Potential risks of supply shortages for critical metals including rare-earth elements and yttrium (REY) have spurred great interest in commercial mining of deep-sea mineral resources. Deep-sea mud containing over 5,000 ppm total REY content was discovered in the western North Pacific Ocean near Minamitorishima Island, Japan, in 2013. This REY-rich mud has great potential as a rare-earth metal resource because of the enormous amount available and its advantageous mineralogical features. Here, we estimated the resource amount in REY-rich mud with Geographical Information System software and established a mineral processing procedure to greatly enhance its economic value. The resource amount was estimated to be 1.2 Mt of rare-earth oxide for the most promising area (105 km2 × 0–10 mbsf), which accounts for 62, 47, 32, and 56 years of annual global demand for Y, Eu, Tb, and Dy, respectively. Moreover, using a hydrocyclone separator enabled us to recover selectively biogenic calcium phosphate grains, which have high REY content (up to 22,000 ppm) and constitute the coarser domain in the grain-size distribution. The enormous resource amount and the effectiveness of the mineral processing are strong indicators that this new REY resource could be exploited in the near future.

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The Sprint-A satellite with the EUV spectrometer (Extreme Ultraviolet Spectroscope for Exospheric Dynamics: EXCEED) was launched in September 2013 by the Epsilon rocket. Now it is orbiting around the Earth (954.05 km × 1156.87 km orbit; the period is 104 minutes) and one has started a broad and varied observation program. With an effective area of more than 1 cm 2 and well-calibrated sensitivity in space, the EUV spectrometer will produce spectral images (520-1480 Å) of the atmospheres/magnetospheres of several planets (Mercury, Venus, Mars, Jupiter, and Saturn) from the Earth's orbit. At the first day of the observation, EUV emissions from the Io plasma torus (mainly sulfur ions) and aurora (H 2 Lyman and Werner bands) of Jupiter have been identified. Continuous 3-month measurement for Io's plasma torus and aurora is planned to witness the sporadic and sudden brightening events occurring on one or both regions. For Venus, the Fourth Positive (A 1 Π -X 1 Σ + ) system of CO and some yet known emissions of the atmosphere were identified even though the exposure was short (8-min). Long-term exposure from April to June (for approximately 2 months) will visualize the Venusian ionosphere and tail in the EUV spectral range. Saturn and Mars are the next targets.

We describe a low-loss single-mode waveguide in planar light-wave circuit (PLC) glass doped with boron and phosphorus, which is more difficult to write than pure-silica glass. The written waveguide has a rectangular core, a symmetric near-field pattern, and a propagation loss of 0.35 dB/cm. The loss that originates from the mode-field mismatch between the mode-field diameters of the written and the PLC waveguides is less than 0.1 dB/point. In addition, we successfully connected PLC waveguides with a 500-microm-long waveguide written with a laser. The laser-written waveguide can flexibly connect PLC waveguides with a low coupling loss.

In order to investigate the fatigue properties of high‐strength steels in the very long‐life regime up to over 109 cycles, cantilever‐type rotating bending fatigue tests were carried out for two kinds of high‐strength steels, SUJ2 and SNCM439, which were machined by grinding and finished by electropolishing after grinding. And also, the residual stress on the specimen surface of the ground specimen was examined by X‐ray diffractometer in order to investigate effects of the residual stress on the fatigue properties. From the investigations, the S–N curves clearly have a tendency to decrease again in the longer‐life range over 107 cycles for both types of specimen and for both steels. From observations of fracture surfaces, it was found that fatigue crack origins could be grouped into two types: (i) ‘surface crack origin type’ in the shorter‐life regime and (ii) ‘internal crack origin type’ in the longer‐life regime.

15This study aims to investigate the ability of using biopolymer (environmental friendly material) to enhance 16 the mechanical characterizations of collapsible soil. Two types of biopolymers were used in this study 17 (xanthan gum and guar gum) because of their stable behaviour under sever conditions and their availability 18 with reasonable prices. The experimental program focused on three major soil properties, which are; 19 compaction characterizations, collapsible potential and shear parameters, these three properties are 20 essential in any soil improvement process. Different biopolymer concentrations were used in this study and 21 the experimental program was performed at two curing periods (soon after mixing the soil with the 22 biopolymer and after one week curing time). shear parameters were measured for the treated specimens in 23 both soaked and unsoaked conditions, while a collapsible potential test was performed under different 24 mixing conditions (wet mix and dry mix). A numerical model was built to predict the behaviour of the 25 treated collapsible soil after and before inundation. The analysis of results indicated the ability of both 26 xanthan gum and guar gum to be used as soil improvement materials for collapsible soil treatment. The 27collapsible potential has been reduced significantly from 9% to 1% after mixing the soil with 2% 28 biopolymer concentration in the wet case. After one week curing period, the cohesion stress has been 29 increased from 8.5 to 105 kPa by increasing the xanthan gum concentration from zero to 2%, leading to 30 overall improvement in the soil shear strength. Also, it proved that the superiority of guar gum over 31 xanthan gum in improving the shear strength is about 30% more than xanthan gum at the same conditions 32 and reduces the collapsible potential by about 20% more than xanthan gum at the same conditions. 33 34 35

The hydrogen exosphere constitutes the uppermost atmospheric layer of the Earth, and its shape may reflect the last stage of the atmospheric escape process. The distribution of hydrogen in the outer exosphere remains unobserved because outer geocoronal emissions are difficult to observe from within the exosphere. In this study, we used the Lyman Alpha Imaging Camera on board the Proximate Object Close Flyby with Optical Navigation spacecraft, located outside the exosphere, to obtain the first image of the entire geocorona that extends to more than 38 Earth radii. The observed emission intensity distribution can be reproduced using our analytical model that has three parameters: exobase temperature, exobase density, and solar radiation pressure, which implies that hot hydrogen production in the magnetized plasmasphere is not the dominant process shaping the outer hydrogen exosphere. However, the role of the magnetic effect in determining the total escape flux cannot be ruled out.

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