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Russian Journal of Physical Chemistry A, Focus on Chemistry
Journal Prestige (SJR): 0.255

Citation Impact (citeScore): 1
Number of Followers: 0

Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0036-0244 - ISSN (Online) 1531-863X
Published by Springer-Verlag

[2469 journals]

Thermodynamics of the Complexation of Nd3+, Eu3+, Gd3+, and Yb3+ Ions with
Glycyl-Glycyl-Glycine in Aqueous Solutions in the pH Range 1.8–7.6
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  Abstract: Enthalpies of triglycine complexation are determined calorimetrically (HL±) with ions of neodymium(III), europium(III), gadolinium(III), and ytterbium(III) at a temperature of 298.15 K and an ionic strength of 0.1, using KNO3 as the background electrolyte. The thermodynamic characteristics of the formation of complexes of the tripeptide and ions are calculated. Nd3+, Eu3+, Gd3+, and Yb3+composition LnL2+ at different [metal] : [ligand] molar ratios in the 1.8–7.6 range of pH. Analysis of the resulting enthalpies of complexation confirms the preferred coordination of the central lanthanide ion through the carboxylic oxygen atom of triglycine, known from the literature.
  PubDate: 2022-04-01
Effect of Graphene Flakes on the Physical and Chemical Properties of
Magnetite Magnetic Fluids
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  Abstract: Results are presented from a physicochemical study of magnetite magnetic fluid of synthesized with addition of graphene. It is shown that adding graphene during the synthesis of the dispersed phase affects the specific surface of the magnetic phase, the thermal stability, the viscosity, and the heat capacity of the magnetic fluid.
  PubDate: 2022-04-01
Atomistic Computer Modeling of Hydrocalumite As an Adsorbent for
Radioactive Anions from Aqueous Solutions
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  Abstract: Results are presented from atomistic computer modeling of hydrocalumite (cement AFm-phase) with Cl− and I− anions in the interlayer space as a potential adsorbent of radionuclides 36Cl, 129I, 137Cs. Properties of the crystals themselves and the interaction between aqueous solutions of CsCl and CsI and surfaces of crystalline phases are studied. It is shown the adsorption of Cl− is stronger than that of I− on surfaces of hydrocalumite, which can be explained by the difference in ionic radii of hydrated anions.
  PubDate: 2022-04-01
Solvation of Cobalt Tetrasulfophthalocyanine in Water–Acetonitrile
Solvents
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  Abstract: The method of distribution between two immiscible phases is used to determine Gibbs free energies of transfer of cobalt tetrasulfophthalocyanine from water to water-acetonitrile mixtures ( \({{\Delta }_{{{\text{tr}}}}}{{G}^{0}}{{({\text{CoTSPc}})}_{{{\text{aq}} \to \chi {\text{AN}}}}}\) ; χAN = 0.0–0.5 mole fractions) at 25°C. The effect of the mixed solvent composition and properties on change in the solvation state of CoTSPc was analyzed. It is found that increasing the content of the organic component in the mixed solvent results in desolvation of the phthalocyanine metal complex. Changes in the solvation state of CoTSPc are associated with a weakening of the solvation of the aromatic system due to a reduction in the energy of the universal solute–solvent type of interaction. Contributions from the resolvation of electron-donor and electron-acceptor centers of the macroheterocycle to \({{\Delta }_{{{\text{tr}}}}}{{G}^{0}}{{({\text{CoTSPc}})}_{{{\text{aq}} \to \chi {\text{AN}}}}}\) practically compensate each other.
  PubDate: 2022-04-01
Protolytic Equilibrium Constants in Aqueous Solutions of
Pyridoxal-5'-Phosphate Hydrazone and L-Tyrosine
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  Abstract: Protolytic equilibrium constants in an aqueous solution of pyridoxal-5'-phosphate hydrazone and L-tyrosine are determined spectrophotometrically at 25.0 ± 0.1°C and near-zero ionic strength. The obtained constants agree with the literature data for similar compounds.
  PubDate: 2022-04-01
Hybrid Structure Based on Polymer/Silicon Nanowires for Electrochemical
Sensing of para-Nitrophenol
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  Abstract: This work describes the development of hybrid devices based on silicon nanowires (SiNW) and polythiophene (PTh) and its application in electrochemical sensing of para-nitrophenol (p-NPh). p-NPh poses a threat to humanity due to their carcinogenic and recalcitrant properties. It is not easily degradable, so it can affect soils especially groundwater for long time. SiNW were prepared using metal assisted chemical etching by immersing silicon substrates into aqueous hydrofluoric acid solution containing silver nitrate. PTh was covalently grafted on SiNW surface by electrochemical polymerization of thiophene monomer in acetonitrile solvent. The morphology of the fabricated SiNW/PTh hybrid structure was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and contact angle measurements. Cyclic voltammetry was used to study the proposed p-NPh electrochemical sensor. The linearity of the sensor for the detection of p-NPh was observed from 1.5 × 10−8 to 1.5 × 10−4 M.
