• Journal of the Korean Wood Science and Technology
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• 제37권6호
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• pp.546-555
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• 2009

이 연구에서는 목재의 효율적인 이용의 일환으로 스프루스 직교형적층재의 중층을 중밀도섬유판(medium density fiberboard, MDF), 파티클보드(particle board, PB) 및 배향성스트랜드보드(oriented strand board, OSB)의 3종류의 시판용 목질보드를 복합적층한 3층 목질계 복합적층재(패널)를 제작하여, 중층목질재료라미나의 구성엘리멘트가 복합적층재(패널)의 휨 강도성능에 미치는 영향을 조사하였다. 목질계 복합적층재의 휨 탄성계수는 중층에 배향성스트랜드보드(OSB)를 배열한 복합적층재에서 가장 높은 값을 나타내었고, 중밀도섬유판(MDF)을 중층에 배열한 복합적층재에서 가장 낮은 값을 나타내었다. 이 값은 중층에 섬유직각방향라미나를 배열한 다양한 종류의 직교형적층재 보다 높은 값을 나타내는 것이 확인되었다. 표층이 스프루스 섬유직각방향으로 된 복합적층재의 휨 탄성계수 예측치는 실측치와 비슷한 값을 나타내었으나, 표층이 스프루스 섬유방향으로 된 복합적층재의 휨 탄성계수 예측치는 실측치보다 높은 값을 나타내었다. 복합적층재의 휨 강도는 배향성스트랜드보드(OSB)를 중층에 배열한 타입에서 가장 높은 값을 나타내었고, 파티클보드(PB)를 중층에 배열한 타입에서 가장 낮은 값을 나타내어 휨 탄성계수와 약간 차이를 나타내었다. 복합적층에 의해, 복합적층재의 휨강도 성능의 이방성은 스프루스소재의 그것에 비해 현저히 감소하였고, 보드상호간의 강도성능의 차이도 현저히 감소하는 것이 확인되었다.

• 공업화학
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• 제32권2호
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• pp.197-204
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• 2021

본 연구는 건축용 자재인 목재 및 플라스틱의 연기 위험성 평가에 대하여 새로 고안된 연기성능지수-V (smoke performance index-V, SPI-V), 연기성장지수-V (smoke growth index-V, SGI-V), 연기위험성지수-VI (smoke risk index-VI, SRI-VI)를 중심으로 조사하였다. 시험편은 가문비나무, 나왕, polymethylmethacrylate (PMMA), polycarbonate (PC)를 사용하였다. 연기 특성은 콘칼로리미터(ISO 5660-1) 장비를 사용하여 시험편에 대하여 측정하였다. 연소반응 후 측정된 연기성능지수-V는 PMMA를 기준으로 1.0~3.4로 나타났다. 연기성능지수-V에 의한 연기위험성은 PC, 가문비나무, 나왕과 PMMA 순서로 증가하였다. 나왕과 PMMA는 유사한 값으로 나타났다. 연기성장지수-V는 PMMA를 기준으로 1.0~9.2로 나타났다. 연기성장지수-V에 의한 연기위험성은 PMMA, PC, 가문비나무, 나왕의 순서로 증가하였다. 모든 시편의 CO 피크 발생속도는 0.0021~0.0067 g/s로 측정되었다. 결론적으로 연소가 용이한 물질은 연기성능지수-V가 낮고, 연기성장지수-V가 높기 때문에 화재로 인한 연기위험성이 높은 것으로 이해된다. 이는 총괄적으로 연기위험성지수-VI로 정리된다.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.191-195
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• 2006

Multivariate data analysis tools were used to improve the understanding of the wet end chemistry and white water system of the Papermill at NorskeCanada Crofton Division. Specifically, the analysis was aimed at identifying what variables were contributing to increased retention aid use and wet end instability. Several models were developed using data sets with up to 88 process variables and over 3000 observations. It was found that increased retention aid use was driven primarily by PCC and TMP usage as well as the addition of Alaskan White Spruce to the TMP furnish.

• 한국산림과학회지
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• 제81권2호
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• pp.177-182
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• 1992

미국 Maine 주 저지대 가문비나무-젓나무 경제림 지역의 spodosol 토양의 2개의 토심(O와 B층)에서 토양공기 $CO_2$ 농도를 측정하였다. $CO_2$ 농도 측정은 Draeger 직독(直讀) chromatography법과 가스주입기를 이용한 gas chromatography 법의 두 가지 방법을 사용하였다. 1991년 생육기 동안의 토양공기 $CO_2$ 농도(%)의 평균값은 Draeger법으로 측정된 O층의 0.11로부터 gas chromatography법으로 측정된 B층의 0.29사이의 분포를 보였다. B층과 O층 모두에서 Draeger법에 의한 토양공기 $CO_2$의 농도가 gas chromatography법으로 측정된 값보다 낮은 수치를 보였다. 두 방법에 의해 측정된 값들 상호간에는 두 층 모두에서 고도의 상관관계 (p<0.01)를 보였으며, 시간변화에 따른 변화 유형 역시 평행적인 관계를 보여 주었다. 토양공기 $CO_2$ 농도는 토양온도와 고도의 정의 상관관계를 보였는데 상관계수의 값은 선발된 측정방법 및 토층에 따라 0.13-0.32의 값을 나타냈다.

