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Journal articles on the topic 'Metal ions. Cations'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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1

Buncel, Erwin, Ruby Nagelkerke, and Gregory RJ Thatcher. "Alkali metal ion catalysis in nucleophilic displacement by ethoxide ion on p-nitrophenyl phenylphosphonate: Evidence for multiple metal ion catalysis." Canadian Journal of Chemistry 81, no. 1 (2003): 53–63. http://dx.doi.org/10.1139/v02-202.

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In continuation of our studies of alkali metal ion catalysis and inhibition at carbon, phosphorus, and sulfur centers, the role of alkali metal ions in nucleophilic displacement reactions of p-nitrophenyl phenylphosphonate (PNPP) has been examined. All alkali metal ions studied acted as catalysts. Alkali metal ions added as inert salts increased the rate while decreased rate resulted on M+ complexation with 18-crown-6 ether. Kinetic analysis indicated the interaction of possibly three potassium ions, four sodium ions, and five lithium ions in the transition state of the reactions of ethoxide w

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2

Forughirad, Abdollah, Ataallah Bahrami, Khalil Farhadi, Anahita Fathi Azerbaijani, and Fatemeh Kazemi. "COMPARATIVE OF NATURAL ZEOLITE – CLINOPTILOLITE ELIMINATION OF METAL IONS/ESPECIALLY Cu (II) WITH D-PENICILLAMINE FROM BIOLOGICAL ENVIRONMENTS." Rudarsko-geološko-naftni zbornik 36, no. 4 (2021): 11–19. http://dx.doi.org/10.17794/rgn.2021.4.2.

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Clinoptilolite is used as an adsorbent to remove heavy metal cations due to its function as a molecular sieve. This molecular sieve characteristic has made it possible to study the efficiency of clinoptilolite and D-Penicillamine in a comparative way in terms of the adsorption of heavy metals (especially copper) from a biological medium. For this purpose, clinoptilolite was subjected to grinding to produce a homogenized micronized powder in two sizes with d90=75 and 150 μm. Then, initial adsorption tests in an aqueous medium were performed on 10 ppm solutions of iron, zinc, copper, cadmium and

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3

Mustafa, S., B. Dilara, A. Naeem, N. Rehana, and K. Nargis. "Temperature and pH Effect on the Sorption of Divalent Metal Ions by Silica Gel." Adsorption Science & Technology 21, no. 4 (2003): 297–307. http://dx.doi.org/10.1260/026361703322405033.

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The sorption of Zn2+, Ni2+ and Cd2+ ions by silica gel was studied as a function of ion concentration, pH and temperature. An increase in all three parameters led to an increase in the extent of sorption for all the metal cations studied. The selectivity of the solid was observed to be in the order Zn2+ > Ni2+ > Cd2+. Sorption of the metal cations was accompanied by the release of H+ ions into the bulk phase. On average two moles of H+ ions were released per mole of metal cation sorbed. The sorption data fitted the linear forms of both the Kurbatov and Langmuir adsorption equations. The

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4

Miteva, T., J. Wenzel, S. Klaiman, A. Dreuw, and K. Gokhberg. "X-Ray absorption spectra of microsolvated metal cations." Physical Chemistry Chemical Physics 18, no. 25 (2016): 16671–81. http://dx.doi.org/10.1039/c6cp02606k.

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5

Permyakov, Eugene A. "Metal Binding Proteins." Encyclopedia 1, no. 1 (2021): 261–92. http://dx.doi.org/10.3390/encyclopedia1010024.

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Metal ions play several major roles in proteins: structural, regulatory, and enzymatic. The binding of some metal ions increase stability of proteins or protein domains. Some metal ions can regulate various cell processes being first, second, or third messengers. Some metal ions, especially transition metal ions, take part in catalysis in many enzymes. From ten to twelve metals are vitally important for activity of living organisms: sodium, potassium, magnesium, calcium, manganese, iron, cobalt, zinc, nickel, vanadium, molybdenum, and tungsten. This short review is devoted to structural, physi

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6

Xanthopoulos, Konstantinos, Zafeiria Anagnostou, Sophocles Chalkiadakis, et al. "Platonic Relationships in Metal Phosphonate Chemistry: Ionic Metal Phosphonates." Crystals 9, no. 6 (2019): 301. http://dx.doi.org/10.3390/cryst9060301.

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Phosphonate ligands demonstrate strong affinity for metal ions. However, there are several cases where the phosphonate is found non-coordinated to the metal ion. Such compounds could be characterized as salts, since the interactions involved are ionic and hydrogen bonding. In this paper we explore a number of such examples, using divalent metal ions (Mg2+, Ca2+, Sr2+ and Ni2+) and the phosphonic acids: p-aminobenzylphosphonic acid (H2PABPA), tetramethylenediamine-tetrakis(methylenephosphonic acid) (H8TDTMP), and 1,2-ethylenediphosphonic acid (H4EDPA). The compounds isolated and structurally ch

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7

Qadeer, Riaz, Imtiaz Hanif, and Javed Hanif. "Effect of Different Cations on the Adsorption of Dy3+, Gd3+, Eu3+ and Sm3+ Ions on Activated Charcoal from Aqueous Solutions." Adsorption Science & Technology 13, no. 1 (1996): 27–29. http://dx.doi.org/10.1177/026361749601300104.

