• 생약학회지
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• 제35권2호통권137호
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• pp.164-170
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• 2004

The flavonoids are a very large and important group of polyphenolic natural products, which are united by their derivatization from the heterocycle, flavone. They are distributed in higher plants and occur widely in the fruits and vegetables that make up the human diet. They exhibit a wide range of biological properties, including antitumor, antiinflammatory, hepatoprotective, antimicrobial, insecticidal and estrogenic activities. They are also major components of many plant drugs and it is possible that they contribute to the curative properties. For the purpose of developing anticancer agent of natural origin, we have evaluated forty four kinds of naturally occurring flavonoids for the inhibitory activity upon the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.194-195
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• 1982

Recommendaton: These are the highlights of the findings of the Timber Consumption Survey carried out by the Project in 1966, and covering consumption for the period from 1961 to 1965. The survey was oriented towards consumption for structural, commercial and industrial purposes and existing estimates for local (village-level) consumption as fuel and the like were adopted. A full report on the survey was submitted to the Bureau of Forestry in 1966. Long-term Trends: After allowance for anticipated population increase, this ten year's increase in industrial wood consumption represents a gain of about 30% in per capita consumption (from 0.0913 cu.m. per capita to 0.118 cu.m. per capita). This is only about half the expected general economic growth of about 75% (7% per annum). It is therefore likely (a) that the 1975 estimate is conservative, (b) that the consumption demand beyond 1975 may be expected to build up at a greatly increased rate. Estimated income elasticity coefficients are high, and with expected ir,creases in prosperity and population, the consumption is expected to rise to 10 million cu. meters by the year 2,000. Consumption Pattern: The breakdown of industrial consumption (1965) is given in Table 4-2, showing sawnwood consumption as the most important in 1965. The upward trend in all sectors over the 1961-65 period is expected to continue. The general consumption pattern is expected to change through 1975 with a sharp increase in the relative importance of pulp products (to 30% of total consumption) offset by declining relative importance of sawlogs. The following recommendations follow from the study: (i) Industrial forests. - A programme of establishment of consolidated industrial forests should be initiated as a matter of urgency. (ii) Fuelwood forests - Properly sited, protected and managed fuelwood forest, worked on a 20-year rotation, should be established as a nation wide basis. (iii) Hardwood utilization - Detailed investigations are required into the use of indigenous hardwoods for the pulp, particle board and hardboard industries. (iv) Mining timber - Preservation treatment of all mining timber should be enforced by law. (v) Sawmills - Licencing restrictions should be enforced to reduce the number of small, inefficient sawmills. b. Extension work should be undertaken bv government to improve sawmilling practices.

• 펄프종이기술
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• 제48권3호
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• pp.5-13
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• 2016

This study investigated the effects of different factors on the migration of a fluorescent whitening agent (FWA) from paper treated with FWAs to non-fluorescent papers. FWA migration experiments were carried out in vertical and friction contacts between the papers dyed with FWAs and non-fluorescent papers. During the experiments, we identified the effects of the addition and types of FWAs, contact time, temperature, and relative humidity (RH) on FWA migration. The fluorescence indices of the non-fluorescent papers were measured before and after the migration experiments, and the Student's t test, a statistical tool, was utilized to compare results from different migration experiments. In vertical contact experiments, FWA migration to non-fluorescent paper was observed at $30^{\circ}C$ and 70% RH; this was attributed to the high moisture content of the paper. FWA migration did not occur significantly at $23^{\circ}C$ and 50% RH. In the friction contact experiments, FWA migrations were identified at both temperature conditions and RH percentages. The addition and types of FWAs did not increase the fluorescence index of non-fluorescent papers. Therefore, it was concluded that the moisture content of paper and the friction contact affected FWA migration from the papers containing internal and surface FWAs.

