introduction climate change is one of the most important challenges in sustainable development, which has a negative impact on aquatic and terrestrial ecosystems. this will change rainfall patterns the power to increase hurricane and the risk of drought, flood and will strengthen pressure on water resources. researchers generally agree that the main cause of the increase in global temperature i...

single-walled carbon nanotubes (swcnt) and multi-walled carbon nanotubes(mwcnt) were melt-blended with polyvinylidene fluoride (pvdf).ft-ir technique revealed that swcnt has insignificant effect on the crystalline structure of pvdf and at 3wt% modification only 14% beta crystal isformed. this observation was accounted for by the chair structure of swcnt. in mwcnt nancomposites it was found that...

Practical application of hydrogen production from water splitting relies strongly on the development of low-cost and high-performance electrocatalysts for hydrogen evolution reaction (HER). The previous researches mainly focused on transition metal nitrides as HER catalysts due to their electrical conductivity and corrosion stability under acidic electrolyte, while tungsten nitrides have report...

Perfluorinated compounds (PFCs) consist by a hydrophobic perfluorinated carbon tail and a hydrophilic ionic headgroup. Because of their unique structure, PFCs have a wide variety of applications including active ingredient in fire fighting foams, impregnation for food packing and waterproof breathable fabrics and the producing of teflon. Recently, the research interest for these compounds has b...

The hydrogenation of carbon monoxide and carbon dioxide on various steel catalysts was studied in the temperature range of 800" to 1,300'F. and at pressures from 5 to 30 atm. The feed gases (3.75 to 20 SCFH) were passed over a catalyst bed of 1/8-h. steel balls supported in a brass-lined reactor 0.81 in. in d i m . The percentage of carbon oxides in the feed was 30% in the runs using a Hz-COZ f...

Oxygen reduction has been studied on gas diffusion electrodes made from various kinds of activated carbon materials. The potentiodynamic method was used to study the electrochemical behavior of the reduction reaction, while nitrogen gas adsorption and powder Xray diffraction were used to determine the pore size distribution and the crystal structure of the carbon material, respectively. The rel...

Aquatic green plants can assimilate carbon dioxide in solutions of widely varying hydrogen-ion concentration. Our purpose in investigating the rate of photosynthesis as a function of this factor was to clarify the interpretation of experiments in carbonate mixtures, where the concentrations of carbonate and bicarbonate ions and of free carbon dioxide all vary with the hydrogen-ion concentration...