• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.3
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• pp.255-263
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• 2006

Vol-oxidizer is a device to convert $UO_2$ pellets into $U_3O_8$ powder and to feed a homogeneous powder into a Metal Conversion Reactor in the ACP(Advanced Spent Fuel Conditioning Process). In this paper, we propose a design model of the vol-oxidizer, develop the new vol-oxidizer with a capacity of 20 kg HM/batch in $UO_2$ pellets, and conduct a verification for the device. Design considerations include the internal structure, the capacity, the heating position of the device, and the size. The dimensions of the new vol-oxidizer are decided by the design model. We determine a permeability test of the $U_3O_8$ measuring the temperature distribution, and the volume of $UO_2$ and $U_3O_8$. We manufactured the new vol-oxidizer for a 20 kg HM/batch in $UO_2$ pellets, and then analyzed the characteristics of the $U_3O_8$ powder for the verification. The experimental results show that the permeability of the $U_3O_8$ throughout mesh enhance more than old vol-oxidizer, the oxidation time takes only 8 hours when compared with the 13 hours of the old device, and the average distribution of particle size is $40{\mu}m$. The capacities of new vol-oxidizer for a 20 kg HM/batch in $UO_2$ pellets were agree well with the predictions of design model.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.612-617
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• 2008

Tetrodotoxin (TTX) analogues were first determined from the liver extracts of puffer fish, Takifugu niphobles, by LC/MS with Hydrophilic Interaction Liquid Chromatography (HILIC). In total, 7 TTX analogues were detected within 20 minutes as follows; 5,6,11-trideoxyTTX (34.0%, 1,029.6 nmol/g), 6,11-dideoxyTTX (29.3%, 887.6 nmol/g), TTX (22.1%, 667.8 nmol/g), 4,9-anhydro-TTX (11.2%, 339.3 nmol/g), 11-deoxyTTX＋5-deoxyTTX (2.6%, 78.6 nmol/g), and 4-epiTTX (0.8%, 23.6 nmol/g). Mouse toxicity of diluted liver extracts showed the highest toxicity at pH 3 (8.7 MU/mL) and decreased, as increasing pH, to 1.4 MU/mL at pH 10. At acidic (pH 5) and neutral conditions (pH 7), mouse toxicity of liver extracts (79 MU/mL) decreased slowly, as increasing temperature from $80^{\circ}C$ to $115^{\circ}C$, and time until 1 hour; in contrast, at the akaline condition (pH 9), the toxicity decreased rapidly to the more than half within 10 minutes. Individual toxicity of the fillet of T. niphobles were between $43.2{\sim}106.7$ MU, and $64{\sim}78%$ of its toxicity was eluted to soup when boiled with 3 volumes of water during 10 minutes.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.629-639
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• 2000

The study was carried out to compare the antioxidant activities of products from caramel-type-browning reaction of xylose(XY), glucose(GL), sucrose(SU), glucose + citric acid (GLCA), glucose + sodium citrate(GLSC), glucose + glycine(GLGC) heated at 80, 120 or 140$^{\circ}C$ for 24 hr. 1. The hydrogen donating ability (HDA) of browning reaction products was generally enhanced as the browning temperature and time increased. The HDAs of the browning reaction products heated at 80$^{\circ}C$ for 24 hr were in the order of GLSC (0.387) > GLSC (0.362) > GLCA (0.301) > GL (0.299) > XY (0.290) > SU (0.281). But they were in the order of GLSC (0.543) > SU (0.328) > GL (0.309) > GLGC (0.325) > XY (0.298) > GLCA (0.275) under the condition of heating at 140$^{\circ}C$ for 24 hr. 2. The antioxidant activities of the anhydrous ethanol extracts of the browning mixtures were inferior to that of TBHQ as measured in com oil, but SU was superior to tocopherol in its antioxidant activity. All the browning mixtures showed antioxidant activities when heated at 80$^{\circ}C$; however, only SU and GLCA showed the activites at 120 or 140$^{\circ}C$. And the antioxidant activity of the SU extract was higher than that of TOCO. The antioxidant activities of the ethanol extracts were in the order of TBHQ > GLCA > GLGC > TOCO > SU > XY > GL > GLSC > control at 80$^{\circ}C$, TBHQ > SU > TOCO > GLCA > control > GLSC> XY > GL > GLGC at 120$^{\circ}C$, and TBHQ > SU > TOCO > GLCA > control > GLSC > GLGC > XY > GL at 140$^{\circ}C$.

