• Journal of Biomedical Engineering Research
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• v.9 no.2
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• pp.225-232
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• 1988

Poly (L- lactic acid-co-glycine-L-lactic acid) and Poly (L-lactic acid-co-glycine-L- methyl lactic acid ) have been prepared by ring opening polymerization. The monomer 6, 6-dimethyl morpho-line-2, 5-dione was synthesized by the bromoisobutylation of 2-bromoisobutyryl bromide with glycin e. L-lactide, 6-methyl morpholine-2, 5-diode. and 6, 6-dimethyl morpholine-2, 5-diode have been used as starting materials for polydepsipeptides. The synthesized monomers and copolymers have been identified by NMR and FT-lR spa- ctrophotometer. The thermal propert ies and glass transition temperature(Tg) of the copolymers have been measured by differential scanning calorimetry. The Tg values of poly(L-lactic acid co-glycine-L-lactic acid) system are increased from $53^{\circ}C\; to\; 107^{\circ}C$ with increasing the mole fraction of 6-methyl morpholine-2, 5-diode. And the Tg values of poly(L-lactic acid co-glycine-L-methyl lactic acid) system are increased from $53^{\circ}C\;to\;138^{\circ}C$ with increasing the mole fraction of 6. 6-dimethyl morpholine-2, 5-diode The thermal stability of poly (L-lactic acid-co-glycine-L-methyl lactic acid) is slightly greta text than that of poly(L-lactic acid-co-glycine-L-lactic acid) due to the methyl group.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.1-3
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• 2003

The fused lumbar vertebrae (L) of the female Cheju native horse were observed macroscopically. The 5th L and 6th L were partially fused. They were composed of four parts between the spinous process of the 5th L and 6th L, left and right transverse process of the 5th L and 6th L, caudal articular process of the 5th L and cranial articular process of the 6th L, and fossa of vertebra of the 5th L and head of vertebra of the 6th L. The dorsal lumbar foramen and ventral lumbar foramen were formed each at left and right of medial parts in the fused transverse processes of the 5th and 6th lumbar vertebrae.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2509-2513
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• 2010

In order to increase protease stability of a novel Trp-rich model antimicrobial peptide, $K_6L_2W_3$ (KLWKKWKKWLK-$NH_2$)and investigate the effect of L-amino acid to peptoid residue conversion on biological functions, we synthesized its antimicrobial peptoid, $k_6l_2w_3$. Peptoid $k_6l_2w_3$ had similar bacterial selectivity compared to peptide $k_66L_2W_3$. The bactericidal rate of $k_6l_2w_3$ was somewhat slower than that of $K_6L_2W_3$. Peptoid $k_6l_2w_3$ exhibited very little dye leakage from bacterial outer-membrane mimicking PE/PG liposomes, as observed in $K_6L_2W_3$, indicating that the major target site of $K_6L_2W_3$ and $k_6l_2w_3$ may be not the cell membrane but the cytoplasm of bacteria. Trypsin treatment of $K_6L_2W_3$ completely abolished antimicrobial activities against Escherichia coli and Staphylococcus aureus. In contrast, the antimicrobial activity of $k_6l_2w_3$ was completely preserved after trypsin treatment. Taken together, our results suggested that antimicrobial peptoid $k_6l_2w_3$ can potentially serves as a promising therapeutic agent for the treatment of microbial infection.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.45-52
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• 2020

We examined the dyeability and antimicrobial activity of silks dyed singly with Sophora japonica L., Curcuma longa L., combination-dyed with Polygonum tinctorium L. and Sophora japonica L., and with Polygonum tinctorium L. and Curcuma longa L.. The color of silk dyed singly with Sophora japonica L., Curcuma longa L. was Yellow with Hue of 5.0Y and 0.6Y, respectively. Two types of combination-dyed silk were Blue Green with 2.6BG and 1.5BG, respectively. In the case of dry Cleaning fastness and rub fastness, all four types of dyed silk was good, achieving grade 4~5. The antimicrobial activity of Staphylococcus aureus of silk dyed with Sophora japonica L. extract showed excellent antibacterial activity of 99.5% and the other three types of dyed silk of 99.9%. In addition, in antibacterial activity against Klebsiella pneumonia, silk dyed with Sophora japonica L. extract showed 99.6%, and the other three types of dyed silk exhibited excellent antibacterial properties of 99.9%.

