A series of trichlorogermanate(II) salts (AGeCl3, A = Rb, Cs, CH3N H3, and (CH3)4N) have been synthesized and characterized by 35Cl NQR , 35Cl NMR , AC conductivity, DTA, and X-ray diffraction techniques. In the temperature range studied two, two, five, and four phases were confirmed for the Rb, Cs, CH3NH3, and (CH3)4N salts, respectively. From the 35Cl NQR and structural data, isolated pyramidal GeCl3 anions were recognized in the low temperature phases. With increasing temperature the relaxation times of the 35Cl NQR decreased exponentially and the signals disappeared far below the melting point. This suggests that the reorientation of the anion about the pseudo three-fold axis is excited. With further increase in temperature, the ionic conductivity of CH3NH3GeCl3 and (CH3)4NGeCl3 increased drastically at the phase transitions to their cubic perovskite phases (CH3NH3GeCl3:σ= 10-1 Sm-1 at 400 K, (CH3)4NGeCl3: σ = 5 x 10-2 Sm-1 at 420 K). The mobile ion was confirmed to be the chloride ion by means of 35Cl NMR and X-ray diffraction.

A high-enrichment method by liquid-liquid extraction using liquid surfactant membranes was developed for the determination of cobalt at pg cm-3 levels by graphite furnace atomic absorption spectrometry (GF-AAS) . Two cubic centimeters of w/o [water in oil, in this case dilute hydrochloric acid in kerosene (l:l) containing 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (PC-88A)] emulsion droplets coated with sorbitan monooleate are dispersed in a resulting volume of 1000 cm3 of an aqueous sample solution (pH 4.7 -5.8) containing less than 1 mg of cobalt(II) . The analyte is extracted into the organic phase to form a complex with PC-88A and successively back-extracted into the inner acidic aqueous phase. After the w/ o emulsion phase is separated from the outer aqueous phase , the emulsions are demulsified into the organic and inner aqueous phases. The cobalt content is then determined by GF-AAS with an injection volume of 10 mm3 of the inner aqueous phase. By this procedure, a concentration factor of 550 was achieved for cobalt(II). As a result, the detection limit of cobalt was 10 pg cm-3 , and the calibration graph was linear up to 1 mg cm-3 of cobalt(II). The relative standard deviation for ten replicate measurements of 50 pg cm-3 cobalt(II) was 7.1 %. The results of an analysis of simulated nuclear reactor coolant water are given.

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We observed a stellar occultation by (3200) Phaethon, which occurred in western Japan on 2021 October 3 (UTC). This observation was requested by the DESTINY+ mission team, which plans to conduct a flyby of asteroid Phaethon in 2028. Overall, this research effort contributes towards a large-scale observation campaign with a total of 72 observers observing from western Japan to southern Korea. 36 stations were established, and stellar occultation by the asteroid Phaethon was detected in 18 of them. This is the first time that this many multiple chord observations have been made for such a small asteroid (it has a diameter of 5–6 km). Observational reductions show that the apparent cross-section of Phaethon at the time of the occultation could be approximated using an ellipse with a major diameter of 6.12 ± 0.07 km and a minor diameter of 4.14 ± 0.07 km, and a position angle of 117.°4 ± 1.°5. As can be seen from the small error bars of the fitted ellipse, we have succeeded in estimating the shape and size of the asteroid with an extremely high degree of accuracy. Our observation results, together with other observations, will be used to create a 3D model of Phaethon and to improve its orbit. The instruments that we used for this observation are commonly used by many amateur astronomers in Japan for occultation observations and are not difficult to obtain. This paper describes the method and results of our observations using a CMOS camera and a GPS module, so that many people can participate in occultation observations in the future.

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