• 한국가구학회지
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• 제18권2호
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• pp.106-110
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• 2007

This study was performed to find potentialities of the leaves of gingko tree (Gingko biloba L.) as a raw material for particleboard (PB) manufacturing. Various amounts of the leaves were mixed with wasted wood particles to manufacture PB. Physical and mechanical properties, such as density, internal bond (IB) strength, and modulus of rupture (MOR) of manufactured PB were not much different from those of the control board. Formaldehyde emission values decreased with increasing the amount of leaves. Especially, the formaldehyde emission of PB made with 5 percent of leaves was decreased to 1.31 mg/l, which is about 36% lower emission than that of the control. From these results, the leaves of gingko tree may be considered as an additive of lowering formaldehyde emission in a functional PB manufacturing process.

• Journal of Forest and Environmental Science
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• 제37권2호
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• pp.154-162
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• 2021

Blueberry, which produces phenolic compounds, is one of the most popular fruits in Korea. During a survey on blueberry diseases, 16 Colletotrichum isolates were obtained from blueberry leaves in Chuncheon and Gosung, Kangwon province, Korea. Using morphological and molecular analyses, the isolates were identified as Colletotrichum aenigma, C. fioriniae, C. fructicola, C. gloeosporioides, and C. nymphaeae. C. gloeosporioides was the most frequently isolated (11 isolates), and only one or two isolates of the other species were found. After inoculation with all isolates, those leaves and fruits with wounds easily developed anthracnose; whereas, fruits without wounds became infected but leaves without wounds were infected by only two of C. gloeosporioides. Typically, around seven fungicidal agents are used to control anthracnose on blueberries in Korea. Fluzinam and prochloraz manganese complex strongly (over than 80%) inhibited the growth of all Colletotrichum species, while dithianon and mancozeb only weakly (about 80% or less) inhibited their growth.

• Asian-Australasian Journal of Animal Sciences
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• 제19권8호
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• pp.1134-1138
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• 2006

Forest tree leaves (12 different species) of semi hilly arid region of Punjab State were collected at 30-day interval throughout the year to assess the seasonal variations in tannin profile. Tannins were extracted and fractionated from fat free samples and data were analyzed statistically by $12{\times}12$ factorial design. The leaves of Anogeissus latifolia had the highest (p<0.05) concentration of total phenols (17.4%), net (15.9%) and hydrolysable (16.9%) tannins, followed by leaves of Acacia nilotica. Majority of the tree leaves selected had moderate levels (2-5%) of net tannins. Leaves of Carrisa had the highest (p<0.05) concentration of condensed tannins (CT), whereas the leaves of Anogeissus had the lowest (p<0.05) concentration of condensed tannins. The protein precipitable phenols (PPP) corresponded well with the net tannin content present in different tree leaves. Seasonal variation data revealed that in summer, net tannins and PPP decline in leaves of Bauhinia and Zizyphus whereas the net tannin content of Anogeissus and that of Carrisa increased during summer. The CT and PPP content in the leaves of Pheonix, Leucaena, Zizyphus and Ougenia increased in winter till spring season. Tree leaves generally had higher concentration of HT during summer months. It was concluded that leaves of leaves of A. nilotica, A. latifolia and L. leucocephala could serve as an excellent alternate feed stuffs for ruminants. However, leaves of Phoenix, Carrisa, Bauhinia and Dodonea should be avoided.

• Asian-Australasian Journal of Animal Sciences
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• 제17권6호
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• pp.777-783
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• 2004

