• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.236-244
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• 2022

BACKGROUND: Liquid fertilizers can provide nutrients to crops effectively and quickly. Amino acid liquid fertilizers produced by decomposing the residues of rendered livestock carcasses are expected to be effective in improving the productivity and quality of crops. METHODS AND RESULTS: The treatment conditions for maize cultivation were control (Cn), inorganic fertilizer (IF), inorganic fertilizer and rendering residue liquid fertilizer (IF+RALF), compost (CP), compost and rendering residue liquid fertilizer (CP+RALF). Crop productivity, sugar content, and nutrient uptake were investigated after maize harvest in the field applied with liquid fertilizers. Maize yields ranged from 87.6-158 g/plant, and the yield increased by 7.9% and 12.9% in IF+RALF IF+RALF and CP+RALF than in IF and CP, respectively. The maize sugar content increased in the range of 0.1-0.5 brix % by rendering residue liquid fertilizer (RALF) fertilization, and the sugar content was the highest in CP+RALF. There was no significant change in soil chemical properties of the soil due to liquid fertilizer treatment. CONCLUSION(S): RALF increased yield and sugar content in maize cultivation, and fertilization with organic fertilizers was more effective for maize cultivation than inorganic fertilizers. Residues of rendered livestock carcass can be recycled as amino acid fertilizers, which can be effectively used for crop production and quality improvement.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.85.2-85.2
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• 2010

There is widespread effort to develop polymer membranes in place of Nafion for high temperature polymer electrolyte membrane fuel cell(PEMFC). In our study, SiO2 membranes are arranged by electrospinning method. For impregnation solution, the modified sulfonated poly(ether ether ketone)(SPEEK) polymer is prepared from sulfonation, sulfochlorination, partial reduction and lithiation reaction. The modified polymer is cross-linked with 1,4-diiodobetane in NMP solvent and then blended with Heteropoly acid(HPA). The characterization of membranes is confimed by FT-IR, Thermogravimetry(TGA), water uptake test and single cell performance test for PEMFC, etc. The composite membrane shows satisfactory thermal and mechanical properties. Beside, The membrane exhibits good ion exchange capacity and high proton conductivity. As a result, The composite membrane is promising as an alternative membrane in high temperature PEMFC.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.391-398
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• 1999

A methylotrophic actinomycetes strain MO-16, which produce the antimicrobial compound, was isolated from soil and supposed as Amycolatopsis sp. based on taxonomic studies. The cell-free extract of methanol-grown strain MO-16 showed dehydrogenase activity for methanol and formaldehyde when various electron acceptors were added for oxidation. On the other hand, methanol did not affect the production of antimicrobial compounds, and organic nitrogen sources such as corn steep liquor and peptone were better than inorganic nitrogen sources. These compounds showed broad antimicrobial spectrum to the tested strains such as bacteria and yeast. The antimicrobial comounds were very stable under heat(121$^{\circ}C$), acid(pH2.0), alkali(pH11.0) treatments. These compounds were isolated by ethylacetate extract, silica gel column chromatography and reverse phase HPLC. Two compounds(peak 1 and 2) were detected as antimicrobial compounds through the HPLC analysis. The peak 2 was purified as a single compound and revealed a 98% purity.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.10a
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• pp.152-152
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• 2009

유기태양전지 Solvent인 1-2-Dichlorobenzene(DCB)에 1-Bromonaphtalene(BN)을 첨가하여 Air분위기에서 ZnO film을 이용한 유/무기 복합 태양전지를 만들었다. 셀의 구조는 ITO/ZnO nanofilm/Poly(3-hexylthiophene(P3HT):[6,6]-Phenyl C60-Butyric acid methyl ester(PCBM)/PEDOT:PSS/Ag로 제작했다. 두께 70nm ZnO film은 전기화학적 방법으로 ITO위에 전착하였다. AM1.5조건에서 Solar simulator로 측정한 결과 BN을 첨가한 셀에서 Jsc값이 증가되었다. Jsc값의 증가는 BN이 결정화를 향상시켜 효율이 증가됨을 확인하였다.

• Bulletin of the Korean Chemical Society
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• v.22 no.12
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• pp.1366-1370
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• 2001

Thin films of the SiO2-TiO2-PDMS composite material have been prepared by the sol-gel dip coating method. Acid catalyzed solutions of tetraethoxy silane (TEOS) and polydimethyl siloxane (PDMS) mixed with titanium isopropoxide Ti(OiPr) were used as precursors. The optical and structural properties of the organically modified 70SiO2-30TiO2 composite films have been investigated with Fourier Transform Infrared Spectroscopy (FT-IR), UV-Visible Spectroscopy (UV-Vis), Differential Thermal Analysis (DTA) and prism coupling technique. The films coated on the soda-lime-silicate glass exhibit 450-750 nm thickness, 1.56-1.68 refractive index and 88-94% transmittance depending on the experimental parameters such as amount of PDMS, thermal treatment and heating rate. The optical loss of prepared composite film was measured to be about 0.34 dB/cm.

