• Clean Technology
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• v.27 no.4
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• pp.332-340
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• 2021

With the recent reinforcement of emission standards, it is necessary to make efforts to reduce NOx from air pollutant-emitting workplaces. The NOx reduction method mainly used in industrial facilities is selective catalytic reduction (SCR), and the most commercial SCR catalyst is the ceramic honeycomb catalyst. This study was carried out to reduce the NOx emitted from steel plants by applying De-NOx catalyst coated on metallic monolith. The De-NOx catalyst was synthesized through the optimized coating technique, and the coated catalyst was uniformly and strongly adhered onto the surface of the metallic monolith according to the air jet erosion and bending test. Due to the good thermal conductivity of metallic monolith, the De-NOx catalyst coated on metallic monolith showed good De-NOx efficiency at low temperatures (200 ~ 250 ℃). In addition, the optimal amount of catalyst coating on the metallic monolith surface was confirmed for the design of an economical catalyst. Based on these results, the De-NOx catalyst of commercial grade size was tested in a semi-pilot De-NOx performance facility under a simulated gas similar to the exhaust gas emitted from a steel plant. Even at a low temperature (200 ℃), it showed excellent performance satisfying the emission standard (less than 60 ppm). Therefore, the De-NOx catalyst coated metallic monolith has good physical and chemical properties and showed a good De-NOx efficiency even with the minimum amount of catalyst. Additionally, it was possible to compact and downsize the SCR reactor through the application of a high-density cell. Therefore, we suggest that the proposed De-NOx catalyst coated metallic monolith may be a good alternative De-NOx catalyst for industrial uses such as steel plants, thermal power plants, incineration plants ships, and construction machinery.

• Korean Chemical Engineering Research
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• v.59 no.1
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• pp.127-137
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• 2021

Air emission charge for nitrogen oxide as a precursor of fine dust has been introduced and implemented within the country from 2020. Therefore, the development of economical combustion technology for NOx reduction has got more needed urgently. This study investigated the air-staging effect as a way to reduce the NOx during combustion of domestic unused forest biomass, recently possible to secure REC (Renewable Energy Certification) as a substitute for overseas wood pellets in a 0.1 MWth circulating fluidized bed combustion test-rig. Operating conditions were comparison with and without air-staging, the supply position of tertiary air (6.4 m, 8.1 m, 9.4 m in the combustor) and variation of air-staging ratio (Primary air:Secondary air:Tertiary air=91%:9%:0%, 82%:9%:9%, 73%:9%:18%). NO and CO concentrations in flue gas, profiles of temperature and pressure at the height of the combustion, unburned carbon in sampled fly ash and combustion efficiency on operating conditions were evaluated. As notable results, NO concentration with air-staging application under tertiary air supply at 9.4 m in the combustor reduced 100.7 ppm compared to 148.8 ppm without air-staging while, CO concentration increased from 52.2 ppm without air-staging to 99.8 ppm with air-staging. However, among air-staging runs, when tertiary air supply amount at 6.4 m in the combustor increased by air-staging ratio (Primary air:Secondary air:Tertiary air=73%:9%:18%), NO and CO concentrations decreased the lowest 90.8 ppm and 66.1 ppm, respectively. Furthermore, combustion efficiency at this condition was improved to 99.3%, higher than that (98.3%) of run without air-staging.

• Proceedings of The Korean Society of Health Promotion Conference
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• 2004.10a
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• pp.17-58
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• 2004

