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1

Chalcopyrite leaching by amino acid solutions in the presence of hydrogen peroxide

Nurtazina Nargiza, Uvarov Nikolai, Azhigulova Ryskul, Tyapkin Pavel

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 6

art. no. 157067

EN

It is demonstrated that amino acids such as glycine, betaine, and lysine may be applied as selective copper leaching agents in the process of hydrochemical oxidation of chalcopyrite at atmospheric pressure and in the temperature range 25÷65 °C. The advantage of the proposed method is its relative environmental friendliness. Solid samples of the initial mineral and leached chalcopyrite residues were analyzed by X-ray diffraction analysis, and Mössbauer and Raman spectroscopy. The results of the atomic absorption analysis showed that copper's extraction efficiency increased when the experiment's duration was raised and when the process temperature was higher. The leaching ability of amino acids was evaluated by the specific leaching rate of chalcopyrite in these reagents. Amino acid leaching was thought to be mainly due to the complexation of copper (II) glycinates, copper (II) betainates and copper (II) lysinates. This reaction can be enhanced by adding hydrogen peroxide to the system as an oxidant. It was determined that glycine was more effective as a leaching agent than betaine and lysine. Based on experimental data, it was assumed that the most possible mechanism is selective copper leaching due to the formation of chalcopyrite-based solid solution Cu1-XFeS2.

2

Experimental and computational investigation with Hirshfeld surface analysis of bis(glycine) strontium dichloride trihydrate

Radhakrishnan Anbarasan, Muppudathi Anna Lakshmi, Jeyaperumal Kalyana Sundar

Materials Science Poland

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2020

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Vol. 38, No. 4

545--552

EN

Good-quality semiorganic single crystals of bis(glycine) strontium dichloride trihydrate (GSC) were grown by slow evaporation technique. The lattice parameters of the grown crystal were verified through single crystal X-ray diffraction. Besides, the crystallinity of the material was analyzed with powder X-ray diffraction. The fingerprint of functional groups of this material was analyzed by FT-IR technique. The UV transparency cutoff wavelength of GSC was found to be 240 nm and the crystal exhibited 80 % transmission in the entire visible region. All intermolecular and intramolecular interactions of the grown crystal were interpreted by Hirshfeld surface analysis, and the strength of the interactions was graphically illustrated by fingerprint graphs. The intramolecular charge transfers of the crystal were assessed through frontier molecular orbital analysis.

3

Effect of fuel type on the combustion reaction behavior, phase structure and morphology of Ni0.5Co0.5Fe2O4 nanoparticles

Sedghi Arman, Salehkooh Elham Akbari, Chadorbafzade Monireh

Materials Science Poland

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2020

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Vol. 38, No. 2

341--349

EN

Nickel-cobalt ferrite spinels are ferrimagnetic ceramic materials that possess a great potential for application in high-density magnetic media, recording, color imaging, ferrofluids, and high-frequency devices. A change of their structure from micro- to nano- improves their properties drastically, therefore many methods have been investigated to fabricate nanopowder of these spinels. Gel combustion method is one of them. In this research, Ni0.5Co0.5Fe2O4nanoparticles were fabricated via gel combustion method using metallic nitrates as an oxidant and citric acid, glycine and urea as fuels and the effects of fuel type on the reaction behavior, structure and morphology of Ni0.5Co0.5Fe2O4nanoparticles were investigated. The reaction behavior was studied by thermal analysis method (TGA-DTA), crystallite size of powders was characterized by X-ray diffraction (XRD) and their morphology was studied by FE-SEM. The results revealed that the reaction was initiated in urea, glycine and citric at 219 °C, 197 °C, 212 °C, respectively. Samples fabricated from glycine and citric acid had a pure spinel structure but the others fabricated with urea fuel had iron oxide impurity. The crystallite size of nickel cobalt ferrite nanoparticles was in the range of 58 nm to 64 nm and the nanoparticles were agglomerated.

4

Dielectric, etching and Z-scan studies of glycine doped potassium thiourea chloride crystal

Azhar S. M., Anis M., Hussaini S. S., Kalainathan S., Shirsat M. D., Rabbani G.

