본 연구는 생분해성 용기 개발의 연구성이 대두됨에 따 라서 동물성 재료로 제조한 생분해성 용기의 개발의 목적에 있다. 연구 결과 돈피, 우피, 닭피에 있어서 돈피가 우수한 수율과 단백질 분자량을 가진 것으로 나타났다. 이에 돈피를 이용하여 생분해 용기를 개발하였으며, 단면적 확인 결과 호두 껍질 분말 10%를 첨가한 처리구에서 적은 공극을 보였으며, 호두 껍질 분말 20%를 첨가한 처리구에서 공극의 크기가 큰 것을 확인할 수 있었다. 물성 연구 결과 호두 껍질 분말 10% 처리구가 더 높은 경도를 나타 내었으며, 호두 껍질 분말 20% 처리구가 더 높은 탄력성을 나타내었다. 압축강도는 호두 껍질 분말 20% 처리구가 더 높은 값을 나타내었다. General bacteria, E. coli 연구 결과 모든 일자에서 불검출되어 미생물로부터의 안정성은 더 장기간으로 실험해볼 필요가 있을 것으로 보인다. 또한 높은 항균 능력과 생분해능의 결과를 보여 저장 기간의 안정성이 높은 용기의 개발과 환경의 영향을 최소화 할 수 있을 것으로 판단된다. 따라서 돈피 젤라틴에 난각과 호두 껍질 분말을 넣어 제조한 생분해성 용기의 개발의 기초 데이터로 이용될 수 있을 것으로 생각된다.

This study investigated the degradation characteristics and biodegradability of phenol, refractory organic matters, by injecting MgO and CaO-known to be catalyst materials for the ozonation process-into a Dielectric Barrier Discharge (DBD) plasma. MgO and CaO were injected at 0, 0.5, 1.0, and 2 g/L, and the pH was not adjusted separately to examine the optimal injection amounts of MgO and CaO. When MgO and CaO were injected, the phenol decomposition rate was increased, and the reaction time was found to decrease by 2.1 to 2.6 times. In addition, during CaO injection, intermediate products combined with Ca2+ to cause precipitation, which increased the COD (chemical oxygen demand) removal rate by approximately 2.4 times. The biodegradability of plasma treated water increased with increase in the phenol decomposition rate and increased as the amount of the generated intermediate products increased. The biodegradability was the highest in the plasma reaction with MgO injection as compared to when the DBD plasma pH was adjusted. Thus, it was found that a DBD plasma can degrade non-biodegradable phenols and increase biodegradability.

In order to investigate the effective pretreatment methods in WAS(=waste activated sludge) solubilization, the values of SCOD yield per unit SS (SCOD/gSS.hr) were compared. After the hydrodynamic cavitation with pH of 12.5, SCOD increased to 7800 mg/L, SS decreased to 45 % and the solubilization rate was 29 %. Combination of alkality (pH 12.5) and the cavitation seems to be the optimal condition for sludge solubilization. After the cavitational pretreatment, efficiencies of anaerobic digestion of the unfiltered sludge(the control), raw sludge and pretreated sludge were evaluated with BMP(=biochemical methane potential) tests.For evaluation of the biodegradability characteristics of pretreated sewage sludge, the methane production has been measured for 6 months. The methane production of pretreated sludge increased 1.4 times than that of untreated sludge. The result indicates that the cavitationally pretreated sludge was a better biodegradability substrate in anaerobic condition compared to raw sludge. It is obvious that cavitational pretreatment could enhance not only solubilization but also biodegradability of WAS. In conclusion, cavitational pretreatment of WAS to convert the particulate into soluble portion was shown to be effective in enhancing the digestibility of the WAS.

In order to evaluate the biodegradability of bait used in the pot for swimming crab, water tank experiments were conducted. Mackerel is the most commonly used natural form of bait to catch the swimming crabs, and therefore was used in this experiment for the biodegradability according to the manufacturing process of the bait. From the biodegradability test on chemical oxygen demand(COD), total nitrogen(T - N), total phosphorus(T - P), ammoniac nitrogen, nitrite nitrogen and nitrate nitrogen per unit weight of the bait based on the production rate and the accumulated amount of pollutants, it was concluded that the smaller the size of the mackerel pieces, the higher the production rate and accumulated amount of organic matter and nutrients which was unfavorable to water pollution. The amount of pollutants released from the intestine of the tuna was similar with that from the whole mackerel. For the operation period of 111 days, the accumulated concentrations of tested pollutants from the tuna which were 67.3 mgCOD/g d, 86.4 mgT N/g d, 3.1 mgT - P/g d, were almost half comparing with those from the mackerel which were 65.7 - 94.4 mgCOD/g d, 83.8 - 109.4 mgT - N/g d, 3.1 - 5.2 mgT - P/g d. The amount of pollutants released from the intestine of the tuna was slightly less than that from the mackerel that was cut into 8 pieces. but more than that from the mackerel which was not cut into pieces. Therefore, it can be concluded that the key factor in determining water pollution potential is not the kind of bait, but the processing or preparation method used.