Samples of 13 species of forest tree leaves fed to livestock in the semi-hilly arid zone of Punjab State in India were collected at 30 d interval for 12 months, in order to assess their nutritional worth for livestock. The ground samples were pooled for 4 different seasons viz. dry hot, hot humid, fall and winter. The chemical composition irrespective of the season revealed that CP content varied between 8.9 (Carrisa) to 22.0% (Leucaena). Globulin was the major protein fraction in most of the leaves. The lowest concentration of cell wall constituents was observed in Morus alba and Grewea. The leaves in general became fiberous and lignified during winter and fall as compared to summer season. The leaves of Grewea, Morus alba, Leucaena, Carrisa and Acacia were rich in Ca, P and most of the trace elements. The total phenolics ranged between 1.88% (Azardirachta) to 15.82% (Acacia). The leaves of Acacia had the highest concentration of hydrolysable tannins (14.6%) whereas that of Carrisa had that of condensed tannins (5.9%). The condensed tannins (more than 3%) were negatively correlated to the digestibility of dry matter (DM), neutral detergent fiber (NDF) and crude protein (CP). The digestion kinetic parameters for DM, NDF and CP revealed that leaves of Morus alba, Zizyphus and Ehretia had highest insoluble but potentially degradable fraction. The minimum rumen fill values also revealed that leaves of Grewea, Azardirachta, Morus, Ehretia and Leucaena had great potential for voluntary DM intake. The leaves of Ougeinia, Malha, Dodenia and Carrisa had significantly higher rumen fill value indicating poor potential for voluntary DM intake. Season did not have any significant impact on digestion kinetic parameters except that most of the leaves had low potentially degradable fraction, which was degraded at slow rate during winter. It was concluded that the leaves of Morus, Ehretia, Grewea and Leucaena had great potential as livestock feed, while feeding of Ougeinia, Malha and Dodonea leaves should be avoided.

• Journal of the Korean Wood Science and Technology
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• 제43권5호
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• pp.558-565
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• 2015

Katsura tree (Cercidiphyllum japonicum Sieb. Et Zucc) leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. The EtOAc fraction was chromatographed on a Sephadex LH-20 column with various aqueous MeOH eluting solvents and finally treated with acetone-$H_2O$ (7:3, v/v) to isolate a gallotannin. According to the NMR analysis, including HSQC and HMBC, and with the comparison of authentic literature data, the isolate was elucidated as 6-m-digalloyl-1,2,3,4-tetra-O-galloyl ${\beta}$-D-(+)-glucose, one of hydrolyzable tannins and one of gallotannins. The compound was only gallotannin which was firstly isolated from the extracts of Katsura tree leaves, and has not been reported before in domestic tree sources.

• 임산에너지
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• 제22권3호
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• pp.29-36
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• 2003

본 논문은 중국 장백산 북사면의 5가지 산림 군집에서 우세목의 잎 내 질소 환원 효소의 활성도를 보다 개량된 방법을 적용하여 측정 분석한 내용을 다루었다. 질소 환원 효소의 활성도는 수목의 내음성과 연관이 깊은 것으로 파악되어, 양수일수록 질소 환원 효소의 활성도가 높은 것으로 측정되었다. 또한 질소 환원 효소의 활성도는 산림내의 수직적 구조와 생태적 입지 조건과 연관이 깊은 것으로 나타났다. 질소 환원 효소의 활성도가 높은 수종들은 생장이 빠르고 생산력이 높은 것으로 판단된다.

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.270-280
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• 2017

Selection of superior phenotypes of fruit trees and products based on established criteria by local people is a prerequisite for future species domestication and conservation. Thus the study objective was to identify the local people's perceptions and preferences on baobab trees and products. A sample of 142 respondents was randomly selected using structured interviews in Blue Nile and North Kordofan, Sudan in 2013. Descriptive analysis was employed using SPSS and Excel programs. The study results indicated that local people use the morphological characteristics of the tree (leaves, fruits, seeds, kernels and bark) to differentiate individual trees. Based on the perceptions, local people recorded trees with delicious leaves, white pulp color, big fruit size and mature capsule size, and high pulp yield as criteria for differentiating between baobab trees in the study areas. In contrast, the undesirable traits were connected to trees with acidic pulp, slimy pulp, bitter leaves, and low pulp yield. The study concluded that the ethnobotanical knowledge of the baobab tree and its products may play an important role in tree domestication and improvement in Sudan. However, further research on tree genetics is needed to complement the ethnobotanical knowledge for baobab resources domestication and conservation.

