• 펄프종이기술
• /
• 제41권4호
• /
• pp.1-7
• /
• 2009

One commercial Xuanji and five traditional paper which were made in south china were collected and its chemical, physical, optical properties were investigated and compared to those of Hanji. Extractives(cold, hot, 1% NaOH and Alcohol-benzene) of bamboo paper had higher contents compared with other papers. Strength properties had been highest Hanji, but had been lowest Xuanji 1 and 2. Brightness of all paper were decreased as following order; Xuanji, Hanji, Thai paper, bast paper 1, bast paper 2, Dongpa paper, bamboo paper.

• Journal of the Korean Wood Science and Technology
• /
• 제25권2호
• /
• pp.45-51
• /
• 1997

주목 잎을 채취하여 건조하고 아세톤-물 (7 : 3, v/v) 의 혼합액으로 추출한 후 에틸아세테이트 및 수용성 부분으로 분리하고 Sephadex-LH 20으로 충진한 칼럼을 이용하여 2개의 flavan 단량체와 2개의 후라보노이드 배당체를 단리하였다. 에틸아세테이트용성 추출물은 대부분 (+)-catechin 과 (-)-epicatechin으로 구성되어 있었으며 수용성 부분에서는 quercetin-3-0-arabinopyranosyl-($1"'{\rightarrow}6"$)-${\beta}$-D-glucoside와 quercetin-3-O-rutinoside 인 두 개의 탄수화물로 구성된 배당체를 분리하였으며 주목에서는 이들 화합물은 아직 보고된 바가 없다. 이들의 구조결정을 위하여 박층크로마토그래피를 실시하고 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 기존의 스펙트럼과 비교, 분석하여 정확한 구조를 규명하였다.

• Journal of the Korean Wood Science and Technology
• /
• 제25권2호
• /
• pp.81-87
• /
• 1997

일본잎갈나무잎을 채취하여 아세톤 : 물 (7 : 3, v/v) 의 혼합용액으로 추출한 후 에틸아세테이트용성 화합물과 수용성 화합물로 분리하였으며 Sephadex LH-20으로 충진한 칼럼을 사용하여 화합물을 단리 하였다. 단리 화합물을 확인하기 위하여 셀룰로오스 박층 크로마토그래피(TLC)를 실시한 후 자외선 램프 하에서 관찰하였다. 바닐린 발색제를 분무히여 정색반응을 조사하고 $R_r$ 값을 구하였다. 단리된 화합물들의 구조는 $^1H$-NMR과 $^{13}C$-NMR 스펙트럼을 이용하여 그 구조를 규명하였으며 에틸아세테이트용성 화합물에서는 (+)-catechin, (-)-epicatechin, kaempferol-O-arabinofuranoside와 kaempferol-3-O-arabinopyranoside, 수용성 화합물에서는 apigenin-8-C-rhamnosyl-($1"'{\rightarrow}2"$)-glucoside(2"-O-rhamnosylvitexin)을 단리 하였다.

• Journal of the Korean Wood Science and Technology
• /
• 제24권2호
• /
• pp.81-93
• /
• 1996

To elucidate the structure of procyanidin in Korean red pine (Pinus densiflora S. et Z.), bark, the extractives were extracted with acetone-water mixture(7:3, v/v) from inner bark of Korean red pine. The extracts separated three fractions which were extracted by liquid-liquid extraction. The extracting solvents were chloroform and ethyl acetate and water. The part of ethylacetate soluble was chromatographed by liquid chromatography. The ethylacetate soluble portion yielded four natural procyanidin dimers, two known epicatechin-($4{\beta}{\rightarrow}6$)-catechin, catechin-($4{\alpha}{\rightarrow}8$)-catechin and two unknown catechin-($4{\beta}{\rightarrow}6$)-catechin and conformational isomer of epicatechin-($4{\alpha}{\rightarrow}6$)-catechin. The additional catechins was also isolated. The structures of these procyanidins were elucidated by their $^{13}C$-NMR spectra.