As a pa rt 0 1' the effort to develop a suitable scaffold for tissue-engineered bone regene ration, we modified calcium metaphosphate(CMP) ce ramic with 5 mol% Na20 or K20 to improve t he biodegradability and evaluated their effi ciency as a biodegr adable scaffold for ti ssue-engineered bone regeneration. The macroporous αiIP ceramic blocks incor porated with 5 mol% Na20 or K20 were prepa recl to have average pore size of 250 um in an inte rconnectecl framework structure The influ e nce of inco r pora tecl 5 mol% Na20 or K20 on cytotoxicity‘ cellular attachmont and t heir clifferentiation was evaluated by in vit ro analyzing sys tern. res pectively. The bioclegradability, histocompatibility, and osteogenic effect by cell-scaffolcl co nstruc ts were evalua ted by im plantation of them into subcutaneous pouches of SD-rats 0 1' SCID ITllce The incorporation of 5 mol% Na20 or K20 causecl clecrease of compressive strength without improving of biodegr adabili ty . The moclifi ed scaffolcls revea led no cy totoxic and excell ent biocompatability but osteogneic effect was recluced compa red to pure CMP ce ramic porous blocks . These res ul Ls s ugge::;t tha t the incorporation of 5 mol% Na20 0 1' K20 into pure CMP is not effective for improv ing effï ciency 0 1' scaffolcls fo1' tissue-engineered bone regeneration in terms of bioclegradabi li ty‘ physical s trength . a ncl osteogenic rege ne ra tive effect

This study was aimed to investigate treatment feasibility of leachate from D landfill that is located in gyr대ungbuk. From the analytical results of leachate, organic and nonbiodegradable matters were contained in high concentration. Thus chemical treatment was introduced to degrade nonbiodegradable matters in pre or post biological process. Two types of Fenton oxidation were adapted in this study. The first one is pre treatment process before biological treatment. The second one is post treatment process after biological treatment. The optimal conditions of both treatment methods were investigated as follows. In case of pre treatment process, the optimal conditions appeared in Fe+2/H2O2(mmol/mmol): 0.1, H2O2/CODcr(mg/mg): 27.0, pH: 3 and reaction time: 2hrs. On the other hand, in case of post treatment process, the optimal conditions appeared in Fe2+(mmol/mmol): 0.14, H2O2/CODcr(mg/mg): 57.4, pH: 3 and reaction time: 1.25hrs. In the above optimal conditions, high COD removal was obtained in pre and post treatment process. Also it can expect that Fenton oxidation converted nonbiodegradable matters into biodegradable matters.

The present study was conducted to investigate biological degradability of phosphamidon and profenofos. In the biodegradation test of two pesticides by the modified river die-away method from May 20 to July 29, 1999, the biodegradation rate was determined in Nakdong (A) and Kumho(B) River. The residual percentages of phosphamidon were 74.9%, 68.8% and 62.7% in control, A and B samples 7 days after application, respectively. Biodegradation constants and half-lives of phosphamidon were 0.0005 and 58.6 days in A, 0.0012 and 23.8 days in B, respectively. The residual percentages of profenofos were 25.1%, 21.9% and 11.9% in cotrol, A and B samples 7 days after application. Biodegradation constants and half-lives of profenofos were 0.0005 and 58.4 days in A, 0.0013 and 21.6 days in B, respectively. The biodegradation rates of phosphamidon and profenofos were higher in the Kumho River(B) than in the Nackdong River(A). The strains of microorganisms for the degradation of phosphamidon and profenofos were identified as Klebsiella pneumoniae, Aeromonas hydrophila and Acinetobacter calcoaceticus, all Gram-negative bacteria. In order to identify biodegradate products, the extracts of cultivates were analyzed by GC/MS. The mass spectra of biodegradate products of phosphamidon were at m/z 153 and 149, those of the profenofos were at m/z 208 and 240, respectively. It was suggested that the biodegradate metabolites of phosphamidon were O, O-dimethyl phosphate (DMP) and N, N-diethylchloroacetamide, those of profenofos were 4-bromo-2-chlorophenol and O-ethyl-S-propyl phosphate.

Poly(3-hydroxybutyrate)의 표면 형태가 생분해성에 미치는 영향을 조사하였다. 용융 상태의 PHB를 서냉 (-0.5℃/min)시켰을 때 PHB의 결정화도는 액체질소 속으로 급냉한 후 90℃에서 2시간 동안 숙성한 PHB의 결정화도보다 높게 나타났으나 전자의 PHB 시료는 미세 균열의 존재로 인하여 후자의 PHB 시료보다 더 빠르게 생분해되었다. 거친 표면을 가진 평판 위에서 hot press하여 표면을

본 연구에서는 현재 국내에서 사용되고 있는 이분해성 미생물 분해성 시험방법의 문제점을 제시하고 이를 해결하거나 보완할 수 있는 방법을 제안하고자, OECD지침서에 등재된 6가지 이분해성 시험방법 중 시험물질의 선정에 제한이 없는 MITI(I), manometric respirometry, closed bottle test에 대하여 8개 화학물질을 대상으로 비교시험 하였다. 현재 국내에서는 MITI(I)법을 사용하고 있는데 이 방법은 접종미생물의 준비과정

As the result of the qualitative and quantitative analysis of the surfactant mixture, the main surfactant of the fast biodegradable detergent which were derived from vegetable oil was Sodium Lauryl Sulfate. The Detergents contained sodium lauryl sulfate, nonionic surfactant, soap, etc, as the rest sufactants. Linear Alkylbenzene Sulfonate and alpha-Olefin Sulfonate which were derived from petroleum were not detected. The biodegradation rate of the detergent prepared from vegetable oil was faster than that of the detergent derived from petroleum stood in 7 days.

