the safety of hydrogen generation facilities is the main concern in their process operation. this study was conducted to identify the hazards and evaluate the risks of a hydrogen generation plant. for this purpose, prha (process hazard analysis) was applied for hazard identification while lopa (layer of protection analysis) was used for risk assessment. the study was conducted in the hydrogen p...

clean hydrogen is the major energy carrier for power production. the conversion of co to co2 and zero emission during hydrogen energy production causes high capital cost. it is a matter of prestige to optimize the process in order to make zero emission and cost effective production of clean hydrogen energy and electric power. in this era, coal gasification is the most promising technology for t...

importance of sediment storage has been expressed as being higher than that of water in floodwater spreading networks. to determine the contribution of each geological formation in sediment input of gachsaran floodwater spreading station after 12 years of flood spreading, sediment sampling was conducted in 16 points and 0-15 cm depth of the field. using dry sieve analysis, all samples were anal...

pond aquaculture is the most significant fish production method in central europe, approximately 70% of the total fish production is originated from traditional fish ponds in this region, which is a resource-saving, ecologically sustainable production method. however, the growth of this sector is not expected because of the low production capacity of valuable fish species and the relatively hig...

Many studies have examined the role of mean climate change in agriculture, but an understanding of the influence of inter-annual climate variations on crop yields in different regions remains elusive. We use detailed crop statistics time series for ~13,500 political units to examine how recent climate variability led to variations in maize, rice, wheat and soybean crop yields worldwide. While s...

this article will address the extension of super efficiency method to rank the non-extreme efficient decision making units. many methodologies have introduced methods that can rank efficient units, amongst which, the super efficiency method due to its ability to provide meaningful geometrical as well as economic analyses has a significant place. but the common problem with all the super efficie...

Several studies have shown that global crop production needs to double by 2050 to meet the projected demands from rising population, diet shifts, and increasing biofuels consumption. Boosting crop yields to meet these rising demands, rather than clearing more land for agriculture has been highlighted as a preferred solution to meet this goal. However, we first need to understand how crop yields...