2,201 research outputs found
Electronic Structure Of Amorphous Si3n4 In The Cluster-bethe-lattice Approximation
We present a calculation of the electronic structure of amorphous Si3N4, using a model tight-binding Hamiltonian with a basis set of Si 3s and 3p, and N 2s and 2p orbitals. Clusters of 13 atoms, centered at either a Si or a N atom, are constructed using structural data from crystalline 2-Si3N4. These clusters are employed to generate a self-consistent transfer-matrix approximation for an infinite effective medium (Bethe lattice). The local and average densities of states are evaluated using standard one-particle Greens operator techniques. We also simulate photoemission spectra by weighting orbitally decomposed partial densities of states with appropriate photoemission cross sections. Our results are in good agreement with recent experimental data. © 1985 The American Physical Society.32128332833
Photo Acoustic Study Of Plants Exposed To Varying Light Intensity Growth Conditions: Spectral And Morphological Changes
In this paper we describe results of photo acoustic (PA) measurements carried out on various plants exposed to varying light intensity conditions. Depending on the species and light intensity conditions, the PA absorption spectra show differences in peaks associated with pigments and the cuticle. These differences are related to the spatial distribution of the pigments that differs from plant to plant. We have also performed systematic study of oxygen evolution at different wavelengths. The obtained oxygen spectra are equivalent to the action spectra usually acquired by determining the CO2 uptake and energy storage. The intensities of oxygen spectra exhibit differences depending on distinct morphology of plant. © EDP Sciences.125745748Marquezini, M.V., Cella, N., Mansanares, A.M., Vargas, H., Miranda, L.C.M., (1991) Meas. Sci. Technol., 2, p. 396Barja, P.R., Mansanares, A.M., (1998) Instrum. Sci. Technol., 26, p. 209Barja, P.R., Mansanares, A.M., Da Silva, E.C., Magalhães, A.C.N., Alves, P.L.C.A., (2001) Photosynthetica, 39, p. 489Salisbury, F.B., Ross, C.W., (1992) Plant Physiology, , Wadsworth Publishing Company, CaliforniaClark, J.B., Lister, G.R., (1975) Plant Physiol., 55, p. 401Carpentier, R., Larue, B., Leblanc, R.M., (1983) J. Physique Colloque C6, 44 (10 SUPL), pp. 355-360Veeranjaneyulu, K., Charland, M., Charlebois, D., Leblanc, R.M., (1991) Photosynth. Res., 30, p. 13
Galhas De Insetos Da Serra Geral, Caetité, Bahia, Brasil
We inventoried and characterized the kinds of gall, gall-inducing insects and host plants from Serra Geral between August 2013 and July 2014. Two phytophysiognomies, cerrado sensu stricto and caatinga-cerrado, were examined monthly along transects during ca. 4 hours per visit, totaling 48 hours of sampling effort. A total of 49 gall morphotypes were found on 14 species of host plants in 18 genera and 13 families. Fabaceae and Malpighiaceae were the families with the most galls, with 22 and 10 gall morphotypes, respectively. The genera of host plant with the greatest richness of galls were Copaifera L. (n=10), Bauhinia Benth. (n=6), and Mimosa L. (n=5). Galls were found on leaves, buds and stems. The majority of the galls were globoid, glabrous, isolated, and one-chambered. The inducers belong to Coleoptera, Diptera, and Lepidoptera, Cecidomyiidae (Diptera) being the most frequent and diverse gall-inducers. The associated fauna included parasitoids (Hymenoptera), successors (Formicidae), and predators (Pseudoscorpiones), obtained from 13, 2, and 1 gall morphotypes, respectively. Five plant taxa are recorded as hosts of gall-inducing insects for the first time. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.16111
Phase-resolved Photoacoustic Spectroscopy And Epr Investigation Of Mno2- And Coo-doped Soda-lime Glasses
