Статті в журналах: "Nickel atomic ions"

1

Mahmud, H. N. M. Ekramul, Samira Hosseini, and Rosiyah Binti Yahya. "Removal of Nickel Ions from Aqueous Solution by Polypyrrole Conducting Polymer." Key Engineering Materials 594-595 (December 2013): 793–97. http://dx.doi.org/10.4028/www.scientific.net/kem.594-595.793.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Polypyrrole (PPy) conducting polymer prepared by chemical oxidation method using FeCl3.6H2O as an oxidant has exhibited 100% adsorption efficiency for the removal of nickel ions from aqueous solution. At pH 7, 100% nickel absorption was found by the prepared polypyrrole as measured by atomic absorption spectrophotometry. At both acidic and alkaline solutions, the adsorption efficiency of PPy was substantially lowered. The effects of pH, the initial concentration of nickel stock solution and the contact time on the uptake of nickel ions were also investigated. With the variation of initial concentration from 1-5 ppm, the initial concentration of 1 ppm nickel has been found to be adsorbed fully (100%) by the prepared polypyrrole. The contact time of 8 hours has been found to be the highest effective contact hours as beyond this there was no adsorption effect. The FTIR results confirmed the presence of nickel ions in the polymer matrix after adsorption.

2

Salem, Hesham, Khadiga Kelani, and Abdalla Shalaby. "Utility of Nickel for Atomic Absorption Spectrophotometric Determination of Selected Acidic Drugs." Scientia Pharmaceutica 69, no. 2 (June 30, 2001): 189–201. http://dx.doi.org/10.3797/scipharm.aut-01-20.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A simple and accurate method is described for the quantitative determination of flufenamic acid, mefenamic acid, tranexamic acid, furosemide, diclofenac sodium and thiaprofenic acid by precipitation reactions with nickel(II) followed by direct determination of the ions in the precipitate or indirect determination of the ions in the filtrate by atomic absorption spectroscopy. Statistical analysis of the results compared to assays used in pharmacopeas and the Amax. methods revealed equal precision and accuracy. Furthermore the assays were also applied for the determination of these drugs in pharmaceutical preparations.

3

Shah, Ambreen, Fayyaz Ahmed Keerio, Saima Qayyum Memon, and Ghulam Zuhra Memon. "Cloud Point Extraction for the Determination of Different Metal Ions by Using Bis(2-Acetyl Pyridine 4-Phenyl 3-Thiosemicarbazone) as Complexing Reagent." Pakistan Journal of Scientific & Industrial Research Series A: Physical Sciences 62, no. 2 (August 9, 2019): 76–81. http://dx.doi.org/10.52763/pjsir.phys.sci.62.2.2019.76.81.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A new method of cloud point extraction was determined for preconcentration and determination of different metal ions like copper(II), nickel(II) and cobalt(II) ions. The complexation has been done by bis(2-acetyl pyridine 4-phenyl 3-thiosemicarbazone) (APPT) using sodium dodecyl sulphate (SDS) as surfactant. Metal ions are extracted into the phase rich in SDS after centrifugation. Initially, micellar phase was dissolved in 10 mL of deionized water then acidified with 0.5 mol/L HNO3, enhanced the surfactant- rich phase and analyzed by flame atomic absorption spectrometry (FAAS). The effects of pH, the concen- trations of metal ions and chelating agent (APPT), volume of surfactant (SDS), equilibration temperature and time were studied on CPE. The preconcentration factor obtained was 25 and the limits of detection(DL) obtained for cobalt(II), nickel(II) and copper(II) were 1.5, 1.7 and 2.4 ng/mL, respectively. This method of preconcentration was effectively useful for the determination of cobalt(II), nickel(II) and copper(II) in water samples.

4

Soylak, Mustafa, Ayse Aydin, and Nebiye Kizil. "Multi-Element Preconcentration/Separation of Some Metal Ions in Environmental Samples by Using Co-precipitation." Journal of AOAC INTERNATIONAL 99, no. 1 (January 1, 2016): 273–78. http://dx.doi.org/10.5740/jaoacint.11-0214.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract A preconcentration/separation system for cadmium(II), nickel(II), copper(II), lead(II), iron(II), cobalt(II), and manganese(II) ions has been established prior to their atomic absorption spectrometric determinations. The procedure is based on the co-precipitation of these ions by the aid of a praseodymium hydroxide (Pr(OH)3) precipitate. The precipitate was dissolved in 0.5 mL of concentrated HNO3, and made up to 10.0 mL with water. The analytes were determined by a flame atomic absorption spectrometer. The effects of analytical parameters including pH, amounts of praseodymium as carrier element, sample volume, etc. on the recoveries of heavy metals were investigated. The effects of matrix ions were also examined. The limits of detection for analyte ions were found in the range between 0.7–5.2 μg/L. The validation of this present procedure was verified by the analysis of certified reference materials, TMDA-54.4 (fortified water) and NIST 1570a (spinach leaves). The proposed co-precipitation procedure was applied for the determination of cadmium(II), nickel(II), copper(II), lead(II), iron(II), cobalt(II), and manganese(II) ions in various environmental water samples.

5

Wang, L. J., K. Rinn, and D. C. Gregory. "Electron impact ionisation of nickel ions." Journal of Physics B: Atomic, Molecular and Optical Physics 21, no. 11 (June 14, 1988): 2117–28. http://dx.doi.org/10.1088/0953-4075/21/11/024.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Mohammadi, S., D. Afzali, and D. Pourtalebi. "Flame atomic absorption spectrometric determination of trace amounts of lead, cadmium and nickel in different matrixes after solid phase extraction on modified multiwalled carbon nanotubes." Open Chemistry 8, no. 3 (June 1, 2010): 662–68. http://dx.doi.org/10.2478/s11532-010-0029-8.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractThe potential of modified multiwalled carbon nanotubes (a solid-phase extraction sorbent), for the simultaneous separation and preconcentration of lead, cadmium and nickel; has been investigated. Lead, cadmium and nickel, were adsorbed quantitatively; on modified multiwalled carbon nanotubes (in the pH range of 2–4). Parameters influencing, the simultaneous preconcentration of Pb(II), Ni(II) and Cd(II) ions (such as pH of the sample, sample and eluent flow rate, type and volume of elution solution and interfering ions), have been examined and optimized. Under the optimum experimental conditions, the detection limits of this method. for Pb(II), Ni(II) and Cd(II) ions, were 0.32, 0.17 and 0.04 ng mL−1 in original solution, respectively. Seven replicate determinations, of a mixture of 2.0 μg mL−1 lead and nickel, and 1.0 μg mL−1 cadmium; gave a mean absorbance of 0.074, 0.151 and 0.310, with relative standard deviation 1.7%, 1.5% and 1.2%, respectively. The method has been applied, to the determination of trace amounts of lead, cadmium and nickel; in biological and water samples, with satisfactory results.

