 6 - stainless steel (Kirium Line - Abzil Lancer); group 7 - stainless steel (Monobloc - Morelli); group 8 - stainless steel (Standard - Morelli) and group 9 - stainless steel (Monobloc Golden - Morelli). METHODS: Elemental composition was evaluated using the Spectroscopy of Dispersive Energy. The qualitative slot surface evaluation was assessed using a 500X scanning electron microscope. The microphotography was classified according to surface characteristics in 0-8 values. RESULTS: Elemental composition - group 1 = 100 percent titanium alloy; group 9 = 99,48 percent of titanium nitride coated. Group 3 = cobalt-chromium alloy; Group 8 = nickel free stainless steel alloy; other groups stainless steel alloy. Surface evaluation - Group 1 = value 2 (smoothest surface); Groups 2, 5 and 7 =value 3 (smooth surface); Groups 3, 8 and 9 showed value 6 (roughness surface); Group 4 = value 6,5 (the most roughness and irregular surface); and Group 6 has intermediate characteristics among the groups, with value 5. CONCLUSIONS: Metallic brackets were composed of different alloys and they were available with a small percentage or no nickel. The surface roughness was similar for both titanium and stainless steel, however the titanium nitride coated and cobalt-chromium showed an irregular and rough surface.


Subject(s)
Braces , Materials Testing , Orthodontic Wires
8.
Acta amaz ; 37(1): 91-98, 2007. graf, mapas, tab
Article in Portuguese | LILACS | ID: lil-459255

ABSTRACT

Os solos da Amazônia que possuem horizonte A antrópico (Au) apresentam elevada fertilidade natural geralmente atribuída ao teor elevado de matéria orgânica e à sua elevada reatividade. Neste estudo foram quantificadas as substâncias húmicas e caracterizados os ácidos húmicos (AH) extraídos da camada 0-20 cm de solos com horizonte Au do estado do Amazonas (Terra Preta de índio) sob floresta e cultivo agrícola. Também foram investigadas amostras de solos adjacentes sem o horizonte antrópico. A caracterização dos AH foi realizada através de análise termogravimétrica, análise da composição elementar e quantificação dos grupos funcionais (total, carboxílica e fenólica). Os horizontes A de solos antropogênicos apresentaram maior teor de carbono total, comparados aos de solos adjacentes. Entre as frações húmicas, a mais abundante foi a humina. A fração de ácidos húmicos (AH) foi a dominante das frações alcalino-solúveis nos solos estudados. Os AH dos solos antropogênicos tanto sob floresta como sob cultivo agrícola apresentaram maior grau de humificação quando comparados aos AH dos solos sem o horizonte Au. O cultivo agrícola também teve efeito na estabilidade e reatividade dos AH nos solos antropogênicos.


Amazonian dark earth soils that have anthropogenic A horizon (Au) present high natural fertility usually attributed to their high organic matter content and to their higher reactivity. In this study humic substances were quantified and the humic acids (HA) extracted from the 0-20 cm layer of Amazonian dark earth soils (Terra Preta do índio) under forest and agricultural use were characterized. Adjacent soils with no Au horizon were also investigated. The HA were characterized through the thermogravimetric analysis, elemental composition analysis and characterization of functional groups (total, carboxylic, and phenolic). The A horizon of the anthropogenic soils presented higher total carbon level compared to adjacent soils. Among the humic fractions, the humin was the most abundant. The humic acid fraction (HA) was the dominant among the alkaline soluble fractions. The humic acids of the anthropogenic soils, both under forest and cultivation, showed higher humification degree compared to the non-anthropogenic soils. The agricultural cultivation affected the humic acids stability and reactivity in the anthropogenic soils.


Subject(s)
Soil , Thermogravimetry , Amazonian Ecosystem , Acidity
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