• 펄프종이기술
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• 제34권2호
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• pp.32-41
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• 2002

To prolong freshness and to reduce a decay rate of cut flowers during storage and distribution, a new packaging paper was developed with grapefruit seed extracts(GFSE) as a natural microorganism control agent. The GFSE was fractionated in order to identify antibiotic fractions by HPLC equipped with C18-reverse phase column chromatography. Among the active fractions, three ones were identified as 1-chloro-2-methyl-benzene (ο-toluene), N, N-dimethyl-benzenemethaneamine, and 1-〔2-(2-ethylethoxy)ethoxy〕-4-(1,1,3,3- tetra methyl)-benzene, while the other three remained unidentified. The GFSE-added paper displayed an effective inhibitory activity against putrefactive bacteria and fungi which were involved in the decay of flowers. Despite excellent antimicrobial acts of the GFSE-treated packaging paper, it was not possible to prevent the cut flowers from being dehydrated during storage, which led to the reduction of their fresh weight. However, additional treatment for giving water- repellency property to the GFSE-treated paper decreased a reduction rate of the fresh weight up to around 50% compared to the only GFSE-treated one.

• Journal of the Korean Wood Science and Technology
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• 제47권6호
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• pp.667-673
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• 2019

The performance of a wooden deck made of refractory materials that have difficulties in achieving target penetrations as stipulated in the specification and quality standards for treated wood in Korea, was assessed via a case study in this research. A wooden deck built in Jinju in 2009 was selected for this study because of its fabrication method using pressure and treated refractory materials. The penetration and retention analysis did not satisfy the domestic standard for treated wood. Inspection of the deck in 2019 revealed that the deck had been attacked by decay fungi. Cap rails showed much deeper and wider checking on their surface compared with the top and base rails, resulting in a severe fungal attack. The decking boards exhibited severe fungal decay primarily in the end parts. However, the rails and balusters without checks and posts were virtually free of fungal attack irrespective of the preservative penetration measures. Copper content in the soil 5 cm away from the deck was less than 150 mg/kg, implying that copper movement in the soil was very limited. These results suggest that the inhibition of surface propagation and the protection of end surfaces are essential factors in increasing the longevity of treated wooden decks; further, the results also showed that the deck was within an acceptable range from the point of copper contamination.

• 한국식품저장유통학회지
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• 제1권1호
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• pp.1-7
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• 1994

To investigate the effect of several bactericides and fungicides against fruit & vegetable decay grapefruit seed extract(GFSE) was tested in a dilution solution. GFSE was shown to be effective against decay and rind breakdown and to extend the shelf-life of fruits and vegetables during storage and tiansport. Antimicrobial efficiency of GFSE on a wide spectra of gram + & - bacteria, moulds and yeasts was demonstrated by the measurement of minimal inhibitory concentrations performed (Bacteria 10-500ppm, Fungi:250-1,000ppm, Yeasts:100-250ppm). GFSE was separated and extracted into water-soluble fraction, water-insoluble and non-dialyzed fraction to isolate the antimicrobial substances. The water-soluble fraction showed the most active antimicrobial effect. The antimicrobial substances were isolated by gas chromatography. As the result of the isolation using GC, Peak-D was found to be the antimicrobial compound in GFSE. The identification of the most antimicrobial substance was carried out by using GC-MS.

• Journal of the Korean Wood Science and Technology
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• 제34권1호
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• pp.61-67
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• 2006

본 연구는 목재부후균을 이용한 토양개량제를 개발하고자 리그닌 분해 우수균으로 선발된 SJ-28 균주의 처리가 상추재배에 미치는 효과를 조사하여 비교하였다. 시판 유기질퇴비에 균처리를 실시하여 상추를 재배하였다. Control 구에서의 총 중량이 약 2434 g인데 비해 균처리 토양개량제 처리구(FPG)에서는 총 중량이 약 4425 g으로 가장 높게 나타났다. 또한 FPG 처리구에서 토양에 유익한 방선균의 수가 많은 증가를 보였고 사상균의 수도 증가하였다. 반면 유익하지 않은 세균의 수도 FPG 처리구에서 가장 많은 감소를 나타내었다. 선발균 SJ-28 처리구에서 효과가 우수하게 나타나 토양개량제로서의 가능성을 보여 주었다.

• 한국작물학회지
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• 제53권3호
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• pp.303-307
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• 2008

Cotyledon Black Decay (CBD) on soybean sprout mimics the black spot due to microbial infection. CBD, not visible or predictable at seedlot state, for some reason, shows up exclusively on cotyledon of soybean sprout during sprouting process. Such an incidence rate fluctuated from 0.8 to 19.5% over three years from 2004. We suspected some pod-infecting anthracnose fungi and/or pod-blight pathogen, or pod-sucking bean bug, one of the major pests of soybean, might have involved, of which we ruled out fungal pathogen because it was preventable through heat treatment, a proven method for seedlot disinfestation. The healthy seeds artificially fed by bean bug for one to seven days were sprouted, and 6 to 41% of the soybean sprout revealed the CBD mimic to those occurred in soybean sprout from previous commercial seedlot screening experiments. This finding is the first report to confirm that bean bug damage to pod at $R_8$ stage is directly responsible for the CBD, which did not concur with any other deleterious effects on sprouting such as reduction in hypocotyls elongation and rooting except unsightly sprout quality. However, earlier feeding either at green pod or greenish yellow pod stage ($R_6$ -early $R_7$ stage) resulted in rather severe damages, which strikingly reduced hypocotyls growth to about one forth to about two third, as well as the reduction in rates of seed germination.

