• Bulletin of the Korean Chemical Society
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• v.35 no.3
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• pp.715-720
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• 2014

A Cu(II) complex with an three nitrogens and one sulfur coordination environment was synthesized and characterized. Its redox potential was observed at 0.483 V vs. NHE, very similar to that of a Cu-containing fungal enzyme, galactose oxidase, which catalyzes the oxidation of alcohols to corresponding aldehydes with the concomitant reduction of molecular oxygen to water. The Cu(II) complex selectively oxidizes the benzylic alcohols using TEMPO/$O_2$ under mild reaction conditions to corresponding aldehydes without forming any over-oxidation product. Moreover, the catalyst can be recovered and reused multiple times for further oxidation reactions, thus minimizing the waste generation.

• Archives of Pharmacal Research
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• v.29 no.3
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• pp.195-198
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• 2006

Slavins A (1) and B (2), the new amyrin type triterpenes, have been isolated from the chloroform soluble fraction of Salvia santolinifolia and assigned structures on the basis of spectral studies including 2D NMR. Both the compounds displayed inhibitory potential against the enzyme butyrylcholinesterase.

• Journal of the Korean Chemical Society
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• v.14 no.2
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• pp.141-145
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• 1970

The reduction of Mo-thiocyanate (V) complex on dropping mercury electrode has been studied at ionic strength 0.6 with pH less than 2.3. D-C polarogram obtained from acidic solutions are reversible, diffusion controlled current. The electrode reaction of Mo-thiocyanate(V) may be represented as follows. $MoO(SCN)_3\;+\;2H^+\;+\;2e\;{\to}\;Mo(SCN)_2{^+}\;+\;H_2O\;+\;SCN^-$From this reaction, the half wave potential assumed to be $E_{1/2}\;=\;E_0'\;-\;0.059\;pH\;-\;0.03\;log{\;frac{[Mo(SCN)_2{^+}][SCN^-]}{[MoO(SCN)_3]}}$Considering the dissociation of this complex, however, it was estimated that the electrode reaction may be written by. $MoO^{+3}\;+\;3SCN^-\;+\;2H^+\;+\;2e\;{\to}\;Mo(SCN)_2{^+}\;+\;SCN^-\;+\;H_2O$.

• Journal of Microbiology and Biotechnology
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• v.14 no.2
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• pp.426-429
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• 2004

Eleven fungal strains previously isolated from the Mexican desert were evaluated for their capacity to use catechin as carbon source in submerged cultures. At 2 g/l of catechin, all strains grew better than the control strains, Aspergillus niger Aa-20. Aspergillus niger PSH and Penicillium commune EH2 degraded 79.33％ and 76.35％ with degradation rates of 0.0065 and 0.0074 g/l/h, respectively, when an initial catechin concentration of 3 g/l was used. Obtained results demonstrated the potential biotechnological capacity of these fungal strains to use condensed tannins as carbon source.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.20
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• pp.181-212
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• 2003

Many seafood processing and export companies are scattered in Pusan area. Most of them has experienced hardships, because of physical distribution and sanitary costs, rent costs and Non-tariff barriers. GamCheon One-Stop Seafood Export Complex (GOSEC) is considered as the project which is necessary to establish GamCheon port as the seafood trade hub of Northeast Asia. GOSEC is to build the processing and export complex for seafood export. It applies to small and medium seafood export company. This paper aims to examine the economic benefit which could be derived from the construction of GOSEC. It reviews the quantifiable benefits of companies which wants to move into GOSEC. It also shows the results of questionnaire carried out to find the characteristics of potential GOSEC tenants.

