This dissertation addresses two aspects of the theory and simulation of stress-diffusion coupling in semiconductors. The first part is a study of the role of kinetics in the formation of pits in stressed thin films. The second part describes how atomic-scale calculations can be used to extract the thermodynamic and elastic properties of point-defects.<br />Recently, pit nucleation has been observed in a variety of semiconductor thin films. We present a model for pit nucleation in which the adatom concentration plays a central role in controlling the morphological development of the surface. Although pits relieve elastic energy more efficiently than islands, pit nucleation can be prevented by a high adatom concentration. Three-dimensional islands act as adatom sinks and the lower adatom density in their vicinity promotes pit nucleation. Thermodynamic considerations predict several different growth regimes in which pits may nucleate at different stages of growth depending on the growth conditions and materials system. When kinetics are taken into account, the model predicts a wide range of possible morphologies: planar films, islands alone, island nucleation followed by pit nucleation, and pits alone. The model shows good agreement with experimental observations in III-V systems given the uncertainties in quantifying experimental parameters such as the surface energy.<br />The same stresses which lead to the nucleation of surface features can have a significant effect on the stability of dopant profiles by altering diffusivities and by inducing chemical potential gradients. We perform an extensive set of empirical calculations regarding a simple model point-defect, a vacancy in the Stillinger Weber model of silicon. In the context of these calculations we devise a method to extract the strength of the elastic relaxation in the vicinity of the defect. This quantity is extracted from the leading order term which must be evaluated sufficiently far from the defect and the boundaries. It is also directly related to the formation volume, the thermodynamic quantity that couples the defect free energy to the externally applied stress. We propose that this method of extracting the formation volume is more accurate than a direct measurement of the surface relaxation for large system sizes.

Σκοπός της παρούσας διπλωματικής εργασίας είναι η μελέτη της επίδρασης της θερμικής κόπωσης στη μηχανική συμπεριφορά κοκκωδών συνθέτων υλικών πολυμερικής μήτρας ενισχυμένης με κόκκους ελαιοπυρήνα υπό μορφή σκόνης. Τα σύνθετα υλικά που κατασκευάσθηκαν μελετήθηκαν πειραματικά και τα αποτελέσματα αναλύθηκαν και προβλέφθηκαν θεωρητικά. Αρχικά πραγματοποίηθηκε η κατασκευή των συνθέτων υλικών σε διάφορες περιεκτικότητες σε κόκκους ελαιοπυρήνα. Από τον μηχανικό χαρακτηρισμό με στατικά πειράματα κάμψης τριών σημείων όλων των συνθέτων υλικών που κατασκευάστηκαν, διαπιστώθηκε η ενισχυτική ικανότητα του ελαιοπυρήνα σε μορφή σκόνης όταν αυτή χρησιμοποιείται ως υλικό ενίσχυσης για την κατασκευή συνθέτων υλικών. Ενώ, στη συνέχεια μελετήθηκε και η επίδραση της θερμικής κόπωσης στη μηχανική συμπεριφορά των συνθέτων υλικών που κατασκευάστηκαν. Τέλος, εφαρμόστηκαν δύο διαφορετικά μοντέλα πρόβλεψης του μέτρου ελαστικότητας συναρτήσει της περιεκτικότητας καθώς και της εναπομείνουσας αντοχής και δυσκαμψίας συναρτήσει των κύκλων θερμικής κόπωσης και έγινε σύγκριση των πειραματικών αποτελεσμάτων με τις αντίστοιχες προβλέψεις. Από τη σύγκριση αυτή παρατηρούμε ότι τα θεωρητικά μοντέλα που εφαρμόστηκαν που είναι το Μ.P.M (Modulus Predictive Model) και το R.P.M (Residual Properties Model) έδωσαν πολύ καλές προβλέψεις για την μεταβολή των ιδιοτήτων. Σαν γενικό συμπέρασμα από την παρούσα εργασία προκύπτει το γεγονός ότι το φθηνό και ελαφρύ υλικό του ελαιοπυρήνα μπορεί να χρησιμοποιηθεί αποτελεσματικά σαν υλικό ενίσχυσης ρητινών με πολύ καλά αποτελέσματα ενίσχυσης. / The aim of the present master thesis is to investigate the effect of thermal fatigue on the mechanical properties of particulate composites reinforced with olive pit’s powder. The composites materials that have been manufactured were investigated both; experimentally and theoretically. First, we manufactured composites reinforced with olive pits at different volume fractions of the filler particles. From the mechanical characterization of the materials investigated by means of static three-point bending experiments. It was found that the olive pits can reinforce the mechanical properties of composites materials when used as reinforced fillers. Next, the effect of thermal fatigue on the mechanical behaviour of the composites materials was investigated and theoretical predictions for their properties with and without thermal fatigue were made. More precisely, the Μ.P.M (Modulus Predictive Model) and the R.P.M (Residual Properties Model) models have been applied. A fair aggreement between experimental findings and theoretical predictions was found in all cases.

