• Title/Summary/Keyword: 한국지지

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Pollination study of Euphorbia helioscopia (Euphorbiaceae) (대극과 등대풀의 수분연구)

  • Kim, Deog-Il;Park, Ki-Ryong
    • Korean Journal of Plant Taxonomy
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    • v.44 no.4
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    • pp.281-287
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    • 2014
  • The present study was conducted to understand the growth pattern, pollinators and their frequency of visits of Euphorbia helioscopia population which is located at Tongyoung areas in Korea. The vegetative parts of the species grow early in March, and flowering begins in the middle of the month, and pollination was completed at the mid of April. As a typical form of early spring type, the fruits of E. helioscopia were matured between early in April and May, and the upper parts of plants were disappeared between May and June. During the blooming season about 11 insects species which belong to Diptera, Hymenoptera, Coleoptera and Heteroptera were the most common groups found on this plants. Among them the species of Diptera are the most dominant pollinators for E. helioscopia which is concordant to previous reports in Euphorbia species. Despite of significant numbers of insect visitors in Euphorbia species being reported, E. helioscopia attracts only 11 insect species in study areas, and the paucity of species probably associates with the insect fauna in Tongyoung areas or typical patterns of early spring bloomer of Euphorbias. We observed majority of Diptera species to visit in the morning, and the frequency of visit decreased in the afternoon. Thus, it suggests that the visiting activity of Diptera species is not associated with the temperature increase which was reported in Euphorbia species. However, the number of the cyathium during the blooming season is likely to be related to the frequency of visit of pollinators in E. helioscopia.

$^{230}$ Th/$^{234}$ U disequilibrium dating of fracture-filling carbonate veins from the Ipsil and Janghangri fault zones, Gyeongju, Korea by multiple collector inductively coupled plasma mass spectrometry (다검출기 유도결합 플라즈마 질량분석기를 이용한 경주 입실, 장항리 단층 파쇄대 충진 탄산염암 맥의 $^{230}Th/^{234}U$ 비평형 연대측정)

  • 정창식;최만식;김현철;임상복
    • The Journal of the Petrological Society of Korea
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    • v.10 no.3
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    • pp.148-156
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    • 2001
  • We report $^{230}Th/^{234}U$ disequilibrium ages of fracture-filling carbonate veins from the Ipsil and Janghangri fault zones, Gyeongju, Korea by multiple collector inductively coupled plasma mass spectrometry. The U and Th fraction was extracted from totally dissolved samples by rapid and convenient coprecipitation and ion exchange chemistry. The recovery was around 80% for Th and 70% for U. The $^{234}U/^{238}U,\;^{230}Th/^{232}Th$ ratios were analysed for this preconcentrated fraction and the U/Th ratio was directly analysed for untreated sample solution. The $^{234}U-^{230}Th$ system is in secular equilibrium for the Ipsil carbonate samples, supporting previously reported ESR ages. The detrital-corrected $^{230}Th/^{234}U$ age of the Janghangri carbonate samples is $48\pm$41 ka, which constrains the minimum age of the fracture zone.

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Needs of Hospice Care and Quality of Life for Cancer Patients (암환자의 호스피스 간호 요구와 삶의 질)

  • Seo, In-Sun;Shin, Mi-Hwa;Hong, Se-Hwa
    • Journal of Hospice and Palliative Care
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    • v.13 no.2
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    • pp.89-97
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    • 2010
  • Purpose: This study investigated the relationship between the needs for hospice care and quality of life in cancer patients. Methods: Data were collected from 127 cancer patients hospitalized at a university hospital in Chonbuk between October, 2006 to March, 2007. Two instruments were used: cancer patients' need for hospice care, developed by Kang and Kim and quality of life developed by Tae et al. Results: The mean scores were 3.11 out of 4 for hospice care needs, and 5.25 out of 10 for quality of life. The correlation between needs for hospice care and quality of life was moderate and negative (r=-0.395, P<0.01). Among the four groups of needs, physical need was the most strongly correlated with quality of lifer (r=-0.388, P<0.01). The need for hospice care was significantly different according to participants' religion (t=6.02, P<0.05), and duration of disease (F=3.45, P< 0.05). Quality of life was significantly different according to participants' monthly income (F=3.38, P<0.05). cancer stage (F=8.10, P<0.01) and chemotherapy (t=6.09, P=0.015). Conclusion: The results suggested that the cancer patients' hospice care needs should be answered in order to improve their quality of life. While doing so, participants' characteristic need should also be considered.

