• 한국산림과학회지
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• 제88권1호
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• pp.18-30
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• 1999

이 연구는 우리 나라 주요(主要) 낙엽(落葉) 활엽수(闊葉樹) 21종(種)에 대하여 줄기, 가지, 분지부(分技部)와 정단부(頂端部) 1년생 주간(主幹)과 측지(側枝) 등의 leaf specific conductivity(LSC)를 측정하여 수분통도성(水分通導性)의 배치구조(hydraulic architecture)를 수종별로 비교하였다. 고로쇠나무, 복자기, 박달나무, 물푸레나무와 느티나무를 제외한 활엽수종의 LSC 값은 줄기가 가지보다 컸으며, 분지부(分技部)는 가장 작은 값을 나타냈다. 특히 분지부(分技部)에 있어서 LSC값의 급격한 감소는 모든 수종에서 나타난 공통적인 특징이다. 산공재 수종에서는 자작나무, 피나무, 층층나무, 박달나무가 다른 수종에 비하여 높은 LSC를 나타냈으며, 복자기는 가장 낮은 LSC를 나타내는 수종이었다. 환공재 수종에서는 다릅나무, 참오동나무, 갈참나무, 졸참나무의 LSC가 높았으며, 느릅나무가 가장 낮은 LSC를 나타냈다. 복자기, 층층나무, 들메나무, 신갈나무와 느티나무에 있어서 정단부(頂端部) 1년생 주간(主幹) 및 측지(側枝)의 LSC값은 주간이 최소 $22{\mu}{\ell}/g$, 최대 $139{\mu}{\ell}/g$ 이고, 측지가 최소 $11{\mu}{\ell}/g$, 최대 $73{\mu}{\ell}/g$의 범위를 보였으며, 정단주간(頂端主幹)(leaders)이 정단측지(頂端側技)(adjacent laterals)보다 평균 2배 이상, 최대 5배 정도로 크게 나타나, 정단주간은 정단측지보다 수력적(水力的) 우세(優勢)(hydraulic dominance)를 보였다.

• 한국가구학회지
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• 제29권1호
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• pp.1-7
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• 2018

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Metasequoia glyptostroboides, diffuse-porous wood Anthocephalus cadamba and ring-porouswood Fraxinus rhynchophylla. In radial direction, ray cells and in longitudinal direction, tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of Metasequoia glyptostroboides was found the highest among all cells considered in Anthocephalus cadamba and Fraxinus rhynchophylla In radial direction, ray parenchyma of Metasequoia glyptostroboides was found the highest depth and the one of Fraxinus rhynchophylla was the lowest. The solution was penetrated lowest depth in the wood fiber of Fraxinus rhynchophylla. The large vessel of Fraxinus rhynchophylla was found the lowest depth among the vessels. The solutin was penetrated to the wood fiber of Anthocephalus cadamba higher than the one of Fraxinus rhynchophylla.

• 펄프종이기술
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• 제42권1호
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• pp.7-12
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• 2010

Morphological characteristics of hemp fiber were investigated using a light microscope in order to provide fundamental data for the use of hemp as a papermaking law material. Phloem of hemp is composed of cortical parenchyma cells and bast fiber with thick walls while xylem is composed of vessel, wood fiber and ray parenchyma cells. Also there are solitary pore and radial pore multiple which exist in diffuse porous pattern. Ray cells consist of uniseriate rays and thin walled ray parenchyma cells. Wood fibers are composed of three types: a large diameter fiber with longer length; a large diameter fiber with shorter length; a small diameter fiber with medium length. Vessel elements are composed of: a medium length one; a longer length one; the one whose both end walls have ligules or tails. Parenchyma cells in xylem and pit parenchyma cells have completely different size and shape. For bast fiber, the average length is about 4.4 mm and the width is about $30.5\;{\mu}m$; for vessel element, $600.0\;{\mu}m$ in length and $493.6\;{\mu}m$ in width; for wood fiber, $1000\;{\mu}m$ and $38.9\;{\mu}m$; for parenchyma cell, $50\;{\mu}m$ and $26.4\;{\mu}m$.