This thesis brings new information about development of five chosen snad-pits in CHKO Třeboňsko. It represents future state of this sand-pits with different rate of near ? natural restoration used during the reclamation. The results are accompanied by comparison of surface temperature of each category of land cover.

Trust is one of the attitudes that can affect the intentions and the behavior of a human using a system. Misusing a system can have safety- as well as economic consequences, this is why it is important that a user develops calibrated trust towards a system. In this report, the research question is: how much trust cross country skiers have towards a physical intelligent tutoring system (PITS)? Six biological males (age 24 to 50) roller skied on a mechanical treadmill and received feedback from the PITS on a TV-screen. Experience of using the PITS was evaluated with an instrument in a semi-structured interview. The instrument measured the participants overall perceived trust (OPT) for the system, and the participants were asked to further their thoughts about the statements. The data was transcribed, coded, and categorized in a thematic analysis. The result showed that a majority of the participants had low OPT for the PITS, and the thematic analysis showed that the minority with higher levels of OPT focused on the choice of an elite skier as the reference skier. One of the problems with the instrument was that it was developed for evaluation in long term usage, and not first time usage as in this study. The result of this report can be used for further development of the PITS and a reminder on why trust needs to be considered when creating user experiences.

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2018-02-08T15:15:15Z No. of bitstreams: 1 EduardoDuarteMarques2006.pdf: 2528290 bytes, checksum: 0f9b39f78fb8e487856383e7e30a4789 (MD5) / Made available in DSpace on 2018-02-08T15:15:15Z (GMT). No. of bitstreams: 1 EduardoDuarteMarques2006.pdf: 2528290 bytes, checksum: 0f9b39f78fb8e487856383e7e30a4789 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geoquímica, Niterói, RJ / O Distrito Areeiro de Seropédica-Itaguaí, considerado um dos maiores do Brasil, com mais de oitenta empresas de mineração, abastece aproximadamente 90% da areia para a construção civil da Região Metropolitana do Rio de Janeiro. O processo de extração de areia se dá através da retirada das camadas sedimentares superficiais da região, caracterizadas por depósitos de areia, de composição quartzo-feldspática, fazendo com que a superfície freática do Aqüífero Piranema aflore, preenchendo as cavas resultantes. Contudo, esta atividade suscita em mudanças físicas e químicas nestas águas. Quatro areais foram monitorados no período entre janeiro de 2004 e novembro de 2005 com o objetivo de caracterizar os processos hidrogeoquímicos ocorrentes nas cavas, podendo fornecer informações para uma possível transformação das cavas em “lagoas” para piscicultura ao término da atividade mineradora. Os resultados mostraram que os baixos valores de pH (3,11 – 5,2) e altas concentrações de sulfato (3 – 97,64 mg.L-1) encontrados nestas águas têm origem em reações de oxidação do material sedimentar reduzido, contendo pirita e gás sulfídrico, através da extração da areia. Valores anômalos de alumínio (> 10 mg.L-1) nas águas se devem ao baixo pH, o qual aumenta a solubilidade dos minerais silicáticos aluminosos (feldspatos e micas). Porém, os teores de alumínio nestas águas se mostram controlados pela