• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.709-714
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• 2005

Antibacterial activities of the freeze-dried bamboo sap dissolved into the water or 50% ethanol were determined and antimicrobial activity of bamboo sap dissolved into distilled water was most strong with 15 mm of the diameter of inhibiting clear zone against Listeria monocytogenes ATCC 19114 among gram positive bacteria tested, but it did not inhibit Bacillus subtilis ATCC 6633 at all, and the sap was most greatly inhibited the growth of Shigella dysenteriae ATCC 9361 among gram negative bacteria with 15 mm of the diameter of inhibiting clear zone. Bamboo sap dissolved into 50% ethanol most strongly inhibited the growth of L. monocytogenes ATCC 19114 and it also inhibited the growth of B. subtilis ATCC 6633 which did not show any with the sap dissolved into distilled water. The sap dissolved into 50% ethanol was most greatly inhibited the growth of S. dysenteriae ATCC 9361 among gram negative bacteria with 23 mm of the diameter of inhibiting clear zone, and it inhibited Vibrio parahaemolyticus WSDH 22, Vibrio vulnilicus ATCC 29307 and Escherichia coli O157 WSDH 54 with 16 mm of the diameter of inhibiting clear zone. However, Both of the saps dissolved in distilled water and 50% ethanol did not showed any inhibition against the lactic acid bacteria of Lactobacillus plantarum KCTC and Lactobacillus brevis KCTC. Most of the tested bacteria were more sensitive to the sap dissolved in 50% ethanol than the sap dissolved in distilled water. The lowest minimum inhibitory concentration of the bamboo sap dissolved into 50% ethanol was 0.6 mg eq./disc with L. monocytogenes ATCC 19114, but that of the sap dissolved into distilled water was 0.8 mg eq./disc with Staphylococcus epidermides ATCC 12228, S. dysenteriae ATCC 9361, L. monocytogenes ATCC 19114, Salmonella typhimurium WSU 2380 and V. parahaemolyticus WSDH 22. In a model food system of the sterilized chocolate milk, antibacterial activities of the sap dissolved into 50% ethanol were relatively stronger than those of the sap dissolved into distilled water and the activities against the bacteria tested were very similar each other. These result suggested the bamboo sap can be used as a natural food preservative.

• Economic and Environmental Geology
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• v.27 no.2
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• pp.147-160
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• 1994

Copper-bearing hydrothermal vein mineralization of the Samsan area was deposited in two stages (I and II) of quartz-calcite-sulfide veins which fill fissures in Cretaceous volcanic and sedimentary rocks of the Gyeongsang basin. The major ore minerals, chalcopyrite and sphalerite, together with pyrite, galena, hematite, and minor sulfosalts, occur with epidote and chlorite as gangue minerals in stage I quartz veins. Chlorite geothermometry, fluid inclusion and stable isotope data indicate that copper ore was deposited mainly at temperatures between $330^{\circ}C$ and $280^{\circ}C$ from fluids with salinities between 12 and 3 equiv. wt % NaCl. Evidence of fluid boiling indicates a range of pressures from ${\leq}100$ to 200 bars bars. Within ore stage I there was an apparent decrease in ${\delta}^{34}S$ values of $H_{2}S$ with paragenetic time, from 8.0 to 2.3 per mil. This pattern was likely achieved through progressive increases in activity of oxygen accompanying boiling and mixing. In the early part of the first stage, the high temperature, high salinity fluids gave way to progressively cooler and more dilute fluids of the late parts in the first stage and of the second stage. There is a systematic decrease in calculated ${\delta}^{18}O_{water}$ values with decreasing temperature in the Samsan hydrothermal system, from values of -86 per mil for early portion of stage I through -5.9 per mil for late portion of stage I to -6.3 per mil for stage II. The ${\delta}D$ values of fluid inclusion waters also decrease with paragenetic time from -76 per mil to -86 per mil. These trends combined with mineral paragenesis and fluid inclusion data are interpreted to indicate progressive cooler, more oxidizing meteoric water inundation of an early exchanged meteoric hydrothermal system.

• Electrical & Electronic Materials
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• v.12 no.7
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• pp.7-11
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• 1999