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The effect of different cations on the adsorption of Dy3+, Gd3+, Eu3+ and Sm3+ ions on activated charcoal from aqueous solutions (pH = 4.0) has been studied at room temperature (295 ± 1 K). Their effect on the adsorption of the metal ions has been correlated with the charge density (Z/r) of the cations. It was observed that cations with a larger Z/r value reduced the adsorption of metal ions more than cations with smaller Z/r values. It was also observed that the ease of adsorption of the metal ions followed the sequence: Dy3+ > Gd3+ > Eu3+ > Sm3+. Such data are important in relation

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8

Journal, Baghdad Science. "Adsorption of some Metal Ions from Aqueous Solution on Iraqi Rice Bran and Its Relation to the Physical Properties of these Metal Ions." Baghdad Science Journal 11, no. 4 (2014): 1604–11. http://dx.doi.org/10.21123/bsj.11.4.1604-1611.

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Adsorption studies were carried out to test the ability of the Iraqi rice bran (Amber type) to adsorb some metals divalent cations (Cd2+, Co2+, Cu2+, Fe2+, Ni2+, Pb2+, and Zn2+) as an alternative tool to remove these pollutants from water. The Concentrations of these ions in water were measured using flame and flamless atomic absorption spectrophotometry techniques. The applicability of the adsorption isotherm on Langmuir or Freundlisch equation were tested and found to be dependent on the type of ions. The results showed different adsorptive behavior and different capacities of the adsorption

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9

Chawla, Har Mohindra, Satya Narayan Sahu, and Rahul Shrivastava. "Synthesis and binding characteristics of novel calix[4]arene(amidocrown) diquinones." Canadian Journal of Chemistry 87, no. 3 (2009): 523–31. http://dx.doi.org/10.1139/v09-007.

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A series of new calix[4]arene(amidocrown) diquinones (3a–3d) have been synthesized, characterized, and evaluated for cation recognition. It has been observed that 3b interacts with alkali metal ions (Li+, Na+, and K+) and ammonium ions to induce an unprecedented downfield shift in the NH proton resonance, which can be attributed to polarization of the amidocrown ring of the calix[4]arene diquinone receptor. The observation has been confirmed by a significant anodic shift (Li+ > NH4+ > Na+> K+) of the corresponding amidocrown-diquinone redox couple in cyclic and square wave voltammetri

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10

Jovic-Jovicic, Natаsa, Aleksandra Milutinovic-Nikolic, Marija Zunic, et al. "Organobentonites as multifunctional adsorbents of organic and inorganic water pollutants." Journal of the Serbian Chemical Society 79, no. 2 (2014): 253–63. http://dx.doi.org/10.2298/jsc130125065j.

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The aim of this study was to find a low cost, easy to synthesize and efficient adsorbent for the simultaneous adsorption of both organic and inorganic pollutants (including textile dyes, toxic metals etc.). The starting material, domestic bentonite clay from Bogovina was modified with amounts of hexadecyltrimethylammonium cations corresponding to 0.5 and 1.0 times of the value of the cation exchange capacity value. The organobentonites were tested as adsorbents in a three-dye-containing solution, a three-component solution of Pb2+, Cd2+ and Ni2+ and a hexa- component solution containing all in

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11

JUSSIPBEKOV, U. Zh, R. M. CHERNYAKOVA, A. A. АGATAYEVA, N. N. KOZHABEKOVA, R. А. KAIYNBAYEVA, and G. Sh SULTANBAYEVA. "SORPTION OF HEAVY METAL CATIONS FROM A WATER-SALT SYSTEMBY NATURAL MONTMORILLONITE." Chemical Journal of Kazakhstan 73, no. 1 (2021): 204–12. http://dx.doi.org/10.51580/2021-1/2710-1185.22.

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The sorption properties of natural montmorillonite from the Tagan deposit with respect to heavy metal cations were researched on the model system "Mn2+–Co2+– Ni2+–V4+–H2O–montmorillonite". The influence of temperature, duration of the process and concentration of solutions, as well as the norm of the sorbent on the degree of sorption of cations is considered. The optimal conditions for the sorption process (25о С, 30 min, Т:Ж = 1,5:100) have been determined, at which the degree of solution purification is up to 86.36% cations of Co2+, 85.59% of Ni2+, 82.64% of Mn2+ and 52.29% of V4+. The natur

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12

Lemishka, Mariia, Jiri Dedecek, Kinga Mlekodaj, Zdenek Sobalik, Stepan Sklenak, and Edyta Tabor. "Speciation and siting of divalent transition metal ions in silicon-rich zeolites. An FTIR study." Pure and Applied Chemistry 91, no. 11 (2019): 1721–32. http://dx.doi.org/10.1515/pac-2018-1228.