precipitação pluviométrica, ou seja, quanto menor a precipitação em um determinado período, maior é o teor de alumínio e quanto maior a precipitação, menor o teor de alumínio. Além disso, a sílica presente nas cavas, que se apresenta na forma coloidal, pode contribuir para a redução do alumínio dissolvido através da reação entre ambos, resultando em um aluminossilicato, denominado imogolita. O ferro e manganês se apresentam, respectivamente, na forma precipitada (hidróxidos, Fe3+) e dissolvida (Mn2+). O cloreto possui concentrações constantes nas águas em estudo devido ao seu caráter conservativo e é originado por deposição atmosférica (aerossóis marinhos). O intemperismo nas cavas foi caracterizado a partir das concentrações de cálcio, magnésio, potássio, sódio e sílica. O grau de intemperismo se mostrou incipiente, onde diagramas de estabilidade mineral indicaram equilíbrio das águas com minerais primários e montmorilonitas, conseqüentemente, apresentando a bissialitização como o tipo predominante de intemperismo. A transformação das cavas de extração de areia em locais propícios à cultura de peixes deverá levar em conta a geoquímica do alumínio nestas águas, devido sua toxicidade para tais indivíduos. / Seropédica-Itaguaí Sand Mining District has an important role to the Rio de Janeiro Metropolitan Region, supplying about 90% of the sand to its civil construction. The sand extraction process is fact by the remove of the surface sedimentary layers (quartzfeldspatic composition), make water table to fill up the produced pits. However, this activity provides some chemical and physical-chemical changes in that water. Four sand pits were monitored in the period between January 2004 and November 2005, that aims to characterize the hydrogeochemical process that occurs in that water, providing information to the transformation of the pits in “ponds” for fish culture at the end of mining activities. The results show low values of pH (3,11 – 5,2) and high concentrations of sulfate (3 – 97,64 mg.L-1) in those waters and it must be given by oxidation reactions on reduced sedimentary materials with some sulfide content, caused by the sand extraction. Anomalous values for aluminum (> 10 mg.L-1) are fact by the low pH of the analyzed waters, which increase the aluminosilicate minerals solubility (feldspars and micas). However, aluminum concentrations show that are controlled by pluviometric precipitation, or be, the aluminum concentrations are bigger as much as minor the pluviosity. Besides this fact, the silica content in the extraction holes, which is in colloidal form, could contribute for the aluminum content reduction through the reaction between aluminum and silica, resulting in the formation of an aluminosilicate (imogolite). Iron and manganese are, respectively, precipitated as hydroxides (Fe3+) and dissolved form as Mn2+. Chloride has constant concentrations in those waters by its conservative characteristic and is originated by atmospheric deposition (marine aerosols). The weathering in the extraction holes was characterized by the calcium, magnesium, potassium, sodium and silica concentrations. The weathering rating is incipient, where the stability diagrams pointed out the water equilibrium with primary minerals and montmorillonite clays, consequently, presenting the bisialitization as the predominant weathering type. For the transformation of the sand extraction pits in fish culture ponds, must be considered the aluminum geochemistry because its toxicity on these individuals.

