RESUMEN
Prosopis Chinensis represents one of the most suited fiber sources for the production of a wide range of high quality papers and high-purity dissolving pulps. The optimization of kraft pulping covering both continuous and batch processes demands kinetic models suitable for advanced control and offline optimization of the cooking operation. Quite recently, an improved kinetic model structure for softwood kraft cooking has been published, which considers varying alkali and temperature profiles during the cooking [1]. Unfortunately, most alkaline cooking models are based solely on softwood [2, 3]. This work contributes to an improved kinetic model for kraft cooking of Prosopis, suitable for advanced control of modern displacement cooking processes such as the continuous batch cooking process (CBC). After impregnation where the initial lignin has been removed, the bulk and residual delignification have been studied in a batch reactor as a function of the [OH-], [HS-], ionic strength, [Na+], and temperature. The underlying kinetic expressions are similar to those used in the Andersson model also including a mechanism for determining kraft pulping of Prosopis chinensis,the distribution of lignin and carbohydrate species 2 and 3 as a function of the cooking conditions. The kinetic equations were successfully validated against experimental data from a pilot plant digester applying conventional batch cooks. Furthermore, the formation of hexenuronic acid bound to the xylan backbone and its degradation / dissolution were described by a consecutive first-order reaction. In agreement to other studies, the temperature and the effective alkali charge revealed a strong influence on the hexenuronic acid content in the pulp while the effect of sulfidity proved to be insignificant. The role of ionic strength on the HexA content remained unclear. An increase in the ionic strength resulted in a higher maximum HexA content shifted to a higher kappa number (about 58), but with progressive delignification to a kappa number typical for unbleached Prosopis Chinensis, kraft pulp (about 15), the HexA content decreased to a level more than 20% lower as compared to pulps cooked at lower ionic strength.
RESUMEN
Investigation was carried out on Lantana Camara & Prosopis Chinensis, the plants of verbenacea ( vervain) & leguminosae (Mimosaceae) family for studying their chemical constituents by isolation of milled wood lignin of Lantana Camara & Prosopis Chinensis through different isolation techniques such as hydrolysis & solvent extractions.This has indicated that the lignin prepared from wood species Lantana Camara contains carbon 56. 2%, hydrogen 5.80% ,oxygen 36.00% and methoxy groups 19.70%. Prosopis Chinensis contains carbon 60.70%, hydrogen 6.30%, oxygen 33.00% and methoxy groups 19.78%. The C9 formula weight for Prosopis Chinensis & Lantana Camara is 204.82 & 212.99 respectively. The other reactive groups of lignin of Lantana Camara & Prosopis Chinensis investigated were also comparable with the other non wood species.
RESUMEN
A total of 44 cases comprising hypertensive (31) and normotensive group (13) were studied. Serum total calcium concentrations remained unaltered in hypertensives. Platelet cytosolic calcium in hypertensive group was significantly higher as compared to the normotensive controls. Platelet cytosolic calcium correlated with systolic and diastolic blood pressure and mean arterial pressure significantly.
Asunto(s)
Plaquetas/análisis , Calcio/sangre , Humanos , Hipertensión/sangreRESUMEN
Proven cases (28) of glomerulonephritis (GN) were evaluated for clinico-biochemical profile, bleeding time, platelet count, platelet aggregation and platelet serotonergic mechanisms. Inordinate increase in platelet aggregation and altered platelet serotonergic mechanisms (reduced 5-HT, uptake, reduced intraplatelet 5-HT and increased plasma 5-HT) were demonstrated in some histopathological types of GN. The mechanisms and importance of these alterations have been discussed.