• 제목/요약/키워드: carboxymethylcellulose

검색결과 113건 처리시간 0.023초

EDLC용 활성탄소 전극의 전기화학적 기계적 특성에 미치는 바인더의 영향 (Effect of Binders on Electrochemical and Mechanical Properties of Activated Carbon Electrode for Electric Double Layer Capacitor)

  • 전민제;김익준;양선혜;문성인;김현수;오대희
    • 한국전기전자재료학회논문지
    • /
    • 제19권12호
    • /
    • pp.1167-1171
    • /
    • 2006
  • This work describes the effect of binders, such as carboxymethylcellulose (CMC), CMC+ Polytetrafluoroethylene (PTFE) and PTFE, on the electrochemical and mechanical properties of activated carbon-electrode for electric double layer capacitor. The cell capacitors using the electrode bound with binary binder composed of CMC and PTFE, especially in composition CMC PTFE = 60 : 40 wt.%, has better rate capability and the lower internal resistance than those of the cell capacitor with CMC. On the other hand, the sheet type electrode kneaded with PTFE was bonded with conductive adhesive on Al foil. This cell capacitor using the electrode with PTFE exhibited the best mechanical properties and rate capability compared to the CMC and CMC+PTFE one. These behaviors could be explained by the well-developed network structure of PTFE fibrils doting the kneading process.

CMC+PTFE 혼합바인더 전극의 제조 및 전기화학적 특성 (Fabrication of CMC+PTFE Electrode and it's Electrochemical Performances)

  • 김익준;이선영;문성인
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
    • /
    • pp.1248-1253
    • /
    • 2004
  • This work describes the effect of electrode binder on the characteristics of electric double layer capacitor Among carboxymethylcellulose (CMC), Polyvinylpyrrolidone (PVP), Polyvinyl Alcohol (PVA), and Polyvinylidene Fluoride (PVDF), the unit cell using CMC showed good rate capability between $2.5mA/cm^2{\sim}100mA/cm^2$ current density. However, CMC as a binder is incongruent, because the electrode bound with CMC is rigid and easy to crack during a press and winding process for fabrication of capacitor. The unit cell capacitor using the electrode bound with binary binder composed of CMC and Polytetrafluoroethylene (PTFE), especially in composition CMC : PTFE : 60 : 40 wt.%, has exhibited the better mechanical properties than those of the unit cell with CMC. On the other hand, it was also noted that the mechanical properties of CMC+PTFE electrode, coated on underlayer composed of CMC and carbon black, were much improved the binding force.

  • PDF

Degradation Characteristics of A Novel Multi-Enzyme-Possessing Bacillus licheniformis TK3-Y Strain for the Treatment of High-Salinity Fish Wastes and Green Seaweeds

  • Kang, Kyeong Hwan;Kim, Joong Kyun
    • Fisheries and Aquatic Sciences
    • /
    • 제18권4호
    • /
    • pp.349-357
    • /
    • 2015
  • To reutilize fisheries waste, we isolated a bacterial strain from a coastal area located in Busan. It was identified as Bacillus licheniformis TK3-Y. Using plate assay and 500-mL flask experiments, we found that the isolate simultaneously possessed cellulolytic, proteolytic, and lipolytic activities with salt tolerance. 10% (v/v) inoculums, were used to examine the biodegradation characteristics of the TK3-Y strain on carboxymethylcellulose, skim milk, and olive oil media. The optimum conditions for pH, temperature, agitation speed, and NaCl concentration on each 1% substrate were 6, $50^{\circ}C$, 180 rpm, and 17.5%, respectively. Under optimal conditions, the TK3-Y strain showed 1.07 U/mL cellulolytic, 1,426 U/mL proteolytic, and 6.45 U/mL lipolytic activities. Each enzyme was stable within a range of 17.5-35% NaCl. Therefore, the salt tolerance ability of strain TK3-Y was superior to other related strains. In degradation of a mixed medium containing all three substrates, both the cellulolytic and proteolytic activities were somewhat lower than those on each single substrate, while the lipolytic activity was somewhat higher. From the above results, the TK3-Y strain appears to be a good candidate for use in the efficient treatment of fisheries waste in which components are not collected separately.

