We report the design of a bottle-brush polymer whose architecture closely mimics the lubricating protein lubricin. Interaction forces, assessed using a Surface Forces Apparatus (SFA), between two mica surfaces fully covered by the polymer demonstrate that the polymer adopts a loop conformation giving rise to a weak and long-range repulsive interaction force between the surfaces. Under high comp...

Core flood and field tests have demonstrated that decreasing injection water salinity increases oil recovery from sandstone reservoirs. However, the microscopic mechanism behind the effect is still under debate. One hypothesis is that as salinity decreases, expansion of the electrical double layer decreases attraction between organic molecules and pore surfaces. We have developed a method that ...

Objective This study investigated the wear resistance of injection-molded thermoplastic denture base resins using nanoindentation instrument. Materials and methods Six injection-molded thermoplastic denture base resins (two polyamides, two polyesters, one polycarbonate, one polymethylmethacrylate [PMMA]) and a PMMA conventional heat-polymerized denture-based polymer control were tested. Elastic...

Today, by using half of the oil reserves of the world, natural production of oil has decreased drastically. Gas and water injection for maintaining reservoir pressure is not responsive for oil production.At first, we dispersed silica nanoparticles in low salinity and after two weeks, there was no change in its stability. Then we mixed the nanoparticles in low salinity. After a while, we found o...

research in nanotechnology in the petroleum industry is advancing rapidly and an enormous progress in the application of nanotechnology in this area is to be expected. in particular, adding nanoparticles to fluids may drastically benefit enhanced oil recovery and improve well drilling, by changing the properties of the fluid, rocks wettability alteration, advanced drag reduction, strengthening ...

Carbonic anhydrase (CA) activity and relative expression of CA mRNA were measured in the gills of the euryhaline green crab Carcinus maenas in response to eyestalk ablation (ESA), injection of eyestalk extract and exposure to low salinity. For crabs acclimated to 32 p.p.t. salinity, ESA alone resulted in an increase in both CA activity and relative mRNA expression in the posterior, ion-transpor...

The salinity budget in a 3-D numerical model of an estuary is analyzed using isohaline surfaces to define the volume of integration. Such surfaces move with the currents, and as a result of turbulent mixing. The isohaline analysis allows us to clarify the processes which create and destroy water in different salinity classes in the estuary. We find that the estuary naturally divides into three ...

Today, by using half of the oil reserves of the world, natural production of oil has decreased drastically. Gas and water injection for maintaining reservoir pressure is not responsive for oil production.At first, we dispersed silica nanoparticles in low salinity and after two weeks, there was no change in its stability. Then we mixed the nanoparticles in low salinity. After a while, we found o...