Contexto ambiental e aspectos tecnológicos das graxarias no Brasil para a inserção do pequeno produtor na indústria da carne

Neste trabalho são analisadas algumas alternativas tecnológicas para o desenvolvimento de pequenas graxarias destinadas à pequena produção de carne. É considerado que a substituição do conceito de "resíduos animais" pelo conceito de "matéria-prima para graxaria" pode ser amplificada com algumas implementações no processo produtivo, agregando valor aos subprodutos animais, no sentido de uma produção mais limpa, o que reduz o impacto ambiental da atividade e os riscos das más condições higiênicas

Dalton Transactions

p. 6420–6432Chemical reactivity, photolability, and computational studies of the ruthenium nitrosyl complex with a substituted cyclam, fac-[Ru(NO)Cl2(κ3N4,N8,N11(1carboxypropyl)cyclam)]Cl·H2O((1-carboxypropyl)cyclam = 3-(1,4,8,11-tetraazacyclotetradecan-1-yl)propionic acid)), (I) are described. Chloride ligands do not undergo aquation reactions (at 25 °C, pH 3). The rate of nitric oxide (NO) dissociation (kobs-NO) upon reduction of I is 2.8 s−1 at 25 ± 1 °C (in 0.5 mol L−1HCl), which is close to the highest value found for related complexes. The uncoordinated carboxyl of I has a pKa of [similar]3.3, which is close to that of the carboxyl of the non coordinated (1-carboxypropyl)cyclam (pKa = 3.4). Two additional pKa values were found for I at [similar]8.0 and [similar]11.5. Upon electrochemical reduction or under irradiation with light (λirr = 350 or 520 nm; pH 7.4), I releases NO in aqueous solution. The cyclam ring N bound to the carboxypropyl group is not coordinated, resulting in a fac configuration that affects the properties and chemical reactivities of I, especially as NO donor, compared with analogous trans complexes. Among the computational models tested, the B3LYP/ECP28MDF, cc-pVDZ resulted in smaller errors for the geometry of I. The computational data helped clarify the experimental acid-base equilibria and indicated the most favourable site for the second deprotonation, which follows that of the carboxyl group. Furthermore, it showed that by changing the pH it is possible to modulate the electron density of I with deprotonation. The calculated NO bond length and the Ru/NO charge ratio indicated that the predominant canonical structure is [RuIIINO], but the Ru–NO bond angles and bond index (b.i.) values were less clear; the angles suggested that [RuIINO+] could contribute to the electronic structure of I and b.i. values indicated a contribution from [RuIVNO−]. Considering that some experimental data are consistent with a [RuIINO+] description, while others are in agreement with [RuIIINO], the best description for I would be a linear combination of the three canonical forms, with a higher weight for [RuIINO+] and [RuIIINO]

Desenvolvimento e avaliação de um porta-amostra de baixo custo para caracterização elétrica de materiais cerâmicos Development and evaluation of a low cost sample holder for electical characterization of ceramics

<abstract language="eng">Conventional sample holder cells used to the electric characterization of ceramics at high temperature consists of an alumina tube and platinum wires and plates using a complex design. The high cost materials used in the conventional sampler holder cell were replaced by stainless steel and conventional ceramics. The sample holder was validated by characterizing yttria-stabilized-zirconia in a temperature range of 25 to 700 ºC. The results do not present variations, discontinuity or unusual noise in the electric signals. Several samples were characterized without maintenance, which demonstrates that the sample holder is electric and mechanic adequate to be used to electrical characterization of ceramics up to 700 ºC

Astrophysical Journal

p. 1-20A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 1018 eV at the Pierre Auger Observatory is presented. This search is performed as a function of both declination and right ascension in several energy ranges above 1018 eV, and reported in terms of dipolar and quadrupolar coefficients. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Assuming that any cosmic-ray anisotropy is dominated by dipole and quadrupole moments in this energy range, upper limits on their amplitudes are derived. These upper limits allow us to test the origin of cosmic rays above 1018 eV from stationary Galactic sources densely distributed in the Galactic disk and predominantly emitting light particles in all directions

Solar Radiation Components on a Horizontal Surface in a Tropical Coastal City of Salvador

Renewable energy must be prioritized by humankind, mainly if there is an expected increase of 50% in energy consumption by 2030 and climate change scenarios are also confirmed. Urban areas consume 70% of the available energy on the planet. Brazil, the largest country in South America, concentrates more than 85% of its population in urban areas, facing a challenge to increase the renewable power plants in its energy matrix. This work presents the solar radiation components behavior for the city of Salvador to contribute with initiatives for the use of solar energy resource. Firstly, a radiometric platform was implemented to obtain direct measurements of global (EG) and diffuse (EDF) components of incoming solar radiation at the surface. The knowledge of EDF is an important requirement to support photovoltaic system projects, and there is no information on direct measurements of this component in the State of Bahia. The diffuse radiation measurement device (DRMD) was designed and built for this purpose. The measurements of solar radiation components performed in this research were submitted to a specific quality control, statistically analyzed and used to evaluate the performance of different empirical models to represent the behavior of EDF  in the tropical coastal city. The results demonstrate the potential to explore solar energy in the city of Salvador, with annual values of sunshine higher than 2200 h year−1 and average daily intensities of EG  and EDF  equal to 18.7 MJm−2day−1 and 7.35 MJm−2day−1,  respectively. The analysis of the diurnal cycle shows that EG in summer reaches a maximum of 4.2 MJm−2h−1 and in the rainy season it reaches a minimum of 3.7 MJm−2h−1, both at noon, and in summer the EDFh is 35% of the EGh and it is 46% in the rainy season