Electrodeposition of Cobalt from LiCl-Based Highly Concentrated Aqueous Solution: Crystal Phase and Hydrogen Content

The relationship between the crystal phase and absorbed hydrogen in cobalt electrodeposited from a LiCl-based highly concentrated (HC) aqueous solution was investigated using X-ray diffraction and thermal desorption spectroscopy. We expected that the use of an HC solution would enable the electrodeposition of cobalt without hydrogen evolution and the concomitant hydrogen absorption. The current efficiency of cobalt deposition was more than 99% at potentials above −0.8 V vs. Ag/AgCl, indicating that hydrogen evolution is really suppressed, but the electrodeposited cobalt accompanied the fcc phase irrespective of the deposition temperature. Moreover, electrodeposited cobalt contained a large amount of hydrogen despite the high current efficiency. The hydrogen content of cobalt obtained at 100°C was approximately 10% of that obtained at room temperature; however, the fcc phase was still co-deposited, suggesting that factors other than hydrogen could be responsible for fcc-Co formation. The reason for hydrogen inclusion from the HC solution is discussed in terms of the hydrogen reduction mechanism

Development of high-speed and high-efficiency downlink transmitter with GaN-HEMT amplifier and pre-distortion technique for nano/small satellite

A high-speed downlink telecommunication system is required to meet various applications for small satellites such as earth observation. The purpose of this research is to develop a high-data-rate (typically over 300Mbps) communication system. Generally, the operation at nonlinear region provides high efficiency for a RF power amplifier. However the amplitude-phase modulated signal, which is an efficient scheme in term of frequency band, requires high linearity. In order to amplify amplitude-phase modulated signal for high data rate, a 2W X Band GaN-HEMT power amplifier and digital pre-distortion technique were developed. In this paper measurements and simulations of the system are presented

Epigallocatechin gallate suppresses peritoneal fibrosis in mice.

Long-term peritoneal dialysis (PD) leads to histological changes in the peritoneal membrane. Angiogenesis and inflammation caused by glucose degradation products (GDPs) play crucial roles in peritoneal fibrosis. One such GDP is methylglyoxal (MGO), which enhances the formation of advanced glycation end products (AGEs). AGEs bind to their receptor (RAGE) and activate nuclear factor-κB (NF-κB), which is a key regulator of angiogenesis and inflammation. Recent studies have indicated that (-)-epigallocatechin gallate (EGCG), a tea polyphenol, inhibits angiogenesis and inflammation. Here, we examined whether EGCG suppresses peritoneal fibrosis in mice. Based on preliminary examination, 2mL of 40mM MGO or PD fluid was injected intraperitoneally and EGCG (50mg/kg) or saline was injected subcutaneously for 3weeks. In comparison to PD fluid+saline-treated mice, the peritoneal tissues of MGO+saline-treated mice showed marked thickening of the submesothelial compact zone. In the submesothelial compact zone of the MGO+saline-treated mice, CD31-positive vessels and vascular endothelial growth factor-positive cells were significantly increased, as were inflammation, F4/80-positive macrophages, and monocyte chemotactic protein-1. Moreover, 8-hydroxydeoxyguanosine, a marker of reactive oxygen species, and NF-κB, determined by Southwestern histochemistry, in the submesothelial compact zone were also increased in MGO+saline-treated mice. These changes were attenuated in MGO+EGCG-treated mice. We demonstrated that EGCG treatment suppresses peritoneal fibrosis via inhibition of NF-κB. Furthermore, EGCG inhibits reactive oxygen species production. The results of this study indicate that EGCG is a potentially novel candidate for the treatment of peritoneal fibrosis

Broadband Multi-wavelength Properties of M87 during the 2017 Event Horizon Telescope Campaign

Abstract: In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 109 M ⊙. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded

300 Mbps Downlink Communications from 50kg Class Small Satellites

Recently small satellites start playing important roles in earth observation missions. It, however, is true that small satellites have drawbacks of sensor resolutions and down link data rate. As a solution to the latter drawback, we have developed novel communications system for 320Mbps down link with 16QAM for small satellites with 50kg class. We developed a new GaN HEMT X-band amplifier with high efficiency and small distortion, digital filter and pre-distortion processing with relatively low clock frequency in FPGAs, and small X-band on-board antennas. As ground segments, we are developing a compact S/X dual band ground antenna station and a high performance demodulator with turbo equalizer/decoder based on CCSDS high rate telemetry standard. These technologies will be demonstrated in 2014 by Japanese Hodoyoshi-4 satellite with 50 kg mass

Electrodeposition of Cobalt from LiCl-Based Highly Concentrated Aqueous Solution: Crystal Phase and Hydrogen Content

The relationship between the crystal phase and absorbed hydrogen in cobalt electrodeposited from a LiCl-based highly concentrated (HC) aqueous solution was investigated using X-ray diffraction and thermal desorption spectroscopy. We expected that the use of an HC solution would enable the electrodeposition of cobalt without hydrogen evolution and the concomitant hydrogen absorption. The current efficiency of cobalt deposition was more than 99% at potentials above −0.8 V vs. Ag/AgCl, indicating that hydrogen evolution is really suppressed, but the electrodeposited cobalt accompanied the fcc phase irrespective of the deposition temperature. Moreover, electrodeposited cobalt contained a large amount of hydrogen despite the high current efficiency. The hydrogen content of cobalt obtained at 100°C was approximately 10% of that obtained at room temperature; however, the fcc phase was still co-deposited, suggesting that factors other than hydrogen could be responsible for fcc-Co formation. The reason for hydrogen inclusion from the HC solution is discussed in terms of the hydrogen reduction mechanism

High Bit-rate Communication in X Band for Small Earth Observation Satellites - Result of 505 Mbps Demonstration and Plan for 2 Gbps Link

A compact 64APSK X band transmitter for small satellites with maximum 538 Mbps, mass of 1.3 kg, and power consumption of 22 W has been developed. This transmitter was onboard on Hodoyoshi 4 satellite with 66 kg mass and 505 Mbps downlink was demonstrated. The main characteristics of this downlink system are as follows: i) GaN HEMT X band power amplifier with a high power efficiency and a small nonlinear distortion, ii) application of an error correction code (SCCC, CCSDS 131.2-B-1) with high coding gain. We present a plan of 2-3 Gbps downlink system in X band