• Proceedings of the KSRS Conference
• /
• 2005.10a
• /
• pp.7-10
• /
• 2005

Plant water deficiency during drought season causes physiological stress and can be a critical indicator of forest fire vulnerability. In this study, we attempt to analyze the spectral characteristics of water stressed vegetation by using the laboratory measurement on leaf samples and the canopy reflectance spectra extracted from satellite hyperspectral image data. Leaf-level reflectance spectra were measured by varying moisture content using a portable spectro-radiometer. Canopy reflectance spectra of sample forest stands of two primary species (pine and oak) located in central part of the Korean peninsula were extracted from EO-l Hyperion imaging spectrometer data obtained during the drought season in 2001 and the normal precipitation year in 2002. The preliminary analysis on the reflectance spectra shows that the spectral characteristics of leaf samples are not compatible with the ones obtained from canopy level. Although moisture content of vegetation can be influential to the radiant flux reflected from leaf-level, it may not be very straightforward to obtain the spectral characteristics that are directly related to the level of canopy moisture content. Canopy spectra form forest stands can be varied by structural variables (such as LAt, percent coverage, and biomass) other than canopy moisture content.

• Bulletin of the Korean Chemical Society
• /
• v.35 no.3
• /
• pp.919-924
• /
• 2014

Ambient ionization can be achieved by generating an electrospray directly from plant tissue ("leaf spray"). The resulting mass spectra are characteristic of ionizable phytochemicals in the plant material. By subtracting the leaf spray spectra recorded from the petals of two hibiscus species H. moscheutos and H. syriacus one gains rapid access to the metabolites that differ most in the two petals. One such compound was identified as the sambubioside of quercitin (or delphinidin) while others are known flavones. Major interest centered on a $C_{19}H_{29}NO_5$ compound that occurs only in the large H. moscheutos bloom. Attempts were made to characterize this compound by mass spectrometry alone as a test of such an approach. This showed that the compound is an alkaloid, assigned to the polyhydroxylated pyrrolidine class, and bound via a $C_3$ hydrocarbon unit to a monoterpene.

• Journal of the Korean Society of Tobacco Science
• /
• v.21 no.1
• /
• pp.95-101
• /
• 1999

This study was carried out to analyze chemical components in burley tobacco using near infrared spectroscopy(NIRS). Samples were collected in '96 and '97 crop year. Calibration equations were developed by modified partial least square. The standard error performance(SEP) of '96 crop year samples between NIRS and standard laboratory analysis were 0.25% for nicotine, 0.18% for total nitrogen, 0.59% for crude ash, 0.32% for ether extracts, and 0.14% for chlorine, respectively. The analytical results of '97 crop year samples were similar to those of '96 crop year samples. The analytical result of '97 crop year samples analyzed by '96 calibration equation was more inaccurate than that of '96 crop year samples. The SEP of '96 or '97 crop year samples applying calibration equation derived from '96 plus '97 crop year samples was similar to that of '96 or '97 crop year samples analyzed by '96 or '97 calibration equation, respectively. The SEP of '97 crop year samples analyzed by calibration equation derived from '96 plus '97 crop year samples was more accurate than that of '97 crop year samples analyzed by '96 calibration equation. To improve the analytical inaccuracy caused by the difference of crop year between calibration and prediction samples, we need to include the prediction sample spectra which were different from calibration sample spectra in recalibration sample spectra, and then develop recalibration equation. The NIRS can apply to analyze burley leaf tobacco, leaf process or tobacco manufacturing process which were required the rapid analytical result.

• Textile Coloration and Finishing
• /
• v.5 no.2
• /
• pp.91-98
• /
• 1993

The silk fabrics were treated with color solution extracted from leaf of Camellia. The depression effect of destruction and yellowing of silk treated with color solution, shift of UV-VIS spectra of color solution, color difference of silk fabrics by dyeing with acid dyes and drycleaning fastness of silk treated with color solution were studied. UV-VIS spectra appeared to hypsochromic shift by irradiation. The decrease of tensile strength and the elongation of the silk treated with color solution showed depressed but those of untreated silk increased by irradiation. The yellowness index of silk treated with color solution showed a little change by irradiation. The color difference after dyeing with several acid dyes on treated and untreated silk showed not remarkable changes. Dsrycleaning fastness of silk treated by color solution was excellent.

• Preventive Nutrition and Food Science
• /
• v.13 no.3
• /
• pp.241-244
• /
• 2008

Methanol extracts were prepared from Z. schinifolium leaf and successively fractionated with chloroform, butanol, and water. The butanol fraction exhibited the highest antioxidative activities. Therefore the butanol fraction was purified and a chemical structure was identified by $^1H-^{13}C-NMR$ spectra, and FT-IR. The isolated antioxidative substance was identified as quercitrin.

