• Title/Summary/Keyword: pH paper

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Physicochemical Characteristics Study on Wheat Starch Adhesive - Based on Wheat Starch Adhesive fermenting period less than two years- (소맥전분 풀의 이화학적 특성 연구 - 수침기간이 2년 이하인 풀을 중심으로-)

  • Chung, Yong-Jae;Kim, Min-Jeong;Nam, Seo-Jin;Jeong, Seon-Hye
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.2
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    • pp.35-41
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    • 2012
  • In this study, wheat starch adhesive was investigated the shape and structure of starch, the difference in characteristics such as chemical composition according to the fermenting period of 2 years or less. The fermenting period of wheat starch adhesive is 1 month, 2months, 4 months,6 months, 1 year, 2years old. The wheat starch adhesives were investigated total sugar contents, protein contents, properties of gelatinization, pH, the bonding strength and also observed the surface of starch,. As a result, the longer the fermenting period, the increasing in total sugar contents and decreasing in protein contents. The particle shape and surface were similar regardless of the period. In addition, properties of gelatinization according to the fermenting period also could not see the difference. In pH of the adhesive, the longer the fermenting period, the near to neutral. The adhesive was high bonding strength in 4 months, but appeared a tendency to decrease from 6 months. The damage assessment through the UV degradation in regard to the papers applied the adhesive was accomplished. Color difference was no change except 1 month. The 4 months and 6 months' pH was each 5.0, 5.2. But it was near to neutral that the 12 months and 24 months' pH was each 5.7, 5.9.

Purification and Characterization of Laccase from Wood-Degrading Fungus Trichophyton rubrum LKY-7

  • Hyunchae Jung;Park, Chongyawl;Feng Xu;Kaichang Li
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 2001.04a
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    • pp.18-25
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    • 2001
  • A new wood-degrading fungus Trichophyton rubrum LKY-7 secretes a high level of laccase in a glucose-peptone liquid medium. The production of laccase by the fungus was barely induced by 2,5-xylidine. The laccase has been purified to homogeneity through three chromatography steps in an overall yield of 40%. The molecular mass of the purified laccase was about 65 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified laccase had the distinct blue color and had basic spectroscopic features of a typical blue laccase: two absorption maxima at 278 and 610 nm and a shoulder at 338 nm. The N-terminus of the laccase has been sequenced, revealing high homology to laccases from wood-degrading white-rot fungi such as Ceriporiopsis subvermispora. The enzyme had a "low" redox potential (0.5 V vs normal hydrogen electrode), yet it was one of the most active laccases in oxidizing a series of representative substrates/mediators. Compared with other fungal laccases, the laccase has a very low Km value with ABTS [2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid] as a substrate and a very high Km value with violuric acid as a substrate. The laccase has the isoelectric point of 4.0. The laccase had very acidic optimal pH values (pH 3-4) while it was more stable at neutral pH than at acidic pH. The laccase oxidized hydroquinone faster than catechol and pyrogallol. The oxidation of tyrosine by the laccase was not detectable under the reaction conditions. The laccase was strongly inhibited by sodium azide and sodium fluoride. fluoride.

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Screening of Microorganisms Secreted High Efficient Enzymes and Properties of Enzymatic Deinking for Old Newsprint(III) -Production of bacterial cellulase and xylanase for enzymatic deinking of old newsprint- (고효율 효소를 분비하는 균주의 선발 및 신문고지의 효소탈묵 특성(제3보) -고지탈묵용 Bacterial Cellulase와 Xylanase의 생산-)

  • Park Seong-Cheol;Kang Jin-Ha;Lee Yang-Soo
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.1 s.109
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    • pp.25-37
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    • 2005
  • This study was carried out to examine the optimal cultural condition in enzyme activities of CMCase, FPase and xylanase in selected strains which secret extracellular enzymes for using deinking agent to old newsprint. The results of this study were as follow: The production of enzyme by Bacillus pumilus I was maximal as grown on the medium, containing of rice bran+xylan $2.0\%$, peptone $0.8\%,\;K_2HPO_4\;0.1\%\;and\;CaCl_2\;0.06\%$ at pH 8.0 and $28^{\circ}C$ for 72 hours. Optimal cultural condition of B. subtilis I was avicel+xylan $3.5\%,\;urea\;0.4\%,\;K_3PO_4\;0.1\%\;and\;CaCl_2\;0.015\%$ at pH 9.0 and $28^{\circ}C$ for 36 hours. The maximal enzyme production was observed in the medium, containing of avicel+xylan $3.5\%,\;urea\;1.6\%\;and\; K_2HPO_4\;0.125\%$ with pH 9.0 when B. pumilus II was cultured at $28^{\circ}C$ for 60 hours. The production of enzyme by B. subtilis IT was maximal as grown on the medium, containing of xylan $2.0\%,\;yeast\; extract\;0.6\%,\;K_2HPO_4\;0.1\%\;and\;ZnSO_4\;0.04\%$ at pH 8.0 and $34^{\circ}C$ for 36 hours. The activities of FPase and xylanase in tested 4 strains were not much different with Thermomonospora fusca.

