Kinetic studies of gold(III) chloride complex reduction and solid phase precipitation in acidic aqueous system using dimethylamine borane as reducing agent

Micellar electrokinetic chromatography (MEKC) was investigated for the simultaneous determination of letrozole, imipramine and their metabolites in human urine samples over a concentration range of therapeutic interest. Experimental parameters such as pH of the running electrolyte, sodium dodecylsulphate (SDS) concentration, borate concentration, voltage, etc were investigated. Under optimal conditions of 25 mM SDS, 15 mM borate buffer (pH 9.2), 15% 2-propanol, as background electrolyte; 28 kV and 40 °C, as voltage and cartridge temperature, respectively; resolution between the peaks was greater than 1.7. Before the determination, a solid phase extraction (SPE) procedure with a C18 cartridge was optimized. Good linearity, accuracy, precision, robustness and ruggedness were achieved and detection limits of 12.5 ng/mL for letrozole and its metabolite and 37.5 ng/mL, were obtained for imipramine and their metabolites. Real determinations of these analytes in two patient urines were carried out. Sensitivity achieved in this method is sufficient to perform kinetic studies in humans.

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Solubility and Solubility-Limiting Solid Phase in M(IV)-OH-Dicarboxylate Ternary Aqueous System

Journal of Nuclear Science and Technology ◽

10.1080/18811248.2011.9711786 ◽

2011 ◽

Vol 48 (7) ◽

pp. 993-1003 ◽

Cited By ~ 4

Author(s):

Taishi KOBAYASHI ◽

Takayuki SASAKI ◽

Ikuji TAKAGI ◽

Hirotake MORIYAMA

Keyword(s):

Solid Phase ◽

Aqueous System

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Kinetic Studies on the Direct Solid Phase Radioimmunoassay for Hepatitis B Antigen

Vox Sanguinis ◽

10.1159/000467753 ◽

1974 ◽

Vol 26 (3) ◽

pp. 209-221

Author(s):

Alfred M. Prince ◽

Dan Jass

Keyword(s):

Hepatitis B ◽

Solid Phase ◽

Kinetic Studies ◽

Hepatitis B Antigen ◽

Solid Phase Radioimmunoassay ◽

Direct Solid

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Iron reduction from concentrates of hydrometallurgical dressing

Izvestiya Ferrous Metallurgy ◽

10.17073/0368-0797-2021-10-728-735 ◽

2021 ◽

Vol 64 (10) ◽

pp. 728-735

Author(s):

I. A. Rybenko ◽

O. I. Nokhrina ◽

I. D. Rozhikhina ◽

M. A. Golodova ◽

I. E. Khodosov

Keyword(s):

Experimental Study ◽

Thermal Decomposition ◽

Thermodynamic Modeling ◽

Iron Reduction ◽

Solid Phase ◽

Experimental Studies ◽

Statistical Processing ◽

Reducing Agent ◽

Volatile Components ◽

Software Complex

The article presents results of theoretical and experimental studies of the processes of iron solid-phase reduction from an iron-containing concentrate obtained as a result of hydrometallurgical dressing of ferromanganese and polymetallic manganese-containing ores with coals of grades D (long-flame) and 2B (brown). The method of thermodynamic modeling using TERRA software complex was used to study the reducing properties of hydrocarbons by calculating equilibrium compositions in the temperature range of 373 - 1873 K. The authors obtained the dependences of compositions and volume of the gas phase formed as a result of the release of volatile components during heating on the temperature for the coals of the grades under consideration. As a result of thermodynamic modeling, the optimal temperatures and consumption are determined, which ensure the complete iron reduction from an iron-containing concentrate. The results of experimental studies were obtained by modern research methods using laboratory and analytical equipment, as well as methods of statistical processing. Results of the coals analysis carried out using the Setaram LabSys Evo thermal analyzer showed that the process of thermal decomposition of coals of the studied grades proceeds according to general laws. The process of thermal decomposition of long-flame coal proceeds less intensively than of brown coal. The results of an experimental study of the processes of thermal decomposition of reducing agents have shown that volumes of the gas phases, formed when coals are heated to a temperature of 1173 K in an argon atmosphere, practically coincide with the calculated values. As a result of thermodynamic modeling and experimental study, the optimal consumption of D and 2B grades of coal is determined at a temperature of 1473 K. The best reducing agent with a minimum specific consumption is long-flame coal of D grade. When determining the optimal amount of reducing agent in charge mixtures during the study of metallization processes, it was found that with an excess of reducing agent, it is possible to achieve almost complete extraction (98 - 99 %) of iron from the concentrate.