7

Shinoda, Kozo, Eiichiro Matsubara, Masatoshi Saito, Yoshio Waseda, Tetsuji Hirato, and Yasuhiro Awakura. "Structural Study of Poly-Molybdate Ions in Acid Mo-Ni Aqueous Solutions." Zeitschrift für Naturforschung A 52, no. 12 (December 1, 1997): 855–62. http://dx.doi.org/10.1515/zna-1997-1204.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The atomic structure of poly-molybdate ions formed in acid Ni-Mo aqueous solutions has been determined by applying anomalous X-ray scattering (AXS) and EXAFS methods. In a solution containing only molybdenum ions, we found only a poly-molybdate ion consisting of seven edgesharing MoO6 octahedra. In a solution containing both Mo and Ni ions, there exists another polymolybdate ion consisting of 6 edge-sharing MoO6 surrounding an Ni ion. The total coordination number of Mo and Ni ions around a molybdenum ion is reduced by half when introducing citric ions into the Ni and Mo solution. This indicates that the large poly-molybdate ion is decomposed to smaller molybdate ions when forming citric complexes. Since molybdenum-nickel alloys can not be electrodeposited from solutions without citric ions, we propose a view that the structural change of the poly-molybdate ions in the solutions is closely related with the mechanism of induced codeposition of molybdenum and nickel alloy. The results of small-angle X-ray scattering (SAXS) measurements also support this conclusion.

8

Rong, Wen, Sarah Stepan, and Rodney D. L. Smith. "Evidence of Variations in Atomic Distribution in Disordered Mixed Metal Hydroxides." MRS Advances 4, no. 33-34 (2019): 1843–50. http://dx.doi.org/10.1557/adv.2019.325.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

ABSTRACTNumerous fabrication protocols are known to yield transition metal oxides with structures related to layered double hydroxides, but the effect of fabrication protocol on the uniformity of mixed-metal compositions remain largely unexplored. We have analysed the apparent solubility limits and the structural implications of iron ions in nickel hydroxide lattices for materials prepared by four different fabrication protocols. Opposing shifts in the (100) and (001) reflection in powder X-ray diffraction results revealed a contraction of the nickel lattice upon successful incorporation of iron, with Ni-M distances exhibiting an apparently linear decrease with respect to iron content. This feature revealed the amount of iron incorporated into nickel-based materials to be dependent on fabrication protocol, varying from apparently negligible concentrations to over fifty atomic percent. The dependency of structure on fabrication protocols provides a handle to improve fundamental understanding of catalytically relevant coordination environments.

9

Zhang, Dong. "Pre-Concentration Capability for Trace Heavy Metal Ions with Manual-Controlled Injection Porous Nano-Barium-Strontium Titanate Microspheres Enricher." Advanced Materials Research 433-440 (January 2012): 689–92. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.689.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The micro-column packed with porous nano-barium- strontium titanate microspheres, joining with injector, a new manual-controlled injection porous nano-barium- strontium titanate microspheres enricher (PBSTME) was prepared. The enrichment capability of the PBSTME for the heavy metal ions, such as zinc, nickel, copper, manganese, cobalt and silver was investigated. The results showed that all the heavy metals studied could be quantitatively retained by the PBSTME in the pH range of 5–8, and then eluted completely with 2 mol•L-1 HNO3. The detection limits of this method for zinc, nickel, copper, manganese, cobalt and silver ions were 0.028 μg•L-1, 0.2μg•L-1, 0.031 μg•L-1, 0.022 μg•L-1, 0.057μg•L-1 and 0.039 μg•L-1 with an enrichment factor of 50, respectively. A new method has been developed for the determination of trace heavy metal ions based on pre-concentration with a PBSTME prior to their determination by flame atomic absorption spectrometry. The method has been applied to the simultaneous determination of trace amounts of zinc, nickel, copper, manganese, cobalt and silver ions in water sample with satisfactory results.

10

Manjith, CM, Srinivas Kumar Karnam, and A. Naveen Reddy. "Comparison of Metal Ion Release from Different Bracket Archwire Combinations: An in vitro Study." Journal of Contemporary Dental Practice 13, no. 3 (2012): 376–81. http://dx.doi.org/10.5005/jp-journals-10024-1154.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

ABSTRACT Aim The metal ion released from the orthodontic appliance may cause allergic reactions particularly nickel and chromium ions. Hence, this study was undertaken to determine the amount of nickel, chromium, copper, cobalt and iron ions released from simulated orthodontic appliance made of new archwires and brackets. Materials and methods Sixty sets of new archwire, band material, brackets and ligature wires were prepared simulating fixed orthodontic appliance. These sets were divided into four groups of fifteen samples each. Group 1: Stainless steel rectangular archwires. Group 2: Rectangular NiTi archwires. Group 3: Rectangular copper NiTi archwires. Group 4: Rectangular elgiloy archwires. These appliances were immersed in 50 ml of artificial saliva solution and stored in polypropylene bottles in the incubator to simulate oral conditions. After 90 days the solution were tested for nickel, chromium, copper, cobalt and iron ions using atomic absorption spectrophotometer. Results Results showed that high levels of nickel ions were released from all four groups, compared to all other ions, followed by release of iron ion levels. There is no significant difference in the levels of all metal ions released in the different groups. Conclusion The study confirms that the use of newer brackets and newer archwires confirms the negligible release of metal ions from the orthodontic appliance. Clinical significance The measurable amount of metals, released from orthodontic appliances in artificial saliva, was significantly below the average dietary intake and did not reach toxic concentrations. How to cite this article Karnam SK, Reddy AN, Manjith CM. Comparison of Metal Ion Release from Different Bracket Archwire Combinations: An in vitro Study. J Contemp Dent Pract 2012;13(3):376-381.

11

Motakef kazemi, Negar. "Zinc based metal–organic framework for nickel adsorption in water and wastewater samples by ultrasound assisted-dispersive-micro solid phase extraction coupled to electrothermal atomic absorption spectrometry." Analytical Methods in Environmental Chemistry Journal 3, no. 04 (December 29, 2020): 5–16. http://dx.doi.org/10.24200/amecj.v3.i04.123.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

In this research, Zn2(BDC)2(DABCO) metal–organic framework (MOF) as a solid phase was used for separation and preconcentration toxic nickel ions (Ni) from water samples by ultrasound assisted-dispersive-micro solid phase extraction coupled to electrothermal atomic absorption spectrometry (USA-D-μ-SPE/ET-AAS). The MOF nanostructure was characterized by field emission-scanning electron microscope (FE-SEM) and transmission electron microscopey (TEM) for presentation of morphology and size of MOF synthesis. By procedure, 25 mg of Zn2(BDC)2(DABCO) as MOF adsorbent was added to 25 mL of water samples and then, Ni ions chemically adsorbed based on dative bonding of nitrogen in DABCO (1,4-diazabicyclo [2.2. 2]octane); N2(C2H4)3) at pH=8. The adsorbent was separated from liquid phase by syringe cellulose acetate filters (SCAF, 0.2 μm) and Ni ions back extracted from MOF adsorbent before determined by ET-AAS. The maximum recovery of MOF for nickel ions as a physically and chemically adsorption was obtained 34.6% and 98.8% at pH=3 and 8, respectively.

12

Nafai, H., G. Lamzougui, A. Bouhaouss, and R. Bchitou. "Study of physico-chemical characteristics of nickel insertion in phosphogypsum." JOURNAL OF ADVANCES IN CHEMISTRY 12, no. 6 (November 13, 2016): 4134–38. http://dx.doi.org/10.24297/jac.v12i6.4338.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The main purpose of this work is study the influence of the insertion metal ions Ni (II) in the phosphogypsum produced by sulfuric acid attack of tricalcium phosphate. Indeed, the maximum content of heavy metals calcium sulfate that can absorb was determined. The added ions are (NiCl2, 6H2O) with mass concentrations ranging from 5% to 50%. The samples prepared were characterized by various methods, such as X-ray diffraction (XRD), infrared spectroscopy and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results of this study showed that the limit of insertion of metal cations in calcium sulfate is limited to 30% for nickel.

