Thiobacillus neopolitanus R-10, which produces a active thiosulfate oxidase, was isolated from nightsoil. The optimal culture conditions of Thiobacillus neopolitanus R-10 for the production of enzyme was determined as followed: 0.8% Na2S203, 0.2% KH2P04, 0.2% K2HP04, 0.04% Na2C03, 0.02% MgSO4·7H2O, 2ml trace elements solution, and pH 6.5 at 30℃ and 72hr cultivation. The oxidase was successively purified 83 folds yield by (NH2)2S04 fractionation, DEAE-Cellulose, Sephadex A-50 column chromatogrophy and gel Sephadex G-150 gel filteration with yield of 5.9%. The molecular weight of purified enzyme was estimated to be 43.000 dalton by SDS-polyacrylamide gel electrophoresis and gel filteration column chromatography. The enzyme activity was highest at 40℃ and pH 7.0 The enzyme activity was relatively high by β-mercaptoethanol but strongly inhibited by cysteine.

Continuous deodorization of malodorous sulfur compounds by Thiobacillus neapolitanus R-10 immobilized onto a polypropylene pellet was studied using a column reactor at 30℃. The maximum amounts of immobilized cells was 5.3 g/ℓ polypropylene with 5 × 7.5㎜ in pellet size, and the amounts of immobilized cells in the higher part of the column was as twice as in the lower part. The optimum pH and temperature for removal of dimethyl sulfide were 6.0 and 30℃, respectively. When 5-20 ㎕/ℓ of hydrogen sulfide and methylmercaptan were employed 98% of removal efficiency were achieved. In contrast, lower concentrations of dimethyl sulfide and dimethyldisulfide should be supplied to meet satisfactory deodorization efficiency. The immobilized cell column was successfully operated for the deodorization of mixture of sulfur compounds over 15 days without significant loss of initial activity achieving high efficiency.

Thiobacillus neapolitanus R-10 isolated from sludge of night soil, showed an oxidizing activity on several malodorous sulfur compounds. The microbe successfully utilized hydrogen sulfide(H_2S), methy mercaptan(MM), dimethyl sulfide(DMS) and dimethyldisulfide(DMDS) during the batch culture reaction, of which H_2S was rather rapidly oxidized. To examine the ability for removal of malodorous sulfur compounds, various concentrations of sulfide substrates were supplemented separately to basal medium and their responses were investigated. As the concentration of sulfide was increased, growth was accelerated within three days of cultivation. 2.5mM was the most favorable substrate concentration of sulfide added for all cases tested. However, when the concentration of sulfur compounds were raised over 4mM, they behaved as a growth inhibitor.

According to the report prepared by Legl Committee of IMO, 1978, since the disaster of motor tanker Amoco Cadiz carrying approximate 220, 000 tons of crude oil was wrecked on the coast of France and damaged the largest oil pollution accident in shipping history, Legal Committee of IMO has studied and discussed a new Salvage Convention with assistance of CMI. CMI has prepared a new draft convention under the chairmanship of professor Erling Chr. Selvig and adopted it as a report of CMI to IMO in the 32 Internaltional Conference of CMI, Montreal, May, 1981. This paper has been written to study comparatively andinterprete the questions and/or considerations of the new draft convention by the delegates participated in the Legal Committee of IMO in particular on the private legal view of it. This Salvage Convention Draft has not yet been deliberated thoroughly to agreed the revisiion of the 1910 Convention in accordance with CMI Report 1981 until session 54, March 1985. Therefore this paper has been prepared in the light of the comments made at the Legal Committee in order to interpret the legal questions and contents of the new draft.

우리나라 수도 품종의 시대적 변천에 따른 그들 품종의 생육형질 및 수량구성형질들의 변이를 조사비교하여 앞으로 품종육성 및 재배기술 발전에 필요한 기초자료를 얻고자 연대별 주요품종을 5개씩 25개 품종을 공시하여 5대 품종군, 즉 circled11907년대의 재래품종들을 GI군, circled2 1920년대의 도입품종들을 GII군 circled3 1930년대에 육성 보급된 품종들을 GIII군, circled4 1950년대에 육성 보급된 품종들을 GIV군, circled5 1971년 통일품종 육성이후에 육성된 품종들을 GV군으로 구분하여 이앙시기를 5월 15일, 5월 30일, 6월 14일 및 6월 29일의 4회로 하여 시험조사 하였는데 그 결과는 다음과 같다.