This paper describes the possibility of the realization of a multi-function radiation gauge to meet the requirement for more precise and stable control of a blast furnace. A basic concept of the gauge is to measure some quantities with simultaneous use of multi-radiations of neutrons and γ-rays, and to obtain multi-types of information on material flow and gas flow representing the conditions inside the blast furnace. The prototype gauge was assembled and examined which consisted of a radiation source of252Cf (3.7MBq), neutron moderator, lead shield, a bismuth germinate detector, stainless casing and a control unit. Laboratory experiments showed that the gauge could measure the quantities to be essential to estimate the blast furnace conditions. In practice, it clearly distinguished between iron ore and coke layers, and at the same time measured bulk density (1.0 -1.5 g/cm3) of iron contained in iron ore by counting thermal neutron capture γ-rays (6.5 - 8.5 MeV) from iron. It also gave the information on material bulk density (0.5 -2.5 g/cm3) by detecting Compton scattered γ-rays (1.0 -1.5 MeV) from material, i.e. iron ore and coke. The relative accuracies in the measurement of iron bulk density and material bulk density were estimated to be within 1 and 4% in 300 s counting time, respectively. The possibility of the gauge has been proved and the on-line trial will be expected in the near future.
In order to reveal the reactivity of several functional polymers, the following two experiments were carried out : (1) observing the hydrogen-isotope exchange reaction (T-for-H exchange reaction) between one of T-labeled functional polymers and 0.500 mol·1-1aniline dissolved in p-xylene, (2) observing the degree of the T dispersed from the surface area of the polymer under the several conditions. Consequently, the following six matters have been quantitatively obtained. (1) The T-for-H exchange reaction occurred between each T-labeled polymer and aniline, and is more predominant than other chemical reactions within the range of 50 - 90°C. (2) The reactivity of the polymers are strongly affected by their matrix structures. (3) The degree of the T dispersed from the surface area of each T-labeled polymer is hardly affected by humidity. (4) The higher the temperature is, the larger is the degree of the T dispersed from the surface area. (5) At the same temperature, the degree of the T dispersed from the surface area of each polymer is strongly affected by the physical form of the polymer even if the polymer has the same functional group as the others, and the T existing in the surface area of a T-labeled glassy polymer is less dispersed than that of a porous one. (6) The degree of the T dispersed from the surface area of a T-labeled polymer is small when the degree of the polymerization of the polymer is high.
Image quality of scintigrams is influenced by several imaging conditions. But, the relationship between image quality and diagnostic information has been not clearly evaluated. Therefore the diagnostic information was evaluated visually by radiologists using bone scintigrams changing the imaging conditions : total counts, image density, and distance from collimator to patient surface. The diagnostic information was considered the point of whether normal or abnormal scintigrams and in the abnormal scintigrams, the information of abnormal position, the abnormal area and the abnormal radioactive distribution on the bone scintigrams. Analysis of variance for the diagnostic information was performed. We concluded that using our methods the relationship between imaging condition and diagnostic informaton is analyzed quantitatively and the base of imaging technique is evaluated objectively.
An attempt was made to reduce the background counting rate of γ-ray spectrometer commonly used. Additional setting of an inner shield made of oxygen free copper within the ordinary shield was found to work well. Remarkable reduction of spectral lines from radondaughters was observed by introducing N2-gas into the sample chamber to expel Rn together with the daughters existing there. Fluctuation in background also diminished sufficiently and was stabilized. It may be possible to employ the spectrometer of common use, even not to be designed for the low-level counting, for the measurement with high stability of low level radioactivity usig the present simple technique.