Changes in Life-sustaining Treatment in Terminally Ill Cancer Patients after Signing a Do-Not-Resuscitate Order (심폐소생술금지 동의 전·후 말기암환자의 연명치료 변화)

  • Kim, Hyun A;Park, Jeong Yun
    • Journal of Hospice and Palliative Care
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    • v.20 no.2
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    • pp.93-99
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    • 2017
  • Purpose: This study investigated changes in life-sustaining treatments in terminally ill cancer patients after consenting to a do-not-resuscitate (DNR) order. Methods: Electronic medical records were reviewed to select terminally ill cancer patients who were treated at the oncology unit of the Asan Medical Center, a tertiary hospital in South Korea and died between January 1, 2013 and December 31, 2013. Results: The median (range) age of the 200 patients was 59 (22~89) years, and 62% (124 persons) were male. Among all patients, 83.5% were aware of their medical condition, and 47.0% of the patients had their DNR order signed by their spouses. The median of the patients' hospital stay was 15 days, and time from admission to DNR decision was 10 days. After signing a DNR order, 35.7~100% of the life-sustaining treatments that had been provided at the time of the DNR decision making were administered. The most commonly discontinued interventions were transfusion (13.5%), blood test (11.5%) and parenteral nutrition (8.5%). Conclusion: It is necessary to define the scope of life-sustaining treatments for DNR patients. Treatment guidelines should be established as well to secure terminal patients' death with dignity after their consent to a DNR order, thereby avoiding meaningless life-sustaining treatments and allowing administration of active terminal care interventions.

Fabrication of TiO2 Impregnated Stainless Steel Fiber Photocatalyts and Evaluation of Photocatalytic Activity (TiO2 담지 스테인리스 강 섬유 광촉매 제조 및 광촉매 활성 평가)

  • Song, Sun-Jung;Kim, Kyoung Seok;Kim, Kyung Hwan;Li, Hui Jie;Cho, Dong Lyun;Kim, Jong Beom;Park, Hee Ju;Shon, Hokyong;Kim, Jong-Ho
    • Applied Chemistry for Engineering
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    • v.19 no.6
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    • pp.674-679
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    • 2008
  • $TiO_2$ impregnated stainless steel fiber photocatalysts ($TiO_2/SSF$) were fabricated to overcome inherent problems of powdery $TiO_2$ photocatalysts in water treatment. Adhesion strength of the impregnated $TiO_2$ was examined using an ultrasonic-cleaner. Photocatalytic activity was evaluated through decomposition experiment of methylene blue and formic acid. Bactericidal efficiency was evaluated through sterilization experiment of E. Coli and Vibrio Vulnificus. Adhesion strength of the impregnated $TiO_2$ was so high that more than 95% was left over even after the treatment in an ultrasonic-cleaner for 30 min. Methylene blue and formic acid were decomposed as much as 60% and 38% of the initial concentration and more than 99.9% of E. Coli and Vibrio Vulnificus were killed after 1 hour exposure to the prepared photocatalyst under UV irradiation. In the case of decomposition of formic acid, decomposition ratio increased if oxidants were added. Especially the decomposition ratio increased as high as 80% when hydrogen peroxide was added as an oxidant.

