Cerium X-ray Spectra without Filtering and their Application to High-contrast Angiography

The cerium-target x-ray tube is useful in order to perform cone-beam K-edge angiography because K-series characteristic x rays from the cerium target are absorbed effectively by iodine-based contrast media. The x-ray generator consists of a main controller, an x-ray tube unit with a high-voltage circuit and an insulation transformer, and a personal computer. The tube is a glass-enclosed diode with a cerium target and a 0.5-mm-thick beryllium window. The maximum tube voltage and current were 65 kV and 0.4 mA, respectively, and the focal-spot sizes were 1.2×0.8 mm. Sharp cerium K-series characteristic x rays were observed without using a filter, and the x-ray intensity was 209μGy/s at 1.0 m from the source with a tube voltage of 60 kV and a current of 0.40 mA. Angiography was performed with a computed radiography system using iodine-based microspheres 15 μm in diameter. In angiography of non-living animals, we observed fine blood vessels of approximately 100 μm with high contrasts

Positive Electrode Performance of All-Solid-State Battery with Sulfide Solid Electrolyte Exposed to Low-Moisture Air

All-solid-state batteries (ASSBs) using sulfide solid electrolytes (SEs) are attractive candidates as next-generation energy devices having longer lifetimes than liquid-type lithium-ion batteries (LIBs) using organic solvents. Sulfide SEs are known that to suffer a decrease in their ionic conductivity and generate toxic hydrogen sulfide when exposed to moisture even in an environment such as in a dry room. However, the influence of the exposure to moisture on the ASSB cell performance has not been fully elucidated so far. Aiming at filling this gap of knowledge, this paper describes the investigation of the influence of moisture on the durability of an ASSB positive electrode with sulfide SE unexposed or exposed to dry-room-simulated air with dew point of −20 °C in this study. After the cell durability evaluation, time-of-flight secondary-ion mass spectrometry (ToF-SIMS) measurements were performed on positive electrode, and a characteristic degradation mode was observed in the cell using the exposed SE

AC Impedance Analysis of the Degeneration and Recovery of Argyrodite Sulfide-Based Solid Electrolytes under Dry-Room-Simulated Condition

Toward the development of all-solid-state batteries with enhanced performance, this study describes the investigation of the degeneration mechanism under low-humid conditions of an argyrodite-type sulfide-based solid electrolyte. The degeneration of the electrolyte with moisture occurs even under the condition of super-low humidity in a dry room with a dew point (dp) as low as −50 °Cdp. Formation of hydrogen sulfide is detected when the electrolyte is exposed to dry air with −20 °Cdp. The results of impedance measurements suggest that the grain surface of the electrolyte is degenerated with moisture, resulting in a decrease in the lithium-ion conductivity at the grain boundary. The degenerated electrolyte surface can be partially recovered by heating at 170 °C in vacuo, although a small degeneration in bulk may occur in the heating process