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Microwave induced plasma optical emission spectrometry (MIP OES) was employed to determine the concentrations of macro and micronutrients (Ba, Ca, Cu, Fe, K, Mg, Mn and Na) in products derived from sugarcane: sugars (refined, crystal, demerara and brown) and derived products (molasses and brown sugar candy) produced in the southern region of Brazil. The sample preparation was performed by acid decomposition with a reflux system under optimized conditions: 1000 mg of sample and 5.0 mL of concentrated nitric acid for 4 hours at 150 °C and addition of 1.0 mL of hydrogen peroxide. At the end we obtained a procedure that provides analytical solutions in accordance with the established parameters of acidity and dissolved solids as per the MIP OES spectrometer manufacturer's recommendations. The accuracy was evaluated by the analyte addition tests (80 to 119%). The limits of detection, in mg kg−1, were 0.03 (Ba); 0.03 (Ca); 0.04 (Cu); 0.08 (Fe); 0.18 (K); 0.03 (Mg); 0.02 (Mn) and 0.26 (Na). The concentrations of the analytes in the different samples varied according to the degree of processing, since higher values appeared for the less processed samples, i.e. brown sugar, molasses and brown sugar candy.

Large-area and dense arrays of nanometric scale structures are commonly fabricated for several applications. The characterisation of sub-micron structures (below 1 μm) at a large scale as well as the related data analysis are challenging tasks. Here, we present a method to address the image acquisition, the data extraction and the data analysis, applied to the evaluation of the uniformity of nanometric structures in a silicon master. Automated routines for both high and low magnification Scanning Electron Microscope (SEM) imaging have been successfully developed. SEM images have been automatically acquired by scripting routines, which collect large amounts of images of the nanometric structures covering multiple regions of the wafer in a few hours. Geometric parameters of the nanometric structures such as diameter, period and height have been extracted from the raw images using the developed image processing scripts. Finally, the data extracted from more than 4800 images acquired with three different characterisation scripts (1600 images for each study) have been analysed and plotted according to their position in the wafer.

This work presents a study involving the determination of Cd, Cr and Pb in ceramic tableware by graphite furnace atomic absorption spectrometry (GF AAS) using a simple and practical slurry sampling...

The present study provides information about the total concentration and bioaccessible fraction of metals Al, Ba, Bi, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Pb, Ti and Zn in nine different infant cereal samples. An in vitro digestion method was employed to evaluate the bioaccessibility. The determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES). The bioaccessibility varied according to the type of infant cereal sample. The values of bioaccessible fraction (minimum and maximum) for Cu, Fe, Mn, Pb and Zn were 24–68, 1–10, 7–58, 24–100 and 1–7% of the total concentration, respectively. Al and Ti presented bioaccessibility in only two samples: 6% in the multicereal A and 14% in the rice and oat cereal B, respectively. The concentration of Ba, Bi, Cd, and Cr was below the limit of detection for the bioaccessibility method. The obtained concentrations were lower than the daily recommended intake for essential and toxic elements, with exception of Pb in the rice and oat A sample.

Traditional chocolate and whole-meal flour breakfast cereals were analyzed to determine the total concentrations and bioaccessibilities of some elements. For the total concentration, the samples were prepared by microwave digestion. In addition, certified reference materials were used to verify the accuracy of the method, which was 82–106% for the analytes. Great variation in the concentrations was observed, possibly due to the raw materials used to produce the cereals. For the bioaccessibility study, an in vitro digestion method was used, and the accuracy was verified by the addition and recovery method. Cu, Fe, Mn, and Zn had detectable bioaccessibilities from 37% to 47%, 1% to 41%, 8% to 61%, and 4% to 24% of the total concentrations, respectively. Aluminum, Ba, and Mo had concentrations below the limit of quantification. Therefore, breakfast cereals complement a healthy diet, since some essential elements have high bioaccessibilities.

