the major sources of pahs are anthropogenic. these may be generated by pyrolytic and petrogenic processes. low molecular weight pahs come into the aquatic system through the accidentally leakage of oil spills. incomplete combustion at high temperature will release high molecular weight pahs by products of pyrolytic processes. the methods for assigning sources of pahs include paired isomeric rat...

The structural and photoluminescence (PL) properties of thin films of poly(3-hexylthophene) (P3HT) with molecular weights (MWs) of 3000 and 13,300 have been investigated. Although high MW P3HT always self-organizes into one packing structure (form I), low MW P3HT forms two different packing structures (forms I and II) depending on the fabrication conditions. In this work, several fabrication te...

The research about molecular weight and functional group analysis of low liquid cyclic natural rubber has been done. aim this is to achievement the quality rubber. This made in several steps such as preparation sample rubber, process degradation characterization LCNR by using FTIR, GPC viscosity test. Degradation done with help phenylhydrazine reagent oxygen gas atmosphere a flow rate 2 LMin-1 ...

poly(vinyl acetate) is synthesized via solution polymerization, and then it is converted to poly(vinyl alcohol) by alkaline alcoholysis. the aim of the work study was to investigate statistically the  influence of reaction variables in vinyl acetate polymerization, the conversion of this monomer to polymer, degree of branching of acetyl group in poly(vinyl acetate), as well as the molecular wei...

The arithmetic mean roughness, Ra, values were determined by scanning electron microscopic technique of different core models (furazolidone, nitrofurantoin and acetyl salicylic acid), coated by HPMC film forming solution containing 10 wt% of various molecular weight PEGs. The results showed that both plasticizer molecular weight and core surface free energy could have a significant influence on...