• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.5 s.113
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• pp.15-24
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• 2005

Different types of antioxidants compounds were prepared economically from natural sources. Application of these compounds towards photo stabilization of high yield bagasse pulp has been investigated. It was found that potato peel antioxidant followed by clove volatile oil provides lower brightness reversion and better photo stabilization effect for paper made from high yield bagasse pulp after exposure to UV lights in comparison with butyl hydroxy anisol or chamomile volatile oil.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.1-7
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• 2003

In this study, fiber mechanical pretreatment before refining was executed with the addition of papermaking addiditives to find synergistic effects on fiber property improvement. Three fiber furnishes (SwBKP, KOCC, and BCTMP), and five different additives (CMC, CPAM, PEO, NaOH, $Na_2O_2$) were used. It was confirmed again that fiber mechanical pretreatment using Hobart mixer was a special way to modify fiber properties, where fiber WRV (water retention value) increases without losing fiber length. For SwBKP, addition of small amount of CMC (0.2％ OD basis), and for KOCC, PEO (0.2％ OD basis) caused additional significant improvement of the fiber furnish properties, respectively. Other additives did not cause adverse effects on the mechanical pretreatment, or better. For BCTMP, NaOH addition followed by mechanical pretreatment caused more than 20％ improvement in tensile and tear strength simultaneously, compared to the control. The yellowing caused by the treatment of NaOH on BCTMP could be minimized by using $Na_2O_2$ without losing the positive effect of NaOH.

• Korean Journal of Microbiology
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• v.18 no.4
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• pp.172-179
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• 1980

The rhizome rot of ginger, caused by fusarium oxysporum f.zingiberi, gives a great deal of damages to the ginger farming in Korea. Main symptoms to the disease include the yellowing and blighting of the stems as the rotting of rhizomes. The infection rate was 20 percent in Bongdong, Jeonbug, whereas 10 percent in Susan, Chungnam. The rate was higher at the farm where gingers had been cultivated for many years. To control the disease, soil fungicides Dowfum MC-2 and Tolene C-17 were turned out to be more effective than Di-Trapex nad Daconil. Treatment of Benlate to the rhizome pieces, which were cut for propagation, also showed a better result as compared with that of Othocide. Dual treatment of both Dowfum MC-2 or Tolene C-17 to the farm soil and Benlate to the rhizome pieces was recommended for the best chemical control.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.975-977
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• 2010

Ammonium nitrogen is volatilized as ammonia at high pH soil. This study was conducted to observe an injury cause of egg plant grown in a high pH rockwool amended with ammonium phosphate. The etiolation symptom (yellowing) was appeared on veins of a leaf but not in healthy root when nutrient solution containing ammonium phosphate in addition to essential elements was applied in a top soil of which pH was 7.8. However, the same symptom did not appeared in the egg plant from the top soil in which the nutrition solution containing potassium phosphate instead of ammonium phosphate was applied. pHs were similar between these two different solutions. This revealed that the injury was caused by ammonia gas.

• Research in Plant Disease
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• v.29 no.2
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• pp.184-187
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• 2023

In May 2020, we surveyed disease occurrence on vegetables grown in Seosan area, Korea. During the disease survey, white rot symptoms were observed in Korean wild chive (Allium monanthum) plants growing in fields. The symptoms occurred mainly in the seed bulb-producing fields of the crop. The above ground parts of the diseased plants displayed premature yellowing and dying of older leaves and stunting of the plants. The bulbs and roots of the diseased plants turned black and rotted. The disease occurred in a range of 1-60% in four of the eight fields surveyed. Three isolates of Sclerotium sp. were obtained from the bulb lesions of diseased plants. All isolates were identified as Stromatinia cepivora based on the morphological characteristics and phylogenetic analysis. Pathogenicity of the isolates on Korean wild chive was confirmed by artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated fields. This is the first report of S. cepivora causing white rot in Korean wild chive.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.50-50
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• 2020

본 연구는 천궁에 감염된 오이모자이크바이러스(CMV)와 천궁엽맥황화바이러스(CnVYV)의 제거를 위해 항바이러스제인 리바비린 처리 효과를 조사하기 위해 수행되었다. 천궁 기내식물체의 생장점을 절취 후 항바이러스제 농도를 달리한 배지에서 생육을 유도한 후 RT-PCR 방법을 통해 바이러스 검출율을 조사하였다. 리바비린을 40 mg l^-1 농도로 처리하였을 때 바이러스 검출 종 수는 1.1종으로 감소하였다. 또한 동일조건에서 CMV와 CnVYV-2의 검출율은 무처리구 대비 각각 1/5과 1/2 수준으로 감소하였다. 하지만 리바비린 처리에 따른 CnVYV-1의 검출율은 감소하지 않았다. 리바바린 처리 농도에 따른 생존율은 처리구별로 유의적인 차이가 나타나지 않았으나, 40 mg l^-1 리바비린 처리구에서 신초 발생 수와 신초 길이는 무처리구 대비 절반 수준으로 감소하였다. 리바비린 처리를 통해 CMV와 CnVYV-2가 미검출된 23개체를 선발하였으며, 추가적인 바이러스 검정 단계를 거쳐 무병묘 생산에 활용될 것이다.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.210-218
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• 2015