info:eu-repo/grantAgreement/EC/H2020/734834/EU FCT/MEC (UIDB/50006/2020). PhD grant SFRH/BD/139171/2018 from FCT/MCTES. We are very grateful to Dr. Carlos Pinheiro and Ynvisible company for discussions and assistance in the assembly of the electrochromic devices. We report the use of films of poly(3-hexylthiophene-2,5-diyl) nanoparticles (P3HT-NPs) prepared with the reprecipitation method employing water as solvent in the absence of surfactants for solid-state electrochromic devices (ECDs) and prove that these displays present enhanced properties when compared to similar ECDs with thin films deposited from chloroform. Films of differently sized nanoparticles (100 to 400 nm) were prepared and spray-coated on flexible PET-ITO substrates and tested for electrochromic properties. ECDs with switching times (t(90)) of 4 s were obtained using P3HT-NPs with a diameter of 100 nm, while those built using P3HT thin film presented longer switching speeds over 13 s for reduction (bleached to colored state). Additionally, the devices were subjected to 1000 cycles using -1.5 V/1.5 V, and the displays using P3HT 100 nm NPs presented higher transmittances (Delta(T) = +/- 20%) when compared with devices with P3HT thin film due to a more efficient oxidation step. Our data show that the availability of colloidal nanoparticles made of conjugated polymers deposited from water is an environmentally sustainable strategy leading to electrochromic devices with improved properties. authorsversion published

This work describes the analysis of different chicken tissues (gizzard, heart, and liver) both raw and cooked with seasonings in different types of cooking pots (iron pot, , aluminum pot and hammered aluminum pot) commonly used in Brazil. The samples were decomposed using microwave-assisted digestion with diluted nitric acid; and the contents of Al, Ca, Cu, Fe, Mn and Ni were determined using Microwave Induced Plasma Optical Emission Spectrometry (MIP OES). The Fe content was also determined by Flame Atomic Absorption Spectrometry, and the comparison showed good accuracy of the method. The limits of quantification were below 0.011 mg kg-1, showing adequate detectability. Cooking in the different pots increased the ash and protein contents as well as decreased the moisture content. Box-plot and Principal Components Analysis showed that Ca and Fe contents present the largest variations in the samples, followed by Al and moisture. The variables Al, Cu, Mn, Ni, ash, and protein presented similar behavior after cooking in all different pots. In addition, liver cooked in both iron and hammered aluminum pots presented similar Fe contents, while gizzard and heart showed similar Ca contents. Resumo Este trabalho descreve a análise de tecidos comestíveis de frango como coração, fígado e moela, crus e cozidos com temperos em diferentes panelas (panela de ferro, panela de alumínio e panela de alumínio batido) comumente utilizadas no Brasil. A digestão ácida assistida por radiação micro-ondas, com utilização de ácido nítrico diluído, foi empregada para decomposição das amostras. Os teores dos elementos metálicos Al, Ca, Cu, Fe, Mn e Ni foram determinados por Espectrometria de Emissão Óptica com Plasma Induzido por Micro-ondas. A comparação dos teores de Fe obtidos também por Espectrometria de Absorção Atômica em Chama mostrou uma boa exatidão do método. Os limites de quantificação para os analitos avaliados ficaram abaixo de 0,011 mg kg-1, mostrando detectabilidade adequada. As cocções das amostras nas diferentes panelas utilizadas promoveram um aumento dos teores de cinzas e proteínas e uma diminuição dos teores de umidade. A Análise de Componentes Principais e os diagramas de caixa mostraram que as variáveis Ca e Fe apresentaram as maiores variações entre as amostras, seguidas pelas variáveis Al e umidade. As variáveis Al, Cu, Mn, Ni, cinzas e proteínas apresentaram comportamento semelhante após a cocção nos três tipos de panela empregados. A amostra de fígado cozida tanto na panela de ferro quanto na panela de alumínio batido apresentou teores similares de Fe, enquanto as amostras de coração e moela apresentaram teores similares de Ca após cocção nas mesmas panelas.

The quantification of the total concentration and an in vitro digestion method was used to evaluate the bioaccessibility of elements in berries. The results for the total concentration of Al, Ba, Ca, Cu, Fe, K, Mg, Mn and Zn show the values (expressed as concentration range): 1.2–8.3; −1 , respectively, and the bioaccessibility values are approximately 10, 74, 41, 9, 34 and 18% of the total concentration for Al, Ba, Cu, Fe, Mn and Zn, respectively. These results show that Ba has the greatest value for bioaccessibility and that almost half of Cu and Mn present in the fruit is bioaccessible, while the values for Al, Fe and Zn are much lower. It was also verified that the bioaccessibility varies with the samples, depending on their polyphenol composition. The poor bioaccessibility of Zn and Fe is expected because these elements tend to form insoluble compounds with phytates and fibers present in fruits, while Cu and Mn may form metal-phytate complexes that are more soluble in the gastrointestinal tract.

