conclusions experimental results showed that mcns is an excellent sorbent for removal of mercury ions from petrochemical waste water. in addition, highly complex matrix of this waste does not affect the adsorption capability of mcns. results an effective hg (ii) removal (99.8%) was obtained at ph 6, with 50 mg of mcns for an initial concentration of this ion in petrochemical waste water (5.63 m...

conclusions it was shown that the removal efficiency of nitrate was directly proportional to the amount of chaff, temperature, and contact time but inversely to the ph. this study showed that nitrate removal by chaff is a promising technique. results the result of this study revealed that chaff as an absorbent could remove nitrate from solutions, and the efficiency of adsorption increased as co...

background: as fluoride concentration in drinking water is one of the effective parameters in human health, finding the ways to remove excess amount of fluoride is very important in water supply projects. this study aimed to evaluate mendon bauxite mine in the removal of fluoride from drinking water. methods: this experimental study was conducted from may to october 2013 on synthetic and actual...

in this paper, we present a binary-linear optimization model to prevent the spread of an infectious disease in a community. the model is based on the remotion of some connections in a contact network in order to separate infected nodes from the others. by using this model we nd an exact optimal solution and determine not only the minimum number of deleted links but also their exact positions. ...

this is a case presentation of a 26-year-old woman with a moderate-sized atrial septal secundum defect (17mm) who underwent catheterism, during which an amplatzer septal occluder number 26 was inserted successfully. on the second postoperative day, she deteriorated and a clinical examination showed a typical tamponade. after a percutaneous aspiration of the pericardial cavity and transient impr...

the removal of copper (ii), zinc (ii), and chromium (iii) from wastewater by carrot residues(cr) was investigated to evaluate cation exchange capacity. the effects of solution ph and co- ions werestudied in batch experiments. adsorption equilibria were initially rapidly established, and then decreasedmarkedly after 10 min. column experiments were carried out in a glass column filled with cr toe...

in this study, the performance of electro-coagulation in combination with aluminum sacrificial anode, in removal of zinc and copper has been investigated. several parameters, such as pollutant concentration, ph, electrical potential, cod, turbidity and contact time were studied to achieve a higher removal capacity. variable concentrations (5-50-500 ppm) of zinc and copper solutions were prepare...

hydro-induction sediment discharge technique (hsdt) aims to prevent reservoir sedimentation by withdrawing the discharge water from the reservoir bottom to suck up and discharge sediments, and by inducing vertical vortexes and undercurrents in the reservoir bay to keep sediments agitated and moving. the technique is facilitated with an innovative discharge conduit system having bottom intakes t...

since nox family, one of the most important causes of air pollution, is the primary source of acid rains, ozone layer depletion, and breathing disorders, mitigation of these pollutants is now a global concern. in the off-gases of internal combustion engines running with oxygen excess, non-thermal plasmas (ntps) have an oxidative potential, which results in an effective conversion of no to no2. ...

nanoparticles of manganese-dioxide synthesized by mechano-chemical reaction were used foras(iii) and as(v) sorption from water environment. the influence of a milling time of manganese-dioxide on sorption was examined with batch procedure. sorption as a function of contact time was investigated. kinetic of sorption, for both as(iii) and as(v), was fast. the equilibrium condition for milled sorb...