Reduced pressure tests were conducted in an pressure chamber. The purpose of these tests was to determine the characteristic behavior of the chemiluminescent ozone analyzer, UV absorption ozone analyzer and chemiluminescent nitrogen oxides analyzer to changing altitude, as in an unpressurized aircraft.
The instruments were placed in the chamber and calibrated at 1 atm. The chamber was then sealed and partially evacuated. Tests were run over the range of pressures corresponding to ground level to an altitude of approximately 2000 meters above sea level.
The results obtained were as follows:
1) The read out values of the chemiluminescent and UV absorption ozone analyzers decreased by approximately 22% at 0.78 atm (≅2000 meters above sea level), and the decreasing rate of the read out values was nearly equal to that of ambient pressure.
2) The read out values of the chemiluminescent NO, NO_x analyzers decreased by 0-12% at 0.78 atm. The decreasing rate of the read out values was smaller than that of ambient pressure, and differed in each analyzer.
3) The influence of ambient pressure on ozone analyzers is principally due to the change of the mass flow rate of the sample air (in the case of chemiluminescent method), or due to the change of the mass concentration of ozone in absorption cell (in the case of UV absorption method).
4) The influence of ambient pressure on chemiluminescent NO, NO_x analyzers is due to the change of the mass flow rate of the sample air and the change of response per unit mass flow rate.

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Particulate nitrite (NO₂^-) was generated by introducing purified air (12.5l/min) in 1.38-13.8 mg/ml NaNO₂ aqueous solution contained in a glass spherical nebulizer, to investigate the sampling method and the chemical behavior of the NO₂^-in the air. Saltzman method was also investigated for sampling of particulate NO₂^-, comparing with filter method.
NO₂^- could be generated at any concentration and the concentration may be maintained constant for long period of time (>4 hr), and NO₂^- impregnated filter was able to be prepared dynamically.
Filter method, as well as Saltzman method, is applicable to the NO₂^-sampling at high concentration (0.1-1 mmol/m³), but in both methods, it is necessary to remove interfering substances (O₃-H₂O and NO_x), for the sampling at atmospheric concentration.

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Parsley (Petroselinum crispurn) was sown in March, grown under protection from sunlight in an urban, and a rural area, and sampled in July and November. The leaf surface lipids were extracted with n-hexane, and analyzed for hydrocarbons by gas chromatography and gas chromatography-mass spectrometry after purification with column chromatography and thin-layer chromatography. Normal C_18-34 alkanes were 80.4-94.8% in the total hydrocarbons (THC). Main constituents of the alkanes were n-nonacosane (n-C₂₉), n-heptacosane (n-C₂₇), and n-pentacosane (n-C₂₅). Branched alkanes, such as 2-methylheptacosane and 2-methylnonacosane, were found as minor constituents. 1-Alkenes with C_20-32 were 1.5-2.9% of the THC, and their major components were 1-octacosene (C₂₈=1) and 1-hexacosene (C₂₆=1). The amounts of the THC in the urban samples were twice levels those in the rural ones in both July and November. The composition patterns of the hydrocarbons were similar in both areas in July. However, in the November samples, the major components of the alkanes (n-C29, n-C27 and n-C25) and the alkenes (C₂₈=1 and C₂₆=1) decreased in the urban, whereas increased considerably in the rural. Analytical data of a comparative parsley from an agricultural area were similar to those of the rural ones. These results suggest strongly that a significant increase of the leaf surface THC of parsley will be observed under conditions of air pollution, and that the major hydrocarbon components tend to decrease with growth-time under heavily polluted air conditions.

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The Tokyo Metropolitan Government (TMG) model is one of the dispersion model for automobile emission, which is based on the Gaussian plume model. The original TMG model has a tendency of overestimation under parallel wind direction and low wind speed condition. The purpose of this study is to improve the original TMG model. The refinements of this model are inclusion of the traffic-induced turbulence and the shear flow correction. Calculated concentrations by the original and modified TMG models are compared with the air tracer diffusion experimental data. Good agreement is obtained between the measured and calculated concentration-downwind distance profile. The correlation coefficient for measured and calculated by modified TMG model is 0.87.