The present work describes a sample preparation method using acid decomposition in reflux system for the determination of Hg on xanthan gum samples by cold vapor atomic absorption spectrometry (CV AAS). The best conditions of sample preparation method were optimized. This procedure proved to be safe for the quantification of this analyte, because no significant losses of Hg by volatilization, which is due to the efficient reflux system. The limits of detection and quantification were 0.0049 and 0.0163 μg g−1, respectively. The accuracy was evaluated through recovery tests performed with different species of Hg and CRM analysis, obtaining excellent recoveries. The values of Hg were below the LOD(m) for xanthan gum samples A and B. However, the other samples showed concentrations in the range of 0.027–0.325 μg g−1. The method proves suitable for the quantification of Hg, which is important due to the wide applicability of xanthan gum.

In the present study, the microwave induced plasma optical emission spectrometry (MIP OES) and laser-induced breakdown spectroscopy (LIBS) complementary techniques are used to determine and locate metals in ceramic tableware samples. For quantitative analysis by MIP OES, a new method for sample treatment is proposed, preparing the samples using ultrasonic decomposition aided by an acid mixture containing HNO3 and HF. The highest average concentrations were found in the group of Brazilian samples for most of the analytes. The accuracy of the quantitative method was assessed by comparing the results with two methods described in the literature. No significant differences were detected. Aiming at qualitative analysis and analyte locating by LIBS, a sample fragment was already sufficient for the analysis, being possible to observe that Al, Ba, Ca, Fe, K, Li, Mg, Na and Ti are present in the ceramic mass and decorated surface, while Cd, Co, Cr, Cu, Mn, Pb and Zn are found only on the sample surface. Besides, according to LIBS results, it would be essential to pay attention to pigmentation, which contains most of the potentially toxic elements, at locations in direct contact with food to minimize the risk of leaching and avoid human contamination. This study shows that MIP OES and LIBS can be used complementarily to improve the analytical information used to control the ceramic tableware quality and safety. The conclusions of this work can be extended to several other types of samples where both the average contents and the location of the elements are relevant.

This study presents information about the total concentration and bioaccessible fraction of barium (Ba), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), mercury (Hg), potassium (K), lithium (Li), magnesium (Mg), manganese (Mn), molybdenum (Mo), lead (Pb) and zinc (Zn) in different cultivars of tomato (Gaucho, Paulista, Italiano and Cherry) and their derivatives (sauce and tomato extract). The determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES). The bioaccessible fraction of the elements was evaluated through in vitro digestion process and the concentrations varied between 25 and 100 % ​for Cu, Fe, Mn and Zn, depending on the type of tomato sample and its derivatives. The total concentrations for all the elements studied were below the recommendation of dietary guidelines. For Ba, only the Italiano sample presented 22 % of bioaccessibility. For Pb, the highest percentage of bioaccessible fraction was found in sauces and tomato extracts. The elements Cd, Hg, Li and Mo presented concentrations lower than the limit of detection for the bioaccessibility method.

The world's declining plant biodiversity depends on the efficacy of many policy tools, including Environmental Impact Assessment (EIA). While scholars have long been trying to understand how biodiversity information affects EIA decision-making, very few studies have addressed the specific challenges associated with threatened plant species. Based on content analysis of 83 EIA processes that proposed vegetation removals in the southeastern Brazilian state of Minas Gerais, this study evaluated the extent to which threatened plant species were considered in decision-making. The study found that the developers of 31 projects (37% of the 83 analyzed EIA projects) disclosed the occurrence of threatened plant species in the potentially affected areas. The detailed content analysis of their respective Environmental Impact Statement (EIS) review reports revealed that the majority of the identified impacts and respective compensation programs targeted tree habits, and under a variety of rationales. Developers' proposed compensation rates of impacted tree species varied from 1:1 to 50:1. The reviewing process reported issues related mostly to the baseline conditions. Overall, the study found that EIA, in Minas Gerais state, has been functioning mainly as a diagnostic and compensation tool for the removal of tree species. The study calls for improvements in existing legislation and the development of technical guidance and capacity-building programs for EIA stakeholders.

