• Journal of the Korean Wood Science and Technology
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• v.21 no.1
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• pp.59-64
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• 1993

The purpose of this study is to investigate the preparation of the carboxymethylcellulose from recycled fiber, especially on the reactivity of carboxymethylation. Using a deinked pulp and a dissolving pulp. Green's method is adapted to the carboxymethylation. We conformed that the carboxymethyl group is led for recycled fiber by FT-IR analysis. The recycled fiber is more reactive than the dissolving pulp because the recycled fiber had been defiberated and pretreated with alkali. It suggests that deinking process is in accordance with pretreatment of CMC process. Therefore, it may be possible to prepare CMC from the recylced fiber economically.

• Korean Journal of Mathematics
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• v.25 no.4
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• pp.555-561
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• 2017

We show that a closed curve invariant under inversions with respect to two intersecting circles intersecting at angle of an irrational multiple of $2{\pi}$ is a circle. This generalizes the well known fact that a closed curve symmetric about two lines intersecting at angle of an irrational multiple of $2{\pi}$ is a circle. We use the result to give a different proof of that a compact embedded cmc surface in ${\mathbb{R}}^3$ is a sphere. Finally we show that a closed embedded cmc surface which is invariant under the spherical reflections about two spheres, which intersect at an angle that is an irrational multiple of $2{\pi}$, is a sphere.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.10a
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• pp.235-237
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• 2009

변전자동화시스템이 IEC 61850 규격도입 이후 통신에 대한 적합성 시험과 함께 보호계전기의 보호 및 제어기능에 대한 시험도 통신과 결부되어 자동화하려는 추세에 있다. 기존에 변전소에 적용된 디지털 보호계전기는 IEC 61850 통신서비스와 접목되어 IED(Intelligent Electronic Device)로 불려진다. 기존의 보호계전기와 달리 IED의 경우 변전자동화시스템으로 통합구현되기 때문에 IED 단위시험 보다는 시스템 수준의 성능시험을 요구하게 된다. 따라서 CMC 256 전용프로그램을 가지고는 변전자동화시스템의 성능시험을 완벽하게 다루게 어렵게 때문에 사용자가 CMC 256 장비를 자유롭게 다룰 수 있는 환경개발을 필요로 한다. 본 논문에서는 CMC 256 장비의 운용을 사용자 정의로 구현할 수 있는 CM Engine을 소개하고 실제 구현사례를 통해 변전자동화시스템의 성능시험을 위한 기반 자료를 다루고자 한다.

• Journal of Environmental Health Sciences
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• v.24 no.2
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• pp.104-109
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• 1998

The objective of this study was to examine the effect of polymer coating on the initial microorganism attachment and the biofilm growth. Such as nonion(polyacrylamine), anion(CMC-Na) and cation polymer coagulant(chitosan and PEI) were used for coating material of the support carrier(acryl plate). When polymer coagulant was coated with 5, 10, 20, 35, 50, 100 and 200 mg/l on the surface of acryl plate, initial microorganism attachment increased and optimum concentration for the attachment was 35 mg/l. Biofilm growth experiments were conducted with the substrate loading of 12.7gSCOD/$m^2\cdot$ day using RBC. The polymer coagulants such as CMC-Na, polyacrylamide, PEI and chitosan coating on the acryl plate facilitated the biofilm growth of microorganisms. Until the biofilm dry weight grows up to 0. 0038g/cm$^2$, biofilm growth on the plate coated with cation polymer like chitosan was better than that on the coated plate of nonion(polyacrylamine), anion(CMC-Na) polymer coagulant.

• Proceedings of the Membrane Society of Korea Conference
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• 1994.03a
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• pp.1-21
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• 1994

There are growing needs to produce relatively high purity (99.0% or higher) oxygen at low cost. For small scale production, both pressure swing adsorption (PSA) and membrane process are competitve and less expensive or more convient than well known crygenic fractionation technology. A continuous membrane colume (CMC) combined with a PSA oxygen generator can be employed to produce high purity oxygen continuosly. The oxygen-enriched gas generated by a PSA unit, with a concentration of 93-94%, is fed to the CMC that consists of three modules of poly(imide) hollow fibers. Several experiments were conducted by varying parameters, such feed flow rate, transmenbrane pressure drop, stage cut, and feed location in order to obtain a high oxygen concentration above 99.0%. A two-series unit mode was also employed with CMC operation to optimize the given membrane area.