A Study on the Reaction Characteristics of Carbon Dioxide Methanation Catalyst for Full-Scale Process Application (이산화탄소 메탄화 공정 적용을 위한 Ni/CeO2-X 촉매의 반응 특성 연구)

  • Lee, Ye Hwan;Kim, Sung Su
    • Applied Chemistry for Engineering
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    • v.31 no.3
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    • pp.323-327
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    • 2020
  • The reaction characteristics of Ni/CeO2-X which is highly efficient at a low temperature was investigated for an application to carbon dioxide methanation process. The CeO2-X support was obtained by the heat treatment of Ce(NO3)3 at 400 ℃ and the catalyst was prepared by impregnation process. The operating parameters of the experiment were the internal pressure of the reactor, the composition of oxygen, methane, and hydrogen sulfide in the inlet gas and the reaction temperature. When Ni/CeO2-X was used for the carbon dioxide methanation reaction, the CO2 conversion rate increased by more than 25% as the pressure increased from 1 to 3 bar. The increase was large at a low reaction temperature. When both oxygen and methane were in the inlet gas, the CO2 conversion rate of the catalyst decreased by up to 16 and 4%, respectively. As the concentration of oxygen and methane increased, the reduction rate of the CO2 conversion rate tended to increase. In addition, the hydrogen sulfide in the inlet gas reduced the CO2 conversion rate by up to 7% and caused catalyst deactivation. The results of this study will be useful as basic data for the carbon dioxide methanation process.

Mesoporous Silica Catalysts Modified with Sulfonic Acid and Their Catalytic Activity on Ring Opening Polymerization of Octamethylcyclotetrasiloxane (술폰산으로 표면개질된 메조기공 실리카 촉매의 제조 및 Octamethylcyclotetrasiloxane 개환중합에서의 촉매 활성)

  • Lee, Yeonsong;Hwang, Ha Soo;Lee, Jiyoung;Lo, Nu Hoang Tien;Nguyen, Tien Giang;Lee, Donghyun;Park, In
    • Applied Chemistry for Engineering
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    • v.31 no.4
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    • pp.383-389
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    • 2020
  • Mesoporous silica solid catalysts modified with sulfonic acid were prepared for cationic ring-opening polymerization of octamethylcyclotetrasiloxane (D4). Two sets of MCM-41 (1.7 and 2.8 nm) and SBA-15 (8.1 and 15.9 nm) with different pore sizes were used as catalyst supports. The surface of silica materials was modified with (3-mercaptopropyl)trimethoxysilane by silylation reaction and oxidized to sulfonic acid. The structures of the prepared catalysts were examined by X-ray diffraction and nitrogen adsorption-desorption. The pore size, specific surface area, and pore volume of the modified solid catalysts decreased slightly. In addition, the modification of the sulfonic acid on the silica surface was confirmed by using infrared spectroscopy and nuclear magnetic resonance spectroscopy. To observe the effect of the particle size on the catalytic activity, it was observed with a scanning electron microscope. The catalysts were used to synthesize PDMS through a ring-opening polymerization of D4, and the conversion and polymerization rate of the polymerization reaction depended on the pore size, specific surface area, particle size, and particle agglomeration of the catalysts. In order for the polymerization rate, the catalyst prepared with SBA-15 of 8.1 nm pore size had the fastest reaction rate and showed the best catalytic activity.

Characteristics of SO2 Oxidation of Pt/TiO2 Catalyst according to the Properties of Platinum Precursor (Platinum Precursor 특성에 따른 Pt/TiO2 촉매의 SO2 산화 반응특성 연구)