We examined the female reproductive system of the yellowline arrow crab Stenorhynchus seticornis by means of histological and histochemical techniques. Mature specimens obtained in the field were kept in the laboratory for mating experiments. After 24 h, newly mated females were dissected, and their reproductive trait routinely processed for embedding in historesin. The specimens examined each possessed a pair of kidney-shaped seminal receptacles (SR), and these we classified as ventral type, based on the location of the oviduct opening. The mesodermal dorsal region (DR) of SR consisted of a stratified epithelium with scaly cells, while the ectodermal ventral region (VR) was composed of a simple epithelium covered by a cuticle. The oviduct opened at the transition region (TR) between DR and VR and had no velum. The simple epithelium of TR had more folds on the face of the oviduct opening. The vagina exhibited the same features as the TR epithelium and was contiguous to VR, anchored by muscles. In the lumen, from one to three strata of sperm packets were observed, the dorsal one containing free sperm, and the most ventral stratum, spermatophores. An acidophilic glycoprotein layer enclosed the strata. Spermatophores in the ventral stratum were enclosed in a voluminous secretion, composed by acid polysaccharides most likely from the last male mated. The ventral-type receptacle, stratified sperm packets, and polyandry, usually observed in females of Majoidea, suggest the occurrence of sperm competition in S. seticornis, favoring the sperm of the last male mated, as its sperm mass is located near the opening of the female oviduct.

This study presents a comparative evaluation of three different methods for sample preparation in rice for As, Cd, Pb, and Se determination by graphite furnace atomic absorption spectrometry (GF AAS). Raw and cooked white rice, parboiled rice, and brown rice samples were studied with the following procedures: i) HNO3 decomposition in open system with cold finger, ii) HNO3 decomposition in ultrasonic bath, and iii) alkali solubilization with TMAH. The sample preparation using reflux system was optimized and the best conditions were: 750 mg of sample, 10 mL of HNO3, 120 °C (heating), and 90 min in the digester block. In rice samples, medium concentrations of 12.0 ± 4.0 and 177.0 ± 64.0 ng g− 1 for Cd and Pb were found, respectively, while for As and Se, the concentrations were below the limit of detection of the studied methods. After cooking, samples presented a maximum decrease of 61% in Cd concentration. The method validations were assured by analysis of certified reference material (NIST 1568a), and results were in accordance with the certified values. The recovery test was carried out and results ranged between 80 and 115% for all analytes in the rice samples, before and after cooking. All evaluated procedures presented accurate and precise results; however, the decomposition with reflux system proved to be more effective, simple and secure. Such characteristics are necessary for the application in routine analysis with medium detection limits of 77.2; 1.0; 35.5 and 192.1 ng g− 1 for As, Cd, Pb and Se, respectively.

Omnidirectional absorption is important to non-tracking systems designed for the harvesting of solar energy. Presently, we examine both experimentally and numerically the broadband absorption under oblique illumination driven by deep sidewall subwavelength structures (DSSS) in silicon nanopillar arrays (DSSS arrays). Specifically, we target DSSS geometries that are a built-in side effect of the top-down cyclic Bosch dry etch process employed to realize high aspect ratio silicon nanopillar (NP) arrays. We numerically compare the DSSS array with an optically-optimized straight-sidewall nanopillar array (SSNP array) under oblique illumination. We show how the presence of DSSS generates a higher absorptivity particularly for the spectral range >600 nm, induces the formation of absorptivity peaks at the near-infrared spectral range, and overall provides an enhanced omnidirectional broadband absorption. We experimentally show that the specular reflectivity and the total reflectivity of silicon DSSS arrays that were fabricated using a top-down Bosch dry etch process is significantly lower compared with that of the corresponding SSNP arrays. Specifically, we show a decrement in the broadband specular reflection of up to 30% for certain angles of illumination, and about 13% decrement in the total reflectivity.

Light trapping and the broadband absorption of the solar radiation are significant to a plethora of absorption-based photonic devices. Specifically, efficient broadband absorption was recently demonstrated with arrays of subwavelength structures. The current study examines both numerically and experimentally light trapping driven by deep sidewall subwavelength structures (DSSS) in silicon nanopillar (NP) arrays (DSSS arrays). Particularly, the focus is on DSSS geometries that are an inherent outcome of the top-down dry etch approach used in arrays of high aspect ratio NPs due to the periodical operationality of the Bosch dry etch method. ~10% enhancement in the broadband absorption of DSSS arrays compared with NP arrays is demonstrated numerically, as well as the generation of near-IR absorptivity peaks of ~25% for DSSS arrays. Importantly, it is shown that the introduction of DSSS systematically blue-shifts the absorptivity peaks of the NP arrays and in this manner a deterministic light trapping is possible. Finally, decrements of ~40% in direct reflectivity and ~7% in diffused reflectivity in DSSS arrays realized on silicon wafers is demonstrated experimentally.

