• 보존과학회지
• /
• 제34권4호
• /
• pp.245-257
• /
• 2018

To investigate the deterioration of textiles with metal thread, I surveyed 40 textile objects, dating from the 11th to the 19th century from Korea, China, Japan, and Central Asia at the Metropolitan Museum of Art, New York. This survey included various types, widths, and thicknesses of metal thread. In addition, deterioration was examined under the microscope and color information was collected using the spectrophotometer. While investigating metal thread in the collections, I fabricated 12 different types of metal samples with metal leaf(24K gold, silver, and copper leaf), adhesive (hide animal glue and a mixture of hide animal glue and iron oxide red), and paper substrate(Korean mulberry and Taiwanese kozo paper). The accelerated deterioration process of those fabricated samples was carried out using a light box(UV and daylight), and a humidity cabinet. In the light experiment with blue scales textile fading card(aka, blue wool standard), the metal leaf began to peel off during the deterioration process with 756,000 lux-hours UV and daylight. In the temperature and humidity experiment, I could observe the reddish tarnish on copper, and some part of it began to peel off. Color reading on the light exposed samples showed that the degree of color change on the surface follows the amount of exposure as it increased over time. On the other hand, color change on the samples after artificial deterioration using temperature and humidity factors showed random change of color with occasional spikes. Distortion of original shape worsened in the samples exposed to temperature and humidity.

• 한국작물학회지
• /
• 제38권2호
• /
• pp.151-158
• /
• 1993

참당귀(Angelica gigas Nakai)의 재배에서 크게 문제가 되는 화성억제를 위해 온도, 일장 및 광도가 화아분화와 추대에 미치는 영향을 조사했으며, 관행재배와 화성을 추제시켜 재배생산된 근의 수량을 조사하여 연근별로 비교하였다. 본 시험에서 얻어진 결과를 요약하면 다음과 같다. 1. 자연온도처리(대조구)의 경우 11월 20일 처리구의 본엽 6～8매부터 화아분화 및 추대가 시작되어 처리기간이 길어질수록 추대율이 증가하다가 익년 1월 11일 이후부터는 변화가 없었으며 본엽 2～3매 는 어떤 구에서도 추대가 전혀 없었다. 2. 인공온도처리의 경우 처리온도가 높아질수록 주온감응한계엽령이 증가하였다. 즉, 1$^{\circ}C$, 5$^{\circ}C$, 9$^{\circ}C$ 처리구 각각 3매, 5매, 6매가지는 전혀 추대가 없었으며 8주 8매구에서도 1$^{\circ}C$에서 80%, 5$^{\circ}C$에서 45%, 9$^{\circ}C$에서 5%로 추대율이 저하하였다. 3. 참당귀의 추대율은 일장이 길어질수록 증가하였고, 광도시험에 있어서는 자연광구에서 가장 높았으나 광도가 감소할수록 점차 줄었으나 차광 50%까지 유의성이 인정되지 않았다. 4. 화도를 억제시켜 재배했을 때 10a당 건근중은 3년근이 가장 많았고 1ㆍ2년근에 비해 각각 3.6배, 2.4배 증수되었으며, 관행재배보다 2년근은 73.7%, 3년근은 159.6% 증수효과가 있었다.

• Journal of Forest and Environmental Science
• /
• 제38권2호
• /
• pp.110-121
• /
• 2022

