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On the Milled Wood Lignins Isolated from Hardwood by Progressive Milling (단계적(段階的) 분쇄법(粉碎法)에 의해 조제(調製)된 활엽수(闊葉樹) MWL에 관한 연구(硏究))

  • Cho, Nam Seok
    • Journal of Korean Society of Forest Science
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    • v.45 no.1
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    • pp.62-67
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    • 1979
  • Ultraviolet microscopy of ultrathin sections of wood has proved to be one of the useful means for determining the lignin distribution in the various regions of the cell wall. Also, spectral approach and quantitative analysis of isolated compound middle lamella fraction from birch xylem have revealed that the lignin associated with the vessel secondary wall and middle lamella is composed predominantly of gualacylpropane units. Lignin deposited in the fiber and ray parenchyma secondary walls is composed mostly of syringylpropane units. The middle lamella lignin around fibers and ray cells contains both guaiacyl and syringyl propane quits. On the basis of the results above, this research was carried out to clarify the origin of milled wood lignin (MWL) by analysing the chemical characteristics of ML MWLs extracted at various milling stages. The amount of phenolic hydroxyl-, ${\alpha}$-carbonyl-, and methoxyl-group in the MWL's increases the milling time. And progressive mining contributes to the merease of ratio of syringylaldehyde to vanillin(S/V ratio) after nitrobenzene oxidation of MWL. Accordingly, It could be concluded that milled wood lignin extracted at the initial milling stage derives from compound middle lamella region of cell wall, whereas, with progressive milling, lignin of secondary wall of fiber is introduced gradually to milled wood lignin. These results are suggesting that heterogeneous chemical structure of lignins in hardwood exists. Although milled wood lignin at the initial stage seems to have lower molecular weight in comparison with milled wood lignin extracted at final milling stage from the result of Gel-filtration curves, further study would be required on molecular weight distribution of milled wood lignin in future.

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A Systematic Classification of Korean Fagaceae by the Pollen (화분(花粉)에 의한 한국산(韓國產) 참나무과(科) 계통분류(系統分類))

  • Park, Seung Young
    • Journal of Korean Society of Forest Science
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    • v.80 no.2
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    • pp.151-161
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    • 1991
  • I tried to specify the taxa of Fagaceae in Korea by the character of their pollen grains. The light microscope(LM) and the Scanning electron microscope(SEM) were used to examine the pollen grains of 19 taxa, 5 genera. The result are as follows. 1. The pollen of Fagaceae in Korea could be grouped into four types and 4 subtypes. 1) Fagus type 2) Castanea type 3) Lithocarpus, Castanopsis type 4) Quercus type (1) Cyclobalanopsis subtype (2) Prinus subtype (3) Dentatae subtype (4) Cerris subtype. 2. The morphology of the granula on the pollen of Quercus was closely related to the differantiation of the shape of the cup scales. 1) The uniformity of branching granula on the pollen grain surface corresponds to the morphological features of the concentric arrangement of cup scales. 2) The morphological features of the pollen grain surface intermingled with large or small granula, simple-granula and tuber granula which have small points of circular prominence, corresponded to those of short cup scales. 3) The morphological features of the polllen grain surface intermingled with large or small granula, simple-granula and tuber granula with an apex of amoeba type corresponded to those of Q. dentata Thunb, with thin, fine and long cup scales. 4) The morphological features of the pollen grain surface intermingled with large of small granula of with only simple-granula, corresponded to those of Q. acutissima carr. with thick, fine and long cup scales. 3. The result of cluster analysis by coding the sculpture pattern of the pollen grain surface, the existence and nonexistence of surface perforate, the grain size and granula type were coincident with the system of classification of plants and showed an intimated relationship even under th level of species.

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Classification and Analysis of Vegetation for a Multiple-purpose Management of Forest -Centering around Dong Hwa Sa Area on Mt. Pal Gong- (삼림(森林)의 다목적(多目的) 경영(經營)을 위한 식생(植生)의 분류(分類)와 분석(分析) -팔공산(八公山) 동화사 지역(地域)을 중심(中心)으로-)