Fully sealed field emission display in size of 4.5 inch has been fabricated using single-wall carbon nanotubes-organic vehicle com-posite. The fabricated display were fully scalable at low temperature below 415$^{\circ}C$ and CNTs were vertically aligned using paste squeeze and surface rubbing techniques. The turn-on fields of 1V/${\mu}{\textrm}{m}$ and field emis-sion current of 1.5mA at 3V/${\mu}{\textrm}{m}$ (J=90${\mu}{\textrm}{m}$/$\textrm{cm}^2$)were observed. Brightness of 1800cd/$m^2$ at 3.7V/${\mu}{\textrm}{m}$ was observed on the entire area of 4.5-inch panel from the green phosphor-ITO glass. The fluctuation of the current was found to be about 7% over a 4.5-inch cath-ode area. This reliable result enables us to produce large area full-color flat panel dis-play in the near future. Carbon nanotubes (CNTs) have attracted much attention because of their unique elec-trical properties and their potential applica-tions [1, 2]. Large aspect ratio of CNTs together with high chemical stability. ther-mal conductivity, and high mechanical strength are advantageous for applications to the field emitter [3]. Several results have been reported on the field emissions from multi-walled nanotubes (MWNTs) and single-walled nanotubes (SWNTs) grown from arc discharge [4, 5]. De Heer et al. have reported the field emission from nan-otubes aligned by the suspension-filtering method. This approach is too difficult to be fully adopted in integration process. Recently, there have been efforts to make applications to field emission devices using nanotubes. Saito et al. demonstrated a car-bon nanotube-based lamp, which was oper-ated at high voltage (10KV) [8]. Aproto-type diode structure was tested by the size of 100mm $\times$ 10mm in vacuum chamber [9]. the difficulties arise from the arrangement of vertically aligned nanotubes after the growth. Recently vertically aligned carbon nanotubes have been synthesized using plasma-enhanced chemical vapor deposition(CVD) [6, 7]. Yet, control of a large area synthesis is still not easily accessible with such approaches. Here we report integra-tion processes of fully sealed 4.5-inch CNT-field emission displays (FEDs). Low turn-on voltage with high brightness, and stabili-ty clearly demonstrate the potential applica-bility of carbon nanotubes to full color dis-plays in near future. For flat panel display in a large area, car-bon nanotubes-based field emitters were fabricated by using nanotubes-organic vehi-cles. The purified SWNTs, which were syn-thesized by dc arc discharge, were dispersed in iso propyl alcohol, and then mixed with on organic binder. The paste of well-dis-persed carbon nanotubes was squeezed onto the metal-patterned sodalime glass throuhg the metal mesh of 20${\mu}{\textrm}{m}$ in size and subse-quently heat-treated in order to remove the organic binder. The insulating spacers in thickness of 200${\mu}{\textrm}{m}$ are inserted between the lower and upper glasses. The Y\ulcornerO\ulcornerS:Eu, ZnS:Cu, Al, and ZnS:Ag, Cl, phosphors are electrically deposited on the upper glass for red, green, and blue colors, respectively. The typical sizes of each phosphor are 2~3 micron. The assembled structure was sealed in an atmosphere of highly purified Ar gas by means of a glass frit. The display plate was evacuated down to the pressure level of 1$\times$10\ulcorner Torr. Three non-evaporable getters of Ti-Zr-V-Fe were activated during the final heat-exhausting procedure. Finally, the active area of 4.5-inch panel with fully sealed carbon nanotubes was pro-duced. Emission currents were character-ized by the DC-mode and pulse-modulating mode at the voltage up to 800 volts. The brightness of field emission was measured by the Luminance calorimeter (BM-7, Topcon).

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.241-246
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• 2007

Purpose: $[^{11}C]6-OH-BTA-1$ ([N-methyl-$^{11}C$]2-(4'-methylaminophenyl)-6-hydroxybenzothiazole, 1), a -amyloid imaging agent for the diagnosis of Alzheimer's disease in PET, can be labeled with higher yield by a simple loop method. During the synthesis of $[^{11}C]1$, we found the formation of by-products in various solvents, e.g., methylethylketone (MEK), cyclohexanone (CHO), diethylketone (DEK), and dimethylformamide (DMF). Materials and Methods: In Automated radiosynthesis module, 1 mg of 4-aminophenyl-6-hydroxybenzothiazole (4) in 100 l of each solvent was reacted with $[^{11}C]methyl$ triflate in HPLC loop at room temperature (RT). The reaction mixture was separated by semi-preparative HPLC. Aliquots eluted at 14.4, 16.3 and 17.6 min were collected and analyzed by analytical HPLC and LC/MS spectrometer. Results: The labeling efficiencies of $[^{11}C]1$ were $86.0{\pm}5.5%$, $59.7{\pm}2.4%$, $29.9{\pm}1.8%$, and $7.6{\pm}0.5%$ in MEK, CHO, DEK and DMF, respectively. The LC/MS spectra of three products eluted at 14.4, 16.3 and 17.6 mins showed m/z peaks at 257.3 (M+1), 257.3 (M+1) and 271.3 (M+1), respectively, indicating their structures as 1, 2-(4'-aminophenyl)-6-methoxybenzothiazole (2) and by-product (3), respectively. Ratios of labeling efficiencies for the three products $([^{11}C]1:[^{11}C]2:[^{11}C]3)$ were $86.0{\pm}5.5%:5.0{\pm}3.4%:1.5{\pm}1.3%$ in MEK, $59.7{\pm}2.4%:4.7{\pm}3.2%:1.3{\pm}0.5%$ in CHO, $9.9{\pm}1.8%:2.0{\pm}0.7%:0.3{\pm}0.1%$ in DEK and $7.6{\pm}0.5%:0.0%:0.0%$ in DMF, respectively. Conclusion: The labeling efficiency of $[^{11}C]1$ was the highest when MEK was used as a reaction solvent. As results of mass spectrometry, 1 and 2 were conformed. 3 was presumed.