뉴저지주 보건교육/건강 증진정책을 논하기전에 건강증진과 보건 교육사의 뜻을 먼저 기술하기로 한다. 건강증진이란 일상 사회생활과 행동과학의 응용에서 시작하며 교육의 효율적 작전 및 기술, 질병 역학 조사, 개인 및 가족단위 건강 위해 행위 절감, 사회연관 구축망 조성, 그리고 적게는 이웃, 더 나아가 조직체계 및 지역 사회의 네트웍 실시등을 실시한다. 보건교육 및 건강증진 전문가란 ' 전국 보건교육 인증 위원회(NCHEC) ' 에서 채택된 다음 7개 활동 영역에서 개인적, 그룹, 각주단위, 그리고 범 국가적 조직에서 종사하는자로 한다. 개인 및 지역사회 보건 교육 필요성 분석- 계회, 실행, 효율성 평가, 사업 진행 조정, 자문, 컴뮤니케이션 등의 활동범위를 들 수 있다. 공인 보건 교육사(CHES)란 대학 및 대학원에서 보건 교육학 소정의 필수 과목을 이수하고 학.석사 소지자로서 ' 전국 보건 교육 인증 위원회 ' 에서 그 자격을 인정 받고 공인 자격 시험에 합격한자로 한다. 합격자는 자기 성명뒤에 CHES란 칭호를 부치며 매 5년마다 75단위이상 인정된 전문 직업 보수 교육을 받아야 한다. 보건 교육사 고용 분야는 연방, 주, 지방 정부의 보건 교육사(10-15%) 및 건강 증진 전문가로 종사하며; 이들은 지역 사회 조직화, 프로그람 기획, 공공사업 마켓팅, 메디아, 컴뮤니케이션 자질을 갓추어야 하며; 상해 예방, 학교 보건, 지역 사회 영양 실태 향상, 그 외 모든 건강 증진과 질병 예방에 일익을 담당 하여; 의사, 간호사, 약사, 영양사,환경 위생사드의 전문분야종사자들괴 한팀이 되어 지역 사회 보건 사업에 기여한다. 쥬저지 보건 교육사들은 주법령 8조 '||'&'||' 보건행정 표준 시행령 ' 에 따라 포괄적 보건교육/건강증진 프로그램을 개발하여 총체적으로 조절 관장한다. 특희 ' 미국 학술원 의료 연구원 ' 에서 제정한 ' 10대 필수 공중 보건 사업 ' 에 기준을 두고; 1) 개인 및 지역사회 필수 보건 여건 분석 평가, 2) 보건 교육 이론에 따른 사업 계획 설정, 3) 교육 전략과 보건문제 발굴에 따라 일반 대중 대상 보건 교육 실행 (프로그람 기획, 연수 교육, 미디어 캠페인, 공중보건 향상책 옹호), 4) 사업 진행 과정 정리, 그 결과에 대한 영향력과 결과 평가, 5) 프로그램진행, 인사 및 예산관리 참여, 6) 근무향상을 위한 보수교육 프로그램 개발, 7) 보건 의료 업무 종사자 상호 협조성 향상 훈련, 8) 지역 사회자원 밭굴, 9) 적절한 고객 의뢰 체제 시행, 10) 위기 관리 컴뮤니케이션 체제 개발실시, 11) 일반 대중에게 공중 보건 향상 고취, 12) 각종 협력 지원금 신청서 작성 제출, 13) 문화/인종적으로 적절한 시청각 교재 발굴, 15) 질적 및 양적 보건교육/건겅증진책 연구 실시, 16) 비 보험 가담자, 저 보험자, 빈곤자, 이민자 색출 선도, 17) 관활 구역내 상재하는 각 건강증진 프로그램 밝혀 내서 불필요한 중복 회피등이다. 그 외에도 보건 교육사들은 사회 복지 단체인 미국 암 협회, 미국 심장 협회,미국 폐장 협회 등 각종 사회 복지 비영리단체 와 자선 사업 단체들과 긴밀희 협조하거나 그 단체 임직원으로서 건강 증진 사업에 종사한다. 병원 및 의료기관에선 임직원 보수 교육, 환자의 질병 예방및 건강증진 교육, 그리고 의료 사업장내 건장 증진업무에 종사한다. 건강 유지 의료 기관(HMO)에선 예방주사, 정기검진 촉진등을 통한 입원일수 절감, 응급실 사용도 절감등으로 의료비 감축, 삶의질 향상상에 종사한다. 사업장 보건 교육사는 스트레스 관리, 금연 및 흡연 중단선도, 체중 절감, 종업원 건강증진 생활화참여 유치, 컴뮤니케이션 개발, 마켓팅, 질병 예방등에 그 전문 직업적 노하우를 사업체 건강 증진 프로그램 개발에 접목한다. 뉴저지 2010년대 건강 증진책은 5대 목표 설정하여 현재 시행하고 있다. 특이한점은 2001년 9.11사태 이후 연방정부와 주정부의 상당한 예산 지원을 그랜트 지원금 형식으로 받아 연방, 주정부, 지방 정부, 의료 기관등에서 일사 불란하게 생물/화학/방사성 테러에 대비하는데 보건 교육사들은 시민 인지도 향상과 위기관리 컴뮤니케이션 영역에서 활약한다. 총체적인 보건 교육/건강 증진책은 다음 천년간 뉴저지 건강증진 백서와 미연방 정부 건강증진 2010에 준하여 설립한 뉴저지 건강 증진 2010 에 의한다. 그 모델을 보면; 1) 생활 습관 향상으로 위해 행위 절제; 적절한 영양 섭취 와 과체중화 차단 불필요한 투약 절제와 그 관리 흡연 탐익 절감, 금연, 흡연관련 신체/정신적 피해 관리/치료 습관성 약물 중독 조기발견 예방 낙상 예방 폭력, 의도적/비의도적 상해 예방 2) 심장질환, 암, 뇌졸중, 당뇨, 폐염, 인프루엔자등 주사망원인 질병 조기 발견 예방 책 마련; 독감.폐렴 예방 주사 실시 3) 보건 교육 대상과 표적 설정 특히 보건사업 참여 동반자 발굴하여 그 동참과 책임분담 책려; 주. 지방 정부기관, 의료 종사자, 의료 보험 업자, 대학 등 교육 기관, 연구 기관, 교육자, 지방 보건소, 지역 사회 비 영리단체, 종교 단체 및 교역자 등의 참여 촉구., 지역 사회 비 영리단체, 종교 단체 및 교역자 등의 참여 촉구.