• 한국산림과학회지
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• 제97권2호
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• pp.187-195
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• 2008

Picea jezoensis (Sieb. et Zucc.) Carriere is one of the major and widespread components of the cold-temperate and boreal forests in Russian Far East, northeast China, Korea, and Japan. However, it is restricted to a highly fragmented range in South Korea with small populations. Mean expected heterozygosity $(H_e)$ based on 22 loci in 11 isozyme systems was 0.077 for four sampled populations that covered the whole distribution range of P. jezoensis in South Korea. This value is within the range reported for conifers, but it is very low compared to that of other spruce species as well as that of P. jezoensis populations in Russian Far East. Most populations had a slight excess of heterozygotes and the Wright's $F_{IS}$ (-0.019) was comparable to that previously reported for other spruce species. In all of the four populations, the Wilcoxon sign-rank test indicated no greater heterozygosity than that expected for populations at mutation-drift equilibrium, suggesting that the populations have not been bottlenecked recently. Despite a fragmented range and isolated populations, population differentiation was not high $(F_{ST}=0.047)$ and the number of migrants per generation was 5.09. Nei's genetic distances were also small $({\bar{D}}=0.005)$ but strongly related to geographic distances between populations, suggesting an Isolation by Distance. The northernmost isolate, Mt. Gyebang population was genetically distinct from the other three populations. Implications for the conservation of genetic variation of P. jezoensis in South Korea were discussed.

• 한국가구학회지
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• 제21권6호
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• pp.499-504
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• 2010

한국의 전통가옥인 한옥은 대각재와 원형목으로 만든다. 이들은 열기건조하면 심각한 결함이 발생하기 때문에 보통 수개월에서 1년까지 천연건조하는데 그래도 사용중 결함이 생긴다. 열처리기술을 이용하여 이들을 $170^{\circ}C$이상에서 건조하면서 건조결함을 조사하였다. 온도곡선은 모두 하나 또는 두개의 변곡점을 나타냈다. 표면에서 37.5mm 깊이지점이 $100^{\circ}C$에 도달하는데 걸리는 시간은 열처리온도 $170^{\circ}C$ 과 $190^{\circ}C$가 두 배의 차이를 나타냈다. 열처리 후에 $148mm{\Phi}$ 원형목에 내부할렬이 많이 발생한 것이 발견되었으나, 이에 빈해 표면할렬은 거의 닫혀 있었다. 이러한 표면할렬의 변화를 $300{\times}300mm$ 대각재의 사진을 통해 관찰하였다. 중공재와 무중공재의 건조시간을 비교하였더니 두 배의 차이를 나타냈다.

• 식물분류학회지
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• 제42권1호
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• pp.80-90
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• 2012

우리나라 미기록 태류식물 10 분류군을 발견하였다. 털이끼과의 털이끼 [Neotrichocolea bissetii (Mitt.) S. Hatt.]와 목걸이이끼과의 은목걸이이끼 [Calypogeia angusta Steph.], 겉게발이끼과의 바위겉게발이끼 [Cephaloziella massalongii K. Mller], 기발이끼과의 숲비늘이끼 [Harpanthus scutatus (F. Weber & D. Mohr) Spruce], 둥근망울이끼과의 보라망울이끼 [Plectocolea torticalyx (Steph.) S. Hatt.]는 지리산 중산리계곡, 한신계곡 및 천왕봉 부근에 자생하고 있었으며, 엄마이끼과의 새깃통꼴이끼 [Anastrophyllum michauxii (F. Weber) H. Buch], 엄마이끼과의 산중갈래잎이끼 [Lophozia excisa (Dicks.) Dumort.], 엄마이끼과의 계곡갈래잎이끼 [Lophozia lantratoviae Bakalin], 날개이끼과의 돌잔비늘이끼 [Mylia verrucosa Lindb.], 엄마이끼과의 바위엄마이끼 [Scapania sphaerifera H. Buch.]는 설악산 대청봉, 소청봉, 끝청 및 구곡담계곡 부근에 소수의 개체가 자생하고 있었다.