13

Denisova, Tatiana A., Lidia G. Maksimova, Dina G. Kellerman, M. A. Melkozerova, Elena V. Zabolotskaya, Valentin Yakovlevich Mitrofanov, and G. A. Dorogina. "Magnetic Properties of Intercalated Zinc Hexacyanoferrate (II)." Solid State Phenomena 168-169 (December 2010): 169–72. http://dx.doi.org/10.4028/www.scientific.net/ssp.168-169.169.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The results of magnetic behavior study of nickel ions, which were introduced into Zn2Fe(CN)6∙5.5H2O with channel structure, are presented. It was shown that nickel cations replace a part of Zn2+ ions or locate in the channels of lattice via the molecular mechanism sorption. It is shown that the magnetic moments μNi of the sorption products strongly depend on the content of Ni2+ ions. The values of μNi of the samples with Ni/Fe(CN)6=2.26 and 2.86 are great ~ 3.9 and 4.4 μB respectively and close to the value typical of free Ni2+ ions μ =4.47μB.

14

Matos de Souza, Rodrigo, and Luciane Macedo de Menezes. "Nickel, Chromium and Iron Levels in the Saliva of Patients with Simulated Fixed Orthodontic Appliances." Angle Orthodontist 78, no. 2 (March 1, 2008): 345–50. http://dx.doi.org/10.2319/111806-466.1.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract Objective: To assess the in vivo release of nickel, chromium, and iron ions into saliva by different metallic brackets. Materials and Methods: Thirty volunteers wore removable appliances with bonded brackets and were divided according to the brand of brackets: group A, 3M/Unitek (AISI 303); group B, American Orthodontics (AISI 316L); and group C, Dentaurum (AISI 316L). The appliances were worn for 60 days, and saliva samples were collected at the following time points: T1, before placement of the appliance; T2, after 10 minutes; T3, 24 hours; T4, 7 days; T5, 30 days; and T6, 60 days after insertion of the removable appliance. Saliva samples were analyzed for nickel, chromium, and iron by atomic absorption spectrophotometry. Statistical analysis was performed by nonparametric tests (Friedman, Mann-Whitney, Kruskal-Wallis). Results: Saliva evaluation revealed a large variation in concentration of these ions between individuals. The results also appeared to indicate an increase in nickel and chromium ions immediately after placement of the appliance (T2), but this was statistically significant only for groups B and C. There was no increase in iron levels. A tendency for increases in nickel and chromium concentrations was verified immediately after placement of the appliance, but these values are probably reduced because of biofilm formation regardless of the bracket used. Conclusion: Nickel and chromium ion concentrations increased immediately after placement of the appliance in the mouth for all study groups. There were no significant differences in the nickel, chromium, and iron levels released by the three groups of appliances at all study periods.

15

Daido, H., S. Ninomiya, T. Imani, Y. Okaichi, M. Takagi, R. Kodama, H. Takabe, et al. "Atomic Number Scaling of the Nickel-Like Soft X-Ray Lasers." International Journal of Modern Physics B 11, no. 08 (March 30, 1997): 945–90. http://dx.doi.org/10.1142/s0217979297000496.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

We report the review of the experimental results obtained at the Institute of Laser Engineering, Osaka University, of the soft X-ray lasing in various Ni-like ions whose atomic numbers range from 47(Ag) to 66(Dy). The lasing wavelengths are between 14 nm and 5 nm. X-ray lasing in these materials were obtained when the plasma profiles were properly controlled in time and space by irradiation of curved slab targets with multiple laser pulses. We also describe the original work of the atomic physics calculations which provide the transition energies, transition probabilities and other atomic constants for Ni-like ion species whose atomic numbers range from 36 to 92 calculated with GRASP code (multi-configuration Dirac Fock code) and YODA code (relativistic distorted wave code). Based on these atomic constants, we have calculated the kinetics of the population inversion with a simplified rate equation model in conjunction with a one-dimensional hydrodynamic code to find out the desired pumping conditions. We show a possibility for significant improvement in the pumping efficiency with the use of a picosecond laser irradiating a properly configured preformed plasma. Finally, a simplified estimation of the pumping efficiency is described based on the atomic constants and plasma physics issues.

16

TANG, DONGYAN, and JI LI. "PREPARATION OF NICKEL ULTRATHIN FILM BY THE LANGMUIR–BLODGETT TECHNIQUE AND CHEMICAL REDUCTION." Surface Review and Letters 16, no. 05 (October 2009): 663–68. http://dx.doi.org/10.1142/s0218625x0901313x.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The nickel ion containing Langmuir–Blodgett (LB) multilayer was prepared by transferring first dissolving nickel acetate and the solution was poured into a subphase of ultrapure water and stearic acid-chloroform. The resultant mixture was then spread onto a hydrophilic water or glass plate. Then the multilayer was converted into nickel ultrathin film after chemical reduction by sodium borohydride. The optimized parameters for monolayer formation, such as concentration of subphase, pH value, barrier speed and standing time, were determined by the measurement of the surface pressure–surface area (Π–A) isotherms. The expended areas after deposition with nickel ions inferred the interaction of stearic acid with nickel ion during the formation of monolayer at air–water interface. The optimized parameters for multilayer deposition, such as surface pressure and dipping speed were determined by the measurement of the transfer coefficient. The Fourier transform infrared spectroscopy (FTIR) was used to investigate the interactions of nickel ions with stearic acid at air–water interface and in nickel ion/stearic acid LB film, as well as the metal transformations of nickel ion in ultrathin film. The disappearance of peak at 1689 cm-1 verified the interactions between stearic acid and nickel ion. The further reduction made the organic phase dissolve and remove from the multilayer mostly. The surface morphologies of the LB multilayer and ultrathin film after reduction were detected by atomic force microscopy (AFM). A uniform and flat surface of nickel ultrathin film within nanometer ranges were obtained after reduction. The particle sizes of nickel were approximately 50 nm.

17

MAHSHID, S. S., and A. DOLATI. "A STUDY ON THE ELECTRODEPOSITION MECHANISM OF COBALT-NICKEL/COPPER MULTILAYER FROM SULFATE SOLUTION." International Journal of Modern Physics B 22, no. 18n19 (July 30, 2008): 3046–59. http://dx.doi.org/10.1142/s0217979208047912.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The cobalt-nickel/copper multilayer films were prepared by electrodeposition process in sulfate solution using a three electrode cell. Cyclic voltammetry and double chronoampermetry techniques were utilized to characterize the multilayer system and to obtain the nucleation and growth mechanism. The cyclic voltammograms determined the reduction potential range of the three components and also clearly emphasized that electrodeposition of cobalt-nickel alloy was controlled by a kinetic process, while copper ions were reduced with diffusion-controlled mechanism. These results were confirmed with those which were extracted from the chronoampermetry curves. In addition, the current transients revealed that nucleation mechanism was a typical three-dimensional nucleation process. The Atomic Force Microscope images (AFM) of these multilayers also confirmed the three-dimensional nucleation mechanism. The compositional analysis of these multilayers was carried out by Atomic Absorption Spectroscopy (AAS) and X-ray Photoelectron Spectroscopy (XPS) methods. The bulk and surface compositional analysis both revealed that the amount of Copper component within the cobalt-nickel layers is less than 3%.

