• Title/Summary/Keyword: spruce

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Competitive Ability and Allelopathy of Ericaceous Plants as Potential Causes of Conifer Regeneration Failures (Ericaceous식물의 allelopathy와 경쟁력에 의한 침엽수 갱신 저해)

  • Mallik, A.U.
    • Journal of Korean Society of Forest Science
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    • v.84 no.3
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    • pp.394-405
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    • 1995
  • Certain ericaceous understory plants of temperate forests proliferate following forest clearcutting and fire. Rapid vegetative growth of these plants may affect conifer regeneration due to their strong competitive abilities and allelopathic properties. Planted conifers in these shrub-dominated habitats experience "growth check" which may result in a loss of productivity or in extreme cases total failure of forest regeneration. This growth check phenomenon is exemplified in Calluna Sitca spruce Scots pine ecosystems of western Europe, Kalmia black spruce ecosystem of eastern Canada and Gaultheria-cedar/hemlock ecosystem of the Pacific Northwest of the United States. Dynamics of Kalmia black spruce ecosystem following disturbance was used to explain the mechanism of conifer growth inhibition and their regeneration failure. It is argued that in addition to competition for nutrients, Kalmia allelopathy plays a major role in growth inhibition of black spruce. This conclusion is supported by the results of various field, laboratory and greenhouse experiments. Eight phenolic compounds were isolated and identified from the leaves of Kalmia angustifolia, four of which are known to be highly phyotoxic to black spruce. Methods of overcoming the allelopathic effects of Kalmia in order to enhance black spruce regeneration in Kalmia-dominated sites are discussed.

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Pyrolysis-Liquefaction of a Siberian Spruce Biomass (시베리아산 전나무 바이오매스의 열분해-액화반응)

  • Yoon, Sung-Wook
    • Journal of Hydrogen and New Energy
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    • v.19 no.5
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    • pp.430-438
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    • 2008
  • Siberian spruce, found in the northern temperature and boreal regions of the earth, is usable biomass as fuels. In this study, parameters of thermochemical degradation by pyrolysis-liquefaction reaction of siberian spruce such as the effect of reaction temperature, reaction time and degradation products and energy yields were investigated. The liquid products from pyrolysis-liquefaction of siberian spruce contained various kinds of cyclicketones, cresols, dimethyl phenols and benzenediols. Combustion heating value of liquid products from pyrolysis-liquefaction conversion processes was in the range of $7,650{\sim}7,800cal/g$. The energy yield in pyrolysis-liquefaction of siberian spruce was as high as 69.5% after 40min of reaction at $400^{\circ}C$. The liquid products from the thermochemical conversion of siberian spruce could be used as high octane value fuels and fuel additives.

Acetone Solvolysis of a Siberian Spruce Biomass (시베리아산 전나무 바이오매스의 아세톤 용매분해반응)

  • Yoon, Sung-Wook
    • Journal of Hydrogen and New Energy
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    • v.20 no.1
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    • pp.55-63
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    • 2009
  • In this study, thermochemical degradation by acetone solvolysis reaction of siberian spruce wood was investigated for a temperature range of $200{\sim}400^{\circ}C$. The liquid products by acetone solvolysis from siberian spruce wood produced various kinds of aliphatics, cyclic compounds and aromatics included phenols etc. Combustion heating value of liquid products by acetone solvolysis conversion processes was in the range of $8,010{\sim}8,180cal/g$. The energy yield in acetone solvolysis of siberian spruce wood was as high as 74.2% after 40min of reaction at $400^{\circ}C$. The liquid products from the thermochemical conversion of siberian spruce wood could be used as high-octane-value fuels and fuel additives.

Improving the Dimensional Stability of Spruce and Birch Boards by Heat-Treatment at 190 and $210^{\circ}C$

  • Kang, Ho-Yang
    • Journal of the Korea Furniture Society
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    • v.20 no.6
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    • pp.560-565
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    • 2009
  • It is known that heat treatment decreases the hygroscopicity of wood. Thus heat-treated wood is good for outdoor construction due to its improved dimensional stability. This study is to investigate the hygroscopicity and discoloration of spruce and birch boards heat-treated above $190^{\circ}C$. The equilibrium moisture contents (EMCs) at all relative humidities decreased with the increase of heat treatment temperature and/or time for both spruce and birch. It was revealed that heat-treatment temperature affected more on the hygroscopicity thaan heat-treatment time. The average basic densities decreased for the spruce specimens, but increased for the birch specimens with an increase of the treatment time and/or temperature. The same heat treatment condition (190-8) made the birch specimens darker than the spruce specimens.

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Studies on the Vibrational Modal Analysis of Solid Woods for the Violin Making - Part 1. Effect of Cutting Direction and Density on Resonant Frequency of Woods (바이올린용(用) 소재(素材)의 진동모드 해석(解析)에 관한 연구사 - 제1보. 절삭방향 및 밀도에 따른 공진 주파수의 변화)

  • Chung, Woo-Yang;Park, Sun-Haeng
    • Journal of the Korean Wood Science and Technology
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    • v.27 no.3
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    • pp.1-6
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    • 1999
  • European spruce and maple were to be estimated as raw material of violin family instruments with linear modal analysis to provide the information data for the design of their bodies. Wood specimens cut in different direction were excited by impact hammer to measure the resonant frequency with typical vibrational modes. In spite of lower density than maple, European spruce showed the excellent acoustical properties with higher resonant frequency. And edge-grained spruce had more even frequencies than flat-grained ones to be more acceptable as front plate of violin. Resonant frequency was positively correlated with wood density of each specimen and the coefficients of edge-grained specimens were higher than those of flat-grained specimens of both wood species.

