Rapid shortening in convergent mountain belts is often accommodated by slip on faults at multiple levels in upper crust, but no geodetic observation of slip at multiple levels within hours of a moderate earthquake has been shown before. Here we show clear evidence of fault slip within a shallower thrust at 5–10 km depth in SW Taiwan triggered by the 2016 Mw 6.4 MeiNong earthquake at 15–20 km depth. We constrain the primary coseismic fault slip with kinematic modeling of seismic and geodetic measurements and constrain the triggered slip and fault geometry using synthetic aperture radar interferometry. The shallower thrust coincides with a proposed duplex located in a region of high fluid pressure and high interseismic uplift rate, and may be sensitive to stress perturbations. Our results imply that under tectonic conditions such as high‐background stress level and high fluid pressure, a moderate lower crustal earthquake can trigger faults at shallower depth.

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Simulations incorporating the spatial distributions of the energy band and temperature have been used to study AlGaAs/GaAs heterojunction bipolar transistor characteristics. The coupled heat transfer and conventional device carrier transport equations were solved numerically in two dimensions using both the voltage and current boundary conditions applied on the base contact. An equivalent thermal resistance model was used to establish the temperature boundary condition between the electrically active device and the relatively large thermally active semi-insulating substrate. The negative differential resistance and the reduction of the base-emitter voltage for a constant base current in the active region are caused by the thermal effects. The differential current gain and cutoff frequency are decreased when the transistor is operated at high power levels. The temperature distribution of the transistor operated in the active region shows a maximum temperature occurring at the collector region right beneath the emitter mesa. When the transistor operated in the saturation region, the emitter contact region may be at a slightly lower temperature than the heat sink temperature. This thermoelectric cooling effect reults from the utilization of the thermodynamically compatible current and energy flow formulations in which the energy band discontinuities are part of the thermoelectric power. NOMENCLATURE Net doping density. Thickness of substrate. Conduction band edge. Valence band edge. Energy bandgap. Quasi-Fermi energy for electrons. Quasi-Fermi energy for holes. Fermi-Dirac integral of the j th order given by X J dr r (j + 1) o 1 + exp (X-y) ' Base current density (A/m). Collector current density (A/m). Energy flow (W/m2).

Photopolymerization processes are often used in industrial applications because of their solvent-free formulations and various advantages over conventional thermal processes. Fluorinated monomers and oligomers yield coatings of great interest because of the peculiar characteristics of fluorine atoms: these coatings show hydrophobicity, chemical stability, weathering resistance, etc. Novel UV-curable fluorinated epoxy acrylate oligomers were synthesized from 1H,1H-perfluorohexan-1-ol, 1,6-hexamethylene diisocyanate (HDI) and epoxy acrylate (EA). The HDI plays the role of a spacer group in the side chain between the EA backbone chain and the fluorinated segment. This new spacer containing a urethane moiety with long alkyl groups can exhibit a self-organization effect through the formation of strong hydrogen bonding. This resulted in a stiffening of the whole HDI urethane-perfluoalkyl chain to form nanostructure surface segregation. The designed fluorinated EA with fluoroalkyl (C 5 F 11 ) units in the side chain exhibited a contact angle of about 151 • , which is in the superhydrophobic range.

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We report the largest peak-to-valley current (PVC) ratios to date from AlGaAs/GaAs double barrier (either alloy barrier or superlattice barrier) diodes. PVC ratios as high as 3.6 and 21.7 were obtained from an AlAs/GaAs superlattice barrier structure at 300 and 77 K, respectively. In an alloy barrier structure with x=0.42 (x=0.3), PVC ratios of 3.9 (2.2) and 14.3 (7.0) were observed at 300 and 77 K, respectively. We attribute these excellent results to a ‘‘two-step’’ spacer layer incorporated in the devices studied which facilitated the growth of high material quality.