Solids Liquids Gases/vapours Asbestos dust Sprayed droplets Ammonia Engine exhaust particles Paints Carbon monoxide Lead dust and fume Pesticides Carbon dioxide Silica dust Power coating mix Freon’s Welding fume Liquid jetting Helium Shot blasting dust Sewage water Nitrogen Wood dust Mercury vapour Smoke Mists Solvent vapours Fungal spores Chrome acid Engine exhaust gases Bacteria Cutting fluid...

colloidal nanosilica is currently being produced by various methods which are mainly high energy intensive and/or not environmentally friendly. it is therefore essential to develop new energy-efficient and environmentally friendly technologies. this paper introduces a new ultrasound assisted route based on alkali leaching of silica fume for synthesis of colloidal silica nanoparticles. the ef...

Corrosion of steel is one of the most important potential dangers and threats in concrete structures. Corrosion of steel embedded in reinforced concrete plays a key role in reducing the strength and durability of reinforced concrete. Several studies have proposed that alternative approaches to enhancing the performance of reinforced concrete and its resistance to corrosion. In this study, the r...

the purpose of the present study was to synthesize and characterize nanosilica from alkali-extraction of silica fume under controlled conditions using poly (vinyl alcohol) (pva) as a dispersing agent. the dissolution efficiency of silica fume was affected by various factors such as concentration of the reagent, reaction time and temperature. a maximum dissolution efficiency of 91% was achieved ...

Despite its few inherent shortcomings, concrete has proved to be the most widely used construction material, no substitute in time still to come. In the present investigation, study of admixture of concrete was carried out. The strength of concrete depends on its mix proportions. We used so many admixture e.g. ‘silica. Fumes, fly ash etc , when we used these type of admixture the result was ver...

Nanosilicas have been known as super-pozzolanic materials and compared to silica fume, these materials have higher purity of silica and finer particles. However, in contrast to silica fume, nanosilicas are produced by various methods, leading to different morphologies and agglomeration statuses in their initial form. On the other hand, due to several mechanisms such as the bridging effect of ca...

recent tendencies in concrete technology have been towards to high- performance concrete with a low water-cement ratio. however, high performance concretes have some problems. one of the problems is early-age cracking due to autogenous shrinkage. this study presents the results of an experimental investigation carried out to evaluate the autogenous shrinkage of high-strength concrete. accordin...

This paper presents the results of an experimental investigation carried out to evaluate the shrinkage of High Strength Concrete. High Strength Concrete is made by partially replacement of cement by flyash and silica fume. The shrinkage of High Strength Concrete has been studied using the different types of coarse and fine aggregates i.e. Sandstone and Granite of 12.5 mm size and Yamuna and Bad...