  PubDate: 2022-04-01
The Effect of Complex Periodic Ellipsoid Arrays on Light Extraction
Efficiency of GaN Based LED
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  Abstract: A novel ellipsoidal complex period photonic crystal array etching on gallium nitride (GaN) was presented in order to improve the light extraction efficiency of GaN based light emitting diode (LED). The effect of various structural parameters of ellipsoid complex photonic crystals on the light extraction efficiency of LED were assessed by finite difference time domain method (FDTD) to obtain the optimum light extraction efficiency by the parameters optimization. The results show that when the width of the large ellipsoid D1 = 0.72 μm, the height T1 = 1.008 μm, the width of the small ellipsoid D2 = 0.16 μm, the height T2 = 0.336 μm, and the lattice constant period a = 0.8 μm, the light extraction efficiency of LED can reach up to 18.98%. It is helpful for understanding the light extraction efficiency mechanism of GaN based LED, which also implies a potential method for the parameters design of GaN based LED.
  PubDate: 2022-04-01
Size Effect in the Phase Separation in Three-Component Solutions
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  Abstract: A thermodynamic model of the three-component solution with phase separation is proposed. Results from modeling are presented for several ternary systems with core-shell structure. The model is based on a numerical analysis of the Gibbs function that considers the surface energy of the external and internal interphase boundaries. Ternary mixtures with phase separation corresponding to the equations of state of regular, Flory–Huggins, and NRTL solutions are considered as examples. Modeling describes thermodynamically stable and metastable states that are missing from macrosystems. It is shown that the volume and composition of a heterogeneous mixture affects the region of heterogeneity, the equilibrium composition of coexisting phases, and the number of metastable states. A region of the bi-stability of phase equilibria is revealed in which there is competition between different core–shell structures.
  PubDate: 2022-04-01
Structure and Mechanisms of Trichostatin A Drug Adsorption on Graphene
Oxide: Density Functional Theory Approach
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  Abstract: Due to the unique physiological properties of the graphene-oxide (GO) such as excellent solubility, high area and low toxicity have been widely studied in many fields. In this study, adsorption mechanisms of the Trichostatin A (TSA) drug on the GO have been investigated. Electronic energies and structural properties are investigated intimately in an aqueous solution at M06-2X/6-31G(d,p) level of theory. Five different configurations of adsorption of the TSA on the GO have been studied. It has been concluded that the epoxy and hydroxyl groups are the two dominant groups that play a crucial role in adsorption of the TSA drug. The best interaction mode between the TSA and the GO was determined.
  PubDate: 2022-04-01
Effect of Cu2+ Doping on the Photocatalytic Properties of Calcium Titanate
and the Intermediate Products of Its Synthesis
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  Abstract: A comparative analysis is performed to determine the effect Cu2+ doping has on chemical and phase compositions, along with the effect the conditions of the formation of features of complex oxide powders have on their photocatalytic activity.
  PubDate: 2022-04-01
Study on Thermodynamic and Transport Properties of Binary Liquid Mixtures
(N-Methylformamide with Aniline, N-Methylaniline, and N,N-Dimethylaniline)
at Various Temperatures
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  Abstract: Densities (ρ), speeds of sound (u), and viscosities (η) of binary mixtures of N-methylformamide (N-MF) with aniline (A), N-methylaniline (N-MA), and N,N-dimethylaniline (N,N-DMA) including those of pure liquids, over the entire composition range were measured at temperatures (303.15, 308.15, and 313.15 K) and 0.1 MPa. Using the experimental data, the excess volume (VE), excess isentropic compressibility ( \(\kappa _{s}^{E}\) ), deviation in viscosity (∆η), excess partial molar volumes, \(\bar {V}{}_{{{\text{m}}{\text{,1}}}}^{E}\) and \(\bar {V}{}_{{{\text{m}}{\text{,2}}}}^{E}\) , and excess partial molar isentropic compressibilities, \(\bar {K}{}_{{{\text{s}}{\text{,m}}{\text{,1}}}}^{E}\) and \(\bar {K}{}_{{{\text{s}}{\text{,m}}{\text{,2}}}}^{E}\) of the components at infinite dilution were calculated. The VE results have been analyzed in the terms of Prigogine–Flory–Patterson theory. An analysis of each of the three contributions viz. interactional, free volume and P* to VE shows that free volume effects are negative for all the binary mixtures. FT-IR (Fourier transform infrared spectroscopy) properties have been carried out to study the specific interaction such as formation of hydrogen bond between unlike molecules in the binary liquid mixtures; a good agreement is observed among the excess parameters and FT-IR spectroscopic properties.
