• Journal of Microbiology and Biotechnology
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• v.9 no.5
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• pp.646-649
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• 1999

A thermophilic bacterium producing D-stereospecific dipeptidase was isolated from Korean soil samples. The enzyme hydrolyzed the peptide bond between D-alanyl-D-alanine (D-Ala-D-Ala). The isolated bacterial strain was rod shaped, gram-positive, motile, and formed an endospore. Morphological and physiological characteristics suggested this microorganism a thermophilic Bacillus species, and was named as Bacillus sp. BCS-l. The production of D-stereospecific dipeptidase was growth-associated and optimal at $55^{\circ}C$. The enzyme was applied for the synthesis of D-amino acid-containing peptide, N-benzyloxycarbonyl-L-aspartyl-D-alanine benzyl ester (Z-L-Asp-D-AlaOBzl), as a model reaction. A thermodynamically controlled synthesis of Z-L-Asp-D-AlaOBzl was achieved in an organic solvent.

• Advances in nano research
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• v.6 no.1
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• pp.81-92
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• 2018

Biosynthesis of nanoparticles has acquired particular attention due to its economic feasibility, low toxicity and simplicity of the process. Extracellular synthesis of nanoparticles by bacteria and fungi has been stated to be brought about by enzymes and other reducing agents that may be secreted in the culture medium. The present study was carried out to determine the underlying mechanisms of extracellular silver nanoparticle synthesis by Pseudomonas hibiscicola isolated from the effluent of an electroplating industry in Mumbai. Synthesized nanoparticles were characterized by spectroscopy and electron microscopic techniques. Protein profiling studies were done using Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis (1D-SDS PAGE) and subjected to identification by Mass Spectrometry. Characterization studies revealed synthesis of 50 nm nanoparticles of well-defined morphology. Total protein content and SDS PAGE analysis revealed a reduction of total protein content in test (nanoparticles solution) samples when compared to controls (broth supernatant). 45.45% of the proteins involved in the process of nanoparticle synthesis were identified to be oxidoreductases and are thought to be involved in either reduction of metal ions or capping of synthesized nanoparticles.

• Journal of the Korean Ceramic Society
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• v.56 no.6
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• pp.541-548
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• 2019

Zirconia (ZrO₂) materials are widely used in a variety of energy systems and devices. When nanorod-shaped ZrO₂ is used as energy materials, ionic conductivity and mechanical strength can be improved compared to the characteristics of conventional spherical-shaped nanomaterials. In this study, we synthesized ZrO₂ nanorods and investigated the shape change of them depending on various synthesis conditions such as precursor concentration, synthesis temperature, synthesis period, and aging period. The obtained nanorods were casted into a membrane for alkaline water electrolysis system and subjected to basic performance evaluation for use as a separator. The structure and the shape of the nanorods were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the like.

• Transactions of the Korean hydrogen and new energy society
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• v.15 no.4
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• pp.283-290
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• 2004

The single-step process for conversion of syngas to DME give higher conversion than the syngas-to-methanol process. This arises because of a synergy among the three simultaneous reaction, methanol synthesis, methanol dehydration and water gas shift reaction, in the process. we would find the optimal condition of the process which these advantages. The optimal condition of DME synthesis reaction over a commercial $Cu/Zn/Al_2O_3$ catalyst and Hybrid catalyst in a fixed bed reactor. The syngas-to-dimethyl ether conversion was examined on various reaction condition (Temperature 473~553K, $H_2/CO$ ratio 1~3, Pressure 30'50atm, GHSV 1000~4000).

• Biomolecules & Therapeutics
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• v.16 no.1
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• pp.28-33
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• 2008

Atorvastatin calcium salt (1) was obtained through the preparation of lactone compound (8) from 2-((4R,6R)-6-(2-(2-(4-fluorophenyl)-5-isopropyl-3-phenyl-4-(phenylcarbamoyl)-1H-pyrrol-1-yl)-ethyl)-2-phenyl-1,3,2-dioxaborinan-4-yl)acetic acid tert-butyl ester (9) by hydrolysis in basic condition. Efficient hydrolysis of boronate compound 9 aimed at the viable synthesis for commercial production and purification of Atorvastatin calcium is reported. Detail studies of evaluation procedure are also reported.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1560-1563
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• 2001

An ability to utilize the substrates (acetate, glucose and lactate) in the lipid synthesis was measured in vitro with the adipose tissues of 4 locations (subcutaneous, SUBC; intramuscular, INTR; tail and kidney, KIDN) in 12 Hanwoo (Korean native cattle) steers (26 and 28 months of ages, mean body weight 638.6 kg). The rates of lipid synthesis from acetate were higher than those from glucose in SUBC and ITRA adipose tissues, respectively. In contrast, the rates of lipid synthesis from glucose were higher than those from acetate in the adipose tissues of tail and KIDN, respectively. Lactate utilization was lowest in all the locations while that of acetate or glucose had the different trends of utilization in the lipogenesis. The rate of lipid synthesis from acetate was highest in the SUBC adipose tissue but was lowest in the KIDN while that from glucose was also higher in the SUBC adipose tissue than in the other tissue locations. The rate of lipid synthesis from lactate, however, was highest in the tail adipose tissue among the locations.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.3
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• pp.11-18
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• 2013

Interest in copper nanoparticles has increased as an alternative for substituting silver nanoparticles because of its lower cost and less electromigration effect than silver. In this paper, the recent research trends and main results in wet-chemical synthesis of sub-100 nm Cu nanoparticles were summarized. The characteristics of synthesis were discussed with a classification such as modified polyol synthesis, modified hydrothermal synthesis, solvothermal synthesis, and the others, focussing on effects of capping agents, reductants, and pH. Information on the oxidation of synthesized copper nanoparticles were additionally commented.

• 한국가스학회:학술대회논문집
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• 2005.10a
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• pp.131-134
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• 2005

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.429-431
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• 1989

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.154.2-154.2
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• 2007