• 박물관보존과학
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• 제9권
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• pp.95-104
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• 2008

광주 신창동 유적에서 출토된 목제 유물에 대해 수종분석 37점, 칠분석 3점등총 40점에 대하여 분석하였다. 결과 목제품에 사용된 수종은 상수리나무류, 벚나무류, 살구나무류, 오리나무류, 단풍나무류, 버드나무류, 사시나무류 등으로 총 7종이 식별되었으며, 특히 칠기와 접시 같은 생활용품의 경우에는 모두 산공재 수종을 사용하였다. 칠도막 분석 결과 유공칠기와 통형칠기 동체부 5는 칠한 횟수에서 차이가 있지만 밑칠을 칠한 후 맨 상층에 흑색안료와 칠을 혼합하여 칠하였으며, 5절판은 토분과 흑색안료를 칠과 혼합하여 밑칠을 한 후에 상층에 흑색안료를 혼합한 칠을 칠한 것으로 확인되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.669-669
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• 2013

Hierarchical N doped TiO2 nanostructured catalyst with micro, meso and macro porosity have been synthesized by a facile self-formation route using ammonia and titanium isopropoxide precursor. The samples were calcined in different calcination temperature ranging from $300^{\circ}C$ to $800^{\circ}C$ at slow heating rate ($5^{\circ}C$/min) and designated as NHPT-300 to NHPT-800. $TiO_2$ nanostructured catalyst have been characterized by physico-chemical and spectroscopy methods to explore the structural, electronic and optical properties. UV-Vis diffuse reflectance spectra confirmed the red shift and band gap narrowing due to the doping of N species in TiO2 nanoporous catalyst. Hierarchical macro porosity with fibrous channel patterning was observed (confirmed from FESEM) and well preserved even after calcination at $800^{\circ}C$, indicating the thermal stability. BET results showed that micro and mesoporosity was lost after $500^{\circ}C$ calcination. The photocatalytic activity has been evaluated for methanol oxidation to formaldehyde in visible light. The enhanced photocatalytic activity is attributed to combined synergetic effect of N doping for visible light absorption, micro and mesoporosity for increase of effective surface area and light harvestation, and hierarchical macroporous fibrous structure for multiple reflection and effective charge transfer.

• 한국가구학회지
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• 제28권1호
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• pp.88-93
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• 2017

A study was carried out to observe the 1% aqueous safranine solution flow speed in longitudinal and radial directions of softwood Larix kaempferi (Lamb.)Carriere, diffuse-porous wood Betula davurica Pall.. and ring-porouswood Castanea crenata S.etZ. In radial direction, ray cells and in longitudinal direction, tracheids, vessel and wood fiber were considered for the measurement of liquid penetration speed at less than 12% moisture contents (MC). The length, lumen diameter, pit diameter, end wall pit diameter and the numbers of end wall pits determined for the flow rate. The liquid flow in the those cells was captured via video and the capillary flow rate in the ones were measured. Vessel in hardwood species and tracheids in softwood was found to facilitate prime role in longitudinal penetration. Anatomical features like the length and diameter, end-wall pit numbers of ray parenchyma were found also responsible fluid flow differences. On the other hand, vessel and fiber structure affected the longitudinal flow of liquids. Therefore, the average liquid penetration depth in longitudinal tracheids of Larix kaempferi was found the highest among all cells considered in Betula davurica and Castanea crenata, In radial direction, ray parenchyma of Larix kaempferi was found the highest depth and the one of Betula davurica was the lowest. The solution was penetrated lowest depth in the wood fiber of Castanea crenata. The large vessel of Castanea crenata was found the lowest depth among the vessels. The solutin was penetrated to the wood fiber of Betula davurica higher than the one of Castanea crenata.

• Journal of the Korean Wood Science and Technology
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• 제44권3호
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• pp.295-301
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• 2016

본 연구는 4개 종자산지(Yugoslovia, ltaly, United Kingdom, Bulgaria)의 글로티노사오리나무(Alnus glutinosa)를 대상으로 목섬유 길이, 도관 길이 및 직경인 해부학적 성질을 조사하여, 이들의 종자산지 간 및 생장속도와의 관계를 규명하였다. 글로티노사오리나무는 산공재, 계단상천공, 교호상벽공으로 나타났다. 접선단면에서 방사조직 높이는 9~11, 횡단면에서 방사조직 수는 16~26개로 나타났다. 산지 간의 목섬유 길이, 도관 길이 및 직경에서 만재부에서는 차이가 없었고, 조재부에서는 차이가 있는 것으로 나타났다. 3개 산지는 생장이 좋을수록 만재부의 목섬유 및 도관 길이가 짧아지는 것으로 나타났으나, 유고슬로비아산은 생장이 좋으면서 목섬유 및 도관길이도 긴 것으로 나타났다.

