128 research outputs found
Regional mantle heterogeneity regulates melt production along the Réunion hotspot-influenced Central Indian Ridge
No full textTo ascertain factors controlling melt production along a typical distal, 'hotspot-interacting' mid-ocean ridge, we investigated the extent and distribution of both plume-related and plume-unrelated basalt from the central Indian ridge (CIR) between 15°S and 20°S. Comprehensive geochemical data of fresh-quenched volcanic glasses and basalts were used. Variation of Sr, Nd, and Pb isotopic compositions and Nb/Zr, Ba/Nb, and Ba/La content were interpreted by mixing of three melt end members: the Indian depleted MORB mantle derived melt; radiogenic and enriched melt derived from source mantle for Rodrigues Ridge and the intermediate series of Mauritius Island (RE2, radiogenic enriched component 2); and radiogenic but depleted melt derived from source mantle for Gasitao Ridge (RD, radiogenic depleted component). On the basis of quantitative mantle melting and melt mixing model, results show that sources for RE2 and RD are geochemically distinct from those of the Réunion plume (RE1, radiogenic enriched melt component 1). Moreover, the geochemical variation of MORB of 15°S to 20°S is unrelated to contamination of the upper mantle by the Réunion plume. These results suggest strongly that plume-unrelated heterogeneity is widespread throughout the upper mantle. The chemical characteristics of RE2 are remarkably pronounced in basalt from the central portion of ridge segment 16 around 18°S, suggesting substantial magma production. The influence of RE2 decreases along with decreasing magma production to the north, and is only slightly identifiable in basalt from the northern part of segment 18. Although the influence of RE2 decreases somewhat to the south, basalts with extreme RE2 signature were produced in the center of segment 15 around 19°S, where magma production is high. In contrast to RE2, the geochemical signature of RD in basalt is geographically limited to two localities: the south end of segment 18 and the center of segment 15. However, these observations reveal that both RE2 and RD contribute strongly to magma production on segment 15. Results show that melting of ancient recycled plate materials with a low melting point regulates voluminous magma production along the CIR
Ferrite loaded DBD plasma device
No full textSem informaçãoAn atmospheric pressure plasma jet device with dielectric barrier discharge was built using low cost 5C22 thyratron valve and ferrite transformer. The ferrite transformer increases the intensity about four times the primary pulse and lengthens the high voltage pulse, keeping the rise time of the thyratron pulse. Spectrometer measurement shows excited nitrogen molecular emissions of second positive system. The most intense nitrogen molecular line, 357.69 nm, was chosen to monitor the time dependence of the discharge. Synthetic temperature, using 380.49 nm line of N2 emission and SpecAir simulation, shows plasma gas temperature of 300 K. To corroborate this low temperature, the plasma jet is applied to human tongue with no harm or bad physical feeling.An atmospheric pressure plasma jet device with dielectric barrier discharge was built using low cost 5C22 thyratron valve and ferrite transformer. The ferrite transformer increases the intensity about four times the primary pulse and lengthens the high voltage pulse, keeping the rise time of the thyratron pulse. Spectrometer measurement shows excited nitrogen molecular emissions of second positive system. The most intense nitrogen molecular line, 357.69 nm, was chosen to monitor the time dependence of the discharge. Synthetic temperature, using 380.49 nm line of N2 emission and SpecAir simulation, shows plasma gas temperature of 300 K. To corroborate this low temperature, the plasma jet is applied to human tongue with no harm or bad physical feeling.451132137Sem informaçãoSem informaçãoSem informaçãoGraves, D.B., (2012) J Phys D Appl Phys, 45, p. 42Laroussi, M., Akan, T., (2007) Plasma Process Polym, 4, pp. 777-788Chaker, M., Moisan, M., Zakrewski, Z., (1986) Plasma Chem Plasma Process, 6, pp. 79-96Bloyet, E., Leprince, P., Llamas Brasco, M., Marec, J., (1981) Phys Lett, 8, pp. 391-392Gradov, O.M., Stenflo, L., (2001) J Plasma Phys, 65, pp. 73-77Yanguas-Gil, A., Focke, K., Benedikt, J., von Keudella, A., (2007) J of Appl Phys, 101, p. 103307Wang, C., Srivastava, N., (2010) Eur Phys J D, 60, pp. 465-477Walsh, J.L., Shi, J.J., Kong, M.G., (2006) Appl Phys Lett, 88, p. 171501Pei, X., Lu, X., Liu, J., Liu, D., Yang, Y., Ostrikov, K., Paul, A., Pan, Y., (2012) J Phys D Appl Phys, 45, p. 165205. , 5ppMello, C.B., Kostov, K.G., Machida, M., Hein, L.R.O., Campos, K.A., (2012) IEEE Trans Plasma Sci, 40, pp. 2800-2805(1992) Aramaki, , PhD thesis IF-USP: DecemberMachida, M., Lebedev, S.V., Moshkalyov, S.A., Campos, D.O., Berni, L.A., (1996) Braz J Phys, 26, p. 04Gribble, R.F., Proceedings of symposium on engineering problems of fusion research, LANL, DI-5-1 TO DI-5-3, Los Alamos, N (1969) Los AlamosLu, X., Naidis, G.V., Laroussi, M., Ostrikov, K., (2014) Physics Reports, 540, pp. 123-166Lu, X., Wu, S., Paul, K., Chu, D., Liu, Y., Pan, Plasma Sources Sci (2011) Technol, 65009 (5), p. 20Lu, X., Cao, Y., Yang, P., Xiong, Q., Xiong, Z., Xian, Y., (2009) Y. Pan, IEEE Transactions on Plasma Science, 37 (5)Bruggemann, P., (2013) J Phys D Appl Phys, 46, p. 464001http://www.specair-radiation.net/Morfill1, G.E., Kong, M.G., J (2009) L. Zimmermann, New J Phys, 11Fridman, G., Friedman, G., Gutsol, A., A. B. Shekhter, V (2008) N. Vasilets, A. Fridman, Plasma Process Polym, 5, pp. 503-533Vandamme, M., Robert, E., Dozias, S., Sobilo, J., Lerondel, S., Le Pape, A., Pouvesle, J.M., (2011) Plasma Med, 1, pp. 27-43The author wish to thank Dr. Vadym Prysiazhnyi, DFQ-FEG-UNESP, who helped to perform DBD power measurements, and Prof. Dr. Júlio Akashi Hernandes to localize the reference [13]
All centralising monoids on the set {0, 1, 2}, including their witnesses
No full textThis dataset contains code and data to produce a list of all 192 centralising monoids on the set , including a witness for each of them. This gives a computational verification of the classification of centralising monoids published by Machida and Rosenberg in 2012 and 2013. Furthermore, some of the cpp-files and the context files form supplements to the bachelor dissertation of the second-named author. The code and the computed data contained in this upload also supplement the conference article that appeared in ICFCA 2023.
