This technical review was described with regard to resarches and developments of methanol vehicles such as otto cycle types and diesel cycle types.

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This study was performed by use of oxidant data obtained at Mt. Unzen Nodake (1, 142 m) and Miiraku in Goto islands from April to September in 1981 and at the 24 monitoring stations in the Nagasaki prefecture during 1981-1984.
The results of the study were summarized as follows:
1) Oxidant concentration obtained at Mt. Unzen Nodake showed background ozone concentration from April to September in the period of observation.
2) Ozone destruction by NO and deposition to the surface was suggested. Oxidant between June and September was formed from NOx from man-made sources by photochemical reactions. As a results of these effects, oxidant concentrations showed various levels and time variation depending on the location of the stations.
3) The stations were grouped into 5 categories according to NOx concentration and patterns of diurnal variation of oxidant concentration.
4) Variation of background ozone concentration obtained Mt. Unzen Nodake and Isanoura (monitoring station) correlated with variation of surface pressure pattern. 10 typical patterns of them were observed.

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Column concentration-high performance liquid chromatography with spectrofluorometric detection has been studied for the ultratrace analysis of PAHs in micro amount of airborne particulates collected by personal samplers.
The developed method allowed to inject 0.5ml of sample solution without any damage on the separation of PAHs and without tedious procedures. Large volume sample injection made it possible to utilize 1/6 of PAHs collected on a filter for the determination, which largely improved the overall sensitivity in the analysis of PAHs in micro amount of airborne particulate samples. Detection limits of PAHs by the present analytical procedure are 18 pg for benzo (a) pyrene in a airborne particulate sample, 42 pg for benzo (k) fluoranthene and 60 pg for benzo (ghi) peryrene.
Ultratrace analysis of PAHs in airborne particulate samples collected by personal samplers (sampling: 200 ml/min × 24 hr) has been performed by the present method.

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In order to verify the availability of lichen substances as an indicator of combined air pollution, Parmelia tinctorum, epiphytic lichen sensitive to air pollutants, was collected around a steelworks in the Eastern Harima region. And, twelve components including lichen substances such as Atranorin and Lecanoric acid extracted from the thallus were analyzed.
As a result, concentrations of the lichen substances increased with the distance from the steelworks in contrast with other ten components.
Besides, Lecanoric acid content in P. tinctorum was inversely proportional to the atmospheric SO₂ concentration and a significant correlation between the Lecanoric acid and soluble trace element such as Pb²⁺, Zn²⁺, Mn²⁺, Fe³⁺ in rain water was found.
These results suggested that lichen acid in P. tinctorum was useful as an indicator of combined air pollution.

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An evaluation of the air pollution was discussed by heavy metals accumulation in Bryum argenteum Hedw., Samples distributed widely were collected from industrial, urban and rural sites in Okayama city and its area. Concentrations of inorganic elements in Bryum argenteum Hedw. were analyzed by using Neutron-activation method. The data resulted that, in industrial area, the concentrations of man-made inorganic elements such as antimony in aerosol were relatively high in Bryum argenteum Hedw.
Concentrations of mercury in Bryum argenteum Hedw. were also analyzed by flameless atomic absorption spectrophotometry with a combustion-gold trapping-heat vaporization technique. The single correlation coefficient showed strong relationship between mercury and antimony. This suggested that amounts of heavy metals such as mercury in Bryum argenteum Hedw. were able to be used as an indicator of air pollution instead of distribution of epiphytic lichen.

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A detail study on suspension phenomena of particles from wall surface was conducted to develop a model for simulation purposes. The renewal model, proposed by Nakagawa etal., was adopted to express the bursting phenomena of cyclic motion since the suspension of particles is initiated by the motion of fluid near the wall surface. It was shown that the local ejection current could be described well by the model.
A mathematical model was developed for each of the three mechanisms for initiation of the movement of particles; these being sliding, rolling and lift-up. Critical friction velocity at which the particle starts to move was estimated for each of these three forms of mechanisms by using models.
The investigation has shown the following; the model for motion in sliding form is capable of simulating the experimental results that the minimum critical friction velocity is observed at the particle diameter of approximately 0.01 cm, the model for motion in rolling form can describe the effect of surface roughness, and the model for motion in lift-up form, which includes the newly proposed lifting ability index, can quantitatively simulate that smaller particles tend to start the motion due to lift-up than sliding.

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During the period from Jun., 1985 to May, 1986, dustfall samples with rain water were collected by simple deposit gauge in Nara city and Mt. Ohdaigahara and the amount of deposits of fifteen metal elements (Na, Mg, Al, P, K, Ca, Ti, V, Mn, Fe, Cu, Zn, Sr, Cd, Pb) were measured by inductively coupled plasma emission spectrometry [ICP-AES]. And the chemical mass balance method [CMB] and the principal component analysis [PCA] were carried out with respect to these amount of deposits.
The metal elements in dustfall were mainly six species such as Ca, Na, Al, Fe, K, Mg and the amount of deposits of those decreased according to clean area from urban area.
The form of existence of metal elements in dustfall were mainly particle form for Al, Ti, and Fe and mainly soluble form for Na, Ca and Sr.
By the use of CMB, as the generated sources of metal elements of dustfall, the contribution rate from soil, sea salt and artificial sources were estimated to each metal elements.
As a result of PCA, the amount of deposits of metal elements was able to characterized with three principal components (Z₁, Z₂ Z₃). The first principal component Z₁ was considered to be a factor indicating the degree of synthetic amount of deposits. The second principal component Z₂ was a factor indicating the contribution of sources such as natural and artificial sources. The third principal component Z₃ was a factor indicating the contribution of sources such as soil and non-soil sources within natural sources. The degree of synthetic amount of deposits, the contribution of sources of metal elements of seasonally and locational distinction and the classification of metal elements were possible to evaluate by the use of these three principal components of Z₁, Z₂ and Z₃.

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The volcanic ashes erupted from Mt. Sakurajima were colleted together with rain water monthly from April 1984 to March 1987 at 14 locations in Kagoshima city and 7 locations in Sakurajima.
After the sample had been filtered, the residue was dried and weighed while the filtrate was analized for SO₄^2-, Cl^- and pH, and it was distilled and the resulting residue was taken as water-soluble matter.
The amounts of sulfur oxides absorbed on PbO₂ candle were measured at the same 19 locations (except for 2 locations in Sakurajima) as with ashfall measurement.
The average amounts of volcanic ashes in the last three fiscal years were 316 and 3, 370 ton/km².month at 14 locations (in Kagoshima city) and at 7 locations (in Sakurajima), respectively. Both average amounts were considerably larger than those in the previous three fiscal years (1981-1984) (112 and 2, 040 ton/km₂. month, respectively). Especially, during the summer in 1985, Sakurajima volcano was greatly active. The amount of volcanic ashfall recorded at Kurokami Middle School in September 1985, 77, 200 ton/km₂. month, was the highest in those recorded at all locations in the last nine years.
As for the sulfur oxide pollution, Sakurajima region was fairly polluted. In February 1986 at Arimura Haisuichi, the highest amount in the last three years was observed (3.10mg/ 100 cm²-day).
Acidation of rain was observed at all locations, and the highest acidity of the rain was in terms of pH 2.6 which was recorded both at Komen Elementary School and at Sakurajima Hospital in November 1986.

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