• 펄프종이기술
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• 제45권4호
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• pp.16-20
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• 2013

Yellow poplar grown in Korea and imported eucalyptus were compared their kraft pulping characteristics and evaluated the replacing possibility of eucalyptus by yellow poplar. Difference between yellow poplar and eucalyptus were investigated in chemical composition and fiber morphology. Yellow poplar kraft pulp resulted in the higher yield, longer fiber length and thicker fiber, and higher pulp strength than that of eucalyptus. More xylan survived in eucalyptus than yellow poplar during kraft pulping, which led to similar pulp yield even though polysaccharides in Eucalyptus was 4.5% less than in yellow poplar. Longer and thicker yellow poplar pulp fiber resulted in better beating response and pulp strength properties.

• 펄프종이기술
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• 제42권3호
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• pp.22-27
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• 2010

Pulping properties of the imported mixed eucalyptus chips and the domestic yellow poplar chips were investigated for comparing two chips as the raw materials for the hardwood chemical pulp. Soda-AQ (anthraquinone) pulping was applied for this study. The pulp from yellow poplar showed higher pulp yield than pulp from mixed eucalyptus, which comes from the lower hot-water soluble extractives and the higher polysaccharides in yellow poplar chips than those of the mixed eucalyptus chips. The yellow poplar pulp had higher average fiber length and fiber width than those of the mixed eucalyptus pulp, which led to the better respond to beating and the higher tear strength than those of the pulp from the mixed eucalyptus chips.

• 한국가구학회지
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• 제24권4호
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• pp.345-349
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• 2013

Yellow poplar is well known commercial hardwood species in the world because of its availability, rapid growth, large size, excellent form, early natural pruning, and the good working quality of the wood. Therefore, yellow poplar (Liriodendron tulipifera L.) has been adopted in South Korea for decades ago, and its cultivating the saplings and silvicultural system have been studied. However, yellow poplar is still embroiled in controversy for utilization of use and worth. This species has not only advantages such as lower weight, light color, and higher machinability and bending processing, but also has disadvantages which are bad smell and different colors on heartwood and sapwood. In this study, the objective was that use of yellow poplar board as furniture materials by drying and painting process. Thirty years old yellow poplar was cut and dried for 7 days by high-frequency dryness. Adjustment of color tone to walnut color was conducted with multiple colorants and various number of spread times. Uniform color of yellow poplar on heartwood and sapwood was accomplished by applying 1 time stain (green), 2 times transparent primer, 1 time middle-painting (walnut), and 2 times top-painting (walnut) in sequentially. The painted yellow poplar board was used to manufacture table and dressing table. During the furniture manufacture process, no critical issues were occurred on part of jointing and painting. This painting method may be useful data for future use of yellow poplar as furniture materials.

• 한국산림과학회지
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• 제99권5호
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• pp.744-749
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• 2010

Enzymatic hydrolysate from non pre-treated biomass of yellow poplar (Liriodendron tulipifera) was prepared and used as resource for bioethanol production. Fresh branch (1 year old) of yellow poplar biomass was found to be a good resource for achieving high saccharification yields and bioethanol production. Chemical composition of yellow poplar varied significantly depending upon age of tree. Cellulose content in fresh branch and log (12 years old) of yellow poplar was 44.7 and 46.7% respectively. Enzymatic hydrolysis of raw biomass was carried out with commercial enzymes. Fresh branch of yellow poplar hydrolyzed more easily than log of yellow poplar tree. After 72 h of enzyme treatment the glucose concentration from Fresh branch of yellow poplar was 1.46 g/L and for the same treatment period log of yellow poplar produced 1.23 g/L of glucose. Saccharomyces cerevisiae KCTC 7296 fermented the enzyme hydrolysate to ethanol, however ethanol production was similar (~1.4 g/L) from both fresh branch and log yellow poplar hydrolysates after 96 h.

• 펄프종이기술
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• 제41권1호
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• pp.61-66
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• 2009

Effects of aqueous ammonia soaking treatments to yellow poplar (Liriodendron tulipifera L.) were investigated to focus on chemical compositional changes and enzymatic hydrolysis characteristics changes by this treatment. Treatment temperature and time were main variables. At 3 different levels of aqueous ammonia soaking temperature and time ($145^{\circ}C$ -1 h, $90^{\circ}C$ -16 h and $45^{\circ}C$ - 6 days), lower temperature and longer soaking time led to more xylan removal based on carbohydrate compositional analysis. However, at higher temperature treatment led to more enzymatic saccharification of cellulose to glucose by commercial cellulose mixtures (Celluclast 1.5L and Novozym 342 from Novozyme, Denmark). Cellulose hydrolysis was gradually increased with increasing enzymatic hydrolysis time but xylan hydrolysis was leveled out at early stage (less than 10 h) of enzymatic hydrolysis.

