간행물
한국환경과학회지 KCI 등재 Journal of Environmental Science International
- 발행기관 한국환경과학회
- 자료유형 학술지
- 간기 월간
- ISSN 1225-4517 (Print)2287-3503 (Online)
- 수록기간 1992 ~ 2023
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제6권 제2호 (1997년 4월) 11건
1.
1997.04
서비스 종료(열람 제한)
The characteristics on the transtion probabilities and periodicity for the daily precipitation occurrence in Korean peninsula are investigated by applying the Markov chain properties to daily precipitation occurrence. In order to examine the responses of Markov Chain properties to the applied period and their magnitudes, three cases (Case A: 1956∼1985 at 14 stations, Case B: 1965∼1994 at 14 stations, and Case C: 1985∼1994 at 63 stations) are considered in this study.
The transition probabilities from wet day to wet day for all cases are about 0.50 and in summer, especially July, are higher. In addition, considering them in each station we can find that they are the highest at Ullung-do and lowest at Inchon for all cases. The annual equilibrium probabilities of a wet day appear 0.31 in Case A, 0.30 Case B, and 0.29 Case C, respectively. This may explain that as the data-period used becomes shorter, the higher the equilibrium probability is. The seasonal distributions of equilibrium probabilities are appeared the lowest(0.23∼0.28) in winter and the highest(more than 0.39) in spring and monthly in July and in October, repectively. The annual mean wet duration for all cases is 2.04 days in Case A, 1.99 Case B, and 1.89 Case C, repectively. The weather cycle obtained from the annual mean wet and dry duration is 6.54∼6.59 days, which are closely associated with the movement of synoptic systems.
And the statistical tests show that the transitions of daily precipitation occurrence for all cases may have two-state first Markov chain property, being the stationarity in time and heterogeneity in space.
2.
1997.04
서비스 종료(열람 제한)
The purpose of this study was to examine the questioning styles in middle school environmentology textbook in terms of frequency, type, and placement of questions. It was also to analyse and to compare the kinds of scientific inquiry processes elicited by the questions in the topics of textbooks.
The instrument was the Textbook Questing Strategies Assessment Instrument (TQSAI) developed the Cooperative Teacher Preparation Project, University of California.
The average number of questions per topic was only 1.09 and the ratio of questions to sentences was 2.5%. Most of questions were in explanatory place(75%). Nearly 90% of experienced questions types were reasoning or application. The frequencies of non-experiential question were higher than those of experiential question. In action, there were much kinds of question-styles.
3.
1997.04
서비스 종료(열람 제한)
The basic mechanism of the granular sludge formation which is the most important factor in the start-up and stable operaton is not confirmed yet. In this study, the effect of granular sludge formation was investigated with the different substrate concentrations and the various ratios of substrate supply/deficiency. The granular sludge formation in the UASB reactor was closely related to the substrate concentrations and the ratio of substrate supply/deficiency. The granular sludge formation was not accelerated at low substrate concentration. It was convinced that granular sludge formation was accelerated when the substrate supply with high concentration was stopped at UASB reactor. From this experiment, it was estimated that granular sludge was formed by the combination of hydrogen utilizing bacteria that form hydrogen condition and acid forming bacteria at substrate deficit condition by mutual symbiosis. Though the removal efficiency of organic matter was decreased as the influent substrate concentration was increased, the higher the influent substrate the better the granular sludge formation.
4.