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Abstract Speciation and location of Co2+, Mn2+ and Ni2+ in the extraframework positions of the dehydrated zeolite matrix of ferrierite structure were studied in detail using FTIR spectroscopy of antisymmetric T–O–T vibrations of the zeolite framework. Me2+–ferrierites were prepared by the ion exchange of the NH4– and Na–zeolite forms and by impregnation of the NH4 form. Bare Me2+ occupies all three known cationic sites in dehydrated cationic zeolite. The wavenumbers of bands of individual cations in individual sites were identified. At low Me2+ loadings (Me2+/Al < 0.15), Me2+ replaces two p

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13

Kruk, Mikalai M., Aleksander S. Starukhin, Nugzar Zh Mamardashvili, Galina M. Mamardashvili, Yulia B. Ivanova, and Olga V. Maltseva. "Tetrapyrrolic compounds as hosts for binding of halides and alkali metal cations." Journal of Porphyrins and Phthalocyanines 13, no. 11 (2009): 1148–58. http://dx.doi.org/10.1142/s1088424609001492.

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In this paper the binding of halides and alkali metal cations with porphyrin hosts is reported. The halide ions are complexed with diprotonated porphyrin macrocycle with high affinity and stable complexes of 1:1 and 1:2 structures with halide ions are formed. Strong (up to 300 times) quenching of the porphyrin fluorescence has been found upon the titration of porphyrin solutions with iodide ions. It was established that both static quenching upon formation of the non-fluorescent complex and dynamic diffusion-controlled quenching took place. It is shown that the halide ions binding isotherms ca

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14

Rosenbach, Hannah, Jan Borggräfe, Julian Victor, et al. "Influence of monovalent metal ions on metal binding and catalytic activity of the 10–23 DNAzyme." Biological Chemistry 402, no. 1 (2020): 99–111. http://dx.doi.org/10.1515/hsz-2020-0207.

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AbstractDeoxyribozymes (DNAzymes) are single-stranded DNA molecules that catalyze a broad range of chemical reactions. The 10–23 DNAzyme catalyzes the cleavage of RNA strands and can be designed to cleave essentially any target RNA, which makes it particularly interesting for therapeutic and biosensing applications. The activity of this DNAzyme in vitro is considerably higher than in cells, which was suggested to be a result of the low intracellular concentration of bioavailable divalent cations. While the interaction of the 10–23 DNAzyme with divalent metal ions was studied extensively, the i

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15

Matsushita, Alan F. Y., María José Tapia, Alberto A. C. C. Pais, and Artur J. M. Valente. "Luminescent Properties of Lanthanoid-Poly(Sodium Acrylate) Composites: Insights on the Interaction Mechanism." Polymers 12, no. 6 (2020): 1314. http://dx.doi.org/10.3390/polym12061314.

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The interaction between polyelectrolytes and metal ions is governed by different types of interactions, leading to the formation of different phases, from liquid state to weak gels, through an appropriate choice of metal ion/polyelectrolyte molar ratio. We have found that lanthanide ions, europium(III) and terbium(III), are able to form polymer composites with poly(sodium acrylate). That interaction enhances the luminescent properties of europium(III) and terbium(III), showing that Eu3+/poly(sodium acrylate) (PSA) and Tb3+/PSA composites have a highly intense red and green emission, respective

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16

Yurdakul, H., та S. Turan. "The Valance Determination of Cerium Ions in α-SiAlON by Electron Energy Loss Spectroscopy Analysis". Microscopy and Microanalysis 14, S3 (2008): 19–22. http://dx.doi.org/10.1017/s1431927608089265.

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SiAlON ceramics have found applications in many different areas due to their excellent engineering properties such as high hardness, fracture toughness, good thermal shock and oxidation resistance. SiAlON exist mainly in two different polymorphs: a (MxSi12-(m+n)Al(m+n)OnN16-n; M: metal and rare earth cations, x≈0,35 and n≤1,35) and β (β-Si6-zAlzOzN8-z; 0≤z≤4). In general, stable alpha and beta phases separately as well as in combination of α and β are obtained by incorporation of metal and rare earth cations as sintering additives. The metal cations such as Li, Mg, Ca, Y, and most lanthanide c

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17

Andjelkovic, Tatjana, Jelica Perovic, Milovan Purenovic, and Darko Andjelkovic. "Destabilization and aggregation of aqueous humic acids solution by metal ions." Facta universitatis - series: Physics, Chemistry and Technology 3, no. 1 (2004): 79–85. http://dx.doi.org/10.2298/fupct0401079a.

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The aggregation of soil humic acid (HA) after addition of cations was investigated by nephelometric measurements of HA solution turbidity. Here we show that aggregation is promoted by the presence of positive ions in the solution and that the order of increasing effectiveness in turbidity follows Schulze-Hardy rule. Also, the obtained results indicate that the cation with the largest ionic radius within a common valence is the most effective coagulant. Influence of unions follows the sequence: chloride < nitrate < sulphate, but it is insignificant comparing the influence of cation. This

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18

Powell, J. J., R. Jugdaohsingh, and R. P. H. Thompson. "The regulation of mineral absorption in the gastrointestinal tract." Proceedings of the Nutrition Society 58, no. 1 (1999): 147–53. http://dx.doi.org/10.1079/pns19990020.

