Dry deposition fluxes were evaluated by both the surrogate and concentration methods from May 1995 to April 1996 at Dazaifu in Fukuoka. Dry deposition fluxes by the surrogate method were measured by the deposition amounts onto dry-surface and wet-surface in petri dishes exposed for one week interval. Dry deposition fluxes by the concentration method were estimated as the product of the atmospheric concentrations and deposition velocities. The atmospheric concentrations of components in the gas and particulate phases were measured by the filter pack method for one week interval.
Annual dry deposition fluxes of SO₄^2--S, NO₃^--N and NH₄⁺-N by the surrogate method on dry-surface were 290, 59 and 33mg m^-2 year^-1, respectively and on wet-surface 1090, 140 and 630 mg m^-2 year^-1, respectively. Annual dry deposition fluxes of SO₄^2- and NH₄⁺ on wet-surface were larger than those on dry-surface, due to the dissolution of SO₂ and NH₃ in water.
The annual mean concentrations of particulate SO₄^2- SO₄^2--S, NO₃^--N and NH₄⁺-N in air were 2.14, 0.72 and 1.89, μg m^-3, respectively, and those of gaseous SO₂-S, HNO₃-N and NH₃ -N were 6.48, 0.47 and 3.20 μg m^-3, respectively. Annual dry deposition fluxes by the concentration method were estimated to be 840 mgS m^-2year^-1 as (SO₄^2-+SO₂)-S, 550 mg N m^-2 year^-1 as (NO₃^- HNO₃)-N and 1500 mg N m^-2 year^-1 as (NH₄⁺+NH₃) N. Dry deposition fluxes from the gas phase were greater than those from the particulate phase.
The dry deposition flux of SO₄^2--S by the surrogate method was similar to that by the concenration method, but the dry deposition fluxes of NO₃^--N and NH₄⁺-N by the surrogate method were less than those by the concentration method, due to bouncing off the surface by wind and volatilization. Dry deposition fluxes of Cl^-, Ca²⁺, Mg²⁺, K⁺ and Na⁺, all main components of coarse particles, determined by the surrogate method were similar to those estimated by the concentration method. The contribution of SO₄^2-, NO₃^- and NH4+ dry deposition to the total deposition were 47%, 62% and 76%, respectively.

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The behavior of the chemical components of suspended particulate mater (SPM) in a mountainous area were investigated. A special attention was paid on the seaconal and diurnal variations of the secondary particulate. The sampling site was Happo at an altitude of 1850m, in the centratl mountainous region of Japan.
Sulfate was the most abundant particulate and accounted for 20% of the SPM, followed by organic carbon (OC) (8%), NH₄⁺ (5%) and elemental carbon (EC) (4%). The concentrations of SO₄^2-were much higher from April to July than those from October to March, and these variations were similar to those of ozone, suggesting that almost all of the SO₄^2-was produced by the photo-oxidation of SO₂ and transported long distances. The ion balance between cations (NH₄⁺, Na⁺, Mg²⁺ and Ca²⁺) and anions (SO₄^2-, NO₃^-and Cl^-) tended toward anion excess, and equivalent concentrations of SO₄^2- were much higher than those of NH₄⁺ These results suggest that a portion of the SO₄^2-existed in the form of acidic aerosols such as HZSO₄ and NH₄HSO₄. Backward trajectory analysis suggected that the air pollutants in this mountainous area were transported not only from other regions of Japan, but also from continental Asia. Seasonal variations of T-NO₃ (total nitrate in gaseous and particulate matter), OC and oxalic acid concentrations were similar to those of ozone and SO₄^2-and the correlation coefficients with SO₄^2-were positive.These findings suggest that those components were produced by photochemical reactions. The secondary components, NH₄⁺, SO₄^2-, NO₃-and a part of the OC, accounted for more than 23% of the SPM from April to August.

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As part of an effort to develop a simple method for measuring odors using an odor sensor, we investigated sensor characteristics for individual odors, and applied evaluation of complex odors. In a study of 21 malodorous substances, which included 19 legally designated substances, we found a linear relationship between the logarithms of those substances concentrations and the odor sensor response values.
The sensitivity of the odor sensor used was quite good, because it was able to measure even concentrations below legal standard regulation values at facility site boundaries for sulfur compounds (except methyl mercaptan), organic solvents and acetaldehyde.
To measure complex odors, we conceived a method of predicting sensor response values from the concentrations of the constituent malodorous substances, and found that predicted values coincided well with measured values. When the ratios of the malodorus substances making up a complex odor are known, we deviced a method of estimating the concentrations of the constituent malodorous substances from odor sensor response values, and found that measured values coincided with predicted values.

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The averaged minimum temperature in August at Osaka City is rising about 2 degrees in 100 years. It can be considered that the cause induced heat island phenomenon is the increase of energy consumption and the alteration of the ground surface. In this study, we simulated the influence of the building configration on the wind velocity and potential temperature within the urban canopy layer, using one dimensional atmospheric boundary layer model. It was assumed that the building of the same size had been regularly arranged in the shape of a lattice within the urban canopy, and the shortwave radiation and long wave radiation fluxes in the urban canopy were independently estimated correctly by the photon tracking method based on the Monte Carlo method. When a fraction of an area covered with the buildings (η) increased or the urban canopy height (h_c) became high, it was found that the shortwave radiation flux which the ground surface receives at the daytime decreases, and the long wave radiation flux emitted to the sky decreases at the night time. Next, the heat budget equation model on the building and ground surface, and one dimensional atmospheric boundary layer model were combined, and the temperature and the wind velocity distribution in the urban canopy were predicted. Whenη increased or h_c became high, the wind velocity in the urban canopy decreased, and the potential temperature rise at the daytime became small and the potential temperature fall at the night time became also small. It became clear by these results that the increase of η and the rise of h_c are one of the causes of the heat island phenomenon.

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Methyl bromide (MB) for soil fumigant was regulated as an ozone depleting substance, but MB for quarantine fumigation is not regulated and will be continued to consume. By literature, hearing and questionaire, realities of quarantine fumigation and necessary conditions for recovery and destruction technologies are clarified as follows.
1) Consumption amount of MB for quarantine fumigation in Japan is c.a. 2, 400 t/y, and over half of it is for log, 30% is for cereals, the rest is for vegetables, fruits and others. 2) Concentrations of MB after the fumigation for recovery or destruction are 5, 000-40, 000 ppm for log in tent, 1, 000-7, 500 ppm for cereal in silos and in storehouse, 6, 000-12, 000 ppm for vegetables and fruits in storehouse. 3) The amounts of MB for recovery or destruction at once fumigation are calculated 50-270 kg for log (5-15 tents), 17-46 kg or 110-260 kg for cereal in silos, 6-45 kg for cereal in storehouse, 4-59 kg for vegetables and fruits in storehouse. 4) To design equipment for recovery or destruction of MB, it needs to consider time for once fumigation, humidity of gas, and supplying power, water and steam. 5) Technologies for recovery of MB by adsorption and condensation and for destruction of MB by incineration, chemical reaction, catalytic oxidation, ozonation, pluzuma destruction are being investigated, but they need to be more effective and economical.

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