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L K Ang

Publications and source records attributed to L K Ang.

4 recordsLinked to original sources
PubMed2003

New scaling of child-langmuir law in the quantum regime.

This paper presents a consistent quantum mechanical model of Child-Langmuir (CL) law, including electron exchange-correlation interaction, electrode's surface curvature, and finite emitter area. The classical value of the CL law is increased by a larger factor due to the electron tunneling through the space-charge potential, and the electron exchange-correlation interaction becomes important when the applied gap voltage Vg and the gap spacing D are, respectively, on the order of Hartree energy level, and nanometer scale. It is found that the classical scaling of Vg(3/2) and D(-2) is no longer valid in the quantum regime, and a new scaling of Vg(1/2) and D(-4) is established. The smooth transition from the classical regime to the quantum regime is also demonstrated.

Journal Article↗
PubMed2001

Limiting current density in a crossed-field nanogap.

Using a mean-field theory, we have studied the quantum extension on the limiting current density in a crossed-field nanogap. When the gap spacing is less than the electron wavelength, our results show that the limiting current density is increased by a large factor from the classical values due to the effects of electron tunneling. The effects of the external magnetic field diminish with a decrease of gap spacing. Smooth transition from the classical regime to the quantum regime is demonstrated.

Journal Article↗
PubMed1995

Effects of ethanol on peripheral benzodiazepine binding sites in the mouse cerebellum and brain stem.

[3H]PK 11195 binding to the peripheral benzodiazepine binding site was investigated in the brain and liver of mice treated with ethanol (4 g/kg, p.o.) daily for 5 days. In the brain stem, Bmax was decreased by 78% in the ethanol-treated group with unaltered Kd (2 nM). The ethanol-withdrawn group did not differ from the control group in both parameters. In the cerebellum, Bmax was decreased by 74% but the binding affinity increased 5-fold as the Kd decreased from 10 to 2 nM. The ethanol-withdrawn group did not differ significantly from the ethanol-treated group. No changes were observed in the cerebrum and liver. These results further support the idea that [3H]PK 11195 binding may be a useful marker for ethanol consumption. The observed changes in these binding sites may represent a functional adaptive response to the ethanol insult and/or a role in the mediation of the effects of ethanol.

Alcoholism↗