• 펄프종이기술
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• 제48권3호
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• pp.51-56
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• 2016

The most widely used glue in a corrugator is starch, which is a natural polymer. This material needs thermal energy to achieve a binding force, so a heating section is installed in a corrugator. However, this heating section can cause quality problems in linerboards and corrugating medium and increase the production cost because of the high cost of fossil resources. Therefore, a new adhesive that provides the binding force at lower temperatures than the conventional one must be developed. In this study, SB-latex was selected as a co-adhesive and added to the starch solution. The addition of the SB-latex was determined based on the viscosity of the new adhesive. The adhesive strength and the drying energy reduction of a corrugated board were measured to evaluate the functionalities of the new adhesive. The addition of SB-latex was determined to be under 20% of the oven-dried starch based on the viscosity of the new adhesive. The adhesive strength was improved and the drying energy was reduced by applying the new adhesive.

• 펄프종이기술
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• 제43권5호
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• pp.17-26
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• 2011

Drying behavior and physical properties of HwBKP, SwBKP, and OCC handsheets depending on kneading, refining and wet pressing were analyzed. The maximum drying shrinkage velocity was newly adopted to verify the effect of mechanical treatment of pulps by evaluating drying behavior according to varying the kneading, refining and wet pressing treatments. Those various treatments were changed to evaluate the relationship between the maximum drying shrinkage velocity and handsheets properties. When the drying shrinkage and the maximum drying velocity increased by refining and wet-pressing, handsheets strength was increased. The maximum drying shrinkage velocity showed higher correlation with physical properties of paper than WRV at different refining loads at SwBKP and mixed pulp. At high wet-web dryness, drying shrinkage, the maximum drying shrinkage velocity and strength properties of handsheet were increased. It meant that drying shrinkage behavior was highly affected by not only fibers' shrinkage but also fiber bonding. Kneading pre-treatment for KOCC and SwBKP effectively modified fiber properties and increasing paper strength and drying shrinkage. The effect of kneading pre-treatment was also confirmed by the maximum drying shrinkage velocity. Strength properties of mixed pulp handsheets were not increased by the kneading pre-treatment, although the maximum drying shrinkage velocity and WRV was increased. It meant that fibers network bonding of HwBKP was limited because of ves sels and ray cells' interference for bonding. Therefore in order to improve paper strengths containing HwBKP by mechanical treatments, interference of vessels and ray cells for fiber bondings should be carefully controlled.

• 한국균학회지
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• 제21권4호
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• pp.310-315
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• 1993

P. chrysosporium, SC 26 균주(菌株)를 이용하여 0.1% Tween 20, veratryl alcohol 및 benzyl alcohol 이 첨가된 배지(培地)에 접종(接種)한 후 진탕배양하여 ligninase역가를 조사한 결과는 다음과 같다. 배지(培地)에 Tween 20를 단독으로 처리했을 경우에는 ligninase 의 생성(生成)이 적었으나, 0.1% Tween 과 0.4 mM veratryl alcohol을 첨가했을 때 높았으며 , 최대 역가까지의 소요일수는 5일이었다. 또한 0.1% Tween 20 과 10 mM benzyl alcohol을 처리했을때 ligninase의 역가가 가장 높았으며, 최대 역가까지의 소요일수는 8일이였다.

• 보존과학연구
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• 통권31호
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• pp.9-16
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• 2010

The Annals of the Joseon Dynasty is one of the World Heritage which should be conserved well. However, some of wax treated volume of the Annals of the Joseon Dynasty have damaged seriously. Currently a variety of efforts to conserve and restore the injured volumes are continued and many studies about the aging mechanism of the wax treated volume have being progressed. The analysis of VOCs (Volatile Organic Compounds) emitted from paper cultural heritage is one of the methods to understand the degradation pathway of paper cultural heritage. The analysis of VOCs emitted from paper cultural heritage has been mainly conducted by SPME (Solid Phase Microextraction) method. SPME is potable and simple method but it is difficult to collect all VOCs emitted from a book such as the Annals of Joseon Dynasty. The dynamic chamber system has generally used to do analysis of VOCs emitted from the building materials, furniture and electric appliances. The chamber system is possible to do quantitative and qualitative analysis by a continuous $N_2$ gas flow and the proper chamber which is able to gather all VOCs emitted from the Annals of the Joseon Dynasty. In this study, the most material among detected VOCs was Naphthalene. Naphthalene has used to prevent organic cultural heritage from being damaged by various microbes for a long time. Apart from Naphthalene, main VOCs were Acetic acid, 2-Chloroethanol, 2-Bromoethanol, Furfural, 1-Methylnaphthalene, Azulene, and 2,4-Dioctylphenol. Of these VOCs, Furfural especially was known for a marker which represents a different emission rate according to the aging level.

