• Title/Summary/Keyword: LS-1

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Two new triterpenoid saponins derived from the leaves of Panax ginseng and their antiinflammatory activity

  • Li, Fu;Cao, Yufeng;Luo, Yanyan;Liu, Tingwu;Yan, Guilong;Chen, Liang;Ji, Lilian;Wang, Lun;Chen, Bin;Yaseen, Aftab;Khan, Ashfaq A.;Zhang, Guolin;Jiang, Yunyao;Liu, Jianxun;Wang, Gongcheng;Wang, Ming-Kui;Hu, Weicheng
    • Journal of Ginseng Research
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    • v.43 no.4
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    • pp.600-605
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    • 2019
  • Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositions of the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years, the aerial parts of members of the Panax genus have received great attention from natural product chemists as producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation of novel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, and their structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry, as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated on lipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside $LS_1$ (1) and 5,6-didehydroginsenoside $Rg_3$ (2), were isolated from the leaves of P. ginseng. The isolated compounds 1 and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7 cells, and Compound 2 showed a significant inhibitory effect with $IC_{50}$ of $37.38{\mu}M$ compared with that of NG-monomethyl-L-arginine ($IC_{50}=90.76{\mu}M$). Moreover, Compound 2 significantly decreased secretion of cytokines such as prostaglandin $E_2$ and tumor necrosis factor-${\alpha}$. In addition, Compound 2 significantly suppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These results suggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food, and the mechanism is warranted for further exploration.

Antioxidant and Antibacterial Activities of Glycyrrhiza uralensis Fisher (Jecheon, Korea) Extracts Obtained by various Extract Conditions (한국 제천 감초(Glycyrrhiza uralensis Fisher)의 추출 조건별 추출물의 항산화 및 항균 활성 평가)

  • Ha, Ji Hoon;Jeong, Yoon Ju;Seong, Joon Seob;Kim, Kyoung Mi;Kim, A Young;Fu, Min Min;Suh, Ji Young;Lee, Nan Hee;Park, Jino;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.41 no.4
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    • pp.361-373
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    • 2015
  • This study was carried out to evaluate the antioxidant and antibacterial activities of Glycyrriza uralensis Fisher (Jecheon, Korea) extracts obtained by various extraction conditions (85% ethanol, heating temperatures and times), and to establish the optimal extraction condition of G. uralensis for the application as cosmetic ingredients. The extracts obtained under different conditions were concentrated and made in the powdered (sample-1) and were the crude extract solutions without concentration (sample-2). The antioxidant effects were determined by free radical scavenging activity ($FSC_{50}$), ROS scavenging activity ($OSC_{50}$), and cellular protective effects. Antibacterial activity was determined by minimum inhibitory concentration (MIC) on human skin flora. DPPH free radical scavenging activity of sample-1 ($100{\mu}g/mL$) was 10% higher in group extracted for 6 h than 12 h, but sample-2 didn't show any significant differences. The extraction yield extracted with same temperature for 12 h was 2.6 times higher than 6 h, but total flavonoid content was 1.1 times higher. These results indicated that total flavonoid content hardly increased with increasing extraction time. Free radical scavenging activity, ROS scavenging activity and cellular protective effects were not dependent on the yield of extraction, but total flavonoid content of extraction. Antibacterial activity on three skin flora (S. aureus, B. subtilis, P. acnes)of sample-1 in different extraction conditions were evaluated on same concentration, and the group extracted at 25 and $40^{\circ}C$ showed 16 times higher than methyl paraben ($2,500{\mu}g/mL$). In conclusion, 85% ethanol extracts of G. uralensis extracted at $40^{\circ}C$ for 6 h showed the highest antioxidant and antibacterial activity. These results indicate that the extraction condition is important to be optimized by comprehensive evaluation of extraction yield with various conditions, yield of active component, and activity test with concentrations, and activity of 100% extract, for manufacturing process of products.

History of Biology Education in Korea During the Periord of 1880-1945 (1880-1945 년간의 한국 생물교육의 역사)

  • 김훈수
    • Animal Systematics, Evolution and Diversity
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    • v.10 no.1
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    • pp.97-123
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    • 1994
  • The author devided th period of 1876-1945 into three epochs ; the Opening of Ports in 1876 -before the Political Reform in 1894 , the Political Reform- the Japanese annexation of Korea in 1910 , and the Epoch of Japanese Colony during 1910-1945. As civilization through including educational reform rised. The modern school system began to be introduced nongovernmentally and governmentally to Korea in the 1880's without any school laws. Were chronologycally established school regulation by Korea Government in 1895-1893, school laws by Korean Government under the supervision of the Japanese Residency-General of Korea in 1906-1910, and the educational laws of Korea by the Japanese Government-General of Korea in 1911-1943. In these epochs, the numbers of elementary , secondary and higher educational institutions and the numbers of pupils and students had increased slowly. Japanese had developed sonwhat primary education and secondary technical education, but it had checked extremely the Korean peoples to receive secondary liberal education and higher education, On the epoch of Japanese colony, Japanese occupied nearly half of elementary school teachers, almost of public secondary school teachers educated in Japan, and nearly all of professor educated in Japan in public and national colleges which were technical, and in one imperial university . Forty or more Korean teachers taught natural history chief at private secondary schools for Koreans , more than half of them being graduates of colleges of agriculture and forestry in Korea and Japan. The author mentioned curricula , and subjects and textbooks connected with biology of elementary, secondary and higher educational institutions. The pup8ls and students received biological knowledge through learning sciences at primary schools ; natural history (plants, animals and minerals ) at secondary schools including normal schools ; botany, zoology, genetics and major subjects related with biology such as anatomy, physiology, bacteriology, pland breeding at medical colleges and colleges of agriculture and forestry. There were no departments of biology , botany or zoology in Korea. Only seven Koreas graduated from departments of biology, botany or zoology at imperial universities in Japan. Some of them played the leading parts to develop education and researches of biology in the universities after 1945 Liberation.

