• 한국압력기기공학회 논문집
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• 제12권1호
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• pp.101-106
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• 2016

NSSS (Nuclear Steam Supply System) and BOP (Balance of Plant) design works for PGSFR (Prototype Gen-IV Sodium Fast Reactor) have been conducted in Korea. NSSS major components, e.g. reactor vessel, steam generator and secondary sodium main pipes, are designed according to the rule of ASME boiler and pressure vessel code division 5, in which DBA (Design by Analysis) methods are used in the stress assessments. However, there is little discussions about detail rules for BOP piping design. In this paper, the detail methodologies of BOP piping stress assessment are discussed including safety systems and non-safety system pipings. It is confirmed that KEPIC MGE(ASME B31.1) and ASME BPV code division 5 HCB-3600 can be used in stress assessments of non-safety pipes and class B pipes, respectively. However, class A pipe design according to ASME BPV code division 5 HBB-3200 has many difficulties applying to PGSFR BOP design. Finally, future development plan for class A pipe stress assessment method is proposed in this paper.

• 상하수도학회지
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• 제33권3호
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• pp.205-213
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• 2019

Batch adsorption tests were performed to evaluate the applicability of adsorption kinetic model by using hydrogel chitosan bead crosslinked with glutaraldehyde (HCB-G) for Cu(II) as cation and/or phosphate as anion. Pseudo first and second order model were applied to determine the sorption kinetic property and intraparticle and Boyd equation were used to predict the diffusion of Cu(II) and phosphate at pore and boundary-layer, respectively. According to the value of theoretical and experimental uptake of Cu(II) and phosphate, pseudo second order is more suitable. On comparison with the value of adsorption rate constant (k), phosphate kinetic was 2-4 times faster than that of Cu(II) at any experimental condition indicating the electrostatic interaction between ${NH_3}^+$ and phosphate is dominated at the presence of single component. However, when Cu(II) and phosphate simultaneously exist, the value of k for phosphate was sharply decreased and then the difference was not significant. Both diffusion models confirmed that the sorption rate was controlled by film mass transfer at the beginning time (t < 3 hr) and pore diffusion at next time section (t > 6 hr).

• 한국환경보건학회지
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• 제36권2호
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• pp.118-127
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• 2010

Bivalve samples from 30 locations Korean coastal waters were analyzed to characterize the contamination with and distribution of polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). The congeners of PBDE in 30 bivalve samples were analyzed by high resolution gas chromatography with a high resolution mass detector. The levels of PBDEs in bivalve samples ranged from 0.092 to 13.5 ng/g wet weight. These values for PBDEs concentrations in bivalves from Korea were higher than or comparable to available values for bivalves from other countries. In the congener profiles, BDE-47 (mean contribution=42.2%) was predominant, followed by BDE-99 (23.1%), BDE-100 (11.9%) and BDE-154 (3.5%). Among the OCs analyzed, $\Sigma$PCBs and $\Sigma$DDTs levels were highest, followed by $\Sigma$HCHs, $\Sigma$CHLs and HCB. The wet weight based $\Sigma$PCBs and $\Sigma$DDTs ranged from 0.28 ng/g to 19.4 ng/g, and from 0.19 ng/g to 4.86 ng/g, respectively. The $\Sigma$PCBs and $\Sigma$DDT slevels in bivalves along the entire Korean coast were lower than those of the USA, and below the Food and Drug Administration (USA. FDA) limits for fish and shell fish. However, the human health criteria and wild life criteria of the USA. Environmental Protection Agency (USA. EPA) were exceeded for DDE and $\Sigma$HCHs at most of the sampling points.

• 한방안이비인후피부과학회지
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• 제18권1호
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• pp.61-70
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• 2005

Objective : This study was performed to investigate the effects of OWT on allergic bronchial asthma. Methods : The mice were divided into 4 groups induced the allergic bronchial asthma : Three groups(OWT-1, OWT-2, OWT-3) treated OWT and non-treated group(Control). Three oral administration of the herbal solution of OWT were carried out 1 lime a day for 2 weeks before antigen sensitization. 2 days later, the mice were sensitized with a subcutaneous injection of ovalbumin(OA) and then 13 days later they were provoked with OA aerosols. Then the cell numbers in bronchoalveolar lavage fluid(BALF), serum level of IgE, WBC, RBC and HCB were measured. Results : 1. On the neutrophil in BALF, OWT-1 group is significantly increased compared with the control group. 2. On the eosinophil in BALF, OWT-1 group tends to decrease compared with the control group but insignificant. 3. On the lymphocyte in BALF, OWT-2 group is significantly decreased compared with the control group. 4. On the macrophage in BALF, OWT-2 group is significantly increased compared with the control group. 5. On the serum IgE, groups OWT-1, OWT-2 and OWT-3 are significantly decreased compared with the control group. 6. On WBC in blood, OWT-1 group is significantly decreased compared with the control group. Conclusions : Based on the above results, it is assumed that the oral administration of OWT can help the treatment of allergic bronchial asthma.