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Methanol is converted to formaldehyde by oxidation with potassium permanganate. The excess of potassium permanganate is reduced with sodium sulfite to be colorless. The formaldehyde determined spectrophotometrically with pararosaniline is an estimation of the methanol.
It was found out that an addition of propionaldehyde in the methanol oxidizing agents increased in sensitivity for the spectrophotometric determination of methanol. Sodium tetrachloromercurate II (TCM) solution was used as the stabilization reagent of sodium sulfite. But the TCM solution containing mercury compound is high poisonous, and propionaldehyde gives an offensive odor. Recently, chemical analysis trends to be clean analysis. And so, it was re-studied on the determination of methanol. As the results, (1) the Na₂SO₃ was dissolved in distilled water, and (2) acetaldehyde-ammonia ([CH₃CH (NH₂) OH]₃) was replaced by propionaldehyde.
The recommended analytical procedure for methanol by the pararosaniline method is as follows:
Oxidized 10 ml of the test solution containing 3-80μg of methanol by adding 1 ml of 0.15 w/v% acetaldehydeammonia solution, 1 ml of 0.5 w/v% potassium permanganate solution, and 1 ml of 1.0 N sulfuric acid. Allow the mixture to stand at room temperature for 10 min. Add 1 ml of 1.2 w/v% sodium sulfite aqueous solution to reduce the excess of the potassium permanganate. Swirl, add 1 ml of pararosaniline hydrochloride solution (dissolved 0.16 grams completely in 24 ml of cone. hydrochloric acid, and dilute to 100 ml with water). Swirl, stand at room temperature for 90 min. Measure the absorbance at 580 nm against the reagent blank obtained by the same procedure.
The calibration curve is linear for 3-80 μg/10 ml of methanol. The coefficient of variation is 2.5%, the molar extinction coefficient being 5.4×103 mol^-1. cm^-1. dm³. A sample of vapor of methanol is passed at a late of 1 l/min through an impinger containing 10 ml of 0.005 N hydrochloric acid. With a sample period of 1 hour, a concentration as low as 0.03 ppm in atmosphere can be determined.

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As the relation between ozone concentration (C) and exposure time (T) which decides plant injury (I), in order to determine whether the relation of C²×T that we proposed on the previous studied is good or not, we exposed rice, soy bean, tobacco plants to the ozone in several conbinations of concentration-time which C²×T is constant. And we compared this relation with the relation of C×T that used commonly as Dose.
As a results, under the conditions of C²×T=constant, visible injury was nearly the same degree without mentioning and physiological injury such as ethylene evolution, chlorophyll decrease, MDA increase, K⁺ efflux was nearly the same degree. But under the conditions of C×T=constant, plant injury did not occurred the same degree, and plants exposed to higher ozone concentration occurred the injury more than low.
From these results, we recognized that the relation between plant injury and ozone concentration-exposure time was not linear but exponential relation, I=K (C²×T).
It is evident that the effect of photochemical oxidants on plants can be evaluated by the relation of C²×Tinstead of C×T.

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Air monitoring data indicates that the average oxidant concentration in Sapporo is higher in April and May than in summer months. According to the auther's analysis, it is found that these spring oxidant peaks are not produced by photochemical reaction near the ground but by the intrusion of stratospheric ozone.
Further, the intrusion of stratospheric ozone into boundary layer may largely contribute to the diurnal variation of oxidants in Sapporo with more than 40 ppb.
A simple photochemical smog model calculation also shows that the distribution of oxidant concentrationin Sapporo is controled by mixing from aloft rather than by photochemical process.

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Airborne particulates in urban Tokyo air were collected on the glass fiber filter paper by a high volume air sampler for 24 hours every day in January, April, July and October in 1980. Organic components in airborne particulates were extracted by the ultrasonic extraction method with benzene-ethanol (3: 1, v/v) as extracting solvent. Mutagenicities of these extracts were evaluated by the pre-incubation method using Salmonella typhimurium TA100 and TA98 strains with and without S-9mix. Polynuclear aromatic hydrocarbons (PAH: benzo-(a) pyrene, benzo (ghi) perylene, benzo (k) fluoranthene and perylene) contents were determined for the airborne particulate samples in January and July by one-dimensional dual band thin-layer chromatography and spectrofluorometry.
The extracts showed positive mutagenic response for both strains with and without S-9mix. Mutagenic activities estimated as revertant colonies per 1 m³ air changed more than 10 times even in a month. The data of mutagenic activities showed logarithmic normal distributions. Geometrical means ofmutagenic activities in winter (Jan.) and autumn (Oct.) were higher than those in spring (Apr.) and summer (Jul.), and the values with S-9mix were lower than those without S-9mix. The daily variations of PAH contents (ng per m³ air) were similar to those of mutagenic activities. Good correlations were obtained between PAH contents and mutagenic activities on both strains with and without S-9mix conditions.

