Étude structurale du composé Cu Cl, CH2CN

The existence of the crystalline compound CuCl.CH₃CN was established. This compound belongs to the space group Pmnb (Z = 4) ; the parameters of the unit cell are : a = 3.90 ± 0.01 Å ; b = 8.58 ± 0.02 Å ; c = 12.93 ± 0.03 Å. A Patterson synthesis led to a rough approximation of the crystal structure. A more precise determination of the positions of atoms was made by means of Fourier series and difference series ; further adjustments of the results were obtained by applying the method of least squares to structure factors of the reciprocal lattice. The structure consists of -Cu-Cl- chains in the direction of the unit vector a. Each Cu atom is surrounded by three Cl atoms and one N atom situated at the vertices of a tetrahedron.On signale l'existence d'un corps cristallisé de formule CuCl, CH₃CN. Il appartient au groupe spatial Pmnb (4 unités formulaires par maille) ; les paramètres de la maille élémentaire sont : a = 3,90 ± 0,01 Å ; b = 8,58 ± 0,02 Å ; c = 12,93 ± 0,03 Å. La position des atomes a été déterminée, en première approximation, par l'étude des projections de Patterson. Ces positions ont été précisées d'après l'examen des séries de Fourier et des séries˗différences, et affinées à l'aide d'un programme de moindres carrés opérant sur l'ensemble des facteurs de structure du réseau réciproque. La structure est constituée de chaînes ... -Cu-Cl- ... s'étendant parallèlement au vecteur a. Chaque atome de cuivre est entouré tétraédriquement par 3 atomes de chlore et un atome d'azote.Massaux Michel, Bernard Maurice J., Le Bihan Marie-Thérèse. Étude structurale du composé Cu Cl, CH2CN. In: Bulletin de la Société française de Minéralogie et de Cristallographie, volume 92, 2, 1969. pp. 118-125

Effect of the sowing date on physicochemical and fonctional properties of native starches extracted from European soft wheat (Triticum aestivum L.)

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High pressure-induced gel formation of chicken meat patties

High pressure treatments produce gelified chicken meat patties with new properties thigh water retention and cohesive texture) and without salt or fat addition. In comparison with heat-induced patties, the pressurised patties present an equivalent hardness with better water binding properties. Pressurisation causes an increase of the colour lightness parameter (L*) and a decrease of redness (a*) and yellowness (b*); but the meat discoloration provoked by the pressure treatments is less significant than the colour changes induced by heating. The pressure-gelation of chicken meat patties is affected by the intensity, the duration and the temperature of the process. The elevation of pressure from 400 to 600 MPa enhances the texture qualities and the water binding capacity of formed gels. A positive effect on texture quality. is observed by prolonging the pressurisation time up to 30 min. The pressurisation temperature (between 15 and 40 degreesC) has no effect on product quality. Addition of salt (fat) prevents (reduces) the gelation ability of meat patties under pressure, whereas it improves the texture of heat-induced gels