957 resultados para non-destructive test


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Terahertz (THz) radiation is being developed as a tool for the analysis of cultural heritage, and due to recent advances in technology is now available commercially in systems which can be deployed for field analysis. The radiation is capable of penetrating up to one centimetre of wall plaster and is delivered in ultrafast pulses which are reflected from layers within this region. The technique is non-contact, non-invasive and non-destructive. While sub-surface radar is able to penetrate over a metre of wall plaster, producing details of internal structures, infrared and ultraviolet techniques produce information about the surface layers of wall plaster. THz radiation is able to provide information about the interim region of up to approximately one centimetre into the wall surface. Data from Chartres Cathedral, France, Riga Dome Cathedral, Latvia, and Chartreuse du Val de Bénédiction, France is presented each with different research questions. The presence of sub-surface paint layers was expected from documentary evidence, dating to the 13th Century, at Chartres Cathedral. In contrast, at the Riga Dome Cathedral surface painting had been obscured as recently as 1941 during the Russian occupation of Latvia using white lead-based paint. In the 13th Century, wall paintings at the Chapel of the Frescos, Chartreuse du Val de Benediction in Villeneuve les Avignon were constructed using sinopia under-painting on plaster covering uneven stonework.. This paper compares and contrasts the ability of THz radiation to provide information about sub-surface features in churches and Cathedrals across Europe by analysing depth based profiles gained from the reflected signal. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

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The effects of iron ions on dielectric properties of lithium sodium phosphate glasses were studied by non-usual, fast and non-destructive microwave techniques. The dielectric constant (epsilon`). insertion loss (L) and microwave absorption spectra (microwave response) of the selected glass system xFe(2)O(3)center dot(1 - x)(50P(2)O5 center dot 25Li(2)O center dot 25Na(2)O), being x = 0, 3, 6, ....,15 expressed in mol.%, were investigated. The dielectric constant of the samples was investigated at 9.00 GHz using the shorted-line method (SLM) giving the minimum value of epsilon` = 2.10 +/- 0.02 at room temperature, and increasing further with x, following a given law. It was observed a gradual increasing slope Of E in the temperature range of 25 <= t <= 330 degrees C, at the frequency of 9.00 GHz. Insertion loss (measured at 9.00 GHz) and measurements of microwave energy attenuation, at frequencies ranging from 8.00 to 12.00 GHz were also studied as a function of iron content in the glass samples. (C) 2009 Elsevier Ltd. All rights reserved.

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To date, limited numbers of dental calculus samples have been analyzed by researchers in diverse parts of the world. The combined analyses of these have provided some general guidelines for the analysis of calculus that is non-destructive to archaeological teeth. There is still a need for a quantitative study of large numbers of calculus samples to establish protocols, assess the level of contamination, evaluate the quantity of microfossils in dental calculus, and to compare analysis results with the literature concerning the biology of calculus formation. We analyzed dental calculus from 53 teeth from four Brazilian sambaquis. Sambaquis are the shell-mounds that were established prehistorically along the Brazilian coast. The analysis of sambaqui dental calculi shows that there are relatively high concentrations of microfossils (phytoliths and starch), mineral fragments, and charcoal in dental calculus. Mineral fragments and charcoal are possibly contaminants. The largest dental calculi have the lowest concentrations of microfossils. Biologically, this is explained by individual variation in calculus formation between people. Importantly, starch is ubiquitous in dental calculus. The starch and phytoliths show that certainly Dioscorea (yam) and Araucaria angustifolia (Parana pine) were eaten by sambaqui people. Araceae (arum family), Ipomoea batatas (sweet potato) and Zea mays (maize) were probably in their diet. (C) 2009 Elsevier Ltd. All rights reserved.