• Molecules and Cells
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• 제39권10호
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• pp.728-733
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• 2016

Mesenchymal stem cells (MSCs) effectively reduce airway inflammation and regenerate the alveolus in cigarette- and elastase-induced chronic obstructive pulmonary disease (COPD) animal models. The effects of stem cells are thought to be paracrine and immune-modulatory because very few stem cells remain in the lung one day after their systemic injection, which has been demonstrated previously. In this report, we analyzed the gene expression profiles to compare mouse lungs with chronic exposure to cigarette smoke with non-exposed lungs. Gene expression profiling was also conducted in a mouse lung tissue with chronic exposure to cigarette smoke following the systemic injection of human cord blood-derived mesenchymal stem cells (hCB-MSCs). Globally, 834 genes were differentially expressed after systemic injection of hCB-MSCs. Seven and 21 genes, respectively, were up-and downregulated on days 1, 4, and 14 after HCB-MSC injection. The Hbb and Hba, genes with oxygen transport and antioxidant functions, were increased on days 1 and 14. A serine protease inhibitor was also increased at a similar time point after injection of hCB-MSCs. Gene Ontology analysis indicated that the levels of genes related to immune responses, metabolic processes, and blood vessel development were altered, indicating host responses after hCB-MSC injection. These gene expression changes suggest that MSCs induce a regeneration mechanism against COPD induced by cigarette smoke. These analyses provide basic data for understanding the regeneration mechanisms promoted by hCB-MSCs in cigarette smoke-induced COPD.

• Computers and Concrete
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• 제10권1호
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• pp.1-18
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• 2012

This paper presents the details of studies conducted on hollow concrete block masonry (HCBM) units and wall panels. This study includes, compressive strength of unit block, ungrouted and grouted HCB prisms, flexural strength evaluation, testing of HCBM panels with and without opening. Non-linear finite element (FE) analysis of HCBM panels with and without opening has been carried out by simulating the actual test conditions. Constant vertical load is applied on the top of the wall panel and then lateral load is applied in incremental manner. The in-plane deformation is recorded under each incremental lateral load. Displacement ductility factors and response reduction factors have been evaluated based on experimental results. From the study, it is observed that fully grouted and partially reinforced HCBM panel without opening performed well compared to other types of wall panels in lateral load resistance and displacement ductility. In all the wall panels, shear cracks originated at loading point and moved towards the compression toe of the wall. The force reduction factor of a wall panel with opening is much less when compared with fully reinforced wall panel with no opening. The displacement values obtained by non-linear FE analysis are found to be in good agreement with the corresponding experimental values. The influence of mortar joint has been included in the stress-strain behaviour as a monolith with HCBM and not considered separately. The derived response reduction factors will be useful for the design of reinforced HCBM wall panels subjected to lateral forces generated due to earthquakes.

• 한국식품저장유통학회지
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• 제16권1호
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• pp.122-127
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• 2009

어성초가 자연발효에 의존할 경우 잡균 및 산막효모의 오염 및 발효기간이 오래 걸린다는 단점이 있다. 본 연구는 전통적인 방법으로 발효된 어성초 엑기스에서 야생효모를 분리하고, 어성초 추출물에서의 발효 특성을 검토하였다. 그 결과, $15^{\circ}Brix$ 당용액에서 알코올 함량은 배양시간이 길어질수록 증가하여 배양 90시간째에 HCE 12%, HCD 11.2%, HCA 10.5% 순으로 높았다. HCF, HCG, HCB, HCC는 알코올 함량이 $7.5{\sim}8.5%$ 사이였다. 당용액에서 알코올 생성능이 가장 높은 HCE와 HCD 균주를 어성초 분리효모로 선정하고, 어성초배지(어성초 착즙액:증류수(1:1)에서 기존 Saccharomyces 균주와 발효력 비교 검토 결과, pH는 발효 전 $4.09{\sim}4.12$에서 발효 후 $3.57{\sim}3.78$로, 당도는 발효전 $15.00{\sim}15.19$에서 $7.75{\sim}9.57$로 감소하였다. 산도는 발효전 $0.138{\sim}0.210$에서 발효 후 $0.282{\sim}0.450$으로 증가하였으며, 알코올 함량은 발효 후 $3.6{\sim}4.6$으로 어성초 분리균인 HCD와 HCE가 감, 사과 및 포도에서 분리한 DJ97, YJK, R12, RCY 보다 소폭 높았다. 발효된 어성초배양액은 어성초 특유의 강한 비린내가 감소하고 생성된 알코올로 인해향은 보통 수준 이상의 관능평가를 얻었으나, 맛은 보통 이하로 낮은 관능평가를 얻었다. 색은 최저 $4.75{\pm}1.44$, 최고 $6.85{\pm}1.63$으로 HCE가 관능항목 중 가장 높은 점수를 얻었다. 전반적인 기호도는 최저 $3.95{\pm}1.17$, 최고 $5.00{\pm}1.41$로 보통의 수준으로 이는 맛의 기호도가 충족되지 못하여 낮은 관능평가를 얻은 것으로 사료된다. 그러나, 색, 향, 맛, 전반적인 기호도에서 균주간의 유의성(p<0.05)은 인정되지 않았다. 어성초 특유의 비린내를 보완할 수 있는 부재료를 첨가하여 맛을 완화시킬 수 있다면 어성초를 이용한 약용주의 개발도 가능할 것으로 판단된다.