Studies on Cellulase -Part 1. Isolation of Cellulase Forming Microorganisms and the Properties of Crude Enzymes- (Cellulase에 관(關)한 연구(硏究) -(제1보(第一報)) Cellulase 생성균(生成菌)의 분리(分離)와 조효소(粗酵素)의 제성질(諸性質)-)

  • Chung, Dong-Hyo
    • Applied Biological Chemistry
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    • v.11
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    • pp.109-117
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    • 1969
  • Out of some 400 strains of Microorganisms, cellulase forming organisms was isolated from night soil during the course of screening tests. Two strains, Ku-3371 and Ku-4383 were found capable of producing cellulase in the shaking culture. General properties of the crude enzyme were as the following results. 1. The optimum pH values on CMC-saccharifying, CMC-liquefying and filter paper disintegrating activities were 4.0 to 5.5. 2. The stable pH range was within 3.5 to 6.5, 3. The optimum temperature was $40-45^{\circ}C$, the thermal stability was below $50^{\circ}C$ except on paper disintegrating activity and completely inactivated at $70^{\circ}C$. 4. Dialyzed crude enzyme was activated by $Mn^{2+}\;and\;Co^{2+}$ repectively but $Hg^{2+}$ was strong inhibitor.

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Objectively Predicting Ultimate Quality of Post-Rigor Pork Musculature: I. Initial Comparison of Techniques

  • Joo, S.T.;Kauffman, R.G.;Warner, R.D.;Borggaard, C.;Stevenson-Barry, J.M.;Lee, S.;Park, G.B.;Kim, B.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.1
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    • pp.68-76
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    • 2000
  • A total of 290 pork loins were selected to include a wide variation of quality to investigate the quality categories into which most pork falls, selection criteria for these categories and methods to objectively assess ultimate pork quality. They were probed at 24 h postmortem (PM) for the following: A) light reflectance by Danish Meat Quality Marbling (MQM), Hennessy Grading Probe (HGP) and Sensoptic Invasive Probe (SIP); B) electrical properties by NWK LT-K21 conductivity (NLT) and Sensoptic Resistance Probe (SRP): and C) pH by NWK pH-K21 (NpH). Also, measurements of % drip loss (PDL) and filter paper wetness (FPW), color brightness (L*), ultimate pH (pHu), lipid content, subjective color (SC), firmness/wetness (SF) and marbling scores (SM) were assessed. Each loin was categorized as either pale, soft and exudative (PSE), reddish-pink, soft and exudative (RSE), reddish-pink, firm and non-exudative (RFN) or dark, firm and dry (DFD). Statistically comparing coefficients of determination (CD), the results indicated that overall, the HGP predicted quality groups slightly better than MQM (CD=71 and 62% respectively), NpH and SRP were less effective (CD= 56 and 44% respectively), and SIP and NLT had the lowest values (CD=36 and 5% respectively). Combining various independent variable did not greatly improve the variation accounted for. When the data was sorted into marbling groups based on lipid content, this was not accurately predicted by any of the probe measurements. The MQM probe remained the best predictor for marbling class and accounted for about 25% of the lipid content variation. This was slightly improved to 33% when pHu was combined with MQM.

Synthesis, Molecular and Microstructural Study of Poly-N-Vinylpyrrolidone Oximo-L-Valyl-Siliconate with IR, 1H-NMR and SEM

  • Singh, Man;Padmaja, G. Vani
    • Bulletin of the Korean Chemical Society
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    • v.31 no.7
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    • pp.1869-1874
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    • 2010
  • By reducing PVP with $H_2NOH$.HCl and NaOH 2:2:1 mass ratios in aqueous ethanol, poly-N-vinyl pyrrolidone oxime [PVPO] was prepared with 92% yield. Applying the sol-gel concept, orthosilicic acid [OSA] was made by hydrolyzing TEOS with ethanol in 1:0.5 molar ratios using 1 N KOH aqueous solution as a catalyst. The OSA + PVPO + $_L$-Valine ($\alpha$-amino acid) were mixed with pure ethanolic medium in 1:2:2 mass ratios and refluxed at $78^{\circ}C$ and 6 pH for 6.5 h. A white residue of poly-N-vinyl pyrrolidone oximo-L-valyl-siliconate [POVS] appeared after 5 h. The heating of reaction mixture was stopped and the contents were brought to NTP. The residue formation of POVS was intensified with lowering a temperature and completely solidified within 5 h, was filtered using a vacuum pump with Whatmann filter paper no. 42. The residue of POVS was washed several times with 20% aqueous cold ethanolic solution and dried in vacuum chamber at $25^{\circ}C$ for 24 h. The MP was noted above $350^{\circ}C$. Structural and internal morphology were analyzed with IR and $^1H$-NMR, and SEM respectively. A drug loading and transporting ability of the POVS in water and at pH = 5 and 8 was determined chromatographically.

