sodium cation
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Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 470
Author(s):  
Josip Požar ◽  
Marija Cvetnić ◽  
Andrea Usenik ◽  
Nikola Cindro ◽  
Gordan Horvat ◽  
...  

The binding of alkali metal cations with two tertiary-amide lower-rim calix[4]arenes was studied in methanol, N,N-dimethylformamide, and acetonitrile in order to explore the role of triazole and glucose functionalities in the coordination reactions. The standard thermodynamic complexation parameters were determined microcalorimetrically and spectrophotometrically. On the basis of receptor dissolution enthalpies and the literature data, the enthalpies for transfer of reactants and products between the solvents were calculated. The solvent inclusion within a calixarene hydrophobic basket was explored by means of 1H NMR spectroscopy. Classical molecular dynamics of the calixarene ligands and their complexes were carried out as well. The affinity of receptors for cations in methanol and N,N-dimethylformamide was quite similar, irrespective of whether they contained glucose subunits or not. This indicated that sugar moieties did not participate or influence the cation binding. All studied reactions were enthalpically controlled. The peak affinity of receptors for sodium cation was noticed in all complexation media. The complex stabilities were the highest in acetonitrile, followed by methanol and N,N-dimethylformamide. The solubilities of receptors were greatly affected by the presence of sugar subunits. The medium effect on the affinities of calixarene derivatives towards cations was thoroughly discussed regarding the structural properties and solvation abilities of the investigated solvents.


Author(s):  
Linden H. Conrad-Marut ◽  
Eric W. Reinheimer ◽  
Adam R. Johnson

The synthesis and crystal structure of the title racemic compound, [Co(C2H8N2)3]Cl3.{[Na(H2O)6]Cl}0.5, are reported. The trivalent cobalt atom, which resides on a crystallographic threefold axis, is chelated by a single ethylene diamine (en) ligand and yields the tris-chelate [Co(en)3]3+ cation with distorted octahedral geometry after the application of crystal symmetry. The sodium cation (site symmetry \overline{3}), has a single water molecule bound to it in the asymmetric unit and yields a distorted, octahedrally coordinated hydrated [Na(H2O)6]+ cation after the application of symmetry. One of the chloride ions lies on a general position and the other has \overline{3} site symmetry. An extensive array of C—H...O, N—H...Cl and O—H...Cl hydrogen bonds exists between the ethylene diamine ligands, the water molecules of hydration, and the anions present, thereby furnishing solid-state stability.


2021 ◽  
Vol 22 (16) ◽  
pp. 8420
Author(s):  
Lanjing Wei ◽  
Huitao Liu ◽  
Kimia Alizadeh ◽  
Maria D. Juarez-Rodriguez ◽  
Roman R. Ganta

Ehrlichia chaffeensis causes human monocytic ehrlichiosis. Little is known about how this and other related tick-borne rickettsia pathogens maintain pH homeostasis in acidified phagosomes and the extracellular milieu. The membrane-bound sodium (cation)/proton antiporters are found in a wide range of organisms aiding pH homeostasis. We recently reported a mutation in an antiporter gene of E. chaffeensis (ECH_0379) which causes bacterial in vivo attenuation. The E. chaffeensis genome contains 10 protein coding sequences encoding for predicted antiporters. We report here that nine of these genes are transcribed during the bacterial growth in macrophages and tick cells. All E. chaffeensis antiporter genes functionally complemented antiporter deficient Escherichia coli. Antiporter activity for all predicted E. chaffeensis genes was observed at pH 5.5, while gene products of ECH_0179 and ECH_0379 were also active at pH 8.0, and ECH_0179 protein was complemented at pH 7.0. The antiporter activity was independently verified for the ECH_0379 protein by proteoliposome diffusion analysis. This is the first description of antiporters in E. chaffeensis and demonstrates that the pathogen contains multiple antiporters with varying biological functions, which are likely important for the pH homeostasis of the pathogen’s replicating and infectious forms.