  • Kim, Byeong Ku;Cho, Hyun Je;Lee, Byeong Cheon;Hong, Sung Cheon
    • Journal of Korean Society of Forest Science
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    • v.77 no.1
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    • pp.32-42
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    • 1988
  • This research was to establish the fundamental materials for the preservation and multiple-purpose management of forest vegetation of Dong Hwa Sa area located in the south facing slope of Mt. Pal-Gong. Analysis of forest vegetation of this area was studied by the method of Gentaro Toyohara, based on ZM School method and Pfister. The results obtained were summarized as follows. (1). Forest vegetation in this area divided into mountain forest and valley forest. (2). Mountain forest divided into A. Pinus densiflora community, B. Carpirtus laxiflora community, C. Quercus mongolica community. (3). Valley forest was formed mostly of Zelkova serrata community. (4). Piraus densiflora community divided into 1. Pines densiflora typical group, 2. Pines densiflora-Alnus hirsuta group, 3. Pines densiflora-Ilex macropoda group. (5). Quercus mongolica community divided into 1. Pinus densiflora-Carpinus cordata group, 2. Prunus sargentii-Hydrangea serrata for. acuminata group, (6). Zelkova serrata community divided into 1. Acer mono group, 2. Vine plant group. A vegetation analysis based on concepts and methods developed by Robert, D. Pfister and Gentaro Toyohara was considered to be effective on providing a guiding principle for a multiple-purpose management of forestry and a three-dimensional utilization of forest, but it is not easy for us to utilize such a analysis method because we are not rich in the materials of analysis of vegetation to our forest. Thus, It is necessary that we should collect much materials to various parts of forest in order that may utilize this method of analysis of vegetation.

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Studies on the Heteroplastic Grafting of Carpathian Walnut (Carpathian 호도(胡桃)나무의 종간품종간접목(種間品種間接木)에 관(關)한 연구(硏究))

  • Park, Kyo Soo
    • Journal of Korean Society of Forest Science
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    • v.66 no.1
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    • pp.95-108
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    • 1984
  • In order to see the effect of various factors on the success of grafting of walnut, a modified cleft grafting experiment has been conducted with Juglans sinensis Dode, J. regia (persian walnut), J. regiu (carpathian walnut), J. mandshurica, J. nigra and five cultivars of Carpathian walnut as "HANSEN", "METCALFE" "SCHOOL", "ILL CRATH", "LAKE" in a large green house equipped with automatic environmental control system in which temperature of the grafting bed at $28^{\circ}C$ and 85-100% for humidity during the period of January 1981-June 1983. As results of the experiments, the following facts were observed. 1) Hteroplastic grafting was proved to be more successful than homoplastic grafting with all five species tested among the J. regia (carpathian walnut), J. regia (persian walnut), J. sinensis, J. mondshurica, J. nigra. 2) It was interesting to notice that results hight survival of graft high as 99.33-100% with heteroplastic grafting when "Persian Walnut" and "Carpathian Walnut" was grafted on the stock of J. mandshurica and J. nigra. 3) A statistical significance of 5% Level was recognized in the above stocks among five species of homoplastic grafting with heteroplastic grafting and no significance among the scions. 4) The heteroplastic grafting when five cultivars of Carpathian Walnut as above as was grafted on the stock of Juglans nigra and J. mandshurica resulting high survival of graft as high as 85.33-100%. 5) As conclusion, the heteroplastic grafts of Carpathian Walnut and Persian Walnut was grafted on the stock of Juglans nigra and Jugdans mandshurica, the graft union, between stock and scion completed, in short period and was followed by a vigorous growth as well as "Cross Breeding", or hybrization, became apparent, with different desirable traits which could he used to cultivate a Later generation that combined these characteristics.

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Effect of Sweet Persimmon Wine on Alcoholic Fatty Livers in Rats (흰쥐에서 단감발효주가 알코올성 지방간 형성에 미치는 영향)

  • Nam, Kyung-Sook;Kim, Ju-Youn;Noh, Sang-K.;Park, Joong-Hyeop;Sung, Eon-Gi
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.11
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    • pp.1548-1555
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    • 2011
  • Persimmons are shown to contain high levels of phenolics. The present study was designed to investigate if a sweet persimmon wine (SPW) would affect the development of alcoholic fatty liver in rats. Initially, male Sprague-Dawley rats were housed singly in stainless steel wire-bottomed cages in a room of controlled temperature and lighting. The rats had free access to a nutritionally adequate AIN-93G diet and deionized water. After the acclimatization period, rats were weight-matched and assigned to the following three groups: two groups were fed 6.7% ethanol or the caloric equivalent of maltose-dextrin in a Lieber-DeCarli diet and the other group was fed the isocaloric Lieber-DeCarli diet containing SPW at the same ethanol level. All three groups were fed their respective diets for 6 weeks. Serum transaminase, cholesterol, and triglyceride levels were measured. Liver lipids and histology were assessed at 6 weeks. The total phenolic content and the antioxidant and free radical scavenging activities of SPW were determined. SPW significantly increased antioxidant and free radical scavenging activities. As markers of liver injury, serum alanine and aspartate transminases were markedly lowered by SPW at 6 weeks. SPW significantly reduced the serum levels of serum cholesterol and triglyceride compared to ethanol treatment. SPW delayed the development of an alcoholic fatty liver by reversing fat accumulation in the liver, as evidenced in histological observations. Taken together, SPW seems to protect the liver from becoming fatty by alleviating fatty liver symptoms and lowering hepatic and serum lipid levels. Such a protective effect of SPW appears to be in part due to its phenolics.