• Bulletin of the Korean Chemical Society
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• v.11 no.3
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• pp.206-208
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• 1990

Cu(II) hexaazamacrotricyclic complexes $[Cu(L)](ClO_4)_2$ and $[(Cu(L)Cl]ClO_4$, where L = 1,3,6,9,11,14-hexaazatricyclo$[12.2.1.1^{6,9}]octadecane(L_1)$ or 1,3,6,10,12,15-hexaazatricyclo$[13.3.1.1^{6,10}]eicosane(L_2)$, have been prepared by the simple template condensation reactions of triamines, diethylenetriamine for $L_1$, and N-(2-aminoethyl)-1,3-propanediamine for $L_2$, with formaldehyde in the presence of $Cu(OAc)_2\;or\;CuCl_2$. The Cu(II) complexes of $L_1$ contain two 1,3-diazacyclopentane ring moieties and those of $L_2$ contain two 1,3-diazacyclohexane ring moieties that are fused to the 14-membered macrocyclic framework. Spectra indicate that complexes $[Cu(L)](ClO_4)_2\;and\;[Cu(L)Cl]ClO_4$ have square-planar and square-pyramidal chromophores, respectively. square-planar $[Cu(L)](ClO_4)_2$ are remarkably stable against ligand dissociation in acidic aqueous solutions. Square-pyramidal $[Cu(L)Cl]ClO_4$ complexes dissociate their axial Cl-ligands easily in aqueous solutions to form $[Cu(L)H_2O]^{2+}$ species. Infrared and UV/vis absorption spectra of the Cu(II) complexes reveal that Cu-N interactions and the ligand field strengths are significantly weaker in the complexes of $L_2$ than in the complexes of $L_1$.

• Microbiology and Biotechnology Letters
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• v.30 no.1
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• pp.98-102
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• 2002

Lignocellulosic wastes available in abundance can be excellent substrates for the production of cellulase. Different types of substrates and various pretreatments were used to improve the production of cellulase. The steam-exploded wood chip gave the highest activities of FPase (0.84 IU/mL) and CMCase (6.5 IU/mL) in the shake-flask culture. In 30 L bioreactor the steam-exploded wood chip and residue after saccharification gave the FPase activity (0.72 IU/mL) and the CMCase activity (6.3 IU/mL), respectively, similar those obtained in lactose.

• Journal of Korean Society of Forest Science
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• v.102 no.4
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• pp.571-577
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• 2013

This study was carried out to establish the construction guidelines of soil erosion control structures for a restoration of mountain stream with analysis of water quality around constructed soil erosion control structures in mountain streams. Water pH of the Uidong valleys in Bukhansan (Mt.) was similar between the constructed soil erosion control structures of lower stream areas [pH 6.53(6.25~6.82)] and the non-constructed areas of upper stream areas [pH 6.32(5.73~6.90)]. Mean concentration of dissolved oxygen was also similar between the constructed soil erosion control structures of lower steam areas [10.2 mg/L(9.9~10.4 mg/L)] and the non-constructed areas of upper stream areas [10.3 mg/L (9.6~10.6 mg/L)]. Mean electric conductivity was similar between the lower [$63.9{\mu}S/cm$ ($32.6{\sim}120.4{\mu}S/cm$)]a nd the upper stream areas [$62.2{\mu}S/cm$ ($40.3{\sim}89.5{\mu}S/cm$)]. Mean concentration of anions was also similar between the lower [15.94 mg/L (3.43~7.98 mg/L)] and the upper stream areas [14.51 mg/L (2.56~4.29 mg/L)]. Water pH of the Honggei valleys in Sancheong-gun was similar between the lower [pH 6.86(6.50~7.10)] and the upper stream areas [pH 6.89(6.61~7.12)]. Mean concentration of dissolved oxygen was also similar between the lower [11.9 mg/L(11.5~12.3 mg/L)] and the upper stream areas [12.2 mg/L (11.6~12.6 mg/L)]. Mean electric conductivity was similar between the lower [$633.4{\mu}S/cm$ ($31.6{\sim}34.6{\mu}S/cm$)] and the upper stream areas [$32.7{\mu}S/cm$ ($31.4{\sim}34.3{\mu}S/cm$)]. Mean concentration of anion was also similar to both stream areas [1.0 mg/L (0.1~2.2 mg/L)]. Water quality in the Uidong and the Honggei valleys was not significantly different between the constructed soil erosion control structures of lower stream areas and the non-constructed areas of upper stream areas. It will be needed to study the time-series analysis of water quality before and after the construction of soil erosion control structure the restoration of mountain streams because the water quality in mountain streams could be affected during the construction processes of structures.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.403-403
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• 2015