• 임산에너지
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• 제25권2호
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• pp.28-33
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• 2006

본 연구에서는 대기오염에 대한 저항성과 내충성, 항균성 등이 강하여 가로수로 많이 심어진 은행나무에 있어서, 그 잎의 파티클보드 제조 원료로서의 가능성을 모색하고자 하였다. 이를 위해 은행나무 잎을 분쇄한 다음 목재 파티클에 소량 혼합하여 파티클보드를 제조하였다. 은행나무 잎을 혼합하여 제조한 파티클보드의 물리, 기계적 성질을 조사하고 포름알데히드 방출량의 저감효과에 대해 검토하였다. 목재 파티클에 대하여 은행나무 잎을 $1{\sim}5%$ 첨가하여 제조한 파티클보드는 은행나무 잎을 첨가하지 않은 대조구에 비해 밀도, 함수율, 흡수두께팽창률 등 물리적 성질과 휨강도, 박리강도와 같은 기계적 성질은 크게 감소하지 않았으며 모두 KS 파티클보드의 기준을 만족하였다. 은행나무 잎의 혼합량에 따라 포름알데히드 방출량은 점차 감소하였으며, 특히 은행나무 잎이 3% 첨가된 파티클보드의 포름알데히드 방출량은 $2.81mg/{\ell}$에서 $1.66mg/{\ell}$로 대조구에 비해 약 40% 감소하였다. 은행나무 잎이 지닌 고유한 항균성에 덧붙여 본 연구로부터 얻어진 결과는 낙엽으로 폐기되는 은행나무 잎을 원료로 포름알데히드 방출량이 낮은 기능성 파티클보드를 제조할 수 있다는 새로운 사실을 보여주고 있다.

• Journal of the Korean Wood Science and Technology
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• 제49권5호
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• pp.482-490
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• 2021

This research was conducted to analyze the sound absorption effect of air-dried leaves from two evergreen tree species found in Korea's warm-temperate and subtropical regions. As eco-friendly sound absorption materials, Dendropanax morbiferusa, and Fatsia japonica leaves were prepared in three specimen units sizes 0.5 × 0.5 cm², 1.0 × 1.0 cm², and 2.0 × 2.0 cm², and each of them was formed at a thickness of 1.00 cm, 1.75 cm, and 2.50 cm. The measured sound absorption coefficients (SAC) for 18 conditions were comparatively analyzed in this study. The SAC of both tree species was significantly improved by increasing the dried leaf layer thickness. These results showed a more consistent and distinct trend for both tree species under the condition of 0.5 cm² in dried leaf size compared to other leaf specimen sizes. However, as the thickness increased, the difference in sound absorption effect according to the leaf size tends to decrease overall. In the case of D. morbiferus, there was no significant difference in SAC based on leaf size under the condition of 2.5 cm thickness (p < 0.05). The highest mean SAC was found in a 2.5 cm thick condition with a leaf size of 0.5 × 0.5 cm², 0.549 for D. morbiferusa, and 0.594 for F. japonica, respectively.

• The Korean Journal of Ecology
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• 제14권4호
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• pp.371-377
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• 1991

Some morphological characteristics were investigated on the leaves of quercus aliena, hypostomatous species, and lespedeza cyrtobotrya, amphistomatous species, that appeared dominantly on the rock faces in mt.pukhan, mt surak and mt. pulam near seoul. These characteristics were compared with those of normal sites rock faces. All two species growing on the rock faces had thickened leaves with well developed upper epidermis and palisade tissue. Quercus aliena growing on the rock faces showed the leaves with double layer of palisade cells and more regularly arranged spongy parenchyma cells to the lower epidermis. In the case of lespedeza cyrtobotrya, narrower and more lengthened palisade cells and smaller air gaps between the sponge parenchyma cells were observed on the rock faces than those growing in the normal sites. The stomater frequency of the lower epidermis of the tree leaves growing on the rock faces is higher thanthose of normal sites. However, the mean total stomata number of the tree leaves growing on the rock faces are fewer. Most of the morphological characteristics investigated indicate that the plants on the rock faces havesmaller coefficient of variation than those of the normal sites.