Greenhouse gas balance due to the conversion of sugarcane areas from burned to green harvest in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Greenhouse gas balance due to the conversion of sugarcane areas from burned to green harvest, considering other conservationist management practices

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Violet-blue emissions due to frequency up-conversion in Nd3+-doped fluoroindate glasses

We report the observation of intense frequency up-conversion in Nd3+-doped fluoroindate glasses pumped by the second harmonic of a cw mode-locked Nd: YAG laser. Mechanisms for generating the observed emissions are discussed.

Remark on the muonium to antimuonium conversion in a 3-3-1 model

Here we analyze the relation between the search for muonium to antimuonium conversion and the 3-3-1 model with doubly charged bileptons. We show that the constraint on the mass of the vector bilepton obtained by experimental data can be evaded even in the minimal version of the model since there are other contributions to that conversion. We also discuss the condition for which the experimental data constraint is valid. ©2000 The American Physical Society.

Infrared to visible up-conversion emission in Er3+/Yb 3+ codoped fluoro-phosphate glass-ceramics

Erbium Er3+ and ytterbium Yb3+ codoped fluoro-phosphate glasses belonging to the system NaPO3-YF 3-BaF2-CaF2 have been prepared by the classical melt-quenching technique. Glasses containing up to 10 wt% of erbium and ytterbium fluorides have been obtained and characterized using differential scanning calorimetry (DSC) and UV-visible and near-infrared spectroscopy. Transparent and homogeneous glass-ceramics have been then reproducibly synthetized by appropriate heat treatment above glass transition temperature of a selected parent glass. Structural investigations of the crystallization performed through X-ray diffractometry (XRD) and scanning electron microscopy (SEM) have evidenced the formation of fluorite-type cubic crystals based during the devitrification process. Finally, infrared to visible up-conversion emission upon excitation at 975 nm has been studied on the Er3+ and Yb 3+ codoped glass-ceramics as a function of thermal treatment time. A large enhancement of intensity of the up-conversion emissions-about 150 times- has been observed in the glass-ceramics if compared to the parent glass one, suggesting an incorporation of the rare-earth ions (REI) into the crystalline phase. © 2012 The American Ceramic Society.

Visible to infrared energy conversion in Pr3+-Yb3+ co-doped fluoroindate glasses

Processes involving visible to infrared energy conversion are presented for Pr3+-Yb3+ co-doped fluoroindate glasses. The emission in the visible and infrared regions, the luminescence decay time of the Pr 3+:3P0 → 3H4 (482 nm), Pr3+:1D2 → 3H6 (800 nm), Yb3+:2F5/2 → 2F 7/2 (1044 nm) transitions and the photoluminescence excitation spectra were measured in Pr3+ samples and in Pr3+-Yb 3+ samples as a function of the Yb3+ concentration. In addition, energy transfer efficiencies were estimated from Pr3+: 3P0 and Pr3+:1D2 levels to Yb3+:2F7/2 level. Down-Conversion (DC) emission is observed due to a combination of two different processes: 1-a one-step cross relaxation (Pr3+:3P0 → 1G4; Yb3+:2F7/2 → 2F5/2) resulting in one photon emitted by Pr3+ (1G4 → 3H5) and one photon emitted by Yb3+ (2F7/2 → 2F5/2); 2-a resonant two-step first order energy transfer, where the first part of energy is transferred to Yb3+ neighbor through cross relaxation (Pr3+:3P0 → 1G4; Yb3+:2F7/2 → 2F5/2) followed by a second energy transfer step (Pr 3+:1G4 → 3H4; Yb3+:2F7/2 → 2F5/2). A third process leading to one IR photon emission to each visible photon absorbed involves cross relaxation energy transfer (Pr3+: 1D2 → 3F4; Yb 3+:2F7/2 → 2F5/2). © 2013 Elsevier B.V. All rights reserved.

Infrared to visible up-conversion in biocellulose yttrium vanadate nanoparticle composite membranes. Demonstration of chloroaluminum phthalocyanine light emission under up-converted light excitation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Greenhouse gas balance in the conversion from extensive pasture to other agricultural systems in Andean region of Colombia

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Bio-energy conversion cost: a new index to evaluate the bioeconomic eficiency

This study evaluated a nonlinear programming excel workbook PPFR (http://www.fmva.unesp.br/ppfr) for determining the optimum nutrient density and maximize margins. Two experiments were conducted with 240 one-day-old female chicks and 240 one-day-old male chicks distributed in 48 pens (10 chicks per pen, 4 replicates) in a completely randomized design. The treatments include the average price history (2009s and 2010s) for broiler increased and decreased by 25% or 50% (5 treatments to nonlinear feed formulation) and 1 linear feed formulation. Body gain, feed intake, feed conversion were measured at 21, 42 and 56 d of age. Chicks had ad libitum access to feed and water in floor pens with wood shavings as litter. The bio-economic Energy Conversion [BEC= (Total energy intake*Feed weighted cost per kg)/ (Weight gain*kg live chicken cost)] was more sensitive for measuring the bio-economic performance for broilers, and especially with better magnitude. This allowed a better assessment of profitability, the rate of growth and not just energy consumption, the production of broilers, by incorporating energy consumption, allowing for more sensitivity to the new index (BEC). The BEC was demonstrated that the principle of nonlinear formulation minimizes losses significantly (P<0.05), especially under unfavorable conditions the price of chicken in the market. Thus, when considering that a diet of energy supply shows up as the most expensive item of a formulation, it should compose necessarily the formula proposed for a bio-economic index. Thus, there is need to evaluate more accurately, not only the ingredients of a ration, but the impact of nutrients on the stability of a solution, mainly due to the energy requirement. This strategy promotes better accuracy for decision making under conditions of uncertainty, to find alternative post-formulation. From the above, both weight gain and feed conversion, as traditional performance indicators, cannot finalize or predict a performance evaluation of an economic system creating increasingly intense and competitive. Thus, the energy concentration of the diet becomes more important definition to feed formulator, by directly impact profit activity by interactions with the density of nutrients. This allowed a better evaluation of profitability, the rate of energy performance for broilers, by incorporating the energy consumption formula, allowing more sensitivity to the new index (BEC). These data show that nonlinear feed formulation is a toll to offer new opportunities for poultry production to improved profitability.