• KIEE International Transactions on Electrophysics and Applications
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• v.3C no.6
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• pp.216-219
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• 2003

A new class of carbosiloxane dendrimer (G4-48PyP) terminated with 4-pyridylpropano I was synthesized and its possible application to functional thin films was examined through metal complexation and Langmuir-Blodgett (LB) technique. The highly concentrated periphery pyridyl groups of G4-48PyP were exposed on aq. aluminum ions at the air-water interface. The monolayers showed stability up to ca. 50 mN/m of surface pressure. When the subphase became acidic or alkaline, the monolayers changed to condensed phase. The presence of aluminum ions also caused reduction of the molecular area. The macroscopic images of the monolayers were monitored by Brewster angle microscopy (BAM) and only the images of dendrimer aggregates could be observed after the monolayer collapse. The surface images of the monolayer LB film were scanned by atomic force microscopy (AFM). The convex structures of single and aggregate molecules were directly observed. The structures of Langmuir-Blodgett (LB) films were characterized by FT-IR, UV-Vis, and X-ray photoelectron spectroscopy (XPS). The UV-Vis spectrum of the aluminum ion-complexed LB film showed additional band around 670nm, which was not found in the spectra of dendrimer itself or aq. aluminum ions. XPS spectra also supported the incorporation of aluminum ions into the LB films.

• Korean Journal of Medicinal Crop Science
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• v.5 no.2
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• pp.113-118
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• 1997

Phytochemical analysis on rice bran and its pitch was performed by the tool of TLC, UV- and IR-spetroscopy, so that it was found that they contained ${\gamma}-oryzanol$ and free sterol. GC-MS analysis of free sterol revealed that it was composed of ${\beta}-sitosterol$, campesterol and stigmasterol. Successive phytochemical analysis of ${\gamma}-oryzanol$ revealed that it was composed of ferulic acid ester of triterpene and sterol, respectively. Triterpene moieties of ${\gamma}-oryzanol$ were identified as follows: cycloartanol, cycloartenol, 24-methylenecycloartanol and unknown triterpene; And sterol moieties were found to be identical with free sterols. In addition, characteristic absorption band in UV spectrum (220-340 nm) was exclusively due to ${\gamma}-oryzanol$. Thus, it was suggested that rice brans of nearly all species of Oryza sativa can be quantitatively analyzed by UV absorption spectrometry, even when water soluble pigments was contained in the rice bran.

• Conservation Science in Museum
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• v.14
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• pp.81-89
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• 2013

This study concerns UV-Vis spectrophotometry and 3D-fluorescence spectrophotometry analysis of textile parts of blue and green tones dyed with indigo of blue tone and turmeric, gardenia, goldthread and amur cork tree of yellow tone. In order to verify whether the kinds of textiles affected analysis result of each dye, silk and cotton textile samples were produced. According to the analysis of the degree of reflection of UV-Vis spectrophotometry, unique reflection spectrum of indigo appeared regardless of the kinds of textiles when they were dyed with indigo. As for textiles of green tone, the 3D-fluorescence spectroscopic analysis result showed that unique spectrums of yellow dyes, turmeric, goldthread and amur cork tree appeared regardless of the kinds of textiles but the fluorescence spectrums of gardenia and indigo did not appear.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.109-116
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• 1996

The relationship between antioxidant activities and physicochemical properties of several fractions obtained from freeze-dried (FD) coffee were investigated. The nine kinds of fraction were consecutively extracted from FD coffee with solvents in increasing order of polarity, and the higher polarity of the solvent the higher extraction yield of the fraction. The antioxidant activities of the fractions were determined by Rancimat and oven test on edible oils. The antioxidant activities of the fractions increased in the order of acetone>ethanol>methanol>50% methanol/water>water fraction, and the antioxidant activities of them were higher on lard than on soybean oil. The antioxidant activity of each fraction was strongly related to the contents of total phenol, total nitrogen content and acidity, whereas color intensity, reducing power, carboxylic acid content showed little contribution to the activity. All fractions had three peaks maxima at 208, 275 and 324 nm on UV-visible spectra, but the only one at 324 nm was linealy proportional to the antioxidant activities of the fractions.

• Journal of Practical Agriculture & Fisheries Research
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• v.22 no.1
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• pp.55-63
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• 2020

This study aimed to investigate responses of plant growth and photosynthesis to different kinds of covering materials with selective light transmit for red leaf lettuce (Lactuca sativa L.). Experimental pot design was attached UV blocking filter, red filter, blue filter, and green filter. The kinds of covering materials showed significant results for plant growth especially control, UV blocking filter, and red filter. The photosynthetic rate and anthocyanin content of red leaf lettuce were higher in control and UV blocking filter than others. The quality of red leaf lettuce was low in red, green, and blue film treatments because of too low anthocyanin content.

• BMB Reports
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• v.29 no.1
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• pp.32-37
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• 1996

The cysteine 43, potentially important in the activity of O-acetylserine sulfhydrylase (OASS) from Salmonella typhimurium, has been changed to serine. This mutant enzyme (C43S) has been studied in order to gain insight into the structural basis for the binding of inhibitor, substrate and product. UV-visible spectra of C43S exhibit the same spectral change in the presence of OAS as that observed with wild type enzyme, indicating C43S will form an ${\alpha}$-aminoacrylate Schiff base intermediate. At pH 6.5, however, the deacetylase activity of C43S is much higher than wild type enzyme indicating that cysteine 43 plays a role in stabilizing the ${\alpha}$-aminoacrylate intermediate. The fluoroscence spectrum of C43S exhibits a ratio of emission at 340 to 502 nm of 16.9, reflecting the lower fluorescence of PLP and indicating that the orientation of cofactor and tryptophan are different from that of the wild type enzyme. The emission spectrum of C43S in the presence of OAS gives two maxima at 340 and 535 nm. The 535 nm emission is attributed to the fluoroscence of the ${\alpha}$-aminoacrylate intermediate. The visible circular dichroic spectrum was similar to wild type enzyme, but the negative effect observed at 530~550 nm and the molar ellipicity values for the mutant are decreased by about 50% compared to wild type enzyme. The circular dichroic and fluoroscence studies suggest binding of the cofactor is less asymmetric in C43S than in the wild type enzyme.