• 한국세라믹학회지
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• 제24권1호
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• pp.77-85
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• 1987

Hardened cement paste is mainly affected by corrosion of sulphate and chlorine ions in sea water. In this investigation, many specimens were made with the cement clinker minerals such as C3S, C3A, C4AF and their mixture according to cement composition added various blending materials. After the specimens were immersed in 4% MgSO4 and MgCl2 solutions, the product of reaction, the microstructure of specimen and Ca+2 ion leached in the solution were studied. The formation of Ca(OH)2 in the specimen of C3S is reduced relatively by adding pozzolanic admixtures. The chlorine ion is easily diffuse into the C3S specimen and produced CaCl2 compound, and it makes the specimen porous by leaching out itself into the solution. The specimen of C3A, C4AF are broken down by expanding reaction of ettringite and gypsum compound produced in the MgSO4 solution. At a later period, the ettringite is transformed into gypsum and 5MgO.2Al2O3·15H2O. The C3A in the MgCl2 solution combines chlorine ion to form Friedel's salt and prevents the diffusion reaction of chlorine ion into the specimen. Granulated slag shows inferior effect on the resistance of the specimen in MgSO4 solution by forming ettringite and gypsum, but good result in MgCl2 solution. Pozzolanic materials, on the whole, offer noticable effect on the resistance of the specimen in both solutions.

• Journal of the Korean Wood Science and Technology
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• 제51권5호
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• pp.410-418
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• 2023

In this study, the combustion characteristics of the Tulip tree, which is the representative broad-leaved afforestation tree in Korea, were analyzed. The flame retardant performance of the Tulip tree was analyzed by analyzing combustion characteristics on a total of three test samples; flame retardant treated, both flame retardant and oil stain-treated, and untreated. Then the flame retardance grade was classified for each of them. According to the result, test samples showed the strongest flame retardance were in order of flame retardant treated (C), both flame retardant and oil stain-treated (B), and untreated (A). As a result of analyzing the total heat emission and maximum heat emission rates, which is the evaluation standard for interior materials of Korean domestic buildings, test samples with flame retardant treat or flame retardant and oil stain treat were qualified for the flame-retardant standard. Both flame retardant and oil stain-treated samples showed higher total heat release (THR) and heat release rate compared to flame retardant-treated samples as the oil causes combustion with oxygen. On the other hand, they didn't qualify the THR in Quasi-non-combustible standards. To determine the correlation between the physical and combustion characteristics of wood, the combustion characteristics of other diffuse porous wood species, with which the Tulip tree is affiliated were analyzed, and noticed that the characteristic correlates with the density and quantity of wood. The results of this study are expected to be used as basic information on the combustion characteristics of the Tulip tree.

• Journal of the Korean Wood Science and Technology
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• 제40권4호
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• pp.244-256
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• 2012

본 연구에서는 인도네시아의 목재자원 중 새로운 유망 목재자원을 개발하고 최근 주요 조림 수종들의 효율적 이용을 위한 기초자료를 수집하기 위해 인도네시아산 10수종의 해부학적 특성을 조사하였다. 모든 수종은 산공재로써 고립관공, 방사복합관공이 관찰되었는데, Mangium에서는 위의 특성과 더불어 접선복합관공이 관찰되었다. 접선방향의 관공 직경은 Jeunjing과 Nangka를 제외한 전 수종에서 방사방향보다 큰 값을 보였다. 특히 Nangka는 공시수종 중 가장 큰 접선방향의 관공 직경을 보였다. 단위면적($mm^2$)당 관공의 수는 Mangium, Gandaria와 Kupa가 다른 수종보다 많았으며, 특히 Kupa가 가장 많게 나타났다. 유세포의 접선방향 폭은 Gmelina, Mangium, Kupa와 Mangga가 목섬유의 접선방향 폭보다 크게 나타났으며, 그 중 Mangium이 가장 큰 폭을 보였다. 이 밖의 6수종은 반대로 목섬유의 접선방향 폭이 유세포의 접선방향 폭보다 크게 나타났으나 Durian과 Nangka는 그 차이가 타 수종에 비해 미미했다. Gmelina, Jeunjing과 Rambutan은 평복세포로 이루어진 동성방사조직이, Gandaria는 평복세포와 단열의 직립세포로 구성된 이성방사조직이, Mangium, Durian, Jengkol, Kupa, Mangga와 Nangka는 평복세포와 약 1~2열의 직립세포로 구성된 형태의 이성방사조직이 관찰되었다. Durian, Gandaria, Jengkol, Jeunjing, Mangga, Rambutan은 결정을, Jeunjing과 Mangga는 실리카를 함유하는 특징을 나타냈다.