We present a method of adiabatically changing the local phase-space density of an ultracold gas using a combination of magnetic and optical forces. Applying this method, we observe phase-space density increases in a gas of sodium atoms by as much as 50-fold. The transition to Bose-Einstein condensation was crossed reversibly, attaining condensate fractions of up to 30%. Measurements of the cond...

In the oil and gas production process, apart from hydrocarbons, a number of impurities are produced, including CO2 sulfur in various concentrations, depending on conditions characteristics reservoir location where is located. To process removal condensate, common technology HDS (Hydrodesulfurization). However, with requirements such as high temperature, pressure, intensive hydrogen consumption,...

Hydrocarbon production from unconventional resources and the use of reservoir stimulation techniques, such as hydraulic fracturing, has grown explosively over the last decade. However, concerns have arisen that reservoir stimulation creates significant environmental threats through the creation of permeable pathways connecting the stimulated reservoir with shallower freshwater aquifers, thus re...

A fundamental property of a three-dimensional Bose-Einstein condensate is long-range coherence; however, in systems of lower dimensionality, not only is the long-range coherence destroyed but additional states of matter are predicted to exist. One such state is a "transverse condensate," first predicted by van Druten and Ketterle [Phys. Rev. Lett. 79, 549 (1997)], in which the gas condenses in ...

We extend our recent work on the two-fluid hydrodynamics of the condensate and non-condensate in a trapped Bose gas by including the dissipation associated with viscosity and thermal conduction. For purposes of illustration, we consider the hydrodynamic modes in the case of a uniform Bose gas. A finite thermal conductivity and shear viscosity give rise to a damping of the first and second sound...

withdrawal of oil and gas from reservoirs causes a decrease in pore pressure and an increase in effective stress which results to a reservoir compaction. reservoir compaction will result in surface subsidence through the elastic response of the subsurface. usually in order to determine the subsidence above a hydrocarbon field, the reservoir compaction must be first calculated and then the effec...

Xu deep volcanic gas reservoir is typical of complex lithology, severe inhomogeneity, big difficulty to extract. Pressure sensitivity always exists in gas reservoirs. Prorating production is too high or low, causing problems, as for the energy loss, reservoir damage, bottom effusion, thus lowing the gas productivity and affecting development benefit. So it have to research on a new reasonably p...

since the pressure of hydrocarbon reservoirs drops due to production, in order to keep the production rate constant or increase enhanced recovery, few methods are used. one of which is gas injection to the reservoir. on the other hand, due to reduction in oil production potential of aghajari oil field, gas injection is highly required to pressurize and enhance oil recovery. there is a possibili...

We have observed the Bose-Einstein condensation of an atomic gas in the (quasi)uniform three-dimensional potential of an optical box trap. Condensation is seen in the bimodal momentum distribution and the anisotropic time-of-flight expansion of the condensate. The critical temperature agrees with the theoretical prediction for a uniform Bose gas. The momentum distribution of a noncondensed quan...