  • Kim, Jae Kwan;Park, Seok Un;Nam, Ki Bok;Hong, Sung Chang
    • Applied Chemistry for Engineering
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    • v.31 no.4
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    • pp.368-376
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    • 2020
  • In this study, an analysis on the reaction characteristics of a catalyst using platinum (Pt) as an active oxidation metal catalyst for controlling SO2 was performed. Pt/TiO2 catalyst was prepared by using Pt as various precursor forms on a titania (TiO2) support, and used for the experiment. There was no difference in performance of SO2 oxidation according to Pt valence states such as Pt2+ or Pt4+ on Pt/TiO2, and Pt chloride species such as PtClx reduces SO2 oxidation performance. In addition, as a result of analyzing the valence state of the catalyst before and after the SO2 oxidation reaction by XPS analysis, a decrease in lattice oxygen and an increase in surface chemisorbed oxygen after the SO2 oxidation reaction were confirmed. Therefore it can be suggested that the oxidation reaction of SO2 when using the Pt/TiO2 catalyst is the major one following the Mar-Van Krevelen mechanism where the reaction of lattice oxygen corresponding to PtOx and the oxidation-reduction reaction by oxygen vacancy occur. Overall, it can be confirmed that the oxygen species of PtOx (Pt2+ or Pt4+) present on the catalyst acts as a major active site.

Fabrication of Planar Multi-junction Thermal Converter (평면형 다중접합 열전변환기의 제작)

  • Kwon, Sung-Won;Park, S.I.;Cho, Y.M.;Kang, J.H.
    • Journal of Sensor Science and Technology
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    • v.5 no.4
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    • pp.17-24
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    • 1996
  • Planar multi-junction thermal converters were fabricated for precise measurements of the ac voltage and current by an ac-dc transfer method. A heater and a thermocouple array were fabricated onto a sandwiched membrane, $Si_{3}N_{4}$ (200 nm) / $SiO_{2}$ (400 nm) / $Si_{3}N_{4}$ (200 nm), a thickness of $0.8\;{\mu}m$ and a size of $2{\times}4\;mm^{2}$, which is supported by a surrounding frame. The NiCr heater is located at the center of the membrane vertically. Hot junctions of $48{\sim}156$ pairs of thermocouples (Cu-CuNi44) are located near or onto the heater, and cold junctions are located onto the silicon frame. Output of the thermal converters for 10 mA dc input was $76\;mV{\sim}382\;mV$ dependent on a model, and short term stability of the outputs was ${\pm}5{\sim}15\;ppm$/ 10 min with 5 mA dc input. Responsivity in air was in the range of $3.9{\sim}14.5V/W$. Responsivity of the model BF48 in air which has 48 thermocouples was 2 times or greater than that of 3 dimensional multi-junction thermal converter in vacuum which has 56 thermocouples. AC-DC transfer differences with an input of 10 mA or less were less than ${\pm}1\;ppm$ in the frequency range from 5 Hz to 2 kHz, and about $2{\sim}3\;ppm$ at 5 kHz and 10 kHz.

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The Effect of Good and Bad Luck on Attention to Background versus Object: An Exploratory Study (행운과 불운이 배경 대 대상에 대한 주의에 미치는 효과: 탐색적 연구)

  • Lee, Byung-Kwan;Lee, Guk-Hee
    • Science of Emotion and Sensibility
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    • v.18 no.3
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    • pp.35-48
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    • 2015
  • It is frequently found in daily life that people who experience good luck as lottery winners try to improve their background (e.g., home, car) but it has not been empirically validated why they do that. Present research attempts to explore the prediction that people who experience good luck expand the scope of attention to background and those who undergo bad luck shrink the scope of attention to adjacent objects. Findings from Experiment 1a indicate that participants who experienced good luck (won the rock-paper-scissors game) paid more attention to background and performed worse in the "find the hidden picture" (below FHP) task while those who underwent bad luck (lost the rock-paper-scissors game) paid more attention to objects, leading to better performance in the FHP task. It is also found in Experiment 1a that, if people washed their hands after experiencing good or bad luck, the opposite result occurred. Experiment 1b confirmed that the rock-paper-scissor game manipulated good and bad luck successfully and did not influence self-control. Experiment 2 shows that people who strongly believe in good luck performed poorly in FHP task while those who do not believe in good luck performed well in FHP task. Overall, three experiments support the proposed research hypotheses. Implications of the study findings for cognitive psychology and related fields including consumer and sports psychology are discussed.