1997.04
서비스 종료(열람 제한)
The mechanism of stomatal closing in response to O_3 was indirectly investigated by using H_2O_2 which is the intermediate product of O_3 metabolites. Stomata in epidermal strips close in response to H_2O_2. The effect of H_2O_2 on stomatal closing was dependent on the concentration of H_2O_2. 10 ppm H_2O_2 showed a clear effect on stomatal closing and 1000 ppm H_2O_2 induced complete stomatal closing after the treatment of 3 hours. Stomatal closing by H_2O_2 in intact leaf was also observed by measuring the diffusion resistance with porometer. It was found that the stomatal closing by H_2O_2 was not mediated by Ca^2+, and that was a different result observed in stomatal closing by water stress. Reversely, Ca^2+, showed a great inhibition on stomatal closing. The leakage of K^+ in epidermal strips was doubled in response to H_2O_2 when it was campared to the control. 10 ppm H_2O_2 decreased photosynthetic activity. Fv/Fm representing the activity of Photosystem Ⅱ was reduced about 4 % in 10 ppm H_20_2 and 8 % in 100 ppm H_2O_2 in the treatment of 1.5 hour. However, stomatal closing by 10 ppm H_2O_2 was reduced about 56 %. Accordingly, it can be suggetsted that stomatal closing by H_2O_2 is related with the decrease of photosynthetic activity, but it was chiefly induced by the change of the membrane permeability.
5.
1997.04
서비스 종료(열람 제한)
The solvent extraction method was applied on the wastewater produced during malonate(malonic acid esters) process to recover cobalt. DEHPA and PC88A were used as organic solvent. From separation funnel experiment(batch experiment), the effects of various parameters (pH, cobalt concentration, reaction rate, and stripping temperature) on solvent extraction were examined and these data were used to derive equilibrium curve. A mixer-settler experiment (continuous experiment) of bench scale was also carried out for the plant construction and a McCabe-Thiele diagram was obtained. The results of these experiments indicate that cobalt is recoverable above 99 % and that its purity as cobalt sulfate is higher than 99.9 wt %.
6.
1997.04
서비스 종료(열람 제한)
The pilot plant had been made so as to be an association system from the various items managed to have degrees of efficiency and it have been done to consider the experimental result with irradiance period and pH influence of all major things to treatment function of Waste Stabilization Pond. The results are as following.
The attained results for continuous & cyclic irradiance
1. 24L.-reactor was prior to 12L.-12D.-reactor on oxygen generation & algal production ability. 2. 24L.-reactor was prior to 12L.-12D.-reactor on nutrients removal efficiency. 3. In 24L.-reactor it maintained 5 ㎎/L∼6 ㎎/L, DO concent. enough to a fish`s survival.
The attained results for pH condition
1. Oxygen generation & algal production in pH 4-reactor were higher than those in pH 10-reactor. 2. The acidic condition at pH 4 and alkalic condition at pH 10 did not so much affect an algal growth and nutrients removal.
The attained results for whole
1. In view of the results appeared as [(NH_3-N)+(NO_3-N)] removal efficiency, 89.1%∼93.9% and PO_4-P removal efficiency, 34.3%∼83.7% & COD removal efficiency, 88.5%∼93.9%, It is possible to treat the wastewater with starch and pH which have been known as thedifficult problem. 2. At the point of non using methanol to nitrificate NO_3-N, the nutrients removal method by using an algal growth is the most economical method in the whole nutrients removal methods. 3. The nutrients removal method by using an algal growth contributes to natural ecosystem. 4. The nutrients removal method by using an algal growth is excellant in the prevention against the eutrophication.
7.
1997.04
서비스 종료(열람 제한)
In order to find the most fitted biodegradation model, biodegradation kinetics model to the initial phenol and p-cresol concentrations were investigated and had been fitted by the linear regression. Bacteria capable of degrading p-cresol were isolated from soil by enrichment culture technique. Among them, strain M1 capable of degrading p-cresol has also degraded phenol and was identified as the genus Micrococcus from the results from of taxonomical studies. The optimal conditions for the biodegradation of phenol and pcresol by Micrococcus sp. M1 were NH_4NO_3 0.05%, pH 7.0, 30℃, respectively, and medium volume 100㎖/250㎖ shaking flask. Micrococcus sp. M1 was able to grow on phenol concentration up to 14mM and p-cresol concentration up to 8mM. With increasing substrate concentration, the lag period increased, but the maximum specific growth rates decreased. The yield coefficient decreased with increasing substrate concentration. The biodegradation kinetics of phenol and p-cresol were best described by Monod with growth model for every experimented concentration. In cultivation of mixed substrate, p-cresol was degraded first and phenol was second. This result implies that p-cresol and phenol was not degraded simultaneously.