• 보존과학연구
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• 통권31호
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• pp.79-88
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• 2010

Paper cultural heritages experience chemical and physical deterioration due to various factors including preservation environments and the property of paper materials1). Thus, it is important to develop optimal preservation and restoration methods for the damaged paper cultural heritages. Currently, lining is a popular treatment for the restoration of paper cultural heritages in Korea. Since lining paper is a layer of paper directly attached to the inside of cultural heritages for protection, understanding of the preservation properties of lining paper is primarily needed in order to devise the better preservation methods. The main material of lining paper is the paper mulberry, but additives such as chalk and white clay is sometimes used to enhance the preservation properties of lining paper. To date, the properties of the functional lining paper containing these additives have been not fully understood yet. In this study, dry heating aging at $105^{\circ}C$ and biological aging by the Aspergillus versicolor and Penicillium polonicum for the lining paper, which is made from paper mulberry and the chalk, are carried out to evaluate changes in their preservation properties by these aging factors. As a result, it is found that the functional lining paper containing 25.1% of chalk can control the growth of fungi, while the paper containing 32.7% of chalk do not show any protection effect. However, the functional lining paper added by chalk is more aged than the lining paper made from paper mulberry by dry heating accelerated aging.

• Journal of the Korean Wood Science and Technology
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• 제46권6호
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• pp.748-755
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• 2018

Timber from fast-growing tree species is susceptible to by biodeterioration attack, particularly subterranean termites. Impregnation with methyl methacrylate (MMA) potentially increases wood resistance to subterranean termite attack. Four wood species, namely sengon (Falcataria moluccana), jabon (Anthocephalus cadamba), mangium (Acacia mangium), and pine (Pinus merkusii), were impregnated with MMA, and samples of untreated and imidacloprid-preserved wood were prepared for comparison purposes. Small stakes, sized 0.8 cm by 2 cm in cross section by 20 cm in the longitudinal direction, were inserted into the ground for 3 months, and the weight loss of each specimen was determined at the end of the test period. A factorial $4{\times}3$ completely randomized design was used for data analysis; the first factor was wood species, and the second factor was treatment. The results showed that MMA polymer loadings were 27.88%, 24.91%, 14.14%, and 17.81% for sengon, jabon, mangium, and pine, respectively, and amounts of imidacloprid retention were $7.56kg/m^3$, $5.98kg/m^3$, $5.34kg/m^3$, and $9.53kg/m^3$, respectively. According to an analysis of variance, wood species, treatment, and interaction of both factors significantly affected the weight loss of wood specimens. Mangium had the smallest weight loss, followed by pine, sengon, and jabon. MMA impregnation into the wood increased the resistance of wood samples to subterranean termite attack during in-ground testing, but the resistance level was lower than that of imidacloprid-preserved wood. Except for mangium wood, the MMA treatment did not significantly affect resistance.

• 펄프종이기술
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• 제48권2호
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• pp.5-12
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• 2016

White waste papers are very important resources in the paper industry, but their use is limited because of the residual of fluorescent whitening agent (FWA). So the removal of FWAs from waste paper is an important task in the recycling process to improve the use of recycled resources. In this study, we focused on the FWAs used for surface treatments and carried out physical and chemical treatments to remove them from white waste papers. The white waste papers were disintegrated with a surfactant in different pH and temperature conditions, and then handsheets were made for the measurement of the fluorescence index, which is proportional to the amount of FWAs on papers. The effect of the flotation process on the removal of FWAs after disintegration was also investigated. The fluorescence index decreased as the disintegration time increased, but over a relatively long time, the fluorescence index increased again, which indicated the readsorption of the FWAs detached from the cellulosic fibers of the white waste papers. The lowest fluorescence index was shown when the waste papers were disintegrated with a 0.3% surfactant addition at pH 10 and at $45^{\circ}C$. However, the flotation treatment was not effective, because the flotation induced contact between the detached FWAs and the cellulosic fibers, and re-adsorption occurred.