Leaf functional traits widely have been used to understand the environmental controls of resource utilization strategy of plants along the environmental gradients. By using key leaf functional traits, we quantified the relationships between leaf traits and local climate throughout the distributional range of Rhododendron caucasicum Pall. in eastern and western Georgian mountains (the South Caucasus). Our results revealed, that all traits showed high levels of intraspecific variability across study locations and confirmed a strong phenotypic differentiation of leaf functional variation along the east-west longitudinal gradient in response to the local climate; out of the explored climatic variables, the moisture factors related to precipitation and number of precipitation and dry days for winter and growth seasons were more strongly related to leaf trait variation than the elevation and air temperature. Among studied leaf traits, the leaf specific area (SLA) showed the highest level of variability indicating the different resource utilization strategies of eastern and western-central Rh. caucasicum individuals. High SLA leaves for western-central Caucasian individuals work in relatively resource-rich environments (more humid in terms of precipitation amount and the number of precipitation days in winter) and could be explained by preferential allocation to photosynthesis and growth, while eastern Caucasian samples work in resource-poor environments (less humid in terms of precipitation amount and the number of precipitation days in winter) and the retention of captured resources is a higher priority appearing in a low SLA leaves. However, more evidence from a broader study of the species throughout its distribution range by including additional environmental factors and molecular markers are needed for firmer conclusions of intraspecific variability of Rh. caucasicum.

• Journal of Ecology and Environment
• /
• 제48권2호
• /
• pp.152-162
• /
• 2024

Background: Plant species of the alpine treeline ecotone are highly sensitive to climate change and may adjust their population dynamics, and functional traits in response to changing climate. This study examined regeneration patterns and leaf traits variations in an important treeline ecotone element Rhododendron campanulatum along the elevation gradient in western Nepal to assess its potential adaptive responses to climate change. The distribution range of R. campanulatum (3,400-3,800 m above sea level [a.s.l.]) was divided into five horizontal bands, each with a 100 m elevational range. Eight plots (10 m × 10 m) were sampled in each band, resulting into a total of 40 plots. In each plot, all R. campanulatum individuals and co-occurring tree species were counted. From each elevation, R. campanulatum leaf samples were collected to determine leaf dimensions, leaf density, specific leaf area (SLA), and stomatal density (SD). Results: The density-diameter curve indicated that R. campanulatum was regenerating well, with enhanced regeneration at higher elevation (3,800 m a.s.l.) than at lower. Tree canopy cover appeared to be the major determinant of R. campanulatum regeneration, as indicated by a higher number of seedlings in treeless stands. With increasing elevation, the leaf length, width, SLA, and stomata length decreased but leaf thickness and SD increased. Conclusions: Overall, a higher regeneration and lower SLA with the high SD in the leaves at the upper limit of the species distribution suggested that R. campanulatum is well adapted at its upper distribution range with the possibility of upslope range shift as temperature increases.

