The specific FTA-ABS and TPI tests are too costly and time-consuming to be used as screening procedures for treponemal disease. The VDRL test detects reagin, the antibody amongst others produced in syphilis and yaws and also present in a wide variety of disorders giving the biological false positive reaction. The RPR card test (Portnoy, Garson, and Smith, 1957; Reed, 1965), like the VDRL test, ...

Pollutants in dye wastewater significantly vary due to the large number of dyes and other chemical compounds used in dyeing processes. The major compounds in dye wastewater are desizing and scouring agents, bleaches, reducing agents, detergents and wetting agents, finishing agents, organic acids and dyes, and fluorescent brighteners1). Physical, chemical and biological methods have been applied...

Microalgae that can grow fast and convert solar energy into chemical energy efficiently are being considered as a promising feedstock of renewable biofuel. Mass production of microalgal oil faces a number of technical barriers that make the current production of biodiesel economically unfeasible. Small size (≈1-20 μm) and negatively charged surface of the microalgal cells pose difficulties in t...

Potential release of soil colloids into groundwater has attracted considerable attention because of their association with heavy metals. Much effort has been focused on using colloid-depositionbased parameters (batch experiment) to predict colloid release in soils (column experiment), though they are two separate processes. In this paper, relative colloid stability ratio was estimated and used ...

Concentrating algal cells by flocculation as a prelude to centrifugation could significantly reduce the energy and cost of harvesting the algae. However, how variation in phenotypic traits such as cell surface features, cell size and motility alter the efficiency of metal cation and pH-induced flocculation is not well understood. Our results demonstrate that both wild-type and cell wall-deficie...

Flocculation onset, the time during the fermentative cycle at which the strains of Saccharomyces cerevisiae become flocculent, is an important factor in the brewing industry. The flocculation ability of Flo 1 phenotype (strain NCYC 869) remained practically unchanged throughout the growth and seems to be insensitive to the presence of nutrients of the culture medium. On the contrary, the floccu...

Two methods, centrifugation and flocculation, were evaluated to determine their efficiencies of recovery of Toxoplasma gondii oocysts from contaminated water samples. Demineralized and tap water replicates were inoculated with high numbers of sporulated or unsporulated T. gondii oocysts (1 x 10(5) and 1 x 10(4) oocysts). The strain, age, and concentration of the seeded oocysts were recorded. Oo...

Flocculation is a key unit operation in domestic and industrial water treatment, beneficiation of minerals, dewatering of sludges and in many industrial solid-liquid separation processes. Coagulants and flocculants are commonly employed as additives to induce aggregation and improve subsequent filtration or dewatering operations. The characteristics of these additives have a strong influence on...

The progressive reduction of velocitygradient to keep the flocculation rate as high as possible without breakage of flocsis called 'tapered flocculation'. In the present work, an attempt has been made to compare the performance of continuous tapered flocculationin conicaland cylindricaltanks. The efficiencyof conical flocculator was found to be higher than that of cylindrical flocculator, espec...

estuaries are considered as highly dynamic ecosystem that include the mixing or transition zone between river freshwater and saline water from oceans and seas. estuaries are very important aquatic systems by preserving the coastal biota. flocculation of metals during mixing of freshwater with saline water can be considered as the most important estuarine processes. due to flocculation process, ...