Properties of aqueous solutions containing blends of poly-N-vinylformamide with carboxymethyl cellulose of various degrees of ionization and of composite films of these polymers

Rheological properties of mixtures of dilute and moderately concentrated aqueous solutions of poly-N-vinylformamide and carboxymethyl cellulose of various degrees of ionization were studied. Composite film materials were prepared, and their physicomechanical properties and structural organization were studied.     

Study of the interaction between daunorubicin and human serum albumin,and the determination of daunorubicin in blood serum samples

The interactions between daunorubicin and human serum albumin (HSA) were studied using the spectrofluorimetric method. The binding constants of daunorubicin with HSA were obtained at different temperatures. The effects of various metal ions on the binding constants of daunorubicin with HSA were also studied. The optimum conditions of fluorometric determination of daunorubicin were studied and the developed method was successfully applied to the determination of daunorubicin in serum samples.     

Formation of Physical Thermally Reversible Gels in Solutions of Methyl Cellulose in Water and Dimethylacetamide and Properties of Films Thereof

Gelation conditions in solutions of methyl cellulose in water and dimethylacetamide were studied. The gelation mechanisms were studied by X-ray diffraction and photocolorimetry, and their differences in the two systems were revealed. The physicomechanical properties of methyl cellulose films prepared from solutions with preliminary gelation were determined.     

Effect of the modification of aluminosilicate ash microsphere surfaces on physical-mechanical properties of polyurethane foam

The rigid polyurethane foam materials based on ODF-M complex oligoester filled by hollow silicaalumina microspheres with various surface nature were studied. Physical-mechanical properties of the obtained materials were studied.     

Kinetics of Hydrogenation and Oxidation of Benzyl Alcohol in the Presence of Colloid Palladium in situ

The kinetics of hydrogenation and oxidation with molecular oxygen of benzyl alcohol in the presence of colloid palladium in situ were studied. Mechanisms of the reactions studied were proposed.     

Properties of cellulose solutions in methylmorpholine N-oxide containing montmorillonite nanoparticles and of composite films thereof

Rheological properties of moderately concentrated solutions of cellulose in methylmorpholine N-oxide-dimethylformamide mixtures containing hydrophilic montmorillonite nanoparticles were studied. Film composite materials were prepared, and their physicomechanical properties and structural organization were studied.     

Study of physical and thermochemical properties of modified zeolites

The treatment of zeolite with a solution of NaOH at different concentrations creates modified forms of natural zeolites.These modified zeolites exhibit an increased uptake of caesium and a satisfactory uptake of cobalt. The structural changes in the modified zeolites were studied by XRD analysis, which reveals the mineral compositions of the studied materials. The thermodynamic properties of the modified zeolites were studied by means of DTA and thermogravimetry, and the chemical composition too was determined.     

Effect of ZnO nanoparticles on the thermal and mechanical properties of epoxy-based nanocomposite

Effect of ZnO nanoparticles particles on the mechanical properties and the curing behavior of an epoxy nanocomposite were studied. Nanocomposites were prepared using different loadings of pre-dispersed ZnO nanoparticles having an average size of 40 nm. The surface topography and morphology of the nanocomposites were studied using atomic force microscope (AFM). The mechanical properties of nanocomposites were studied using analytical techniques including dynamic mechanical thermal analysis and micro-Vickers hardness. Effects of ZnO nanoparticles on the curing behavior of these nanocomposites were investigated utilizing isothermal and non-isothermal differential scanning calorimeter techniques. In addition, chemical compositions of coatings containing different ZnO nanoparticles contents were studied using a Fourier transform inferred. It was found that, ZnO nanoparticles can effectively influence the mechanical properties of epoxy coating. In addition, lower curing degrees, and therefore crosslinking density of epoxy coating including higher ZnO nanoparticles were obtained. This effect was completely different at low and high loadings of the particles.     

Models of retention of adamantylamidrazones in reversed-phase high-performance liquid chromatography

Rules governing the chromatographic behavior of some amidrazones of the adamantane series were studied under the conditions of reversed-phase high-performance liquid chromatography. The characteristics of the retention of sorbates in elution by aqueous-acetonitrile phases with various compositions were calculated. Correlations between the structure and physicochemical characteristics of sorbate molecules and their retention were studied.     

Synthesis of ultrafine refractory oxides zirconia-hafnia-yttria by sol-gel technology

A transparent gel was prepared using a hydrolytically active solution of zirconium, hafnium, and yttrium alkoxoacetylacetonates. This gel served to synthesize ultrafine zirconia-hafnia-yttria complex oxide. The product dispersity was studied as affected by the parameters of xerogel heat treatment. The thermal behavior of the xerogel was studied by DSC-TGA. Elemental analysis (laser mass spectrometry) and phase analysis of the synthesized materials were carried out. Average crystallite sizes were calculated by the Scherrer relationship. The particle morphology was studied by TEM. Specific surface areas were determined. Sintering of ultrafine oxide powders was studied at 1000, 1200, and 1400°C.     

Complete assignment of (1)H and (13)C NMR data of dihydroxyflavone derivatives

Six flavone derivatives were studied. Previously reported NMR data of three of these derivatives were corrected and the NMR data for the other three derivatives not studied previously were completely assigned on the basis of the basic 1D and 2D NMR experiments and molecular modeling.     

