A comparative research has been developed for acidity and stability constants of M(TTA) and M(Asp) complexes which have been determined by potentiometric pH titration. Depending on metal ion–binding properties, vital differences in building complex were observed. The present study shows that in M(TTA) complexes, metal ions are coordinated to the carboxyl groups, but in M(Asp) some metal ions ar...

a graphene oxide-terpyridine conjugate (gotc) based colorimetric and fluorescent nano-chemosensor was synthesized. it showed high selectivity and sensitivity for fe2+ and fe3+ ions in neutral aqueous solution over other metal ions such as li+, na+, ba2+, ca2+, al3+, cd2+, co2+, cu2+, hg2+, mn2+, ni2+, pb2+, zn2+, cr3+ and ag+. in absorption spectra, upon addition of fe2+ or fe3+, the sensor dis...

abstractin this work, the micro powder was the product of cedar leaf (mpcl) is used as a low-cost adsorbent for the removal of pb2+ ions from aqueous solutions. bath experiments were used to determine the best adsorption conditions the adsorption percentage of pb2+ ions mpcl samples at different initial ph, contact time (tc), adsorbent dosage and temperature (t) were investigated. effective rem...

classical xerogels are robust, inexpensive and nontoxic materials with low-ordered nanoporous structures. in water streams where the ph is higher than the point of zero charge, the surface of classical xerogels such as tetraethoxy orthosilan (teos) xerogel is negatively charged. it was assumed that a xerogel can work as a strong adsorbent for metal ions without further modification. therefore, ...

The efficiency of using a composite of carbon black and sodium bentonite in treating drinking water contaminated with lead and copper ions was analysed. The effects of pH, contact time, concentration and adsorbent dosage using an adsorbent composite of 20 % sodium bentonite and 80 % carbon black were studied. The adsorption data was tested with respect to Langmuir, Freundlich and Temkin iso...

Metal ions are believed to participate in many neurodegenerative conditions. In excitotoxic cell death there is convincing evidence for the participation of Ca(2+) and Zn(2+) ions although the exact molecular mechanisms by which these metals exert their effects are unclear. Only in one instance has the metal binding site of metalloenzymes been exploited for therapeutic purposes and this is the ...

The capability of high-speed countercurrent chromatography (HSCCC) has been investigated for enrichment and determination of metal ions at trace levels. Separation of selected divalent metal ions was performed using a small coiled column. A hexane solution of 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPA) was employed as the stationary phase. Loaded divalent metal ions such as Ni, C...

Sub-critical water (sub-CW) technology was used as a new technology with environmental and financial benefits for the recovery of harmful heavy metal ions Cd (II), Zn (II), Cu (II), Fe (II), Mn (II) and Ni (II) in the waste of Japanese scallop Patinopecten yessoensis. The metals are responsible for environmental problems owing to the large amount of the waste. This study proposes a new method u...

Hammerhead ribozymes have a metal-ion-binding motif in the conserved core region, and this motif can capture several kinds of metal ions. In order to determine what kind of metal ions can be recognized by the motif, we measured 2D 1H-1H NOESY spectra in the presence of various metal ions, such as Cd2+, Na+ and Co(NH3)6(3+) ions, as well as in the absence of these ions. We have completed the ass...

Chelating resins based on polyacrylonitrile and diethylenetriamine (PAN-DTA) wereprepared through the simple reaction of polyacrylonitrile with various volume percents ofdiethylenetriamine (DTA), (25, 50, 75 and 100). The prepared resins were applied to removeheavy metal ions such as Cu(II), Zn(II) and Cd(II) from aqueous solutions. The sorptionbehaviors of the resins for these metal ions were ...