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sigma(S) is responsible for the transcriptional regulation of genes related to protection against stresses and bacterial survival and it accumulates in the cell under conditions of stress, such as nutrient limitation. An increase in the levels of sigma(S) causes a reduction in the expression of genes that are transcribed by RNA polymerase associated with the principal sigma factor, sigma(70). phoA, that encodes alkaline phosphatase (AP) is expressed under phosphate shortage conditions, and is also repressed by sigma(S). Here we show that in a Pi-limited chemostat, accumulation of rpoS mutations is proportional to the intrinsic level of sigma(S) in the cells. Acquisition of mutations in rpoS relieves repression of the PHO genes. We also devised a non-destructive method based on the rpoS effect on AP that differentiates between rpo(S+) and rpoS mutants, as well as between high and low-sigma(S) producers. Using this method, we provide evidence that sigma(S) contributes to the repression of AP under conditions of Pi excess and that AP variation among different strains is at least partly due to intrinsic variation in sigma(S) levels. Consequently, a simple and non-destructive AP assay can be employed to differentiate between strains expressing different levels of sigma(S) on agar plates.

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A non-destructive sorting method to separate single-walled carbon nanotubes (SWNTs) by diameter was recently proposed. By this method, SWNTs are suspended in water by surfactant encapsulation and the separation is carried out by ultracentrifugation in a density gradient. SWNTs of different diameters are distributed according to their densities along the centrifuge tube. A mixture of two anionic surfactants, namely sodium dodecylsulfate (SDS) and sodium cholate (SC), presented the best performance in discriminating nanotubes by diameter. Unexpectedly, small diameter nanotubes are found at the low density part of the centrifuge tube. We present molecular dynamics studies of the water-surfactant-SWNT system to investigate the role of surfactants in the sorting process. We found that surfactants can actually be attracted towards the interior of the nanotube cage, depending on the relationship between the surfactant radius of gyration and the nanotube diameter. The dynamics at room temperature showed that, as the amphiphile moves to the hollow cage, water molecules are dragged together, thereby promoting the nanotube filling. The resulting densities of filled SWNT are in agreement with measured densities.

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A robust, direct, rapid and non-destructive X-ray diffraction crystallography method to detect the polyprenylated benzophenones 7-epi-clusianone (1) and guttiferone A (2) in extracts from Garcinia brasiliensis is presented. Powder samples of benzophenones 1 and 2, dried hexane extracts from G. brasiliensis seeds and fruit`s pericarp, and the dried ethanolic extract from G. brasiliensis seeds were unambiguously characterized by powder X-ray diffractometry. The calculated X-ray diffraction peaks from crystal structures of analytes 1 and 2, previously determined by single-crystal X-ray diffraction technique, were overlaid to those of the experimental powder diffractograms, providing a practical identification of these compounds in the analyzed material and confirming the pure contents of the powder samples. Using the X-ray diffraction crystallography method, the studied polyprenylated benzophenones were selectively and simultaneously detected in the extracts which were mounted directly on sample holder. In addition, reference materials of the analytes were not required for analyses since the crystal structures of the compounds are known. High performance liquid chromatography analyses also were comparatively carried out to quantify the analytes in the same plant extracts showing to be in agreement with X-ray diffraction crystallography method. (C) 2010 Elsevier B.V. All rights reserved.

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Tourism as an example of alternative for sustainable development in the Lençóis Maranhenses. The objective of this work is to analyze the prospects for sustainable development in tourism in the aforementioned region. An attempt is made to evaluate the five dimensions of sustainable - ecological, economic, social, space and cultural. The base for discussion is the information gathered from the people who actually live in the region. A type of the case study was built up. The research involved speaking with the people about the viability of tourism projects, not only with an eye on economic success, job creation and income for the region. There was also an attempt to tackle the issue of social and environment impact. Data was collected through verbal contact. A variety of people were interviewed, locals, businessmen, authorities, civil representatives and they spoke about the advantages and disadvantages of tourism as the saw it and as it affected them. Their answers and comments constitute the knowledge gleaned. The development of possible new strategies is the result of this work. Strategies that should be investigated by the local government/public administration. One such strategy would involve strengthening ties whit society and hoping that the improved dialogue would encourage sustainability. Another would mean improving interdepartmental contact to streamline the performance of public bodies so that development can be better planned and non-destructive.