This work presents the development of an analytical method for sample preparation aiming at the K determination in silicate rocks (basalt, monzogranite and shale fines) following ultrasound dissolution and analysis by F AES. Sample preparation method was optimized by using fractional factorial designs. The following optimal conditions were obtained for each silicate rock: 0.1 g of sample mass for any of the three samples, and volumes of HNO3, HCl and HF, respectively, of 2.5, 0.8 and 2.5 mL for basalt; 3.5, 0.8 and 2.5 mL for monzogranite, and 2.5, 1.0 and 2.0 mL for shale fines. Sample dissolution was achieved by using the ultrasound bath at room temperature (25 °C) for 1 hour. The accuracy was evaluated through the analysis of two certified reference materials, for which there was no statistical difference between the certified and the found K concentration values (95% confidence level). The K concentrations determined were: 1.45 ± 0.01 for basalt; 4.19 ± 0.03 for monzogranite and 1.60 ± 0.02 for shale fines. The developed method presented accurate and reliable results for K amounts in silicate rocks and is simple and safe, which are important features for the implementation of a methodology as a routine analysis.

Silicon nanopillar (NP) arrays are known to exhibit efficient light trapping and broadband absorption of solar radiation. In this study, we consider the effect of deep subwavelength sidewall scalloping (DSSS) on the broadband absorption of the arrays. Practically, the formation of DSSS is a side effect of top-down dry etching of NP arrays of several microns height. We use finite-difference time-domain electromagnetic calculations to show that the presence of DSSS can result in efficient excitation of optical modes in both the arrays and the underlying substrates. We demonstrate a broadband absorption enhancement of >10% in a DSSS-NP array with an underlying substrate. Finally, we use device calculations to examine the effect of DSSS on the electrical performance of a photovoltaic cell, as the main concern is the degradation of the open-circuit voltage due to surface recombination (DSSS results in higher surface-to-volume ratio). We show that the effect of DSSS on open-circuit voltage is negligible. Finally, deep-subwavelength sidewall features offer a new, interesting photon management strategy towards absorption enhancement.

Our aim was to describe the reproductive system of males and the formation of sperm packages in the seminal receptacle (SR) of recently mated females of the arrow crab Stenorhynchus seticornis. The male reproductive system was analyzed, and was described using light microscopy and histological and histochemical methods. The first pair of gonopods was described by means of scanning electron microscopy. Additionally, the dehiscence of spermatophores was tested using samples obtained from the vas deferens of males and from the seminal receptacle of recently mated females. Testes were tubular type, and each vas deferens consisted of three regions: the anterior vas deferens (AVD), including a proximal portion that was filled with free spermatozoa and a distal portion contained developing spermatophores; the median vas deferens (MVD) that contained completely formed spermatophores; and the posterior vas deferens (PVD), which contained only granular secretions. The accessory gland, which was filled with secretions, was located in the transition region between the MVD and the PVD. The spermatophores from the MVD were of different sizes, and none of them showed dehiscence in seawater, whereas those spermatophores in contact with the seminal receptacle were immediately broken. The ultrastructure of the gonopods revealed the presence of denticles at the distal portion, which contribute to the mechanical rupture of the spermatophore wall during the transfer of sperm. The contents of the PVD and accessory gland of males are transferred together with the spermatophores, and are responsible for the secretions observed among the sperm packets in the SR of the female. We suggest that these secretions formed the layers found in the SR of recently mated females, and may play a role in sperm competition in arrow crabs. Fil: Antunes, Mariana. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Zara, Fernando J.. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil Fil: Lopez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; Argentina Fil: Negreiros Fransozo, María Lucía. Universidade Estadual Paulista Julio de Mesquita Filho; Brasil