Extraction of Liberated Reducing Sugars from Rapeseed Cake via Acid and Alkali Treatments (산 및 알칼리 처리에 의한 유채박의 유리당 추출)

  • Jeong, Han-Seob;Kim, Ho-Yong;Ahn, Sye-Hee;Oh, Sei-Chang;Yang, In;Choi, In-Gyu
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.11
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    • pp.1575-1581
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    • 2011
  • Rapeseed cake, which is the organic waste remaining after rapeseed oil production, is readily available and considered an ecologically-friendly resource with very low cost and high dietary fiber content. This research was carried out for two reasons. First, it was done to analyze the liberated reducing sugar content of rapeseed cake. Second, it was done to investigate the effects on the sugar yield of the various concentrations of acidic and alkaline catalysts used for the hydrolysis of rapeseed cake and the concentrations of rapeseed cake in each catalyst. Several amounts of ground rapeseed cake, 0.5 g, 1 g, and 2 g, were put into 100 mL of catalysts such as sulfuric acid (0.5~2%), hydrochloric acid (0.5~2%), and sodium hydroxide (0.5~2%). Then they were hydrolyzed for 5 min at 121$^{\circ}C$. After hydrolysis, HPLC equipped with an RI detector was used to analyze liberated reducing sugars such as sucrose, glucose, galactose, fructose, and arabinose separated from rapeseed cake. The degradation rate of rapeseed cake was the highest in hydrochloric acid. As the catalyst concentrations used for hydrolysis of rapeseed cake increased, the degradation rate of rapeseed cake also significantly increased. Total reducing sugar content was the highest in hydrochloric acid, and it increased with the increase of catalyst concentrations. However, as the amount of rapeseed cake increased, the total reducing sugar content decreased, exceptionally sucrose in the case of sodium hydroxide.

Changes of Chlorophyll and SOD-like Activities of Chinese Chives Dehydrated at Different Heat Treatments (부추의 건조 온도 조건별 클로로필, Superoxide Dismutase 유사활성의 변화)

  • Kwak, Yeon-Ju;Kim, Jong-Sang
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.7
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    • pp.879-884
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    • 2009
  • Allium tuberosum Rotter (Liliaceae, Chinese chives) is a perennial herb of which leaves are used for food. This study investigated the effect of pretreatment on quality of dehydrated Chinese chives. Chinese chives was blanched at $80^{\circ}C$ for 20 sec, followed by drying at $70^{\circ}C$, $80^{\circ}C$, $100^{\circ}C$, or drying at $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$. Optimum drying temperature and time was $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$. These conditions were shortened time for dehydration and showed smaller decrease than others in Hunter color L, a, b. Dehydrated Chinese chives showed a constant decrease in greenness with storage, probably due to destruction of chlorophyll by light. In the measurement of Hunter color L, a, b, these conditions showed smaller decrease than others in Hunter color for 15 week storage. Chlorophyll content and SOD (superoxide dismutase)-like activity in that condition was higher than others. It was assumed that a phenolic compound that forms its thermostable activity. The fitness of drying models was conducted in order to explain reducing chlorophyll loss and SOD (superoxide dismutase)-like activity loss. Based upon the chlorophyll content, SOD-like activity, and retention of green color of the vegetable, optimum drying conditions was $100^{\circ}C$ for 30 min followed by $100^{\circ}C$ for 30 min and subsequent drying at $70^{\circ}C$, or $100^{\circ}C$ for 60 min and subsequent drying at $70^{\circ}C$.

Diversity, Spatial Distribution and Ecological Characteristics of Relict Forest Trees in South Korea (한국 산림유존목의 다양성, 공간 분포 및 생태 특성)