18

Radzyminska-Lenarcik, Elzbieta, and Malgorzata Ulewicz. "The use of the steric effect of the carrier molecule in the polymer inclusion membranes for the separation of cobalt(II), nickel(II), copper(II), and zinc(II) ions." Polish Journal of Chemical Technology 17, no. 2 (June 1, 2015): 51–56. http://dx.doi.org/10.1515/pjct-2015-0029.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract In this study, palladium-modified nickel foam substrate was applied to examine ethanol oxidation reaction (EOR) in 0.1 The transport of cobalt(II), nickel(II), copper(II), and zinc(II) ions from chloride solutions across polymer inclusion membranes (PIMs), which 1-heptylimidazole (1̲) or 1-heptyl-2-methylimidazole (2̲) or 1-heptyl-4-methylimidazole (3̲) as the ion carrier was reported. The steric effect for carriers 2̲and 3̲decreases the transport of all ions except Cu(II). The initial fl uxes of metal ions transport across PIMs with the 1̲- 2̲decrease in the sequence: Cu(II) > Zn(II) > Co(II) > Ni(II), whereas for 3 they were Cu(II) > Zn(II) > Ni(II) > Co(II). The highest recovery values were obtained for Cu(II), this being 99 and 85% for carrier 1̲and 2̲, respectively. In both membranes the degree of deposition of the Zn(II) ions was comparable. Zn(II), Co(II) and Cd(II) ions, which form complexes with coordination numbers 4 and 6, are more easily recovered with the use of carriers 2̲and 3̲. Ni(II) ions, which form complexes with coordination number 6 only, practically remain in the feeding phase. PIMs with alkylimidazoles were characterized by non-contact atomic force microscopy.

19

Cherkani-Hassani, S., P. Defrance, and E. M. Oualim. "Electron Impact Ionization of Nickel Multiply-Charged Ions." Physica Scripta T80, B (1999): 292. http://dx.doi.org/10.1238/physica.topical.080a00292.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Wang, Mei-Ling, Guo-Qing Zhong, and Ling Chen. "Synthesis, Optical Characterization, and Thermal Decomposition of Complexes Based on Biuret Ligand." International Journal of Optics 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/5471818.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Four complexes were synthesized in methanol solution using nickel acetate or nickel chloride, manganese acetate, manganese chloride, and biuret as raw materials. The complexes were characterized by elemental analyses, UV, FTIR, Raman spectra, X-ray powder diffraction, and thermogravimetric analysis. The compositions of the complexes were [Ni(bi)2(H2O)2](Ac)2·H2O (1), [Ni(bi)2Cl2] (2), [Mn(bi)2(Ac)2]·1.5H2O (3), and [Mn(bi)2Cl2] (4) (bi = NH2CONHCONH2), respectively. In the complexes, every metal ion was coordinated by oxygen atoms or chlorine ions and even both. The nickel and manganese ions were all hexacoordinated. The thermal decomposition processes of the complexes under air included the loss of water molecule, the pyrolysis of ligands, and the decomposition of inorganic salts, and the final residues were nickel oxide and manganese oxide, respectively.

21

Li, Zhanyong, Aaron W. Peters, Jian Liu, Xuan Zhang, Neil M. Schweitzer, Joseph T. Hupp, and Omar K. Farha. "Size effect of the active sites in UiO-66-supported nickel catalysts synthesized via atomic layer deposition for ethylene hydrogenation." Inorganic Chemistry Frontiers 4, no. 5 (2017): 820–24. http://dx.doi.org/10.1039/c7qi00056a.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

22

Sorouraddin, Saeed Mohammad, and Saeed Nouri. "Simultaneous temperature-assisted dispersive liquid–liquid microextraction of cobalt, copper, nickel and zinc ions from high-volume water samples and determination by graphite furnace atomic absorption spectrometry." Analytical Methods 8, no. 6 (2016): 1396–404. http://dx.doi.org/10.1039/c5ay03288a.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A rapid, efficient, and reliable sample preparation method based on temperature-assisted dispersive liquid–liquid microextraction was developed for simultaneous extraction of cobalt, copper, nickel, and zinc ions at a low level from high volume water samples.

23

Zheng, Hu-Zhi, Li Liu, Zhu-Jun Zhang, Yu-Ming Huang, Dong-Bo Zhou, Jian-Yu Hao, Yi-Hui Lu, and Su-Ming Chen. "Quenching effect of nickel ions on fluorescent gold nanoparticles." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 71, no. 5 (January 2009): 1795–98. http://dx.doi.org/10.1016/j.saa.2008.06.040.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

24

Wang, Shu-Xing, Zhong-Kui Huang, Wei-Qiang Wen, Chong-Yang Chen, Stefan Schippers, Xin Xu, Shahid Sardar, et al. "Dielectronic recombination rate coefficients of fluorine-like nickel." Astronomy & Astrophysics 627 (July 2019): A171. http://dx.doi.org/10.1051/0004-6361/201935648.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Electron-ion recombination rate coefficients for fluorine-like nickel ions have been measured by employing the merged-beam technique at the cooler storage ring CSRm at the Institute of Modern Physics in Lanzhou, China. The measured spectrum covers the energy range of 0–160 eV, including all the dielectronic recombination (DR) resonances associated with ΔN = 0 core excitations. The DR cross sections in this energy range were calculated by a relativistic configuration interaction method using the flexible atomic code (FAC). Radiative recombination (RR) cross sections were obtained from a modified version of the semi-classical Bethe & Salpeter (1957, Quantum Mechanics of One- and Two-Electron 56 Systems (Springer)) formula for hydrogenic ions. The comparison between the measurement and the calculation shows that the present theoretical model still needs to be improved at low collision energies. Temperature dependent plasma recombination rate coefficients were derived from the measured DR rate coefficients in the temperature range of 103–108 K and compared with the presently calculated result as well as previous available data in the literature. The experimentally derived data agree well with the theoretical calculations for temperatures where Ni19+ ions form in collisionally ionized plasmas. At lower temperatures typical for photo-ionized plasmas, discrepancies are found beyond the experimental uncertainty, which can be attributed to the disagreement between the measurement and the calculation of the low-lying DR resonances. The present experimental result benchmarks the plasma DR rate coefficients, in particular for temperatures below 105 K where the ΔN = 0 DR resonances dominate.

25

Rehman, R., and T. Tanveer. "Spectrophotometric determination of significant minerals in milk samples found in Lahore (Pakistan) for ensuring food safety." Bulgarian Chemical Communications 51, no. 2 (2019): 206–11. http://dx.doi.org/10.34049/bcc.51.2.4833.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

This work was carried out for determination of essential and toxic metals ions in different milk powder samples commonly found in Lahore (Pakistan). Samples were collected from local markets and after dry ashing, they were dissolved in 2M nitric acid for complete mineralization. Then the concentration of metal ions was determined by flame photometry and atomic absorption spectrometry. The concentration levels of cadmium, lead and nickel were found to be below detection limits in all samples, whereas the maximum values of sodium, potassium, calcium, magnesium, iron, and zinc were 48.55, 0.96, 4.94 mg/g, and 768, 4.12 and 3.02 μg/g respectively. Minimum amounts of these metal ions were: 3.69, 0.07, 0.85 mg/g and 214, 0.21, 1.02 μg/g, respectively. The amounts of all metal ions were found to be within safe limits as recommended by WHO.

