ammonia in air can be hazardous to human and animal life and should be removed from the environment. recently the removal of environmental pollutants such as ammonia by means of natural and modified zeolites has attracted a lot of attention and interests. in this study the capability of three iranian natural zeolites (clinoptilolite) in point of view of removal of ammonia from air was investiga...

introduction: this study was carried out to compare the effect of different suture removal time on surgical wound healing. materials and methods: twenty-one male albino rabbits were used. under general and local anesthesia a moucoperiosteal rectangular flap was raised in each animal and then repositioned and sutured. the animals were randomly divided into three experimental groups of seven anim...

conclusions the results of this study show that it is possible to remove nitrate, and its intermediates from waste water. regarding the desirability of the process, the field scale study is proposed. results the results showed that by applying electric current of 0.14 a for 120 minutes, the nitrate content would reduce down to 97%. the obtained r2 for the nitrate removal model was higher than 0...

Environmental context Understanding mercury transformations in the aquatic environment is of utmost importance for improvement biogeochemical modelling and sound environmental risk assessment. In such a context, we discuss critically advancement knowledge on role phytoplankton (algae cyanobacteria) cycling environment. Important research advances revealed that different microalgal species cyano...

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...