Исследование состава озонобезопасного фреона ФОЛ-62 хроматомасс-спектральным методом.

By chromatography-mass spectrometry composition of ozonesafe freon FOL-62 obtained by method of fluorination with depleted uranium hexafluoride UF6 has been investigated.Методом хроматомасс-спектрометрии изучен состав озонобезопасного фреона ФОЛ-62, полученного фторированием обедненным гексафторидом урана UF6

Анализ эффективности очистки HEX-олигонуклеотидов, полученных с использованием модифицированного метода деблокирования

A new way of deblocking of synthetic hexachlorofluorescein-oligodeoxyribonucleotides (HEX-ODN) prevents the modification of the label and the accumulation of difficult to separated by-product. It was shown that this method increases the efficiency of purification HEX-ON and the sensitivity of DNA diagnostics.Новый способ деблокирования синтетических гексахлорфлуоресцеин-олигодезоксирибонук-леотидов (HEX-ODN) препятствует модификации метки и накоплению трудно отделяемого побочного продукта. Показано, что его применение увеличивает эффективность очистки HEX-ODN и чувствительность ДНК-диагностики

Polarization Effects in Exclusive Hyperon Production Reactions

This research was sponsored by the National Science Foundation Grant NSF PHY-931478

Investigation of ozonesafe freon FOL-62 composition by chromatography-mass spectrometry method.

By chromatography-mass spectrometry composition of ozonesafe freon FOL-62 obtained by method of fluorination with depleted uranium hexafluoride UF6 has been investigated

Crystallization and preliminary crystallographic analysis of the hydroxyquinol 1,2-dioxygenase from Nocardioides simplex 3E: a novel dioxygenase involved in the biodegradation of polychlorinated aromatic compounds

Hydroxyquinol 1,2-dioxygenase (HQ1,2O) from Nocardioides simplex 3E, an enzyme involved in the aerobic biodegradation of a large class of chloroaromatic compounds such as 2,4-dichlorophenoxyacetate (2,4-D) and 2,4,5-trichlorophenoxyacetate (2,4,5-T), has been crystallized. HQ1,2O, which specifically catalyzes the intradiol cleavage of hydroxyquinol (1,2,4-trihydroxybenzene), an intermediate in the degradation of a variety of aromatic pollutants, to maleylacetate, has been recently purified to homogeneity. The enzyme is an homodimer composed of two identical subunits in a alpha(2)-type quaternary structure, has a molecular weight of about 65 kDa and contains a catalytically essential Fe(III) ion. Crystals of HQ1,2O obtained using 2% PEG 400 and 2 M ammonium sulfate at pH 7.5 as precipitants belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 81.15(6), b = 86.79(7), c = 114.93(8). Assuming one dimer per asymmetric unit, the V-m value is 2.51 Angstrom(3) Da(-1). A complete native data set to 1.8 Angstrom resolution has been collected on a laboratory source. This is the first intradiol dioxygenase which specifically catalyzes the cleavage of hydroxyquinol to give diffraction-quality crystals

Analysis of efficiency of purification of HEX-oligonucleotides obtained by modified deblocking

A new way of deblocking of synthetic hexachlorofluorescein-oligodeoxyribonucleotides (HEX-ODN) prevents the modification of the label and the accumulation of difficult to separated by-product. It was shown that this method increases the efficiency of purification HEX-ON and the sensitivity of DNA diagnostics

On the room temperature multiferroic BiFeO 3: magnetic, dielectric and thermal properties

Magnetic dc susceptibility between 1.5 and 800 K, ac susceptibility and magnetization, thermodynamic properties, temperature dependence of radio and audio-wave dielectric constants and conductivity, contact-free dielectric constants at mm-wavelengths, as well as ferroelectric polarization are reported for single crystalline BiFeO3. A well developed anomaly in the magnetic susceptibility signals the onset of antiferromagnetic order close to 635 K. Beside this anomaly no further indications of phase or glass transitions are indicated in the magnetic dc and ac susceptibilities down to the lowest temperatures. The heat capacity has been measured from 2 K up to room temperature and significant contributions from magnon excitations have been detected. From the low-temperature heat capacity an anisotropy gap of the magnon modes of the order of 6 meV has been determined. The dielectric constants measured in standard two-point configuration are dominated by Maxwell-Wagner like effects for temperatures T > 300 K and frequencies below 1 MHz. At lower temperatures the temperature dependence of the dielectric constant and loss reveals no anomalies outside the experimental errors, indicating neither phase transitions nor strong spin phonon coupling. The temperature dependence of the dielectric constant was measured contact free at microwave frequencies. At room temperature the dielectric constant has an intrinsic value of 53. The loss is substantial and strongly frequency dependent indicating the predominance of hopping conductivity. Finally, in small thin samples we were able to measure the ferroelectric polarization between 10 and 200 K. The saturation polarization is of the order of 40 μC/cm2, comparable to reports in literature