• Journal of the Korean Wood Science and Technology
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• 제35권5호
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• pp.7-15
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• 2007

To evaluate the durability of finger-jointed woods according to change of humidity conditions, four types of finger-jointed woods glued with different kinds of adhesives and finger pitches were made with Sitka spruce, and the effect of humidity conditions on creep performances was investigated. The shape of creep curves differed among humidity conditions, and the inclination of creep curves was greatest in 85%RH, and lowest in 65%RH. Their creep curves showed a linear behavior beyond approximately one hour, regardless of humidity conditions. The A values of the creep curves fitted to power law increased with increasing relative humidity, whereas the A' values were in order of 30 > 85 > 65%RH unlike the A values. The initial deformation increased with increasing relative humidity, whereas the creep deformation unlike the initial deformation was in order of 85 > 30 > 65%RH, and it was found that the creep deformation of finger-jointed woods indicated the smaller amount in air-dry moisture content rather than in a low moisture content less than 30%RH. Finger-jointed woods with 6.8 mm (L) pitch had the greater creep amount than in those with 4.4 mm (S) pitch in all humidity conditions. The difference of creep amount between both adhesives in all humidity conditions was small. Relative creep at 240 hr was greatest as 62.2~71.9% in 85%RH, and the values indicated 2.1~2.6 times that of 30%RH and 3.0~3.6 times that of 65%RH and were equal or slightly greater than that of solid spruce.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 1999년도 Pre-symposium of the 10th ISWPC Recent Advances in Paper Science and Technology
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• pp.254-258
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• 1999

The distribution of anionic groups in the fibers, the fines, the colloidal fraction and the dissolved fraction, respectively, of thermomechanical pulp (TMP) suspensions was determined and peroxide bleaching of spruce TMP were also studied. Spruce TMP was extracted with hexane, treated with alkali, or bleached with peroxide. Suspensions made at pH 5.5 were fractionated into long fibres, large fines, small fines, a colloidal fraction and a dissolved fraction. The charge of the fractions was determined using polyelectrolyte titration. To determined the origin of the charges, the contents of fatty acids, resin acids and acidic units in hemicelluloses in the different fractions were determined by has chromatography. Extraction of TMP with hexane prior to fractionation increased the measured charge of the fibres. The removal of the wood resin probably uncovered some carboxyl groups on the fibre surfaces, or improved th e penetration of polybrene into the pores of the fibres. The charge of the fines and the colloidal fraction was lower when the wood resin had been removed. Alkaline treatment of the TMP increased the charge of the fibres and fines, mainly because of demethylation of pectins. Alkaline treatment increased the charge also of the dissolved fraction, because of the release the charge also of the dissolved fraction, because of the release of pectic acids into the water phase. Alkaline peroxide bleaching further increased the charge of fibres and the dissolved fraction, most likely because of lignin oxidation. The charge of the colloidal fraction, consisting mainly of wood resin, was only slightly affected by alkaline treatment and peroxide bleaching. The anionic groups in TMP suspensions were mainly free uronic acids in the hemicelluloses. The contribution from the fatty and resin acids was substantial only for the colloidal fraction.

• Plant Biotechnology Reports
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• 제2권4호
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• pp.259-265
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• 2008

Picea koraiensis, called Korean spruce, is an evergreen tree and found mostly in northeast Asia. In this study, plant regeneration via somatic embryogenesis from open-pollinated immature zygotic embryos of nine geno-types of elite trees was established. Immature zygotic embryos were cultured onto RJW medium modified from 505 medium with $21.48{\mu}M$ NAA, $2.22{\mu}M$ BA, and $2.32{\mu}M$ KT. The average frequency for all nine genotypes was 74.2%. Embryogenic calluses of the nine genotypes of elite trees were subcultured on RJW basal medium containing $8.06{\mu}M$ NAA, $1.11{\mu}M$ BA, and $1.16{\mu}M$ kinetin. The calluses of three lines, $3^{\sharp}$, $9^{\sharp}$, and $2^{\sharp}$, were actively proliferated but others were not. Somatic embryogenesis was induced from the embryogenic callus in genotypes of $3^{\sharp}$, $9^{\sharp}$, and $2^{\sharp}$ on RJW medium with ABA and $60g\;l^{-1}$ sucrose. Cotyledonary somatic embryos were subjected to a drying process. The drying of embryos by uncapping the culture bottle for 5 days on a clean bench resulted in a high frequency of germination of somatic embryos (87% in RJW medium). However, plantlet conversion from germinated embryos was greatly reduced and the optimal medium for plant conversion was 1/2 WPM or 1/2 BMI medium. In conclusion, we have, for the first time, established a plant regeneration system via somatic embryogenesis in the Korean spruce, which can be applied for rapid micropropagation of elite trees.