• 조경수
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• 통권129호
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• pp.14-19
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• 2012

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.520-520
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• 2009

Organic by-products derived from cellulose and lignin during organosolv pretreatments of yellow poplar wood (Liriodendron tulipifera) in the presence of $H_2SO_4$ and NaOH as catalysts, respectively, were subjected to various analyses to elucidate their effects on further performance of biological ethanol fermentation and provide preliminary data for the structure and utilization of organosolv lignin. Monomeric sugars amounted to ca. 2.2-7.7% in the organosoluble fraction of the organosolv pretreatment with $H_2SO_4$, while significantly low amount of sugars (0.2-0.3%) were determined in that of the organosolv pretreatment with NaOH. In case of addition of $H_2SO_4$ during organosolv pretreatment of biomass, a fermentation of the organosoluble fraction could be considered as an essential process to increase an efficiency of biomass utilization as well as yield of bioethanol. Precipitates, insoluble by-products in the solvent mixture, were also cficiency oed by diverse analytical methods and revealed that these were typically composed of a lignin moiety regardless of catalyst. According to the results of nuclear magnetic resonance (NMR), Fourier Tcinsform Infrared Spectroscopy (FT-IR) and Gel permeation chromatograp r (GPC), the main components of precipitates seem to be lignin polymers. However, their structures could be slightly modified during pretreatment and mixed with some carbohydrates by chemical bonds and/or physical associations.

• Journal of the Korean Wood Science and Technology
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• 제39권1호
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• pp.75-85
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• 2011

이 연구에서는 백합나무($Liriodendron$ $tulipifera$)를 옥살산으로 전처리한 시료로부터 에탄올 생산 가능성을 조사하고, response surface methodology (RSM)를 도입하여 전처리 조건을 분석하고자 한다. 산농도, 전처리 시간, 반응 온도를 조절하여 $2^3$ factorial central composite experimental design을 바탕으로 각기 다른 15가지의 전처리 조건에서 시험하였다(central point에서 2반복). 전처리 후 고체 시료는 발효 균주인 $Pichia$ $stipitis$를 사용하여 동시당화발효로 에탄올 생산에 이용되었으며, 각각의 시료에서의 72시간에서의 에탄올 생산량(y,g/${\ell}$)이 최대값으로, 종속변수로써 RSM에 적용되었다. $180^{\circ}C$에서 40분간 0.013 g/g의 옥살산으로 처리한 시료가 가장 많은 양의 에탄올(9.7 g/${\ell}$)을 생산하였으며, response surface methodology 분석에 따르면, 전처리 조건에서 온도 인자가 ethanol에 가장 큰 영향을 미치는 것으로 제시되었으며, 결과는 수식화되어 나타내었다.

• 한국가구학회지
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• 제11권1호
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• pp.69-74
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• 2000

Pinus $rigida{\times}taeda$ and Liriodendron tulipifira have been planted in this country for about 20 years. They are known as a relatively 13st-grown and useful species. The physical properties such as green moisture contents, specific gravities and dimensional shrinkages were examined with natively grown timbers. The kiln-dry schedules were developed with 30m thick boards by using an oven-fast-drying method. In both species the green MC's of sapwoods were higher than those of heartwoods, but their discrepancies were small. The green specific gravities of Pinus $rigida{\times}taeda$ and Liriodendron tulipifera were 0.48 and 0.41~O.42, respectively. The developed kiln-dry schedules were proven to minimize drying defects for the hoards of 30mm thickness and various width.

• Journal of the Korean Wood Science and Technology
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• 제42권4호
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• pp.357-366
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• 2014

백합나무 판재를 벽판재로 이용하기 위해 백합나무의 생재와 건조재에 대한 휘발성유기화합물(VOCs)과 알데히드류 방출 특성을 검토하였다. VOCs 및 formaldehyde를 포함한 aldehyde류의 방출량 측정은 다중이용시설 등의 실내공기질 관리법에 공시된 20 ${\ell}$ Chamber법에 따라 실시하였다. 백합나무의 생재 및 건조재에서는 30여 가지 이상의 VOCs가 검출되었다. 백합나무의 Total VOC 구성 비율 가운데 천연VOC (NVOC)의 비율은 11.1%로 다른 침엽수종과 비교하여 낮게 나타났다. 백합나무의 aldehyde류 분석 결과, 심재 및 변재에서 같은 3종(acetaldehyde, ketone, propionaldehyde)이 검출되었으며, formaldehyde의 방출량은 $4.01{\mu}g/m^3$ 이하로 나타났다. m-Tolualdehyde의 경우 백합나무 건조재의 심재에서만 $33.6{\mu}g/m^3$의 방출량을 보였으며, 심재와 변재 모두 ketone의 방출량이 가장 높게 나타났다. 백합나무 특유의 역한 냄새는 acetaldehyde와 propionaldehyde와 기타 VOCs에 의한 것으로 추정된다. 건조한 백합나무에서는 휘발성이 강한 ketone의 방출량이 증가하였다.