ABSTRACT Direct atmospheric 14 CO 2 measurements began in New Zealand 1954, initially to improve C as a dating tool, but quickly evolving into method for understanding the carbon cycle. These early immediately demonstrated existence of an “Atom Bomb Effect,” well “Industrial Effect.” two gigantic tracer experiments have been utilized via over years produce wealth knowledge multiple research fie...

background: thymus daenensis is on e of the endemic aromatic species in iran that its essential oil is used in food and pharmaceutical industries. objective: in this study, the effects of plant growth stages and distillation methods on essential oil content and thymol percentage of this species were evaluated. methods: the aerial parts of th. daenensis were collected in three stages of plant gr...

The reaction of CH₃NH₂ with O₂ on the singlet potential energy surfaces (PES) was carried out using the B3LYP, CCSD(T) and G3B3 theoretical approaches along with 6-311++G(3df,3pd) basis set. The suggested mechanism for the title reaction consists of one pre-reactive complex. From the pre-reactive complex, nine types of products, CH2NH+H2O2, CH3NH+OOH,...

fouling is one of the main parameters in design of any exchanger. ignoring this parameter causes problems such as overheating or under- heating of process streams. in this article a heat exchanger network was designed using process streams data in cdu of tehran refinery. then using tema fouling factors, network exchangers were designed and area and cost were estimated. by changing fouling facto...