• Korean Journal of Plant Taxonomy
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• v.47 no.4
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• pp.304-307
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• 2017

We report somatic chromosome numbers for three species belonging to the Euphorbia pekinensis complex distributed in Far East Asia. In E. pekinensis populations distributed in Korea, 2n = 28 and 56 were found, while the Japanese native E. lasiocaula was also found at 2n = 28 and 56 and the Japanese endemic E. sinanensis was found at 2n = 20. Based on the number of chromosomes, E. lasiocaula distributed in Japan supports treatment as a variety of E. pekinensis rather than as a different species, while E. sinanensis should be recognized as a distinct species rather than as a variety of E. pekinensis. In the same populations of E. pekinensis and E. lasiocaula, diploid and tetraploid individuals were found, and the diversity of these chromosome numbers was consistent with the morphological diversity of these populations, suggesting the future evolutionary potential of this species.

• International Journal of Control, Automation, and Systems
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• v.6 no.1
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• pp.35-43
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• 2008

The control of underactuated mechanical system is very complex for the loss of its control inputs. The model of underactuated mechanical systems in a potential field is built with Lagrangian method and its structural properties are analyzed in detail. A genetic algorithm (GA)based stable control approach is proposed for the class of under actuated mechanical systems. The Lyapunov stability theory and system properties are utilized to guarantee the system stability to its equilibrium. The real-valued GA is used to adjust the controller parameters to improve the system performance. This approach is applied to the underactuated double-pendulum-type overhead crane and the simulation results illustrate the complex system dynamics and the validity of the proposed control algorithm.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.754-760
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• 1998

It was found that the adsorption of a cobalt(III) complex with a macrocyclic ligand, C-meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (hmc), was induced on a glassy carbon electrode by heavily oxidizing the electrode surface. Adsorption properties are discussed. The glassy carbon electrode with the adsorbed complex was employed to see the catalytic activities for the electro-reduction of O2. In the presence of oxygen, reduction of (hmc)Co3+ showed two cathodic waves in cyclic voltammetry. Compared to the edge plane graphite electrode at which two cathodic waves were also observed in a previous study, catalytic reduction of O2 occurred in the potential region of the first wave while it happened in the second wave region with the other electrode. A rotating disk electrode after the same treatment was employed to study the mechanism of the O2 reduction and two-electron reduction of O2 was observed. The difference from the previous results was explained by the different reactivity of the (hmc)CoOOH2+ intermediate, which is produced after the two electron reduction of (hmc)Co3+ in the presence of O2.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.417-422
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• 1998

The electrocatalytic reduction of molecular oxygen was investigated with a Co(II)-glyoxal bis(2-hydroxyanil) complex coated-glassy carbon (GC) electrode in aqueous media. The reduction of $O_2$ at the modified electrode was an irreversible and diffusion-controlled reaction. The complex coated-GC electrode demonstrated an excellent electrocatalytic effect for $O_2$ reduction in an acetate buffer solution of pH 3.2. The coated electrode made the $O_2$ reduction potential shift of 60-510 mV in a positive direction compared to the bare GC electrode depending on pH. The Co(II)-glyoxal bis(2-hydroxyanil) coated electrode converted about 51% of the $O_2$ to $H_2O_2$ via a two-electron reduction pathway, with the balance converted to H_2O$.

• BMB Reports
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• v.52 no.4
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• pp.227-238
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• 2019

GROWTH-REGULATING FACTORs (GRFs) are sequence-specific DNA-binding transcription factors that regulate various aspects of plant growth and development. GRF proteins interact with a transcription cofactor, GRF-INTERACTING FACTOR (GIF), to form a functional transcriptional complex. For its activities, the GRF-GIF duo requires the SWITCH2/SUCROSE NONFERMENTING2 chromatin remodeling complex. One of the most conspicuous roles of the duo is conferring the meristematic potential on the proliferative and formative cells during organogenesis. GRF expression is post-transcriptionally down-regulated by microRNA396 (miR396), thus constructing the GRF-GIF-miR396 module and fine-tuning the duo's action. Since the last comprehensive review articles were published over three years ago, many studies have added further insight into its action and elucidated new biological roles. The current review highlights recent advances in our understanding of how the GRF-GIF-miR396 module regulates plant growth and development. In addition, I revise the previous view on the evolutionary origin of the GRF gene family.