This paper presents techniques for determining the mean trajectory of plume emitted from a stack. Equations presented are not intended to provide a means for predicting day-to-day variations in plume trajectory for a given stack.
This investigation has been analyzed on the basis of the theory that there is a non-linear relation between plume rise and distance downwind on the Log-Log graph, not on the traditional linear relation “2/3 Power-Law.”
The equations for predicting plume trajectory are developed statistically and give good agreement with many field data which were observed not only in Japan, but in U.S.A. and Europe.

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This paper deals with techniques for estimating maximum rise of the bent-over plume. Information on plume rise is important in determining the concentrations of pollutant on the ground. Practical use of plume rise values may be made in connection with stack design, the use of urban air pollution mod ls, and in evaluating the hazards to a population complex.
This investigation is made on the objective assumption that the plume is levelled off when its vertical velocity is below 0.1 m/sec so that it can yield levelled-off point (x_max) and maximum plume rise (ΔH_max). The empirical formulas for estimating maximum plume rise are derived by multiple regression analysis and give good agreement with many field data.

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Mass-size distributions of atmospheric aerosols in Kitakyushu city were measured by use of Andersen sampler, and their trends in past three years (1974-1976) were investigated. The results showed that the distributions of aerosols are divided near 1-2μm into two groups, coarse and fine particles, regardless of sampling stations, seasons or years. Since differences in total aerosol concentration among sampling stations are due mainly to particles larger than 1μm (coarse particles), this particles are considered to begenerated artificially. For seasonal variations, the concentration of the coarse particles at the reference station also tends to increase in spring.
Therefore, different meteorological conditions and natural phenomena in addition to artificial sources may take part in an increase of the coarse particles. The division of the aerosols into two groups implies that the coarse and fine particles differ in their sources, formation mechanisms and removal processes.

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本論述は,一般に使用されているガンリンエンジン自動車からの多環芳香族炭化水素(PAH)排出の主要因について調べたものである。
ガソリンエンジン車からのPAH排出には,ガソリン由来のものと,エンジンオイル由来のものがある。前者としては,ガソリン中のPAH,ガソリンからの生成PAHの寄与が考えられ,後者としては,オイル中に蓄積したPAH,消費オイルからの生成PAHの寄与が考えられた。
ガソリン中のPAHは,その1-2%程度が燃焼過程を生き残り,排気ガスと共に排出された。又,ガソリンからのPAH生成量は,1l当りおよそ次の様に推定された。BaP1μg,BaA5μg,クリセン5μg,ピレン24μg。エンジンオイル中へのPAHの蓄積は,市中走行条件では,大部分がガソリン中のPAHに起因し,その蓄積量はオイル使用距離に比例して増加した。この蓄積PAHは消費オイルと共に排出された。そして消費オイルの増加は,そのオイルからの生成PAHの増加をも伴って,PAEの高い排出を引き起した。
通常使用されているガソリン車について,平均的にみると,BaP,BaA,クリセンの排出の60%以上は,消費オイルからの生成によった。以下,他の要因からの寄与は,ガソリン中のもの,ガソリンからの生成,オイル中のもの,の順に減少した。特に,ピレンの排出に関しては,ガソリン中の濃度が非常に高い為,ガソリン中のピレンからの寄与が4696を占め,主要因であった。以下,消費オイルからの生成,オイル中のピレン,ガソリンからの生成の順に排出への寄与は減少した。

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下水道施設, し尿処理場などから発生する不快なガスが大気を汚染し, 悪臭公害を起こしている。その悪臭成分中の硫化水素を次亜塩素酸塩 (過酸化水素) で処理する際, 共存するアンモニア, トリメチルアミンはあらかじめ塩酸水溶液で除去してから硫化水素の酸化を行ったが, この方法では炭酸ガスが多量共存すると硫化物の処理工程において, 炭酸塩によるスケールトラブルを起こすおそれがある。
その対策と悪臭成分中のアンモニア, トリメチルアミンを次亜塩素酸塩で酸化し, 悪臭を防除するため, 充填塔を用いて, アンモニア (2～10ppm), トリメチルアミン (1～5ppm) を次亜塩素酸ナトリウム溶液に吸収・酸化させ, 総括容量係数 (KGa) を検討した結果, 常温における最適処理条件は, ガス空塔速度は1.7m/s, 液ガス比は2, 吸収液のpH値は7前後, 次亜塩素酸ナトリウムの濃度は1.5×10^-3mol/lであることがわかった。
この条件で, 実装置により排ガス中のアンモニア, トリメチルアミンは硫化物の処理工程において炭酸塩のスケールトラブルもなくほぼ完全に処理できた。

