the aim of this paper is eliminating cr(vi) by natural hap. hap is a inexpensive material which is used from bovine critical bone ash in order to remove heavy metal ions like cr(vi). some experiments in different ph are performed (ph=2,3,7). maximum adsorption was appeared at ph=2, dosage=0.3 gr, c0=10 mg/l. cr(vi) removal depends on ph value and initial amount of cr(vi) result of experiments w...

abstract target-oriented approaches to translation studies are regarded as recent theories of translation. one of the most famous theories among these approaches is descriptive translation studies presented by toury (1995). this theory gives a new dimension to translation studies and gives importance to the descriptive rather than prescriptive studies. it also identifies three sets of transla...

this thesis is presented 10 ghz voltage controlled ring oscillator for high speed application. the voltage controlled ring oscillator was designed and fabricated in 0.13یm cmos technology. the oscillator is 7-stages ring oscillator with one inverter replaced by nand-gate for shutting down in the ring oscillator during idle mode. tri-state inverter was used to control of 126 bit vector in ri...

Background and objectives: Because of problems dealing with bioremediation including being time consuming, low efficiency and toxicity to biota, application of advanced oxidation processes with higher efficiency and shorter remediation time have been considered for removal of hydrophobic hydrocarbons from contaminated soils. A great interest has been directed to Fenton oxidation because of its ...

Background and Objective: The presence of natural organic materials (NOM) in water resources affects its quality (i.e. color, odor, and taste). In addition, it leads to the fouling of filters and membranes and reduces water treatment efficiency during flocculation/ coagulation. Moreover, NOM reacts with disinfectants and produces byproducts (DBPs), which are harmful to human health. Magnetic na...

abstract this mixed method study examines whether there is any relationship among the variables of the study (job satisfaction, social capital and motivation). the researcher considered job satisfaction and social capital as independent variables; motivation is the dependent variable of the study. the researcher applied a questionnaire to assess each variable. to measure efl teachers’ job sati...

Background and purpose: Cyanide (CN-) is of dangerous pollutants in the environment from industries such as electroplating, mining and paint entering into environment. The present study aimed to review the efficiency of cyanide removal by zirconia photocatalytic process with and without hydrogen peroxide (H2O2). Materials and methods: This was an applied-fundamental study and was conducted in ...

Introduction: In many studies, nanoparticles was used to remediation of heavy metals from water, results of these study showed that these materials have high power in contaminant remediation from aqueous solutions, and bio-absorbents also have high power in water infiltration. The main purpose of this paper is investigation of effects of adding of iron oxides nanoparticles to chrome removal bio...