Melon leaves showing yellowing symptoms were analyzed using electron microscopy and RT-PCR for major cucurbit-infecting-viruses (CMV, MNSV, CGMMV, SqMV, WMV, KGMMV, PRSV and ZYMV) reported in Korea, but these viruses were not detected. As the result of further analysis by next-generation sequencing (NGS), the virus was identified as Cucurbit aphid-borne yellows virus (CABYV), and then confirmed by RT-PCR using CABYV-specific primers. When photosynthetic capacity was measured based on chlorophyll fluorescence yield (ChlFY), the leaves of the diseased plants showed $4.09{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, which was one-third of the readings observed for unaffected normal plants ($12.36{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). The root functions of plants affected by leaf yellowing symptoms (LYS) was $0.28mg{\cdot}g^{-1}$, about half that measured for the normal unaffected plants ($0.48mg{\cdot}g^{-1}$). Cytological observations revealed that there were no morphological differences in the palisade parenchyma and mesophyll spongy cells of the leaves between the diseased and the normal plants. However, the same leaf cells of the affected plants contained more starch granules compared to those of the normal, unaffected plants. We conclude that the LYS of muskmelon is not merely a physiological disorder but a viral disease caused by CABYV and spread by aphids.

• Conservation Science in Museum
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• v.26
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• pp.25-34
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• 2021

3D printing technology has been actively applied for the restoration of cultural properties. However, its application to the restoration of glass cultural properties has not yet been reported and thus requires further study. In this study, 3D printing technology was used to restore a defective part of a glass sarira bottle that forms an element of a series of sarira reliquaries commissioned by Yi Seonggye (known as King Taejo after founding the Joseon Dynasty) that was excavated from Geumgangsan Mountain (designated as Treasure No. 1925) and is currently housed at the National Museum of Korea. The defective area was reproduced using 3D printing and the printed reproduction was reproduced again using an epoxy resin. This latter piece was used as the restoration component rather than the 3D printed element. After the completion of the conservation treatment, the materials used for the 3D printing were compared with transparent materials used to restore ceramics to evaluate their usability and stability. A total of five specimens were produced, including from photocurable resin made by a stereo lithography apparatus (SLA), epoxy resin, acrylic resin, and more. They were exposed to UV for 96 hours to test for yellowing. Of the two specimens made of photocurable resins and exposed to UV, one was sprayed with a UV blocking agent but the other was exposed as-is. The UV exposure test showed that the specimen made by the SLA and sprayed with a UV blocking agent and the specimen made of epoxy resin were stable in terms of yellowing with a change in the b-value was less than 1. They are thus considered to be suitable materials for the restoration of glass cultural properties. Such glass cultural properties are often diverse in shape and their restoration can be difficult as they generally consist of a range of complex parts that hamper restoration. In this regard, diverse materials should be considered when selecting materials for the restoration of glass cultural properties.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.495-500
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• 2001

Seed germination, seedling growth, plant establishment after transplanting, set of female flowers, and subsequent fruit growth were examined in cucumbers grown in soils having varying electrical conductivities (EC) of $1.0-5.0dS{\cdot}m^{-1}$ adjusted by adding different amount of a commercial compound fertilizer (N : $P_2O_5$ : $K_2O$ = 21 : 17 : 17). Slower seed germination was recorded in soils having EC value of $3.0dS{\cdot}m^{-1}$ or higher and little or no germination took place in soils with EC $4.0dS{\cdot}m^{-1}$ until 8 days after sowing. Suppression of seedling growth was apparent in soils having EC level of $2.5dS{\cdot}m^{-1}$. All seedlings died eventually at EC level of $3.5dS{\cdot}m^{-1}$. Leaf color became progressively dark green with the increase in EC from 1.0 to $3.0dS{\cdot}m^{-1}$. The first female flower was formed at higher node and the number of days required for the first flowering of female flower increased with the increase in EC values up to $3.0dS{\cdot}m^{-1}$. Occasionally, leaf yellowing and self-topping symptoms appeared in plants grown in soils having EC level of $3.0dS{\cdot}m^{-1}$.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.238-245
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• 2008

This study was carried out to investigate the effect of magnesium (Mg) concentrations in nutrient solution on growth of and nutrient uptake by 'Maehyang' strawberry. Tissue analysis based on dry weight and petiole sap were also conducted to determine the threshold level in plants when Mg deficiency disorders developed in strawberry plants. In the Mg deficient plants, the spotted yellowing or yellowing area developed on the interveinal area of mature leaves. The dark brown color also developed on the interveinal area of mature leaves with marginal browning or marginal necrosis. The response in dry weight production of 'Maehyang' strawberry to elevated Mg concentrations in nutrient solution was quadratic and the equation is y=6.84+1.7533x-$0.9278x^2$ $(R^2=0.1081^{***})$. But the Mg contents in tissue increased lineally with the equation of y=0.1764+0.1275x $(R^2=0.8307^{***})$. The trends of fresh weight production and Mg concentrations in petiole sap were also quadratic (y=24.127+7.3565x-$1.125x^2$, $R^2=0.2314^{^***}$) and linear (11.954+5.793x, $R^2=0.6869^{***}$), respectively. To prevent growth suppression, the Mg concentrations based on dry weight of above ground tissue and in petiole sap should be in the range of 0.30 to 0.65% and 19 to $40mg{\cdot}kg^{-1}$, respectively, fer the commercial production of 'Maehyang' strawberry.