• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.193-198
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• 2001

Preparation of antibacterial biopolymer film which is suitable for food packaging film was investigated using K-carrageenan as a base material. K-Carrageenan showed good biodegradability and film-forming characteristic but poor mechanical properties under humid condition. Also, various bacteria grew well on its surface. The poor mechanical properties could be improved by mixing with alginate at a 1:1 ratio and crosslinking with $CaCl_2$ solution. Antibacterial property coul be provided by modifying the K-carrageenan film surface with acrylic acid plasma followed by ion-exchange with $Ag^+$ ions. Such prepared film still showed good biodegradability by various fongi.

• Journal of Environmental Health Sciences
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• v.37 no.2
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• pp.159-164
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• 2011

We describe a method for effectively pretreating soil highly that has been contaminated with fluorene (${\gg}$ 120 mg/kg soil), i.e., we apply Fenton oxidation in which ethanol is added to increase fluorene removal. To obtain maximum fluorene removal efficiency, a minimum of 1.0 ml of ethanol, 0.35 ml of $H_2O_2$, and 0.2 ml of 0.5M $Fe^{2+}$ was needed per 1 g of fluorene-contaminated soil. Under optimal Fenton oxidation conditions, 13% of 9-fluorene was generated during Fenton oxidation of 43% fluorene. The biodegradability of 9-fluorenone was subsequently confirmed to be much more rapid than that of fluorene, i.e., biodegradability of 96% versus 35% over 31 days. These results demonstrate that the proposed treatment method can be effectively applied to remove fluorene prior to disposal at industrial waste sites.

• Journal of Environmental Science International
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• v.13 no.9
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• pp.827-833
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• 2004

The biodegradability of vinyl acetate acrylate resin and com starch blend was studied by determination of the reduced sugars produced after enzymatic hydrolysis. The starch hydrolysis reaction by $\alpha-amylase$ was achieved within 5 minutes. Optimal ranges of temperature and pH for the starch hydrolysis by $\alpha-amylase$ were around $80^{\circ}C$ and 6.5-7.2, respectively. The biodegradability of the starch-filled acrylate films increased as the content of starch increased. The biodegradation of starch in the starch-filled acrylate film by $\alpha-amylase$ was about 48.6% of that of pure starch. This value of biodegradable starch-filled acrylate film gave a good result with enzymatic shortcut test. The surface morphologies of the starch-filled acrylate film after enzymatic hydrolysis were investigated by scanning electron microscopy (SEM).

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.175-178
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• 2000

Biodegradability of the $poly({\beta}-hydroxybutyrate-co-3 -hydroxyvalerate)$ [PHB/V] containing 0, 10 and 15mol% hydroxyvalerate [HV] was studied. Bioderadability of PHB/V was evaluated at $30^{\circ}C$ for 58 days and $55^{\circ}C$ for 33 days by monitoring the time-dependent changes in weight loss(erosion) of aerobic conditions in a temperature-controlled microcosms containing the earthworm cast($30^{\circ}C$) and compost ($55^{\circ}C$). It was found that PHB/V biodegradability occurred with increasing HV monomer concentration from 0 mol% to 15 mol%.

• Journal of Environmental Health Sciences
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• v.21 no.4
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• pp.17-23
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• 1995

As a basic experiment to develope biological pretreatment proces~ in water treatment, the experiments on biodegradability and isothermal adsorption of activated carbon were performed on refractories such as humic acid, $NH_3-N$, phenol and ABS which caused the problems in drinking water treatment. Also, the treatabilities on humic acid were examined in the continuous flow type reactors. The removal efficiencies of humic acid, $NH_3-N$, phenol and ABS in the biodegradable experiments for 5 days were 20.1%, 73.4%, 91.7% and 97.5%, respectively. In the isothermal adsorption test of refractories on activated carbon to be used as a media in the continuous flow type reactors, ABS and phenol are adsorbed easily, but humic acid and $NH_3-N$ are difficult to be done. The removal efficiencies of humic acid in granular activated carbon(GAC) reactor were about 7-8% higher than in biological activated carbon(BAC) reactor. The removal efficiencies of humic acid in biological fluidized bed(BFB) reactor were about 30% in GAC media, but were almost zero in sea sand media.