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Effects of Pine Needle Extract Oil on Blood Glucose and Serum Insulin Levels in db/db Mice (2형 당뇨 마우스에서 솔잎 추출용액의 경구투여가 혈당조절에 미치는 영향)

  • Kim, Mi-Joung;Ahn, Jin-Hong;Choi, Kang-Ho;Lee, Yun-Hak;Woo, Gyeong-Jin;Hong, Eun-Kyung;Chung, Young-Shin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.3
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    • pp.321-327
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    • 2006
  • This study was performed to investigate the hypoglycemic effect of pine needle extract oil against type 2 diabetes. Six-week-old male C57BL/Ks(db/db) mice were divided into four groups : negative control, pine needle extract oil low dose, high dose and positive control groups, which fed daily for 6 weeks with corn oil, pine needle extract oil 112.5 mg/kg, 450 mg/kg or metformin (150 mg/kg ), respectively. The oral administration of the pine needle extract oil resulted in the significant and dose-dependent decreases of blood glucose levels in comparison with corn oil treatment. The levels of HbAlc showed a tendency of the decrease by the high dose treatment of the pine needle extract oil and were positively correlated with blood glucose levels (r=0.5046, p=0.0023) . However, the levels of serum insulin and C-peptide were not affected by pine needle extract oil or metformin treatments. The levels of serum leptin, which is related with the insulin sensitivity, showed a tendency of the increases by pine needle extract oil treatment and were negatively correlated to blood glucose levels (r=-0.4754, p=0.0052). In conclusion, these results suggest that the pine needle extract oil have a potential for the oral anti-hyperglycemic agent and the mode of action may be related with the improvement of the insulin sensitivity through blood leptin.

Antimicrobial, Antioxidant and Cellular Protective Effects against Oxidative Stress of Anemarrhena asphodeloides Bunge Extract and Fraction (지모 뿌리 추출물과 분획물의 항균활성과 항산화 활성 및 세포보호 연구)

  • Lee, Yun Ju;Song, Ba Reum;Lee, Sang Lae;Shin, Hyuk Soo;Park, Soo Nam
    • Microbiology and Biotechnology Letters
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    • v.46 no.4
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    • pp.360-371
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    • 2018
  • Extracts and fractions of Anemarrhena asphodeloides Bunge were prepared and their physiological activities and components were analyzed. Antimicrobial activities of the ethyl acetate and aglycone fractions were $78{\mu}g/ml$ and $31{\mu}g/ml$, respectively, for Staphylococcus aureus and $156{\mu}g/ml$ and $125{\mu}g/ml$, respectively, for Pseudomonas aeruginosa. 1,1-Diphenyl-2-picrylhydrazyl free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction, and aglycone fraction of A. asphodeloides extracts were $146.2{\mu}g/ml$, $23.19{\mu}g/ml$, and $71.06{\mu}g/ml$, respectively. The total antioxidant capacity ($OSC_{50}$) in an $Fe^{3+}$-EDTA/hydrogen peroxide ($H_2O_2$) system were $17.5{\mu}g/ml$, $1.5{\mu}g/ml$, and $1.4{\mu}g/ml$, respectively. The cytoprotective effect (${\tau}_{50}$) in $^1O_2$-induced erythrocyte hemolysis was 181 min with $4{\mu}g/ml$ of the aglycone fraction. The ${\tau}_{50}$ of the aglycone fraction was approximately 4-times higher than that of (+)-${\alpha}$-tocopherol (${\tau}_{50}$, 41 min). Analysis of $H_2O_2$-induced damage of HaCaT cells revealed that the maximum cell viabilities for the 50% ethanol extract, ethyl acetate fraction, and aglycone fraction were 86.23%, 86.59%, and 89.70%, respectively. The aglycone fraction increased cell viability up to 11.53% at $1{\mu}g/ml$ compared to the positive control treated with $H_2O_2$. Analysis of ultraviolet B radiation-induced HaCaT cell damage revealed up to 41.77% decreased intracellular reactive oxygen species in the $2{\mu}g/ml$ aglycone fraction compared with the positive control treated with ultraviolet B radiation. The findings suggest that the extracts and fractions of A. asphodeloides Bunge have potential applications in the field of cosmetics as natural preservatives and antioxidants.

