Alginate gelling process: Use of bivalent ions rich microspheres

2017 ◽  
Vol 57 (6) ◽  
pp. 531-536 ◽  
Author(s):  
Silvia Vicini ◽  
Marco Mauri ◽  
Joanna Wichert ◽  
Maila Castellano
Keyword(s):  
Process Use ◽  
Bivalent Ions ◽  
Gelling Process

Gelling process of sodium alginate with bivalent ions rich microsphere: Nature of bivalent ions

2016 ◽  
Author(s):  
Marco Mauri ◽  
Silvia Vicini ◽  
Maila Castellano
Keyword(s):  
Sodium Alginate ◽  
Bivalent Ions ◽  
Gelling Process

scholarly journals Solvent-Free Synthesis of Phosphonic Graphene Derivative and Its Application in Mercury Ions Adsorption

Nanomaterials ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 485
Author(s):  
Robert Olszewski ◽  
Małgorzata Nadolska ◽  
Marcin Łapiński ◽  
Marta Prześniak-Welenc ◽  
Bartłomiej Cieślik ◽  
...  
Keyword(s):  
Adsorption Efficiency ◽  
Mercury Ions ◽  
High Adsorption ◽  
Adsorption Selectivity ◽  
Nickel Ions ◽  
Cadmium Ions ◽  
First Order ◽  
Bivalent Ions ◽  
Pseudo Second Order ◽  
Solvent Free Synthesis

Functionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material was used as an efficient mercury adsorbent, showing high adsorption efficiency. The adsorption isotherms were fitted using Freundlich and Langmuir models. The adsorption kinetics were fitted with pseudo-first order and pseudo-second order models. Adsorption selectivity was determined in the presence of cadmium ions and nickel ions. The presence of mentioned bivalent ions in the solution did not affect mercury adsorption efficiency.

Consensus document on ultrasound training in Intensive Care Medicine. Care process, use of the technique and acquisition of professional skills

2014 ◽  
Vol 38 (1) ◽  
pp. 33-40
Author(s):  
J.M. Ayuela Azcárate ◽  
F. Clau-Terré ◽  
R. Vicho Pereira ◽  
M. Guerrero de Mier ◽  
A. Carrillo López ◽  
...  
Keyword(s):  
Intensive Care ◽  
Intensive Care Medicine ◽  
Care Process ◽  
Professional Skills ◽  
Consensus Document ◽  
Process Use

scholarly journals Further properties and possible mechanism of action of adenosine 5′-triphosphate–d-glucose 6-phosphotransferase from rat liver

1967 ◽  
Vol 105 (2) ◽  
pp. 473-482 ◽  
Author(s):  
M. J. Parry ◽  
D G Walker
Keyword(s):  
Catalytic Properties ◽  
Gel Filtration ◽  
Thiol Group ◽  
Acceptor Molecule ◽  
Magnesium Ions ◽  
Purification Procedure ◽  
Inhibitory Effects ◽  
Bivalent Ions ◽  
Low Glucose ◽  
Yeast Hexokinase

1. Magnesium ions are the most effective bivalent ions in the glucokinase reaction. 2. The molecular weight of rat hepatic glucokinase is 48000–49000 as assessed by gel filtration on Sephadex G-100. 3. Anomalous kinetic behaviour at low glucose concentrations appears to be due to the formation during the purification procedure of fragments possessing modified catalytic properties, but is unlikely to be of physiological significance. 4. Extension of previous studies (Parry & Walker, 1966) suggests that glucokinase catalyses a reaction of the random Bi Bi type similar to that of yeast hexokinase. 5. The inhibitory effects of various thiol reagents suggest that a thiol group may be involved at or near the binding site of the acceptor molecule.

Ultra-Low Resistance Ni-Based Contacts to n-InP: the Dependence of Contact Resistivity on the Condition of the Metal-Semiconductor Interface

1993 ◽  
Vol 318 ◽  
Author(s):  
Navid S. Fatemi ◽  
Victor G. Weizer
Keyword(s):  
Deposition Process ◽  
Atomic Ratio ◽  
Contact Resistivity ◽  
Semiconductor Interface ◽  
Near Surface ◽  
Process Use ◽  
Fold Reduction ◽  
Specific Contact ◽  
Order Of Magnitude ◽  
First Time

ABSTRACTNear-theoretical-minimum values of specific contact resistivity, ρc (in the mid-to-low E-8 Ω-cm2 range) have been achieved for Ni-based contacts to moderately doped (2E18 cm−3) n-type InP. In each case these values are an order of magnitude lower than those previously achieved. These ultra-low resistivities are shown to result when the metallurgical interaction rate between the contact metal and the semiconductor is sufficiently reduced. Several methods of reducing the metal-InP reaction rate and thus achieving lowered resistivity values are demonstrated. We show, for instance, that the introduction of a thin (100Å) Au layer at the metal-InP interface retards metal-semiconductor intermixing during sintering and results in a ten-fold reduction in pc. Another method consists of ensuring the perfection of the near-surface InP lattice prior to and during contact deposition process. Use of this technique has enabled us to fabricate, for the first time, Ni-only contacts with pc values in the low E-8 Ω-cm2 range. We present an explanation for these observations that is based upon the magnitude of the In-to-P atomic ratio at the metal-InP interface.