• Journal of Bio-Environment Control
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• v.29 no.4
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• pp.428-439
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• 2020

This study was carried out to investigate the effect of PO film on the increase of crop yield and energy saving through PO and PE film greenhouse application and comparison test. As a experimental greenhouse, two single span greenhouses (1-1 W) and two double span greenhouses (1-2 W) were used. During winter season, PO film (0.15 mm outer layer, 0.10mm inner layer) was used as a covering material of greenhouse in double layers for double-span (B15) and single-span(B21), and PE film used for double-span (B15), and single-span (B23) as a control. The experimental vegetable was tomato(Solanum lycopersicum L.) cultivated in soil and the cultivar of that was 'Happiness'. That was cultivated from December 3, 2019 to April 30, 2020. The temperature at night inside the greenhouse was maintained at 15℃, and the side and roof windows were opened to maintain 23 ~ 24℃ during the day. As a result, this study showed that the yield in single-span greenhouse(B21) covered with a PO film increased 20% and that in double-span greenhouse (B16) increased by 9% compared to the greenhouse covered with a PE film (B23, B15). Fuel consumption of the single-span greenhouse (B21) with the cover of PO film was reduced by 12.4% and that of double-span greenhouse was done by 11.5% compared to that of the PE film greenhouse (B23, B15) without any difference between them in growing state.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.123-129
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• 1991

The skipjack and Alaska pollack meat were packed in square No. 3B can, and thermally processed at $121.1^{\cir}C$ so far as to reach Fo values of 5, 10 and 20, respectively. Also the another samples which were heated at $98^{\cir}C$ for 30 minutes were prepared. We have examined the changes of nitrogenous extractives and texture by thermal processing at high temperature in both fish meats. Moisture contents of both fish meats decreased slightly with the increasing of Fo values. When the samples were heated at $98^{\cir}C$ and $121.1^{\cir}C$, pH and VBN contents increased markedly in both fish meats; increasing ratio of pH and VBN contents in skipjack meat was larger than those of Alaska pollack meat. Histamine were detected in concentration of 6.1mg/100g, 0.1mg/100g in raw skipjack and Alaska pollack meat, 8.2mg/100g, 0.1mg/100g in Fo 20 samples of these fish meats, respectively. The contents of total free amino acids in skipjack and Alaska polack meat were 984.8mg/100g, 282.3mg/100g, and these total contents decreased slightly with increasing of Fo values. Little changes were observed in free amino acid composition, but only His, Tau, Ala in skipjack meat and Tau in Alaska pollack meat decreased significantly by heat treatment. Also the degredation of IMP were Proceeded during Preparation and heat treatment of samples, and TMAO changed into TMA almost equivalently. In changes of textures, as compared with heating of 98t for 30 minutes; Fo 5 heat treatment became more softened these fish meats.

• Progress in Medical Physics
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• v.16 no.1
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• pp.16-23
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• 2005