26

Narmada, Ida Bagus, Natalya Tantri Sudarno, Achmad Sjafei, and Yuli Setiyorini. "The influence of artificial salivary pH on nickel ion release and the surface morphology of stainless steel bracket-nickel-titanium archwire combinations." Dental Journal (Majalah Kedokteran Gigi) 50, no. 2 (June 30, 2017): 80. http://dx.doi.org/10.20473/j.djmkg.v50.i2.p80-85.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Background: In the oral cavity, orthodontic appliances come into contact with saliva which may cause corrosion capable of changing their surface morphology due to the release of metal ions. Surface roughness can influence the effectiveness of tooth movement. One of the ions possibly released when body fluid comes into contact with brackets and archwire is nickel ion (Ni). Ni, one of the most popular components of orthodontic appliances, is, however, a toxic element that could potentially increase the likelihood of health problems such as allergic responses during treatment. Purpose: The purpose of this study was to investigate the effect of different artificial salivary pH on the ions released and the surface morphology of stainless steel (SS) brackets-nickel-titanium (NiTi) and archwire combinations. Methods: Brackets and archwires were analyzed by an Energy Dispersive X-Ray Detector System (EDX) to determine their composition, while NiTi archwire compound was examined by means of X-ray Diffraction (XRD). The immersion test was performed at artificial salivary pH levels of 4.2; 6.5; and 7.6 at 37°C for 28 days. Ni ion release measurement was performed using an Atomic Absorption Spectroscopy (AAS). Surface morphology was analyzed by means of a Scanning Electron Microscopy (SEM). Results: The chemical composition of all orthodontic appliances contained Ni element. In addition, XRD was depicted phases not only NiTi but also Ni, Titanium, Silicon and Zinc Oleate. The immersion test showed that the highest release of Ni ions occured at a pH of 4.2, with no significant difference at various levels of pH (p=.092). There were surface morphology changes in the orthodontic appliances. It was revealed that at a pH of 4.2, the surfaces of orthodontic appliances become unhomogenous and rough compared to those at other pH concentrations. Conclusion: The reduction of pH in the artificial saliva increases the amount of released Ni ions, as well as causing changes to the surface morphology of brackets and archwires.

27

Setiarso, Pirim, and Selvi Purwanti N. "THE EXTRACTION OF NICKEL(II) AND COPPER(II) USING LIQUID MEMBRANE EMULSION TECHNIQUE." Indonesian Journal of Chemistry 6, no. 2 (June 14, 2010): 186–88. http://dx.doi.org/10.22146/ijc.21758.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Research on the extraction of Nickel(II) and Copper(II) using liquid membrane emulsion technique has been conducted. The purpose of this research is to know the influence of pH, extraction time and presence of competed metals (Ni2+ in Cu2+ and vice versa) toward the membrane extraction capability. In this research, 84 mL of Ni2+ and Cu2+ with concentration of 100 ppm, each, was extracted using pH variation (4.0, 4.5, 5.0, 5.5, 6.0). The optimum pH will be used to obtain the time of equilibrium and influence of the competed ions. Time variations (15, 20, 25, 30, 35 minute) were used with the concentration of the competed ions of 20, 40, 60, 80, 100 ppm. The percentage of ions extracted was analyzed by Atomic Absorption Spectrometry. The result shows that the optimum pH was 5.0 for extracting 79.3137 % Cu2+ and 50.3448 % Ni2+. Time of equilibrium was 30 minutes for extracting 85.4117 % Cu2+ and 53.7691 % Ni2+. The presence of Ni2+ influenced Cu2+ extracted and vice versa. Keywords: Extraction, liquid membrane emulsion

28

Porojan, Liliana, Mihaela Birdeanu, and Sorin Porojan. "Multidisciplinary Approach on the Corrosion Behavior of Welded Nickel-free and Nickel-containing Stainless Steel Orthodontic Wires." Revista de Chimie 70, no. 7 (August 15, 2019): 2447–51. http://dx.doi.org/10.37358/rc.19.7.7359.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The oral environment is responsible to the degradation of metal wires, with consequent release of metal ions in the oral cavity during corrosion, and welded joints are known as areas that are particularly susceptible to corrosion. The aim of the study was to achieve the corrosion behavior of welded Ni-free and Ni-containing stainless steel (SS) orthodontic wires. The morphology and the topography of the laser welded samples were investigated by scanning electron microscopy and atomic force microscopy. The electrochemical measurements calculated the values for corrosion potential, corrosion current and corrosion rate, for different pH values. Immersion in acidic solution had minimal effect on the corrosion on the joint regions. Ni-free SS wires proved to have a better corrosion resistance, improved by laser welding. Ni-containing SS wires are positive influenced by laser welding, relative to the corrosion behavior.

29

Petrovic, S., N. Bundaleski, M. Radovic, Z. Ristic, G. Gligoric, D. Perusko, and S. Zec. "Structure and surface composition of NiCr sputtered thin films." Science of Sintering 38, no. 2 (2006): 155–60. http://dx.doi.org/10.2298/sos0602155p.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Thin films of nichrome were deposited by d.c. sputtering of a target (80%Ni 20%Cr w.t) by Ar+ions at a working pressure of 10-1 Pa and at room temperature. The phase composition and grain size were studied by X-ray Diffraction (XRD), while the surface chemical composition was determined by Low Energy Ion Scattering (LEIS). Analysis of phase composition showed that the NiCr thin films were a solid solution of chromium in a nickel matrix with increased nickel lattice parameters. LEIS analysis showed the presence of Ni Cr and O in the first atomic layer. There is a strong suspicion that surface passivation occurred by forming Cr2O3 oxide at the surface.

30

Vemula, Praveen Kumar, R. Rox Anderson, and Jeffrey M. Karp. "Nanoparticles reduce nickel allergy by capturing metal ions." Nature Nanotechnology 6, no. 5 (April 3, 2011): 291–95. http://dx.doi.org/10.1038/nnano.2011.37.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Puente Torres, Jeamichel, Harold Crespo Sariol, Thayset Mariño Peacok, Jan Yperman, Peter Adriaensens, Robert Carleer, and Ángel Brito Sauvanell. "X-ray Absorption (XRA): A New Technique for the Characterization of Granular Activated Carbons." Materials 14, no. 1 (December 28, 2020): 91. http://dx.doi.org/10.3390/ma14010091.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The X-ray absorption (XRA) method using digital image processing techniques is a reliable technique to determine the exhaustion degree of granular activated carbons (GACs). Using an innovative digital image processing technique, the identification of individual adsorbed molecules or ions in a GAC was possible. Adsorption isotherm models (Langmuir and Freundlich) were used to simulate the adsorption equilibrium data of Methylene Blue (MB), nickel, cobalt and iodine. Freundlich equation was found to have the highest value of R2 compared with Langmuir. The identification of distinctive patterns applying XRA for different adsorbed ions and molecules onto GAC was explored. It is demonstrated that unique XRA configurations for each adsorbed ion or molecule are found, as well as a proportional relationship between its incident energy (needed to achieve maximum photon attenuation) and the (effective) atomic number, the adsorbate mass and the molar or atomic mass of adsorbed molecule or ion. XRA method in combination with image histogram modifications was used to obtain a digital signature of adsorbed ions/molecules, giving distinct GSI values for each one in the used energy range. Probabilistic models prove that XRA results are within relationships between effective atomic number and photonic interaction probability, reinforcing the potentialities of XRA for monitoring (multi-)ion and/or molecule combinations on GAC using advanced digital image processing techniques. It was proved that the proposed approach could assess different adsorbed ions/molecules onto GACs in water purification systems.