A detailed description of the files in the dataset can be obtained from the file cent_mons3_witn.pdf (the code source for this file is given in cent_mons3_witn.tex)
Optimum arrangement of seismic intensity monitoring points for immediate estimation system of wide-area distribution of seismic intensity
No full textSingularities of improper affine spheres and surfaces of constant Gaussian curvature
No full textWe study the equation for improper (parabolic) affine spheres from the view point of contact geometry and provide the generic classification of singularities appearing in geometric solutions to the equation as well as their duals. We also show the results for surfaces of constant Gaussian curvature and for developable surfaces. In particular we confirm that generic singularities appearing in such a surface are just cuspidal edges and swallowtail
Testing the randomness in the sky-distribution of gamma-ray bursts
No full textWe have studied the complete randomness of the angular distribution of gamma-ray bursts (GRBs) detected by the Burst and Transient Source Experiment (BATSE). Because GRBs seem to be a mixture of objects of different physical nature, we divided the BATSE sample into five subsamples (short1, short2, intermediate, long1, long2) based on their durations and peak fluxes, and we studied the angular distributions separately. We used three methods, Voronoi tesselation, minimal spanning tree and multifractal spectra, to search for non-randomness in the subsamples. To investigate the eventual non-randomness in the subsamples, we defined 13 test variables (nine from the Voronoi tesselation, three from the minimal spanning tree and one from the multifractal spectrum). Assuming that the point patterns obtained from the BATSE subsamples are fully random, we made Monte Carlo simulations taking into account the BATSE's sky-exposure function. The Monte Carlo simulations enabled us to test the null hypothesis (i.e. that the angular distributions are fully random). We tested the randomness using a binomial test and by introducing squared Euclidean distances in the parameter space of the test variables. We concluded that the short1 and short2 groups deviate significantly (99.90 and 99.98 per cent, respectively) from the full randomness in the distribution of the squared Euclidean distances; however, this is not the case for the long samples. For the intermediate group, the squared Euclidean distances also give a significant deviation (98.51 per cent)
Sobre la autenticidad de algunas "cabezas reducidas" de los jíbaros.. Anales del Instituto Nacional de Antropología e Historia. Num. 47 Tomo XVIII (1965) Sexta Época (1939-1966)
No full textDuggins. O. H. y M. Trotter. Age Changes in Head Hair From Birth to Maturity, ll. Medullation in Hair of Children. American Journal of Physical Anthropology, Vol. 8, No. 3, 1950, pp. 399-415.Ellis, R. A. y W. Montagna. The Skin Primates, VI. The Skin of the Gorila (Gorilla gorilla). American Joumal of Physical Anthropology, Vol. 20, No. 2, 1962, pp. 79-93.Garn, S. Hair Texture: Its Definition, Evaluation and Measurement. American Joumal of Physical Anthropology, Vol. 8, No. 4. 1950. pp. 453-63.Ham, A. W. y Thomas Sydney Leeson. Tratado de Histología. México, 1963.Hartshorne, N. H. y A. Stuart. Cristals and the Polarising Microscope. London, 1960.Hooton, E. A. Up From the Ape. New York, 1947.Kimber, C. D. Manual de Anatomía y Fisiología. México, 1960.Machida H., E. Pirkins y W. Montagna. The Skin of Primates, XXIII. A Comparative Study of the Skin of the Green Monkey (Cercopithecus aethiops) and the Sykes' Monkey (Cercopithecus mitis). American Journal of Physical Anthropology, Vol. 22, No. 4, 1964, pp. 453-65.Montilla Díaz, R. Ganado Lanar. México, 1955, pp. 299-341
The affordances and challenges of drama pedagogies among young learners in the EFL context: A Qualitative Research Synthesis
No full textRecent studies in the 'Science of Learning' indicate that collaborative learning can outweigh the effectiveness of learning individually. Drama approaches are typical collaborative activities and researchers in TESOL report the effectiveness of drama approaches.
The present study examined affordances and challenges of drama pedagogies among young learners via QRS to aim providing an overview of drama approaches.
The results indicate drama approaches have mainly four affordances in English learning: raising learners' motivation, providing collaborative opportunities, increasing language skills, and accompanying body movements stimulate attention, memory, and left brain. (See Appendix 4 and 5 on pages 103-104)
Even though there are some challenges, the author recommends practitioners in elementary and junior high schools to develop learners' communication skills in English
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