Tectonic controls on residual oil saturation below the present-day fluid contact level in reservoirs of the Persian Gulf

Acknowledgments The authors would like to acknowledge, and gratefully appreciate the support of, the Aberdeen Formation Evaluation Society for their sponsorship, and Emerson (Paradigm) for providing the Geology software for the development of this study.Peer reviewedPostprin

The effect of rock type on natural water flooding and residual oil saturation below free water level and oil water contact : A case study from the Middle East

Acknowledgments The authors would like to gratefully acknowledge and appreciate the support of Aberdeen Formation Evaluation Society (AFES) and Baker Hughes for their sponsorship and Emerson for providing Geolog software for development of this study.Peer reviewedPostprin

Correlation induced phonon softening in low density coupled bilayer systems

We predict a possible phonon softening instability in strongly correlated coupled semiconductor bilayer systems. By studying the plasmon-phonon coupling in coupled bilayer structures, we find that the renormalized acoustic phonon frequency may be softened at a finite wave vector due to many-body local field corrections, particularly in low density systems where correlation effects are strong. We discuss experimental possibilities to search for this predicted phonon softening phenomenon.Comment: 4 pages with 2 figure

Heterogeneous T cell receptor Vβ gene repertoire in murine interstitial nephritis

Anti-tubular basement membrane disease (alpha TBM) produces T cell-mediated interstitial nephritis in SJL/J mice following immunization with heterologous renal tubular antigen. Initial mononuclear infiltrates appear in vivo after six to eight weeks, with subsequent progression to renal fibrosis and endstage kidney disease. Cultured lymph node derived nephritogenic T cells from these mice react to a small epitopic region of the 3M-1 target antigen and share a common amino acid motif in their V beta CDR3 regions. We now have used RT-PCR to further characterize the renal expression of T cell receptor (TcR) V beta gene repertoires during the course of this disease. Individual kidneys with focal mononuclear infiltrates characteristic of early alpha TBM disease express up to three different TcR V beta genes; however, the same V beta genes are not found in all kidneys at the same early stage of injury. DNA sequencing of the V beta RT-PCR products reveals a heterogeneous population of VDJ recombinations and deduced CDR3 amino acid sequences. Our studies do not support TcR V beta region gene restriction in histologically-detectable alpha TBM disease, but are more consistent with a dynamic, organ-specific autoimmune disease, directed at multiple autoantigenic epitopes

Many-body correlations probed by plasmon-enhanced drag measurements in double quantum well structures

Electron drag measurements of electron-electron scattering rates performed close to the Fermi temperature are reported. While evidence of an enhancement due to plasmons, as was recently predicted [K. Flensberg and B. Y.-K. Hu, Phys. Rev. Lett. 73, 3572 (1994)], is found, important differences with the random-phase approximation based calculations are observed. Although static correlation effects likely account for part of this difference, it is argued that correlation-induced multiparticle excitations must be included to account for the magnitude of the rates and observed density dependences.Comment: 4 pages, 3 figures, revtex Accepted in Phys. Rev.

HASH(0x563d44119a80)

HASH(0x563d43e27db0)HASH(0x563d44003f78

A microfabricated sensor for thin dielectric layers

We describe a sensor for the measurement of thin dielectric layers capable of operation in a variety of environments. The sensor is obtained by microfabricating a capacitor with interleaved aluminum fingers, exposed to the dielectric to be measured. In particular, the device can measure thin layers of solid frozen from a liquid or gaseous medium. Sensitivity to single atomic layers is achievable in many configurations and, by utilizing fast, high sensitivity capacitance read out in a feedback system onto environmental parameters, coatings of few layers can be dynamically maintained. We discuss the design, read out and calibration of several versions of the device optimized in different ways. We specifically dwell on the case in which atomically thin solid xenon layers are grown and stabilized, in cryogenic conditions, from a liquid xenon bath

Dynamic correlations in symmetric electron-electron and electron-hole bilayers

The ground-state behavior of the symmetric electron-electron and electron-hole bilayers is studied by including dynamic correlation effects within the quantum version of Singwi, Tosi, Land, and Sjolander (qSTLS) theory. The static pair-correlation functions, the local-field correction factors, and the ground-state energy are calculated over a wide range of carrier density and layer spacing. The possibility of a phase transition into a density-modulated ground state is also investigated. Results for both the electron-electron and electron-hole bilayers are compared with those of recent diffusion Monte Carlo (DMC) simulation studies. We find that the qSTLS results differ markedly from those of the conventional STLS approach and compare in the overall more favorably with the DMC predictions. An important result is that the qSTLS theory signals a phase transition from the liquid to the coupled Wigner crystal ground state, in both the electron-electron and electron-hole bilayers, below a critical density and in the close proximity of layers (d <~ r_sa_0^*), in qualitative agreement with the findings of the DMC simulations.Comment: 13 pages, 11 figures, 2 table

Effects of density imbalance on the BCS-BEC crossover in semiconductor electron-hole bilayers

We study the occurrence of excitonic superfluidity in electron-hole bilayers at zero temperature. We not only identify the crossover in the phase diagram from the BCS limit of overlapping pairs to the BEC limit of non-overlapping tightly-bound pairs but also, by varying the electron and hole densities independently, we can analyze a number of phases that occur mainly in the crossover region. With different electron and hole effective masses, the phase diagram is asymmetric with respect to excess electron or hole densities. We propose as the criterion for the onset of superfluidity, the jump of the electron and hole chemical potentials when their densities cross.Comment: 4 pages, 3 figure