• Title/Summary/Keyword: cmc

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Effect of NaCl on the Mixed Micellar Properties of Sodium Dodecyl Sulfate(SDS) with Tetraethylene Glycol Monododecyl Ether(TGME) (Sodium Dodecyl Sulfate(SDS)와 Tetraethylene Glycol Monododecyl Ether(TGME)의 혼합미셀화에 미치는 NaCl의 효과)

  • Lee, Byung-Hwan
    • Journal of the Korean Chemical Society
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    • v.39 no.12
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    • pp.896-901
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    • 1995
  • The critical micelle concentrations(CMC$^*$) of the mixed surfactant systems of Sodium dodecyl sulfate(SDS) with Tetraethylene glycol monododecyl ether(TGME) in the aqueous solutions of NaCl at $25^{\circ}C$ were determined as a function of the overall mole fraction of $SDS(\alpha1)$ by the use of surface tension method. Various thermodynamic parameters for the micellization of SDS/TGME mixed surfactant systems were calculated and analyzed by means of the equations derived from the nonideal mixed micelle model, based on the pseudo-phase separation model.

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Isolation of Cellulolytic Microorganisms and their Physiological Characteristics (섬유소분해균의 분리 및 그의 생리학적 특성)

  • 홍순우;하영칠;민경희;이영하
    • Korean Journal of Microbiology
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    • v.14 no.1
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    • pp.17-24
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    • 1976
  • Celluloytic microorgnasims were isolated form the various sources and four of them were identified as Trichoderma roningi, Aspergillus niger, Penicillium chrysogenum, and Streptomyces sp. The induction of extracellular5 cellulase of these species in the liquid culture media containing carboxymethylcellulose (CMC) or Avicel as inducer showed that CMC was a better effective inducer for the production of CMCase(Cx cellulase component) as well as Avicelase(C$_{1}$ cellulase component) than Avicel. It is believed that certain hydrolysis products of cellulose(CMC) could serve as an inducer for an enzyme synthesis. In T. roningi, Asp. niger, and Strptomyces sp., the optimum temperature of CNCase on CMC-culture medium was 50.deg. but temperature around 40.deg.C was found to be optimum for the activities of CMCase prepared from P.ehrysogenum. The optimum temperature for Avicelase activitiles on Avicel-culture media of T. roningi and P. chrysogenum was $40{\circ}C$ whereas temperature $50{\circ}C$ was found to be optimum for Avicelase from A.niger and Streptomyces sp. The optimal activities of these CNCase and Avicelase prepared from. T. ronigi, Pen.chrysogenum and Streptomyces sp. were found similarly to be at pH's around 5.4 and 6.0 while pH 4.8 was optimum for the activities of CMCase and Avicelase from A.niger, indicating that A.niger in acidic media would yield an enzyme of high activity.

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Partially Carbonized Poly (Acrylic Acid) Grafted to Carboxymethyl Cellulose as an Advanced Binder for Si Anode in Li-ion Batteries

  • Cho, Hyunwoo;Kim, Kyungsu;Park, Cheol-Min;Jeong, Goojin
    • Journal of Electrochemical Science and Technology
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    • v.10 no.2
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    • pp.131-138
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    • 2019
  • To improve the performance of Si anodes in advanced Li-ion batteries, the design of the electrode plays a critical role, especially due to the large volumetric expansion in the Si anode during Li insertion. In our study, we used a simple fabrication method to prepare Si-based electrodes by grafting polyacrylic acid (PAA) to a carboxymethyl cellulose (CMC) binder (CMC-g-PAA). The procedure consists of first mixing nano-sized Si and the binders (CMC and PAA), and then coating the slurry on a Cu foil. The carbon network was formed via carbonization of the binders i.e., by a simple heat treatment of the electrode. The carbon network in the electrode is mechanically and electrically robust, which leads to higher electrical conductivity and better mechanical property. This explains its long cycle performance without the addition of a conducting agent (for example, carbon). Therefore, the partially carbonized CMC-g-PAA binder presented in this study represents a new feasible approach to produce Si anodes for use in advanced Li-ion batteries.