The objective of this study was to construct multi-element ultrasound applicators for the treatment of gynecologic cancer with high dose rate brachytherapy. For the treatment of uterus, piezo-ceramic crystal transducer (PZT -5A) with outer diameter of 4 mm, wall thickness of 1.3 mm, and length of 24.5 mm was selected. For the treatment of cervix or vagina, it should be possible to insert the applicator into the vagina. Thus, a cylindrical PZT -8 material with outer diameter of 24.5 mm, wall thickness of 1.3 mm, and length of 15.2 mm was selected. The operating frequencies determined by vector impedance measurement were 3.2 MHz for the PZT 5A cylinder (OD=4 mm) and 1.7 MHz for the PZT -8 cylinder (OD: 24.5 mm). The ratios of generated acoustic output power to applied electric power were 33% and 61% for the tandem type crystal and the cylinder type crystal, respectively. The radiated acoustic pressure fields from both transducers were calculated using a Matlab code and measured in water using hydrophone. There was good agreement between measured and calculated acoustic pressure field distribution. For a tandem type transducer, the calculated acoustic pressure field decreased from 0.023 MPa at 10 mm to 0.010 Mpa at 30 mm, the reduction of 57%. For the cylinder type transducer which will be used for the treatment of vagina showed 78% reduction at 15 mm and 66% at 25 mm as compared to values at 5 mm from the surface. Based on the characteristics of the transducers, this study demonstrated the possibility of using the crystals as a heating source. Finally, a 3-element and 4-element prototype applicators were constructed. The 3-element applicator is 75 mm long and 4 mm thick and will be used for the treatment of uterus. The 4-element applicator is 61 mm long and 24.5 mm thick and will be used for the treatment of vagina. Using these applicators, it is possible to generate enough power to increase temperature to therapeutic level.

• Economic and Environmental Geology
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• v.49 no.2
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• pp.77-88
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• 2016

Chrysotile is a 1:1 sheet silicate mineral belonging to serpentine group. It has been highlighted studies because of uses, shapes and structural characteristics of the fibrous chrysotile. However, it was designated as Class 1 carcinogen, so high attentions were being placed on detoxification studies of chrysotile. The objectives of this study were to investigate changes of mineralogical characteristics of chrysotile and to suggest detoxification mechanism of chrysotile by thermal decomposition. Samples for this study were obtained from LAB Chrysotile mine in Canada. The samples were heated in air in the range of 600 to $1,300^{\circ}C$. Changes of mineralogical characteristics such as crystal structure, shape, and chemical composition of the chrysotile fibers were examined by TG-DTA, XRD, FT-IR, TEM-EDS and SEM-EDS analyses. As a result of thermal decomposition, the fibrous chrysotile having hollow tube structure was dehydroxylated at $600-650^{\circ}C$ and transformed to disordered chrysotile by removal of OH at the octahedral sheet (MgOH) (Dehydroxylation 1). Upon increasing temperature, it was transformed to forsterite ($Mg_2SiO_4$) at $820^{\circ}C$ by rearrangement of Mg, Si and O (Dehydroxylation 2). In addition, crystal structure of forsterite had begun to transform at $800^{\circ}C$, and gradually grown 3-dimensionally to enstatite ($MgSiO_3$) by recrystallization after the heating above $1,100^{\circ}C$. And then finally transformed to spherical minerals. This study showed chrysotile structure was collapsed about $600-700^{\circ}C$ by dehydroxylation. And then the fibrous chrysotile was transformed to forsterite and enstatite, as non-hazardous minerals. Therefore, this study indicates heat treatment can be used to detoxification of chrysotile.

• Economic and Environmental Geology
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• v.24 no.2
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• pp.131-150
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• 1991

The Weolseong diatreme was temporally and spatially related to the intrusion of the Gadaeri granite, and was -mineralized by meteoric aqueous fluids. In the Nokdong As-Zn deposit, pyrite, aresenopyrite and sphalerite are the most abundant sulfide minerals. They are associated with minor amount of magnetite, pyrrhotite, chalcopyrite and cassiterite, and trace amounts of Pb-Sb-Bi-Ag sulphosalts. The AsZn ore probably occurred at about $350^{\circ}C$ according to fluid inclusion and compositional data estimated from the arsenic content of arsenopyrite and iron content of sphalerite intergrown with pyrrhotite + chalcopyrite + cubanite. Heating studies of fluid inclusions in quartz indicate a temperature range between 180 and $360^{\circ}C$, and freezing data indicate a salinity range from 0.8 to 4.1 eq.wt % NaCl. The coexisting assemblage pyrite + pyrrhotite + arsenopyrite suggests that $H_2S$ was the dominate reduced sulfur species, and defines fluid parameter thus: $10^{-34.5}$ < ${\alpha}_{S_2}$ < $10^{-33}$, $10^{-11}$ < $f_{S_2}$ < $10^{-8}$, -2.4 < ${\alpha}_{S_2}$ < -1.6 atm and pH= 5.2 (sericte stable) at $300^{\circ}C$. The sulfur isotope values ranged from 1.8 to 5.5% and indicate that the sulfur in the sulfides is of magmatic in origin. The carbon isotope values range from -7.8 to -11.6%, and the oxygen isotope values from the carbonates in mineralized wall rock range from 2 to 11.4%. The oxygen isotope compositions of water coexisting with calcite require an input of meteoric water. The geochemical data indicate that the ore-forming fluid probably was generated by a variety of mechanisms, including deep circulation of meteoric water driven by magmatic heat, with possible input of magniatic water and ore component.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.345-358
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• 2018

