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While land subsidence (LS) caused by groundwater overuse is a significant contributor to inundation in coastal areas, rising sea levels remain the critical factor affecting coastal flooding globally. In this work, we projected potential inundation areas on the midwestern coast of Taiwan in 2100 using a high-resolution numerical model with light detection and ranging (LiDAR)-based digital elevation data. Two simulation approaches, namely, constant spring tide (CST) and dynamic astronomical tide (DAT) approaches, were employed to pair various sea-level rise (SLR) magnitudes from the 6th Assessment Report of IPCC with LS magnitudes reported by the Water Resource Agency of Taiwan. The CST method always projected larger maximum inundation areas (MIAs) than the DAT method. However, the discrepancies in the MIA projections between the CST and DAT methods showed exponential decay as the SLR magnitude increased. Through 1320 scenario simulations, the projected worst-case median MIAs derived using the CST and DAT methods were approximately 1100 and 1000 km2 in the year 2100, respectively, and the synergistic effect of SLR and LS significantly exacerbated the coastal inundation. This study indicates that the DAT approach is more realistic than the CST approach for modelling actual tidal variations and is suitable for assessing coastal inundation due to rising sea levels and subsiding lands worldwide.

Similar material characteristics are observed for the elemental 2D material of group-V antimonene prepared by both molecular beam epitaxy and thermal evaporation on MoSalt;subagt;2alt;/subagt; surfaces. Group-IV germanene and stanene can also be prepared by using the same thermal evaporation technique. With the well stacked hetero-structures, lattice mismatch does not play an important role for van der Waals epitaxy between 2D materials. The observations of the elemental 2D materials instead of their conventional semiconductor structures on MoSalt;subagt;2alt;/subagt; surface demonstrate the preferential 2D structure formation on 2D material surfaces. Compared with the higher growth temperature of germanene, room-temperature growth is observed for stanene. The contact resistance reduction and the integration with the standard metal lift-off procedure on MoSalt;subagt;2alt;/subagt; surfaces has made stanene a promising candidate as the contact metal for 2D devices.

Comparisons on exfoliated graphene nano-sheets and triturated graphite nano-particles for mode-locking the Erbium-doped fiber lasers (EDFLs) are performed. As opposed to the graphite nano-particles obtained by physically triturating the graphite foil, the tri-layer graphene nano-sheets is obtained by electrochemically exfoliating the graphite foil. To precisely control the size dispersion and the layer number of the exfoliated graphene nano-sheet, both the bias of electrochemical exfoliation and the speed of centrifugation are optimized. Under a threshold exfoliation bias of 3 volts and a centrifugation at 1000 rpm, graphene nano-sheets with an average diameter of 100 ± 40 nm can be obtained. The graphene nano-sheets with an area density of 15 #/µm2 are directly imprinted onto the end-face of a single-mode fiber made patchcord connector inside the EDFL cavity. Such electrochemically exfoliated graphene nano-sheets show comparable saturable absorption with standard single-graphene and perform the self-amplitude modulation better than physically triturated graphite nano-particles. The linear transmittance and modulation depth of the inserted graphene nano-sheets are 92.5% and 53%, respectively. Under the operation with a power gain of 21.5 dB, the EDFL can be passively mode-locked to deliver a pulsewidth of 454.5 fs with a spectral linewidth of 5.6 nm. The time-bandwidth product of 0.31 is close to the transform limit. The Kelly sideband frequency spacing of 1.34 THz is used to calculate the chirp coefficient as −0.0015.

We report a method for fabricating ordered spatial arrangements of pre-synthesized CdS nanoparticles in thin block copolymer templates by first selectively dispersing these nanoparticles in one particular block of a diblock copolymer, in bulk, by means of dipole–dipole interactions and then using solvent selectivity to sequester CdS nanoparticles in the block copolymer thin film. A long-range, ordered morphology of CdS nanoclusters can be obtained by using patterned substrates with 400 nm shallow grooves. The incorporated nanoparticles retain the same luminescence characteristics as in the pure state.

The study of controlling high-current proton beam halo-chaos has become a key concerned issue for many important applications. In this paper, time-delayed feedback control method is proposed for beam halo-chaos. Particle in cell simulation results show that the method is very effective and has some advantages for high-current beam experiments and engineering.

To prevent the cracking of GaN thick films grown on a sapphire substrate by hydride vapor phase epitaxy (HVPE), a novel technique without complex processes is developed. By adding a temperature ramping step in the HVPE GaN epitaxy process, more than 300-µm-thick high-quality crack-free GaN thick films on sapphire substrate can be obtained by this technique. After separation by a conventional laser-induced lift-off process, a 1.5 in. 300 µm freestanding GaN wafer with a dislocation density of approximately 1 ×107 cm-2 could be fabricated without any cracks. No additional designed-patterned or stress-reduced structures were applied in these samples to reduce the dislocation density and thermal stress.

There is now ample evidence that fracture surfaces are self-affine. The elastic contact on such surfaces is expected to give rise to a power law dependence of the normal force on the penetration depth, whose exponent α depends on the roughness index of the surface, ζ. This problem is studied experimentally using three different fracture surfaces (bakelite, graphite and plaster) in contact with a flat rubber punch. After an initial regime which can be attributed to the contact of the most salient asperity of the rough surface, the experimental data are consistent with theoretical arguments presented earlier, leading to the relation α = 1 + 1/ζ. Numerical simulations of this problem on artificially generated self-affine surfaces also support this result.

Electron acceleration, in vacuum, mediated by an intense echelon phase-modulated long Gaussian laser pulse, is investigated here. Theoretical and numerical analyses show that this pulse can accelerate an electron to much higher energies than an unmodulated pulse. The staircase-like phase structure of the laser field encourages electron trapping in the favorable wave phase, greatly increasing the effective acceleration distance. Also, the electron motion is now more in the laser propagation direction. The conditions for efficient acceleration are obtained. Since the slower electrons can also be efficiently accelerated to high energies and the accelerated electrons are more axially oriented, the average energy gain by an initially Maxwellian electron bunch can be more than 13 times that obtained without the echelon phase modulation. This is at the expense of somewhat increased spatial and thermal spread, and the accelerated bunch is also more collimated.