8.
1997.04
서비스 종료(열람 제한)
The floristic characteristics and ecological conservation measures for the plant resources of the Mt. KumJung(801m), Pusan, Korea were discussed. The field works was done for about twenty times in nine major areas from March, 1995 to Octover, 1996.
The total number of vascular plants in this area were summarized as 103 families, 312 genera, 493 species and 564 kinds. The fourteen kinds of artificially planted, ten kinds of Korean endemics and twenty-nine kinds of Korean rare and endangered species in the area were revised and compiled in the list.
The flora of the area were categorized into the South-coast part of the Korean Region, where the species such as Platycarya strobilacea, Quercus serrata, Eutya Japonica, Camellia japonica, Trachelospermum asiaticum var. intermedium, Quercus acutissima were roled as major floristic components in the Korean Region and endemized in the south-cosat part of Korea.
The natural communities such as Pinus thunbergii Community, Quercus mongolica community, Carpinus laxiilora Community, Wistaria floribunda Community and swamp vegetation in Bukmun area as well as upland grassland at the summit of Kodangpong were represented for their floristic values in the area.
The thirty kinds of medichinal plant, fifteen kinds of ornamental plants and thirteen kinds of edible plants are faced potentially in endangered from the outrageous collections by the local peoples. The action plan for the conservation management of the area which enables sustainable use by the local peoples must have established in the near feature.
9.
1997.04
서비스 종료(열람 제한)
The bacterial strains, which utilizes 2,4,4`-trichloro-2`-hydroxydiphenyl ether(TCHDPE) as a sole carbon source, were isolated by selective enrichment culture from soil samples of industrial waste deposits. The bacterium that showed the highest biodegradation activity was designated as EL-047R. The isolated strain EL-047R was identified as the genus Pseudomonas from the results of morphological, cultural, and biochemical tests. The optimum conditions of medium for the growth and the degradation of TCHDPE were TCHDPE 500 ppm, (NH_4)_2SO_4 0.1% as the nitrogen source, initial pH 7.0±0.1, and 37℃, respectively. In this conditions, the degradation rate of TCHDPE was about 97%. Pseudomonas sp. EL-047R was tested for resistance to several metal compounds and antibiotics. Pseudomonas sp. EL-047R was moderately grown to Cd(NO_3)_2, ZnCl_2, AgSO_4, CuSO_4 and HgCl_2. This strain was sensitive to rifampicin and kanamycin but resistant to ampicillin, penicillin, tetracyclin and chloramphenicol. Pseudomonas sp. EL-047R was grown structurally related compounds and potential metabolites of TCHDPE, and has the stability on TCHDPE biodegradation.
10.
1997.04
서비스 종료(열람 제한)
Organophosphate pesticides were extracted with 70% acetone and then transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil The final extract was analyzed by gas chromatography with nitrogen-phosphorus detector(GC/NPD). Recoveries of the 18 organophosphate pesticides were ranged from 88.7% to 100.0% for the narrow-bore capillary GC(Ultra-2). The minimum detectable level of this analytical method was 0.019 - 0.035 ㎎/㎏. Sample throughput(extraction, open-column chromatography, and GC analysis) was decreased considerably (8h per sample).
11.
1997.04
서비스 종료(열람 제한)
Toxic peptides from hornet venom, mastoparan and mastoparan-B were synthesized using the solid phase peptide synthesis method and investigated the interaction of them with phospholipid bilayer, antibacterial activity, and hemolytic activity. Both toxic peptides could induce dye release at a low concentration in neutral liposome. The binding affinity of mastoparan-B for neutral liposome was smaller than that for acidic one. Mastoparan and mastoparan-B had strong antibacterial activity for gram-positive bacteria, but weak or potent activity for gram-negative ones, respectively. Mastoparan and mastoparan-B lysed erythrocyte very little up to 5 μM.
