one of the most important factors in study of project’s , is the study of environmental opportunities factors the permanent study of environmental opportunity factors . the study of permanent environmental changing and knowing golden threats’ cooperate with possible threats and at the result in structure forming and future skeleton of organization has a vital effects . the petrochemical industr...

in civil engineering concrete is a material combined of hydraulic cement, sand, gravel and water. gravel and sand compose 60 to 70 percent of concrete. these aggregates support compression force of concrete. cement paste acts as glue to stick grain together. in bushehr factories producing aggregates do not operate according to astm standards, so that fineness modulus (fm) of the produced sands ...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

attempts have been made to study the thermodynamic behavior of 1,3 butadiene purification columns with the aim of retrofitting those columns to more energy efficient separation schemes. 1,3 butadiene is purified in two columns in series through being separated from methyl acetylene and 1,2 butadiene in the first and second column respectively. comparisons have been made among different therm...

there is no doubt that human being needs to become integrated with industry and industry needs to be progressed, daily. on the other hand, serious events in industrial units specially in oil industries has been shown that such damages and events are industry related ones. the consequence of such events and damages which resulted in chemical and poisoned explosions and loss of life and property ...

abstract nowadays, industries cannot play a crucial role in national and international competitions. the tourism industry is no exception. tourism industry development as the most important economic sector and income generation is one of the key challenges of economic development in the world. therefore, countries were successful that take advantage of the capabilities of tourism sector using ...

this research was conducted in two protect and destroy region in the middle zagros, in illam province. in order to identification of ecological species group and evaluate density of regeneration, effect of many factors such as protection, vegetation, physiographic factors, physical and chemical properties of soil in study locations were studied. to achieve these purpose number of 54 plots using...

building on previous studies on the effectiveness of different types of written corrective feedback, the present study aimed at investigating whether direct focused corrective feedback and direct unfocused corrective feedback produced any differential effects on the accurate use of english articles by efl learners across two different proficiency levels (low and high). in current study, the par...

the aim of the current study was to investigate the relationship among efl learners learning style preferences, use of language learning strategies, and autonomy. a total of 148 male and female learners, between the ages of 18 and 30, majoring in english literature and english translation at islamic azad university, central tehran were randomly selected. a package of three questionnaires was ad...

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...