objective(s) the aims of present study were to elucidate the effect of nahs as a h2s donor on precontracted rat trachea smooth muscle, role of epithelium and nitric oxide in this action. materials and methods tracheal rings from male adult wistar rats were isolated and mounted in an organ bath containing krebs–henseleit solution under 1.5 g resting tension and contractions were recorded isometr...

hydrogen bonding of dppe with water that surrounded of membrane, plays an important role in permeability ofmembrane that we were presented this matter with analysis of bond angles and torsion angles before and after ofadded water molecules.interaction with water molecules causes some changes in the geometry of dppe which were explained bythe contribution of zwitterionic form of dppe molecule, a...

background: in this study, ferrate (vi) and ultraviolet (uv) radiation were employed to remove hydrogen sulfide from municipal wastewater resulting in a reduction in chemical oxygen demand (cod). although ferrate (vi) and uv have been used individually for the removal of a few pollutants from urban and industrial wastewater, there exists no study to investigate the effectiveness of simultaneous...

the thermodynamic of the known and very effective catalytic system, hydrogen peroxide (h2o2) and methyltrioxorhenium (mto) is studied in different solvents using uv-visible spectroscopic method. the thermodynamic parameters (δg, δh and δs) for two equilibrium reactions, mto + h2o2 ⇌ a + h2o and a + h2o2 ⇌ b.h2o (a, [mere(o)2(o2)]; b.h2o, [mere(oh2)(o)(o2)2]), are determined. the obtained free e...

background: new technologies using hazardous materials usually have certain risks. it is more serious when the technology is supposed to be applied in a large scale and become widely used by many people. the objective of this paper was to evaluate the risk of vapor cloud explosion in a hydrogen production process. methods: potential hazards were identified using the conventional hazard identifi...

A UHV atomic hydrogen-cracking cell has been constructed to produce atomic hydrogen in order to perform in-situ cleaning of semiconductor samples. The cell was calibrated and tested with the objective of cleaning the III-V semiconductor samples such as GaAs. Mass spectroscopy studies during the atomic hydrogen cleaning of the GaAs samples revealed the chemical process of the hydrogen cleaning. ...

the preparation of air–fuel mixture is considerably dependent on fluid flow dynamics to achieve improved performance, efficiency, and engine combustion in the appearance of flow. in this study, the effects of mixtures of hydrogen and compressed natural gas (cng) on a spark ignition engine are numerically considered. this article presents the results of a direct-injection engine using methane–hy...

molecular structure, isomerism, conformational stability and intramolecular hydrogen bonding (ihb) of cis-enol forms of 1-(n-pyridyl)butane-1,3-diones (npbd) (n = 2, 3, or 4) have been investigated by means of density functional theory (dft) calculations. energy differences for all possible npbd cis-enol forms of isomers with respect to the most stable form of the corresponding isomer have been...

background protein-bound toxins such as indoxyl sulfate (is) are not efficiently removed by conventional hemodialysis (hd). objectives to improve the removal of is, we performed an in vitro study to evaluate the effects of high dissolved hydrogen on the dissociation of is from albumin using simulated hd. materials and methods wasted dialysate from peritoneal dialysis was concentrated a hundred ...