scholarly journals Uncommon biphasic behaviour induced by very high metal ion concentrations in HCl/H2O/[P44414]Cl and HCl/H2O/PEG-600 systems

2020 ◽  
Vol 22 (40) ◽  
pp. 23226-23236
Author(s):  
Eris Sinoimeri ◽  
Victor Maia Fernandes ◽  
Jérôme Cognard ◽  
Jorge Fernando Brandão Pereira ◽  
Lenka Svecova ◽  
...  
Keyword(s):  
Metal Ion ◽  
Ion Concentrations ◽  
System P ◽  
High Metal ◽  
Very High ◽  
Peg 600

Large amounts of Fe(iii) or Fe(ii) strongly modify the biphasic behavior of the system P44414Cl/HCl/H2O while large amounts of Fe(iii) induce a biphasic regime for the mixture PEG-600/HCl/H2O.

scholarly journals Forced Biomineralization: A Review

Biomimetics ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 46
Author(s):  
Hermann Ehrlich ◽  
Elizabeth Bailey ◽  
Marcin Wysokowski ◽  
Teofil Jesionowski
Keyword(s):  
Environmental Conditions ◽  
Metal Ion ◽  
Toxic Metal ◽  
Dissolved Metals ◽  
Metal Concentrations ◽  
Ion Concentrations ◽  
Wide Range ◽  
Aqueous Environments ◽  
Protective Structures ◽  
Very High

Biologically induced and controlled mineralization of metals promotes the development of protective structures to shield cells from thermal, chemical, and ultraviolet stresses. Metal biomineralization is widely considered to have been relevant for the survival of life in the environmental conditions of ancient terrestrial oceans. Similar behavior is seen among extremophilic biomineralizers today, which have evolved to inhabit a variety of industrial aqueous environments with elevated metal concentrations. As an example of extreme biomineralization, we introduce the category of "forced biomineralization," which we use to refer to the biologically mediated sequestration of dissolved metals and metalloids into minerals. We discuss forced mineralization as it is known to be carried out by a variety of organisms, including polyextremophiles in a range of psychrophilic, thermophilic, anaerobic, alkaliphilic, acidophilic, and halophilic conditions, as well as in environments with very high or toxic metal ion concentrations. While much additional work lies ahead to characterize the various pathways by which these biominerals form, forced biomineralization has been shown to provide insights for the progression of extreme biomimetics, allowing for promising new forays into creating the next generation of composites using organic-templating approaches under biologically extreme laboratory conditions relevant to a wide range of industrial conditions.

The uncatalysed and nickel(II) catalysed decarboxylation of dihydroxyfumaric acid

1965 ◽  
Vol 18 (8) ◽  
pp. 1197
Author(s):  
RW Hay ◽  
SJ Harvie
Keyword(s):  
Aqueous Solution ◽  
Metal Ion ◽  
Active Species ◽  
Ultraviolet Spectrum ◽  
Ionization Constants ◽  
Keto Form ◽  
Ion Concentrations ◽  
First Order ◽  
High Metal ◽  
Kinetics Of

The kinetics of decarboxylation of dihydroxyfumaric acid have keen studied in aqueous solution at 25�, over a range of pH. At 25�, the thermodynamic ionization constants are 2.7 x 10-2 = and 4.36 x 10-4, indicating the trans enol structure in aqueous solution. The decarboxylation occurs in two consecutive steps to give glycolaldehyde as the final product. The monoanion of dihydroxyfumaric acid with k = 2.69 x 10-2 min-1 is the active species in the reaction. The decarboxylation is catalysed by nickel(II) ions at low metal ion concentrations, but at high metal ion concentrations there is evidence for the formation of catalytically inactive metal complexes. The application of computer techniques to consecutive first-order reactions is discussed. The enol + keto equilibrium of dihydroxyfumaric acid has been studied. In aqueous solution the ultraviolet spectrum indicates that the acid is completely enolized, but exists almost exclusively as the keto form in alkaline solution. The rate constant for the process enol + OH- → keto + OH' is 2.9 l-1 mole sec-1 at 25�.

scholarly journals Metal Ion Concentration within Algal Tissue of Species Growing in Proximity to Tioga River Outflows Affected by Acid Mine Drainage in Northern Pennsylvania

2010 ◽  
Vol 9 (2 and 3) ◽  
Author(s):  
Cheyenne McKibbin ◽  
Kyle Root ◽  
Gregory Carson
Keyword(s):  
Acid Mine Drainage ◽  
Metal Ion ◽  
Mine Drainage ◽  
Algal Species ◽  
Ion Concentration ◽  
Ion Concentrations ◽  
Acid Mine ◽  
Manganese Zinc ◽  
High Metal ◽  
Iron Manganese

In this study, two species of algae from two different areas impacted by acid mine drainage (AMD) were analyzed for metal ion accumulation. The two species of algae collected were Klebsormidium and Entransia. Both algal species are located in an area of high metal ion concentrations and low pH (ranging from 2.28 to 2.89). The study assessed the concentration of iron, manganese, zinc, copper and nickel in the algal tissue. Data shows that both Entransia and Klebsormidium are absorbing or adsorbing iron selectively.