• Tunnel and Underground Space
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• v.32 no.6
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• pp.491-501
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• 2022

Bentonite has been proposed as a buffer and backfill material for high-level radioactive waste repository. Under such repository environment conditions, bentonite is subjected to combined thermal, hydrological, mechanical, and chemical processes. This study evaluates the feasibility of applying X-ray CT technology on the characterization of bentonite under hydration conditions using a newly developed testing cell. The cylindrical cell is made of platic material, with a removable cap to place the sample, enabling to apply vertical pressure on the sample and to measure swelling pressure. The hydration test was carried out with a sample made of Gyeonju bentonite, with a dry density of 1.4 g/cm³, and a water content of 20%. The sample had a diameter of 27.5 mm and a height of 34 mm. During the test, water was injected at a constant pressure of 0.207 MPa, and lasted for 7 days. After one day of hydration, bentonite swelled and filled out the space inside the cell. Moreover, CT histograms showed how the hydration process induced an initial increase and later progressive decrease on the density of the sample. Detailed profiles of the mean CT value, CT standard deviation, and CT gradient provided more details on the hydration process of the sample and showed how the bottom and top regions exhibited a decrease on density while the middle region showed an increase, especially during the first two days of hydration. Later, the differences in CT values with respect to the initial state decreased, and were small at the end of testing. The formation and later reduction of cracks was also characterized through CT scanning.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.534-540
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• 2007