O objetivo desse estudo foi avaliar in vitro e in situ a efetividade de irradiação dos lasers Er:YAG, Nd:YAG e CO2 no aumento da resistência ácida do esmalte em regiões de sulcos e fissuras. Para o estudo in vitro foram utilizados molares humanos em fragmentos da porção oclusal de 8mmx4mm divididos em 3 grupos de acordo com o tipo de tratamento : Grupo 1 - Er:YAG; Grupo 2 - Nd:YAG; Grupo 3 - CO2 (n=15). O tratamento de superfície foi feito apenas em metade da área do fragmento, sendo que a outra metade foi considerada controle. As áreas expostas ao desafio cariogênico (14mm2) foram submetidas a ciclagens de pH. Para o testede microdureza os espécimes foram seccionados ao meio e a parede da secção é que sofreu o teste, a outra metade foi utilizada para análise em microscopia de luz polarizada para a medição da área da lesão de desmineralização e análise em MEV para verificar as alterações na morfologia do tecido dentário. As análises dos dados de microdureza (HKN) e área das lesões (mm2) foram feitas com o teste de Wilcoxon para a comparação interna de cada grupo com o seu controle e a comparação entre os grupos utilizou ANOVA para as áreas das lesões e Kruskal Wallis para a microdureza (&alpha; = 5%). Foi observada apenas diferença estatística significante para as amostras do grupo irradiado com laser CO2 entre as partes controle e experimental. Os demais grupos não apresentaram diferença estatisticamente significante com sua área controle. Na análise das medidas de lesão foram observadas diferença estatística significante para as amostras do grupo irradiado com os lasers CO2 e Nd:YAG com suas partes controles, sendo as medidas de área de lesão apresentadas pela área irradiada inferiores a área controle. Na análise em MEV o grupo irradiado com laser CO2 mostrou ausência de exposição dos prismas de esmalte e modificação de superfície na área irradiada. Para o estudo in situ foram utilizados molares humanos em fragmentos da porção oclusal de 4mmx4mm tratados com os 3 diferentes tipos de laser: Grupo 1 - controle (sem tratamento); Grupo 2 - Er:YAG; Grupo 3 - Nd:YAG; Grupo 4 - CO2 (n=15). Os espécimes foram adaptados a um dispositivo intrabucal que foi utilizado pelos voluntários durante 14 dias. Para o desafio cariogênico gotejou-se solução de sacarose 20% sobre os espécimes. Assim como no estudo in vitro, foram realizados o teste de microdureza, análise em microscópio de luz polarizada e análise em MEV. Para a análise dos dados de microdureza (HKN) foi utilizada ANOVA e teste de Fisher LSD (&alpha;= 5%). Foi observada diferença estatística significante para as amostras do grupo irradiado com laser CO2 e Nd:YAG, que apresentaram maiores valores de microdureza do que o grupo controle e não foram diferentes estatisticamente entre si. Os valores de microdureza observados em profundidade foram maiores proporcionalmente a distância da superfície, ou seja, 20&micro;m <30&micro;m <40&micro;m <50&micro;m. Na análise em microscopia de luz polarizada a análise foi feita com teste de Wilcoxon e todos os grupos apresentaram semelhança estatística. Considerando os resultados obtidos nos dois estudo pode-se concluir que os lasers CO2 e Nd:YAG foram capazes de promover aumento de resistência ácida no esmalte dental localizado nas superfície de sulcos e fissuras. / The aim of this study was to assess in vitro and in situ the lasers Er:YAG, Nd:YAG e CO2 in preventing enamel demineralization on the pits and fissures surface. For the in vitro study 45 occlusal enamel blocks were randomly divided into 3 groups in according with the treatment: G1 - Er:YAG; G2 - Nd:YAG; G3 - CO2. Treatments were made only on a half of the specimen and the remaining part was considered as a control. The samples were submitted to an in vitro pH cycles. For the microhardness test the specimens were seccioned in the middle and the seccioned wall received the test. The other halves were analyzed using polarized light microscopy for the measurement of the caries-lesion areas and morphological SEM analyses. Wilcoxon test were performed for the statistical analysis of the data obtained from the microhardness test (KHN) and caries-lesion area measurements (mm2) (&alpha;= 5%) when each groups was compared with its control. Variance analysis were performed for the difference in means of microhardness data and Kruskal Wallis test were performed for the difference in means of caries-lesion area measurements (&alpha;= 5%). For the microhardness data the G3 was statically different from its control area and the others groups presented statistical similarity among the experimental and control areas. For the caries-lesion area measurements statistical difference was observed for the groups G2 and G3 presenting smaller caries-lesion area when compared with their respective