Purification and Characterization of the Bacillus sp. KK-l $\beta$-Xylosidase from a Recombinant Escherichia coli

  • Jung, Kyung-Hwa;Chun, Yong-Chin;Lee, Jae-Chan;Park, Seung-Hwan;Yoon, Ki-Hong
    • Journal of Microbiology and Biotechnology
    • /
    • 제8권3호
    • /
    • pp.258-263
    • /
    • 1998
  • ${\beta}$-Xylosidase was purified from the recombinant Escherichia coli carrying the Bacillus sp. KK-1 ${\beta}$-xylosidase gene (xylB). The molecular mass of the purified enzyme was estimated to be 62 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, the apparent molecular mass of the ${\beta}$-xylosidase was 140 kDa, indicating that the native ${\beta}$-xylosidase has an oligomeric structure composed of two identical subunits. The isoelectric point was determined to be pH 5.5. The enzyme was highly active on p-nitrophenyl-$\beta$-D-xylopyranoside but it barely hydrolyzed xylan substrates, and did not exhibit activity towards carboxymethylcellulose and p-nitrophenyl-${\beta}$-D- glucopyranoside. The enzyme had a pH optimum for its activity at pH 6.5 and a temperature optimum at $40^{\circ}C$. The enzyme activity was completely inhibited by the presence of $Hg^{++}$, and also markedly inhibited by D-xylose and D-glucose.

  • PDF

내열성 Cellulase-free Xylanase를 생산하는 고온성 Bacillus sp.의 분리 및 효소 특성 (Isolation of a Thermophilic Bacillus sp. Producing the Thermostable Cellulase-free Xylanase,and Properties of the Enzyme)

  • 김대준;신한재;민본홍;윤기홍
    • 한국미생물·생명공학회지
    • /
    • 제23권3호
    • /
    • pp.304-310
    • /
    • 1995
  • A thermophilic bacterium producing the extracellular cellulase-free xylanase was isolated from soil and has been identified as Bacillus sp. The optimal growth temperature was 50$\circ$C and the optimal pH, 7.0. Under the optimal growth condition, maximal xylanase production was 2.2 units/ml in the flask culture. The enzyme production was induced by xylan and xylose, but was repressed by sucrose or trehalose. The partially purified xylanase was most active at 70$\circ$C. It was found that the enzyme was stable at 65$\circ$C for 10 hours with over 75% of the activity. The enzyme was most active at pH 7.0 and retained 90% of its maximum activity between pH 5.0 and pH 9.0 though Bacillus sp. was not grown on alkaline conditions (>pH 8.0). In addition, the activity of xylanase was over 60% at pH 10.0. At the ambient temperature, the enzyme was stable over a pH range of 5.0 to 9.0 for 10 h, indicating that the enzyme is thermostable and alkalotolerant. The activity of xylanase was completely inhibited by metal ions including Hg$^{2+}$ and Fe$^{2+}$, while EDTA, phenylmethylsulfonyl fluoride (PMSF), $\beta$-mercaptoethanol and SDS didn't affect its activity. The enzyme was also identified to exert no activity on carboxymethylcellulose, laminarin, galactomannan, and soluble starch.

  • PDF

EDLC용 CMC+PTFE 혼합바인더 전극의 전기적, 기계적 특성 (Electric and Mechanical Properties of CMC+PTFE Binary Binder Electrode for Electric Double Layer Capacitor)

  • 김익준;이선영;문성인
    • 한국전기전자재료학회논문지
    • /
    • 제17권10호
    • /
    • pp.1079-1084
    • /
    • 2004
  • This work describes the effect of electrode binder on the characteristics of electric double layer capacitor. Among carboxymethylcellulose (CMC), Polyvinylpyrrolidone (PVP), Polyvinyl Alcohol (PVA), and Polyvinylidene Fluoride (PVDF), the unit cell using CMC showed good rate capability at current densities between 2.5 mA/$\textrm{cm}^2$~100 mA/$\textrm{cm}^2$. However, CMC as a binder is incongruent, because the electrode bound with CMC is rigid and easy to crack during a press and winding process for fabrication of capacitor. The unit cell capacitor using the electrode bound with binary binder composed of CMC and Polytetrafluoroethylene (PTFE), especially in composition CMC : PTFE =60 : 40 wt.%, has exhibited the better mechanical properties than those of the unit cell with CMC. On the other hand, the mechanical properties of CMC+PTFE electrode, coated on underlayer composed of CMC and carbon black, were much improved.