• 환경위생공학
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• 제22권2호
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• pp.9-20
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• 2007

The incineration process has commonly used for wastes amount reduction and thermal treatments of pollutants as the technologies accumulated. However, the process is getting negative public images owing to matter of hazardous pollutants emission. Specially dioxins became a main issue and were mostly emitted from municipal solid wastes incineration. In this reason, pyrolysis/gasification/melting process is presented as an alternative of incineration process. The pyrolysis/gasification/melting process, a novel technology, is middle of verification of commercial plant and development of technologies in Korea. But the survey about the pollutant emission from the process, and background data in these facilities is necessary. So in this survey, t is investigated that the behavior of chlorobenzenes and chlorophenols in plasma type pyrolysis/gasification/melting plant of pilot scale. We investigated discharging behavior of each phase of chlorobenzene through each process in the plsasma type pyrolysis/gasification/melting process. From this result, it was found that about 99 percent of particle-phase chlorobenzene was removed, but on the other hand gas-phase chlorobenzene was increased by about 600 percent through heat exchanger, flue gas cooling, system and semi dry absorption bag filter(SDA/BF). Also, this investigation presented that di-chlorobenzene(DCB) tri-chlorobenzene(TCB), tetra-chlorobenzene(TeCB), penta-chlorobenzene (PCB), except mono-chlorobenzene(MCB) and hexa-chlorobenzene(HCB) were increased through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). It was investigated that concentration of particle-phase chlorophenol was decreased by about 66 percent, but on the other hand, concentration of gas-phase chlorophenol was increased by about 170 percent through heat exchanger, flue gas cooling system, and semi dry absorption bag filter(SDA/BF). Also, it was found that di-chlorophenol(DCP), tri-chlorophenol(TCP), and penta-chlorophenol(PCP) were increased through the flue gas cooling system, and the semi dry absorption bag filter(SDA/BF). It can be considered that small-scale pilot facility and short investigation period might cause the concentration increase through the flue gas cooling system and the semi dry absorption bag filter(SDA/BF). A further study on real-scale pilot facility and accurate investigation may be required.

• 분석과학
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• 제19권1호
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• pp.86-95
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• 2006

현재 가동 중인 생활폐기물 소각시설에서 배출되는 소각재의 수세처리에 의한 유기화학물질 용출특성을 확인하기 위해 GC/MSD로 정성 분석을 하였다. 바닥재 및 비산재에서 각각 44종 및 17종의 다양한 유기화합물질을 확인하였다. 이러한 정성분석은 각 피크의 질량스펙트럼에 대한 Library(NIST21, NIST107, WILEY229) 검색 후 일치도가 90% 이상인 유사지표(similarity index)에 의해 수행되었다. 바닥재는 Naphthalene 그리고 Phenanthrene인 2종의 다방향족화합물(Polycyclic Aromatic Hydrocarbons, PAHs)을 포함한 18종의 방향족화합물과 사슬모양의 탄화수소인 26종의 지방족화합물을 검출하였다. 비산재의 경우 잔류성유기오염물질(Persistent Organic Pollutants, POPs)인 헥사클로로벤젠(Hexachlorobenzene, HCB)을 포함한 10종의 방향족화합물과 7종의 지방족화합물을 정성적으로 확인하였다. 또한, 바닥재와 비산재의 용출액과 용출잔사의 용출특성을 비교분석한 결과, 바닥재에서는 Ethenylbenzene, Benzaldehyde, 1-Phenyl-ethanone 그리고 1,4-Benzenedicarboxylic acid dimethyl ester 등이, 비산재에서는 Naphthalene, Dodecane, 1,2,3,5-Tetrachlorobenzene, Tetradecane, Hexadecane 그리고 Pentachlorobenzene등의 유기화합물이 수층으로 용출되는 결과를 얻었다. 따라서 소각재 중 비산재 및 바닥재가 단순 매립될 경우 유기화합물에 의한 침출수 및 지하수, 토양 등 2차 오염이 발생할 것으로 추정되며, 이러한 2차 오염을 방지하기 위해서 소각재에 함유되어 있는 다양한 종류의 유기화학물질의 용출특성을 조사하여 이에 대한 효율적이고 적정한 관리가 이루어져야 할 것으로 판단된다.