control areas. In the SEM analysis the G3 showed uniform surface without enamel-prism exposure. For the in situ study 60 occlusal enamel blocks were randomly divided into 4 groups in according with the treatment: G1 - Control (no treatment); G2 - Er:YAG; G3 - Nd:YAG; G4 - CO2 (n=15). The specimens were fixed in intra oral appliances and worn by the volunteers for 14d. Sucrose solution (20%) was applied to each specimen 6 times/d. As the in vitro study the samples were removed, sectioned and examined for microhardness, caries-lesion area measurements on the polarized light microcopy and morphological analyses on SEM. Variance analysis and the Fisher test were performed for the statistical analysis of the data obtained from the microhardness test (KHN) (&alpha;= 5%). The control group was statically different from G3 and G4, which present higher microhardness values and were statistical similar between them. The data of microhardness from the depth of surface were greater in proportion of distance from the surface, as 20&micro;m <30&micro;m <40&micro;m <50&micro;m. Wilcoxon test were performed for the statistical analysis of the data obtained from the caries-lesion area measurements (mm2) (= 5%) and all the groups were statically similar. Considering the results obtained from the both of studies can be concluded that the laser CO2 and Nd:YAG were able to increase the enamel acid resistance on the surface of pits and fissures.

This thesis covers the individual work of Michael Chin as part of the sponsored research project funded by the U.S. State Department in support of a computational design of a "Mobile Pit Verification System" (MPVS), a mobile “drive by” passive radiation detection system to be applied in special nuclear materials (SNM) storage facilities for validation and compliance purposes. The MPVS system is intended to enable a comprehensive, rapid verification and validation of stored nuclear weapon core physics packages containing SNM, or so-called “weapon pits,” in weapon materials and stockpile storage facilities. The MPVS platform is designed to move at a constant speed and accumulate a signal for each stored weapon pit container. The gamma detector was selected to be a 4 × 4 × 8 cubic inch CsI detector while the neutron detector array designed for the “Transport Simulation and Validation of a Synthetic Aperture SNM Detection System (“T-SADS”) project was used in conjunction with this work; T-SADS was a 3 year project funded by DOE-NNSA which was completed on May 2013. The computational design effort for this project was completed in April 2013, and leveraged novel computational radiation transport methods, algorithms, and SNM identification methods, including a synthetic aperture collection approach, and a new gamma ratio methodology for distinguishing between naturally occurring radiation materials and weapon class SNM materials. Both forward and adjoint transport methods were utilized to characterize the adjoint reaction rate as a function of inter-source spacing, collimation thickness, linear and angular field of view, source age, source type, source geometry, and mobile platform speed. The integrated count was then compared with background radiation and the associated probabilities of detection and false alarm were then computed. Publications resulting from this research were published in PHYSOR 2012, presented at the 53rd annual Proceedings of the INMM, and at the Mathematics & Computation 2013 Conference.

Sand Pits have great potential to restore via spontaneous succession. There are not many studies of the development of soils in sand pits; therefore, this work focuses on the development of soil properties in sand pits comparing technically reclaimed sites and sites with primary succession. 120 samples were collected at fourteen sand pits in South Bohemia and selected soil properties were assessed. The surveyed plot were grouped according to age, and the successional and technically reclaimed sites were distinguished. The results were evaluated by analysis of variation and regression analysis. The differences in soil bulk density, pH, thickness of soil organic horizon, Cox, N and C/N ratio between reclaimed and spontaneously restored sites of different age were analysed. The bulk density and pH decrease significantly on successional sites; however, the reclaimed sites do not show signifiant differences. Organic horizon thickness increases with age on both types of sites.Cox, N and C/N ratio do not show significant influence age. Lower values of Cox, N and C/N were measured in initial stages of succession. On the reclaimed sites there is almost no change in values of Cox, N and C/N ratio, because of the occurrence of nutrient-richer substráte used during technical reclamation. Keywords: soil...

