background and objectives: kefiran (kef) is a water-soluble polysaccharide that can form transparent film however, it is brittle. therefore, in order to improve the mechanical properties of kefiran film, a mixture with other polymers can be offered. the expansion of mixed systems can propose kefiran and polyvinyl alcohol (pvoh) as a new composite film. materials and methods: solutions of 20 gra...

Waterborne polymers, including waterborne polyurethanes (WPU), polyester dispersions (PED), and polyacrylate emulsions (PAE), are employed as environmentally friendly water-based coatings and adhesives. An efficient, fast, stable, and safe cross-linking strategy is always desirable to impart waterborne polymers with improved mechanical properties and water/solvent/thermal and abrasion resistanc...

this research paper presents the use of wasteful supplementary cementitious materials like fly ash and silica fume to conserve the cement used in concrete. the cement industry is one of the major producers of greenhouse gases and an energy user. in this study, portland cement was used as a basic cementitious material. fly ash and silica fume were used as the cement replacements by weight. the r...

Granite is a typical crystalline material, often used as a building material, but also a candidate host rock for the repository of high-level radioactive waste. The petrographic texture-including mineral constituents, grain shape, size, and distribution-controls the fracture initiation, propagation, and coalescence within granitic rocks. In this paper, experimental laboratory tests and numerica...

in this research, the possibility of using high percentage of lignocellulosic fibers in making natural fiber-thermoplastic composite was studied. three weight percentages of bagasse flour namely 40, 55 and 70 percents were chosen. mapp was used as coupling agent at two weight percentages of pp, namely 0, 4 and 6 percents. tensile strength was measured applying instron 6025. the results showed t...

Various studies have reported a significant reduction in tensile bond strength of brackets when bonding is carried out immediately after bleaching. The purpose of this investigation was to determine the effect of an antioxidant agent on the tensile bond strength values of metal brackets bonded with composite resin to human enamel after bleaching with carbamide peroxide (CP). A total of 80 extra...

This study focuses on the effect of the amount of silica fume addition and volume fraction of steel fiber on the engineering properties of cementitious materials. Test variables include dosage of silica fume (5% and 10%), water/cement ratio (0.35 and 0.55) and steel fiber dosage (0.5%, 1.0% and 2.0%). The experimental results included: compressive strength, direct tensile strength, splitting te...

N-methylol compounds, such as dimethyloldihydroxyethyleneurea (DMDHEU), are the most commonly used durable press finishing agents for cotton fabrics by the industry. In this research, we have examined the effects of the catalyst systems used for DMDHEU on the mechanical strength of the crosslinked cotton fabric. The catalysts induce degradation of cellulose as indicated by the decrease in the t...

The tensile strength of water increases when solid particles are filtered out, and it becomes greater the smaller the remaining particles are. Natural particles are of random shape, making parametric studies on the relationship between tensile strength and particle characteristics difficult. In this investigation, using degased tap water from which natural particles larger than about 1 (m were ...