Range Kernel Orthogonality and Finite Operators

  • Mecheri, Salah;Abdelatif, Toualbia
    • Kyungpook Mathematical Journal
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    • v.55 no.1
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    • pp.63-71
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    • 2015
  • Let H be a separable infinite dimensional complex Hilbert space, and let $\mathcal{L}(H)$ denote the algebra of all bounded linear operators on H into itself. Let $A,B{\in}\mathcal{L}(H)$ we define the generalized derivation ${\delta}_{A,B}:\mathcal{L}(H){\mapsto}\mathcal{L}(H)$ by ${\delta}_{A,B}(X)=AX-XB$, we note ${\delta}_{A,A}={\delta}_A$. If the inequality ${\parallel}T-(AX-XA){\parallel}{\geq}{\parallel}T{\parallel}$ holds for all $X{\in}\mathcal{L}(H)$ and for all $T{\in}ker{\delta}_A$, then we say that the range of ${\delta}_A$ is orthogonal to the kernel of ${\delta}_A$ in the sense of Birkhoff. The operator $A{\in}\mathcal{L}(H)$ is said to be finite [22] if ${\parallel}I-(AX-XA){\parallel}{\geq}1(*)$ for all $X{\in}\mathcal{L}(H)$, where I is the identity operator. The well-known inequality (*), due to J. P. Williams [22] is the starting point of the topic of commutator approximation (a topic which has its roots in quantum theory [23]). In [16], the author showed that a paranormal operator is finite. In this paper we present some new classes of finite operators containing the class of paranormal operators and we prove that the range of a generalized derivation is orthogonal to its kernel for a large class of operators containing the class of normal operators.

Study on the degradation rate and pH change of PLGA membrane with a biodegradation (생분해에 따른 PLGA 멤브레인의 분해속도 및 pH 변화에 대한 연구)

  • Xie, Yuying;Park, Jong-Soon;Kang, Soon-Kook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.9
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    • pp.6403-6410
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    • 2015
  • Medical polymer PLGA is biocompatible, biodegradation, mechanical characteristic and biostability, and the degradation time can be adjust by controlling the number of monomer. In this paper, PLGA membranes have different composition ratio by L/D type was prepared by phase transition method. And the PLGA membrane in phosphate buffered saline(PBS) at the different test temperatures for different periods of time to examined for change in mass and measured the pH of degradation media. Measurement of Tg and surface structure was performed using a DSC and Stereoscopic microscope. As the molecular weighter increase, hydrolysis rate was decrease in geometrical progression. According to the composition ratio by L/D type, degradation rate and the change of pH are large.

Physical Characteristics of Floc Density of Suspended Fine Particles in accordance with the Cohesiveness (점착성에 따른 부유 미립자의 플럭밀도에 대한 물리적 특성)

  • Choi, In Ho;Kim, Jong Woo
    • Journal of Wetlands Research
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    • v.20 no.3
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    • pp.227-234
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    • 2018
  • This paper was examined the physical characteristics of floc density of suspended fine particles with varying cohesiveness. The analysis of floc density was performed in a small annular flume with a free water surface under different bed shear stresses and ion addition. Fine-grained silica was used as model material, as it is the main mineral components of clay that affects sedimentation. It was concluded that floc density depended on increasing the bed shear stress, the salinity and pH value. Floc density decreased with increasing the salinity in still water and floc size, whereas the opposite was true when increasing the bed shear stress. Also, it increased at pH6.8 more than at pH4.2 when increasing the bed shear stress in the range from 0.0086 to $0.0132N/m^2$.

A Novel Photovoltaic Power Harvesting System Using a Transformerless H6 Single-Phase Inverter with Improved Grid Current Quality

  • Radhika, A.;Shunmugalatha, A.
    • Journal of Power Electronics
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    • v.16 no.2
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    • pp.654-665
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    • 2016
  • The pumping of electric power from photovoltaic (PV) farms is normally carried out using transformers, which require heavy mounting structures and are thus costly, less efficient, and bulky. Therefore, transformerless schemes are developed for the injection of power into the grid. Compared with the H4 inverter topology, the H6 topology is a better choice for pumping PV power into the grid because of the reduced common mode current. This paper presents how the perturb and observe (P&O) algorithm for maximum power point tracking (MPPT) can be implemented in the H6 inverter topology along with the improved sinusoidal current injected to the grid at unity power factor with the average current mode control technique. On the basis of the P&O MPPT algorithm, a power reference for the present insolation level is first calculated. Maintaining this power reference and referring to the AC sine wave of bus bars, a sinusoidal current at unity power factor is injected to the grid. The proportional integral (PI) controller and fuzzy logic controller (FLC) are designed and implemented. The FLC outperforms the PI controller in terms of conversion efficiency and injected power quality. A simulation in the MATLAB/SIMULINK environment is carried out. An experimental prototype is built to validate the proposed idea. The dynamic and steady-state performances of the FLC controller are found to be better than those of the PI controller. The results are presented in this paper.