• 임산에너지
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• 제22권3호
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• pp.43-48
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• 2003

변색, 열화 등의 문제점을 보완하기 위해 볏짚 추출물을 이용하여 미표백 한지의 천연색에 가장 근접할 수 있는 염색법을 개발코자 본 실험을 수행하였다. 한지의 염색성은 염료 추출시간 및 염색시간보다 추출방법의 영향을 가장 크게 받는 것으로 나타났으며, 열수추출물이 냉수추출보다 우수하였다. 열수추출은 추출시간 및 염색시간에 관계없이 대조구와 유사한 색상을 나타냈으며 120분 추출, 45분간 염색한 한지는 대조구와 거의 동일한 색상을 나타냈다. 볏짚의 열수추출물은 천연염료로서 다양한 미표백 자연색의 발현이 가능한 우수한 염색특성을 나타냈다.

• 펄프종이기술
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• 제43권1호
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• pp.83-91
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• 2011

Hemicelluloses are useful materials for papermaking and other biotechnological applications. To recover and further utilize the hemicelluloses, this study carried out the pre-extraction of the hemicelluloses from Korean mixed hardwoods chips using hot water and sodium hydroxide solution at various temperature and time conditions. Through the hot water pre-extraction, the wood components of 22% was extracted and the 35% of the hemicelluloses which were contained in the original wood chips were dissolved into the pre-extractives. The yield of the pre-extractives was more significantly influenced by the pre-extraction temperature than the time. The pre-extractives with the yield of 30% could be obtained by alkali pre-extraction and alkali concentration was the most important factor. It had lower hemicellulose content but high molecular weight, compared with the hot water pre-extractives.

• Journal of the Korean Wood Science and Technology
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• 제24권4호
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• pp.1-6
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• 1996

Extracts from bark have been studied with a view to producing water-proof wood adhesives. Lately many softwoods, such as radiata pine from New Zealand and larch from Siberia, Russia, have been imported and utilized, and their residual barks would be expecting as potential raw materials for something useful chemicals. The great effort toward utilization of bark extractives as a chemical feedstock has been made on a worldwide level. However few report has been done for the utilization of tree bark extractives in Korea. Hot-water extracts were prepared from barks of Japanese larch(Larix leptolepis). Siberian larch(Larix gmelinii) and Radiata pine(Pinus radiata). The effect of various factors, such as particle size, liquor ratio, extraction temperature, and reaction time, on the extractive yields was discussed. Particle sizes affected the hot-water extractives: the finer the particle size, the higher extractives and extract efficiency. Higher temperature and higher liquor ratio were more effective. Extractives from Japanese larch were relatively less than those from Siberian larch and Radiata pine barks. Formaldehyde precipitates was the highest in extractives of Radiata pine barks. It could be concluded that Siberian larch bark was the best raw material for tannin adhesives, because its extractive yield was higher than those of the other barks.

• Journal of the Korean Wood Science and Technology
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• 제21권2호
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• pp.67-72
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• 1993

Hot water extractives of sawdust/particle from domestic and foreign wood species, which were composed of pitch pine, Korean pine, larch, Italy poplar, acacia and oak as Korean wood species, Malaysian oil palm and German spruce were quantitatively analyzed with thin layer chromatography. Sugar components of saccharose, galactose, glucose, fructose and arabinose were contained in these wood species. It was assumed that arabinose and glucose are major inhibitory components against cement hardening in larch and oil palm, respectively, since both species contain a large amount of each sugar. In contrast, fructose might not influence so badly on a cement hardening, when considering that fructose was contained much in Italy poplar with a good cement hardening character. Galactose was a minor component.

