Classical trajectory Monte Carlo model calculations for the antiproton-induced ionization of atomic hydrogen at low impact energy

The three-body dynamics of the ionization of the atomic hydrogen by 30 keV antiproton impact has been investigated by calculation of fully differential cross sections (FDCS) using the classical trajectory Monte Carlo (CTMC) method. The results of the calculations are compared with the predictions of quantum mechanical descriptions: The semi-classical time-dependent close-coupling theory, the fully quantal, time-independent close-coupling theory, and the continuum-distorted-wave-eikonal-initial-state model. In the analysis particular emphasis was put on the role of the nucleus-nucleus (NN) interaction played in the ionization process. For low-energy electron ejection CTMC predicts a large NN interaction effect on FDCS, in agreement with the quantum mechanical descriptions. By examining individual particle trajectories it was found that the relative motion between the electron and the nuclei is coupled very weakly with that between the nuclei, consequently the two motions can be treated independently. A simple procedure is presented by which the NN interaction effect can be included into the calculations carried out without it.Comment: 8 pages, 6 figure

Free evolution of an incoherent mixture of states: a quantum mechanical approach to the van Cittert-Zernike theorem

We study the time evolution of an incoherent mixture of quantum states and demonstrate, in very simple terms, a quantum mechanical equivalent of van Cittert–Zernike theorem, which can be easily explained to Quantum Physics students with a basic knowledge of the density matrix theory. Finally, we exemplify this result by applying it to the quantitative analysis of the coherence of a beam of particles in atomic collisions.Fil: Fabre, Ignacio. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Navarrete, Francisco Oscar. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sarkadi, L.. Hungarian Academy of Sciences; HungríaFil: Barrachina Tejada, Raul Oscar. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

EXTRACTION AND ISOLATION OF PROTEIN FROM LUPINE (Lupinus termis L.) SEEDS

Extraction and isolation of protein from lupine seeds by using distilled water, salt solution, and alkaline solution and precipitation with 0.1 N hydrochloric acid at pH 4.00, followed by centrifugation and freeze drying was studied. Extraction with water yielded 28.5%, with 5% sodium chloride solution 43.5% and with 0.1 N sodium hydroxide solution 79.7% protein. Alkaline solution was found most satisfactory for maximal extraction of protein from lupine seeds. The effect of various factors on the protein extraction, concentration of extractant, time of extraction and relative amount of solvent to dry seeds were also investigated. The digestibility of isolated protein - measured with in vitro enzymatic method - was high (90%)

Calculation of the matrix elements of the Coulomb interaction involving relativistic hydrogenic wave functions

Abstract A program is presented for calculation of the matrix elements of the Coulomb interaction between a charged particle and an atomic electron, ψ † f (r)|R − r| −1 ψ i (r) dr. Bound-free transitions are considered. Relativistic hydrogenic wave functions are used for the numerical evaluation of the matrix elements. The applied algorithm is based on the multipole series expansion of the Coulomb potential. The radial part of the terms of this series expansion (known as G functions) can also be obtained. Nature of physical problem The theoretical description of the excitation and ionization of atoms by charged particle impact often requires the knowledge of the matrix elements of the Coulomb interaction. The program MTRD-COUL calculates the matrix elements between bound and free states represented by relativistic hydrogenic wave functions. Method of solution The multipole series expansion of the Coulomb potential is used to solve the problem. Restrictions on the complexity of the problem The matrix elements are calculated with the following restrictions. The initial bound states are limited to 1s 1/2 , 2s 1/2 , 2p 1/2 , 2p 3/2 , 3s 1/2 , 3p 1/2 , 3p 3/2 , 3d 3/2 , 3d 5/2 . The quantum number l in the final state has a maximum value of 10. Typical running time The test run requires about 170 s

EFFECT OF FERTILIZERS ON THE YIELD, PROTEIN CONTENT AND AMINO ACID COMPOSITION OF WINTER CEREALS

The effect of different fertilizers (nitrogen, phosphorus, potassium) and their combinations on the yield, raw protein content and amino acid composition were studied in field experiments. The levels of treatment were 200 kg/ha for nitrogen, 500-1000 kg/ha for phosphorus and potassium. Winter rye, triticale and wheat cultivar were grown in two subsequent years. Nitrogen fertilization in all cases increased the yield of grains and the raw protein content. The increase reached about 50% in average comparing with control samples grown without adding nitrogen fertilizers. Although there are significant differences between the different cereals studied, it can be generally stated that the increase in protein content is connected with a decrease in the essential to non-essential amino acid ratio. The decrease is higher if only nitrogen fertilizer is used and moderate if a combined treatment with nitrogen, phosphorus and potassium fertilizer is applied

INVESTIGATION OF SOME FUNCTIONAL AND NUTRITIVE PROPERTIES OF CEREAL GERM PROTEINS

Proteins, protein concentrates and isolates were prepared frolll wheat, rye, barley, rice and maize germs. after defatting with hexane or supercritical carbon dioxide, by alkaline extraction (NaOH, pH=10) and acid precipitation (0.1 mol/l HCI). The chemical composition, amino acid composition and functional properties (emulsifying properties, foam activity and stability, water , and oil absorption, solubility) were determined. The digestibility and biological value of protein preparations were also calculated. Protein isolates had a high protein content (75.8 - 94.3%). The oil content was low, except in maize germ protein isolates, obtained after defatting with supercritical carbon dioxide. High digestibility (83 - 90%) and moderate biological value (63 - 7,5 FAO/WHO index) was characteristic of all isolates. Methionine and cysteine were the limiting amino acids. Ivlaize germ protein isolates showed the best functional properties, being comparable with those of soy protein isolates. Other germ protein isolates also had acceptable properties. No significant. differences were observed bet ween the functional properties of isolates prepared after defatting with hexane or supercritical carbon dioxide, except the foaming properties. The latter were adversely affected by supercritical fluid extraction