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The absorption of metal ions in the mammalian single-stomached gut is fortunately highly selective, and both luminal and tissue regulation occur. Initially, assimilation of metal ions in an available form is facilitated by the intestinal secretions, chiefly soluble mucus (mucin) that retards hydrolysis of ions such as Cu, Fe and Zn. Metal ions then bind and traverse the mucosally-adherent mucus layer with an efficiency M+> M2+> M3+. At the mucosa Fe3+is probably uniquely reduced to Fe2+, and all divalent cations (including Fe2+) are transported by a membrane protein (such as divalent cat

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19

Wang, Jin-Gui, Yabo Wang, Hongzhong Chen, Jiesheng Lim, Takashi Tatsumi, and Yanli Zhao. "Cation-exchange resin towards low-cost synthesis of high-performance TS-1 zeolites in the presence of alkali-metal ions." RSC Advances 6, no. 19 (2016): 15615–21. http://dx.doi.org/10.1039/c5ra23871d.

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20

Gavriloaiei, T., Raluca Mocanu, Maria Calistru, and R. Olariu. "COMPARATIVE STUDY OF BIOSORPTION OF METALLIC CATIONS BY DIFFERENT BACTERIA." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 6, no. 6 (1998): 33–44. http://dx.doi.org/10.48141/sbjchem.v6.n6.1998.35_1998.pdf.

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Certain species of microorganisms have been found to accumulate surprisingly large quantities of important metals, involved in the toxicity provoked by human activities (Cd, Pb, Hg) and metals of economic values (Ag, Au). Microbiological methods are applied to large-scale recovery or removal of metallic ions from aqueous solutions. These applications involved the removal of heavy metals from sewage sludge, industrial effluents, and mine or wastewaters. This process has been developed using immobilized extracellular or cellular ligands or more simple chemical models based upon them. The uptake

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21

Constable, Edwin C., and Catherine E. Housecroft. "Halide Ion Embraces in Tris(2,2′-bipyridine)metal Complexes." Crystals 10, no. 8 (2020): 671. http://dx.doi.org/10.3390/cryst10080671.

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An analysis of the [M(bpy)3]n+ (bpy = 2,2′-bipyridine) complexes with halide counterions in the Cambridge Structural Database reveals a common structural motif in two thirds of the compounds. This interaction involves the formation of 12 short C–H…X contacts between halide ions lying within sheets of the cations and H-3 and H-3′ of six [M(bpy)3]n+ complex cations. A second motif, also involving 12 short contacts, but with H-6 and H-5, is identified between halide ions lying between sheets of the [M(bpy)3]n+ cations.

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22

Robinson, John J. "Selective metal ion binding at the calcium-binding sites of the sea urchin extraembryonic coat protein hyalin." Biochemistry and Cell Biology 67, no. 11-12 (1989): 808–12. http://dx.doi.org/10.1139/o89-119.

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The interaction of metal ions with the sea urchin extraembryonic coat protein hyalin was investigated. Hyalin, immobilized on nitrocellulose membrane, bound Ca2+ and this interaction was disrupted by ruthenium red and selective metal ions. The divalent cations Cd2+ and Mn2+, when present at a concentration of 30 μM, displaced hyalin-bound Ca2+. In competition assays, 1 mM Cd2+ or 3 mM Mn2+ were effective competitors with Ca2+ for binding to hyalin. Cobalt, at a concentration of 30 μM, was unable to displace protein-bound Ca2+, but was effective in competition assays at a concentration of at le

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Lau, T. C., P. O. Ang, and P. K. Wong. "Development of seaweed biomass as a biosorbent for metal ions." Water Science and Technology 47, no. 10 (2003): 49–54. http://dx.doi.org/10.2166/wst.2003.0536.

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Three seaweed species collected from Hong Kong waters were screened for their adsorption abilities for Cu2+, Ni2+ and Zn2+; and Ulva lactuca having the highest metal ion removal capacity (RC) was chosen for further study. Effects of algal biomass and medium pH on the metal ions RC of Ulva lactuca were determined and optimized. Under the optimal conditions of the corresponding metal ions, the algal Cu2+, Ni2+ and Zn2+ RCs were 65.54, 21.00 and 49.54 mg/g, respectively. The presence of other cations and anions affected the metal ions adsorption by the seaweed. The effect was dependent on the com

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Böhme, Diethard K. "Gaseous ions and chemical mass spectrometry." Canadian Journal of Chemistry 86, no. 3 (2008): 177–98. http://dx.doi.org/10.1139/v07-146.

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The intrinsic chemical reactivities of ions can be monitored in the gas phase using mass spectrometers that are coupled to appropriate ion sources and reaction cells. Here the author surveys his own experiences over the past 40 years as an ion chemist. He used flow-tube techniques for room temperature measurements of the intrinsic chemical reactivities of a large variety of positive and negative ions, including bare atomic ions, ions found in solution, biological ions, carbonaceous ions, and interstellar, cometary, and ionospheric ions. Progress in the measurement of chemical reactions of thes

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Pérez-Ponce, Amparo, and Bernhard Lendl. "Mid-IR Spectroscopy for the Quantification of Metal Ions in Aqueous Solution in the Nanogram Range." Applied Spectroscopy 54, no. 5 (2000): 676–80. http://dx.doi.org/10.1366/0003702001950157.