• Journal of the Korean Wood Science and Technology
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• 제45권1호
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• pp.12-19
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• 2017

황장목(黃腸木)은 적황색을 띠는 심재부의 비율이 높고 연륜폭이 매우 조밀하며 최소 수령이 100년 이상 되는 귀중한 소나무 자원이다. 조선시대에는 황장목을 궁궐, 사찰 등 중요 건축물에 사용하였다. 하지만 황장목의 재질특성에 관한 연구는 매우 부족한 실정이다. 본 연구에서는 황장목의 천연내구성을 검토하기 위하여 부후균 및 흰개미 저항성을 조사하였다. 공시균은 갈색부후균(Fomitopsis palustris)과 백색부후균(Trametes versicolor) 균주를 사용하였고, 공시 흰개미는 일본흰개미(Reticulitermes speratus)를 사용하였다. 그 결과, 갈색 및 백색부후균에 의한 중량감소율은 심재부에서 3.7~5.6%, 변재부에서는 16.1~26.3%로 나타났다. 또한, 흰개미 사충률은 심재부에서 약 47%로 매우 높게 나타났다. 이러한 결과를 통하여 황장목의 심재부는 부후균 및 흰개미에 대한 저항력이 뛰어난 것을 알 수 있었다.

• Journal of Forest and Environmental Science
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• 제36권3호
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• pp.225-232
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• 2020

Chemical modification of wood is an effective method to enhance the biological durability of wood with no toxic effect on the environment. In this study, wood of Triplochiton scleroxylon was modified using acetylation techniques. A total of one hundred wood blocks, (each 20×20×60 mm) obtained from a 22-year old T. scleroxylon tree were conditioned and acetylated at 120℃ in a bioreactor containing acetic anhydride for 60, 120, 180, 240 and 300 minutes. The percentage weight gain of acetylated wood was determined. The untreated (control) and treated blocks were exposed to Pleurotus ostreatus (white rot fungus) and Fibroporia vaillanti (brown rot fungus) after which moisture content (MC) and weight loss (WL) was monitored for 16 weeks. Data were analysed using descriptive and inferential statistics at p<0.05 level of significance. The percentage weight gain of acetylated wood samples increased with time from 10.4% (60 minutes) to 22.7% (300 minutes). MC of untreated blocks inoculated with Pleurotus ostreatus was significantly higher than those of Fibroporia vaillantii after 16 weeks exposure. There was no significant difference in the MC of the of the acetylated samples for the two fungi after 300 minutes reaction time. The WL of untreated blocks inoculated with Fibroporia vaillantii was higher than those of Pleurotus ostreatus, however, the two fungi showed no significant difference in the WL for the acetylated samples after 16 weeks exposure. Acetylation prevents moisture absorption and inhibition of fungi growth in acetylated wood compared to untreated wood, thereby enhancing the durability of Triplochiton scleroxylon.

• 한국균학회지
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• 제27권5호
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• pp.341-344
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• 1999

점버섯목의 점버섯속은 자낭각을 지닌 노란색이나 탁한 황토색의 자좌를 형성하며, 각진 입방형의 자낭포자를 지닌다. 열대지역인 말레이지아에서 발견된 Hypocrea microufa를 형태적으로 유사한 H. rufa, H. microsplendens와 비교하여 동정하였다. 본 H. microrufa는 열대지방에서는 최초로 발견 기록되며, 또한 전자현미경을 이용한 최초의 보고이다. 전자현미경을 이용한 자낭포자의 표면무늬도 검색표의 주된 분류 동정기준으로 사용하였다.

• 농업과학연구
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• 제37권3호
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• pp.465-469
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• 2010

In order to develop effective recycling technologies of disused railway wood ties, wood properties and residual creosote oil of wood ties were investigated. Among the total 50 wood ties, 32 wood ties were identified as tropical hardwood tree, such as, Keruing (Dipterocarpus spp.), Kempas (Koompassia malaccensis), Kapur (Dryobalanops spp.) Naytoh (Palaquium rostratum), and so on. Disused wood ties showed mostly sound structure without degradation of cell walls by decay fungi. Disused wood ties showed high strengths of bending and compressive parallel to grain because degradation of wood properties was hardly occurred in use under exterior condition. Disused railway wood ties had relatively poor depth of penetration and residual of creosote oil because of refractory wood structures. These results suggest that disused railway wood ties may be useful as recycling wood wastes.

• Journal of the Korean Wood Science and Technology
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• 제31권6호
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• pp.45-54
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• 2003

The density and strength of wood is affected by degradations and defects, such as voids and knots. Old wooden structures such as traditional cultural properties have been deteriorated by these types of defects. They were evaluated by a visual observation that is difficult to evaluate the inner deterioration in structures. In this study, three nondestructive testing techniques were investigated to detect the wooden structural members. Ultrasonic stress wave tests, drilling resistance tests and visual inspections were used to examine the structural wood members. Patterns of Resistograph using by drilling resistance tests could indicate the features of internal wood such as voids, knots, decay, fungi, and so on. The technique just like as ultrasonic stress wave tests, however, difficult to detect exactly area where small amounts of internal deterioration in logs are. In spite of results of ultrasonic stress wave test, the internal deterioration of wooden structural members could be evaluated by the relationship between ultrasonic stress wave tests and drilling resistance tests.