Hyper-CMCase-Producing Mutants of Bacillus sp. 79-23 Induced by Gamma- Radiation

  • Yoon, Ki-Hong;Shin, In-Kyung;Jung, Kyung-Hwa;Park, Seung-Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • 제9권4호
    • /
    • pp.518-521
    • /
    • 1999
  • Bacillus sp. 79-23 spores were irradiated with $^{60}Co$ gamma-rays at doses ranging from 0.5 to 5 kGy. Following gamma-irradiation, seven mutant strains were isolated by scoring the halo sizes formed around the colonies grown on LB agar plates containing 4% carboxymethylcellulose (CMC) and trypan blue. The mutant strains showed a 1.5 to 2-fold increase in carboxymethylcellulase (CMCase) activity over the parent strain. Wheat bran acted as an effective inducer for CMCase production in the parent and mutant strains. Mutant strains 68 and 70 were identified as exhibiting higher CMCase activities than those of other mutants in LB media both with and without 3% wheat bran. In addition, these strains seem to produce substantially lower amounts of capsular materials, whereas the parent strain produced large amounts of them in both liquid and solid LB media. In flask cultures, the CMCase production by mutants 68 and 70 reached maximum levels of 17.5 unit/ml and 15.7 unit/ml, respectively, in an LB medium containing 3% wheat bran.

  • PDF

리도카인을 함유하는 마이크로에멀젼 겔의 피부침투성 및 in vivo 마취효과 (Skin Penetration and in Vivo Local Anesthetic Effect of Microemulsion-based Hydrogels Containing Lidocaine)

  • 신현우;이기봉;이상길;최영욱
    • Journal of Pharmaceutical Investigation
    • /
    • 제30권4호
    • /
    • pp.273-278
    • /
    • 2000
  • Several topical preparations containing lidocaine, a widely used local anesthetic agent, have been developed and marketed recently for the treatment of premature ejaculation. In this study, microemulsion(ME)-based hydrogels containing lidocaine were prepared by dispersing ME to hydrogel bases such as Carbopol, sod. alginate, and sod. carboxymethylcellulose. Lidocaine-containing ME was thermodynamically stable over 6 months and had a diameter ranging from 10 to 100 nm. In vitro skin penetration of lidocaine from ME-based hydrogels followed apparent zero-order kinetics. ME-based hydrogel showed higher drug penetration during fifteen minutes after application than alcoholic hydrogel, reference preparation. Tail flick test in rat was introduced to compare in vivo local anesthetic effects of different hydrogels, and the results showed that ME-based hydrogels are superior to other hydrogels. In optical microscopy, recrystallization of lidocaine was observed within 5 min after application of reference hydrogel, but there was no change in ME-based hydrogels even after 30 minnute. These results indicated that ME-based hydrogels had some advantages in skin penetration, anesthetic effect and physical stability compared with alcoholic hydrogels. Finally it is possible to conclude that ME-based hydrogels containing lidocaine is a good topical drug delivery system for the treatment of premature ejaculation.

  • PDF

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

  • 홍순우;하영칠;민경희;이영하
    • 미생물학회지
    • /
    • 제14권1호
    • /
    • pp.17-24
    • /
    • 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.

  • PDF

Purification of Cellulase from Trichoderma viride and properties of Its Component Enzymes

  • Dong Won Kim;Tae Seung Kim
    • Bulletin of the Korean Chemical Society
    • /
    • 제15권9호
    • /
    • pp.719-724
    • /
    • 1994
  • Major cellulase components, such as three endoglucanases (endoglucanases I, II, and III) and one exoglucanase (exoglucanase II), were isolated from a commercial cellulase (Meicelase TP 60) derived from the fungus Trichoderma viride by a series of chromatography procedures. These procedures were the gel filtration on Bio-Gel, the anion exchange on DEAE-Bio-Gel A, the cation exchange on SP-Sephadex C50, and the affinity chromatography on Avicel cellulose. The average molecular weights determined by SDS-polyacrylamide gel electrophoretic analysis were 51,000, 59,000, 41,000 and 62,000 Da for endoglucanases I, II and III and exoglucanase II, respectively. The extinction coefficients, ${\varepsilon}^{1%}$ 280 nm, of these enzymes were 11.7, 3.3, 7.2 and 11.3, respectively. Among them, the endoglucanase II showed the very low value of the coefficient compared with the others. On the other hand, it was found that endoglucanase II and III were of more random hydrolytic mode on carboxymethylcellulose as compared with those of endoglucanase I and exoglucanase II. Especially, endoglucanase I showed less random action than that of exoglucanase II. In the hydrolysis of insoluble cellulose by the enzyme components, cellobiose was the major product, but glucose was the major product by endoglucanase III.