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A novel mid-infrared (IR) flow-through sensor system for the determination of metal ions in aqueous solution was developed. The flow-through sensor comprised weak cation exchanger beads (Sephadex with carboxylic acid moieties) placed in the optical path of a 37 μm IR transmission cell. The combination of the flow-through sensor with a sequential injection analysis (SIA) system allowed us to carry out the whole analysis procedure including analyte–sensor interaction and sensor regeneration, as well as data acquisition, under computer control. The first step of an analysis sequence was regenerat

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Costa, Alexandra I., Patrícia D. Barata, and José V. Prata. "Fluorescent Calix[4]arene-Oxacyclophane Sensor for Transition Metal Cations." Chemistry Proceedings 3, no. 1 (2020): 40. http://dx.doi.org/10.3390/ecsoc-24-08453.

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The sensing behavior of a calix[4]arene-oxacyclophane-carbazole conjugate (1) towards Cu(I) ions was investigated. Contrary to the noteworthy sensitivity and selectivity previously found for Cu(II), the affinity of 1 for Cu(I) cations is much lower. Through fluorescence titration assays, the apparent binding constants (Ka) for the two ions were determined, showing that an affinity of over thirteen fold was displayed for Cu(II). Two Cu(I) counter-ions were used to determine possible effects on the binding event. It was found that acetate and iodide ions behave similarly, yielding Ka of the same

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27

Hind, A. R., S. K. Bhargava, W. Van Bronswijk, S. C. Grocott, and S. L. Eyer. "On the Aqueous Vibrational Spectra of Alkali Metal Oxalates." Applied Spectroscopy 52, no. 5 (1998): 683–91. http://dx.doi.org/10.1366/0003702981944355.

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Fourier transform infrared attenuated total reflectance and Fourier transform Raman spectra of the series of aqueous alkali metal oxalates—lithium oxalate (Li2C2O4), sodium oxalate (Na2C2O4), potassium oxalate (K2C2O4), rubidium oxalate (Rb2C2O4), and cesium oxalate (Cs2C2O4)—are presented for the first time. Fourier transform Raman spectra of the solid oxalates are also presented for the first time. The solid and aqueous oxalate ions are assumed to possess D2 h and D2 d symmetry, respectively, and the assignment of fundamental vibrational modes is made accordingly. The effect of increasing al

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Mustafa, S., B. Dilara, A. Naeem, N. Rahana, and P. Shahida. "Sorption of Metal Ions on a Mixed Oxide [0.5 M SiO2:0.5 M Fe(OH)3]." Adsorption Science & Technology 20, no. 3 (2002): 215–30. http://dx.doi.org/10.1260/026361702760254414.

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The sorption of Zn2+, Ni2+, Cd2+, Ca2+ and Mg2+ ions on to a mixed oxide of iron and silicon was found to increase with increasing temperature, concentration and pH of the system. The selectivity of this mixed oxide was Cd2+ ≥ Zn2+ ≥ Ni2+ > Ca2+ > Mg2+, indicating that the mixed oxide was more selective as an exchanger towards Cd2+ ions relative to its components, SiO2 and Fe(OH)3. The sorption data fitted the linear forms of the Kurbatov and Langmuir adsorption equations. The sorption of metal cations was accompanied by the release of H+ ions to the bulk phase. On average 1 mol H+ was r

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Sergeeva, L. E., and L. I. Bronnikova. "Cell selection with heavy metal ions for obtaining wheat and maize forms tolerant to osmotic stresses." Faktori eksperimental'noi evolucii organizmiv 22 (September 9, 2018): 318–22. http://dx.doi.org/10.7124/feeo.v22.968.

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Aim. The obtaining tolerant to salt and water stresses wheat and maize variants via cell selection with barium and cadmium heavy metal cations were the idea. Barium cations disrupt the cell potassium transport. Cadmium cations affect the dehydrins. The maintenance of these parameters under stress conditions provides the plant tolerance. Methods. Modified media for initial selection were developed by the supplement of the lethal doses of heavy metal ions. Wheat and maize suspension cultures were plated on selective media. The relative fresh biomass growth was the marker of variant stress tolera

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Xiao, Dawei, Zhongzheng Cai, and Loi H. Do. "Accelerating ethylene polymerization using secondary metal ions in tetrahydrofuran." Dalton Transactions 48, no. 48 (2019): 17887–97. http://dx.doi.org/10.1039/c9dt04288a.

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Park, Sang-Hyun, Nahyun Kwon, Jee-Hyeon Lee, Juyoung Yoon, and Injae Shin. "Synthetic ratiometric fluorescent probes for detection of ions." Chemical Society Reviews 49, no. 1 (2020): 143–79. http://dx.doi.org/10.1039/c9cs00243j.

