• Journal of Forest and Environmental Science
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• 제34권4호
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• pp.338-351
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• 2018

This study was conducted in a long-term experimental forest in the central hardwoods region of southwestern Michigan to retrospectively examine the role of past forest management practices and climate on red oak (Quercus rubra L.) productivity. Initially, in 1971, plots within the experimental forest were treated separately with a clearcut and shelterwood regeneration harvest in an attempt to increase red oak regeneration. From 1987-1989, a new study was initiated within a portion of the clearcut and shelterwood plots to evaluate the effectiveness of additional oak crop tree release using mechanical and chemical applications. Cumulative diameter and mortality rates of 719 red oaks were monitored across the four silvicultural treatments: Clearcut-A (clearcut without additional release treatment), Clearcut-B (clearcut with additional release treatment), Shelterwood-A (shelterwood without additional release), and Shelterwood-B (shelterwood with additional release) plus an untreated control. Increment cores were obtained from red oak trees and neighboring competitor species. Tree-ring analyses (dendrochronology) were applied to examine the effect of these silvicultural treatments and climatic factors (temperature and precipitation) on red oak productivity. The results indicated that crop tree release following a clearcut or shelterwood harvest reduced mortality rates and thus increased survival of red oak. Red oak in control plots or plots only receiving the initial regeneration harvesting treatment and no additional competition release were negatively affected by climatic stress, which included summer moisture stress. In contrast, red oak in plots that received the competition release treatment from shade tolerant tree species not only had higher tree level productivity (i.e., tree basal area) and lower mortality rates, but were also relatively more resilient to climatic stress by showing limited or no associations between climate and growth.

• 한국식품영양과학회지
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• 제46권10호
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• pp.1265-1269
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• 2017

본 연구에서는 신선 농산물의 미생물학적 안전성을 제고하기 위해 항균 효과가 있는 clove bud essential oil(CBEO)과 mild heat(MH) 처리를 병합 처리하여 Escherichia coli O157:H7이 접종된 red oak leaf의 미생물 수 변화를 측정하였다. 0.2% CBEO와 $50^{\circ}C$ MH 병합 처리구는 단순 물세척 처리구보다 1.45 log CFU/g 더 낮은 미생물 수를 나타내어 모든 병합 조건 중 가장 높은 미생물 제어 효과를 보였다. 또한, 본 병합 처리구는 비 세척 처리구와 비교하여 9일간의 저장 기간 동안 1.67~2.25 log CFU/g 더 낮은 미생물 수를 나타내어 미생물 제어 효과가 지속됨을 확인하였다. 따라서 이러한 결과들로부터 CBEO와 MH의 병합 세척 처리는 저장 중 red oak leaf와 같은 신선 농산물의 미생물학적 안전성을 확보하는 데 효과적으로 사용될 수 있다고 판단된다.

• 임산에너지
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• 제21권2호
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• pp.43-50
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• 2002

위스키 숙성용 목통으로서 한국산 참나무속 목재의 이용 가능성을 검토하기 위하여 도관직경, 방사조직 밀도, 방사조직 높이, 타일로시스의 존재 유ㆍ무 등 해부학적 특성과 알콜 침지 중의 밀도, 색농도 변화 및 흡수량을 조사하였다. 본 실험에 사용된 참나무속 목재는 모두 환공재였고, 단열방사조직과 광방사조직으로 구성된 복합방사조직을 가지고 있었으며, 방사유세포는 대부분이 평복세포였다. 타일로시스는 루부라참나무를 제외한 공시재 모두에서 존재하였다. 목재 밀도는 알콜 침적 후 많이 감소하였다. 알콜 색 농도는 떡갈나무와갈참나무가 다른 수종보다 더 짙은 황갈색을 나타냈다. 홉수량은 변재가 심재보다 높았고, 특히 red oak가 white oak보다 더 크게 나타났다. 결론적으로 국산 참나무속 수종은 위스키숙성용 목통으로 사용될 수 있을 것으로 판단되었다.