Nonenzymatic Catalysis by Metal Ions and Phosphoric Acid Esters of Hydroxamic Acid Formation

1980 ◽  
Vol 35 (6) ◽  
pp. 727-730
Author(s):  
Oemer Saygin ◽  
Peter Decker
Keyword(s):  
Amino Acids ◽  
Phosphoric Acid ◽  
Metal Ions ◽  
Inorganic Phosphate ◽  
Hydroxamic Acid ◽  
Hydroxamic Acids ◽  
Bivalent Ions ◽  
No Release ◽  
Catalytic Effects ◽  
Acid Esters

Abstract Nonenzymatic catalysis by bivalent ions of Be, Mg, Ca, Zn, Mn, Ni and Co and bioorganic phosphates of the formation of hydroxamic acids from acetate or amino acids has been studied systematically. Increased yields of hydroxamate were observed at particular combinations of reactants. The most prominent increase (ca. 15-fold) was found with acetate and Ni++, and with a combination of ATP and Be++. Among others especially ribose-5-phosphate and glucose-5-phosphate enhanced yields in the presence of most metal ions. Since no release of inorganic phosphate was observed, this effect cannot be interpreted as an evidence for intermediate transhosphorylation reactions; it may also result from simple catalytic effects of metal sugar complexes.

scholarly journals Solvo-thermal Assisted-Synthesis; Experimental and Theoretical Characterization; and Biological Evaluations of Azo-Chelator-Ligand Chelates of Fe(II) and Zn(II) ions

2021 ◽  
pp. 40-56
Author(s):  
Festus Chioma
Keyword(s):  
Condensation Reaction ◽  
Test Methods ◽  
Molar Conductance ◽  
Ionization Mass ◽  
Metallic Ions ◽  
Bivalent Ions ◽  
Iron Sulphate ◽  
Methods Analytical ◽  
Micro Analysis

Background and Objectives: The resistance of microbes against anti-bacteriological drugs leading to countless deaths and terminal ailments remains a basis for concern. Hence, the main interest of this study was to design, synthesize and report unusual compounds with basic hydrophilic moieties plus hydrophobic functions for anti-bacteriological studies. Materials and Methods: Analytical (melting points, micro-analysis (C. H.N.S) magnetic susceptibility (µeff), molar conductance plus solubility test) methods; spectral (Fourier Transform Infrared(FTIR)), electrospray ionization mass spectrometry (ESI-MS), nuclear magnetic resonance (1H- plus 13C-NMR), electronic(UV-Vis)) measurements; theoretical (DFT) evaluations were utilized for the characterization of the chelator and its chelates. All synthesized compounds were examined for antimicrobial and antioxidant potentials while the chelator was singly evaluated for solvent extractive capacity. Results: A nitrogenous based chelator-ligand, (E)-1-(((4,6-dimethylpyrimidin-2-yl)imino)methyl) naphthalen-2-ol(LH) synthesized through reflux-condensation reaction of 2-amino-4,6-dimethylpyrimidine with 2-hydroxy-1-napthaldehyde was acquired. Further reflux of the chelator-ligand with bivalent ions of iron-sulphate and zinc-acetate salts plus 2,2’-bipyridine resulted into separate bivalent-heteroleptic metallic chelates. The deprotonated nitrogen of the amine moiety and carbon of the carbonyl gave rise to the chelator-ligand with N2O2 chromophore detected around the metallic atom in the chelates. The µeff data plus UV-Vis spectral values of the chelates conformed to 6-coordinate octahedral geometry. All the chelates were high spin and non-ionic in dimethylsulfoxide (DMSO). The antimicrobial and antioxidant screening of the compounds presented moderate to fantastic results, while the metallic extractive proficiency of the chelator showed outstanding extractability for Fe2+ and Zn2+ions with an efficiency of 79.34% and 51.92% correspondingly. Conclusion: All the synthesized compounds are novel and demonstrated prospective biological, plus metallic ions’ extractive potentials required for designs plus isolation of products also for such actions.

scholarly journals Coordination Numbers of Bivalent Ions in Organic Solvents

2021 ◽  
Vol 95 (10) ◽  
pp. 2059-2064
Author(s):  
M. A. Orekhov
Keyword(s):  
Experimental Data ◽  
Theoretical Model ◽  
Molecular Dynamic ◽  
Coordination Number ◽  
Organic Solvents ◽  
Organic Molecule ◽  
Dynamic Models ◽  
Coordination Numbers ◽  
A Value ◽  
Bivalent Ions

Abstract Molecular dynamic models are created for properties of bivalent ions in organic solvents. It is shown that molecules of the considered solvents bound to ions via oxygen atoms. A theoretical model is developed that describes the ion coordination number. The coordination number in this model is determined by the ratio between the sizes of the ion and the atom organic molecule bound to it. It is shown that the coordination number depends weakly on the solvent and strongly on the type of ion. A value of 0.13 nm is obtained for the effective size of an oxygen atom bound to a bivalent ion. The constructed theoretical model agrees with the results from molecular dynamic calculations and the available experimental data.

Sign in / Sign up

Export Citation Format

Share Document