The Effects of Action Observation with Functional Electrical Stimulation on Corticomuscular Coherence

  • Kim, Ji Young;Ryu, Young Uk;Park, Jiwon
    • The Journal of Korean Physical Therapy
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    • v.32 no.6
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    • pp.365-371
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    • 2020
  • Objective: To investigate the action observation effects of functional electrical stimulation (FES) on the communication between motor cortex and muscle through corticomuscular coherence (CMC) analysis. Methods: Electroencephalogram (EEG) and electromyogram (EMG) of 27 healthy, nonathlete subjects were measured during action observation, FES, and action observation with FES, which lasted for 7sper session for 10 times. All trials were repeated for 30 times. Simultaneously measured EEG raw data and rectified EMG signals were used to calculate CMC. Only confidence limit values above 0.0306 were used for analysis. CMC was divided into three frequency domains, andthe grand average coherence and peak coherence were computed. Repeated ANOVA was performed to analyze the coherence value difference for each condition's frequency band. Results: CMC showed significant differences in peak coherence and average coherence between the conditions (p<0.05). Action observation application with FES in all frequency band showed the highest peak and average coherence value. Conclusions: The results of this study are assumed to be the combination of increased eccentric information transfer from the sensorymotor cortex by action observation and an increased in concentric sensory input from the peripheral by the FES, suggesting that these are reflecting the sensorimotor integration process.

Combination of Colony Formation and Congo Red Reaction for Detecting Intra- and Extra-Cellular Cellulolytic Activities (세포내외 섬유소 분해능 검출을 위한 Colony 형성과 Congo Red반응의 병용)

  • Lee, D.S.;Kim, H.K.;Pack, M.Y.
    • Microbiology and Biotechnology Letters
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    • v.12 no.4
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    • pp.305-309
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    • 1984
  • A selective medium which allows growth of only cellulolytic bacteria was developed. The medium composed of 0.5% carboxymethylcellulose (CMC), 0.005% yeast extract, minerals and agar. Colony formation on this medium indicates overall activities of cellulose utilization. A subsequent test with Congo Red dye could distinguish extracellular cellulolysis from intracellular type.

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Conveying Emotions Through CMC: A Comparative Study of Memoji, Emoji, and Human Face

  • Eojin Kim;Yunsun Alice Hong;Kwanghee Han
    • Science of Emotion and Sensibility
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    • v.26 no.4
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    • pp.93-102
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    • 2023
  • Emojis and avatars are widely used in online communications, but their emotional conveyance lacks research. This study aims to contribute to the field of emotional expression in computer-mediated communication (CMC) by exploring the effectiveness of emotion recognition, the intensity of perceived emotions, and the perceived preferences for emojis and avatars as emotional expression tools. The following were used as stimuli: 12 photographs from the Yonsei-Face database, 12 Memojis that reflected the photographs, and 6 iOS emojis. The results of this study indicate that emojis outperformed other forms of emotional expression in terms of conveying emotions, intensity, and preference. Indeed, the study findings confirm that emojis remain the dominant form of emotional signals in CMC. In contrast, the study revealed that Memojis were inadequate as an expressive emotional cue. Participants did not perceive Memojis to effectively convey emotions compared with other forms of expression, such as emojis or real human faces. This suggests room for improvement in the design and implementation of Memojis to enhance their effectiveness in accurately conveying intended emotions. Addressing the limitations of Memojis and exploring ways to optimize their emotional expressiveness necessitate further research and development in avatar design.

Studies on the Surfactants of the N-Acyl Amino Acid(part 10) -The Estimation of Theoretical cmc and Micellization Range by Computer Programming- (N-아실 아미노산계 계면활성제에 관한 연구(제10보) - 컴퓨터 프로그래밍에 의한 이론적 임계미셀농도 및 미셀화영역의 산정 -)

  • Kim, Tae-Young;Rho, Yun-Chan;Kim, Hong-Su;Kang, Yun-Seog;Nam, Ki-Dae
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.221-227
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    • 1996
  • Micellization range and cmc for the dilute aqueous solution of N-acyl amino acid type anionic surfactants, that is, sodium N-acyl-N-methyl-${\beta}$-alaninate, sodium N-acyl sarcosinate and sodium N-acyl-N-methyl taurate were investigated by computer programming. The extreme of the curvature of ${\sigma}(C)$ as a new suggested method to determine the cmc and the micellization range was accomplished with computer programming. The values of cmc and micellization range can be obtained by the extreme of the curve by direct processing of only a few experimental data. The values of cmc particulary was in good agreement with those deduced intuitively from the shape of experimental curves of ${\sigma}(C)$.