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In an environment of constant change, technological developments, market competition and more informed consumers, the search for a lasting relationship through the conquest of loyalty has become the objective of companies. However, several authors suggest that this loyalty can be affected by negative comments available on the internet. Therefore, this dissertation has as objective to examine if the complaints are available on the internet impact the loyalty to a brand of mobile phone. The research used as the basis the Expanded NCSB model suggest by Johnson et al. (2001), studying five prominent drives of loyalty: image/brand reputation, affective commitment, calculative commitment, perceived value and trust, beyond the satisfaction construct as moderator variable. The research method adopted was the experimental design which included 285 undergraduate students, with the trial which included 285 undergraduate students, with the field study of the mobile industry, specifically, the brands of cell phones. The research approach was quantitative and methods were descriptive statistics, factor analysis, cluster analysis, linear regression and non-parametric test of Wilcoxon for data analysis. Of the 16 hypothesis stemmed from the research model proposed, 12 were confirmed. The results showed that the complaint available on the internet, here represented by the available on the site Reclame Aqui, may impact consumer perceptions about brand loyalty, as well as its antecedents, being that these complaints can affect all the consumers, regardless of historical satisfaction with the brand. It also noted the positive relationship between the independent variables trust, image/brand reputation, perceived value, affective commitment and calculative commitment and the dependent variable - loyalty, even when considering the data obtained after exposure to the complaint. However, no unanimous conclusion that the relationship between these variables was strongest in the group with satisfactory experience. At the first moment of the research, the trust was the most important variable for the formation of loyalty. However, after exposure to treatment, the image/brand reputation, was more relevant. Contributions of the study, limitations and recommendations for future researches are approached in the present investigation

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Polymer matrix composites offer advantages for many applications due their combination of properties, which includes low density, high specific strength and modulus of elasticity and corrosion resistance. However, the application of non-destructive techniques using magnetic sensors for the evaluation these materials is not possible since the materials are non-magnetizable. Ferrites are materials with excellent magnetic properties, chemical stability and corrosion resistance. Due to these properties, these materials are promising for the development of polymer composites with magnetic properties. In this work, glass fiber / epoxy circular plates were produced with 10 wt% of cobalt or barium ferrite particles. The cobalt ferrite was synthesized by the Pechini method. The commercial barium ferrite was subjected to a milling process to study the effect of particle size on the magnetic properties of the material. The characterization of the ferrites was carried out by x-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM) and vibrating sample magnetometry (VSM). Circular notches of 1, 5 and 10 mm diameter were introduced in the composite plates using a drill bit for the non-destructive evaluation by the technique of magnetic flux leakage (MFL). The results indicated that the magnetic signals measured in plates with barium ferrite without milling and cobalt ferrite showed good correlation with the presence of notches. The milling process for 12 h and 20 h did not contribute to improve the identification of smaller size notches (1 mm). However, the smaller particle size produced smoother magnetic curves, with fewer discontinuities and improved signal-to-noise ratio. In summary, the results suggest that the proposed approach has great potential for the detection of damage in polymer composites structures

