Introduction: The possible existence of water ice in permanently shadowed regions near the lunar poles has been postulated by Watson et al. [1]. The delivery rate of water into the cold lunar polar craters due to degassing from the lunar interiors, micrometeorite bombardment, solar wind, and comet impacts was investigated [2]. Some experiments have been made to search for the existence of water...

Determining oil migration distances from source rocks to reservoirs can greatly help in the search for new petroleum accumulations. Concentrations and ratios of polar organic compounds are known to change due to preferential sorption of these compounds in migrating oils onto immobile mineral surfaces. However, these compounds cannot be directly used as proxies for oil migration distances becaus...

RATIONALE Characterising complex mixtures of organic compounds in polar fractions of heavy petroleum is challenging, but is important for pollution studies and for exploration and production geochemistry. Oil sands process-affected water (OSPW) stored in large tailings ponds by Canadian oil sands industries contains such mixtures. METHODS A polar OSPW fraction was obtained by silver ion solid...

The differential solubility of polar and apolar groups in water is important for the self-assembly of globular proteins, lipid membranes, nucleic acids, and other specific biological structures through hydrophobic and hydrophilic effects. The increase in water's heat capacity upon hydration of apolar compounds is one signature of the hydrophobic effect and differentiates it from the hydration o...

There is no other naturally occurring defense agent against cancer that has a stronger effectthan paclitaxel, commonly known under the brand name of Taxol®. The major drawback for themore widespread use of paclitaxel and its precious precursor, 10-deacetylbaccatin III (10-DABIII), is that they require large-scale extraction from different parts of yew trees (Taxus species),cell cultures, taxane...

RATIONALE A considerable fraction of atmospheric particulate fine matter consists of organosulfates, with some of the most polar ones originating from the oxidation of isoprene. Their structural characterization provides insights into the nature of gas-phase precursors as well as into formation pathways. METHODS The structures of unknown polar organosulfates present in ambient particulate fin...

the present study was conducted to determine the relative contribution of initial quality and compositional parameters to the rate of changes (rctpc) in the content of total polar compounds (tpc), which is considered to be one of the most reliable indicators of heated oils quality, of olive oil during continuous heating at 180 ºc. the ratio between monounsaturated and polyunsaturated fatty acid...

cyclodextrins (cds) are a family of cyclic oligosaccharides which are composed of α (1,4) -linked glucopyranose subunits. thebest-characterized forms are α, β and γ cd which are consisted of six, seven and eight d-glucose units, respectively. cyclodextrins are produced from starch by enzymatic degradation. these macrocyclic carbohydrates with polar internal cavities can form complexes with and ...

We have conducted a systematic evaluation of the calculated molecular properties of compounds in clinical development and have found that the development process selects for compounds that have certain computed physical properties. In particular, as the stage of development progresses, compounds that are advanced have lower calculated octanollwater partition coefficient (ClogP), polar surface a...

The cuticular lipid compounds, usually named waxes, present in the layering of Quercus suber adult leaves were extracted with solvents different polarities (n-hexane, dichloromethane and acetone) analysed by GC–MS. Q. have a substantial wax layer (2.8% leaf mass 239 μg/cm2), composed predominantly terpenes (43–63% all compounds), followed aliphatic long chain molecules, mainly fatty acids, smal...