方鉛鉱に関する1, 2の基礎的性質について
示差熱分析および半導体的特性
1959 年 75 巻 856 号 p. 917-922
詳細
1959 年 75 巻 856 号 p. 917-922
The authors have investigated on the physical and chemical properties of galena produced from typical lead-zinc mines in Japan. Differential thermal analyses, thermal balance measurements, x-ray study and measurement of electrical properties were carried out. It was found that these properties are influenced by minor impurities. The main results obtained are as follows:
(1) Differential thermal analysis curves showed two exothermic reaction at 770°C and 840°C, and a slight endothermic reaction at 850°-855°C.
(2) According to the thermal balance measurement, weight began to increase at 310°C and changed to decrease at 750°C, a little inflection was observed on the decreasing curves at 850°-900°C.
(3) Besides lead sulfide, lead sulfate, lead oxide and metallic lead were determined in the heated samples by x-ray spectrometer.
(4) Because of minor impurities, exothermic reaction caused by oxidation of disordered samples began at lower temperature than that of ideal sample.
(5) Semiconductivity of galena depends on its minor impurities, especially silver and bismuth.
