A buffer mixture consist in g of eq ua l molali t ies (m ) of potass ium dihydrogen phospha te and sodium succina te is proposed as a useful reference poin t in the study of acid-base equilibria, b ridging t he present gap be tween pH 5.5 a nd pH 6.8. The p(aH'YCI) at 25 °0 has been determined by elect.romo tive-fo rce measuremen ts for fi ve buffer solu tions in which m varied from 0.005 to 0....

The 35C1 NQ R transition frequencies and the spin-lattice relaxation times, T{, for both lines in p-chlorophenol have been measured in the temperature range 9 0 3 1 0 K. The frequency differ­ ence and the temperature derivatives for both lines clearly show the existence o f two temperature intervals with distinct lattice contributions to the EFG. Similarly, 7", data show a normal be­ haviour du...

A new heterogeneous photocatalyst was prepared by incorporation of methylene blue into ZSM-5 zeolite. This photocatalyst effectively absorbs light in visible range of the spectrum and when irradiated with visible light, it generates reactive oxygen species (ROS) in aqueous environment. Efficiency of the photocatalyst was tested on dechlorination of a model compound 4-chlorophenol and on growth ...

A method for the superheated water chromatography of phenols was developed using a poly(styrene-divinylbenzene) (PSDVB) stationary phase. The stationary phase of superheated water chromatography must be stable against the attack of water. A durability test for PSDVB packings and octadecylsilyl (ODS)-silica gels indicated that PSDVB packings were stable in superheated water in the temperature ra...

Single wall carbon nanotube modified glassy carbon electrode (SWCNT/GCE) was used for flow-injection analysis (FIA) for phenolic compounds (phenol (P), 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorphenol (TCP) and pentachlorophenol (PCP)). Experimental variables such as the detection potential, flow rate and pH of the carrier solution, 0.1 M sodium acetate, were optimized. Under...

in present investigation, zno nanostructure was synthesized by means of a precipitation and sonochemical methods. the x-ray diffraction (xrd) pattern is shown that the wurtzite structure of zno has the hexagonal symmetry and there is no impurity. the average zno particles crystallite size was calculated about 41 nm. the sem and tem images reveal nanostructure zno particles with a cauliflower-li...