32

Fakhraie, Saeed, та Ali Ebrahimi. "Facile synthesis of a modiﬁed HF-free MIL-101(Cr) nanoadsorbent for extraction nickel in water and wastewater samples". Analytical Methods in Environmental Chemistry Journal 3, № 02 (28 червня 2020): 59–73. http://dx.doi.org/10.24200/amecj.v3.i02.103.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A novel sorbent based on MIL-101(Cr) nanoadsorbent as MOF structure was used for nickel extraction from water and wastewater samples. In this study, 30 mg of MIL-101(Cr) nanoadsorbent dispersed in 50 mL of water or wastewater samples, after sonication and adjusting pH =8.5, the nickel ions was extracted by carboxyl groups of terephthalic acid (MOF-(C6H4 (COO)-2…. Ni2+) by dispersive suspension micro solid phase extraction (DS-μ-SPE).The MOF was separated from liquid phase with filter membrane (0.2 μm), eluted with 0.5 mL of nitric acid as back-extraction solution and finally, the nickel concentration in eluent determined by atom trap-flame atomic absorption spectrometry (AT-FAAS) after dilution with DW up to 1 mL.The LOD, the linear range and preconcentration factor were achieved 1.5 µg L−1, 5-160 µg L−1 and 49.7, respectively.The absorption capacity of MOF for nickel was obtained 136.8 mg g-1.The results of procedure were validated by spiking of samples and ET-AAS analyzer.

33

Taher, Mohammad Ali, Lida Mazaheri, Hamid Ashkenani, Alireza Mohadesi, and Daryoush Afzali. "Determination of Nickel in Water, Food, and Biological Samples by Electrothermal Atomic Absorption Spectrometry After Preconcentration on Modified Carbon Nanotubes." Journal of AOAC INTERNATIONAL 97, no. 1 (January 1, 2014): 225–31. http://dx.doi.org/10.5740/jaoacint.12-327.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract A new and sensitive SPE method using modified carbon nanotubes for extraction and preconcentration, and electrothermal atomic absorption spectrometric determination of nickel (Ni) in real samples at ng/L levels was investigated. First, multiwalled carbon nanotubes were oxidized with concentrated HNO3, then modified with 2-(5-bormo-2-pyridylazo)-5-diethylaminophenol reagent. The adsorption was achieved quantitatively on a modified carbon nanotubes column in a pH range of 6.5 to 8.5; the adsorbed Ni(II) ions were then desorbed by passing 5.0 mL of 1 M HNO3. The effects of analytical parameters, including pHof the solution, eluent type and volume, samplevolume, flow rate of the eluent, and matrix ions, were investigated for optimization of the presented procedure. The enrichment factor was 180, and the LOD for Ni was 4.9 ng/L. The method was applied to the determination of Ni in water, food, and biological samples, and reproducible results wereobtained.

34

Zhu, Shan Shan, Fu Tao Hu, Dao Dong Pan, Wei Lian Xu, and Ning Gan. "Determination of Ultra Trace of Heavy Metals in Water by ICP-AES Based on Magnetic Enrichment." Advanced Materials Research 487 (March 2012): 658–62. http://dx.doi.org/10.4028/www.scientific.net/amr.487.658.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A new method has been established for the pre-enrichment of trace heavy metals(lead(II), cadmium(II), chromium(VI) and nickel(II)) by magnetic iron oxide(core) / zirconium dioxide(shell) and determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) in water samples. The factors affecting the separation and pre-enrichment of analytes such as amounts of magnetic iron oxide / zirconium dioxide, elution time and interfering ions were studied. The detection limits of the method (3σ) were 13.5ng/mL, 1.01ng/mL, 2.94ng/mL and 3.31mg/L respectively for lead(II), cadmium(II), chromium(VI) and nickel(II). The results showed that this method was simple, accurate, and sensitive which could be applied for the pre-enrichment, separation and determination of trace heavy metals in all kinds of water samples.

35

Amirkhanyan, Zohrab G., Claúdio M. R. Remédios, Yvonne P. Mascarenhas, and Sérgio L. Morelhão. "Analyzing structure factor phases in pure and doped single crystals by synchrotron X-ray Renninger scanning." Journal of Applied Crystallography 47, no. 1 (December 25, 2013): 160–65. http://dx.doi.org/10.1107/s1600576713028677.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

X-ray multiple diffraction has been applied to study the substitutional incorporation of Mg2+ions into NSH crystals (nickel sulfate hexahydrate, NiSO4·6H2O). Intensity profiles provide information on invariant phases, while angular positions of the multiple diffractions allow accurate determination of lattice parameters. By increasing the atomic disordering only of O2−sites in model structures of doped NSH, the sense and magnitude of induced phase shifts match those necessary to justify the observed changes in the intensity profiles. Causes of disordering and lattice parameter variation are discussed. Although the amount of extra oxygen disordering is relatively large with respect to the small difference in the ionic radii of the metallic ions, this disordering is beyond the resolution power achievable by analyzing diffracted intensities of isolated reflections, such as in standard crystallographic techniques.

36

Jendrzejewska, Izabela, Tomasz Goryczka, Karolina Kaczmarek, and Ewa Maciążek. "Polycrystalline Compounds Cd_1-xNi_xCr₂Se₄ Obtained by Ceramic Technology." Solid State Phenomena 130 (December 2007): 241–44. http://dx.doi.org/10.4028/www.scientific.net/ssp.130.241.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The polycrystalline compounds of the general formula Cd1-xNixCr2Se4 have been prepared by the ceramic method in closed silica tubes using CdSe, NiSe and Cr2Se3. The phase composition and structural data have been determined by X-ray diffraction. The observed symmetry is cubic, space group Fd 3m . Apart from spinel phases, other phases were observed: CdSe, NiSe2 and Cr5.6Se8. Depending on amount of nickel, nickel ions can occupy tetrahedral and octahedral sites.

37

Ghaedi, Mehrorang, Ardeshir Shokrollahi, Khodabakhsh Niknam, Ebrahim Niknam, and Mustafa Soylak. "Development of efficient method for preconcentration and determination of copper, nickel, zinc and iron ions in environmental samples by combination of cloud point extraction and flame atomic absorption spectrometry." Open Chemistry 7, no. 1 (March 1, 2009): 148–54. http://dx.doi.org/10.2478/s11532-008-0102-8.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractA cloud point extraction procedure for the preconcentration of copper, nickel, iron and zinc ions in various samples has been described. Analyte ions in aqueous phase are complexed with 3-((indolin-3-yl)(phenyl)methyl)indoline (IYPMI) and following centrifugation quantitatively extracted to the aqueous phase rich in Triton X-114. The surfactant-rich phase was dissolved in 2.0 mol L−1 HNO3 in methanol prior to metal content determination by flame atomic absorption spectrometry (FAAS). The effects of some parameters including, the concentrations of IYPMI, Triton X-114 and HNO3, bath temperature, centrifuge rate and time were investigated on the recoveries of analyte ions. At optimum conditions, the detection limits of (3 SDb m−1) of 1.6, 2.8, 2.1 and 1.1 ng mL−1 for Cu2+, Fe3+, Ni2+ and Zn2+ along with preconcentration factors of 30 and enrichment factor of 48, 39, 34 and 52 for Cu2+, Ni2+, Fe3+ and Zn2+ respectively, were obtained. The proposed cloud point extraction has been successfully applied for the determination of metal ions in real samples with complicated matrix such as biological, soil and blood samples with high efficiency.

