The Pentaneand Toluene-Soluble Fractions of a Petroleum Residue and three Coal Tars by Size Exclusion Chromatography and UV-Fluorescence Spectroscopy — A petroleum atmospheric pressure distillate residue and three tars derived from different coals using different severities of thermal treatment were separated into seven fractions using column chromatography on silica and sequential elution by t...

A progression of induration, erosion, and redeposition of transverse and networked transverse aeolian ridges (TARs) has been documented in the Medusae Fossae Formation (MFF), Mars. Cratered and eroded aeolian bedforms are rarely observed on Mars, indicating that those found in the MFF have been inactive for much longer than those found elsewhere. Indurated TARs are observed to grade into facete...

Escherichia coli and Salmonella typhimurium are closely related species. However, E. coli cells show maltose chemotaxis but S. typhimurium cells do not. When an E. coli chemotransducer gene (tarE), the product of which is required for both aspartate and maltose chemotaxis, was introduced by using a plasmid vector into S. typhimurium cells with a defect in the corresponding gene (tarS), the tran...

A one-dimensional kinetic model for steam?oxygen gasification of refuse derived fuel in a bubbling fluidized bed reactor has been developed. The incorporates the reaction network within fluid dynamics to predict waste and tars conversion, gas composition overall performance. was validated by comparing outlet products temperature profile with experimental data from pilot-scale gasifier, operated...

A low SV causes relatively slow pyrolysis conditions at around 600°C, and produces high yields of charcoal 20-30%, large quantities of unburned tars, and a gas with high hydrocarbon content and high tar (volatile) content. A high SV causes very fast pyrolysis, producing less than 10% char-ash at 1050 C and hot gases at 1200-1400 C in the flaming pyrolysis zone. These gases then react with the r...

The effect of factors on the process chemical modification tar with formaldehyde using a sulfuric acid as catalyst has been studied. By experimental results, adequate statistical-mathematical (ESM) model developed. Based this model, optimal values have identified, bringing about penetration value and softening point modified tars. Data predicted basis ESM were compared empirical evidence tars p...

The 2'-hydroxyl group plays fundamental roles in both the structure and the function of RNA, and is the major determinant of the conformational and thermodynamic differences between RNA and DNA. Here, we report a conformational analysis of 2'-OH groups of the HIV-2 TAR RNA by means of NMR scalar coupling measurements in solution. Our analysis supports the existence of a network of water molecul...

The formation of the Tat-protein/TAR-RNA complex is a crucial step in the regulation of human immunodeficiency virus (HIV)-gene expression. To obtain full-length viral transcripts the Tat/TAR complex has to recruit the positive transcription elongation factor complex (P-EFTb), which interacts with TAR through its cyclin T1 (CycT1) component. Mutational studies identified the TAR hexanucleotide ...