12 research outputs found
Terahertz electron-hole recollisions in GaAs/AlGaAs quantum wells: robustness to scattering by optical phonons and thermal fluctuations
Electron-hole recollisions are induced by resonantly injecting excitons with
a near-IR laser at frequency into quantum wells driven by a
~10 kV/cm field oscillating at THz. At K, up to
18 sidebands are observed at frequencies , with . Electrons and holes recollide with
total kinetic energies up to 57 meV, well above the meV
threshold for longitudinal optical (LO) phonon emission. Sidebands with order
up to persist up to room temperature. A simple model shows that LO
phonon scattering suppresses but does not eliminate sidebands associated with
kinetic energies above .Comment: 5 pages, 4 figure
Nanodot-Cavity Electrodynamics and Photon Entanglement
Quantum electrodynamics of excitons in a cavity is shown to be relevant to
quantum operations. We present a theory of an integrable solid-state quantum
controlled-phase gate for generating entanglement of two photons using a
coupled nanodot-microcavity-fiber structure. A conditional phase shift of
is calculated to be the consequence of the giant optical
nonlinearity keyed by the excitons in the cavities. Structural design and
active control, such as electromagnetic induced transparency and pulse shaping,
optimize the quantum efficiency of the gate operation.Comment: 4 pages 3 figure
In-situ heavy oil upgrading by high temperature oxidation through air injection
Air injection has been widely considered as a technology to enhanced heavy oil recovery on account of the heavy oil upgrading caused by high temperature oxidation during this process. This paper aims at exploring the effects of oxidation thermal processing in a porous media at high temperature from 500 to 540℃ which is the high temperature oxidation range of heavy oil known from TG results, and reaction time from 8 to 16 hours for heavy oil upgrading. It was suggested that the viscosity decreased with the temperature and retention time increased due to getting less ring structure seen from IR Spectrum results. It was observed that the viscosity of heavy oil was reduced 1 to 2 orders of magnitude. Besides, the kinetics of heavy oil upgrading were analysed using five pseudo components including HO (C35+), MO (C15 ~ C35), LO (C5 ~ C14), coke, G (gas products) and successfully predicted the products results with an error of 4.34%, and great correlation to Arrhenius equation. The activation energies obtained are in the range of 44 ~ 215 kJ/mol. This work has great value in revealing the mechanisms of high temperature oxidation heavy oil upgrading and assisting heavy oil production
Differential Expression of PKC Isoforms and Their Tumoricidal Activity in Two Macrophage Cell Lines: Involvement of Nitric Oxide-dependent Mechanisms
Evaluation of the experimental project performance assessment mode with the application of descriptive statistical analysis method
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Terahertz electron-hole recollisions in GaAs/AlGaAs quantum wells: robustness to scattering by optical phonons and thermal fluctuations.
Electron-hole recollisions are induced by resonantly injecting excitons with a near-IR laser at frequency fNIR into quantum wells driven by a 10  kV/cm field oscillating at fTHz=0.57  THz. At T=12  K, up to 18 sidebands are observed at frequencies fsideband=fNIR+2nfTHz, with -8≤2n≤28. Electrons and holes recollide with total kinetic energies up to 57 meV, well above the ELO=36  meV threshold for longitudinal optical (LO) phonon emission. Sidebands with order up to 2n=22 persist up to room temperature. A simple model shows that LO phonon scattering suppresses but does not eliminate sidebands associated with kinetic energies above ELO
Parameters Optimization for Compressing a Mixture of Decomposed Rice Straw and Biochar into a Seedling-raising Mat
Transplanting is the prime growing pattern for rice production, and seedling raising is an essential step of the process. However, the massive soil source and the complicated treatments needed for seedling raising are major issues. This study explored the possibility of using compressed-decomposed rice straw and biochar from rice husk into a seedling-raising mat, to replace the soil and simplify the seeding process. A quadratic rotation-orthogonal combination experiment was conducted to investigate the effect of moisture content, pressure, and residence time on the formation of seedling-raising mat. The regression models between the compressing indicators and the process factors were established. The results showed that the following factors had significant effect on bending strength of the formed mat (P 0.05). The process parameters for compression were optimized and verified using Design-Expert software 8.0.6. The optimized parameters were moisture content of 33%, pressure of 23.0 MPa, and residence time of 61 s. The prediction error is less than 6% under this condition. The results may provide a reference for biomass seedling-raising mat compression