• 펄프종이기술
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• 제48권3호
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• pp.57-65
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• 2016

Indigo (Polygonum tinctorium L.) is a typical blue dye which had been used from ancient times. This study was going to shade the complicated traditional methods extracting indigo dye by the fermentation and producing as adsorbate on calcium hydroxide, which says so called as the 'Indigo lime'. Accordingly we were going to make indigo through the hydrolysis of the hot water extractives of indigo leaves simply. During hot-water extraction, ${\beta}$-glucosidase which required hydrolysis of the linkage between indigo and glucose was not activated. To achieve this goal, indican was acid-hydrolyzed to glucose and indigo. The acetic acid, citric acid, hydrochloric acid, and sulfuric acid were used for the hydrolysis of hot water extractives. The hydrolysis conditions of extractives performed in water bath at $80^{\circ}C$ for 120 minutes and in an autoclave for 120 minutes. In the acid hydrolysis of extracted indican by hot water, the indican yields of acetic acid and hydrochloric acid hydrolysis were higher than sulfuric acid in water bath. Also, the indican yield of hydrochloric acid hydrolysis was better than sulfuric acid in autoclave. The hot water extracted indican was confirmed by HPLC analysis and its structure was confirmed by UV-Vis and FT-IR spectroscopy, compared with isolated indigo and commercial synthesized indigo. This improved extraction and hydrolysis methods can be replace the traditional indigo making method.

• Journal of the Korean Wood Science and Technology
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• 제30권3호
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• pp.109-115
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• 2002

Mycelial growth of L. edodes by pretreatments of softwood was studied on a sawdust medium. The sawdust used was from the following softwood species : Larix leptolepis, Pinus densiflora and Pinus koraiensis. The pretreatment consisted of cold-water (48 h), hot-water (3 h) and steam extractions (3 h) at a ratio of 500 g : 3,000 mL (sawdust : distilled water). The sawdust medium was a mixture of 76% sawdust, 20% rice bran, 3% glucose, 0.4% potassium nitrate and 0.6% calcium carbonate. Following sawdust pretreatments proved most suitable : L. leptolepis (steam extraction), P. densiflora (hot-water extraction) and P. koraiensis (hot-water extraction). Mycelial growth on P. koraiensis sawdust increased in proportion to an increase in hot-water extraction time. Mycelial growth was optimum on the sawdust extracted for 12 hours, hot-water extraction beyond this period proved unsuitable. With the exception of P. densiflora at 100 ㎍/mL, antifungal activity occurred in every sample. Maximum inhibition of mycelial growth was obtained from following concentration of hot-water extractives : P. densiflora (10⁴ ㎍/mL) and P. koraiensis (10⁴ ㎍/mL). This study has provided useful preliminary information for the cultivation of L. edodes.

• Journal of the Korean Wood Science and Technology
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• 제24권3호
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• pp.51-56
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• 1996

The Bark lignin(alkali- and acid lignin), bark extractives(hot water-and $Na_2SO_3$ extractives) of Quercus acutissima and Pinus densiflora, and flavonoids were used to detect heavy metal adsorption. The adsorption ratio of heavy metals by lignin was assigned for 40 to 50%, but was not dependent on lignin kinds. However, in case of the addition of light metals such as $Ca^{++}$ and $Mg^{++}$ to lignin the adsorption ratio was increased by 20 to 40%, and $Pb^{++}$ was almost completely adsorbed. On hot water extractives, the adsorption ratio was very low because the substrate was water-soluble, so the substrate should be water-insoluble to adsorb the heavy metals. However, the adsorption ratios of $Cd^{++}$ and $Pb^{++}$ on $Na_2SO_3$ extractives were significantly increased, while those of $Zn^{++}$ and $Cu^{++}$, were similar to lignin. When four kinds of heavy metals were treated to $Na_2SO_3$ extractives together, more than 97% of $Pb^{++}$ and $Cu^{++}$ was adsorbed_ and $Zn^{++}$ was more adsorbed by 40%, and $Cd^{++}$ was not changed, comparing with the case that on kind of heavy metal was treated. There were differences between adsorption ratio of the kinds of flavonoids and heavy metals, and the adsorption ratio of heavy metals was assigned to 20 to 45% per 0.1g flavonoid.

• Journal of the Korean Wood Science and Technology
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• 제20권2호
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• pp.73-80
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• 1992

The effect of presteaming on native oak specimens(Quercus serrata) of 2.5cm thick were investigated by measuring specific gravities, internal moisture gradients, residual extractives, and transport rates of free and bound water. The specific gravities and internal moisture gradients of the presteamed samples did not much deviate from those of the controls, but after presteaming discrepancy in moisture content between specimens lessened. The amount of residual hot-water extractives of the presteamed samples were less than those of the controls by 25%. The transport rates of bound water were determined by measuring steady-state diffusion coefficients with a vapormeter cup. After presteaming the diffusion coefficients in radial direction increased by 35%, but decreased those in the tangential direction.

