abstract in aggregate, active forms of reactive silica with mineral names are sometimes associated with sand and gravel in concrete mixture. alkali hydroxides originated from alkalis in the cement or other resources form an alkaline silica gel with this reactive silica which becomes swallowed and expanded during time causing damage to concrete. there have been growing researches on alkaline r...

In this research project, the properties and characterization of one kinds of Iranian bauxite extracted from Damavand Shahbolaghi mine near Tehran were compared with one type of industrial China's refractory grade bauxite in order to using in refractory industries. At first physical, chemical and thermal properties and phase and micro structural evolutions of as received and sintered samples at...

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 nowadaysphotovoltaic solar cells (pvs) areacknowledged the fastest growing energy technology in the word, however, they only account for only fraction of current global renewable energy capacity. it isrecognized that this incomplete market penetration has been largely a result of the technology’sexcessive cost. so researchers are trying to find innovative, economic way with theaim of ...

One of the management practices to reduce the harmful effects of chemical fertilizers and to protect soil and water resources is applying a combination of organic and chemical fertilizers that can better than using them separately. Therefore, in order to understand and identify the effectiveness of this management practice, it is necessary to examine runoff and sediment production. This study w...