Made available in DSpace on 2019-10-04T12:33:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-12-03. Added 1 bitstream(s) on 2019-10-09T18:33:48Z : No. of bitstreams: 1 S0104-64972018000100222.pdf: 2176102 bytes, checksum: 7d0bea2e2bcd6039bf8379c663354084 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) We determined the infestation rate of Probopyrus sp. in populations of Palaemon pandaliformis (Stimpson, 1871) and P. northropi (Rankin, 1898) in the Ubatumirim River, localized in a mangrove ecosystem on Ubatumirim Beach, northern coast of the state of Sao Paulo, Brazil. Samplings were carried out monthly from April 2003 to March 2004. Monthly prevalence varied from 0 to 4.94 % for P. pandahformis, and from 0 to 4.54 % for P. northropi. This is the first record of Probopyrus sp. infesting the studied species in this region. Species of Probopyrus (Giard and Bonnier, 1888) seem to have a high plasticity with regard to palaemonid hosts, as they can be parasites of shrimps in both Palaemon (Fabricius, 1798) and Macrobrachium (Spence Bate, 1868). The linear relationships between the parasite and host sizes suggest that the parasite infests both hosts early in their development. We concluded that the infestation of Probopyrus sp. has little impact on Palaemon populations, mostly due to the low prevalence of infestation. Univ Fed Piaui UFPI, Dept Biol, Ctr Ciencias Nat, Campus Minist Petronio Portella, Teresina, Piaui, Brazil Univ Estadual Paulista, UNESP, Grp Estudos Biol Ecol & Cult Crustaceos NEBECC, Dept Zool,Inst Biociencias, Botucatu, SP, Brazil Univ Paulista UNIP, Curso Ciencias Biol, Bauru, SP, Brazil Univ Sao Paulo, Dept Zool, Inst Biociencias, Sao Paulo, SP, Brazil Univ Estadual Paulista, UNESP, Grp Estudos Biol Ecol & Cult Crustaceos NEBECC, Dept Zool,Inst Biociencias, Botucatu, SP, Brazil FAPESP: 98/3234-6

In this paper, a comparative study between three acid decomposition procedures of milk powder samples for the determination of Ca, Cu, Fe, K, and Na by optical emission spectrometry with inductively coupled plasma is presented. Utilizing a reflux system, it was possible to increase the temperature of the digester block above the boiling point of the reaction medium, avoiding the loss of analyte and the excessive evaporation of the acids during the heating. Conditions of acidity (10 mL HNO3/H2SO4), temperature (350 °C), and decomposition time (4 h) were defined by evaluation of residual carbon content. Acid digestion in an open system with a cold finger was compared with a conventional open system (4 h ate 120 °C), as well as with microwave digestion (heating ramp to 180 °C by the time 45 min), for four commercial samples of milk powder. For the three sample preparation procedures, the values of the analyte concentrations in all analyzed samples were similar. The accuracy of the acid digestion procedures for Ca, Cu, Fe, K, and Na was assessed by the analysis of a certified reference material of milk (infant formula), and good agreement between the certified values and the measured value was obtained. The limits of quantification for the acid digestion with reflux system for Ca, Cu, Fe, K, and Na, in milligram per kilogram, were 7.48, 0.31, 1.0, 8.20, and 25.81, respectively, and for the microwave digestion were 14.0, 0.57, 1.78, 14.65, and 46.08, respectively. The decomposition procedure using a cold finger in an open system is effective, presenting the lowest residual carbon content (6 %), good accuracy, and relative standard deviation lower than 5 %, and appears to be a suitable procedure for sample preparation for routine analysis.