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Aldehydes can be determined as their imidazolidine derivatives formed by reaction of aldehydes with N, N'-diphenylethylenediamine (DPED). This investigation was developed for the gas chromatographic determination of aldehydes in the atmosphere as their imidazolidine derivatives by sampling into absorption bottle.
For imidazolidine derivatives derived from formaldehyde, acetaldehyde, propionaldehyde and butyraldehyde, the stability in absorption solution and extraction solvent, the recovery, and the trapping efficiency of these aldehydes were examined. Phosphoric acid solution of DPED as absorption solutionand trichlormethane as extraction solvent were used. Good results were obtained for formaldehyde and acetaldehyde.
The merit of the proposed method is as follows: a large volume of air is not required, because the detectable sensibility for formaldehyde and acetaldehyde was good, both about 0.2 ng, and the effect of blank of absorption solution was not found.
The lower limits of determination (sampling air: 30 1, condensed volume of extractant: 1 ml) were 0.5 ppb for formaldehyde and 0.3 ppb for acetaldehyde.
Formaldehyde concentrations in the air of road tunnel were determined by the present method, showing a good agreement with the results obtained by the 4-amino-3-hydrazino-5-mercapto-1, 2, 4-triazole method.
The gas chromatographic method presented above can especially be used for the determination of formaldehyde in the atmosphere.

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As absorbing reagents serving as color developing reagent, N, N'-diethyl-p-phenylenediamine (DPD), 3, 3'-dimethylnaphthidine (DMN) and 2, 2'-adino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were examined. The most suitable pH and composition in each solution is as follows: DPD: PH 6.3, 0.2 mg/ml, DMN: 3, 6μg/ml, ABTS: 2.5, 0.1 mg/ml. The collecting vessel used in DPD and DMN method was not a sinteredglass bubbler but a midget impinger. In ABTS method, sample air must be drawn with a sintered glass bubbler (No.1, pore size: 0.1-0.12 mm). Maximum drawing rate to obtain collection efficiency near 100% with 10 nal of the solution (depth: 22 mm) and observed chlorine recoveries from standard gas flow were as follows: DPD: 1.5 liter/min, 96%; DMN: 0.8, 97; ABTS: 1.5, 100. ABTS method had large colorstability and little interference of SO₂, DMN method had low blank value and little interference of NO₂ and O₃. These two methods were better than usual o-tolidine method. The Cl₂ concentration which may be determined with sample size of 1 liter and coefficient of variance in the determination were as follows: DMN: 0.22-2 ppm, 3.2%; ABTS: 0.13-3, 2.8.

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Five plants which are very sensitive to photochemical oxidants were exposed to various concentrations of ozone or PAN (peroxyacetyl nitrate) for several different periods of time; spinach, radish, taro, peanut, and petunia for ozone and petunia for PAN were tested in a controlled atmospheric chamber.
As a result, the injury degrees of the five plants for ozone or PAN were logarithmically dependent upon both concentration and exposure duration. In this view, the interrelationships between concentration and exposure duration and plant injury could be analyzed using the mathematical model which was derived from our previous ozone exposure experiment on morning glory: S=m ln C+ n ln t+K, where S is the plant injury degree, C is ozone or PAN concentration in ppm, t is the exposure duration in hours, and m, n, and K are constants. To determine the constants for these plants, multiple linear regression calculations were made by using the mean values of injury degrees. Because the values of m and n for each plant were different, as obtained by the calcul ations, the degree of injury was not in a simple linear relation to ozone or PAN dosage (C×t). Therefore, when the conventional dosage (C×t) is substituted by the powered dosage of Cm/n×t, the injury degree can be expressed as a function of one variable which combines concentration and duration. The values of min for the five plants ranged from 1.61 to 2.43 for ozone, while the value for petunia was 1.33 for PAN.
Spinach was the most sensitive plant for ozone of the five plants and morning glory; the injury threshold concentrations for ozone were obtained as 0.128, 0.065, and 0.035 ppm for 1, 3, and 8 hours, respectively. For petunia the threshold values for PAN were 0.032, 0.014, and 0.007 ppm for 1, 3, and 8 hours, respectively.

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Measurements of total aluminum and water-soluble coarse (>2μm) sodium concentrations in the aerosols of Nagoya urban area were made, from September 1976 to April 1979 and the contributions of soil and sea salt to aerosols in urban air was described. The average background concentration of soil particles in the three seasons except spring was about 15 μg/m³. In the spring, yellow sand dusts called Kasa were transported from North China to Japan, so that the concentration increased to about 30 μg/m³. On the other hand, the average background concentration of sea salt particles was about 2-3 μg/m³. It was estimated that the environmental impact from primary natural sources was about 25% of the total aerosols in the Nagoya urban area, and especially in spring was about 40%.

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