• Korean Journal Plant Pathology
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• v.14 no.3
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• pp.191-202
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• 1998

About 300 actinomycetes were isolated from two forest and one sea-shore soil and tested for inhibitory effects on mycelial growth of six plant pathogenic fungi Magnaporthe grisea, Alternaria mali, Colletotrichum gloeosporioides, Phytophthora capsici, Fusarium oxysporum f. sp. cucumerinum, and Rhizoctonia solani. Among 300 actinomycetes tested, only 16 actinomycetes showed the antifungal activity against the test fungi. Isolate NH 50 was selected for production and purification of antifungal antibiotic substances. Actinomycete isolate NH 50 displayed the broad antifungal spectra against 11 plant pathogenic fungi. To identify actinomycete isolate NH 50, cultural characteristics on various agar media, diaminopimelic acid type, and morphological characteristics by scanning electron microscopy were examined. As a result, actinomycete isolate NH 50 was classified as a rare actinomycete that had LL-DAP type and did not produce spores. After incubation of isolate NH 50 in yeast extract-malt extract-dextrose broth, antifungal compound NH-B1 that inhibited mycelial growth of some plant pathogenic fungi was purified from the methanol eluates of XAD-16 resins by a series of purification procedures, i.e., silica gel flash chromatography, C18 flash chromatography, Sephadex LH-20 column chromatography, silica gel medium pressure liquid chromatography (MPLC), C18 MPLC, and high pressure liquid chromatography (HPLC). UV spectrum and 1HNMR spectrum of antifungal compound NH-B1 dissolved in methanol were examined. The antibiotic NH-B1 showed the major peaks at 230 and 271.2nm. Based on the data of 1H-NMR spectrum, NH-B1 was confirmed to be an extremely complex polymer of sugars called polysaccharides. The antibiotic NH-B1 showed strong antifungal activity against Alternaria solani and Cercospora kikuchi, but weak activity against M. grisea.

• Korean Journal of Materials Research
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• v.15 no.8
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• pp.543-547
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• 2005

Organic electroluminescence devices were made from 1,4-bis-(9-anthrylvinyl)benzene (AVB) and 1,4-bis-(9-aminoanthryl)benzene (AAB) anthracene derivatives. Device structure was ITO/AVB/PANI(EB)/Al (multi-layer device) and ITO/AAB:DCM/Al(single-layer device). In these devices, AVB, polyaniline(emeraldine base) (PANI(EB)) and AAB were used as the emitting material. 4-(dicyanomethylene)-2-methyl-6-p-(dimethylamino)styryl-4H -pyran(DCM) was used as red fluorescent dopant. We studied change of fluorescence wavelength with concentration of DCM doped in AAB. The ionization potential (IP) and optical band gap (Eg) were measured by cyclic voltammetry and UV-visible spectrum. We compared with difference of emitting wavelength between photoluminescence and electroluminescence spectrum. In case of the multi-layer device, PANI and AVB EL spectra have similar wave pattern to each PL spectrum and when PAM and AVB were used at the same time, and multi-layer device showed that a balanced recombination and radiation kom PANI and AVB. In case of the single-layer device, with the increase of DCM concentration, the blue emission decreases and red emission increases. This indicates that DCM was excited by the energy transfer from AAB to DCM or the direct recombination at the dopant sites due to carrier trapping, or both. The device with $1.0wt\%$ DCM concentration gave white light.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.297-301
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• 2003

An inhibitor of squalene synthase, a key enzyme in the cholesterol biosynthetic pathways and a target for improved agents to lower plasma levels of low-density lipoprotein, was sequentially purified from Curcuma longa by acetone extraction, silica gel column chromatography, and sephadex LH-20 column chromatography. Active compound, YUF-01, was successfully purified and analyzed as $C_{20}H_{21}O_6$ by electron ionization mass spectrum. Through $^1H-NMR$ and $^{13}C-NMR$ analyses, YUF-01 was identified as curcumin, which showed strong inhibition of squalene synthase.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.1
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• pp.1-7
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• 2006

The spectroscopic characteristics of Pu (III, IV, V, VI) in the HCl media were investigated by measuring Pu oxidation states using a UV-Vis-NIR spectrophotometer (400-1200 nm) after adjusting Pu oxidation states with oxidation/reduction reagents. Pu in stock solution was reduced to Pu(III) with $NH_2OH$ HCl, and oxidized to Pu(IV) and Pu(VI) with $NaNO_2$ and $HClO_4$, respectively. Also, Pu(V) was adjusted in the Pu(VI) solution with $NH_2OH$ HCl. The major absorption peaks of Pu (IV) and Pu(III) were measured in the 470 m and 600 nm, respectively. The major absorption peaks of Pu (VI) and Pu(V) were measured in the 830 nm and 1135 nm, respectively. There was not found to be significant changes of UV-Vis absorption spectra for Pu(III), Pu(IV) and Pu(VI) with aging time, except that an unstable Pu(V) immediately reduced to Pu(III).