• Bulletin of the Korean Chemical Society
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• v.27 no.4
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• pp.529-534
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• 2006

Chemical modification of the S. cerevisiae farnesyl protein transferase (FPT) with CMC, phenylglyoxal and DEPC resulted in enzyme inactivation, depending upon the reagent concentration. The peptide substrate GST-PEP-I, a GST-fused undecapeptide mimicking the C-terminus of $p21^{Ki-ras}$, protected the enzyme against inactivation by CMC which is specific to either aspartate or glutamate, while the other substrate farnesyl pyrophosphate (FPP) showed protection against phenylglyoxal which is the specific modifier of arginine residues, dependent on the substrate concentrations. Neither of the two substrates protected the enzyme against histidine inactivation by DEPC. It is suggested that there is at least one aspartate or glutamate residue at the peptide substrate binding site, and that at least one arginine residue is located at the binding site of FPP. There also seems to be at least one histidine residue which is critical for enzymic activity and is exposed toward the bulk solution, excluded from the substrate binding sites.

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1449-1454
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• 2003

A new equation has been derived on the basis of ${\delta}G^o$ = -RT lnK, linear behavior of the enthalpy of micellization with temperature, and the Gibbs-Helmholtz relation. It describes correctly the dependence of critical micelle concentration $(X_{CMC})$ on temperature and has yielded excellent fitting results for various surfactant systems. The new equation results in the linear behavior of the entropy of micellization with temperature and accounts for the compensation phenomena observed for the micellization in aqueous solutions, along with the linear dependence of the enthalpy of micellization on temperature. These results imply that the new equation of $X_{CMC}(T)$ accounts for the temperature dependence of CMC correctly.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.4
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• pp.337-341
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• 2007

In this paper, we studied counter electrodes that carbon materials is used for dye-sensitized solar cells. Carbon electrodes characterized by changing of CMC wt. %. We investigated a porous structure of electrodes and a specific resistance of carbon electrodes for identification of electric conductivity. The specific resistance of carton electrodes increased by an increase of CMC wt. % and this result affected an efficiency of the cells.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.1-7
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• 2003

In this study, fiber mechanical pretreatment before refining was executed with the addition of papermaking addiditives to find synergistic effects on fiber property improvement. Three fiber furnishes (SwBKP, KOCC, and BCTMP), and five different additives (CMC, CPAM, PEO, NaOH, $Na_2O_2$) were used. It was confirmed again that fiber mechanical pretreatment using Hobart mixer was a special way to modify fiber properties, where fiber WRV (water retention value) increases without losing fiber length. For SwBKP, addition of small amount of CMC (0.2％ OD basis), and for KOCC, PEO (0.2％ OD basis) caused additional significant improvement of the fiber furnish properties, respectively. Other additives did not cause adverse effects on the mechanical pretreatment, or better. For BCTMP, NaOH addition followed by mechanical pretreatment caused more than 20％ improvement in tensile and tear strength simultaneously, compared to the control. The yellowing caused by the treatment of NaOH on BCTMP could be minimized by using $Na_2O_2$ without losing the positive effect of NaOH.

• Korean Journal of Microbiology
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• v.22 no.2
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• pp.97-101
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• 1984

To investigate the biodegradation pattern of rice straw, mainly composed of cellulose, hemicellulose and lignin components, by the isolate stran Bacillus subtilis $DO_4$, the change of cell population was observed on CMC (carboxymethyl cellulose), larch wood xylan and lignosulfonate as a carbon source respectively. Also, the transition pattern of enzyme activities of cellulase and xylanase and lignin contents was measured on rice straw and mixed substrate according to growth. The results in these experiments revealed that xylanase activity was first appeared and cellulase activity in the next, while lignin component was almost not changed through the culture period.