A discussion on the use of the phase shifts of the photoacoustic signal of different constituents of a composite sample for resolving their individual spectra is presented. It is experimentally shown that as long as we are interested in a qualitative analysis the method is simple and fast. For a quantitative analysis in which the nonradiative relaxation time and the characteristic diffusion time within the optical-absorption depth are sought, the method presents some limitations. This is demonstrated using MnO2- and CoO-doped soda-lime silica glass samples. © 1989 The American Physical Society.40318801884CAS; Chinese Academy of Sciences; DFG; Chinese Academy of Sciences; NRF; Chinese Academy of Sciences; NSFC; Chinese Academy of Sciences; PSI; Chinese Academy of Sciences; RAS; Chinese Academy of Sciences; RFBR; Chinese Academy of Sciences; RPF; Chinese Academy of Sciences; STFC; Chinese Academy of Science
Thermal Diffusivity Of Palladium-hydrogen Systems At Room Temperature Using Photothermal Detection
We report results of measurements on the thermal diffusivity, specific heat and electrical resistivity of hydrogenated-palladium samples. It is shown that repetition of the hydrogenation process with the same sample induces aging effects, which lead to erroneous results. The results for the thermal-property measurements on single-cycled palladium samples reflected a phase transition between -PdH and -PdH as the hydrogen concentration is increased. © 1992 The American Physical Society.4595031503
Reguladores Vegetais E Sombreamento Na Emergência De Plântulas De Macadâmia
This study aimed to evaluate the effect of plant growth regulators and shading on seed germination of macadamia nut trees. The experiment was conducted in a seedling production nursery of the company "QueenNut Macadâmia" located in the "Palmeiras" Farm, Dois Córregos, São Paulo (SP) state, Brazil. The Treatments were T1: water (control) under a shading screen, T2: GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) at 200 mL L-1 under a shading screen, T3: Promalin® at 400 mL L-1 under a shading screen, T4: gibberellic acid (GA3) + kinetin (Kt) + 3- indolebutyric acid (IBA) - Stimulate® at 5 mL kg-1 seeds under a shading screen, T5: Stimulate® at 10 mL kg-1 of seeds under a shading screen, and T6: water (control) under no shading screen. Seeds were soaked in the solutions or in water containing plant growth regulators for 24 hours. Then, they were dried and sown in sand. 450 seeds were used for each treatment. The evaluations began from seedling emergence by counting the total number of seedlings per treatment. A high average of macadamia nut tree seedling emergence was obtained in the treatments GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 400 mL L-1 with Sombrite® (75.7%), GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 200 mL L-1 (72.6%) Sombrite® and water (control) without Sombrite® (71.5%). © 2016, Universidade Federal de Uberlandia. All rights reserved.3251263126
Desenvolvimento, Produtividade E Atributos Qualitativos De Cultivares De Cana-de-açúcar Fertirrigadas Por Gotejamento Subsuperficial
The present study aimed to evaluate the development, yield and quality of four sugarcane cultivars fertigated by subsurface drip system. The experiment was carried out in Campinas-SP, Brazil, from January 2012 to November 2013, with the cultivars SP79-1011, IACSP94-2101, IACSP94-2094 and IACSP95-5000 subjected to daily irrigations. The irrigations depths were applied to bring soil moisture to field capacity. Soil moisture was monitored using soil moisture probes. Samples were collected along the crop cycle in order to evaluate crop development and yield, at the end of the first and second ratoons. Stalk height showed good correlation for the estimation of crop yield, with R2 equal to or higher than 0.96. The cultivar IACSP95-5000 showed the highest yield in the first ratoon. In the second ratoon the highest yield was observed in IACSP94-2101, followed by IACSP95-5000 and SP79-1011. Considering the yield results associated with the technological analysis, such as soluble solids content and apparent sucrose, the cultivar IACSP95-5000 excelled the others in the cultivation under subsurface drip irrigation. © 2016, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.20652553
Photoacoustic Assessment Of The In Vivo Genotypical Response Of Corn To Toxic Aluminium
