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The article presents the results of measurement of the thermal conductivity of water–petroleum emulsions of direct and reverse types at a pressure of up to 20 MPa in the temperature range 293–353 K during the change of up to 50 vol.% in the volume content of the dispersed phase in the emulsion. The previously obtained correlation is suitable for determining the thermal conductivity of water–petroleum emulsions of direct and reverse types in a wide range of changes in the content of dispersed phase and of temperature and pressure parameters. [ABSTRACT FROM AUTHOR]

A correlation for calculating the thermal conductivity of binary dispersed systems depending on their composition is proposed. The results of measuring the thermal conductivity of reverse type water-in-oil emulsions at a pressure of up to 20 MPa in the temperature range of 293–353 K with a change in the volumetric water content in the emulsion up to 50% are presented. The obtained correlation is suitable for calculation of the thermal conductivity of water-in-oil emulsions in a wide range of changes of water content, temperature and pressure. [ABSTRACT FROM AUTHOR]

The results of a study of the phase behavior of six narrow oil fractions in the 150-350 K temperature range at atmospheric pressure using scanning calorimetry are presented. It is shown that there is a correlation between glass transition of the studied oil fractions and their mean boiloff temperature, molecular mass, and initial oil viscosity. [ABSTRACT FROM AUTHOR]

The results of measuring the thermophysical and acoustic properties of four samples of natural oils in the temperature range 293–353 K at atmospheric pressure are presented. The correlation between thermophysical and acoustic properties in oils is shown. The correlation indicates the possibility of applying the concepts of heat transfer in complex hydrocarbon systems through hyper-sonic sound motions, taking into account their absorption and scattering by density fluctuations. [ABSTRACT FROM AUTHOR]

The repowering project of the Nizhnekamsk CHPP involves upgrading the main and accessory boiler equipment to allow flame combustion of pulverized petroleum coke (petcoke) produced by a TANEKO delayed coking unit. The scope of work includes equipping the gas-and-oil fired boiler with a burner arrangement for petcoke combustion and providing central coal pulverization and pneumatic ash handling. To meet the atmospheric emission requirements, it is necessary to equip the boilers with a selective catalytic reduction installation, high-efficiency electrostatic precipitators, and a desulfurization plant. [ABSTRACT FROM AUTHOR]

The modernization program of the Moscow Oil Refinery includes a proposal to create an Advanced Oil Refining Complex that comprises the construction of flexicoking processing units and a power generation unit operating with flexigas, a low-calorific gas formed in the process of flexicoking. This will make it possible to reduce the demand for steam and electric power from external networks. An analysis of the currently functioning and future demands of the Moscow Oil Refinery for energy resources and estimation of existing energy sources for the plant is performed, requirements imposed on the power generation unit are determined, current flexigas firing technologies are reviewed, the choice of an optimal variant configuration of the power generation unit is evaluated, and the principal technical decisions for the equipment of the power generation unit are presented. [ABSTRACT FROM AUTHOR]

Carbonylation of acetylenic alcohols in the presence of Pd-black and cobalt carbonyl leads to derivatives of alkylidenesuccinic acids in yield of ∼50%. [ABSTRACT FROM AUTHOR]

The dynamics of allele frequency of the carboxiesterase gene, the frequency of sex-linked lethal mutations, and recombination events in natural populations of Drosophila melanogaster from Odesa were studied. All studied estimates were shown to remain unchanged in June, July, and August during the 2009 collection season. [ABSTRACT FROM AUTHOR]

The article discusses the findings of a study which examined the effects of crystallization and vitrification in petroleum system. The system consists of a high-molecular-weight amorphous matrix in which easily crystallized components of different molecular weight and composition are dissolved. The glass transition of the system begins both before and after completion of crystallization.

The results of measuring the thermophysical properties of Kumkol' crude oil, which contains many easily crystallized waxes, by the hot wire method at different pressures and differential scanning calorimetry at atmospheric pressure are reported. The results are compared. Wide crystallization ranges were found and the temperatures of the transition to the glassy state were determined. The curves of these transitions were plotted. The hypothesis that crystallization of waxes does not prevent further the glass transition of cuts remaining in the liquid state is confirmed. [ABSTRACT FROM AUTHOR]

The effect of a magnetic field on the stability of null domain walls is considered in terms of a variational model. The walls are localized near defects in a (001)-oriented plate. The critical fields at which the inhomogeneities exist are found, and their role in magnetization processes taking place in the crystals under study is considered. [ABSTRACT FROM AUTHOR]