• Journal of Korean Society of Steel Construction
• /
• v.12 no.1 s.44
• /
• pp.103-110
• /
• 2000

The suspension bridge is divided by an earth anchor and a self-anchor type according to the anchorage type. This study is to evaluate the dynamic effect of moving vehicles to suspension bridges. The results were presented with the dynamic magnification factor (DMF) by the effect of vehicle speed and weight according to the anchorage type. The vehicle model has 6 degrees of freedom to idealize nonlinear multi-leaf suspensions and elastic tires of tractor-trailer. The bridge was modelled with the 3-dimensional frame element and 3-dimensional elastic catenary cable element. The condition of deck surface is considered using the actual road spectra.

• Asian Journal of Atmospheric Environment
• /
• v.7 no.1
• /
• pp.1-7
• /
• 2013

To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.

• Textile Coloration and Finishing
• /
• v.21 no.1
• /
• pp.10-20
• /
• 2009

The objective of this study is to investigate the efficacy of leaf powder colorants as substitutes for traditional fresh juice extract dyeing. Three kinds of leaf powder colorants were prepared by freeze drying method with or without deep freezing as pre-treatment: one powder colorant from fresh leaf juice with deep freezing; two kinds of powder colorant from fresh leaves with and without deep freezing. Their dyeing properties and storage stabilities were studied and compared with the traditional fresh juice extract dyeing. The presence of indigo in the powder colorants was confirmed by UV/Visible absorption spectra. They showed absorption peak at 602nm which was same with indigo absorption peak. Dyeing was done at low temperature around 6$^{\circ}C$. All three powder colorants produced B colors on silk fabrics, showing similar color to the one dyed traditionally with fresh juice extract. The powder colorants from leaves gave higher color strength than the powder from leaf juice. The powder colorant prepared from leaves with deep freezing was the most stable for long term storage as its color and color strength were not changed after 360 days. So, this was used for further dyeing to study the effects of concentration and repeat dyeing on color strength and colorfastness. Fastnesses to dry cleaning and rubbing were fairly good above 4 rating. Further study is needed to improve light fastness. It was concluded that the leaf powder colorant with deep freezing could be used as a substitute for traditional juice extract dyeing at all seasons.

• The Korean Journal of Food And Nutrition
• /
• v.18 no.4
• /
• pp.367-372
• /
• 2005

Antimicrobial effects of the extracts from Castanea crenata leaf were investigated. The antimicrobial effects of methanol extract (8 mg, 20 mg) of 0.2 g and 0.5 g. eq. of Castanea crenata leaf was stronger than that of 0.65 mg of benzoic acid against Gram(+) bacteria such as Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Leuconostoc mesenteroides and Bacillus subtilig and Gram(-) bacteria such as Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. Growth inhibition of various microorganisms was observed in Castanea crenata leaf, therefor the Castanea crenata leaf were solvent fractionated. The ethyl acetate-soluble acidic and phenolic fraction were showed remarkable antimicrobial activity against microorganisms tested. The acidic fraction was purified with silica gel adsorption column chromatography, Sephadex LH-20 column chromatography and HPLC, subsequantly. The antimicrobial active substance isolated from the acid fraction of Castanea crenata leaf was characterized as stigmast-5-en-3-ol($\beta$-sitosterol) by MS and NMR analysis.

• Applied Biological Chemistry
• /
• v.9
• /
• pp.1-7
• /
• 1968

The action Spectra for violaxanthin de-epoxidation and zeaxanthin expoxidation in New Zealand spinach leaf segments Tetragonia expansa, were determined at equal incident quanta of $2.0{\times}10^{15}$ quanta $cm^{-2}$ $second^{-1}$. The action spectrum for de-epoxidation had major peaks at approximately 180 and 648 nm. Blue light was slightly more effective than red light and little activity was observed beyond 700 nm. The action spectrum for epoxidation showed major peaks at around 441 and 670 nm. Blue light was more effective than red light and light beyond 700 nm showed definite activity. The net result of de-epoxidation and epoxidation is a cyclic scheme, the violaxanthin cycle, which consumes $O_2$ and photoproducts. The action spectra indicate that the violaxanthin cycle is more active m clue than in red light and therefore could accout for $O_2$ uptake stimulated by blue light. The differences between the action spectra for de-epoxidation suggest that possibly two photosynthetic systems are involved. It was suggested that the violaxanthin cycle may functional a pathway for the consumption of excess photoproducts generated in blue light or the conversion of these photoproducts to other forms of energy.