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Fibromyalgia (FM) is a chronic rheumatic syndrome characterized by diffuse muscle-skeletal pain, and aerobic exercises represent a fundamental portion in therapeutic approach. Objective of this study was to evaluate the effectiveness of aerobic exercises accomplished in the water of the sea (thalassotherapy) for women with FM and to compare with exercises accomplished in the swimming pool, involving a multidisciplinary team, composed by rheumatologists, physical therapists, students of physical therapy and students of physical education. Forty six (46) women with age between 18 and 60 years with FM were randomized in 2 groups: a swimming pool group (23 patients) and a sea group (23 patients). 80th groups trained a week with the same program of aerobic conditioning 3 times (60 minutes each) for 12 weeks. Ali the patients were evaluated, before and immediately after treatment, with Visual Analogical Scale (VAS) for pain and fatigue, number of tending points, Fibromyalgia Impact Ouestionnaire (FIO), Short Form 36 Health Survey (SF-36), Pittsburgh Sleep Ouality Index (PSOI) and Beck Oepression Inventory (BOI). For statistical analysis, it was used paired-t test for analysis intra-group and non-paired test for inter-groups analysis, significance levei of p <0,05. Four patients, of each group, didn't complete the training programo Groups were homogeneous and they were compared in initial evaluation, except for BOI (p <0,05). Both groups presented statistically significant improvement for ali appraised parameters in the post-treatment compared with initial evaluation, there were reduction of intensity of pain and fatigue, number of tending points, better functional capacity (FIO), life quality (SF-36), quality of sleep (PSQI) and depression indexes (BOI). However, in comparison among the groups, group of sea (thalassotherapy) presented better results for ali parameters, however with statistically significant difference just only for depression indexes (BOI). At the end, it was observed that accomplishment of aerobic exercises in sea water or swimming pool was effective as part of treatment for patients with FM. However, exercise programs with thalassotherapy seems to bring more benefits, mainly related to emotional aspects, could be a therapeutic option of low cost for patients with FM in our area

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The application of ergonomics in product design is essential to its accessibility and usability. The development of manual devices should be based on ergonomic principles. Effort perception analysis is an essential approach to understand the physical and subjective aspects of the interface. The objective of the present study was to analyze the effort perception during a simulated task with different door handles by Portuguese subjects of both genders and different ages. This transversal study agreed with ethical aspects. 180 subjects of both genders pertaining to three age groups have participated. Five door handles with different shapes were evaluated. A subjective numeric rating scale of 5 levels was used to evaluate the effort. For statistical analysis it was applied the Friedman non-parametric test. The results have showed no significant differences of effort perception in door handles "A" and "B"; "A" and "D"; and "D" and "C". Door handle "E" presented the lowest values of all. In general, there's an inverse relationship between the results of biomechanical studies and the effort perception of the same task activity. This shows that door handles design influence directly these two variables and can interfere in the accessibility and usability of these kinds of products.

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The first reference map of the proteome of pooled normal dog tears was created using 2-dimensional polyacrylamide gel electrophoresis and the identity of a number of the major species determined using matrix-assisted laser desorption time of flight mass spectrometry (MALDI-TOF) and peptide mass fingerprint matching on protein sequence databases. In order to understand the changes in protein expression in the tear film of dogs with cancer, tears from such animals were similarly examined. A number of differences were found between the tears of healthy dogs and the dogs with cancer. Differences were found in levels of actin and albumin and in an unidentified protein which may be analogous to human lacryglobulin. These findings suggest that it may be possible to develop tear film analysis to provide a simple non-invasive test for the diagnosis and/or management of canine cancers. (C) 2007 Elsevier Ltd. All rights reserved.

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The analysis of some aspects of development in Brazil in the past three decades reveals an improvement on a range of indicators isolated in the south east the richest region and north east the poorest region. From a database of twenty variables, the main purpose the study was to verify if there are indications of convergence or divergence in five dimensions of development between the two regions from 1990 to 2010. Aiming to identify the states more similar and different, and to verify changes in the composition of low development groups and high development in the adressed period, was used the analysis of groupings (Cluster Analysis). Additionally, to test equality of distance between states all the time, was used the non-parametric Test of Wilcoxon. This makes it possible to verify IF the distance between the states of two regions has been increasing or has been falling, showing signs of divergence or convergence. The results of Cluster s analysis suggest that there are indications of convergence inside the cluster of north east, but the distance between two regions has not changed. The results of test of Wilcoxon suggests that there have been no changes statistically significant in the distance between the states, in the two regions the standards of development became more homogenous, but the two regions will be far apart

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)