In this computational work we study complexes with two equivalent intermolecular hydrogen bonds formed between trimethyl phosphine oxide and two identical proton donors ("twin" hydrogen bonds) for a set of 70 proton donor molecules. The changes in the phosphorus chemical shift and stretching frequency of the P＝O group upon complexation correlate quite well with the total strength of two hydrogen bonds. A set of explicit numerical dependences is proposed for assessing interatomic distances and hydrogen bond strengths from spectral data. Comparison with the results obtained for analogous previously studied 1 : 1 complexes allowed us to analyze in detail anticooperativity effects on the geometry, energy and spectral parameters. Two hydrogen bonds compete for the PO acceptor group and their mutual weakening increases nonlinearly with the strengthening of the complex, reaching approximately 25% in energy (which corresponds to 0.1 Å lengthening for short strong H-bonds), which is clearly seen in NMR and IR spectra and correlates well with the changes in the spectral parameters. [ABSTRACT FROM AUTHOR]

The long non-coding RNA HOTAIR is overexpressed in many cancers and is associated with several cancer-promoting effects, including increased cell proliferation, migration and treatment resistance. HOTAIR levels correlate with tumor stage, lymph node metastasis and overall survival in patients with various types of cancer. This highlights the potential uses of HOTAIR, including early cancer detection, predicting patient outcome, identifying high-risk individuals and assisting in therapy selection and monitoring. The aim of this review is to provide a comprehensive summary of the research progress, molecular mechanisms and clinical significance of HOTAIR in various human cancers. In addition, the clinical applications of HOTAIR, such as targeted therapy, radiotherapy, chemotherapy and immunotherapy, are discussed, and relevant information on the potential future advances of HOTAIR in cancer research is provided. [ABSTRACT FROM AUTHOR]

A number of dienic mono- δ-dimethylamino ketones, containing a macrocylic fragment, was synthesized by the condensation of 1,1,3-trimethoxy-3-dimethylaminopropane and β-dimethylaminoacrolein acetal aminal with macrocylic ketones. We were unable to obtain polyenic bis- δ,δ′-dimethylamino ketones, containing a macrocyclic fragment, by this route. [ABSTRACT FROM AUTHOR]

The main direction in the acylation of monosubstituted and disubstituted alkynes by 1-methyl-Δ-cyclohexenecarbonylt tetrafluoroborate is the formation of bicyclo[3.3.1]nonene derivatives. [ABSTRACT FROM AUTHOR]

A method was proposed for the preparation of functionally substituted α-formyl-β-akloylcyclopentanes from the photoaddition products of 2-cyclopentenone to 1-alkynes. [ABSTRACT FROM AUTHOR]

Acylation of alkynes with α- or β-bromoacylium tetrafluoroborates forms substituted Z- β-bromovinyl ketones as a result of the conjugate addition of the acylium cation and 1,4- or 1,5-bromine migration from the acyl group. [ABSTRACT FROM AUTHOR]

The acylation of alkynes by α-bromobutyroyl tetrafluoroborate under 'nonnucleophilic' conditions takes place as a reaction involving the conjugated addition of the acylium cation and the bromide anion from the acyl residue over the triple bond by means of a 1, 4 shift. [ABSTRACT FROM AUTHOR]

Acylation of alkenes with branching at the allylic carbon provides a preparative route to cyclic carboxonium salts. Such salts can be prepared by protonation of β, γ-unsaturated ketones -the products of acylation of unbranched alkenes. We have examined the mechanism of acylation of acylium salts. [ABSTRACT FROM AUTHOR]

Acyclic and cyclic alkoxypolymethine salts are synthesized via alkylation of unsaturated bis(ω′-dimethylamino) ketones. [ABSTRACT FROM AUTHOR]

We have examined the condensation of 1,1,3-trimethoxy-3-dimethylaminopropane with cyclic and heterocyclic ketones and with enaminoketones; we have synthesized a series of unsaturated ω-dimethylamino and ω, ω-bis(dimethylamino) ketones, which the PMR spectra indicate as having the trans configuration of the methine protons and to exist as the S-trans conformers about the β, γ-bond. [ABSTRACT FROM AUTHOR]

During irradiation in methanol by light with λ ≥ 300 nm, 7-amyl- and 6-amylbicyclo[3.2.0]hept-6-en-2-ones rearrange into derivatives of bicyclo[2.2.1]heptene with the simultaneous addition of the solvent. [ABSTRACT FROM AUTHOR]

The acylation of arylacetylenes by cationoid reagents in the presence of aromatic hydrocarbons proceeds as a reaction of stereospecific trans-addition, and leads to a high yield of β, β-diarylvinyl ketones with a strictly fixed configuration of the aromatic groups. [ABSTRACT FROM AUTHOR]

A method was proposed for the synthesis of the acetals of di- and tricyclopropane aldehydes. [ABSTRACT FROM AUTHOR]

Some previously unknown triamines and hydroxyamines of the acetylenic series have been synthesized via Mannich-type aminomethylation. [ABSTRACT FROM AUTHOR]