Resumo Neste trabalho, é descrito o desenvolvimento de um método analítico para análise de amostras de cervejas por técnicas de espectrometria. As amostras foram preparadas por decomposição em meio ácido, em um sistema de refluxo, e as determinações foram realizadas por F AAS (Fe, Mg e Zn), F AES (Na) e MIP OES (Ca, Fe, K, Mg, Mn, Na, Ni e Zn). As melhores condições para a decomposição da amostra foram obtidas através de estudo com delineamento composto central rotacional: volume de 10,0 mL de cerveja desgaseificada, adição de 5,0 mL de HNO3 e 2,0 mL H2O2, seguida por uma etapa de aquecimento em bloco digestor a 160 °C, por 93 min. Os limites de quantificação do método foram ≤ 0,100 mg L-1 para todos os elementos investigados, independentemente da técnica analítica utilizada, ficando abaixo, por exemplo, dos valores estipulados para Zn e Ni, pela Agência Nacional de Vigilância Sanitária do Brasil. Os estudos comparativos entre as diferentes técnicas avaliadas mostraram, pelo teste T com nível de 90% de confiança, que não há diferença significativa para as determinações de Fe, Mg, Na e Zn nas amostras de cerveja. O método de preparo da amostra proposto mostrou ser simples, rápido, de baixo custo e confiável, para análise de cervejas nas diferentes técnicas de espectrometria atômica. Abstract This study describes the development of an analytical method for the analysis of beer samples by atomic spectrometric techniques. The samples were prepared by acid decomposition using a reflux system, and the determinations carried out by F AAS (Fe, Mg and Zn), F AES (Na) and MIP OES (Ca, Fe, K, Mg, Mn, Na, Ni and Zn). The best conditions for sample decomposition were obtained by way of studies using a central rotational compound design: 10.0 mL of degassed beer followed by the addition of 5.0 mL of HNO3 and 2.0 mL H2O2 and a heating step in the digester block at 160 °C for 93 min. The quantification limits of the method were ≤ 0.100 mg L-1 for all the analytes investigated, regardless of the analytical technique used, values below those established by the Brazilian Health Surveillance Agency for Zn and Ni, for example. The comparative study of the different techniques showed that, according to the t-test at a 90% level of confidence, there was no significant difference for the determinations of Fe, Mg, Na and Zn in the beer samples. The sample preparation method was shown to be simple, fast, low-cost and reliable for the analysis of beers by the different atomic spectrometry techniques.

Fan-Out Wafer Level Packaging (FOWLP) has recently seen a tremendous growth in a broad span of application in telecommunications, automotive and other markets. Its versatility allows its continuous development to accommodate more and more types of components. In light of expanding the technology to include new family of sensors such as MEMS/NEMS, Bio-chips with Microfluidics, magneto-resistive devices and Micro-batteries, the upper limit temperature of FOWLP processing has to be challenged. FOWLP, namely the WLFO technology of NANIUM, based on Infineon/ Intel eWLB technology, is a packaging technology based on wafer reconstitution and RDL processes. The “LTC - low temperature cure” dielectrics used today, are cured at > 200oC, while solder ball soldering peaks ~260oC. Despite being considered low temperature, this limit is still not compatible and considered high to a wide range of the new family of sensors targeted to integrate in WLFO. In this work we describe the strategy to lower overall process temperature to

The acid decomposition method was applied for the sample preparation of processed fruit juice. The decomposition of 15mL of juice sample using HNO3 and H2O2 was performed in a digester block with reflux system and heated at 200°C for 150min. The limits of detection were 0.03; 0.24; 0.8; 0.008; 0.026 and 0.056mgL-1 for Cr, Cu, K, Mg, Na and Zn, respectively and for Pb was 0.99μgL-1. The accuracy was evaluated by spiked experiments (80 to 119%). Four processed fruit juice samples commercialized in Brazil (strawberry, mango, peach, and orange) were analyzed and indicated the absence of Cr, Zn and Cu in the samples, except for Cu in strawberry juice. Pb was found in the mango juice sample (17.8±0.9μgL-1) and the concentration is below the maximum values recommended by Brazilian legislation for juices of citric fruits (0.3mgkg-1).

The objective of this study was to evaluate the concentration of Cu, Zn, Cr and Pb in different species of fish collected in the estuarine and limnic regions of the São Gonçalo channel, located in the Patos-Mirim lagoon complex in the coastal plain of Rio Grande do Sul State (Southern Brazil) during 2013 (autumn, winter and spring) and 2014 (summer). Fish samples were decomposed in a digester block with a reflux system under conditions optimized using a central composite design as it follows: 250 mg of fish sample, 5 mL HNO3, 2 mL H2O2 during 2 h at 150 °C. The concentrations obtained ranged from 6.7 to 12.0 mg kg -1 for Cu; 1.8 to 23.6 mg kg -1 for Zn; 37 to 487 µg kg -1 for Pb; and 40 to 1268 µg kg -1 for Cr. The highest concentrations of Cu, Zn and Pb, were observed in fishes collected at locations in the estuarine region and Cr showed high levels, especially in the limnic region. The samples of the species Loricariichthys anus (viola) showed the highest concentrations of all analytes investigated.