Prediction of Soluble Nickel Removal by Activated Sludge Using Free Metal Ion Concentrations

1987 ◽  
Vol 19 (3-4) ◽  
pp. 439-448 ◽  
Author(s):  
Jeppe S. Nielsen ◽  
Steve E. Hrudey ◽  
Frederick F. Cantwell
Keyword(s):  
Activated Sludge ◽  
Metal Ion ◽  
Municipal Sewage ◽  
Nickel Ion ◽  
Ion Concentrations ◽  
Untreated Sewage ◽  
Nickel Uptake ◽  
Nickel Removal ◽  
Free Metal ◽  
Free Metal Ion

Batch isotherm studies using spiked sewage samples containing a range of total soluble nickel concentrations typical of municipal sewage strongly suggested that it is the free (i.e. uncomplexed) nickel ion that is sorbed by activated sludge. Equations relating nickel uptake by activated sludge to free nickel ion concentrations and the extent of complexation in untreated sewage were developed and applied. Predicted and measured nickel removals generally agreed to within ± 30%.

scholarly journals Pre-treatment of desalination feed seawater by Jordanian Tripoli, Pozzolana, and Feldspar: Batch experiments

2011 ◽  
Vol 17 (2) ◽  
pp. 163-171 ◽  
Author(s):  
Aiman Al-Rawajfeh ◽  
Khaldoon Al-Whoosh ◽  
Dwairi Al ◽  
Ahmad Al-Maaberah ◽  
Amer Tarawneh
Keyword(s):  
Layered Double Hydroxide ◽  
Metal Ion ◽  
Raw Materials ◽  
Batch Experiments ◽  
Initial Concentration ◽  
Considerable Potential ◽  
Ion Concentrations ◽  
Pre Treatment ◽  
Co Precipitation ◽  
Double Hydroxide

In this research, composites of layered double hydroxide (LDH) with three Jordanian natural raw materials; Tripoli (T), Pozzolana (P) and Feldspar (F) were prepared by co-precipitation and have been used for feed seawater pre-treatment. The data reveals that percent adsorption decreased with increase in initial concentration, but the actual amount of adsorbed ions per unit mass of LDH/T-P-F increased with increase in metal ion concentrations. The values of ?Go were negative and within 21 to 26 KJ/mol, while the values of ?Ho and ?So were positive and within the range of 0.1 to 25 KJ/mol. The values of ?H?, ?S?, and ?G? indicate the favorability of physisorption and show that the LDH/T-P-F composites have a considerable potential as adsorbents for the removal of ions from seawater.

Synthesis of CuxNi(1−x)O coral-like nanostructures and their application in the design of a reusable toxic heavy metal ion sensor based on an adsorption-mediated electrochemical technique

2017 ◽  
Vol 4 (1) ◽  
pp. 191-202 ◽  
Author(s):  
Sayan Dey ◽  
Sumita Santra ◽  
Anupam Midya ◽  
Prasanta Kumar Guha ◽  
Samit Kumar Ray
Keyword(s):  
Heavy Metal ◽  
Detection Limit ◽  
Metal Ion ◽  
High Selectivity ◽  
Heavy Metal Ion ◽  
Electrochemical Technique ◽  
Toxic Heavy Metal ◽  
Ion Sensors ◽  
Metal Ion Sensors ◽  
Very High

Nanostructured, Cu-doped nickel oxides serve as excellent, ultra-fast, re-usable heavy metal ion sensors with an ultra-low detection limit and very high selectivity towards toxic Cr(vi) ions.

A study of chromium-exchanged zeolites as potential catalysts for thermolysis of water

1986 ◽  
Vol 64 (7) ◽  
pp. 1332-1339 ◽  
Author(s):  
K. M. Miedzinska ◽  
B. R. Hollebone
Keyword(s):  
Low Temperatures ◽  
Metal Ion ◽  
Redox Cycle ◽  
Zeolite 13X ◽  
Irreversible Reduction ◽  
Very High ◽  
Oxygen Atoms

Evidence was found that the Cr(III)/Cr(II) redox cycle previously described to occur upon dehydration and rehydration of exchanged zeolite 13X, does not occur reversibly. Data suggest dimerization of the metal ion at high levels of exchange. The bridging provideu by the oxygen atoms of the lattice probably stabilize these dimers and lead to initial but irreversible reduction at very low temperatures. Evidence also indicates irreversible formation of new lattices at very high dehydration temperatures.

Influence of implant design on blood metal ion concentrations in metal-on-metal total hip replacement patients

2015 ◽  
Vol 39 (9) ◽  
pp. 1803-1811 ◽  
Author(s):  
Gulraj S. Matharu ◽  
Fiona Berryman ◽  
Lesley Brash ◽  
Paul B. Pynsent ◽  
Ronan B. Treacy ◽  
...  
Keyword(s):  
Total Hip Replacement ◽  
Hip Replacement ◽  
Metal Ion ◽  
Implant Design ◽  
Ion Concentrations ◽  
Total Hip ◽  
Metal On Metal
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