Properties of solutions and films of blends of water-soluble cellulose ethers with Zosterin

Viscosity characteristics of dilute and moderately concentrated solutions of blends of methyl cellulose, hydroxyethyl cellulose, and carboxymethyl cellulose with Zosterin were studied. Composite films were prepared from solutions of the polymer blends; their IR spectra and physicomechanical and thermomechanical properties were studied. The region of thermodynamic compatibility of cellulose ethers with Zosterin was determined by solvent vapor sorption.     

Acid and complex-forming properties of tetrapyrazinoporphyrazines

The reactions of octaethyl- and octaphenyltetrapyrazinoporphyrazines with dimethyl sulfoxide were studied. The compositions of the resulting complexes with proton-transfer were determined. The reaction of the formation of a magnesium(II) octaethyltetrapyrazinoporphyrazine complex in pyridine was studied. Kinetic parameters of the reaction were determined and assumptions on the reaction mechanism were made.     

Modification of Synthetic Latexes with Colloidal Silver

Butadiene-styrene and acrylate latexes were studied as matrices for preparing colloidal silver. Colloidal-chemical and strength properties of the modified latexes and Primal E1950 latex films were studied. The heat resistance of these materials was determined.     

Influence of Thermal Aging Conditions on the Molecular Characteristics of Cellulose and Mechanical Properties of Paper Thereof

Molecular characteristics of cellulose during accelerated aging were studied over wide temperature and time ranges. Also studied were mechanical properties of model samples of paper made of cotton, sulfate, and sulfite cellulose. Interrelation of the molecular characteristics of cellulose and strength properties of paper was investigated.     

Spectroscopic (FT-IR, FT-Raman, UV) and microbiological studies of di-substituted benzoates of alkali metals

The FT-IR, FT-Raman and UV spectra of 3,5-dihydroxybenzoic and 3,5-dichlorobenzoic acids as well as lithium, sodium, potassium, rubidium, caesium 3,5-dihydroxy- and 3,5-dichlorobenzoates were recorded, assigned and compared. The theoretical geometries, Mulliken atomic charges, IR wavenumbers were obtained in B3LYP/6-311++G** level. On the basis of the gathered experimental and theoretical data the effect of metals and substituents on the electronic system of studied compounds were investigated. Moreover, the antimicrobiological activity of studied compounds against two species of bacteria: Bacillus subtilis, Staphylococus aureus and one species of yeast: Candida albicans were studied after 24 and 48 h of incubation. The attempt was made, to find out whether there is any correlation between the first principal component and the degree of growth inhibition exhibited by studied compounds in relation to selected microorganisms.     

含两个磷原子三稠环系三唑磷茂啉衍生物的反应选择性

当同一三稠环系三唑磷茂啉化合物中含有两个不同的磷原子时,它们不仅在光谱性质上有差别,而且在化学反应中的反应活性也不相同。本文报道三稠环系三唑磷茂啉化合物中环内磷与环外磷在硫化反应和亲核反应巾的选择性。     

用离子交换/ICP-AES联用技术研究溶液中配合铝的形态及分布

以阳离子交换微柱分离与ICP-AES检测联用技术为分离/检测手段,系统地研究了不同配体配合物体系中铝的形态及其分布.当pH=6.0时,溶液中非稳定态单核铝被微柱所保留,而稳定态配合铝直接从微柱中流出.所选择的研究体系分别为:Al-氟化物(Al-Fluoride),Al-磷酸盐(Al-Phosphate),Al-柠檬酸盐(Al-Citrate),Al-草酸盐(Al-Oxalate)及Al-EDTA.在确定的pH值条件下,研究了不同的摩尔比[n(Al)/n(配合剂)]对铝的形态分布的影响,得到了一些对实际应用有指导意义的规律性结论.     

Complete assignment of 1H and 13C NMR data of some flavonol derivatives

Nine flavonol derivatives were studied. Previously reported NMR data of three of these derivatives were corrected. We report complete assignments of the NMR data for six flavonol derivatives not previously studied.     

Thermal characteristics of the combustion process of biomass and sewage sludge

The combustion of two kinds of biomass and sewage sludge was studied. The biomass fuels were wood biomass (pellets) and agriculture biomass (oat). The sewage sludge came from waste water treatment plant. The biomass and sludge percentage in blends with coal were 10 %. The studied materials were characterised in terms of their proximate and ultimate analysis and calorific value. The composition of the ash of the studied fuels was also carried out. The behaviour of studied fuels was investigated by thermogravimetric analysis (TG, DTG and DTA). The samples were heated from an ambient temperature up to 1,000 °C at a constant three rates: 10, 40 and 100 °C min^?1 in 40 mL min^?1 air flow. TG, DTG and DTA analysis showed differences between coal, biomass fuels and sewage sludge. 10 % addition of studied fuels to the mixture with coal changed its combustion profile in the case of sewage sludge addition. The combustion characteristics of fuel mixtures showed, respectively, qualitative summarise behaviour based on single fuels. Evolved gaseous products from the decomposition of studied samples were identified. This study showed that thermogravimetric analysis connected with mass spectrometry is useful techniques to investigate the combustion and co-combustion of biomass fuels, and sewage sludge, together with coal. Non-isothermal kinetic analysis was used to evaluate the Arrhenius activation energy and the pre-exponential factor. The kinetic parameters were calculated using Kissinger–Akahira–Sunose model.