본 연구에서는 강우시 도로지역에서 발생하는 비점오염물질 유출 및 수질특성을 살펴보고자 도로지역(국도 46호선)을 대상으로 총 16회의 강우사상에 대해 분석하였다. 모니터링 기간(2014년 5월~9월)동안 연구대상지역에는 3.2~80.3 mm의 강우가 발생하였으며, 강우강도는 0.39~11.29 mm/hr의 범위로 나타났다. 선행무강우일수는 0.3~20.1일이며, 총 유출량은 0.1~6.8 ㎥, 유출율은 0.24~0.85(평균 0.6)의 범위로 나타났다. 강우 모니터링 결과, 유량가중평균농도(Event Mean Concentration, EMC)는 TOC 4.9~56.2 mg/L(평균 18.0 mg/L), BOD 3.1~21.5 mg/L(평균 7.5 mg/L), COD 6.7~58.6 mg/L(평균 23.6 mg/L), SS 2.1~281.9 mg/L(평균 59.4 mg/L), T-N 1.07~13.46 mg/L(평균 4.89 mg/L) 그리고 T-P 0.065~0.680 mg/L(평균 0.23 mg/L)의 범위로 나타났으며, 강우계급별로 살펴보면 0~10 mm일 때 BOD 9.3 mg/L, COD 30.5 mg/L, SS 84.1 mg/L, T-N 5.42 mg/L, T-P 0.27 mg/L로, 10~30 mm일 때 BOD 6.6 mg/L, COD 22.0 mg/L, SS 29.0 mg/L, T-N 4.9 mg/L, T-P 0.20 mg/L로, 50 mm 이상의 강우에서는 BOD 3.6 mg/L, COD 7.1 mg/L, SS 46.4 mg/L, T-N 3.42 mg/L, T-P 0.10 mg/L로 강우계급별 EMC는 대부분 수질항목에 있어 10 mm 이하 계급의 평균 EMC가 높은 수준으로 나타났다. 그리고 각 강우사상에 대한 단위면적당 오염부하는 TOC 0.06~3.5 kg/ha, $BOD_5$ 0.03~1.6 kg/ha, CODMn 0.09~4.74 kg/ha, SS 0.09~35.99 kg/ha, T-N 0.012~2.600 kg/ha, T-P 0.001~0.062 kg/ha의 범위로 산정되었다. 도로지역은 불투수층 면적비율이 높아 누적강우량 10 mm 이하에서도 유출이 발생하는 것으로 분석되었으며, 작은 강우에도 초기유출이 발생하고 유출되는 오염물질 농도가 높은 경향을 나타내었다.

• Microbiology and Biotechnology Letters
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• v.37 no.2
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• pp.176-182
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• 2009

Hydrogen producing bacterium, strain MeL 6-2 was isolated from the sludge of the factory areas in Anyang through the acclimation in basal salt medium (BSM) supplemented with 10 g/L of sucrose. Isolated strain MeL 6-2 was a facultative anaerobe which could grow in both aerobic and anaerobic environments. An aerobically grown pure culture isolated from enriched culture was analyzed by 16S rDNA sequencing and identified as Rhodopseudomonas sp. MeL 6-2. Effects of the concentrations of glucose and sucrose on the hydrogen production rate and the hydrogen production yield were investigated. When glucose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow without lag phase. An increased glucose concentration increased the specific hydrogen production rate linearly to $4.2\;mmol-H_2{\cdot}L^{-1}{\cdot}h^{-1}$ at 10 g/L, and $60\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$, but decreased slightly as the concentration increased to 12 g/L. The hydrogen production yield was maintained over a range from 2.6 to $3.1\;mol-H_2{\cdot}mol-glucose^{-1}$. When sucrose in the range of 1~12 g/L was supplemented to the BSM, strain MeL 6-2 could grow after ten hours. An increased sucrose concentration increased the specific hydrogen production rate and the hydrogen production yield to $163\;mmol-H_2{\cdot}mg-DCW^{-1}{\cdot}h^{-1}$ and to $4.5\;mol-H_2{\cdot}mol-sucrose^{-1}$, respectively.

• Journal of the Korea Organic Resources Recycling Association
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• v.31 no.4
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• pp.41-49
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• 2023

This study examined the effect of input substrate concentration on hydrogen production of microbial electrolysis cells. To compare the performance of MEC according to the input substrate concentration, six laboratory-scale MEC reactors were operated by sequentially increasing the input substrate concentration from 2 g/L of sodium acetate, to 4 g/L, and 6 g/L. The current density, hydrogen production, and SCOD removal rate were analyzed, and energy efficiency and cathodic hydrogen recovery were calculated to compare the performance of MEC. The maximum volumetric current density was obtained at 4 g/L condition (76.3 A/m³) and it decreased to 19.0 A/m³, when the input concentration was increased to 6 g/L, which was a 75% decrease compared to the 4 g/L input condition. Maximum hydrogen production was obtained also at 4 g/L condition (47.3 ± 16.8 mL), but maximum hydrogen yield was obtained at 2 g/L input condition (1.1 L H₂/g COD_in). Energy efficiencies were also highest in 2 g/L condition; the lowest result was observed at 6 g/L condition. Maximum electrical energy efficiency was 76.4%, and the maximum overall energy efficiency was 39.7% at 2 g/L condition. However, when the substrate concentration increased to 6 g/L, the performance was drastically decreased. Cathodic hydrogen recovery also showed a similar tendency with energy efficiency, with the lowest concentration condition showing the best performance. It can be concluded that operating at low input substrate concentration might be better when considering not only hydrogen yield but also energy efficiency.