  • CHO, Hyun-Je;Lee, Cheol-Ho;Shin, Joon-Hwan;Bae, Kwan-Ho;Cho, Yong-Chan;Kim, Jun-Soo
    • Journal of Korean Society of Forest Science
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    • v.105 no.4
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    • pp.401-413
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    • 2016
  • Forest resources utilization and variable disturbance history have been affected the rarity and conservation value of forest relict trees, which served as habitat for forest biodiversity, important carbon stock and cultural role include human and natural history in South Korea. This study was conducted to establish the baseline data for forest resources conservation by clarifying species diversity, spatial distribution and ecological characteristics (individual and habitat) of forest relict trees (DBH > 300 cm) based on the data getting from mountain trail, high resolution aerial photos and field professionals and field survey. As results, 54 taxa (18 family 32 genus 48 species 1 subspecies 3 variety and 2 form) as about 22% of tree species in Korea was identified in the field. 837 individuals of forest relict trees were observed and the majority of the trees was in Pinaceae, deciduous Fagaceae and Rosaceae, which families are abundant in population diversity. High elevation area was important to relict trees as mean altitudinal distribution was 1,200 m a.s.l as likely affected by human activity gradients and mid-steep slope and North aspect was important environment for the trees remain. Many individuals exhibited 'damage larger branch' (55.6%) and consequent relatively lower mean canopy coverages (below 80%). Synthetically, present diversity and abundance of relict forest trees in South Korea were the result of complex process among climate variation, local weather and biological factors and the trees of big and old were estimated to important forest biodiversity elements. In the future, clarifying the role and function of relict trees in forest ecosystem, in- and ex- situ programmes for important trees and habitat, and activities for building the background of conservation policy such as "Guideline for identifying and measurement of forest relict trees".

Drought Stress Influences Photosynthesis and Water Relations Parameters of Synurus deltoides (건조스트레스가 수리취의 광합성 및 수분관련 특성에 미치는 영향)

  • Lee, Kyeong-Cheol;Lee, Hak Bong
    • Journal of Korean Society of Forest Science
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    • v.106 no.3
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    • pp.288-299
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    • 2017
  • This study was conducted to find out the influence of drought stress on physiological responses of Synurus deltoides. Drought stress was induced by withholding water for 25 days. Leaf water potentials were decreased of both predawn (${\Psi}_{pd}$) and mid-day (${\Psi}_{mid}$) with increasing drought stress, but water saturation dificit (WSD) was 7 times increased. ${\Psi}_{pd}-{\Psi}_{mid}$ showed the significant difference of 0.22~0.18 MPa in stressed before 10 days, and nonsignificant as treatment time became longer. A strong reduction of stomatal conductance ($gH_2O$) and stomatal transpiration rate (E) were observed after 15 days of drought stress Significant reductions of net apparent quantum yield (${\Phi}$) and maximum photosynthesis rate ($Pn_{max}$) were observed after 20 days of drought stress; However, water use efficiency (WUE) was shown the opposite trend. This implies that decrease of photosynthesis rate may be due to an inability to regulate water and $CO_2$ exchanged through the stomata. From JIP analysis, flux ratios (${\Psi}_O$ and ${\Phi}_{EO}$) and performance index on absorption basis ($PI_{ABS}$) were dramatically decreased withholding water after 15 days, which reflects the relative reduction of photosystem II activity. The leaf of S. deltoides showed osmotic adjustment of -0.35 MPa at full turgor and -0.40 MPa at zero turgor, and also cell-wall elastic adjustment of 9.4 MPa, indicating that S. deltoides tolerate drought stress through osmotic adjustment and cell-wall elastic adjustment. The degree of change in water relations parameters such as Vo/DW, Vt/DW decreased with increasing drought stress. This result showed that S. deltoides was exhibited a strong reduction of photosynthetic activity to approximately -0.93 MPa of predawn leaf water potential, and both of osmotic adjustment and cell-wall elastic adjustment in drought stress condition appears to be an important adaptation for restoration in this species.

Analysis of 2009 Revised Chemistry I Textbooks Based on STEAM Aspect (STEAM 관점에서 2009 개정 화학 I 교과서 분석)

  • Bok, Juri;Jang, Nak Han
    • Journal of Science Education
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    • v.36 no.2
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    • pp.381-393
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    • 2012
  • This study was analyzed that what kind of elements for STEAM, except scientific commonsense, are contained in 2009 revised chemistry textbooks I for high school students. So first, elements of STEAM in textbooks were examined by following three sections; by publishing company, each unit and area of textbook. For reference, new sub-elements of STEAM were set because existing elements of STEAM is incongruent with current textbooks. As a result, most chemistry textbooks included elements of STEAM properly for inter-related learning with the other fields. Every textbook had its unique learning methods for utilizing elements of STEAM and they were unified as one way. Depending on textbooks, learning methods were little bit different from the others. Also, detailed elements of STEAM contained in textbooks were classified just 14 types. And they were even focused on a few elements according to sort of textbook. Thus, it seemed that there was a certain limitation of current education of STEAM in chemistry Field. By the unit, according to the curriculum, contained elements of STEAM were different. Almost all elements of STEAM were located in I section. Consequently, it is difficult to include elements of STEAM if mathematics or history were not existed in curriculum. Lastly, by the area, most of all elements of STEAM were included in reference section. Almost all elements of STEAM were focused on art and culture. Thus, STEAM was used for utilization about chemical knowledge in substance. Otherwise, convergence training for approach method was not enough in chemical knowledge.

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