With the help of mechanical mixing method such as Banbury mixer and open 2 roll mill, ethylene propylene diene terpolymer (EPDM) was blended with the chloroprene rubber (CR) then mechanical properties and ozone resistance test of blends were subsequently investigated. It was noted that the hardness increased with an increasing of CR contents. Generally the hardness was increased with heat aging time most likely due to the post cure. In ozone resistance test of blend, after 8 hours a portion of fine crack is obtained for pure CR. It is confirmed that ozone resistance is greatly improved by addition of 25wt% EPDM to CR.

The education effect of environmental impact cognitive instruction on high school students was investigated. Environmental values of students could be classified into egocentric, social-altruistic and biospheric values like those of Schultz's three kinds of categories. The value distribution of students consists 44.7% of egocentric and biospheric value groups and 12.5% of social-altruistic value group, respectively. The environmental function such as knowledge and skill did not show remarkable differences between value groups. The environmental value only affected the attitude function. The biospheric value group had the higher attitude function than other value groups. The environmental impact cognitive instruction enhanced the environmental functions irrespective of the value group or instruction type. However, significant variables were different according to environmental functions. Environmental functions such as knowledge and skill were influenced by the instruction itself. The attitude function was dependent on instruction itself, value type and instruction type. The optimum application of the environmental impact cognitive instruction can be efficiently achieved through class division into egocentric value group and biospheric value group. Alternatively, the proper combination of instruction methods focused biospheric and egocentric impacts in a class can be recommended.

땅콩의 완전종실생산을 위해서는 150-180일의 생육기간이 소요되나 풋땅콩용으로 출하하면 총생육일수를 20-30일 정도 단축할 수 있을 뿐만 아니라 수확후 지상부 잔존유기물도 많이 남게 된다. 땅콩재배기간 단축에 따른 풋땅콩-무, 보리, 마늘과의 relay-cropping system에서 수확후 잔존 유기물의 토양환원 유무에 따른 각 작물들의 생육과 토양의 이화학성, 미생물상의 변화양상에 관한 기초자료를 얻어 남부지역 풋땅콩 안정생산기술을 확립하고자 수행한 시험결과를 요약하면 다음과 같다. 1. 작부체계별 시험후 토양경도는 풋땅콩 단작에서 가장 높았고, 토양 공 극율은 풋땅콩 단작 대비무, 보리, 마늘과 2모작 작부체계 처리에서 높 았으며 수확후 잔존유기물을 환원하였을 때 더욱 높아졌다. 2. 단작의 풋땅콩은 보리, 마늘과 2모작 작부체계상에서 재배된 풋땅콩에 비하여 도복 및 병 발생이 심하였다. 작부체계별 풋땅콩 수량은 단작에 비하여 풋땅콩-보리 및 풋땅콩-마늘 작부체계에서 증수하였으나, 유기 물 환원에 따른 수량 차이는 없었다. 3. 풋땅콩 후작의 마늘과 보리의 수량은 유기물 환원에 의하여 증대되었다. 4. C/N율이 높은 보리짚의 토양 환원에서 질소무기량이 증가하였고, 풋땅콩-보리와 풋땅콩-마늘의 작부체계에서 Pseudomonas spp.균 및 Trichoderma spp.균의 밀도가 높아져 풋땅콩의 친환경 작부체계로 추정되었다

To provide evidence that the changes in oceanic environmental conditions are useful indices for predicting stock structure and distribution of the Pacific saury (Cololabis saira), the body length compositions and catch per unit fishing effort were examined in relation to the sea surface temperature(SST) anomalies in the Tsushima Warm Current(TWC) region. The size of the fish became larger(smaller) than the average in the same size category during the season of higher SST(lower SST) as opposed to the normal SST. The year-to-year changes in body size caused by the changes in the environmental conditions led the stock to be homogeneous during the period of high stock level from the late 1950s to early 1970s and in the 1990s. The changes in body size manifested by higher(lower) occurrence rates of larger (smaller) sized groups in relation to temperature anomalies suggest that the changes in the environmental conditions affect the distribution and the structure of the stock in the TWC region. Therefore, if the SST anomaly derived from satellite data is large enough in the early spring months(Mar. or Apr.), it is possible to predict whether or not sea temperature will be favorable for large sized groups of saury at normal or slightly earlier time of commencement of the fishery in spring(Apr.～June).

