Thermal neutron extrapolation distances for slabs of beryllium and water

Abstract

Extrapolation distances for thermal neutrons have been obtained for slabs of beryllium and light water by minimising the difference between the steady-state leakage spectra calculated on the basis of diffusion and transport theories. Using the present values of extrapolation distance ensure that neutron spectra (both in beryllium and water) calculated on the basis of diffusion theory agree well with the corresponding transport theory spectra, even at distances close to the free surface. The authors find the extrapolation distance to be dependent of the thickness of the slab, increasing with increase in the thickness.

Análise Do Processo De Pirólise De Sementes De Açaí (Euterpe Oleracea, Mart): Influência Da Temperatura No Rendimento Dos Produtos De Reação E Nas Propriedades Físico-Químicas Do Bio-Óleo / Process Analysis of Pyrolise of Açaí (Euterpe Oleracea, Mart) Seeds: Influence of Temperature on the Yield of Reaction Products and Physico-Chemical Properties of Bio-Oil

“…O rendimento do bio-óleo de 4,39% (em peso) é inferior aos dados semelhantes para o rendimento sem óleo de umidade obtido por pirólise rápida de resíduos florestais [18][19]69], bem como resíduos agrícolas relatados na literatura [38-39, 48, 52, 57-58], variando de 10 a 25% (em peso), dependendo da composição centesimal/elementar da matériaprima. O baixo rendimento de bio-óleo deve-se provavelmente ao alto teor de fibras, conforme ilustrado na Tabela 1.…”

“…A caracterização centesimal de sementes de Açaí (Euterpe oleracea Mart.) totaliza 97,57% (em peso) em base seca[19], mostrando que a soma (umidade, lipídios, proteínas, fibras, hemiceluloses, celulose, lignina, matéria volátil, carbono fixo e cinza) é quase próximo a 100% (em peso). Caracterização centesimal e elementar de sementes de Açaí (Euterpe oleracea, Mart) em comparação com estudos semelhantes relatados na literatura[9][10][11][12].…”

Effective removal of hexavalent chromium from aqueous solutions by adsorption on mesoporous carbon microspheres

“…What's more it does not generate secondary pollutant during industrial operations. Activated carbons have been widely used for the adsorption of Cr(VI) in terms of their wide availability, developed physical and chemical properties [10,11]. The micropores in activated carbons could physically adsorb Cr(VI) from water via the Van de Waals force.…”

Vibrational spectroscopic analysis of 2-bromobenzoic and anthranilic acids: A combined experimental and theoretical study

“…Verma et al [28] studied infrared absorption spectrum of m-flurobenzoicacid with the help of nujol mull in the region 250-4000 cm −1 . Mohan and Arul Dhass [29] have recorded the Fourier transform infrared and laser Raman spectra of para-chlorobenzoic acid in the regions of 200-4000 and 30-4000 cm −1 , respectively. Swaminathan et al [30] investigated the vibrational spectra of 2-bromobenzoic acid with the harmonic vibrational frequencies calculated at HF and B3LYP level of theories using 6-311++G(d,p) basis set with appropriate scaling factors.…”