• 한국염색가공학회지
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• 제24권1호
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• pp.54-61
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• 2012

This study surveyed the preparation of 8oz coated fabric and the physical property of the coated fabric according to the treated condition for the sail yacht. And the coated fabrics were compared with the performance of overseas products for verification. Physical properties of the coated fabric treated with non-yellowing functional polyurethane resin were examined according to the treatment condition such as compression and ageing treatments. Finally, yellowing fastness to light for 60 hours was assessed. Considering the compression condition after coating, good physical property was obtained at $6kgf/cm^2$. Also, the performance of yellowing fastness was similar to performance of overseas goods.

• 한국토양비료학회지
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• 제42권6호
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• pp.409-414
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• 2009

아까시나무는 척박지에서 적응력이 뛰어나 과거 산림녹화와 사방조림 등에 많이 이용된 수종이다. 그러나 2000년 이후 황화현상이 국지적으로 빈번히 발생해 오다가 2006년에는 전국적으로 확산된 바 있다. 따라서 본 연구는 경기도 오산시 3개 지역에서 아까시나무의 황화현상 피해지와 미피해지 내에서 산림토양의 물리화학적 특성을 조사, 분석하여 그 관계성을 파악하고자 수행되었다. 조사지 일대 토양은 사방지토양, 갈색건조산림토양 및 갈색약건산림토양이 주를 이루었다. 피해지의 유효토심(16cm)과 전토심(25cm)은 미피해지(30cm, 56cm)에 비해 현저히 낮게 나타났다. 또한 미피해지에 비해 피해지 토양에서 고상률은 높은 반면 기상률은 낮고, 가비중도 높은 결과를 보여 근계부내 공기와 수분 이동성의 상대적 저하를 반영하였다. 또한 전체 조사지가 산성도가 매우 높은 강산성 토양이지만 피해지의 토양산도는 평균 pH 4.42로 미피해지의 pH 4.54보다 다소 낮았으며, 토양 내 유효인산, 칼슘, 마그네슘 함량과 염기포화율의 결과 역시 피해지에서 낮게 나타났다. 이러한 미피해지에 비해 열악한 황화현상 피해지의 토양 물리화학적 성질은 양분과 수분에 대한 보유 및 공급능력의 상대적 저하로 아까시나무 임분이 다른 환경 스트레스에 보다 민감하게 반응할 수 있음을 반영한다.

• Journal of Forest and Environmental Science
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• 제39권1호
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• pp.49-54
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• 2023

For unknown reasons, a few trees in a private chestnut orchard in Icheon si, Gyunggi-do suffered leaf chlorosis and growth decline. Based on symptoms, phytoplasma was a probable cause. Leaf samples were collected from two symptomatic and non-symptomatic trees in the orchard for phytoplasma detection. An amplicon of about 1.2 bp size was obtained from both symptomatic trees by PCR with the universal 16S rDNA primers. Sequences of these amplicons were found to have 99% nucleotide sequence identity to the corresponding genomic region of 16SrIII (X-disease group). More than 100 phytoplasma isolates, such as Candidatus phytoplasma pruni, Milkweed yellows phytoplasma, Goldenrod yellows phytoplasma, Tsuwabuki witches'-broom phytoplasma, Candidatus Phytoplasma trifolii, etc. were involved in the list. Phylogenetic analysis revealed that the sequence obtained in this study closely clustered with Candidatus phytoplasma groups. While one of the amplicons shared 91% identity with the Candidatus phytoplasma castaneae, the other shared only 47%. It needs further analysis and investigation to determine the exact taxonomy. Meanwhile, based on the analysis of the sequences, chlorosis, and small leaves were associated with phytoplasma.

• International Journal of Industrial Entomology and Biomaterials
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• 제44권1호
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• pp.12-20
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• 2022

In this research, the silk web was hot-pressed for various times, the effect of press time on the structure and mechanical properties of silk non-woven fabric was also investigated. The yellowing appeared in the silk non-woven fabric and became more apparent as press time was increased. The crystallinity of silk was decreased by the hot press treatment and it did not change significantly with an increase of hot press time. The porosity of silk non-woven fabric was constantly decreased until 120 s and it did not change much after that. The thickness of silk non-woven fabric was significantly decreased by a press time of 10 s and slightly decreased with a further increase of hot press time. The hot press treatment increased the maximum stress and elongation of silk non-woven fabrics. The press time had a significant impact on the mechanical properties of silk non-woven fabric, with 90 s being the optimum condition for the best work of rupture of silk non-woven fabric.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.669-675
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• 2009

연질 PVC 대체를 위한 비변색 타입의 무용제형 상온 액상수지를 폴리올을 경화제로 사용하는 폴리우레탄수지 구조제어 설계를 통한 프리폴리머 합성방법을 응용하여 제조할 수 있었다. Macro-glycol, 분자량 및 반응조건의 영향 등을 고찰하여 최적의 작업성과 물성을 가지는 무용제형 상온액상수지를 제조하였으며, 우수한 기계적인 특성과 함께 유색작업을 위한 안료의 분산성 등에서도 우수하였고, Tg가 $-40^{\circ}C$의 값을 나타내었다. 또한 자외선 노출이나 질소산화물에 의한 황변특성도 개선할 수 있었다.