This study examined blends of styrene butadiene rubber(SBR) and chloroprene rubber(CR) prepared from an open 2-roll mill following the conventional polymer blend method for a wide range of the blend composition. Rubber vulcanizates were manufactured by hot press and then mechanical properties, heat and ozone resistance of the specimens were examined. Due to the post cure during the aging test, hardness of vulcanizates was increased. It was found that the undesirable characteristics of heat and ozone resistance of pure SBR was significantly improved through the blending of SBR with CR.

The purpose of this experiment is to prepare ethylene propylene diene terpolymer(EPDM)/acrylonitrile butadiene rubber(NBR) blend which represents good environmental resistant properties including favorable oil and ozone resistance. With incorporation of EPDM, NBR and other ingredients, the rubber and chemical additives were mixed by mechanical method such as Banbury mixer and open 2-roll mill. Then rubber vulcanizates were manufactured by hot press and mechanical properties, oil and ozone resistance of the test specimens were measured. The oil resistance and ozone resistance of EPDM and NBR, respectively, is remarkably improved by blending EPDM with NBR. The optimum results of oil and ozone resistant characteristics were obtained at EPDM/NBR(=25/75 wt%) composition ratio.

This study was carried out to determine the antimutagenic effects of genistein on the somatic mutagenicity induced by aflatoxin B1 (AFB1), using Drosophila wing spot test system. Mutagen alone or mutagen with genistein were administered to the heterozygous(mwh/+) third instar larvae by feeding, and somatic cell mutations were detected in adult fly wing hairs. Genistein did not show any mutagenicity with the feeding concentrations of 5∼15% in the test system. As the feeding concentrations of genistein increased, genistein inhibited the mutagenicity induced by AFB1 (14.6%∼62.2% inhibition rate), while as the concentrations of AFB1 increased, small mwh spots that arise mostly from chromosome deletion and nondisjunction were more strongly suppressed by genistein than the large mwh spots from chromosomal recombination. In each group of different AFB1 concentrations, the rate of inhibition for total mwh spots was dependent on the dose of genistein. These results indicate that genistein have inhibitory effect on the mutagenicity induced by a mutagen, AFB1. It seems to suggest that genistein may exert inhibitory effects to mutagenic and/or carcinogenic properties of DNA damaging agents.

지황(Rehmannia glutinosa)의 국내 수요증가와 재배확대에 따른 우량 신품종 육성의 기초자료를 얻고자 몇몇 지황속 식물의 작물학적 특성을 조사하고, 재배환경이 지황의 생육 및 수량에 미치는 영향을 조사한 결과는 다음과 같다. 지황종 식물의 학명은 Rehmannia glutinosa Libosc, Rehmannia glutinosa Libosc var. purpurea Makino 및 Rehmannia glutinosa Libosch var. hueichingensis (Chao et Schih) Hsiao 등으로 지상부 생육특성과 뿌리의 작물학적인 형태는 다양한 차이를 보였다. 중국으로부터 도입 육성한 지황 1호는 근경이 굵고 다수성이고 일본종은 가늘며 깊게 신장하는 특성을 보였으며 국내재래종은 중간형질을 지니고 있었다. 지황1호를 공시하여 적정재배 환경을 조사한 결과 지황의 근비대 생장은 7월 중하순경에 근중과 근경 모두 급속하게 증가함을 보였고, 일장과 온도는 제한된 3처리중 13시간 일장에서 주간 23℃ 야간 18℃ 처리에서 근비대 생장이 가장 양호 하였다. 토양은 양토조건에서 2,144kg/10a로 가장 높은 수량성을 보였고 토양수분이 60~70%에서 근비대 생장이 양호하였다.