  PubDate: 2022-04-01
Photoinduced Absorption Spectra of Donor–Acceptor Systems Based on
Cobalt(II) and Manganese(III) Phthalocyanine Complexes with Femtosecond
Time Resolution
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  Abstract: Results of studying the ultrafast dynamics of excited states of cobalt(II) and manganese(III) octakis(3,5-di-tert-butylphenoxy)phthalocyanines, along with donor–acceptor systems based on them with fullero[60]- and fullero[70]pyrrolidines as acceptors are represented. Excited states are achieved by exposing the absorbing substances to laser pulses in femtosecond absorption spectroscopy. The kinetics and types of photoinduced absorption spectra of metal phthalocyanines and their dyads with substituted pyrrolidines are described, along with the lifetimes of states with separated charges. The corresponding constants of charge separation and recombination are determined.
  PubDate: 2022-04-01
Role of Silver Catalyst in Synthesis of Porous Silicon and Vertically
Aligned Nanostructures with High Aspect Ratio without Using Lithography
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  Abstract: Metals like silver, gold, and nickel etc. are prominently used as catalyst for synthesis of nanostructures. Synthesis of silicon nanostructures by top-down mechanism is basically a subtractive technique which proceeds by a sequential oxidation followed by dissolution. The basic mechanism involves transport of the reactant to the surface, reaction at the surface, and movement of reaction products into the volume of the etchant solution. Porous Si and nanostructures with high aspect ratio in the form of nanowires on p-type silicon (100) substrate have been synthesized by low cost, well controlled method in the material research laboratory using isotropic wet etching process without the use of any lithography or mask. The morphological characterization has been done by field emission scanning electron microscope (FESEM). It has been observed that the same method is applicable to develop porous surface and to synthesize well-aligned nanowire arrays perpendicular to the surface of the silicon substrate. The measured average length of a nanowire in the array is around 8 µm. The effect of etching time on the growth of nanowires has been studied and it is observed that the length of nanowire increases as we increase the etching time. Detailed analysis of the physical and chemical processes has been done and improved course of action is suggested. Silicon nanowires, among varieties of potential applications, have exhibited promising use in electronic industries ranging from electronic components to photovoltaic. Its high aspect ratio and low reflectance make silicon nanowire (SiNW) array suitable candidate for opto-electronic industries particularly for manufacture of high efficiency solar cells.
  PubDate: 2022-04-01
Investigation on Formaldehyde SAW Sensor with ZnO Film Prepared through
Radio Frequency Magnetron Sputtering
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  Abstract: The ZnO films were deposited on the surface acoustic wave (SAW) chip by radio frequency magnetron sputtering. Sputtering power of 50, 100, and 150 W were selected and three kinds of ZnO-SAW sensors were successfully prepared. The adsorptive properties of HCOH on ZnO-SAW sensors were investigated. For different concentrations of HCOH, the frequency response of the ZnO-SAW sensor prepared at 100 W sputtering power was obviously higher than that of the ZnO-SAW sensors prepared at the other sputtering power values. The sensitivity of this sensor to 1–50 ppm HCOH was 114.99 Hz/ppm, and the lowest concentration detected was about 0.1 ppm. Moreover, the density functional theory (DFT) calculations were performed to elucidate the structural, electronic and adsorptive properties of the fabricated sensors. The calculated results showed that adsorption of HCOH on ZnO has physical nature.
  PubDate: 2022-04-01
Magnetocaloric Effect in α'-MnB Nanoparticles
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  Abstract: In this work, the dependence of magnetization temperature for α'-MnB nanoparticles has been simulated to predict magnetocaloric effect (MCE) parameters of α'-MnB nanoparticles. The results reveal that MCE of α'-MnB nanoparticles covers a large range of temperature between 300 and 550 K. We suppose that α'-MnB nanoparticles can be used as a single function magnetic material for magnetic refrigerator (MR) which can be used in the automotive, food, or aerospace industries.