• 한국유기농업학회지
• /
• 제15권1호
• /
• pp.71-84
• /
• 2007

[ $CO_2$ ] 농도증대와 고온조건이 피망의 생육 및 수량에 미치는 영향을 분석하여 향후 지구 온난화에 따른 작물분야에서의 대응방안 마련을 위한 기초자료를 얻고자 시험한 결과를 하면 다음과 같다. 파종 후 개화소요일은 $CO_2$ 농도처리 간에는 400ppm 처리구에서 56.3일, $CO_2$ 농도를 배증시킨 800 ppm에서는 55.7일로 대차 없었으나, 온도 처리간에는 $35/25^{\circ}C$의 고온구가 52.5일로 가장 짧게 소요되었다. 출현 후 15주의 피망의 생육 및 수량을 보면 초장은 $CO_2$ 농도간에는 유의성이 없었으며, 온도간에는 유의성이 인정되어 $30/20^{\circ}C$ 처리구에서 초장이 54.5cm로 가장 컷다. 생육기간중 경시적인 초장신장은 $CO_2$ 농도가 높은 구에서 초장신장이 억제되었으며, 온도가 높을수록 초장신장이 커졌다. 주당 엽면적은 400ppm 처리구가 평균 $6,008.8cm^2$, 800ppm 처리구가 $5,225.1cm^2$로 400ppm 처리구가 약 15% 엽면적이 높았다. 엽건물중은 $CO_2$ 농도간 및 온도처리간에 유의성을 나타내었다. 800ppm 처리구의 평균 엽건물중은 44.1g으로 400ppm 처리구의 37.2g에 비해 18.5% 높았으며, 온도처리간에는 고온구인 $35/25^{\circ}C$구가 49.8g으로 가장 높았다. 총 지상부 건물중도 $CO_2$ 농도간 및 온도처리간에 유의성을 나타내었으며, 800ppm 처리구가 141.4g으로 400ppm 처리구의 119.9g보다 17.9%나 높았다. 온도처리별 지상부 건물중은 $30/20^{\circ}C$ 처리구가 168.9g으로 가장 높았으며, 고온구인 $35/25^{\circ}C$구가 102.3g으로 가장 낮았다. 과실의 건물중(수량)은 800ppm 처리구가 59.5g으로, 400ppm 처리구의 44.3g에 비해 약 34.3% 많아 피망의 경우 $CO_2$, 농도 증대가 수량증대에 유리할 것으로 판단되었으며, $CO_2$, 농도가 높을 때(800ppm)에는 저온($25/15^{\circ}C$)에서, 평상적인 $CO_2$, 농도에서는 고온($30/20^{\circ}C$) 조건에서 수량이 높아지는 경향이었다. $CO_2$, 농도에 따른 비엽면적은 800ppm의 117.4보다는 400ppm의 159.1에서 35.5% 커, $CO_2$, 농도가 증대하면 잎의 두께가 두꺼워짐을 알 수 있었다. 또한 작물학적 특성들간 상관관계를 보면 엽면적은 주당 착과수 및 과실 건물중과 유의한 부의 상관관계를 나타내어 엽면적이 클수록 수량은 낮아졌다. 주당 과실 건물중과 주당 착과수, 지상부 총건물중과는 유의한 정의 상관관계를 보여 착과수가 많을수록 지상부 건물중이 클수록 수량이 증대함을 알 수 있었다.

• The Plant Pathology Journal
• /
• 제17권5호
• /
• pp.249-256
• /
• 2001

Xanthomonas axonopodis pv. glycines 8ra produces a bacteriocin called glycinecinA, which specifically inhibits the growth of bacteria belonging to Xanthomonas species. GlycinecinA was produced by culturing Escherichia coli DH5 containing biosynthetic genes for glycinecinA, and was tested for its control effect against X. vesicatoria on red pepper and X. oryzae pv. oryzae on rice. The bacteriocin activity was much higher in the cell extract than in the supernatant. It reached a maximum level at the stationary phase, ws maintained up to 2 months at room temperature and approximately 10 months at $4^{\circ}$. The optimum concentration of glycinecinA for the control in the greenhouse and in the field was 12,800 AU/ml. In this study, the activity of glycinecinA on rice and red pepper leaves continued for 7-8 days, during which the pathogen populations remained at low levels. Bacterial leaf spot of red pepper and bacterial leaf blight of rice were significantly reduced by the bacteriocin treatments. The control efficacy was as high as, or even higher than, the chemical treatment of copper hydroxide. These results suggest that the bacteriocin is a potential control agent for bacterial diseases.

• 한국연초학회지
• /
• 제32권2호
• /
• pp.88-94
• /
• 2010

The ether extract(EE) of leaf tobacco contains diverse compounds such as lipid, resinoid, paraffin hydrocarbons and pigments. Although the correlation of EE concentertion with leaf tobacco has not been established clearly, it is known that in some concentration range, EE concentration of leaf tobacco exerts good influence on the quality of tobacco. Recently, The American Oil Chemist's Society introduced new method(Am 5-04; AOCS, 2009) to determine EE concentration by AT15 extractor. This method is based on extraction with organic solvent at relatively high temperature and pressure, which significantly reduces the extraction time and ensures safety. The aim of this study is to optimize analytical condition of AOCS method for analyzing EE concentration of leaf tobacco. When sample pre-drying time and extraction time of XT15 were set to 3 hour and 30 minute and 30 minute respectively, EE concentration obtained from AOAC method. Statistical analysis(T-test) showed that there is no difference(P>0.05) between EE concentrations from two methods.