In this study, waxy rice starch was chemically modified using phosphorous oxychloride ($POCl_3$, 0.002-0.008%). Then the physicochemical properties of resulting cross-linked waxy rice starches were investigated in order to reduce the steeping time of Yukwa (a Korean oil-puffed rice snack) processing. The swelling powers of the cross-linked waxy rice starch samples were higher than the native waxy rice starch at temperatures above $60^{\circ}C$, and their increases were proportional to the $POCl_3$, concentration. The solubility of the cross-linked waxy rice starch was lower (1.6-3.4%) than the native waxy rice starch (2.7-6.1%). However, the moisture sorption isotherm of the cross-linked waxy rice starch was not significantly different from the native waxy rice starch. The rapid visco analyze. (RVA) pasting temperatures $(65.4-67^{\circ}C)$ of the cross-linked waxy rice starch were lower than those of the native starch $(67^{\circ}C)$. The RVA peak viscosities (287-337 RVU) of the cross-linked waxy rice starch were higher than that of native starch (179 rapid visco units (RVU)), and increased with increasing $POCl_3$ concentration. For the differential scornning calorimeter thermal characteristics, although Tc shifted toward higher temperatures with cross-linking, the To, Tp, and amylopectiin melting enthalpy of the cross-linked waxy rice starch showed no differences compared to the native waxy rice starch. The X-ray diffraction patterns of both the native and cross-linked waxy rice starches showed typical A-type crystal patterns, suggesting that cross-linking mainly occurs in the amorphous regions of starch granules. Therefore, the cross-linking reaction did not change the crystalline region, but altered the amorphous region of the waxy rice starch molecules, resulting in changes of solubility and RVA pasting properties in the cross-linked waxy rice starch. In summary, since cross-linked waxy rice starch has a high puffing efficiency and no browning reaction, it may be applicable for Yukwa processing without a long steeping process.

• The Korean Journal of Nuclear Medicine Technology
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• v.16 no.1
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• pp.91-95
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• 2012

Purpose: In this study, we evaluated the ejection fraction (EF) according to the difference of patient position in Gated Blood Pool (GBP) scan. Material and Methods: The analysis was performed to 80 patients ($51.2{\pm}17.4$ years old) who examined GBP scan in Department of nuclear medicine, National Cancer Center from March 2011 to August 2011. We divided the patients into two groups; one group received conventional position (raise left arm up supine) and supine position (group 1) and the other group received conventional position and left arm back down supine position (group 2). To observe the change EF according to patient position difference, the image was reconstructed and analyzed by Xeleris (GE, USA). We measured body mass index (BMI) of patients. Result: In group 1, EF error less than 3% occurred at a rate of 72.5% (29 of the 40 patients). In group 2, EF error less than 3% occurred at a rate of 79% (32 of the 40 patients). The patient's BMI did not affect ejection fraction. Conclusion: The EF error of left arm back down supine position closer to conventional position than in supine position shows the results.

• Journal of the Mineralogical Society of Korea
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• v.21 no.3
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• pp.313-320
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• 2008

Hectorite was synthesized under hydrothermal conditions and its physicochemical properties have been investigated in terms of temperature, pH, and organic agent to observe the change of doll basal spacing. The IR, CEC, MB, swelling volume and specific surface area of the hectorite were measured for the characterization. The solid/liquid ratio of hectorite to distilled water before mixing with other materials was also determined for its use as a multi-functional material. The $d_{001}$ basal spacing decreased from $12.63\;\AA$ at room temperature to $10.19\;\AA$ at $650^{\circ}C$ in the heating tests. As the pH of hectorite slurry increased. the $d_{001}$ basal spacing decreased. reaching the lowest value of $13.33\;\AA$ at pH 7 and afterward, increased. All the fool basal spacings of the hectorite increased when it was intercalated with the following solvents: $12.86\;\AA$ in diethyl ether, $13.31\;\AA$ in acetonitrile. $13.59\;\AA$ in methanol, $14.05\;\AA$ in ethanol, $15.69\;\AA$ in acetone, and $17.42\;\AA$ in ethylene glycol. Our IR analysis results were in good agreement with those of other researchers. The CEC, MB, swelling volume and specific surface area of hectorite were determined to be 105 cmol/kg, 80 cmol/kg, $68\sim74ml/2g$ and $213m^{2}/g$, respectively. Also, the hectorite to distilled water ratio of 2 to 100 was found to be most favorable for mixing with other materials such as the solvents mentioned above.

