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...

copper extraction from heap 3 low grade ore at sarchechmeh is limited due to its mixed composition (copper oxide and sulphide minerals). changing this heap to a bioheap could improve the copper recovery.

abstract chickpea is weak in competition of weeds that damages to it at between 40 t0 60 percent. kermanshah province is one of the most important region for chickpea fields in iran. for these reosons, weed management is necessary in this crop. in order to evaluate of herbicides and stubble control on broad leave weeds control in chickpea. experiment was conducted in agricultural research stat...

determination of uranium in natural water and complex solutions using ion exchange chromatography: a combined procedure using ion exchange chromatography and uv-vis spectrophotometry techniques has been developed to measure uranum in natural water and complex solutions. after conditicing , one hundred milli liters of sample solutions have been passed through an ion exchange column,pachked with ...

after the soviet union dissolution, a chaotic period was begun in the russia. russia lost its glory and felt disgrace. the first group of elites came to power under yeltsin; they tried to re-define russia’s identity as a european country and build a foreign policy on this baseline. therefore russia tried to become closer with the west especially with the u.s. according to their view the sovie...

abstract: since sugar consumption is directly related to diabetes and other illnesses such as obesity, the issue that will most heavily dominate the health food market is blood sugar management and low glycemic foods. using calcium chloride and gums such as sodium alginate and low ester pectin as thikener and a high-potency sweetener aspartame we were able to reduce sugar content of sour cherry...

this study examines the effetivenss of task-based activities in helping students learn english language structures for a better communication. initially, a michigan test was administered to the two groups of 52 students majoring in english at the allameh ghotb -e- ravandi university to ensure their homogeneity. the students scores on the grammar part of this test were also regarded as their pre...

abstract the current study set out to address the issue as to whether the implementation of portfolio assessment would give rise to iranian pre-intermediate efl learner autonomy. participants comprised 60 female in pre-intermediate level within the age range of 16-28.they were selected from among 90 language learners based on their scores on language proficiency test -key english test. then, t...

the images of muslims in media, literature and politics have been mostly black and white portrayals of a people alien to modernity, civilization, rationality and pluralism. since the end of the cold war and the onset of deadly terrorist attacks in different areas of the world, especially in the united states, these representations show a palpable difference: muslims are represented not only as ...

in this study, a simple, rapid and selective method was developed for the determination of dexamethasone. the proposed method is based on inhibitory effect of dexamethasone on the oxidation of orange-g by bromate in sulfuric acid media. the reaction was followed spectrophotometrically at 478.5 nm (?max). under optimum experimental conditions, (72.6 ?mol l-1 of orange-g, 0.76 mol l-1 of h2so4, 0...