• 한국연초학회지
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• 제6권2호
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• pp.147-153
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• 1984

During curing of aromatic tobacco leaves, coloring temperatures were set at 26, 30, 34, 38 and $42^{\circ}C$, and also leaf drying temperatures were established at 35, 40, 45, 50, 55 and $60^{\circ}C$, respectively, to investigate the thermal effect on characteristics of cured leaves. Appearance of yellow color from green was accelerated, the contents of non-volatile organic and higher fatty acids in leaves tended to increase with the higher yellowing temperature. Quality by price per kg was best at 45-$50^{\circ}C$ and score of smoking test was highest at 40-$50^{\circ}C$ during leaf drying stage. The concentrations of non-volatile organic acids and volatile essential oil inclined to decrease, but a reverse in this trend with higher fatty acids as temperature increased during leaf drying stage. The difference of other components was discussed.

• 공업화학
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• 제5권4호
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• pp.743-747
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• 1994

Acrylic urethane 수지의 경화반응에서 아크릴수지 중의 carboxylic acid 함유량과 dibutyltin dilaurate(DBTL)의 촉매 효과가 반응속도에 미치는 영향을 검토하였다. 얇은막의 상태에서 acrylic polyol과 지방족 isocyanate의 biuret화합물과의 경화반응은 2차식에 따른다. 그리고 acrylic polyol 중의 carboxylic acid의 양이 반응속도에 미치는 영향은 매우 크며, isocyanate지에 대한 강한 촉매 효과가 나타났다. 한편 carboxylic acid를 함유하지 않은 acrylic polyol에 DBTL을 첨가하면 촉매효과가 많이 나타나지만, carboxylic acid를 함유한 acrylic polyol의 경우에는 그 효과가 적게 나타났다.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.118-118
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• 2003

The occurrence of Fusarium wilt in strawberry fields in Korea was assessed from 2001 to 2003. Fusarium wilt was found from June to August in nursery beds, from September to October after planting in production beds, and from January to March during harvest. The symptoms seen were root rots, discolored vascular tissue in the crown and deformation and yellowing of central leaflets. The disease occurred in up to 30％ of plants in 37 of 214 fields surveyed. Fusarium of sporum Schlecht. ex Fr. f. sp. fragariae was frequently isolated from cvs. Dochiodome, Maehyang, Redpearl, Samaberry and Akihime. Factors affecting the occurrence of Fusarium wilt were investigated; infested soils had high salt concentrations, low pH, OM, average P2O5 and exchangeable. Fusarium wilt was more frequent following conventional basal fertilization than after non-nitrogen basal fertilization and more frequent following the use of NH4-N than after NO3-N.

• The Plant Pathology Journal
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• 제27권1호
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• pp.93-97
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• 2011

For quarantine purpose, we selected five plant RNA viruses including Cucumber vein yellowing virus (CVYV), Cucurbit yellow stunting disorder virus (CYSDV), Potato aucuba mosaic virus (PAMV), Potato yellow dwarf virus (PYDV), and Tomato chlorosis virus (ToCV), which are not reported in Korea and cause serious economic losses to the family Cucurbitaceae or Solanaceae. To detect those viruses, we employed RT-PCR technique with specific oligonucleotide primer pairs and tested their detection efficiency for each virus. To design RT-PCR primers, coat protein was used for CVYV, CYSDV, and ToCV whereas RNA polymerase and nucleocapsid regions were used for PAMV and PYDV, respectively. The development of an RT-PCR based method proved a useful tool for rapid detection and identification of quarantine virus infections.

• 공업화학
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• 제17권4호
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• pp.397-402
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• 2006

TFT-LCD TV용 백라이트 유니트(BLU)의 각 구성성분이 최종 광확산필름의 물리적, 전기적, 열적, 광학적 특성에 미치는 영향에 관하여 고찰하였다. 블로킹 방지층에 있어서는 $6{\mu}m$의 아크릴 비드를 0.5~1.5 wt%로 첨가했을 때 블로킹 방지성이 우수하였고, 4급 암모니움 염을 0.8 wt%로 첨가하였을 경우 Decay-Time 및 수분에 대한 안정성이 가장 우수한 결과를 나타내었다. 광확산층에 있어서는 아크릴 폴리올을 바인더 수지로서 사용하고, 무황변 타입의 HDI계 경화제를 바인더 수지에 대해 30~35 wt%로 첨가하였을 경우가 PET 필름 표면상에의 접착력, 경화속도 및 유연성 측면에서 가장 우수한 결과를 보였다. 또한 $20{\mu}m$의 다분산형 폴리스티렌($20{\mu}m$ PS) 및 폴리메틸메타크릴레이트($20{\mu}m$ PMMA) 비드를 바인더 수지 대비 250 wt%로 첨가하였을 경우에 가장 높은 법선휘도값을 얻을 수 있었으며, PS 입자를 사용했을 경우보다는 PMMA 입자를 사용했을 경우가 투과율 차이로 인해 더 높은 법선휘도값을 나타내었다.