• Journal of environmental and Sanitary engineering
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• v.12 no.1
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• pp.69-75
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• 1997

Biological drinking water treatment is widely used in Europe for the removal of ammonia nitrogen and organics. During the last 16 years, the deterioration of the quality of surface waters used to produce drinking water has resulted in the widespread use of ozone-biological treatment in Korea. This study were conducted to determine the effect of media weight and preozonation on the biodegradability enhancement in biological fluidized bed(BFB) using Han river water. When the carbon weight was increased, $NH_{3}-N$ and DOC removal increased, but turbidity and SS removal decreased. To remove turbidity and SS, the bed depth in 40% expansion rate/total bed depth was very important. Preozonation of raw water was not effective in $NH_{3}-N$, but increased in biodegradable organic fraction about 10-30% with 0.425-0.85 mg $O_{3}/mg$ DOC.

• Journal of Environmental Science International
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• v.14 no.3
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• pp.359-366
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• 2005

Starch was crosslinked with epichlorohydrin. Crosslinked starch-filled waterborne acrylate (CSWAC) films were prepared by blending this crosslinked starch with waterborne acrylate. The thermal and mechanical properties of these films were investigated by thermogravimetric analysis (TGA), tensile strength and elongation test. The biodegradability was also studied by determination of reduced sugar products after enzymatic hydrolysis and the surface morphology was investigated by scanning electron microscopy (SEM). The CSW AC film showed significantly higher tensile strength and elongation than those of starch-filled waterbonre acrylate (SWAC). The biodegradability of this film was higher than that of native starch-filled acrylate film, and was increased by the addition of crosslinked starch to the acrylate film.

• Journal of the Korean Applied Science and Technology
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• v.25 no.4
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• pp.429-437
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• 2008

The p-dioxanone can be used to make a variety of commercially useful products particularly where biodegradability is desired, such as fibers, sutures, molded articles, containers, medical devices and surgical clips, film and compostable trash bags. The mole fraction solubility of p-dioxanone in various solvents such as acetone, ethylacetate, tetrahydrofuran, methanol, ethanol, 1-propanol, 1-butanol and 1-pentanol were measured over the temperature range from 263.05 K to 288.45 K. The solubility of p-dioxanone increases with increasing polarity of the solvents.

• The Korean Journal of Community Living Science
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• v.17 no.2
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• pp.105-112
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• 2006

The biodegradability test of bulking agents in feces composting process is conducted to increase the management efficiency for environment-friendly rural toilet developed by National Rural Resource Institute in 2001. In the case study through references and field study, ash, fallen leaves, and wood chips are commonly used in the ecological toilet. Extension officers and farmers prefer rice straw, fallen leaves, and chaff among the rural resources as a bulking agents in the aspect of getting and storage as the result of questionnaire survey. As the result of biodegradability test including the temperature change, $CO_2$ gas production, and C/N ratio change of composting pile under the condition of aerobic composting apparatus, rice straw and chaff are good bulking agents for environment-friendly rural toilet. It is recommended that easy getting materials among the above mentioned materials are used for bulking agents as the region and season in environment-friendly rural toilet.

• Journal of environmental and Sanitary engineering
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• v.12 no.2
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• pp.29-35
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• 1997

Phenol, often discharged from petroleum and fine chemical industries is potential carcinogen and was classified into priority pollutant by EPA in USA. It causes serious environmental and health problem if discharged to the environment such as soil or aquifer. The removal efficiency of phenol and COD using Fenton treatment(Hydrogen Peroxide and Ferrous Sulfate) was observed and biodegradability (BOD$_{5}$/COD$_{cr}$) of reaction products were also examined. When 50 mg/l of phenol was treated by Fenton's Reagent(50 mg/l of hydrogen peroxide and 900 mg/l of ferrous sulfate), the removal efficiency of phenol and COD was 100% and 80% respectively in 10 minutes, which suggested this method can be used as actual phenol removal process. The initial biodegradability of 500 mg/l phenol solution was 0.7 but decreased as hydrogen peroxide was increased.