We investigate the acoustic and mechanical properties of a reservoir sandstone saturated by two immiscible hydrocarbon fluids, under different saturations and pressure conditions. The modeling of static and dynamic deformation processes in porous rocks saturated by immiscible fluids depends on many parameters such as, for instance, porosity, permeability, pore fluid, fluid saturation, fluid pre...

In case of porous fluid-saturated medium the Biot’s poroelasticity theory predicts a movement of the pore fluid relative to the skeleton on seismic wave propagation through the medium. This phenomenon opens an opportunity for investigation of the flow properties of the hydrocarbon-saturated reservoirs. It is well known that relative fluid movement becomes negligible at seismic frequencies if po...

The lake and bog deposits of Cedar Creek Forest, Isanti and Anoka counties, Minnesota, consist of a multiple-facies accumulation of marl, peat, copropel, and sapropel. Chromatographic analyses of the lipoid extracts of samples of the sediments show measurable amounts of saturated and aromatic hydrocarbons as well as large proportions of asphalts and polar lipoid compounds. In general compositio...

Chemistry by computer provides access to microsystem information not readily achieved by other means. Simple computational analysis of saturated triglyceride polymorphism by molecular mechanics within constraints provided by X -ray data show that polymethylene interactions determine hydrocarbon crystal properties when they account for more than 60 percent of the total molecular interaction ener...

The composition of the lipid matrix is critical for function of membrane proteins. Perhaps one of the best studied examples is the function of the G-protein-coupled membrane receptor (GPCR) rhodopsin which is located in membranes with high content of phospholipids with polyunsaturated docosahexaenoic acid chains (DHA, 22:6n-3). Technological advances enabled a more detailed study of structure a...

The data obtained from the ESR experiments show a complex, depth dependent effect of CoQ10 on the lipid molecules mobility in the bilayer. These effects depend both on its concentration and the temperature. CoQ10 disturbs not only the hydrophobic core of the membrane but also the region close to the hydrophilic headgroups of phospholipids. Both these effects could be explained by the fact that ...

A Monte Carlo dynamics (MCD) scheme has been applied in a study of the effects of unsaturated double bonds on the internal conformational dynamics and orientational order of hydrocarbon chains arranged in a monolayer on the surface of an impenetrable interface. The MCD algorithm makes use of the high coordination {2 1 0) lattice for the representation of both sp3 and sp2 valence states of the c...

Lubell proved this by observing that the left-hand side is a probability: it is simply the probability that a maximal chain, chosen uniformly at random, intersects A. The LYM inequality implies that an antichain in P([n]) has size at most ( n bn/2c ) , the size of the ‘middle layer’ in P([n]). (This can also be proved by partitioning P([n]) into ( n bn/2c ) disjoint chains.) Bollobás’ Inequalit...

lurestan province is petroliferous area. the reserved oil are in ilam and sarvak  (cretaceous ) and kangan ( lower triassic ) and dalan (permian) formations. the lurestan area had high exploration activity but contribution of source rocks in hydrocarbon accumulations isn’t clear. in this paper essential elements and process of hydrocarbon accumulation are introduced. candidate  source  rocks ar...

Phosphatidycholines (PC) with two saturated acyl chains (e.g., dipalmitoyl) mimic natural sphingomyelin (SM) by promoting raft formation in model membranes. However, sphingoid-based lipids, such as SM, rather than saturated-chain PCs have been implicated as key components of lipid rafts in biomembranes. These observations raise questions about the physical packing properties of the phase states...