• Safety and Health at Work
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• v.2 no.3
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• pp.229-235
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• 2011

Objectives: In this study, we summarized the External Quality Assessment Scheme (EQAS) for the biological monitoring of occupational exposure to toxic chemicals which started in 1995 and continued until a $31^{st}$ round robin in the spring of 2010. The program was performed twice per year until 2009, and this was changed to once a year since 2010. The objective of the program is to ensure the reliability of the data related to biological monitoring from analytical laboratories. Methods: One hundred and eighteen laboratories participated in the $31^{st}$ round robin. The program offers 5 items for inorganic analysis: lead in blood, cadmium in blood, manganese in blood, cadmium in urine, and mercury in urine. It also offers 10 items for organic analysis, including hippuric acid, methylhippuric acid, mandelic acid, phenylglyoxylic acid, N-methylformamide, N-methylacetamide, trichloroacetic acid, total trichloro-compounds, trans,trans-muconic acid, and 2,5-hexanedione in urine. Target values were determined by statistical analysis using consensus values. All the data, such as chromatograms and calibration curves, were reviewed by the committee. Results: The proficiency rate was below 70% prior to the first round robin and improved to over 90% for common items, such as PbB and HA, while those for other items still remained in the range of 60-90% and need to be improved up to 90%. Conclusion: The EQAS has taken a primary role in improving the reliability of analytical data. A total quality assurance scheme is suggested, including the validation of technical documentation for the whole analytical procedure.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.397-402
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• 1989

A new extracellular biopolymer was produced by Methylobacterium organophilum from methanol as a sole carbon and energy source. The purified biopolymer was found to have a high molecular weight of about 4-5$\times$10$^6$ dalton and contained 66% (w/w) of carbohydrate but no polyhydro xybutyrate. Other organic constituents were consisted of protein, pyruvic acid, uronic acid, and acetic acid, whereas content of inorganic ash was 22%. Based on the chemical analysis of the biopolymer by TLC method, the polymer was consisted of glucose, galactose, and mannose with an approximate molar ratio of 2:3:2. The biopolymer solution showed a characteristics of pseudoplastic non-Newtonian fluid. The viscosity of the 1%-biopolymer solution was found to be 18,000 cp at a shear rate, 1 sec$^{-1}$, which was almost 10 times higher than that of a commercial xanthan gum.

• ALGAE
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• v.32 no.3
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• pp.245-259
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• 2017

We report on the culture growth and stress-induced secondary carotenogenesis in a biotechnologically promising but largely unexplored chlorophyte Coelastrella rubescens strain Vinatzer/Innsbruck V 195. Changes in the cell morphometry, biomass accumulation, its carotenoid and fatty acid profiles were followed in the cultures supplemented with either inorganic ($CO_2$) or organic (sodium acetate) carbon on the background of low-pH stress. Collectively, the results of the study characterize C. rubescens as a biotechnologically promising, potentially double-purpose organism. It produces several secondary keto-carotenoids with a considerable proportion of astaxanthin and canthaxanthin. At the same time, the cell lipid fatty acid profile of this microalga is suitable for obtaining a high-quality biodiesel complying with the strictest EN14214 European standard.

• Journal of Soil and Groundwater Environment
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• v.12 no.2
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• pp.55-64
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• 2007

An analytical method using ion-exchange chromatography was developed for simultaneous quantification of low-molecularweight organic acids ($C_1-C_6$ aliphatic carboxylic acids) and inorganic anions, and then applied to the assessment of ground water contaminated by leachates from a municipal solid waste landfill. Peak interferences of halide ions to organic acids were removed by pretreatment of water samples with Ag-containing cartridges. This method allowed accurate detection of low-molecular weight organic acids (i.e., formate, acetate, propionate, pyruvate, succinate, and oxalateas) low as 0.5 mg/L with a linear dynamic range up to 20 mg/L within 11 min run time along with typical inorganic anions. High level of pyruvate and low level of formate and acetate were detected in groundwater and landfill leachates using the analytical method. Pyruvate concentration in groundwater showed a significant correlation with concentrations of $Cl^-$ and $HCO_3^-$, and pyruvate levels decreased along the downgradient from the landfill, indicating the sources of pyruvate are landfill leachate.

• Journal of Mushroom
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• v.20 no.4
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• pp.263-269
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• 2022

This study investigated the culture characteristics of Cryptoporus volvatus, whichis grow naturally in Korea, to determine the suitable environmental conditions for its cultivation. The physiological characteristics of the mycelia were assessed according to the cultivation conditions, to determine the optimal conditions for artificial cultivation. The visual characteristics of the hyphae of Cryptoporus volvatus KACC52303 included an irregular and uneven surface and a fuzzy or cotton-like texture. Under the microscope, its microstructure showed pre-chlamydospore formation, but no clamps were seen. The appropriate culture temperature was found to be a medium/high temperature of approximately 25-30℃, and the optimal pH was found to have a wide range from weakly acidic (pH 4) to neutral (pH 7). In the optimal nutrient source experiment, hyphal growth was shown to be fair in a mixed medium with 2.5% dextrin as the carbon source and 0.1% yeast extract as the organic nitrogen source. Among the various amino acids, organic acids, and inorganic salts tested, the fastest hyphal growth was observed in the presence of leucine, acetic acid or gluconic acid, and KCl or KH₂PO₄, respectively. The column test showed that the best mycelial growth occurred in a mixed medium of 80% pine sawdust, 10% rice bran, and 10% corncob sawdust.