Materials Science Poland

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2016

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Vol. 34, No. 4

800--805

EN

Glycine doped potassium thiourea chloride (PTC) crystal has been grown by slow solution evaporation technique. The dielectric studies have been employed to examine substantial improvement in dielectric constant and dielectric loss of glycine doped PTC crystal. The etching studies have been performed to investigate the surface quality of this crystal. The z-scan studies have been carried out at 632.8 nm to explore the third order nonlinear optical nature. The negative nonlinear refraction of glycine doped PTC crystal was found to be of 7.27 × 10-12cm2/W. The origin of high magnitude of third order nonlinear optical susceptibility and reverse saturable nonlinear absorption have been investigated. The obtained results were explored to discuss the nonlinear optical applications of PTC crystal.

5

Wpływ osnowy polimerowej na piezooptykę nanokrystalitów γ-glicyny

Oźga K., Nabiałek M., Szota M., Rakus P., Czaja P., Dośpiał M., Berdowski J., Tylczynski Z.

Przetwórstwo Tworzyw

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2011

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[R.] 17, nr 6

483-487

PL

Ustalono główną rolę polarności osnów polimerowych na dyspersję zjawiska piezooptyki nanokrystalitów γ-glicyny wprowadzonych w osnowy polimerowe poli(metakrylanu metylu) (PMMA) oraz poliwęglanu (PC). Stwierdzono pojawienie się efektu piezooptycznego pod wpływem obróbki laserowej dwoma wiązkami świetlnymi o długości fali 1064 nm oraz 532 nm, generowanymi z jednego źródła laserowego YAG: Nd. Optymalne rozmiary nanokrystalitów γ-glicyny, dla których otrzymano odpowiednie wartości współczynników piezooptyczych wynosiły 50-80 nm (optymalna koncentracja 5,5 % w j. wag.). W pracy badano relaksacje oraz zależności spektralne odpowiednich współczynników tensora piezooptycznego.

EN

We have established a principal role of the polarity of polymer matrices on the piezooptical dispersion of the γ-glycine nanocrystallites embedded into the polymethymethacrylate (PMMA) and polycarbonate (PC) matrices. We have found that the optical treatment by bicolor two laser beams at 1064 nm and 532 nm which are originating from the same 10 ns Nd:YAG lasers, causing occurrence of the piezooptical effects. The optimal content of the γ-glycine nanocrystallites with respect to the magnitude of piezooptical coefficients with the sizes within the range 50-80 nm correspondence to the 5.5 % in weighting unit. We studied relaxation and spectral dependences of the corresponding coefficients of piezooptic tensor.

6

Synthesis and Characterization of Two Novel Inorganic-Organic Hybrid Materials Based on Polyoxotungstoborate: [L-C2H5NO2-H]3[H2BW12O40]ź5H2O and [CH4N2O-H]2[H3BW12O40]ź5H2O (C2H5NO2 = Glycine; CH4N2O = Urea)

Alizadeh M. H., Eshtiagh-Hosseini H., Mirzaei M., Hosseini-Nejad M.

Polish Journal of Chemistry

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2009

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Vol. 83, nr 9

1583-1589

EN

Two novel hy drated in or ganic-or ganic hy brids, namely [L-C2H5NO2-H]3[H2BW12O40]ź ź5H2O (1) and [CH4N2O-H]2[H3BW12O40]ź5H2O (2), where C2H5NO2 and CH4N2O are glycine and urea, respectively, have been synthesized and characterized by CHN microanalysis, IR, UV, and 1H NMR spectroscopies. According to the obtained results, molecular structure of 1 consists of tungstoborate anions linked to glycinium cations via van der Waals interactions and hydrogen bonding. Three [L-C2H5NO2-H]+ moieties encompass each [H2BW12O40]3- and, almost certainly, the same is true for 2. The O atoms of polyoxometalates and water, as well as the N atoms of L-glycine and urea are in volved in hydrogen bonding. Characteristic UV bands of the Keggin anion, alfa-H5[BW12O40]ź ź19H2O, are observed at 257 nm, as would be expected.

7

Stability of Mn(II) Complexes with Acetic Acid Derivatives

Pedras M., John E.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 10

1701-1706

EN

Composition and stability constants of Mn(II) complexes with acetic, glycolic (hydroxyacetic), methoxyacetic and phenylacetic acids, glycine (aminoacetic acid), and sarcosine (N-methylglycine) were determined, at a constant ionic strength = 0.1 KNO3 using the potentiometric method at 20 graduate C. Values of stability constants were found by Bjerrum graphical method and also numerically using Martell and Motekaitis program. The following logK1,graph. values of Mn(II) complexes were found: 2.21 for the complex with acetic acid, 2.45with glycolic acid, 2.10 with methoxyacetic acid, 2.48 with phenylacetic acid, 3.10 with glycine and 3.05 with sarcosine.