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)[No abstract available]1153341343ACRL; Association of College and Research Libraries; CAPES; Association of College and Research LibrariesCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
Electron Spin Resonance G Shift In Gd5 Si4, Gd5 Ge4, And Gd5.09 Ge2.03 Si1.88
Gd5 Si4, Gd5 Ge4, and Gd5.09 Ge2.03 Si1.88 compounds were studied by electron spin resonance. The arc-melted samples were initially characterized by optical metallography, x-ray diffraction, and static magnetization measurements. The electron spin resonance results show a negative paramagnetic g shift for Gd5 Si4 and Gd5.09 Ge2.03 Si1.88, and a smaller positive one for Gd5 Ge4. The values of the exchange parameter (j) between the localized Gd-4f spins and the conduction electrons are obtained from the g shifts. These values are positive and of the same order of magnitude for Gd5 Si4 and Gd5.09 Ge2.03 Si1.88, and negative one order of magnitude smaller for Gd5 Ge4. The electron spin resonance data were interpreted considering the strongly bottlenecked solution of the coupled Bloch-Hasegawa equations. © 2006 The American Physical Society.7314Pecharsky, V.K., Gschneidner Jr., K.A., (1997) Phys. Rev. Lett., 78, p. 4494. , PRLTAO 0031-9007 10.1103/PhysRevLett.78.4494Pecharsky, V.K., Gschneidner Jr., K.A., (1997) J. Alloys Compd., 260, p. 98. , JALCEU 0925-8388 10.1016/S0925-8388(97)00143-6Choe, W., Pecharsky, V.K., Pecharsky, A.O., Gschneidner Jr., K.A., Young Jr., V.G., Miller, G.J., (2000) Phys. Rev. Lett., 84, p. 4617. , PRLTAO 0031-9007 10.1103/PhysRevLett.84.4617Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., (2000) Phys. Rev. B, 62, p. 14625. , PRBMDO 0163-1829 10.1103/PhysRevB.62.R14625Szade, J., Skorek, G., (1999) J. Magn. Magn. Mater., 196-197, p. 699. , JMMMDC 0304-8853Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., (1999) Phys. Rev. B, 60, p. 7993. , PRBMDO 0163-1829 10.1103/PhysRevB.60.7993Harmon, B.N., Antonov, V.N., (2002) J. Appl. Phys., 91, p. 9815. , JAPIAU 0021-8979 10.1063/1.1461896Levin, E.M., Pecharsky, V.K., Gschneidner Jr., K.A., Miller, G.J., (2001) Phys. Rev. B, 64, p. 235103. , PRBMDO 0163-1829 10.1103/PhysRevB.64.235103Skorek, G., Deniszczyk, J., Szade, J., (2002) J. Phys.: Condens. Matter, 14, p. 7273. , JCOMEL 0953-8984 10.1088/0953-8984/14/30/316Samolyuk, G.D., Antropov, V.P., (2002) J. Appl. Phys., 91, p. 8540. , JAPIAU 0021-8979 10.1063/1.1455614Pecharsky, V.K., Samolyuk, G.D., Antropov, V.P., Pecharsky, A.O., Gschneidner Jr., K.A., (2003) Solid State Chem., 171, p. 57. , 29CBA6Pires, M.J.M., Magnus Carvalho G, A., Gama, S., Da Silva, E.C., Coelho, A.A., Mansanares, A.M., (2005) Phys. Rev. B, 72, p. 224435. , PRBMDO 0163-1829 10.1103/PhysRevB.72.224435Gama, S., Alves, C.S., Coelho, A.A., Ribeiro, C.A., Persiano, A.I.C., Silva, D., (2004) J. Magn. Magn. Mater., 272-276, p. 848. , JMMMDC 0304-8853Usenko, N.I., Ivanov, M.I., Berezutski, V.V., Polotska, R.I., (1998) J. Alloys Compd., 266, p. 186. , JALCEU 0925-8388Zipper, E., (1982) J. Phys. F: Met. Phys., 12, p. 3123. , JPFMAT 0305-4608Glaunsinger, W.S., (1976) J. Phys. Chem. Solids, 37, p. 51. , JPCSAW 0022-3697 10.1016/0022-3697(76)90179-7Kaczmarska, K., (1996) J. Alloys Compd., 240, p. 88. , JALCEU 0925-8388Barnes, S.E., (1981) Adv. Phys., 30, p. 801. , ADPHAH 0001-8732 10.1080/00018738100101447Taylor, R.H., Coles, B.R., (1975) J. Phys. F: Met. Phys., 5, p. 121. , JPFMAT 0305-4608 10.1088/0305-4608/5/1/017Kaczmarska, K., Kwapulińska, E., Lebarski, A., Zipper, E., Chelkowski, A., (1985) J. Magn. Magn. Mater., 50, p. 101. , JMMMDC 0304-8853Schütz, G., Knülle, M., Wienke, R., Wilhelm, W., Wagner, W., Kienle, P., Frahm, R., (1988) Z. Phys. B: Condens. Matter, 73, p. 67. , ZPCMDN. 0722-3277. 10.1007/BF01312156Kim, J.W., Lee, Y., Wermeille, D., Sieve, B., Tan, L., Bud'Ko, S.L., Law, S., Goldman, A.I., (2005) Phys. Rev. B, 72, p. 064403. , PRBMDO 0163-1829 10.1103/PhysRevB.72.064403Lee, Y., Kim, J.W., Goldman, A.I., Harmon, B.N., (2005) J. Appl. Phys., 97, pp. 10A311. , JAPIAU 0021-8979 10.1063/1.185221
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