Anaerobic mesophilic batch tests of energy crops (forage barley, rye, Italian ryegrass, and oats) were carried out to evaluate their ultimate biodegradability and two distinctive decay rates (k1 and k2) with their corresponding degradable substrate fractions (S1 and S2). Graphical statistical analysis and biochemical methane potential (BMP) tests showed that the ultimate biodegradability was 82 ~ 88% for forage barley, 70 ~ 77% for rye, 66 ~ 79% for Italian ryegrass, and 59 ~ 67% for oats. The readily biodegradable fraction (S1) of 73% of forage barley biodegradable volatile solid (BVS, S0) degraded within the initial 40 days at k1 of 0.055 day−1, whereas the slowly biodegradable fraction (S2) of BVS degraded over more than 80 days with long term batch reaction rates of 0.002 day−1. For oats, this readily biodegradable portion (S1) was 57%, which degraded with a k1 of 0.023 day−1 for the initial 60 days. The minimum hydraulic retention time (HRT) for the anaerobic digestion of forage barley, rye, and Italian ryegrass were estimated in the range 45 ~ 55 days and 65 days for oats.

Anaerobic mesophilic batch tests of food waste and food waste leachate collected from food waste treatment facility were carried out to evaluate their ultimate biodegradability and two distinctive decay rate coefficients (k1 and k2) with their corresponding degradable substrate fractions (S1 and S2), respectively. Each 3 liter batch reactor was operated for more than 60 days at substrate to inoculum ratio (S/I) of 0.5 as an initial total volatile solids (TVS) mass basis. Result of Ultimate biodegradability of 74 ~ 83% for food waste and 85 ~ 90% for food waste leachate were obtained respectively. The readily biodegradable fraction of 85 ~ 93% (S1) of food waste Biodegradable Volatile Solids (BVS, So) degraded within the initial 15 days with a range of of 0.151 ~ 0.168 day−1, whereas the rest slowly biodegradable fraction (S2) of BVS degraded for more than 53 days with the long term batch decay rate coefficients of 0.009 ~ 0.010 day−1. For the food waste leachate, the readily biodegradable portion (S1) appeared to be 92 ~ 94% of BVS (So), which degrades with of 0.172 ~ 0.206 day−1 for an initial 15 days. Its corresponding long term batch decay rate coefficients were 0.005 ~ 0.009 day−1. It is recommended that the hydraulic retention times of mesophilic anaerobic digesters be 16 days for the food waste and 15 days for the food waste leachate, respectively. However a safety factor should be considered when designing a full scale plant.

Anaerobic mesophilic batch tests of dairy cow manure, dairy cow manure/saw dust mixture and dairy cow manure/ rice hull mixtures collected from bedded pack barn were carried out to evaluate their ultimate biodegradability and two distinctive decay rates (k1 and k2) with their corresponding degradable substrate fractions (S1 and S2). Each 3 liter batch reactor was operated for more than 100 days at substrate to inoculum ratio (S/I) of 1.0 as an initial total volatile solids (TVS) mass basis. Ultimate biodegradabilities of 37 ~ 46% for dairy cow manure, 32 ~ 40% for dairy manure/saw dust mixture and 31 ~ 38% for dairy cow manure/rice hull mixture were obtained respectively. The readily biodegradable fraction of 90% (S1) of dairy manure BVS (So) degraded with in the initial 29 days with arange of k1 of 0.074 day−1, where as the rest slowly biodegradable fraction (S2) of BVS degraded for more than 100 days with the long term batch reaction rate of 0.004 day−1. For the dairy manure/saw dust mixture and dairy manure/rice hull mixture, their readily biodegradable portions (S1) appeared 71% and 76%, which degrades with k1 of 0.053 day−1 and 0.047 day−1 for an initial 30 days and 38 days, respectively. Their corresponding long term batch reaction rates were 0.03 day−1.

The biodegradable characteristics of poly-β-hydroxybutyrate(PHB) film by fungi and soil burial are investigated. As the results of the American Standards for Testing and Materials(ASTM) method, the growth of Aspergillus niger was apparent on the PHB containing plate. This suggests that PHB was utilized as the sole carbon source by Aspergillus niger and ASTM method may have applications as measuring means of biodegradability of polyhydroxyalkanoic acid(PHA). PHB film was studied by monitoring the time-dependant changes in weight loss of PHB film under 30℃ and relative humidity 80 % during pot-test. As the results of pot-test, PHB film was decomposed about 87 % in 30 days by soil microorganisms. PHB film was more slowly degraded than PHB/HV film.