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Influence of Temperature and Moisture on the Radial Growth of Scots Pine and Norway Spruce in Kaunas, Lithuania (Lithuania 의 Kaunas 지역 구주소나무와 독일가문비의 연륜생장에 대한 기온과 수분의 영향)

  • Karpavichus J.;J. Kairaitis;R.R. Yadav
    • The Korean Journal of Ecology
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    • v.19 no.4
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    • pp.285-294
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    • 1996
  • Ring-width chronologies of Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) from two experimental forest plots in Kaunas, Lithuania were developed to study tree growth-climate relationship in different geohydrological conditions using response function analysis. The tree ring-width chronologies of Scots pine ranged from 1883~1987 A.D. and 1864~1989 A.D., and Norway spruce 1838~1987 A.D. and 2870~1989 A.D., respectively. The response function analysis has vividly demonstrated that the growth of Scots pine is favoured by warm summer and Norway spruce by cool and moist summer. Spring temperature has shown direct relationship with tree growth of both the species. There also exists notable intraspecies analogies in growth responses except some minor differences.

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Origin of Milled Wood Lignin : An Immunocytochemical Approaches in Combination with Transmission Electron Microscopy (면역전현법(免疫電顯法)에 의한 마쇄(磨碎) 리그닌의 기원(起源)에 관한 연구(硏究))

  • Kim, Yoon-Soo;Koh, Hong-Bum
    • Journal of the Korean Wood Science and Technology
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    • v.24 no.1
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    • pp.68-74
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    • 1996
  • Present work was undertaken to investigate the origin of milled wood lignin(MWL) in the wood cell wall using immunocytochemical techniques, which can provide the information on the localization of specific antigens(MWL in the present study) to be examined. Spruce MWL dissolved in DMSO and emulsified with Freund adjuvant was injected directly into the mouse spleen. The animals were boostered at two-week intervals after the initial immunization. Blood samples were purified in standard procedures. The characteristics of antibodies against MWL were tested by indirect ELISA. Visualization of MWL was carried out using conventional indirect immunogold-labelling methods on the ultrathin sections of spruce wood. Immuno-TEM observations showed that the immunogold probes were selectively attached to secondary cell walls of spruce wood. The most intense labelling was frequently observed in the S2 layer. In contrast, gold labelling in the lignin-rich regions, such as middle lamella and cell corner was not found. The immuno-TEM provides an indication that spruce MWL originates from the S2 layer.

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Effect of specific gravity and annual ring width on the acoustical properties of European lumber used in violin making (유럽산 바이올린 용재의 비중과 년륜폭이 소재의 음향적 성질에 미치는 영향)

  • 정우양;홍병화
    • Journal of the Korea Furniture Society
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    • v.10 no.1
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    • pp.57-63
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    • 1999
  • This study was carried out to analyze the relationship between basic physical properties and acoustical characteristics of imported violin wood and to offer the information on raw material procurement and incoming-material quality control to domestic violin makers which have purchased most raw materials from European exporting countries at high expense. Equilibrium moisture content of European spruce with lower specific gravity after the prolonged storage was rather higher than that of European maple with higher specific gravity. The specific gravity of spruce increased with decreasing annual ring width, however, that of narrower annual ring. Increasement in specific gravity enhanced the dynamic Young's modulus of both wood species, but influenced the vibration energy loss by internal friction differently between two species. For dynamic MOE, qurater-sawn spruce was higher than the flat-sawn, but maple showed the reverse directional characteristics. Consequently, it would be well for violin makers to establish the standard for materials and quality control system to assure the quality of their violin products.

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Characteristics of Thermomechanical Pulps Made of Russian Spruce and Larix, and Myanmar Bamboo (러시아산 가문비와 낙엽송, 그리고 미얀마산 대나무로 제조한 열기계펄프 특성 연구)

  • Lee, Ji-Young;Kim, Chul-Hwan;Nam, Hyegeong;Park, Hyunghun;Kwon, Sol;Park, Dong-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.44 no.1
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    • pp.135-146
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    • 2016
  • Three fiber sources including Russian spruce (Picea jezoensis) and larix (Larix leptolepis), and Myanmar bamboo (Phyllostachys bambusoides) for thermomechanical pulp were explored to replace domestic pine (Pinus densiflora) pulp that has some limitations in an aspect of supply and pitch trouble. Thermomechanical pulps were manufactured under the identical condition, and then compared with their representative pulp properties and pulping process. Both Russian larix and Myanmar bamboo contained large amounts of extractives that would negatively affect mechanical pulping processes. Russian spruce showed the least contents in shives and pitch. Russian spruce and domestic pine reached an optimum freeness level within a short pulp processing time, which consumed less amount of refining energy compared to larix and bamboo. In particular, the spruce wood showed the highest brightness level which might lead to a less consumption of bleaching chemicals. It was expected that Russian spruce could be replaced with the domestic pine wood in respect of both pulping process and pulp quality.

Studies on the Vibrational Modal Analysis of Solid Woods for making the Violin - Part 2. The effects of coating materials on the resonant frequency of European spruce and maple

  • Chung, Woo-Yang;Park, Sun-Haeng
    • Journal of the Korea Furniture Society
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    • v.11 no.1
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    • pp.45-51
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    • 2000
  • It was thought that the stiffness of a coated specimen became lower than that of the solid wood because the stiffness of the dried film of coating material is lower than that of the solid wood. The authors were trying to compare the effect of lacquer varnish and rhus lacquer on the resonant frequency of the solid woods for the violin, spruce and maple. Vibration modal shape of coated specimens were same to those of solid woods, but the frequency became lower at each mode as were expected regardless of coat. frequency decrement of coated specimen was getting larger at upper mode in both European violin woods, however, rhus lacquer coated spruce specimens were less affected than lacquer varnish coated specimens.

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