Different Levels Of Moisture Content Research Articles

Effect of the Mode of Super Disintegrate Incorporation on Dissolution in Wet Granulated Tablets

The effect of the mode of super disintegrant incorporation in wet granulated tablets was investigated with three super disintegrants: sodium starch glycolate, crospovidone, and croscarmellose sodium. The disintegrants were incorporated extragranularly or intragranuiarly or distributed equally between the two phases. Lactose, naproxen, or dibasic calcium phosphate was used as the principal tablet component to provide various degrees of solubility to the formulations. The formulations were dried to three different levels of moisture content. The results indicated that, for the formulations studied, extragranular incorporation resulted in faster dissolution than did equal distribution intragranuiarly and extragranularly, which in turn was superior to intragranular incorporation. Granulation moisture content was found to have a formulation- specific impact on tablet dissolution, with each main tablet component behaving in a different fashion. When all other factors were kept constant, there was a tendency for croscarmellose sodium to produce faster tablet dissolution than sodium starch glycolate or crospovidone. The super disintegrants tended to promote faster dissolution in a neutral pH medium than in an acidic medium.

The Selective Inactivation of Seed-Borne Soybean Mosaic Virus by Exposure to Microwaves

Soybean (Amsoy 71) seeds infected with soybean mosaic virus (SMV) were treated by exposure to 675 W of microwave power at 2450 MHz for varying times and at two different levels of moisture content....

Crack Formation in Corn Kernels Subject to Impact

ABSTRACT THE formation of internal cracks in corn kernels due to impact loading was investigated for three different levels of moisture content, impact velocity and orienta-tion. The percentage of kernels internally cracked in-creased with an increase in velocity and a decrease in moisture. Side and corner orientations of impact were found to produce the most internal cracks in corn kernels. Analysis of variance studies are discussed.

Micromechanical fracture analysis of amylose

Amylose films were prepared with two distinctly different microstructures, and these specimens were subsequently tensile-tested at different levels of moisture content. Measurement of the strain energy release rate, G l , was approached from three separate methods. Two of these methods, the J integral and stress intensity analyses, are based on bulk tensile properties. The third method involves direct calculation of the work expended in producing the microplastic zone at the crack tip. Birefringence measurements were used in mapping the magnitude and shape of the plastic zones. Although the semicrystalline material would not lend itself to the bulk tensile analyses, G l values were obtained via the optical analysis. For disordered amylose, G l values derived from this optical analysis were found to correlate with those obtained from bulk measurements, and the fracture toughness was found to be comparable to that of other engineering polymers. Surprisingly, moisture content within the range investigated herein has no great effect on the strain energy release rate. This insensitivity is attributed to active interaction between the absorbed water and amylose macromolecules.

Estudos sôbre a conservação de sementes. IV - Café

Sementes de café, recém-colhidas e imediatamente sêcas à sombra e ao sol, foram conservadas com diferentes teores de umidade em dois tipos de recipientes, abertos e hermèticamente fechados, à temperatura não controlada do laboratório. Pelos resultados obtidos através de determinações periódicas das porcentagens de germinação e umidade das sementes armazenadas nessas condições, foram tiradas as seguintes conclusões: a) a vitalidade das sementes foi inteiramente independente do processo de seca; b) a longevidade das sementes conservadas em recipientes hermèticamente fechados foi inversamente proporcional ao seu teor de umidade; sementes com aproximadamente 20%, 13% e 10% de umidade premaneceram viáveis durante 4, 8 e 21 meses, respectivamente. c) o teor inicial de umidade não teve qualquer influência sôbre a longevidade das sementes armazenadas em recipientes abertos; isto se verificou, provavelmente, em virtude da quantidade relativamente pequena de sementes, o que permitiu uma rápida desidratação daquelas que se encontravam com teores elevados de umidade; a vitalidade das sementes colocadas nestes recipientes permaneceu inalterada por oito a dez meses. Estas conclusões estão inteiramente em desacôrdo com as de vários autores, segundo as quais a semente de café perde rapidamente sua vitalidade pela simples desidratação ao ar.