• Journal of the Korean Wood Science and Technology
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• 제42권6호
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• pp.691-699
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• 2014

용융점이 $138^{\circ}C$인 Bi-Sn 혼합합금 주입방법을 이용한 용융합금주입목재복합체의 제조를 통해 목재의 단점인 치수 안정성과 내구성의 개선을 하고자 3가지 주요 침 활엽수 수종의 수종별 최적주입조건을 구명하고, 주입에 따른 금속주입목재복합체의 중량증가율, 열전도도, 전기저항 등의 물리적 성질과 기계적 성질을 실험하여 다음과 같은 결과를 얻었다. 1. 금속주입목재의 최적처리 조건은 $185^{\circ}C$, 진공시간 10분 조건하에서 radiata pine의 경우 $10kgf/cm^2$ 가압시간 2분 30초, red oak는 $30kgf/cm^2$, 가압시간 10분, white oak는 $50kgf/cm^2$, 가압시간 10분에서 최적의 주입조건을 나타냈다. 2. 금속주입목재복합체의 외관적 특징은 전체적으로 재색은 회백색을 나타냈으며, 목재의 무늬를 그대로 유지하고 있다. 3. 침엽수 수종인 radiata pine은 저온용융합금주입처리로 인해 중량증가율은 12배, 밀도는 $6.13g/cm^3$으로 15배나 증가하였으나, 인테리어용으로 주로 사용되는 red oak와 white oak 등의 활엽수의 경우 목재해부학적 특성으로 의해 radiata pine보다는 낮은 5~6배의 밀도증가율을 나타냈다. 4. 주입된 목재는 침 활엽수 모두 금속주입으로 인해 수분흡수율과 두께팽윤율이 현저히 감소하였고, 매우 높은 치수 안정성을 나타냈으며, 금속주입목재복합체의 휨강도, 휨영계수, 경도 및 전기전도도와 열전도도 등도 무처리목재보다 매우 크게 향상되었다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.191.1-191
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• 1995

No Abstract, See Full Text

• Journal of the Korean Wood Science and Technology
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• 제24권4호
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• pp.87-92
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• 1996

When cutting 2.0cm-thick red oak and hard maple with an air-jet-assisted carbon-dioxide laser of 2kW output power, maximum feed speed at the point of full penetration of the beam decreased with increasing the angle between grain and cutting direction. Feed speed averaged 3.75 and 3.38 meters per minute for red oak and hard maple, respectively. Gray-level of laser-cut surfaces were analyzed by image analysis system. The highest gray level of laser-cut surface was obtained when red oak was cut parallel to grain by laser. Surface profiler was used to scan the sawn and laser-cut surfaces. Center line average roughnesses of laser-cut surfaces were higher than those of sawn surfaces. Scanning electron micrographs showed the cell walls which were melted by laser.

• Journal of Plant Biology
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• 제10권1_2호
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• pp.36-40
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• 1967

1. The effect of the pH value on P32 absorption of leaves of three forest trees under the water culture is investigated. 2. The degree of the P32 absorption to the pH value is quite different in each forest tree. 3. The phosphorus contents are proved higher in the leaves of Quercus accutissima(the saw shaped oak) than in the leaves of Pinus densiflora(the red pine) and Lespedeza bicolar (bush clover). 4. Larger contents of phosphorus are found in acidity plots than in alkalinity. The leaves of treated plot of the pH 4 (red pine), of the pH 5.0 (bush clover), and of the pH 5.0-6.5 (saw shaped oak) have a higher nutrient capital as indicated by P32 compared with that of the other pH values. 5. It is also noticed that P32 absorption capacity is decreased with the higher pH values. 6. The content of P of leaves shows the lowest value in the plot of the pH 6.5 (pine), of the pH 7.5(bush clover), and of the pH 9.0(saw shaped oak). It is also noticed that the red pine is to do very well in acid cultivation and then follow bush clover and saw shaped oak in the order.