In this study, we have performed electron probe micro analyzer (EPMA), X-ray differaction (XRD), inductively coupled plasma spectroscopy (ICP), Fourier transform Raman spectroscopy (FT-Raman), far-infrared (FIR), nuclear magnetic resonance (NMR), and pH-DO Analyses for characterizing medicinal mineralogy aspect of the black tourmaline (Shantung, china), black and pink tourmaline (Minas Geraris, Brazil), black touemaline (Daeyu mine, Korea). In addition, heating effects of the tourmaline sauna as well as the effects of tourmaline powder-added soap on skin troubles have been investigated. It has been revealed that chemical composition of the tourmaline is either high in Fe-, Al-, B-rich types. Ratio of the K-Ca, Na-K, and Fe-B reflects the component change property of solid solution. $CaO/CaO+Na_2O$ and MgO/FeO+MgO ratio show high positive correlation. When tourmaline reacts with distilled water, extended reaction time DO values approximately decrease and it stabilizes at DO = 10. Otherwise, pH values increase until 6 hours and it stabilizes at pH = 8 after 24 hours. Distilled water changes to alkaline when it reacts with tourmaline powder and particles. Tourmaline showed lower absorption spectrum strength and transmittance at short wave, where absorption spectrum wavelength and strength were determined by the content of the composition elements and characteristics of crystallography. Increase of the Fe content has been confirmed to be the cause for the reduction of irradiation. For the chemical composition and spectral property of the tourmaline particle samples, it has been found that Si and Fe contents show positive correlation with Far-Infrared irradiation, while Al and Mg contents show negative correlation. For tourmaline powder, it has been confirmed that $^{17}O-NMR$ FWHM (full width at half maximum) decreases when reacts with distilled water. Tourmaline sauna (approximately $100^{\circ}C$) was found to increase $0.5-1.5^{\circ}C$ of body temperature, average of 12 heartbeat, and 10mg Hg of blood pressure. Tourmaline soap had very good aesthetic effect to skin and was confirmed to have above the average improvements to skin troubles (e.g., allergy or atopy).

• Journal of Food Hygiene and Safety
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• v.30 no.2
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• pp.159-165
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• 2015

The aim of this study was to investigate microbiological contamination levels in the manufacturing company of ginseng products (white and red ginseng). Firstly, the contamination level for ginseng and each stage ginseng were 1.8~4.9 log CFU/g (total bacteria), 1.2~3.0 log CFU/g (coliform), 0.8~4.1 log CFU/g (fungi). However, only Bacillus cereus among pathogenic bacteria was detected from a few sample. The contamination of total bacteria tended to decrease as ginseng was being processing. Therefore, that of finished products (white and red ginseng) showed the lowest contamination level among each stage ginseng sample. That of fungi decreased steadily, although the contamination of fungi has tended to increase right after ginseng was steamed. Secondly, the contamination level for working tools and facilities were $1.7{\sim}4.7log\;CFU/cm^2$ (total bacteria), $0.4{\sim}4.0log\;CFU/cm^2$ (coliform), $0.9{\sim}4.2log\;CFU/cm^2$ (fungi). Especially, washing and peeling machines were higher contamination level. Finally, the contamination level of worker who washed and steamed ginseng was higher than worker who shaped, sorted and stored ginseng. Also, Staphylococus aureus was detected at 0.2~0.7 log CFU/hand on some wokers' hands. These results showed proper heating condition (temperature and time) and tidy manufacturing facility are the most important to avoid developing any microbiological problem of Ginseng Products.