AIP Advances ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 045118
Author(s):  
David Emin ◽  
Aria Fallah ◽  
Noriko Salamon ◽  
William Yong ◽  
Andrew Frew ◽  
...  

2021 ◽  
Vol 12 (1) ◽  
pp. 39-47
Author(s):  
М. V. Riabovol ◽  
L. V. Bal-Prylypko

In connection with the general deterioration of an ecological situation and the strengthening of negative influence on a state of health of consumers connected with it, researches on development of a compounding of sausages which are characterized by improving properties are carried out. The purpose of the work was to develop the composition of the minced meat composition, which is characterized by minimal sensitivity to oxidants and a balanced mineral composition and gives the product its therapeutic and prophylactic properties. The method of inhibiting the processes of oxidative spoilage of the meat mixture under the action of oxygen by introducing rosemary extract into the mixture is determined. The possibility of reducing the dosage of sodium cation by replacing rock salt with kelp-enriched sea salt was determined, which also allowed to reduce the dosage of toxic sodium nitrite. The study was performed on minced meat. The recipe used minced meat according to DSTU 4436:2005, which includes beef (33%), semi-fat pork (33%) and fatty pork (34%). As a part of meat raw materials of a prototype the content of beef was reduced to 30%, pork semi-fat to 26%, due to inclusion in a compounding of protein of blood plasma (1.0%), orange dietary fibers (0.5%), and also water. for their hydration (7%). As a part of spices and auxiliary materials of a prototype kitchen salt (2.2%) was replaced with sea salt (2.1%), and also the content of sodium nitrite from 0.0075% to 0.0050% due to introduction of rosemary extract ( 0.15%) and the bacterial preparation "Iprovit LRR" (0.05%) to the weight of the stuffing mixture. Experimental and experimental samples of minced meat were prepared with ambassador of raw meat, its aging for two days, hydration of dry blood plasma and orange dietary fiber, mixing all ingredients, filling the resulting mixture of shells, aging the resulting intermediate for 3 hours, its final cooling to 35 ˚C. The dynamics of changes in their peroxide and acid numbers of fat were subject to control. The values of the indicators were determined by standardized methods, and the concentration of sodium chloride - by the Mohr method. Organoleptic quality indicators of sausages of standardized and experimental composition were determined by the method of expert evaluation. Possibility of prolongation of the guaranteed term of storage of sausages from 3 to 10 days is shown and possibility of replacement in forcemeat of rock salt on sea is defined that at preservation of feeling of sufficiency of salinity of a product allowed to reduce dosage of cation of sodium by 30% and to enrich forcemeat with microelements - calcium, magnesium and acute deficiency iodine. A combined recipe for “Ozdorovchi” sausages has been developed, using blood plasma protein and citrus dietary fiber. The developed recipe should be used for industrial production of sausages at meat processing plants.


Author(s):  
Richard Knighton ◽  
Paul D. Beer

A novel method utilising sodium cation templation between a pyridinium bridged calix[4]diquinone macrocycle and a pyridine-N-oxide functionalised macrocycle precursor motif is used for the construction of a mechanically interlocked ion-pair...


2021 ◽  
Vol 273 ◽  
pp. 04011
Author(s):  
Olga Popova ◽  
Tatyana Finochenko

Hydrolytic lignin is a large-tonnage waste product of ethyl alcohol production and is a renewable resource. The structure of lignin is characterized by the presence of a large number of hydroxyl groups, which provides the value of lignin as a raw material for synthesis in polymer chemistry. But due to their low chemical stability in dilute alkalis, acids and solvents, lignins are of little use for wide practical use. The introduction of additional functional groups into the lignin maromolecule by oxidative modification with the use of resource-saving technologies makes it possible to obtain new products for the synthesis of composite materials. On the basis of electrochemically modified lignin in polycondensation reactions with phthalic acid, ion-exchange materials have been obtained: weakly acidic cation exchangers with a exchange capacity of 0.1 mol/l NaOH 3.5-3.8 mmol/cm3, capable of sorbing cations in a wide range of pH values, and ampholyte (exchange capacity for sodium cation 6.4-6.6 mmol/cm3, for chlorine anion - 1.1-1.3 mmol/cm3). Ion exchangers synthesized on the basis of chlorine and nitro-containing lignins have been investigated in comparison with generally known industrial ion exchangers; they have high exchange and physic-mechanical characteristics and chemical resistance.


