On the structural and magnetic properties of amorphous Fe84−x W x B16 alloys in dependence of W content

A series of rapidly solidificated amorphous Fe_84?x W _x B₁₆ (x=0–5) alloys have been studied. A strictly linear decrease ofH _eff versus concentration of W has been observed by Mössbauer spectroscopy.     

Determination of mitomycin C in urinary bladder tissue by reversed-phase high-performance liquid chromatography

A procedure was developed for the determination of an anticancer drug of mitomycin C (MMC) in urinary bladder tissue samples by reversed-phase high-performance liquid chromatography with spectrophotometric (365 nm) and mass-spectrometric detection with detection limits of 50 and 10 ng/mL, respectively (signal-to-noise ratio = 3). The tissue samples were homogenized and solid-phase extraction was performed on a DSC-18 cartridge. The procedure was used for comparing the effectiveness of the MMC penetration into the urinary bladder tissue by passive diffusion and by intravesical drug electrophoresis. EDMA increases the rate of mitomycin penetration into urinary bladder walls by 3 to 5 times with respect to passive diffusion.     

Electrosurface properties of tungsten(VI) oxide in electrolyte solutions

Electrosurface characteristics of tungsten oxide in solutions of 1: 1 electrolytes are studied in a wide range of concentration and pH values. The dependence of the position of isoelectric point on the concentration of background electrolyte and the cation nature is revealed. The equilibrium constants of surface reactions, adsorption potentials of ions, specific surface conductivities, and degrees of dissociation of surface groups in the point of zero charge are calculated.     

Complex chromatographic determination of the adulteration of dairy products: A new approach

A new approach to complex chromatographic determination of the adulteration of dairy products was proposed, based on the determination of not only the total fatty acid composition but also the composition of the sterol fraction and the concentration of trans-isomers of fatty acids. Procedures for the chromatographic identification of low-fat dairy products were developed, including the extraction of a water-milkalcohol emulsion with a hexane-ether mixture followed by the chromatographic determination of the sterol fraction and trans-isomers.     

Two low-cost digital camera-based platforms for quantitative creatinine analysis in urine

In clinical analysis creatinine is a routine biomarker for the assessment of renal and muscular dysfunctions. Although several techniques have been proposed for a fast and accurate quantification of creatinine in human serum or urine, most of them require expensive or complex apparatus, advanced sample preparation or skilled operators. To circumvent these issues, we propose two home-made platforms based on a CD Spectroscope (CDS) and Computer Screen Photo-assisted Technique (CSPT) for the rapid assessment of creatinine level in human urine. Both systems display a linear range (r² = 0.9967 and 0.9972, respectively) from 160 μmol L⁻¹ to 1.6 mmol L⁻¹ for standard creatinine solutions (n = 15) with respective detection limits of 89 μmol L⁻¹ and 111 μmol L⁻¹. Good repeatability was observed for intra-day (1.7–2.9%) and inter-day (3.6–6.5%) measurements evaluated on three consecutive days. The performance of CDS and CSPT was also validated in real human urine samples (n = 26) using capillary electrophoresis data as reference. Corresponding Partial Least-Squares (PLS) regression models provided for mean relative errors below 10% in creatinine quantification.     

Effect of a precursor on the phase composition and particle size of the active component of Ni-ZrO2 catalytic systems for the oxidation of methane into syngas

The effect the method of preparation has on the formation, phase composition, porous structure, and catalytic properties of the 10% Ni-ZrO₂ system during the partial oxidation of methane into syngas is studied. Stages of the formation of catalysts from precursors and the effect the method of preparation has on the phase composition, particle size, and catalytic properties of the active component during the partial oxidation of methane into syngas are investigated by means of synchronous TG-DTG/DSC and X-ray diffraction. The synthesis of a catalyst precursor via coprecipitation is shown to yield a monophase system with high nickel dispersion, catalytic activity, and stability.     

Phase formation in nanocomposites of the C-Pd-Fe system

Metal-carbon nanocomposites consisting of a carbon matrix with dispersed nanosize bimetallic Pd-Fe particles were obtained. It was established that at 500–700°C, the bimetallic particles form a solid solution of iron in palladium. It was concluded that raising the intensity of infrared pyrolysis to 800–1100°C leads to the formation of intermetallic compounds whose composition depends on the temperature of nano-composite fabrication.