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Lovinger, D. M. "Inhibition of 5-HT3 receptor-mediated ion current by divalent metal cations in NCB-20 neuroblastoma cells." Journal of Neurophysiology 66, no. 4 (1991): 1329–37. http://dx.doi.org/10.1152/jn.1991.66.4.1329.

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1. The effect of micromolar concentrations of divalent metal cations on ion current activated by 5-hydroxytryptamine (5-HT) was investigated in NCB-20 neuroblastoma cells by the use of the whole-cell, patch-clamp technique. 2. Ion current activated by 5-HT in these cells was mimicked by 5-HT3 receptor agonists, blocked by nanomolar concentrations of selective 5-HT3 receptor antagonists and reversed polarity at approximately 0 mV. These properties indicate that this current is carried primarily if not exclusively by the nonspecific cation channel activated by the 5-HT3 receptor. 3. The Group II

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Town, Raewyn M. "Metal ion complexation by soft nanoparticles: the effect of Ca2+ on electrostatic and chemical contributions to the Eigen-type reaction rate." Environmental Chemistry 12, no. 2 (2015): 130. http://dx.doi.org/10.1071/en14086.

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Environmental context The speciation of trace metals in the environment is often dominated by complexation with natural organic matter such as humic acid. Humic acid is a negatively charged soft nanoparticle and its electrostatic properties play an important role in its reactivity with metal ions. The presence of major cations, such as Ca2+, can decrease the effective negative charge in the humic acid particle body and thus modify the chemodynamics of its interactions with trace metal ions. Abstract The effect of Ca2+ on the chemodynamics of PbII complexation by humic acid (HA) is interpreted

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Lin, Lin, Lei Jiang, Hongzhen Guo, Li Yang, and Zizheng Liu. "Optimization of divalent metal cations for maximal concentration of Monacolin K in Monascus M1 by response surface methodology." Czech Journal of Food Sciences 37, No. 5 (2019): 312–18. http://dx.doi.org/10.17221/74/2019-cjfs.

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Inorganic salts are important factors in the growth and secondary metabolites production of microorganisms. This study investigated the influences of divalent metal cations, Mn2+, Zn2+, and Mg2+ on the cell growth and Monacolin K production in Monascus M1. Then the concentration of the three kinds of divalent metal cations was optimized by response surface methodology, and the optimum conditions for the highest production of Monacolin K were determined. The optimum concentrations of the three divalent metal ions were selected as follow: Mn2+ 0.33%, Zn2+ 0.16%, and Mg2+ 1%. In this condition th

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Nocchetti, Morena, Anna Donnadio, Eleonora Vischini, et al. "Zirconium Carboxyaminophosphonate Nanosheets as Support for Ag Nanoparticles." Materials 12, no. 19 (2019): 3185. http://dx.doi.org/10.3390/ma12193185.

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A layered insoluble inorganic-organic solid, namely zirconium phosphate glycine-N,N-bismethylphosphonate, was used to prepare dispersions of nanosheets to support active metals such as metallic silver nanoparticles and zinc ions. Zr phosphate-phosphonate microcrystals were first exfoliated with methylamine to produce a stable colloidal dispersion and then the methylamine was removed by treatment with hydrochloric acid. The obtained colloidal dispersion of Zr phosphate-phosphonate nanosheets was used to immobilize silver or zinc cations, via ion exchange, with the acidic protons of the sheets.

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36

Das, Babulal, and Jubaraj B. Baruah. "Coordinated cations in dipicolinato complexes of divalent metal ions." Inorganica Chimica Acta 363, no. 7 (2010): 1479–87. http://dx.doi.org/10.1016/j.ica.2010.01.025.

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Rizzo, D. M., R. A. Blanchette, and M. A. Palmer. "Biosorption of metal ions by Armillaria rhizomorphs." Canadian Journal of Botany 70, no. 8 (1992): 1515–20. http://dx.doi.org/10.1139/b92-190.

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Armillaria rhizomorphs consist of differentiated hyphae with a melanized outer cortex. Melanin is known to prevent lysis of fungal structures by hydrolytic enzymes and may protect against antagonistic microorganisms. Our studies indicate that melanized rhizomorphs also adsorb high concentrations of cations from the surrounding soil environment. Rhizomorphs of four Armillaria species (A. ostoyae (Romagn.) Herink, A. calvescens Bérubé & Dessureault, A. gemina Bérubé & Dessureault, and A. sinapina Bérubé & Dessureault) collected from Minnesota, New Hampshire, and Oregon had substantia

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38

Frydrych, Roman, Thomas Muschter, Irene Brüdgam, and Hans Hartl. "Synthese und Strukturuntersuchungen von Iodocupraten(I) XII. [(DMF)2H]∞1Me3X4]-Halogenometallate(I) mit neuartigen Tetraederdreifachketten [1] / Syntheses and Structure Analyses of Iodocuprates(I) XII. [(DMF)2H]∞1[Me3X4]-Halometallates(I) with New Tetrahedratriple Chains [1]." Zeitschrift für Naturforschung B 45, no. 5 (1990): 679–88. http://dx.doi.org/10.1515/znb-1990-0516.

