New, Highly Accurate Propagator for the Linear and Nonlinear Schr\"odinger Equation

A propagation method for the time dependent Schr\"odinger equation was studied leading to a general scheme of solving ode type equations. Standard space discretization of time-dependent pde's usually results in system of ode's of the form u_t -Gu = s where G is a operator (matrix) and u is a time-dependent solution vector. Highly accurate methods, based on polynomial approximation of a modified exponential evolution operator, had been developed already for this type of problems where G is a linear, time independent matrix and s is a constant vector. In this paper we will describe a new algorithm for the more general case where s is a time-dependent r.h.s vector. An iterative version of the new algorithm can be applied to the general case where G depends on t or u. Numerical results for Schr\"odinger equation with time-dependent potential and to non-linear Schr\"odinger equation will be presented.Comment: 14 page

Qualidade de biscoitos formulados com diferentes teores de farinha de casca de pequi.

O objetivo deste estudo foi avaliar a qualidade de biscoitos tipo cookie, formulados com diferentes níveis de farinha de casca de pequi (FCP), em substituição à farinha de trigo (FT). Utilizou-se um delineamento inteiramente casualizado, com controle mais quatro tratamentos (12,5%; 25%; 37,5%; e 50% de substituição de FT por FCP), e quatro repetições. Foram analisados: aceitabilidade, cor (luminosidade), composição centesimal, valor energético e teores de alguns minerais de cada amostra

Fluidity of Aluminium Foundry Alloys: Development of a Testing Procedure

The aim of this work is the study and the development of a specifi c testing methodology for evaluating thefl uidity of aluminium foundry alloys. This method, based on the Archimedean spiral, is intended to be easily andpractically used in foundry. The necessary device to perform the tests is made by sand moulds and it reproducesthe Archimedean spiral cavity where the molten alloy is poured. An A356 alloy has been used and a series of testshas been carried out with the purpose to make the methodology operative according to a standardized operatingsequence. The focus has been the maximum repeatability of the results. Fluidity tests, carried out at differentmolten metal temperature, have been performed both on the laboratory scale and within a foundry plant, andthey have concerned either the EN standard alloy and the grain refi ned and Sr-modifi ed one. Finally, a specifi cexperimental test has been numerically studied by means of a commercial process simulation software. Theobtained results suggest to increase appropriately the initial temperature of the bath to improve the repeatabilityof the experiments. Furthermore, thin section of the spiral cavity induces high cooling rates able to prevail over theeffects of preliminary treatments of the molten bath

Diagnóstico da cultura da melancia em Roraima.

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Functional, thermal, and pasting properties of cooked carioca bean (Phaseolus vulgaris L.) flours.

This study verified if cooking presoaked beans in the steam of autoclave improves the pasting properties, texture profile, water-solubility (WSI), emulsifying capacities of aged carioca bean' flours. The carioca beans flour presented high content of protein (20.7 -22.3 g.100g -1), resistant starch (RS) (8.3 - 31.1 g.100g -1), and dietary fiber (TDF) (18.9 - 23.7 g. 100g -1), and the cultivar Notavel presented the highest content of total dietary fiber and resistant starch for both cooked and raw flour. The pretreatment promoted an increase in TDF (8.8 %, cultivar Dama) and a decrease in RS (19.5 %, 33.4 %, and 47.0 % for cultivars Imperador, Gol, and Bola Cheia, respectively). Regarding the pasting properties, the heating process promoted a reduction in the values of peak viscosity, final viscosity, breakdown, and setback for all carioca bean cultivars. The other parameters, i.e., gel hardness, WSI, emulsifying capacity, and stability also presented a significant decrease in the cooked flours. So, the pretreatment promoted a total or/partially starch pre-gelatinization and the denaturation of the proteins of the flours which might increase their acceptability for food development.Available online 6 December 2021