Early Age Sealing Capacity of Structural Mortar with Integral Crystalline Waterproofing Admixture

Crystalline admixtures embedded in concrete may react in the presence of water and generate thin crystals able to fill pores, capillaries and micro-cracks. Once the concrete has dried, the crystalline chemicals sit dormant until another dose of water starts the crystallization again. The research aims to analyses the early age self-sealing effect of a crystalline admixture at a dosage rate of 1–3% of the cement mass. Specimens made with two types of gravel were pre-loaded with three-point bending to up to 90% of the ultimate capacity, and conditioned through wet–dry cycles. Micro-crack closure was measured with a microscope after pre-loading, and after 1 day, 4 days, 8 days, 14 days and 20 days of wet–dry exposure. The results show that an admixture content of 3% achieves the best early self-sealing performance. These results are also confirmed by probabilistic analyses, which also emphasize the self-sealing potential of lower ICW contents.

Application of Cationic Tapioca to Unmodified Pearl Corn Starch – A Papermaking Handsheet Study

An handsheet study was performed to compare the application of unmodified pearl corn starch and cationic tapioca starch on 100% recycled paperboard. To analyze the benefits tensile index, Canadian Standard Freeness, and starch retention was measured. The results found that cationic tapioca starch had the highest tensile index at 61.36 N*m/g for a dosage rate of 16 lbs./ton at a comparable dosage for unmodified pearl corn starch at 48 lbs./ton the tensile index was 56.11 N*m/g. Tests of the Canadian Standard Freeness showed that the unmodified pearl corn starch had the lowest freeness at 34.3 ml. The cationic tapioca starch had a freeness of 53.5 ml. For starch retention, more starch was retained in the sheet with cationic tapioca starch, with only 0.0065 grams ending up in the filtrate, compared to 0.015 grams of filtrate for the sheet containing unmodified pearl corn starch.

Ethnomedicinal knowledge for treating stomachache among the Bagata tribe of Visakhapatnam District (Andhra Pradesh)

The paper examines traditional uses of some plants used to treat stomachache by the Bagata tribe of Visakhapatnam district. Forests have provided enough material to tribes for use in the traditional medicine. During the survey of the tribal villages, data on 47 medicinal plants used to cure stomachache were collected. Forty-seven plant species belongs to 45 genera and 30 families are reported along with family, vernacular and English names, dosage rate and mode of administration have been enumerated.