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N,N-Dimethylformamidinium-halometallates(I), [(DM F)2H][Me3X4] with Me3X4 = Cu3I4-, Cu3I2Br2-, Cu3I3Cl-, Ag2CuI4-, Ag3I4-, Ag3I3Br- and Ag3I3Cl- were obtained by reacting Cul or Agl with HI, HBr or HC1 in DMF. The crystal structures of the isostructural compounds (space group Pccn) are built by hydrogen-bridged DMF molecules, (DMF)2H+, as cations and a new type of polymeric anion formed by edge sharing tetrahedra triple chains. The chains consist of a double layer of halogen atoms where Cu(I) and Ag(I) cations are located in tetrahedral holes. There are two kinds of halogen positions in the ch

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39

Fiallo, Marina M. L., Hayet Tayeb-Bel Haj, and Arlette Garnier-Suillerot. "Degradation of Anthracycline Antitumor Compounds Catalysed by Metal Ions." Metal-Based Drugs 1, no. 2-3 (1994): 183–93. http://dx.doi.org/10.1155/mbd.1994.183.

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The influence of some metal ions on the degradation of anthracyclines was examined. One of the degradation products is the 7,8-dehydro-9,10-desacetyldoxorubicinone, D* (¥), usually formed by hydrolysis at slightly basic pH. D* is a lipophilic compound with no cytostatic properties. Its formation could be responsible for the lack of antitumor activity of the parent compound. The coordination of metal ions to anthracycline derivatives is required to have degradation products. Cations such as Na+, K+, or Ca2+ do not induce the D* formation however metals which can form stable complexes with doxor

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40

Gagné, Olivier Charles, and Frank Christopher Hawthorne. "Bond-length distributions for ions bonded to oxygen: results for the non-metals and discussion of lone-pair stereoactivity and the polymerization of PO4." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 74, no. 1 (2018): 79–96. http://dx.doi.org/10.1107/s2052520617017541.

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Bond-length distributions are examined for three configurations of the H+ ion, 16 configurations of the group 14–16 non-metal ions and seven configurations of the group 17 ions bonded to oxygen, for 223 coordination polyhedra and 452 bond distances for the H+ ion, 5957 coordination polyhedra and 22 784 bond distances for the group 14–16 non-metal ions, and 248 coordination polyhedra and 1394 bond distances for the group 17 non-metal ions. H...O and O—H + H...O distances correlate with O...O distance (R 2 = 0.94 and 0.96): H...O = 1.273 × O...O – 1.717 Å; O—H + H...O = 1.068 × O...O – 0.170 Å.

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41

Малахова, И. И., В. Д. Красиков, Н. И. Горшков, А. Н. Беляев, and С. М. Староверов. "Planar complexation chromatography of transition metal ions." Сорбционные и хроматографические процессы 17, no. 4 (2018): 682–88. http://dx.doi.org/10.17308/sorpchrom.2017.17/428.

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The method for analysis of transition metal ions (Zn(II), Cu(II), Со(II), Ni(II), Fe(III)) by high-performance planar (thin layer) chromatography with the use of sorbents modified by chelating fragments of iminodiacetic acid was developed. The correlation between retention factor (Rf) and physico-chemical parameters of the separated systems was studied. It was demonstrated that unlike the pH value, ionic strength of a solution does not exert significant influence on resolution and mobility of transition metal cations

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Agnes, George R., and Gary Horlick. "Determination of Solution Ions by Electrospray Mass Spectrometry." Applied Spectroscopy 48, no. 6 (1994): 655–61. http://dx.doi.org/10.1366/000370294774368965.

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Spectral results are presented illustrating the capability of electrospray mass spectrometry (ES-MS) for the determination of the composition of solution samples. The solution components that can be determined include the elemental and molecular forms of anions and cations. Three modes of positive-ion ES-MS are described: the ion cluster mode, the metal-ion mode, and an intermediate mode. The modes are established by operating the electrospray source at specific voltages and curtain gas flow rate values, and each mode provides a unique mass spectral picture of the solution components with prim

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Blake, Alexander J., Wan-Sheung Li, Vito Lippolis, Simon Parsons, and Martin Schröder. "Extended structures of polyiodide salts of transition metal macrocyclic complexes." Acta Crystallographica Section B Structural Science 63, no. 1 (2007): 81–92. http://dx.doi.org/10.1107/s0108768106041668.

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The structures of five polyiodide salts, [Co([9]aneS3)2]I11 (1), [Ni([9]aneS3)2]I6 (2), [Ni([9]aneS3)2]I10 (3), [Pd([12]aneS4)]I6 (4) and [Pd([14]aneS4)]I10·MeCN (5), containing the template cations [Co([9]aneS3)2]3+, [Ni([9]aneS3)2]2+, [Pd([12]aneS4)]2+ and [Pd([14]aneS4)]2+ ([9]aneS3 = 1,4,7-trithiacyclononane, [12]aneS4 = 1,4,7,10-tetrathiacyclododecane, [14]aneS4 = 1,4,8,11-tetrathiacyclotetradecane) exhibit a range of polyiodide and polyanionic framework structures. In (1) the charge on the CoIII cation is balanced by three I_3^- anions, which along with a neutral di-iodine molecule form

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Ceylan, H., T. Şahan, R. Gürkan, and Ş. Kubilay. "Removal of Some Heavy Metal Cations from Aqueous Solution by Adsorption onto Natural Kaolin." Adsorption Science & Technology 23, no. 7 (2005): 519–34. http://dx.doi.org/10.1260/026361705775212475.