• Journal of the Korean Wood Science and Technology
• /
• 제26권4호
• /
• pp.61-70
• /
• 1998

Xylem, bark and flower buds of Magnolia kobus DC. var. borealis Sarg. were extracted with ethanol. And then the ethanol extracts were fractionated with diethyl ether. The lignans structure of the diethyl ether fractions were determined by spectroscopic methods. The results are summarized as follows : 1. Three compounds, aschantinn(X-I), yangambin(X-II), (-)syringaresinol(X-III), tetrahydrofurofuranoid lignans were isolated from the xylem. 2. Five compounds were isolated from the bark. These are all tetrahydrofurofuranoid lignans, aschantin(B-I), yangambin(B-II), medioresinol(B-III), (+)syringaresinol(B-IV), and tetrahydrofuranoid, kobusinol B(B-V). 3. Three tetrahydrofurofuranoid lignans, kobusin(F-I), aschantin(F-II), yangambin(F-III) were isolated from the flower buds. 4. Isolated lignans from the each tissue were two types of tetrahydrofurofuran type and tetrahydrofuran type. 5. The tetrahydrofurofuranoid lignans were five compounds such as kobusin, aschantin, yangambin, medioresinol, and syringaresinol, while the tetrahydrofuranoid lignans was kobusinol B. 6. Most of these lignans were substituted with the methylenedioxy or methoxyl groups.

• Journal of the Korean Wood Science and Technology
• /
• 제25권3호
• /
• pp.8-15
• /
• 1997

The ultrasonic velocity and dynamic MOE of acetylated bamboos were investigated using PUNDIT, a transit time measuring device for longitudinal ultrasonic propagation. Bamboo specimens were boiled in acetic anhydride for 2, 4 and 6 hours, and the maximum average WPG (Weight Percentage Gain) of 19% was obtained at 6 hours. The volumes of acetylated bamboos increase with boiling time and WPG, while as WPG increases their oven-dry densities generally increase with a concave around 5% WPG. This oven-dry density pattern likely influences the trends of ultrasonic velocity and dynamic MOE. which generally decrease with a convex around 5% WPG. It is postulated that during boiling extractives in a bamboo move and aggregate at its surfaces transiently, resulting in the increase of ultrasonic velocity and dynamic MOE. To explain the fact that ultrasonic velocity varies with WPG a simple model was proposed and some ultrasonic properties of a transmitted wave were examined.

• Journal of the Korean Wood Science and Technology
• /
• 제10권3호
• /
• pp.166-166
• /
• 1982

This study has been made to make an observation regarding present status of the coal mine props which is desperately needed for coal production, despite of great shortage of the timber resources in this country, and investigate the effects of diffusion process on the decay resistances of the mine props as applied preservatives of Malenit and chromated zinc chloride. The results are as follows. 1. Present status of the coal mine props Total demand of coal mine props in the year of 1975 was approximately 456 thousand cubic meters. The main species used for mine props are conifer (mainly Pinus densiflora) and hardwood (mainly Quercus). Portions between them are half and half. With non fixed specification, wide varieties of timber in size and form are used. And volume of wood used per ton of coal production shows also wide range from 0.017 cubic meter to 0.03 cubic meter. 2. Decay resistance test a) The oven dry weight decreased between untreated specimen and treated specimen has not shown any significantly, although it has shown some differences in average values between them. It may be caused by the shorter length of the test. b) The strength of compression test between untreated specimen and treated specimen has also shown the same results as shown in case of weight decrease. Reasons assumed are the same. c) The amounts of the extractives in one percent of sodium hydroxide (NaOH) between untreated and treated specimen have shown the large value in case of untreated specimen than that of treated. 3. The economical benifit between untreated and treated wood when applied in field has seen better in long tenn base in case of treated wood, although the primary cost of treated wood add a little bit more cost than that of the untreated wood.