38

Kolmachikhina, O. B., Y. A. Napolskikh, and K. A. Vakula. "Nickel Extraction from Poor Solutions by Sorption on Modified Coke." Solid State Phenomena 284 (October 2018): 785–89. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.785.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The principal coke modification possibility with butyl potassium xanthate was revealed. It was shown that the modified coke exhibits sorption properties with respect to nickel ions compared to untreated coke, traditionally used for melting. The influence degree of various factors on the sorption capacity of the modified coke was established.

39

Saracoglu, Sibel, Mustafa Soylak, Dilek Çabuk, Zeynep Topalak, and Yasemin Karagozlu. "Determination of Some Trace Elements in Food and Soil Samples by Atomic Absorption Spectrometry After Coprecipitation with Holmium Hydroxide." Journal of AOAC INTERNATIONAL 95, no. 3 (May 1, 2012): 892–96. http://dx.doi.org/10.5740/jaoacint.11-304.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract The determination of trace elements in food and soil samples by atomic absorption spectrometry was investigated. A coprecipitation procedure with holmium hydroxide was used for separation- preconcentration of trace elements. Trace amounts of copper(II), manganese(II), cobalt(II), nickel(II), chromium(III), iron(III), cadmium(II), and lead(II) ions were coprecipitated with holmium hydroxide in 2.0 M NaOH medium. The optimum conditions for the coprecipitation process were investigated for several commonly tested experimental parameters, such as amount of coprecipitant, effect of standing time, centrifugation rate and time, and sample volume. The precision, based on replicate analysis, was lower than 10% for the analytes. In order to verify the accuracy of the method, the certified reference materials BCR 141 R calcareous loam soil and CRM 025-050 soil were analyzed. The procedure was successfully applied for separation and preconcentration of the investigated ions in various food and soil samples. An amount of the solid samples was decomposed with 15 mL concentrated hydrochloric acid–concentrated nitric acid (3 + 1). The preconcentration procedure was then applied to the final solutions. The concentration of trace elements in samples was determined by atomic absorption spectrometry.

40

Ebrahimi, Bahram, Soleiman Bahar, and Seyde Elham Moedi. "Evaluation of Graphene as a Solid-Phase Extraction Sorbent for the Preconcentration and Determination of Trace Amounts of Nickel in Food Samples Prior to Flame Atomic Absorption Spectrometry." Journal of AOAC INTERNATIONAL 98, no. 3 (May 1, 2015): 822–27. http://dx.doi.org/10.5740/jaoacint.14-190.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract A sensitive and low cost SPE method for the extraction, preconcentration, and flame atomic absorption spectrometric determination of nickel at ng/mL levels is described. Parameters governing the extraction efficiency including pH of the solution, eluent type, sample volume, and matrix ions were investigated for optimization of the presented procedure. The enhancement factor was calculated as 96.5. The calibration curve was linear with R2 of 0.999 in the concentration range from 2 to 200 ng/mL. The RSD was 5.35% (n = 7), the LOD was 0.588 ng/mL, and relative recoveries from vegetable samples ranged between 99 and 109.5%.

41

Ghaedi, Mehrorang, Farshid Ahmadi, and Mustafa Soylak. "Simultaneous Preconcentration of Copper, Nickel, Cobalt and Lead Ions Prior to Their Flame Atomic Absorption Spectrometric Determination." Annali di Chimica 97, no. 5-6 (April 2007): 277–85. http://dx.doi.org/10.1002/adic.200790027.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

42

Ghaedi, Mehrorang, Farshid Ahmadi, and Ardeshir Shokrollahi. "Simultaneous preconcentration and determination of copper, nickel, cobalt and lead ions content by flame atomic absorption spectrometry." Journal of Hazardous Materials 142, no. 1-2 (April 2007): 272–78. http://dx.doi.org/10.1016/j.jhazmat.2006.08.012.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Mousavi, Hassan Zavvar, and Jalal Derakhshankhah. "Column Preconcentration and FAAS Determination of Heavy Metal Ions using Artemisia Siberi as an Adsorbent." Journal of AOAC INTERNATIONAL 97, no. 6 (November 1, 2014): 1707–12. http://dx.doi.org/10.5740/jaoacint.12-109.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract A new column procedure for the determination of trace amounts of cadmium (II), lead (II), nickel (II), zinc (II), and copper (II), which combines flame atomic absorption spectrometry is described. These metals were sorbed on Artemisia siberi herb as an adsorbent at pH 4.0 and eluted with 3 mL of 1.5 M HNO3. The influences of analytical parameters including pH, flow rate, sample volume, type of eluent, and effect of diverse salts and cations on the recoveries of analyte ions were studied. The developed procedure provides preconcentration factors of about 117. LODs were 0.2 (Cd), 0.4 (Cu), 0.2 (Ni), 0.6 (Zn), and 1.4 (Pb) μg/L. The present method was successfully applied to the determination of the above-mentioned ions in water samples from Semnan, Iran. Recoveries greater than 95% and RSDs below 10% were obtained.

44

Tahmasbi, Soodeh, Tahereh Sheikh, and Yasamin B. Hemmati. "Ion Release and Galvanic Corrosion of Different Orthodontic Brackets and Wires in Artificial Saliva." Journal of Contemporary Dental Practice 18, no. 3 (2017): 222–27. http://dx.doi.org/10.5005/jp-journals-10024-2021.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

ABSTRACT Introduction To investigate the galvanic corrosion of brackets manufactured by four different companies coupled with stainless steel (SS) or nickel–titanium (NiTi) wires in an artificial saliva solution. Materials and methods A total of 24 mandibular central incisor Roth brackets of four different manufacturers (American Orthodontics, Dentaurum, Shinye, ORJ) were used in this experimental study. These brackets were immersed in artificial saliva along with SS or NiTi orthodontic wires (0.016”, round) for 28 days. The electric potential difference of each bracket/ wire coupled with a saturated calomel reference electrode was measured via a voltmeter and recorded constantly. Corrosion rate (CR) was calculated, and release of ions was measured with an atomic absorption spectrometer. Stereomicroscope was used to evaluate all samples. Then, samples with corrosion were further assessed by scanning electron microscope and energydispersive X-ray spectroscopy. Two-way analysis of variance was used to analyze data. Results Among ions evaluated, release of nickel ions from Shinye brackets was significantly higher than that of other brackets. The mean potential difference was significantly lower in specimens containing a couple of Shinye brackets and SS wire compared with other specimens. No significant difference was observed in the mean CR of various groups (p>0.05). Microscopic evaluation showed corrosion in two samples only: Shinye bracket coupled with SS wire and American Orthodontics bracket coupled with NiTi wire. Conclusion Shinye brackets coupled with SS wire showed more susceptibility to galvanic corrosion. There were no significant differences among specimens in terms of the CR or released ions except the release of Ni ions, which was higher in Shinye brackets. How to cite this article Tahmasbi S, Sheikh T, Hemmati YB. Ion Release and Galvanic Corrosion of Different Orthodontic Brackets and Wires in Artificial Saliva. J Contemp Dent Pract 2017;18(3):222-227.

