Feno e silagem como volumoso para confinamento de bovinos de corte.

bitstream/item/67190/1/CT-49-2001.pd

Monte Carlo studies of the jet activity in Higgs + 2 jet events

Tree-level studies have shown in the past that kinematical correlations between the two jets in Higgs+2-jet events are direct probes of the Higgs couplings, e.g. of their CP nature. In this paper we explore the impact of higher-order corrections on the azimuthal angle correlation of the two leading jets and on the rapidity distribution of extra jets. Our study includes matrix-element and shower MC effects, for the two leading sources of Higgs plus two jet events at the CERN LHC, namely vector-boson and gluon fusion. We show that the discriminating features present in the previous leading-order matrix element studies survive.Comment: 12 pages, 10 figures. Version to appear on JHEP. Figs. 5-8 replaced with colour version

Avaliação de cultivares de trigo de duplo propósito, recomendados para cultivo no estado do Rio Grande do Sul.

bitstream/CNPT-2010/37413/1/Comunicado-137.pd

Some analytic results for two-loop scattering amplitudes

We present analytic results for the finite diagrams contributing to the two-loop eight-point MHV scattering amplitude of planar N=4 SYM. We use a recently proposed representation for the integrand of the amplitude in terms of (momentum) twistors and focus on a restricted kinematics in which the answer depends only on two independent cross-ratios. The theory of motives can be used to vastly simplify the results, which can be expressed as simple combinations of classical polylogarithms.Comment: 18 page

Avaliação de cultivares de trigo de duplo propósito, recomendados para cultivo no estado do Rio Grande do Sul.

bitstream/item/31090/1/Comunicado-137.pd

Resultados da experimentação de genótipos de trigo para aptidão a duplo propósito no Paraná, em 2000.

bitstream/item/84114/1/CNPT-BOL.-PESQ.-6-01.pd

Experimentação de genótipos de trigo para duplo propósito no Paraná, em 1999.

Introdução; Material e métodos; Resultados e discussão; Matéria verde; Matéria seca; Rendimento de grãos; Ciclo e altura; Características agronômicas.bitstream/item/157857/1/FL-07263.pd

Structural, energetic and kinetic database of catalytic reactions: Benzyl alcohol to benzaldehyde oxidation on MnOx clusters

Data here reported are connected with the research article “Benzyl Alcohol to Benzaldehyde Oxidation on MnOx Clusters: Unraveling Atomistic Features” Gueci et al. [1]. This work described and discussed structural and energetic results, calculated by Density Functional Theory (DFT). In order to get kinetic information, DFT results were refined by an original approach, which will be shortly described in the following article. The crossed analysis of experimental and computational energetic and kinetic data allowed to (i) reconstruct the complicated lattice that connects the primary and secondary mechanisms of the reaction and (ii) identify alternative process pathways capable of by-passing parasitic mechanisms, decreasing selectivity. On the other hand, the data here presented show what is the basic information necessary to obtain the modeling of a complex process of heterogeneous catalysis. Moreover, they can be used either to verify the validity of the discussion outlined in the original article Gueci et al. [1] or as a starting point to computationally explore alternative routes and the related kinetics of the same oxidation processes, in the aim to further optimize the corresponding experimental approach

DFT insights into competing mechanisms of guaiacol hydrodeoxygenation on a platinum cluster

In a scenario of declining fossil resources and increasing demand for renewable and sustainable alternatives, biomass is the only source able to offer an easy and gradual transition in the use of current energy technologies based on the exploitation of carbon derivatives. Its conversion to liquid fuels has oriented our study towards the computational mechanistic analysis of the guaiacol catalytic hydrodeoxygenation, which is currently considered one of the most challenging routes for upgrading biomass-derived bio-oils. For this purpose, a subnanometric Pt10 platinum cluster was chosen as the catalyst model, with Pt as a computational reference element for catalytic hydrogenation, and guaiacol as a model compound of bio-oils. DFT calculations revealed that the energy barriers related to the cleavage of C(sp2)-O bonds in the direct deoxygenation mechanism are significantly lower (by an average of 60 kJ mol−1) than those in the deoxygenation-through-hydrogenation mechanism in which C(sp3)-O bond breaking from a saturated ring occurs. Even if the ring hydrogenation is easier in the oxygenated compound, the analysis reveals that the direct deoxygenation mechanism is favoured at all temperatures. Furthermore, the results obtained highlight that, from a thermodynamic perspective, the removal of oxygen groups preferentially occurs by the elimination of the -OCH3 fragment as methanol and then of the -OH fragment as a water molecule

DFT study on zeolites’ intrinsic Brønsted acidity: The case of BEA

Since Brønsted acidity is a crucial aspect for the applications of zeolitic materials in heterogeneous catalysis, great effort was devolved to characterize the number, strength and location of the potentially active acidic sites. Quantum chemical calculations can turn out essential in estimating the intrinsic acidity by computing deprotonation energy (DPE) values, although each method comes with its own difficulties. In this context, three approaches within density functional theory were employed to study the intrinsic acidity of 30 topologically distinct Brønsted sites in the β-zeolite framework. Advantages and disadvantages of the three methods were outlined and the acidity order between the sites was assessed, being the DPE range 59 kJ mol−1 wide, with the proposed best approach. By dividing the range into three portions, the sites were classified as having high, medium and low acidity. Hydrogen bonds formation was found to be a contributing factor in determining a low Brønsted acidity