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Solid-phase reactions in shock waves: Kinetic studies and mechanism

Combustion Explosion and Shock Waves ◽

10.1007/bf01992198 ◽

1996 ◽

Vol 32 (1) ◽

pp. 102-113 ◽

Cited By ~ 9

Author(s):

S. S. Batsanov

Keyword(s):

Shock Waves ◽

Solid Phase ◽

Kinetic Studies ◽

Solid Phase Reactions

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Magnetic γFe2O3@Sh@Cu2O: an efficient solid-phase catalyst for reducing agent and base-free click synthesis of 1,4-disubstituted-1,2,3-triazoles

BMC Chemistry ◽

10.1186/s13065-019-0657-9 ◽

2020 ◽

Vol 14 (1) ◽

Cited By ~ 4

Author(s):

Fereshteh Norouzi ◽

Shahrzad Javanshir

Keyword(s):

Photoelectron Spectroscopy ◽

Inductively Coupled Plasma ◽

Solid Phase ◽

Click Reaction ◽

Copper Acetate ◽

Reducing Agent ◽

Gravimetric Analysis ◽

High Turnover ◽

One Pot ◽

X Ray

AbstractA hybrid magnetic material γFe2O3@Sh@cu2O was easily prepared from Shilajit (Sh) decorated Fe3O4 and copper acetate. The prepared magnetic hybrid material was fully characterized using different analysis, including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), inductively coupled plasma (ICP), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM) thermal gravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET). All these analysis revealed that during coating of Fe3O4@Sh using copper salt (II), synchronized redox sorption of CuII to CuI occurs at the same time as the oxidation of Fe3O4 to γFe2O3. This magnetic catalyst exhibited excellent catalytic activity for regioselective synthesis of 1,4-disubstituted-1,2,3-triazoles via one pot three-component click reaction of sodium azide, terminal alkynes and benzyl halides in the absence of any reducing agent. High yields, short reaction time, high turnover number and frequency (TON = 3.5 * 105 and TOF = 1.0 * 106 h−1 respectively), easy separation, and efficient recycling of the catalyst are the strengths of the present method.

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Solid phase precipitates in (Zr,Th)-OH-(oxalate, malonate) ternary aqueous system

Radiochimica Acta ◽

10.1524/ract.2009.1603 ◽

2009 ◽

Vol 97 (4-5) ◽

Cited By ~ 6

Author(s):

Taishi Kobayashi ◽

Takayuki Sasaki ◽

I. Takagi ◽

Hirotake Moriyama

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Solid Phase ◽

Aqueous System ◽

Carboxylate Ligand ◽

X Ray Diffraction ◽

Large Excess ◽

X Ray ◽

Acidic Conditions ◽

Solid Phases

AbstractThe solubility-limiting solid phases in the ternary aqueous systems of Zr(IV)/OH/oxalate, Zr(IV)/OH/malonate, Th(IV)/OH/oxalate and Th(IV)/OH/malonate were characterized by elemental analysis, X-ray diffraction, thermogravimetric analysis and differential thermal analysis. The ternary solid phase of M(IV)/OH/carboxylate was observed to form, even under acidic conditions, depending on the pH and the concentration of carboxylate ligand. In the presence of a large excess of carboxylic acid, however; the binary M(IV)-carboxylate solid phase formed.

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Kinetics and Mechanism of the Redox Reaction Between Pt(IV) Chloride Complex Ions and Sodium Thiosulfate in Aqueous Solution. Part I: Acidic Solution/ Kinetyka I Mechanizm Reakcji Redox Pomiędzy Chlorkowymi Jonami Kompleksowymi Pt(Iv) I Tiosiarczanem Sodu W Roztworach Wodnych. Część I: Roztwór Kwaśny

Archives of Metallurgy and Materials ◽

10.2478/amm-2014-0241 ◽

2014 ◽

Vol 59 (4) ◽

pp. 1413-1420 ◽

Cited By ~ 1

Author(s):

K. Pacławski ◽

J. Piwowonska

Keyword(s):

Acidic Solution ◽

Solid Phase ◽

Sodium Thiosulfate ◽

Chloride Complex ◽

Elementary Step ◽

Kinetics And Mechanism ◽

Complex Ions ◽

Mechanism Of Reaction ◽

Entropy Of Activation ◽

Enthalpy And Entropy

Abstract In this work, spectrophotometric studies of the kinetics and mechanism of reaction between [PtCl6]2- complex ions and sodium thiosulfate, were carried out. The influence of different conditions, such as: initial concentrations of reductant and platinum(IV) complex ions, ionic strength, pH and temperature on the rate constant, was experimentally determined. From the obtained results, the molecularity of the first elementary step, value of the enthalpy and entropy of activation in Eyring equation as well as corresponding rate equation, were experimentally determined. It was found that the reaction is relatively slow and leads to the S, Pt and PtS colloids formation. The best conditions for solid phase formation containing Pt are at pH = 5.

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