• 한국산림과학회지
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• 제58권1호
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• pp.23-26
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• 1982

지리산산(智異山産) 굴참나무재(材)와 졸참나무재(材)에 대하여 그 화학적(化學的) 조성분(組成分)을 심재(心材), 변재별(邊材別)로 분석(分析) 조사(調査)하여 본 바 그 결과(結果)를 요약(要約)하연 다음과 같다. 굴참나무재(材)에 있어서는 변재회분함량(邊材灰分含量) 0.57%, 심재(心材) 1.00%였고 냉수추출물(冷水抽出物)은 변재(邊材) 5.74%, 심재(心材) 4.77%였으며 열수추출물(熱水抽出物)에 있어서는 변재(邊材) 6.33%, 심재(心材) 6.33%였고 하성(荷性)soda 추출물(抽出物)은 변재(邊材) 15.52%, 심재(心材) 15.63%였다. Alcohol-benzol 추출물(抽出物)은 변재부(邊材部) 4.89%, 심재부(心材部) 2.96%였고 Holocellulose 함량(含量)에 있어서는 변재(邊材) 73.19%, 심재(心材) 78.83%였고 Lignin은 변재(邊材) 21.76%, 심재(心材) 18.14%였고 Pentosan 함량(含量)은 변재(邊材) 15.92%, 심재(心材) 26.50%였다. 졸참나무재(材) 분석결과(分析結果)를 보면 회분함량(灰分含量)은 변재(邊材), 심재(心材) 각각(各各) 0.26%, 0.27%이고 냉수(冷水) 추출물(抽出物)은 변재(邊材) 2.81%, 심재(心材) 2.04%였으며 열수(熱水) 추출물(抽出物)은 변재(邊材) 5.32%, 심재(心材) 7.08%였고 하성(荷性)soda 추출물(抽出物)은 변재(邊材) 15.73%, 심재(心材) 16.55%였으며 Alcohol-benzol 추출물(抽出物)은 변재(邊材) 3.93%, 심재(心材) 3.51%로 나타났다. Holocellulose 함량(含量)은 변재(邊材), 심재(心材) 각각(各各) 74.21%, 74.84%였고 Lignin은 변재(邊材) 14.11%, 심재(心材) 19.19%였으며 Pentosan은 변재(邊材) 20.7.5%, 심재(心材) 21.44%의 함량치(含量値)를 보였다. 전체적(全體的)으로 보면 굴참나무재(材)는 변재(邊材), 심재간(心材間)에 회분(灰分), Holocellulose, Lignin, Pentosan함량(含量)에서 특징적(特徵的)인 차이(差異)를 보였으나 졸참나무재(材)는 Lignin함량(含量)에서 다소간(多少間)의 차이(差異)가 인정(認定)될 뿐 그 이외(以外)에 변심재간(邊心材間)에 특수(特殊)한 차이(差異)를 인정(認定)할 수 없었다.

• 펄프종이기술
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• 제43권5호
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• pp.60-67
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• 2011

Hemicelluloses pre-extracted from Korean mixed wood chip were investigated as a wet-end additive. Hemicelluloses dissolved in hot water and alkali solution were isolated by ethyl alcohol precipitation from pre-extractives. They showed molecular weight of 9,000 ~ 27,000 g/mol as revealed by size exclusion chromatography. The reduction of molecular weight through hot water extraction was caused by autohydrolysis. Chemical composition of the hemicelluloses were analyzed with high-performance liquid chromatography and UV-Vis spectroscopy. As the surface charge of isolated hemicelluloses were negative, the adsorption of hemicelluloses onto softwood unbleached kraft pulp fiber was promoted by poly-DADMAC. The physical properties of handsheets increased as the molecular weight of hemicellulose increased. On the other hands, the optical property decreased with hemicellulose adsorption.