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...

Item Parameter Drift occurs over time for various reasons; when test items lose their initial characteristics, such as difficulty and discrimination parameters. Including cases of item parameter drift are revealed, excessive repetition, changes in the education system, and the position of items and the parameters of poor initialization. Item parameter drift causes of the invariance to be violat...

چکیده در این پژوهش، رابطه بین سبک های مقابله ای با جرأت ورزی و پرخاشگری در دانشجویان دانشگاه بین المللی امام خمینی (ره) بررسی شد. نمونه مورد بررسی، شامل 200 نفر (121 زن و 79 مرد) از دانشجویان دانشگاه مورد نظر در دو جنس است که از طریق روش نمونه گیری خوشه ای تصادفی، انتخاب و به پرسشنامه های الگوهای پاسخ دهی بین فردی تونند و پرسشنامه سبک های مقابله ای اندلر و پارکر پاسخ دادند. همچنین از روش های ...

nowadays in trade and economic issues, prediction is proposed as the most important branch of science. existence of effective variables, caused various sectors of the economic and business executives to prefer having mechanisms which can be used in their decisions. in recent years, several advances have led to various challenges in the science of forecasting. economical managers in various fi...

this study investigates the problem of translating religious allusions in persian literature, namely the ones borrowed from quranic verses and hadiths. the purpose of this study is to shed light on how different translators dealt with such a task and also to provide guidelines for translators in coping with religious allusions.

anxiety is one common disorder during childhood. in curing anxiety disorders, there are different types of psychological remedies, pharmotherapy, family therapy, and music therapy that can improve the individual’s anxiety, but we need some other remedies to improve social and emotional relationship and interactions. considering the importance of curing the anxiety disorders, the effect of sand ...

increasing academic and professional language demands around the world are not a deniable fact. the purpose of this study was to investigate english language needs and communication needs of the chemistry students at master and ph.d. levels at the iranian universities. in this research, different methods were used including un-structured interview, structured interview, and two sets of question...

abstract this study is carried out to determine the chemical composition in the three vegetative stages of the haloxylon sp., degradation parameters, with adding naoh and ca(oh2 ). for this purpose, in may and october and january 2010 enough some haloxylon sp. of the ammary area was prepared. crude protein and ash percentage are decrease, neutral detergent fiber percentage with pragress stage ...

the main objective in sampling is to select a sample from a population in order to estimate some unknown population parameter, usually a total or a mean of some interesting variable. a simple way to take a sample of size n is to let all the possible samples have the same probability of being selected. this is called simple random sampling and then all units have the same probability of being ch...