• The Journal of the Petrological Society of Korea
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• v.11 no.3_4
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• pp.200-213
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• 2002

The Andong granitoid batholith represents five temporally distinct episodes (phases) of igneous activity. The batholith represents a plutonic complex of five pulsatively emplaced distinct intrusive multiphases. The petrochemical data show that the plutons fall into calc-alkaline series except for the Yean pluton, and plot within the diaenostic range for I-type origin and continental arc orogenic tectonic setting. Each pluton reveals systematic compositional variations of major and trace elements with $SiO_2$ or MgO, but different variation trends for some elements and considerably different REE patterns. Thus discontinuous, inconsistent variations in the elements indicate that the five plutons can not be explained by simple fractional crystallization from the same primary magma, but were intruded and solidified from the independent magmas of chemically heterogeneous origin. In the Andong, Dosan and Pungsan plutons, high values of molar CaO/(MgO+$FeO^{t}$ ) combined with low $Al_2$$O_3$/(MgO+$FeO^{t}$ ) and $K_2$O$Na_2$O ratios suggest a magma originated by dehydration melting of a metabasaltic to metatonalitic protolith. Whereas the Imha pluton show similar values of CaO/(MgO+$FeO^{t}$ ), but significantly higher ratios of $Al_2$$O_3$/(MgO+$FeO^{t}$ ) and $K_2$O$Na_2$O implying to a metagreywacke protolith.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.405-414
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• 2001

Jecheon granite can be divided into two types; porphyritic granite (K-feldspar megacryst bearing) and medium-grained biotite granite. Porphyritic granite, host body of feldspar deposits, is 8${\sim}$11 km in diameter and about 80 $km^{2}$ in area. It mainly contains K-feldspar, plagioclase, biotite and quartz, and magnetite, zircon, sphene and apatite are accessary minerals. Enclosed minerals in K-feldspar megacryst with 3${\sim}$10 cm in diameter are hornblende, plagioclase, quartz, magnetite, apatite, sphene and zircon. Mafic enclaves mainly consisting of hornblende, plagioclase and quartz are frequently observed in porphrytic granite. Medium-grained biotite granite consists of K-feldspar, plagioclase, biotite and hornblende as main, and hematite, muscovite, apatite and zircon as accessary minerals. Core and rim An contents of plagioclase from porphyritic granite, medium biotite granite, K-feldspar megacryst, and mafic enclave are 36 and 21, 40 and 32, 37 and 32, and 43 and 36, respectively. $X_{Fe}$ values of hornblende are 0.57 at biotite granite, 0.51 at K-feldspar mehacryst and 0.45 at mafic enclave. $X_{Fe}$ values of biotite and hornblende are homogeneous without chemical zonation. K-feldspar megacryst shows end member of pure composition with exsolved thin lamellar pure albites. Characteristics of mineral compositions and petrography indicate porphyritic granite is igneous origin and medium-grained biotite granite comes from the same source of magma; biotite granite is initiated to solidly and from residual melt porphyritic granite can be formed. Possibly K-feldspar megacrysts are formde under H$_{2}$O undersaturation condition and near K-feldspar solidus curve temperature; growth rate is faster than nucleation rate. Mafic enclaves are thought to be mingled mafic magma in felsic magma, which is formed from compositional stratigraphy. Estimated equilibrium temperature and pressure for medium-grained biotite granite are about $800^{\circ}C$ and 4.83${\sim}$5.27 Kb, respectively.

• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.304-310
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• 2010

The FTS(Fischer-Tropsch synthesis) was carried out over precipitated iron-based catalysts with or without $SiO_2$ in a fixed-bed reactor at $250^{\circ}C$ and 1.5 MPa. The catalysts with $SiO_2$ showed much higher catalytic activity for the FTS than those without $SiO_2$, displaying excellent stability during 144 h of reaction. The X-ray diffraction and $N_2$ physisorption revealed that the catalysts with $SiO_2$ showed enhanced dispersion of $Fe_2O_3$ compared with those without $SiO_2$. Also, the results of temperature-programmed reduction by $H_2$ showed that the addition of $SiO_2$ markedly promoted the reduction of $Fe_2O_3$ into $Fe_3O_4$ and FeO at low temperatures below $260^{\circ}C$. In contrast, surface basicity of the catalysts, which was analyzed by temperature-programmed desorption of $CO_2$, decreased as a result of $SiO_2$ addition. We attribute the high and stable performance of the catalysts with $SiO_2$ to the improved dispersion and reducibility by the $SiO_2$ addition.