• 한국식품저장유통학회지
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• 제18권6호
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• pp.891-897
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• 2011

일반적으로 적포도주는 장기간, 백포도주는 단기간 동안 발효가 끝난 뒤에 오크통에서 숙성 과정을 거치게 된다. 최근에는 오크통을 대신할 목적으로 포도주에 오크칩을 첨가하여 숙성하기도 한다. 본 연구에서는 다양한 시간별로 열처리한 국산 참나무편을 적포도주에 넣은 다음 숙성에 따른 변화를 비교해 봄으로써 색의 안정성과 풍미 개선에 도움을 줄 수 있는 적절한 전처리 조건을 알아보고자 하였다. 참나무편의 첨가 유무에 따른 알코올과 당도 및 총산 함량의 변화는 없었지만 pH의 경우는 참나무편 처리구에서 높게 나타났다. 총페놀 화합물의 함량은 참나무편 처리구에서 0.15-0.19%으로서 무처리구인 0.10%에 비하여 높은 값을 나타내었으나 레스베라트롤과 카테킨의 경우는 그 함량이 각각 3.88-5.05 ppm, 40.60-41.98 ppm으로 참나무 편의 첨가 또는 열처리 시간에 따른 유의적인 차이가 나타나지 않았다. 아세트알데히드의 함량은 참나무편 처리 유무에 영향이 없으나 메탄올, 에틸아세테이트 및 퓨젤유의 함량은 참나무편의 처리구에서 높게 나타났다. 참나무편의 열처리 시간이 길어질수록 intensity 값은 증가하였으며 또한 L, a, b 값의 감소량이 적은 것으로 보아 참나무편의 첨가가 포도주의 색 안정화에 기여함을 알 수 있었다. 관능 평가를 실시한 결과 색에서 참나무편을 첨가하지 않은 포도주가 가장 높은 점수를 받았으나 2시간 열처리한 참나무편을 처리한 포도주가 향과 맛, 전반적인 기호도에서 가장 높은 점수를 받았다.

• 한국초지조사료학회지
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• 제14권1호
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• pp.27-33
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• 1994

This study was conducted to determine the nutritional value of native oriental white oak(Quercus aliena Blume) browse by Korean native goats. Oak browse were mixed with grass hay(orchardgrass 60% and red clover 40%), varing in oak browse content. Diets included 30% oak browse and 70% grass hay, 60% oak browse and 40 % grass hay, and a 100% grass hay(contro1). Oak browse diets were higher in NDF, ADF, lignin, and tannin contents, but lower in CP content than the control diet with increased oak browse levels. Gross energy levels showed no difference between the control and oak browse diets. Dry matter intake was the lowest on diet containing oak browse 60%. Digestibility for DM, cellular constituents, NDF, and ADF showed lower for oak browse diets compared to control diet(P<0.05). Oak browse diets furnished significantly lower dietary N than &d the control diet. Fecal N losses generally increased with higher levels of oak browse levels(P<0.05). Apparently digested N and retained N were lower in oak browse diets than in control diet. The higher retained N was obtained in control diet than in oak browse diets. DE and ME declined linearly as oak browse levels increased when compared to control diet(P

• Journal of the Korean Wood Science and Technology
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• 제44권4호
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• pp.515-525
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• 2016

The Palsangjeon Pagoda is a five-story wooden building in the Beopjusa Temple area in the Songnisan national park in Chungcheongbuk-do, Korea. According to historical records, it was constructed in either AD 1605 or AD 1626. To specify the construction year more precisely, we took 41 wood samples for tree-ring analysis during repair actions in 2013; 28 from red pine (Pinus densiflora S. et Z.), 12 from oak (Quercus spp.), and 1 from fir (Abies spp.). The tree-ring boundaries became clearly visible by smoothing their cross-sectional surface and the tree-ring widths were measured under a stereo microscope. All tree-ring series were compared with each other to establish mean chronologies, which we then compared with local master chronologies established using tree rings collected from wooden elements of the Daeungjeon Hall which is the main building in the Beopjusa Temple area. As a result, it was verified that the red pines were felled in AD 1624 and in AD 1851. Moreover, it was verified that the oaks were also felled in AD 1624 based on cross-dating with the red pine chronology. We concluded that the Palsangjeon Wooden Pagoda was constructed in AD 1626, as mentioned in the historical record (Daeungdaekwangmyeongjeonbulsangki, 1630) and the letters on a purlin on the $4^{th}$ story, using oak and red pine felled in AD 1624 and repaired later on using red pine felled in AD 1851.