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The cultures of bryophyte spores were investigated as a bioassay to evaluate the effects of air pollutants in rain water.
The spores were sown on an agar culture medium added with rain water or distilled water (control), and then cultured at 25±2°C with a 12 hours light period (1, 050-1, 300 lux.). The rate of the spore germination and the protonemal growth were compared with those of the control 10 days after sowing.
The results were as follows:
1) The spore germination and protonemal growth were scarcely inhibited on the medium at the range of pH 5-8, but markedly inhibited below pH 5.
2) Heavy metal ions in rain water such as Cu²⁺, Zn²⁺ and Mn²⁺ had synergistic or additive inhibition on the spore germination and protonemal growth in combination with sea salt (NaCl).
3) The bioassay using rain waters collected by means of deposit gauge for a month showed that the germination and germ tube elongation of the spores cultured with rain waters at the industrial areas were inhibited in comparison with the control.
From the above results, it can be demonstrated that the bioassay of germination and protonemal growth of the spores of epiphytic bryophytes on the agar culture medium is a sensitive indicator for evaluating air pollutants in rain water.

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In general speaking, it is well known that the cut-size X_c becomes to decrease with decreasing the diameter D₁ of the cyclone dust collectors. Here the cut-size X_c is defined as a particle diameter corresponding to 50% of the fractional collection efficiency η^x (X_p). But on the traditional theoretical formulae of the cut-size of the cyclone dust collectors, the cut-sizes are estimated by the representative sizes of the cyclone, namely, the outer diameter D₁ and the inner diameter D₂ and also mean inlet velocity V₀ in the inlet pipe without the restriction of the flow pattern of the three-dimensional turbulent rotational gas flow which depends on the sizes of the large, middle, small and miniature cyclones.
Therefore it appears to be a lack of understanding that, when the size of the cyclone becomes smaller and smaller, so the cut-size X_c becomes smaller and smaller due to increasing the centrifugal effect.
On the other hand, the author showed that the flow pattern in the cyclone changes with the cyclone Reynolds number R_cy= Q₀/H_iν, where Q₀ (m³/s) means the flow rate into the cyclone, H_i (m) is the imaginary cylindrical length and ν(m²/s) is the kinetic viscosity of gas.
Then the author (Europäscher Kongrepβ “Austauschprozesse in Partikelsystemen” Nürenberg, 28-30. März, 1977) derived the theoretical formula of the cut-size X_c basing upon the flow pattern of OGAWA combined vortex model, especially, the variation of the rotational flow of gas in the cyclone dust collectors as follows:
_??_
In this equation, n (1) is the velocity index, φ(1) is the shape factor of the solid particle, ξ(1) is the effective factor (ξ=0.333) of the inward air flow, η(Pa·s) is the viscosity of gas, A₀ (m²) is the cross-sectional area of the inlet-pipe, D₁ (m), D₂ (m) and D₀ (m) are the diameters of the outer cylinder (body), inner pipe and the inlet pipe respectively, Q₀ (m³/s) is the flow rate into the cyclone, and Q_b (m³/s) is the flow rate into the dust bunker which is a function of the diameter D₃ of the throat of the cone.
In this paper, using the experimental results of the cut-size X_c of Hochstrasser, J. M.(1976) Ph. D. “The Investigation and development of cyclone dust collector theories for application to miniature cyclone presamplers” and of Smith, W. B., Wilson, R. R., and Harris, D. B., (1979) “A Five Stage Cyclone System for in Situ Sampling” Environmental Science and Technology, Vol.13, No.11, 1979, pp.1387-1396, the author has compared the calculated cut-size X_c with the experimentally determined cut-size X_c50 of various kinds of the miniature cyclones.
Then, the calculated cut-size X_c is well coincided with the experimentally determined cut-size X_c50 And also, the author explained that even if the diameter D₁ of the cyclone becomes smaller, the cut-size X_c50 is not always decreased due to the increment of the viscous effect in the boundary layer on the wall surface of the miniature cyclones.

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[in Japanese]

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