45

Lari, Arezou, Nafiseh Esmaeili, and Homanaz Ghafari. "Ionic liquid functionlized on multiwall carbon nanotubes for nickel and lead determination in human serum and urine samples by micro solid-phase extraction." Analytical Methods in Environmental Chemistry Journal 4, no. 02 (June 30, 2021): 72–85. http://dx.doi.org/10.24200/amecj.v4.i02.144.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

In this study, a novel synthesis adsorbent, 1-(3-aminopropyl)-3-methylimidazolium hexafluorophosphate functionlized on multiwall carbon nanotubes ([Apmim][PF6]-MWCNTs, IL@MWCNTS) was used for nickel/lead (Ni/Pb) extraction and determination by dispersive ionic liquid micro solid-phase extraction (DIL-μ-SPE) coupled to electrothermal atomic absorption spectrometry (ET-AAS). After dilution of 20 mg of IL@MWCNTS in 200 μL of acetone, the mixture was injected to 10 mL of human serum/urine samples at pH of 8.0. After sonication for 5 min, the Ni(II) / Pb(II) were extracted by ionic liquid phase and then centrifuged for 2.5 min. The upper liquid phase set aside and Ni(II) / Pb(II) loaded in adsorbent were back-extracted by acidic solution at pH=2-3. Finally, the concentration of total nickel and lead was determined by ET-AAS. By optimizing, the limit of detection, linear range, and enrichment factor for nickel and lead were obtained (0.05 μg L−1; 0.1 μg L−1), (0.2-5.8 μg L−1; 0.4-30 μg L−1) and 24.7; 5.1, respectively (RSD less than 5%). Also, the capacity absorption of IL@MWCNTS for nickel and lead ions were achieved 149.3 mg g-1 and 162.5 mg g-1, respectively. The DIL-μ-SPE procedure was validated for nickel and lead extraction by spiking of real samples and ICP-MS analyzer.

46

Yildiz, Sayiter, and Selahattin Sevinç. "Heavy Metal Adsorption by Dewatered Iron-Containing Waste Sludge." Ecological Chemistry and Engineering S 25, no. 3 (September 1, 2018): 431–56. http://dx.doi.org/10.1515/eces-2018-0030.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract Drinking water treatment plants produce significant amounts of waste sludge. In this study, removal of Nickel ion by use of wastewater sludge was aimed. The adsorption capability of waste sludge was optimized with varying physical parameters such as pH, adsorbent dosage, adsorbate concentration, contact time, shaking speed and temperature. Initial concentration was set as 25 mg/dm3, absorbent dose was set as 0.3 g/cm3, and temperature was set as 25 °C. Compliance of balance data with Langmuir, Freundlich, Temkin and D-R isotherm models was investigated. The highest R2 values were obtained with Freundlich isotherm (R2 = 0.92-0.95). Adsorption kinetics was analysed using pseudo-first order, pseudo-second order, Weber and Morris intraparticle diffusion and Elovich kinetic models, and the system was found to be in a better compliance with pseudo-second order kinetic model. Iron sludge was used as sorbent, and accordingly total iron ion measurements were carried out to determine its possible effects on water. Additionally, SEM, EDX, FTIR spectroscopy, XRD spectrum and atomic force microscope (AFM) measurements were conducted to determine the interaction between the sorbent and metal ions, in addition to characterization of the sorbent. As indicated by research results, drinking water treatment sludge proved to be a potential adsorbent for removal of nickel(II) ions from the solution.

47

Al-Dalain, Sati Y., Moawiya A. Haddad, Salvatore Parisi, Mousa Atallah Al-Tarawneh, and Haitham Qaralleh. "Determination of Macroelements, Transition Elements, and Anionic Contents of Commercial Roasted Ground Coffee Available in Jordanian Markets." Beverages 6, no. 1 (March 9, 2020): 16. http://dx.doi.org/10.3390/beverages6010016.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Coffee is one of the most common drinks worldwide. Due to the variability of elements composition, coffee is important for human health. The aim of this study is to assess the concentration of certain selected elements of commercial samples of roasted ground coffee available in Jordanian markets. The concentrations of macroelement components (sodium, potassium, and calcium), transition elements (lead, cadmium, iron, nickel, and copper), and anion contents (sulfate, nitrate, fluoride, chloride, and phosphate ions) have been determined in nine samples using atomic absorption spectroscopy. Obtained results showed that all tested samples contain macroelementscalcium, sodium, and potassium, in a concentration ranging from 6.18 to 162.6 μg/gram of dry weight (in detail: calcium, 6.96–9.81 μg/g; sodium, 121.54–162.60 μg/g; potassium, 6.18–10.23 μg/g). Regarding transition elements, all samples tested contained variable concentrations of iron and copper (1.26–2.07 and 0.24–0.66 μg/g, respectively), while they lacked lead, cadmium, and nickel (only one sample contained 0.1 μg/g for nickel). In addition, all tested samples contained variable anionic concentrations. The lack of toxic selected elements (lead, cadmium, and nickel) in these samples appears to indicate the significance of these coffee samples as a source of useful selected elements for human health.

48

Filatova, Elena G., and Yury N. Pozhidaev. "Kinetics and Adsorption Ions of Heavy Metal by Modified Alumino-Silicates." Solid State Phenomena 316 (April 2021): 170–74. http://dx.doi.org/10.4028/www.scientific.net/ssp.316.170.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Adsorption isotherms of Ni (II) and Cu (II) ions by alumino-silicates, modified with N, N'-bis (3-triethoxysilylpropyl) thiocarbamide (BTM-3), and HCl, were obtained. The adsorption kinetics of heavy metal ions is studied, using the kinetic pseudo-first and pseudo-second order models. It is shown that, when alumino-silicates are modified, the rate and energy of adsorption increase. It is established that the kinetics of the adsorption of the studied ions is best described by a pseudo-second order model. The maximum value of the adsorption rate constant of 33.7∙10-5 g/ (mmol min) corresponds to nickel (II) ions for alumino-silicates, modified with HCl. The maximum value of the adsorption rate constant value of 2.91∙10-5 g/ (mmol min) for alumino-silicates, modified with BTM-3, corresponds to Cu (II) ions.

49

Elliott, S., P. Beiersdorfer, and J. Nilsen. "Measurements of 3d-5fand 3d-6ftransition energies in nickel-like ions for resonant photopumping by helium-like ions." Physica Scripta 49, no. 5 (May 1, 1994): 556–60. http://dx.doi.org/10.1088/0031-8949/49/5/009.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Ipeaiyeda, Ayodele Rotimi, and Adekunle Johnson Odola. "Co-precipitation of Ni, Cr, Mn, Pb and Zn in industrial wastewater and sediment samples with copper(II) cyclo-hexylmethyldithiocarbamate for their flame atomic absorption spectrometric determination." Water Science and Technology 66, no. 1 (July 1, 2012): 105–12. http://dx.doi.org/10.2166/wst.2012.119.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

A co-precipitation technique for nickel(II), chromium(II), manganese(II), lead(II) and zinc(II) with the aid of copper(II) cyclo-hexylmethyldithiocarbamate was established. The influences of some analytical parameters such as pH, sample volume, amounts of cyclo-hexylmethyldithiocarbamate and copper(II) on the recovery of metal ions were investigated. The heavy metals in the precipitate were determined by flame atomic absorption spectrophotometry. The range of detection limits for the heavy metals was 0.003–0.005 mg/L. The atomic spectrometric technique with co-precipitation procedure was successfully applied for the determination of Ni, Cr, Mn, Pb and Zn in industrial wastewater and sediment samples from Ladipo stream in Lagos, Nigeria. The mean concentrations for these metals using co-precipitation procedure were not significantly different from corresponding concentrations obtained using spectrometric techniques without co-precipitation procedure.

Статті в журналах з теми "Nickel atomic ions"

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями