• Journal of the Korean Wood Science and Technology
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• v.49 no.5
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• pp.416-429
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• 2021

Raru is a lesser-known plant species originating from North Sumatra, Indonesia. Information on the characteristics is still limited, especially its chemical component. Therefore, this study aims to examine the chemical composition information of Cotylelobium lanceolatum, Cotylelobium melanoxylon, and Vatica pauciflora woods based on their axial log positions (bottom, middle, and top). The wood chemical analysis was performed in terms of the Indonesian National Standard (SNI) method. Furthermore, the analysis measured holocellulose, 𝛼-cellulose, hemicellulose, lignin content, alcohol benzene extractive content, the extractive substance in hot and water, and solubility in NaOH 1%. The results indicated that the species and their log axial positions affected different chemical components, which included 𝛼-cellulose, hemicellulose, and lignin of C. lanceolatum amounting to 41.88%, 19.39%, and 28.68% respectively. Meanwhile, for C. Melanoxylon, they were 42.01%, 21.11%, and 24.76% respectively; and for V. pauciflora wood, they were 42.95%, 23.24%, and 30.11% respectively. The average values of the extractive contents including the solubility in 1: 2 ethanol benzene, NaOH, and hot water for C. lanceolatum, C. melanoxylon, and V. pauciflora wood were (10.58%, 27.62%, 8.13%), (14.54%, 28.22%, 7.82%), and (10.95%, 28.60%, 7.57%) respectively. The wood species had a significant effect on chemical components including lignin, cellulose and hemicellulose, and extractive solubility in cold water. Furthermore, the axial log position had a significant effect on all the parameters of the chemical composition of the wood being tested.

• Natural Product Sciences
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• v.10 no.1
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• pp.43-47
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• 2004

Pharmacognostic studies on the shape, microscopic structure, and morphology of Rumex nepalensis (Polygonaceae) were carried out. These studies provided referential information for identification of this crude drug.

• KSBB Journal
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• v.14 no.2
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• pp.212-219
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• 1999

lactic acid production from cellulose by simultaneous saccharification and fermentation(SSF) was studied. The SSF using cellulase enzyme Cytolase CL and Lactobacillus delbrueckii was strongly inhibited by the end product(lactic acid). An ion-exchange resin(RA-400) was used for in-situ product removal during SSF. The sorption capacity of the resin was 200mg/g-resin. The simple SSF and the extractive SSF resulted in lactic acid concentrations of 30.4g/L and 32.0g/L, respectively, at the initial substrate concentration of 50g/L. A model was developed to simulate the extractive SSF. The lactic acid conversion for the initial substrate of 100g/L was estimated to be improved from 60% to 09% by in-situ product removal. The experimentally determined kinectic parameters were pH dependent, and fitted as empirical expressions to establish their values at different pH's. Lactic acid productivity was predicted to be maximum at pH 4.5-5.0.

• Korean Journal of Metals and Materials
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• v.46 no.1
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• pp.20-25
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• 2008

The ionic equilibira in mixed solutions of cuprous and cupric chloride were analyzed by considering chemical equilibria, mass and charge balance equations. The activity coefficients of solutes were calculated by using Bromley equation. Required thermodynamic constants and interaction parameters were evaluated from the data reported in the literature. The effect of NaCl and CuCl concentrations on the pH and potential of the mixed solutions was explained in terms of the variation in the concentration of solutes and in the activity of hydrogen ion. The calculated pH values of the mixed solutions agreed well with the measured values. However, the calculated values for the potential of the mixed solutions were lower than the measured values, indicating the necessity of considering the complex formation between cuprous and chloride ion, such as $Cu^2Cl{_4}^{2-}$ and $Cu_3Cl{_6}^{3-}$.

• KSBB Journal
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• v.24 no.5
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• pp.446-452
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• 2009

Oleyl alcohol, butyl butyrate, and two different ionic liquids were evaluated for the extraction of butanol from culture broth without toxic effect to cells. The tested solvents showed more than 50% extraction efficiency, and oleyl alcohol was chosen as the best extractant for butanol among the used extractants with a partition coefficient of 2.89. When oleyl alcohol was used as an extractant, more than 80% of butanol was extracted in the wide range of butanol concentrations (1-20 g/L) and pH values (pH 4-5.5). In extractive fermentation using oleyl alcohol only, there was 11% more butanol production and glucose consumption when compared to that without extractive fermentation, implicating a reduced inhibitory effect of butanol due to butanol removal to the oleyl alcohol phase. In addition, oleyl alcohol did not inhibit cell growth, while a mixture of oleyl alcohol and butyl butyrate with the volume ratio of 9:1~7:3 inhibited either butanol production or cell growth significantly due to the toxicity of butyl butyrate to cells. In conclusion, oleyl alcohol can be used as an efficient and non-toxic solvent for extractive fermentation for butanol production.

• Journal of Magnetics
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• v.2 no.1
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• pp.12-15
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• 1997

Fe-(3∼6.5wt%) Si alloy powders having a high magnetic induction(Bs) and a low core loss value for high frequency use were obtained by an extractive melt spinning as well as a centrifugal atomization technique. Sintered core rings made by the rapidly solidified Fe-6.5wt% Si powders exhibited the high frequency magnetic properties : megnetic induction(B8) of 1.23 T, coercivity(Hc) of 0.12 Oe, relative permeability(${\mu}$a) of 6321, and core loss(W10/50) of 1.27 W/kg from the rings of 1.1 mm thick. The magnetic induction values were found to be almost identical to those of non-oriented Fe-6.5wt% Si steel sheet and double the value of 6.5wt% Si sheet prepared by the CVD technique. The high frequency core losses(W) up to 10 kHz(W10/10k) were measured to be competitive to those of grain-oriented Fe-6.5wt% Si steel sheet.

• Journal of Korean Society of Rural Planning
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• v.14 no.4
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• pp.1-9
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• 2008

Many urban people are attracted to the recreational opportunities and attractions of rural areas, such as beautiful scenery, lakes, mountains, forests, and resorts. Furthermore, rural development planning increasingly emphasizes the integration of resource extractive industries with non-market-based recreational and amenity values. This article outlines a method to estimate an amenity level of rural areas such as natural amenities index and shows the relation of the natural amenity and population growth. The results revealed that natural amenity classifying each region can be explained with geographical characteristics, temperature-humidity, and sunshine duration time. In analysis with population, natural amenity does not exactly explain that but can be one of the important factor of population change.

• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.370-373
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• 2000

In this work, an extractive membrane bioreactor containing coulture broth of Burkholderia cepacia G4 PR1 constitutively expressing the TCE-degrading enzyme, tolune-ortho-monooxygenase(TOM), was used for the degradation of TCE. The membrane bioreactor operates by seperating the TCE-containing waste gas from the aerated biomedium, by which the air-stripping of TCE without degradation was overcome that could occur in conventional aerobic biological treatments of TCE-contaminated waste gases. This was achieved by a silicone rubber membrane which was coiled around a perspex draft tube. TCE from the gas phase diffuses across the silicone rubber membrane into microbial culture broth that was continuously fed from a separate aerobic CSTR. Therefore, TCE degradation occured without the TCE being directly exposed to the aerating gas stream. Of the TCE supplied to the membrane bioreactor, 72.6% was biodegraded during the operation of this system. To construct a mathematical model for this system, parameters describing microbial growth kinetics on TCE were determined using a CSTR bioreactor. Else parameters used for numerical simulation were determined from either indepedent experiments or values reported in the literature. The model was compared with the experimental data, and there was a good agreement between the predicted and the measured TCE concentrations in the system. To achieve a higher treatment efficiency, various operating conditions were simulated as well.

• Journal of Powder Materials
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• v.20 no.3
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• pp.174-179
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• 2013

The study on the fabrication of iron powder from forging scales using hydrogen gas has been conducted on the effect of hydrogen partial pressure, temperature, and reactive time. The mechanism for the reduction of iron oxides was proposed with various steps, and it was found that reduction pattern might be different depending on temperature. The iron content in the scale and reduction ratio of oxygen were both increased with increasing reactive time at 0.1atm of hydrogen partial pressure. On the other hand, for over 30 minutes at 0.5 atm of hydrogen partial pressure, the values were found to be almost same. In the long run, iron metallic powder was obtained with over 90% of iron content and an average size of its powder was observed to be about $100{\mu}m$.

• Journal of the Korean Wood Science and Technology
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• v.37 no.4
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• pp.414-420
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• 2009

We dyed traditional Korean hand-made papers (Hanji) with colorants extracted from fruits of Alnus japonica to investigate the effect of various dyeing factors (mordant, dye concentration and dyeing assistant) on colors, K/S values and light fastness of the dyed Hanji. The dyed hanji had brown color. The K/S value of dyed Hanji was increased by mordanting with alum and copper acetate. $a^*$ and $b^*$ value of dyed Hanji was decreased slightly by mordanting with alum and Iron(II) chloride. The K/S value and $b^*$ of dyed Hanji increased with increasing concentration of dye, but $L^*$ value of dyed Hanji decreased. The K/S value of dyed Hanji was also increased by fixing agent. When Hanji was mordanted with Iron(II) chloride and was not mordanted, use of fixing agent resulted in greater increase of K/S value. Use of fixing agent resulted in poor light fastness. When fixing agent was used, mordanting with copper acetate resulted in smaller color difference than mordanting with alum after aging test.