Ce travail porte sur l’étude des transformations induites par les procédés industriels (TIPI) dans le domaine de l’industrie pharmaceutique. Il se focalise sur le procédé de compression directe et sur deux principes actifs modèles qui sont la caféine et la carbamazépine. Des méthodes de caractérisations expérimentales des transitions de phases dans les comprimés ont été développées. La densité des comprimés a été mesurée par tomographie à rayons X et évaluée en surface par micro-indentation. Des méthodes thermiques telles que l’ACD et l’ATG ont été utilisées pour estimer les transformations dans tout le volume des comprimés. La spectroscopie Raman à basses fréquences a été appliquée pour la première fois pour cartographier la surface des comprimés. La spectroscopie Raman à hautes fréquences a été développée dans le but d’augmenter le nombre de données et d’automatiser le traitement des spectres. La transformation de la caféine forme I (métastable) en forme II (stable) nécessite plusieurs années dans les conditions ambiantes. Les investigations menées sur la caféine I ont révélé que la transition est induite par la compression directe car une transformation partielle en forme II est mesurée dans tout le volume du comprimé. La transformation continue au sein du comprimé lors de son stockage et le taux de transformation reste supérieur à celui de la poudre de caféine forme I non comprimée. Les quantifications misent en place par ACD et spectroscopie Raman à basses fréquences ont montré des transformations de la forme I dans tout le volume des comprimés et leur valeur est indépendante de l’intensité de la pression de compression. De plus, les deux formes de la caféine coexistent à l’échelle micrométrique, ce qui tend à prouver que des cristallites de forme II apparaissent dans tous les grains de caféine. La caféine formulée avec de la cellulose microcristalline présente un comportement plastique lors de la compression. La tomographie à rayons X révèle l’existence d’une zone locale de densité plus élevée au niveau des parois latérales, sans que ceci influe localement sur le taux de transition de la caféine. L’emploi d’une caféine calibrée entraine un comportement plus fragmentaire, qui semble réduire le taux de transformation mesuré. Aucune transformation de phase solide de la carbamazépine dihydrate n’a été décelée par ATG et spectroscopie Raman dans les comprimés fabriqués. Il semble que ce principe actif soit stable en compression directe / The purpose of this study was to improve the understanding of process induced transformations (PITs) in the field of the pharmaceutical industry. This present study is focused on the direct compression process applied to two model active molecules named caffeine and carbamazepine. Experimental characterization methods of phase transitions in the tablets were developed. Densities inside the tablets were measured by X-ray computed micro-tomography and by micro-indentation at the surface. Thermal methods for DSC and TGA were applied in order to estimate transformation degrees of tablet parts. Low frequencies micro-Raman Spectroscopy (MRS) was used for the first time as a way for polymorphs mapping. Raman spectroscopy was also developed in the high frequencies range to increase the analyzed part area and to computerize the spectra treatment. Caffeine form I is transformed naturally toward caffeine form II but this transition can take many years at room temperature. Our investigations have shown that the direct compression process induced a partial transition of caffeine I toward caffeine II. Phase transition degree stayed higher in the tablet than in the non-compressed powder during two years. Quantification process was set up for DSC and low frequencies MRS. It was found that the pressure level did not influenced the transition degree. Moreover, both polymorphs coexist at the micrometer scale in all caffeine particles. Caffeine formulated with micro-crystalline cellulose exhibits a plastic behavior under compaction. X-ray tomography revealed higher densities zones next to the tablet slides but any impact on the transition degree was detected. The use of calibrated caffeine particles led to a more brittle behavior and seemed to decrease the transition degree. The investigations on carbamazepine dihydrate did not show any phase transformation of this active molecule induced by direct compression