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The adsorption removal of some heavy metal cations such as Cu(II), Zn(II) and Co(II) from aqueous solution onto kaolin has been studied using the batch method with initial metal ion concentrations within the range 15–70 mg/l. The percentage adsorption and equilibrium concentrations were determined by means of atomic absorption flame photometry as a function of adsorbate concentration, pH and temperature. Ion-exchange studies showed that over the complete concentration range studied the adsorption ratios for metal cations adsorbed onto kaolin correlated with the linear forms of the Langmuir, Fr

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Stefan, Mircea, Adriana Bors, Daniela Simina Stefan, Ionut Alexandru Savu Radu, and Cicerone Marinescu. "Sorption of Heavy Metal on Natural Clay." Revista de Chimie 68, no. 12 (2018): 2804–7. http://dx.doi.org/10.37358/rc.17.12.5982.

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Sorption of heavy metals on Na-montmorillonite was studied as a function of solution pH and different concentrations of background electrolyte and also a function of added metal ion at constant pH. Equilibrium isotherms have been measured and analyzed using a Langmuir isotherm model. The metal ions were predominantly adsorbed on the permanent charge sites in a easily replaceable state. There was also evident a substantial involvement of the hydroxyl groups on the edges of Na-montmorillonite in specific adsorption of the cations especially at higher pH.

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46

Rowatt, E., and R. J. P. Williams. "The interaction of cations with the dye arsenazo III." Biochemical Journal 259, no. 1 (1989): 295–98. http://dx.doi.org/10.1042/bj2590295.

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1. The dye arsenazo III combines with a selection of cations to give an altered absorption spectrum. 2. Large metal cations such as Ca2+, La3+ and quadrivalent cations give a 1:1 complex with two new absorption peaks at about 610 nm and 655 nm and a KD of about 10(-6) M. 3. Aliphatic polyamines and complex cobalt ions give a 1:1 complex, with one absorption peak at about 610 nm and a KD from 10(-6) to 10(-3) M. 4. Small metal cations finally form a 2:1 complex and also have one absorption peak at about 610 nm, but with a KD of 10(-5)-10(-4) M. 5. The absorption peak at 610 nm is similar to tha

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47

Wanjari, S. M., Lata Deshmukh, and L. J. Paliwal. "Chromatographic Separation of Heavy Metal Cations on a Silica Gel-G with Amino Acid." E-Journal of Chemistry 9, no. 4 (2012): 2446–52. http://dx.doi.org/10.1155/2012/826028.

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Thin layer chromatographic method has been developed for the separation of metal ions such as Cr(VI), Cr(III), As(III), Cd(II), Tl(III) and Hg(II) from their two, three and four component mixtures. The separations were performed on thin layer of silica gel ‘G’ using aqueous l-Alanine as mobile phase. The effect of concentration and pH of mobile phase on the Rfvalues of individual metal ions were studied and the optimum conditions for separation of metal ions from their mixture were determined.

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48

Saito, Akira, and Gregory R. Choppin. "Interaction of metal cations with heteropolytungstate ions SiW12O404- and P2W18O626-." Inorganic Chemistry 30, no. 24 (1991): 4563–66. http://dx.doi.org/10.1021/ic00024a020.

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Zhang, Yuzhe, Jiangfeng Li, Limin Qi, and Yurong Ma. "Investigation of the influence of cationic and anionic ions on the oriented dissolution of calcite." CrystEngComm 22, no. 32 (2020): 5316–22. http://dx.doi.org/10.1039/d0ce00760a.

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Cations (metal ions) have a more significant influence than anions on the oriented dissolution process of calcite and the metastable side faces and step edges of calcite micropyramids, probably due to the strong interaction between cations and CO<sub>3</sub><sup>2−</sup>.

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Anantanarayan, Ashok, and Thomas M. Fyles. "Polycarboxylate diaza crown ethers derived from R,R-(+)-tartaric acid: synthesis and complexation of metal ions." Canadian Journal of Chemistry 68, no. 8 (1990): 1338–51. http://dx.doi.org/10.1139/v90-206.

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The synthesis and complexation properties of polycarboxylate diaza crown ethers based on R,R-(+)-tartaric acid are described. Cesium carbonate mediated macrocyclization of a bis-tosylamide precursor with a bis-tosylate precursor provided the protected crown ethers. Photochemical deprotection of the tosylamides and hydrolysis of the carboxamides yielded dicarboxylic and tetracarboxylic acid derivatives of 1,10-diaza-18-crown-6. N-Methylenecarboxylate (N-acetate) derivatives were prepared by N-alkylation with bromoacetic acid. The synthetic and purification procedures developed provide samples o

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