adsorption of cations al, zn, fe, cr and pb from aqueous solution of hydrogen peroxide using ir-120 cation-exchange resin was studied. the removal percentage of the cations was examined by varying experimental conditions (such as ph of the hydrogen peroxide solution, temperature, contact time and dosage of adsorbent) in a stirred-batch system. under the optimal conditions (ph=1, t=25oc, contact...

In this research new adsorbents were prepared by modification of surfactant-coated g-alumina with three ligands; 1-(2-pyridylazo)-2-naphtol (PAN), dithizone (HDZ) and dimetyl golyoxime (DMG). The adsorbents were used for removal and pre-concentration of Pb+2, Cd+2, Ni+2, Cu+2, Co+2. Aqueous solutions of the me...

in this research new adsorbents were prepared by modification of surfactant-coated g-alumina with three ligands; 1-(2-pyridylazo)-2-naphtol (pan), dithizone (hdz) and dimetyl golyoxime (dmg). the adsorbents were used for removal and pre-concentration of pb+2, cd+2, ni+2, cu+2, co+2. aqueous solutions of the metal ions were passed through a column filled with the adsorbent and the retained catio...

Measurement of transmural sodium fluxes across isolated, ouabain-inhibited turtle colon in the presence of a serosal-to-mucosal sodium gradient shows that in the absence of active transport the amiloride-sensitive cellular path contains at least two routes for the transmural movement of sodium and lithium, one a conductive path and the other a nonconductive, cation-exchange mechanism. The latte...

Accurate modeling of multicomponent sorption and transport of major cations in subsurface porous media is a prerequisite for predicting complex environmental processes, such as the movement of trace metals in soils and aquifers. In this study, various cation exchange models were compared in their ability to predict ternary Ca–Mg–Na transport in an acidic soil from binary Ca, Mg, and Na adsorpti...

The nematode Caenorhabditis elegans is attracted by at least four classes of attractants: by cyclic nucleotides, cAMP and cGMP; by anions, Cl(-), Br(-), I(-); by cations, Na(+), Li(+), K(+), Mg(+); and by alkaline pH values. The nematode's behavioral response to gradients of these attractants involves orientation and movement up the gradient, accumulation, and then habitutation. Comparison of t...

The electron impact-induced fragmentation of 2,2-dimethyland 2-ethyI-l,findandione, 1 and 2, and their isomers, 3-isopropylideneand 3-propylidenephthalide, 3 and 4, respectively, was studied in detail by mass-analysed ion kinetic energy (MIKE) and collision-induced dissociation (CID-MIKE) spectrometry, including 'H and I3Clabelled analogues of 1 and 2. In all regimes of internal energy, the mol...

background: silica aerogel is the nano-porous form silica which is the lightest synthetic solid material. some specific properties of this material include high surface area (1500 m2.g-1), low density (< 0.03 g.cm-3) and high porosity (%99). in this research, silica aerogel was investigated as an adsorbent of the heavy metal cations in aqueous solutions. methods: the silica aerogel was synthesi...

Inhibition by polyvalent cations is a defining characteristic of voltage-gated proton channels. The mechanism of this inhibition was studied in rat alveolar epithelial cells using tight-seal voltage clamp techniques. Metal concentrations were corrected for measured binding to buffers. Externally applied ZnCl 2 reduced the H 1 current, shifted the voltage-activation curve toward positive potenti...