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Thermodynamic Study on the Mixed Micellization of Cationic Surfactants DPC and TTAB (양이온 계면활성제인 DPC와 TTAB의 혼합마이셀화에 대한 열역학적 고찰)

  • Lee, Byung Hwan
    • Journal of the Korean Chemical Society
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    • v.43 no.6
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    • pp.614-620
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    • 1999
  • The critical micelle concentration (CMC) and the counterion binding constant (${\beta}$) at the CMC of the mixtures of Dodecylpyridinium chloride (DPC) and Tetradecyltrimethylammonium bromide (TTAB) have been determined from the concentration dependence of electrical conductance at various temperatures from $4^{\circ}C$ to $36^{\circ}C$. Thermodynamic parameters (${\Delta}C_p$, ${\Delta}G^o_m$, ${\Delta}H^o_m$ and ${\Delta}S^o_m$), associated with the micelle formation of DPC/TTAB mixtures, have been estimated from the temperature dependence of CMC and ${\beta}$values. The measured values of ${\Delta}C_p$ and ${\Delta}G^o_m$ are negative but the values of ${\Delta}S^o_m$ are positive in the whole measured temperature region. The values of ${\Delta}H^o_m$ are positive at low temperature region and negative at high temperature region. The results show that all of the thermodynamic parameters are dependent on temperature and mole fraction of DPC(${\alpha}_DPC$).

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The Characteristic Changes of Corn Starch Gels by Various Types of Additives (여러가지 첨가제에 의한 옥수수전분 겔(Gel)의 특성변화)

  • 주난영;이혜수
    • Korean journal of food and cookery science
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    • v.7 no.2
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    • pp.19-23
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    • 1991
  • This study was conducted to compare the characteristics of reference starch gel and 5 additives-adding corn starch gels (agar, CMC, pectin, casein, gelatin). The sensory evaluation, textural analysis by Instron Universal Testing Machine were carried out The results were as follows: 1. In sensory evaluation. \circled1 The hardness of agar was significantly higher than that of control and the hardness of pectin was significantly lower than that of control. \circled2 The adhesiveness of CMC and pectin was significantly higher than that of control, and the adhesiveness of agar was significantly lower than that of control. \circled3 In acceptability, CMC and pectin were significantly higher than control and the other samples were not significantly different from control. 2. In textural analysis by Instron. \circled1 The hardness of agar was significantly higher than that of control and the hardness of the other samples was significantly lower than that of control. \circled2 The cohesiveness of agar and casein was significantly higher than that of control and the cohesiveness of gelatin was significantly lower than that of control. 3. In sensory evaluation or instrumental analysis by Instron. It was thought that the best sample-classifying characteristic was hardness.

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Synthesis and Properties of Glycidyl Succinate Type Cationic Gemini Surfactant (2-메틸숙신산을 이용한 에스테르계 제미니 양이온 계면활성제의 합성 및 물성)

  • Park, Jong-Kwon;Kim, Won-Kyun;Jeong, Noh-Hee
    • Journal of the Korean Applied Science and Technology
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    • v.30 no.2
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    • pp.312-319
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    • 2013
  • This study is to do with the synthesis of glycidyl succinate cationic gemini surfactant. The gemini surfactant was synthesized with using 2-methyl disodium succinate, epichlorohydrine and N,N-dimethyl dodecyl amine. The target material was confirmed by FT-IR, $^1H$-NMR and was tested their properties. Surface active properties such as surface tension, evaluated cmc, emulsing properties, foaming properties were measured respectively at given conditions. The surface tensions for the aqueous solution of gemini surfactant were 33~34 dyne/cm and their cmc values evaluated by surface tension method were $10^{-4}{\sim}10^{-3}mol/L$. Emulsing properties of gemini surfactant was better in organic solvent and foaming power was confirmed good stability.