  PubDate: 2022-04-01
Synthesis of C–N@GC Nanomaterial Derived from Core-Shell ZIF-8@ZIF-67
and Its Application in the Detection of L-Cysteine
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  Abstract: Nanomaterial derived from core-shell ZIF-8@ZIF-67, i.e., C–N@GC has been successfully fabricated and characterized by TEM and SEM. C–N@GC was then supported on the glassy carbon electrode and applied to detect L-cysteine. The electrochemical detection results showed that the electrocatalytic current increased linearly with the L-cysteine concentration in the range of 0.2–8 mM with the detection limit of 50 µM. In addition, the presented electrochemical sensor has good selectivity for the determination of L‑cysteine in the presence of other interfering species. Therefore, C–N@GC modified GCE is a promising L‑cysteine sensor, due to good conductivity and synergetic effect between C–N and GC in C–N@GC.
  PubDate: 2022-04-01
Electronic and Magnetic Properties of Iron Doped Graphene Nanoribbons
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  Abstract: Using density functional theory, the structural stabilities, electronic and magnetic properties of Fen (n = 3–6) clusters absorbed on defect armchair graphene nanoribbons are systematically investigated. We found that such systems have high stabilities and large magnetic moments. From n = 3, the binding energies are very important. This can be explained by the fact that a triangularization phenomenon between iron atoms and also more bonds with neighboring carbon atoms. Fe3-3V-AGNR exhibits a half-metal behavior with 61% spin polarization. Other doped structures (n = 4–6) exhibit semiconductor behavior.
  PubDate: 2022-04-01
MOF-Derived Co3O4/C Microspheres As High-Performance Anode Materials for
Lithium-Ion Batteries
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  Abstract: Co3O4/C composites with microsphere structure were prepared by heat treatment of Co-based metal-organic framework (MOF). The structure and composition of Co3O4/C material were studied by X‑ray diffraction (XRD), scanning electron microscopy (SEM), and other test methods. In the voltage range of 0.01–3.0 V and the current density of 0.05 A g–1, the initial capacity of Co3O4/C calcined at 600°C is 1554.25 mA h g–1. After 60 times of charging and discharging at different current densities, Co3O4/C-600 has excellent rate performance and maintains a specific capacity of 1042 mA h g–1 at a current density of 0.05 A g–1. The good rate performance of Co3O4/C-600 is due to the structure which is dispersed on the carbon substrate and the excellent specific surface area. Therefore, Co3O4/C composite is considered as promising anode material for lithium batteries.
  PubDate: 2022-04-01
Intermolecular Interactions between Chlorpheniramine with 1-Butanol,
1-Pentanol, and 1-Hexanol
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  Abstract: Density (ρ), viscosity (η), and ultrasonic velocity (U) are studied for binary liquid mixtures of chlorpheniramine with 1-butanol, 1-pentanol, and 1-hexanol at 303 K. Adiabatic compressibility (β), free length (Lf), free volume (Vf), internal pressure (πi), viscous relaxation time (τ), and Gibbs free energy (ΔG) are calculated by using the experimental data. The excess values of the above parameters (βE, \(L_{{\text{f}}}^{{\text{E}}}\) , \(V_{{\text{F}}}^{{\text{E}}}\) , \(\pi _{{\text{i}}}^{{\text{E}}}\) , τE, and ΔGE) from their ideal values are also determined and fitted with Redlich–Kister polynomial equation. The changes in the determined parameters are interpreted in terms of the intermolecular interaction between the liquid mixtures. The significant changes in the ideal parameters and the excess parameters have confirmed the existence of the intermolecular interactions between the selected liquid system. From the observations, strength of intermolecular interaction of chlorpheniramine with the selected alcohols is in the order of 1‑butanol < 1-pentanol < 1-hexanol.
  PubDate: 2022-04-01
Study on the Physical Properties and Electric Dissociation of Hydrogen
Sulfide under the Action of Strong Field
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  Abstract: Hydrogen sulfide (H2S) is a widespread atmospheric pollutant. Based on the density functional theory (DFT) at the BPV86/6-31++G(d,p) level, the physical and chemical properties of H2S under the external electric field are investigated, including the geometry, frontier orbital energy, infrared (IR) absorption spectrum and Ultraviolet-visible (UV–Vis) absorption spectrum. Besides, the potential energy curves obtained at the BPV86/6-31G(d,p) level mean the dissociation of H2S may realize under the electric field of 61.704 V nm–1. The results indicate that applying a strong electric field on H2S may be a method to solve the pollution of H2S and other sulfur compounds.
  PubDate: 2022-04-01