• 임산에너지
• /
• 제20권2호
• /
• pp.9-19
• /
• 2001

본 연구는 식품포장용 골판지에 사용되는 유기합성 구충제를 대체할 수 있는 천연 구충물질을 탐색하기 위하여 수목의 잎이나 수피 또는 목질부에서 화학성분을 추출하고 그 추출물에 대하여 화락곡나방 유충을 이용한 기피시험을 수행하였다. 아까시나무 목질부와 현사시나무, 수양버들 및 버드나무 수피, 그리고 주목과 비자나무의 잎을 채취하여 아세톤-물(7:3)의 흔합액으로 추출하고 hexane, CH₂Cl₂ ethylacetate(EtOAc)와 물로 분획하여 동결 건조한 후 Sephadex LH-20 칼럼에서 크로마토그래피를 수행하였으며 단리된 물질들은 NMR 및 MS 분석에 의하여 그 구조를 결정하였다. 각 수종의 EtOAc 또는 수용성 분획은 2% 또는 3% 농도로 인쇄용 잉크에 흔합되어 상업용 골판지에 인쇄하고 이를 기피시험을 위한 재료로 사용하였다. 아까시나무 EtOAc용성 분획에서는 robtin과 dihydrorobinetin이, 수용성 분획에서는 leucorobinetinidin이 단리되었으며 현 사시나무 수피의 EtOAc용성 분획은 (+)-catechin, naringenin, aromadendrin, eriodictyol, sakuranetin 및 그 배당체, taxifolin, neosaturanin, p-coumaric acid 및 salireposide 그리고 수용성 분획에서는 aesculin을 단리하였다. 버드나무 수피의 EtOAc용성 분획에서는 다량의 (+)-catechin 이외에 (+)-gallocatechin 및 p-coumaric acid가 분리되었으며 수양버들 수피의 EtOAc용성 분획에서도 (+)-catechin, (+)-gallocatechin, dihydromyricetin 및 myricetin등이 단리되었다.

• Elastomers and Composites
• /
• 제46권2호
• /
• pp.125-131
• /
• 2011

일정한 길이로 분쇄한 케냐프섬유를 일정한 비율로 PP수지에 복합화하여 섬유의 함량에 따른 기계적특성을 조사하였다. 케냐프 섬유의 함량이 증가할수록 인장강도, 굴곡탄성률, 충격강도, 비중, 열변형온도가 증가하는 경향을 나타내었으나 신장률, 굴곡강도, 용융유동지수는 감소하는 경향을 나타내었다. 기계적물성증가의 원인은 섬유와 PP간의 계면접촉면적의 증가와 섬유간의 연결간섭으로 고찰되었다. 케냐프섬유내에 존재하는 증발성추출물질이 PP와 의 계면접착에 있어서 감소에 영향을 미치는 것으로 고려된다.

• 한국펄프종이공학회:학술대회논문집
• /
• 한국펄프종이공학회 1999년도 Proceedings of Pre-symposium of the 10th ISWPC
• /
• pp.115-119
• /
• 1999

During mechanical pulp production and blcaching wood components, such as extractives, carbohydrates and lignin are dissolved and dispersed into the process waters. These components are called dissolved and colloidal substances(DCS). DCS can accumulate during water circulation and can in turn affect paper machine runnability and also the strength and optical properties of the paper. In this work DCS fraction origination from TMP process were treated with enzymes acting on triglycerides. glucomannans, and lignin and the effect of enzymatic treatments on the water composition as well as sheet properies were evaluated. Lipases were found to modify the chemical structure of the extractives resulting in more hydrophilic fibre surface and subsequent improvement in the sheet strength properties. Mannanase treatment, on the other hand, destabilized pitch. As a result, aggregation of pitch to the fibres was observed which in turn resulted in impaired strength properties. Laccase could effectively polymerize lignans and the reaction products seemed to be sorbed onto the fibres.