Water ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 25
Author(s):  
Anna Fadliah Rusydi ◽  
Shin-Ichi Onodera ◽  
Mitsuyo Saito ◽  
Fujio Hyodo ◽  
Morihiro Maeda ◽  
...  

The origin of ammonium-nitrogen in Indonesian coastal groundwater has not been intensively examined, meanwhile the elevated concentration remains a concern. This research aims at tracing the potential sources of ammonium-nitrogen in the groundwater of Indramayu, Indonesia where groundwater is vital for livelihood. From results, a combined examination of nitrogen isotope, coliform bacteria, land-use, and geology confirmed the natural and anthropogenic origins of ammonium-nitrogen in the groundwater. In the brackish-water aquaculture region, groundwater has δ15NNH4 values from +1.8 to +4.8‰ signifying that ammonium-nitrogen is derived from mineralization of organic nitrogen to ammonium. Furthermore, ammonium has a significantly positive relationship with sodium indicating the exchangeable ammonium is mobilized to groundwater via cation exchange. Meanwhile ammonium-nitrogen from anthropogenic waste was detected in agricultural and residential region. The groundwater has more varied δ15NNH4 values, from −2.9 to +16.1‰, which implies attenuation of ammonium-nitrogen from several sources namely manure, mineral fertilizer, sewage, and pit latrines. Also, the presence of E. coli confirms the indication of human and animal waste contamination. However, since ammonium has no relationship with sodium, cation exchange is not feasible and ammonium-nitrogen flows into the groundwater from anthropogenic sources along with liquid wastes.


2020 ◽  
Vol 235 (8-9) ◽  
pp. 341-352
Author(s):  
Stefan Greiner ◽  
Sabine Zitzer ◽  
Sabine Strobel ◽  
Peter S. Berdonosov ◽  
Thomas Schleid

AbstractThe complete series of sodium rare-earth metal(III) chloride oxotellurates(IV) with the composition Na2RE3Cl3[TeO3]4 (RE = Y, La–Nd, Sm–Lu) has been synthesized via solid-state reactions. For these conversions mixtures of the respective rare-earth metal(III) oxides, tellurium dioxide and sodium chloride as flux and reactant were prepared, intimately ground and heated for 5 days at 1225 K. The almost colorless single crystals were characterized via single-crystal X-ray diffractometry. In the monoclinic crystal structure of these compounds two crystallographically different rare-earth metal(III), but only one sodium cation sites occur. [REO8]13− polyhedra around both RE3+ positions as well as sodium-centered polyhedra [NaO4Cl4]8− form layers via different connectivity modes. These layers spread out parallel to the (001) plane and arrange alternatingly resulting in the three-dimensional network of the Na2RE3Cl3[TeO3]4 structure, where the Te4+ lone-pair cations at two different sites work as linkers by forming isolated ψ1-tetrahedra [TeO3]2−. Some of these compounds were represented before in different settings of space group C2/c. Now the complete series of the Na2RE3Cl3[TeO3]4 representatives with RE = Y, La–Nd, Sm–Lu is described consistently for a better comparison and understanding. Additionally, a single crystal of Na2Pr3Cl3[TeO3]4 was measured via energy dispersive X-ray analysis to verify the included elements, powder samples of Na2Nd3Cl3[TeO3]4 were characterized by X-ray diffractometer data for a phase-purity check and a single-crystal Raman spectrum of Na2Yb3Cl3[TeO3]4 served for proving the signature of discrete [TeO3]2− anions.


Author(s):  
M Yu Kalinichenko ◽  
N I Stojanov ◽  
D V Abornev ◽  
S V Ovchinnikova
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