This study was conducted to investigate the effects of environmental factors such as temperature, salinity, pH, and UV light on the survival of life-threatening Vibrio vulnificus. In the temperature range of 15 to 25℃, the numbers of V. vulnificus increased during the 6-day incubation, but outside this range, the survival of V. vulnificus was poor. Incubation between 1 and 10℃ showed that V. vulnificus survived poorly below 10℃. At salinities between 5 and 25ppt, the numbers of V. vulnificus increased or remained unchanged for 6-day. At salinities above this range, the numbers of V. vulnificus decreased. The optimal pH range was 6.5 to 8.0 and outside this range, the survival ratio of V. vulnificus was small. At 15 and 25℃, UV radiation was bactericidal for cultures of V. vulnificus. The counts of V. vulnificus were reduced approximately 10,000-fold after 2h of UV light treatment at both temperatures. Above results showed that environmental factors were effective on the survival of V. vulnificus in the environment.

This study examines the development and management of the Herb Island in Japan, and explores influences of the herb garden on a rural community. The result suggested that the development of a herb garden can make a major impact on a rural community's econmoic stability and growth, and low-input cultivation of herbs serves to the ecosystem and soil conservation. In order to foster the herb industry in Korea, three aspcets should be considered. These are as follows. 1. Selection of suitable kinds of herbs and sites for Korean natural environment,and planning for proper landuse should be carried out first. 2. Proper policies for a herb garden to help local economy should be established. 3. Development of programs and experts on environmental education should be included in planning herb gardens in order to contribute to natural environment preservation.

토양수분, 질소시비량 및 도복의 발생 유무가 소맥엽신의 기공개도에 미치는 영향을 알고져 소맥 조광 품종을 공시하여 침윤법으로 개화기에 기공개도의 일중변화를 조사하였던바 그 결과는 다음과 같다. 1. 기공이 폐공되는 시각은 토양수분 Potential이 낮을수록 빨라졌으며 폐공되는 정도도 컸었다. 2. 기공개도는 하위엽이 상위엽에 비하여 작았고 토양수분 Potential 이 낮을수록 기공개도의 감소정도는 더욱 컸다. 3. 도복된 맥체의 기공개도는 정상 맥체에 비하여 작았는데 그 경향은 토양수분 정도 및 측정시각에 관계없이 동일하였다. 4. 질소 보비구는 소비구에 비하여 기공개도가 큰 일중변화를 하였는데 도복구나 건조구에서도 같은 경향이었다. 5. 도복후 일수가 경과함에 따라 기공개도는 크게 감소하였는데 도복후 6 일에는 무도복구에 비하여 50％이하의 개도를 보였으며 그 감소정도는 하위엽이 더욱 컸으며 일중에서는 오후에 현저하였다.

질소의 추비가 소맥엽신의 기공개도에 어떠한 영향을 미치는가를 검토하기 위하여 소맥 조광 품종을 공시하여 질소추비와 무추비구로 처리하여 침윤법으로 최고분얼기, 절간신장기, 수잉기, 개화기, 등숙중기에 기공개도를 측정하였던바 그 결과는 다음과 같다. 1. 소맥엽신의 기공개도는 생육이 진전됨에 따라 증가하여 개화기경에 최대에 달하였으며 그 이후는 저하하였다. 2. 1 일중 기공개도가 최대로 되는 시각은 각시기 모두 정오경이었으며 오후 6시경에는 상당히 폐공 되었으나 이는 생육단계에 따라 다소 상이하였다. 3. 질소의 추비는 엽신의 기공개도를 증가시켰는데 그 정도는 생육이 왕성한 수잉기와 개화기에 특히 큰 경향이었다. 4. 상위엽은 하위엽에 비하여 모든 생육단계에서 큰 기공개도를 나타내었으며, 질소추비에 의한 기공개도의 차이도 상위엽이 하위엽에 비하여 크게 나타나는 경향이었다. 5. 엽신의 질소함량과 1 일중 기공개도의 최대치간에는 고도의 정상관(r=0.66＊＊) 관계가 있었는데, 상위엽과 하위엽 모두 같은 경향이었다. 6. 각 엽기의 엽위간 기공개도의 차는 완전 전개한 최상위엽이 최대치를 나타내었고 전개중인 미성숙엽이나 엽의 노화가 진전된 하위엽일수록 기공개도는 작았다. 7. 각 엽신의 함수중, 근중 및 근의 활력은 질소의 추비에 의하여 증가되었는데 이는 기공개도를 증대시친 한 요인으로 작용한 것으로 추찰되었다.