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The Great 2011 Thailand flood is one of the most catastrophic flood disasters recorded worldwide in modern history, which covered about 100,000 km2 of the country and resulted in 813 casualties and incurring US$ 46 billion in economic losses. In this paper, we re-evaluate the flood event to identify the root source of the catastrophe. By analyzing hydrological data from gauge stations along the Chao Phraya River (CPR) and remote sensing data, we decoupled the volumetric contributions of river overflow and local rainfall to the lowland reach of the basin and found that the latter contributed most to the flooding. More specifically, out of the total of 77.6 km3 of floodwaters estimated, 73.7% was from precipitation, while only 26.3% was from river discharges. This finding differs from the official reports or previous studies, which attributed the main cause of the river overbank flow. Therefore, it is also inferred that the upstream dam operations would have been only marginally helpful in mitigating the flood since rainfall made up most of the floodwaters in the downstream reach of the river. Our finding offers a new perspective that the local rainfall could be a significant source of the floodwater, rather than river overflow in the lower reaches of a large monsoonal river system in Southeast Asia. Thus, this paper contributes to the understanding of complex flood processes in large river basins and provides fresh insights for efficient flood control and stormwater management.

Selective control of wetting is highly demanded for a broad window of applications. To selectively control wetting a surface should be locally modified by structuring surfaces or modulating surface chemistry. However, the local modifications are still challenging due to their complex and expensive processes. In this report we demonstrate the development of a facile approach for selective control of wetting on various substrates. Taking superhydrophobic polypropylene particles and hydrophilic silica nanoparticles, we here show that the locally controlled wetting can be achieved by coating the particles on a wide range of substrates including metal and paper and be applied to microfluidic channels. Furthermore, we represent that the coating method can be applied to any surfaces regardless of compositions and geometries.

We investigate the problem of estimating magma chamber geometry using InSAR observations of Sierra Negra Volcano, Galapagos. Ascending and descending interferograms are combined to determine vertical and one horizontal component of displacement. The ratio of maximum horizontal to vertical displacement suggests a sill-like source. Spherical or stock-like bodies are inconsistent with the data. We estimate the geometry of the sill assuming a horizontal, uniformly pressurized crack with unknown periphery and depth. The sill is discretized into small elements that are either open and are subjected to the pressure boundary condition or remain closed. We find the best-fitting sill to be located beneath Sierra Negra's inner caldera at a depth of about 2 km. Using boundary element calculations we show that any magma chamber with a flat top coincident with the sill model fits the data equally well. The data are insensitive to the sides and bottom of the magma chamber.

In this work, we demonstrate the synthesis of various types of boron nanowire junctions in a self-assembled manner by simple closed-tube thermal vapor transfer method. The Y-type boron nano-junctions and lateral boron-silicon alloy nano-junctions were grown on Si substrates, based on the oxide assisted VLS growth mode at a relatively low processing temperature regime and the VLS growth mode at the high processing temperature regime, respectively.