Com o intuito de estudar in vivo a reprodutibilidade e a comparação de dois índices visuais (Ekstrand et al. (1998) ? E e Nyvad; Machiulskiene e Baelum (1999) ? N) e as medidas de fluorescência a laser AGNOdent®,KaVo - DD) na detecção de sulcos e fossetas descoloridos, um único examinador treinado, após a obtenção do consentimento livre e esclarecido de 28 pacientes, atribuiu os escores E, N e médias de fluorescência a laser de 190 molares decíduos com e sem descoloração em sulcos e fossetas oclusais. A reprodutibilidade dos índices visuais foi calculada a partir do teste kappa Cohen e kappa ponderado (kp), enquanto para as médias do DD foi calculado o índice de correlação de Pearson (rp). Para a comparação entre os índices visuais ainda se calculou a correlação de Spearman (rcs) e para a correlação entre os índices visuais e as médias do DD, foram aplicados o teste t de Student para as dicotomizações de presença de lesão, descoloração e atividade. Finalmente, foi calculada a análise de variância (ANOVA) para comparação entre as médias do DD e os graus de severidade das lesões. A reprodutibilidade dos índices visuais foi substancial (kpE = 0,645) e (kpN = 0,634) e as médias do DD apresentaram correlação de Pearson significativa e altamente positiva (rp = 0,930). A comparação entre os índices visuais também foi positiva e significativa principalmente quanto à severidade (rcs = 0,623) e nas dicotomizações para a presença de lesão (rcs = 0,765) e descoloração (rcs = 0,757). O teste t de Student para as comparações entre os índices e as médias do DD também se apresentaram significativos (p < 0,001) para presença de lesão e descoloração ao contrário dos resultados para atividade. A análise de variância entre os graus de severidade dos índices visuais e as médias do DD mostrou diferenças estaticamente significativas apenas entre os graus de severidade 0 e 1 (E - 2a) para o índice E e 0, 1 (N - 4) e 2 (N - 5) para o índice N. Conclui-se, para sulcos e fossetas descoloridos de molares decíduos, que (1) ambos os métodos (visuais e de fluorescência a laser) mostraram-se confiáveis (2) o DD foi capaz de diferenciar tecidos hígidos de lesões com descoloração e de (3) inativas intactas ou com microcavidades em esmalte. / Aiming at developing an in vivo study of the reproducibility and correlation of two visual indexes (Ekstrand et al. (1998) ? E and Nyvad; Machiulskiene and Baelum (1999) ? N) and the measures of laser fluorescence (DIAGNOdent®,KaVo - DD) for the detection of decolorised pits and fissures, a single trained examiner, after the free and aware consent of 28 patients, opened the scores E, N and laser fluorescence averages of 190 primary molars with and without occlusal discoloration in pits and fissures. The reproducibility of the visual indexes was calculated with basis on the kappa Cohen and weighted kappa (wk) tests, while for the DD averages the Perason´s correlation (rp) was calculated. To provide a comparison among the visual indexes, the Sperman´s correlation (rcs) was calculated, and for the correlation among the visual indexes and the DD averages, the Student´s t test and the one-way analysis of variance (ANOVA) were applied to compare the DD averages and the degree of severity of the lesions. The reproducibility of the visual indexes was substantial (wkE= 0,645) and (wkN= 0,634); the DD averages presented a significant and highly positive Pearson´s correlation (rP= 0,930). The comparison among the visual indexes proved to be positive and significant, mainly in relation to the severity (rcs= 0,623) and the dichotomisations for the presence of lesion (rcs= 0,765) and discoloration (rcs= 0,757). The Student´s t test of for the comparisons among the indexes and the DD averages also proved to be significant (p < 0,001) for the presence of lesion and discoloration, contrary to the activity results. The one-way analysis of variance (ANOVA) among the degrees of severity and DD averages showed significant differences only at the degrees 0 and 1 (E ? 2a) of the E index and 0, 1 (N ? 4) and 2 (N ? 5) of the N index. The conclusions for pits and fissures with discoloration in primary molars are that (1) both methods (visual and laser fluorescence) were reliable (2) the DD was able to diferenciatte sound tissues from lesions with discoloration and (3) inactive intact or with microcavities lesions at the enamel level.