• Mycobiology
• /
• 제31권1호
• /
• pp.57-59
• /
• 2003

A leaf spot of cotton rose(Hibiscus mutabilis) occurred severely in the flower beds of cotton rose around Uiryeong-gun, Gyeongnam Province in Korea. The causal fungus was identified as Corynespora cassiicola on the basis of cultural and morphological characteristics of the fungus. The fungus grew well on potato dextrose agar and the colony color was gray to brown. Conidia were solitary or catenate, obclavate to cylindrical in shape, and pale olivaceous brown or brown in color. They had 420 pseudosepta, and measured $35.2{\sim}173.6{\times}8.8{\sim}19.9{\mu}m$. Conidia germinated as a bipolar type. Conidiophores were pale to mid brown in color, and measured $74.2{\sim}275.6{\times}3.8{\sim}10.8{\mu}m$. Optimal temperature for mycelial growth was $30^{\circ}C$. The fungal isolate grown on PDA showed strong pathogenicity to cotton rose plant. This is the first report on the corynespora leaf spot of cotton rose(Hibiscus mutabilis) caused by Corynespora cassiicola in Korea.

• Journal of Ginseng Research
• /
• 제8권2호
• /
• pp.172-177
• /
• 1984

Saponins in leaf and stem of Gynostemma pentaphyllum that was collected from Jeju Island were extracted by the method for ginseng saponin. Comparison by overlapping chromatogram(HPLC) of pentaphyllum on that of ginseng and cochromatogram and ginseng although ginsenoside Rg2, Rg1 and Rf might be in common with rare possibility. It seems to be little difference in the kind of saponin glycosides between leaf and stem of pentaphyllum. Saponin content in leaf of pentaphyllum was higher than in stem, and much higher than those in ginseng. The kind of saponin glycoside in pentaphyllum appeared to be less than 22 and greater than those in ginseng. There was almost no change in saponins of pentaphyllum in methanol for 3 years at room temperature.

• 한국산림과학회지
• /
• 제103권4호
• /
• pp.547-555
• /
• 2014

본 연구는 병풍쌈을 대상으로 종자의 전처리(상온건조, 저온건조, 수침처리를 각각 48시간 동안 실시)에 따른 차광처리별 발아특성과 유묘의 생장특성을 알아보고자 하였다. 실험은 전처리된 종자를 용기에 파종하여 차광시설(전광 및 35%, 50%, 75%, 95% 차광)에 각각 배치하여 진행하였다. 종자의 발아율은 25.7~61.1%의 범위로 조사되었으며 전광 내 수침처리구에서 61.1%로 가장 높게 나타났다. 병풍쌈 유묘의 초장생장은 95% 차광에서, 근원직경은 전광에서 가장 높은 것으로 조사되었다. 엽생장(엽면적, 엽장, 엽폭, 엽두께)과 뿌리생장(전체뿌리길이, 뿌리투영단면적, 뿌리표면적, 평균뿌리직경, 뿌리부피)은 전반적으로 35%~75% 차광에서 양호한 것으로 조사되었으며 95% 차광에서는 가장 저조한 생장을 보였다. 또한, 부위별(잎, 줄기, 뿌리) 및 전체 생중랑은 모두 50% 차광에서, 지상부(잎, 줄기)와 전체 건중량은 75% 차광에서 가장 높은 것으로 조사되었으며 95% 차광에서는 모든 부위에서 가장 저조한 생장을 보인 것으로 나타났다 따라서 본 실험의 결과를 종합하면, 병풍쌈의 종자는 수침처리하여 높은 광도에서 발아시킨 후 어느 정도의 차광처리(50%~75% 차광)를 하는 것이 용기 유묘생산에 보다 효과적일 것으로 판단된다.