crown ethers 12-crown-4 (12c4), benzo-15-crown-5 (b15c5), 18-crown-6 (18c6), nitrobenzo-18-crown-6 (nb18c6) dibenzo-18-crown-6 (db18c6) and dicyclohexyl-18-crown-6 (dc18c6), dissolved in dichloromethane, are able to form oxonium-ion complexes in contact with aqueous sulfuric and hydrochloric acid solutions. this ability allows the transfer of cr(vi) oxanions from the acid media, through an orga...

background: the fatal effect of ionizing radiation on cells depends on linear energy transfer (let) level. the distribution of ionizing radiation is sparse and homogeneous for low let radiations such as x or γ, but it is dense and concentrated for high let radiation such as heavy-ions radiation. material and methods: chinese hamster ovary cells (cho-k1) were exposed to 4 gy fe-ion 2000 kev/m. ...

BACKGROUND: Some of metal ions as environmental pollutants show estrogenic activity. This xenostrogenic compounds can be caused carcinogenicity in organs. The mechanism of carcinogenicity of metal ions is not clarified. OBJECTIVES: In this study, we investigated the Transcriptional effects of variety of metal ions on the bovine oxytocin and the thymidine kinase-ERE promoter by estrogen receptor...

A binding study of nickel ions by a new recombinant human Growth Hormone (hGH), produced as an injected drug, has been done at 27˚C in NaCl solution (50 mM) using an isothermal titration calorimetry. There is a set of three identical and non-interacting binding sites for nickel ions. The intrinsic dissociation equilibrium constant and the molar enthalpy of binding are 40 μM and -16...

in this work, the removal of copper from an aqueous solution by granular activated carbon (gac) in the presence of competitor ions was studied. a batch adsorption was carried out and different parameters such as ph, contact time, initial copper concentration and competitor ions concentration were changed to determine the optimum conditions for adsorption. the optimum ph required for maximum ads...

The crystal structures are reported of trans-dioxocyclam dihydrate, C(10)H(20)N(4)O(2).2H(2)O, a structural isomer of the well known cis-dioxocyclam, and of its novel Ni complex, (1,4,8,11-tetraazacyclotetradecane-2,9-dionato-kappa(4)N)nickel(II) dihydrate, [Ni(C(10)H(18)N(4)O(2))].2H(2)O, the first example of a transition metal complex of this ligand. Both molecules lie on crystallographic cen...

The applicability of Origanum majorana-Capped Silver nanoparticles synthesis for removing Ni (II) ions from aqueous solutions has been reported. This novel material was characterized by different techniques such as FT-IR, XRD and SEM. The influence of nanoparticle dosage, pH of the sample solution, individual ions concentration, temperature, contact time between the sample and the adsorbent wer...