Total weight and mean concentration of atmospheric suspended dust in Keihin industrial and suburban area were estimated from the distribution function of the atmospheric suspended dust concentration over this area.
From the measuring results of the atmospheric suspended dust concentration at five observation sites on the ground, and at an altitude of 100-1, 000 meters by helicopter, the distribution of the atmospheric dust concentration over this area was represented by w_xh=0.05C/x^m exp (-2.237h), where w_xh is monthly mean value of the atmospheric suspended dust concentration over this area (mg/m³), x is the distance from the center of this industrial area (km), h is the height from the ground (km), and C and m are constants.
Therefore, total weight w_TRH (ton) of suspended dust in cylindrical atmosphere whose center is that of industrial area, radius is R (km), and height is H (km), was calculated by
w_TRH=πC/10∫^R_O∫^H_Xx^1-mexp (-2.237h) dx dh, and mean dust concentration C_RH (mg/m³) in this space was expressed by C_RH=WTRH/πR²
Monthly mean values of w_TRH in cylindrical atmosphere whose radius is 20km, height is 1 km was 67-139ton and was 47-91 ton in the atmosphere of radius 15 km.
And mean concentration in these space were respectively 0.053-0.111mg/m³, and 0.066-0.129 mg/m³.

抄録全体を表示

Since A.A.S has been developed by walsh, it is used on determination of metals in several materials. As the application of this instrument, the elements of iron, copper, lead, and zinc in dustfall (ash) are determined also. For this purpose, extraction or addition of organic solvent or dilution is used in such experiment. It is known that analysis sensitivity is increased by the use of organic solvent. Among these methods, reasonable results wese achieved in dilution method in this paper. Dustfall (ash) was treated with each three kind of acid (nitric acid, hydrochloric acid and perchloric acid) and their mixtures (a mixture of nitric acid and perchloric acid, a mixture of nitric acid and hydrochloric acid, and a mixture of hydrochloric acid and perchloric acid).
From the results treatment with hydrochloric acid might be better than that of another one. In the present step, the experiment of alkali fusion is examined in futher studies and its results will be reported later. In the experiment two detection methods were adopted: they were calibration curve method and standard addition method.
It is known that the calibration method is easier to operate, but the addition method reasonable to protect the interference. In this paper, metal absorbance mesured by addition method was not always high.

抄録全体を表示

The experimental device for the removal of SO₂ in flue gases is a wet type cylindrical electric precipitator with liquid irrigated glass wall (positive electrode) and a wire at its center producing a corona discharge between them (spacing 1.35cm). The gas was derived from the device analyzed by “Analytical methods for determining total sulphur oxides in flue gases-JIS KO 103 (1963)”
The results of these experiments are summarized as follows.
(1) The characteristics of the SO₂-removal efficiency for the applied voltage are hardly different between the positive and negative corona discharges at moderate applied voltage.
(2) The SO₂-removal efficiency increases with increasing the corona voltage but it is saturated at some high applied voltage. It is yielded more than 95% at the applied voltage above 9 kV, when the SO₂ concentration is less than 0.6%.
(3) The SO₂-removal efficiency increases in proportion to the reaction time of gas.
(4) When the irrigated liquid is aqueous Na₂CO₃ of 5% or aqueous H₂SO₄ of 10% instead of water, the SO₂-removal efficiency becomes nealy 100% and 34% at 7kV, respectively.

抄録全体を表示

The major purpose of this work is in the development of an appropriate mathematical model for an urban air-quality prediction.
A main problem of the model building is to express the diffusion process of pollutant in a simple and reasonable form.
A new model from phenomenological standpoint is presented combining convectional steady state transport equations with a first order differential equation with respect to time. The model includes some parameters, which are much affected by meteorological factors, and are analysed by using actual data on meteorological conditions, pollutant concentration and source intensity. Model parameters were well correlated with meteorological variables but those are unreliable and uncertain at present, the notion of adaptive control is introduced to update the model parameters. With this notion the model will prove suitable for the urban air-quality prediction.

抄録全体を表示

In the first report, the simple mathematical algorithm for computing pollutant concentration was presented for urban area, in which the relations between specific meteorological conditions and parameters were specialized.
This report is related to the methodology of estimation of pollution level and to its results. The prediction of concentration is done on the assumption that wind speed and wind direction can be accurately forecasted.
The procedure of “adaptive treatment” is applied to parameter estimation which is compared with “deterministic treatment”.

抄録全体を表示