In this work, the photochemical vapor generation (PVG) coupled with atomic absorption spectrometry and a pre-concentration step with an Au column was used for the determination of Hg in biological samples and ethanol fuel. PVG with pre-concentration showed an up to 250-fold higher sensitivity compared to the approach without pre-concentration. The accuracy of analysis of biological samples was evaluated using certified reference materials (fish tissues), while for ethanol fuel samples, recovery tests were employed (91%). Analytical curves were linear (R > 0.99) in the studied range of 2.5 to 10 µg L-1 for conventional PVG and 0.2 to 0.5 µg L-1 for PVG with the pre-concentration step. For the last, the limits of detection reached for biological samples and ethanol fuel were 0.02 and 0.01 µg L-1, respectively. The systems presented are simple, sensitive and safe for the control of low Hg concentrations in different samples. However, only the system using pre-concentration with an Au column was capable of obtaining the reproduced signals of Hg in low concentrations of the order of 0.2 µg L-1.

This paper presents a study involving the development of a new mini polytetrafluoroethylene (PTFE) vessel project for biological sample preparation in micro scale in closed system with microwave radiation for subsequent determination of Cd, K, Mg and Na by atomic spectrometry techniques. All experiments were carried out in micro quantities of samples (up to 20 mg) and reagents (300 µL of HNO3) for 5 min at 350 W. Certified reference materials of biological samples (bovine muscle and liver) were used to evaluate the accuracy of the proposed system and the results obtained were in agreement with the certified value at 95% of confidence (t -test). Relative standard deviations (RSD) were lower than 8.0% for all elements. The proposed method is not only easy and fast, but it is also based on the use of an inexpensive system for sample digestion.

Made available in DSpace on 2018-12-11T17:20:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-01 Knowledge of the critical points in larval stages is essential to evaluate the physiological state of the larvae in their natural environment. This study investigated the nutritional vulnerability index (NVI) of the first (ZI) and second (ZII) zoeal stages of Stenorhynchus seticornis. Zoeae were assigned to two experiments: (1) point of no return (PNR), consisting of treatments with increasing days of starvation and subsequent days of feeding; and (2) point of reserve saturation (PRS), consisting of treatments with increasing days of feeding and subsequent days of starvation. There were two control groups: continuous starvation (CS) and continuous feeding (CF). Mortality was used to estimate the time when 50% of initially starved larvae (PNR 50) lost the ability to moult to the next stage and when 50% of initially fed larvae (PRS 50) were capable of moulting to the next stage. The mean (±s.d.) development time of ZI and ZII under CF was 4.4 ± 1.2 and 5.1 ± 1.8 days respectively. Mortality in the CF groups was 30 and 52% for ZI and ZII respectively. For ZI, PNR 50 and PRS 50 were 1.0 ± 0.0 and 2.1 ± 1.0 days respectively. The estimated NVI for ZI was 2.2, which indicates that S. seticornis depends on exogenous food and is considered planktotrophic during the first larval stage. Carcinology Laboratory Universidade Federal de Sergipe (UFS), Avenida Marechal Rondon, s/n Group of Studies on Crustacean Biology Ecology and Culture (NEBECC) Departamento de Zoologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Universidad de Buenos Aires Consejo Nacional de Investigaciones Científicas y Técnicas Instituto de Biodiversidad y Biología Experimental y Aplicada Facultad de Ciencias Exactas y Naturales Depto. de Biodiversidad y Biol. Exp. Biol. de la Reprod. y El Crecimiento de Crustaceos Decapodos Departamento de Zoologia Universidade Estadual Paulista (UNESP) Distrito de Rubião Júnior Group of Studies on Crustacean Biology Ecology and Culture (NEBECC) Departamento de Zoologia Instituto de Biociências Universidade Estadual Paulista (UNESP) Departamento de Zoologia Universidade Estadual Paulista (UNESP) Distrito de Rubião Júnior

This paper describes a sample preparation method for domestic ceramics, based on the acid decomposition assisted by ultrasound for further determination of Cu, Fe, Mg and Zn by Flame Atomic Absorption Spectrometry technique. The main optimized conditions were: particle size (25 µm); sample mass (25 mg) and the acid volume (0.5 mL of HNO3 and 0.5 mL of HF). The samples were placed in an ultrasonic bath for 2 hours at 40 oC. The method was employed for eight commercial samples of domestic ceramic, which showed different concentrations for all analytes investigated, showing the existing variety of raw materials. The method showed good accuracy and precision, attested by the addition and recovery test, with values of 87 to 112% for all analytes and relative standard deviation lower than 3.0%.