A study on educational need of nurses for home care (간호사의 가정간호를 위한 교육요구 분석)

  • Moon Jung-Soon
    • Journal of Korean Public Health Nursing
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    • v.5 no.2
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    • pp.5-25
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    • 1991
  • This study was conducted from July to December 1990, in order to diagnose nurses' educational need for home care. The study subjects consisted of 145 nursing educators, and the 3 groups of nurses, namely 250 senior nursing students of diploma and collegiate program, 235 health center nurses, 521 university' hospital nurses in Seoul. Four types of questionaires were formulated by Delphi method. Two questionaires for the nursing educators were designed to measure their expectations of nurses' knowledge and of their skill for home care, and another two questionaires for the nurses to measure their actual home care knowledge and skill. The results of the study were as follows : 1) The mean scores of educators' expectation for home care knowledge were 17.68 for the care of dependence on medical equipment, 17.44 for the care of mobility impairment patient, 16.56 for the care of cardiopulmonary impairment patient, 16.40 for the care of nutrition and elimination impairment patient, '1.20 for the care of psychiatric disorder patient and 9.03 for the care of cancer and terminally ill patient,. 2) The mean scores of nurses' home care knowledge tested by 20 items were 14.36 for the care of mobility impairment patient, 13.28 for the c8;re of dependence on medical equipment, 13.78 for the care of cardiopulmonary impairment patient, 12.92 for the care of nutrition and elimination impairment patient, and those of tested by 10 items were 7.08 for the care of psychologic disorder patient, 7.80 for the care of cancer and terminally ill patient. The sum of means marked 69.23. As for the nurses' home care knowledge categorized by tasks in terms of the group, significant difference were shown in the care of mobility impairment(P=0.00), cancer and terminally ill(P=0.03), nutrition and elimination impairment(P=0.00) and psychologic disorder patient(P=0.00). No significant difference were shown in the care of dependence on medical equipment and cardiopulmonary impairment patient. 3) Regard to educational need of nurses' home care knowledge categorized by task according to the group it was found that all sampled nurses had educational need in the care of mobility impairment, dependence on medical equipment, cardiopulmonary impairment, cancer and terminally ill patient. It was found that health center nurses had educational need in the care of psychologic disorder. No educational need were found in the health center nurses whose career less than 2 years, in the care of mobility impairment, cardiopulmonary impairment and psychologic disorder patient, and in those of career with 2-5 year in the care of psychologic disorder patient. No educational need were found in the hospital nurses whose career more than 15 years, in the care of cardiopulmonary impairment patient and in those of career with 11-15 year, in the care of cancer and terminally ill patient. 4) The mean scores of educators' expectation for home care skill measured by Likert 5 points scale were 4. 21 for assessing, 4.49 for planning, 4.29 for basic care, 4.42 for curative care, 4.40 for rehabilitative care, 4.36 for emergency care, 4.53 for medication, 4.31 for nutritional care, 4.32 for other means for care, and 4.38 for evaluation. 5) Regard to nurses' home care skill measured by Likert 5 points scale of self evaluation, there was a significant difference between the nurses' home care skill and group(P=0.00l). The higher scores reported by students were vital sign checking and basic care while the scores of below medium were curative care and emergency care. The higher scores reported by health center nurses were vital sign checking, other means for care and care of specimen while the scores below medium were curative, emergency and nutritional care. The higher scores reported by hospital nurses were vital sign checking, care of specimen and basic care, while the score below medium was emergency care. 6) Regard to educational need of nurses' home care skill by nursing process activity according to the group it was found that health center nurses had educational need in all nursing skills including vital sign checking, care of specimen, health assessment, socioeconomic assessment, nursing diagnosis, care plan, basic care, curative care, rehabiitative care, psychological care, emergency care, medication, nutritional care, other means for care and evaluation. And students had educational need in all nursing skills except vital sign checking, and hospital nurses had educational need in all nursing skills except vital sign checking, care of specimen and basic care. 7) In short, the result of this study suggests that the curriculum should be organized in accordence with nurses' educational background and their career for the education of nurses for home care. It should be considered to develop the short term educational program focused on curative and rehabilitative care for health center nurse or community health nurse practitioner and which was focused on family care for hospital nurse. Concerning about this field practice for home care nurse, they are required not only community practice but also . clinical practice including emergency, curative and rehabilitative care.

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Prediction of Soil Erosion from Agricultural Uplands under Precipitation Change Scenarios (우리나라 강우량 변화 시나리오에 따른 밭토양의 토양 유실량 변화 예측)

  • Kim, Min-Kyeong;Hur, Seong-Oh;Kwon, Soon-Ik;Jung, Goo-Bok;Sonn, Yeon-Kyu;Ha, Sang-Keun;Lee, Deog-Bae
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.6
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    • pp.789-792
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    • 2010
  • Major impacts of climate change expert that soil erosion rate may increase during the $21^{st}$ century. This study was conducted to assess the potential impacts of climate change on soil erosion by water in Korea. The soil loss was estimated for regions with the potential risk of soil erosion on a national scale. For computation, Universal Soil Loss Equation (USLE) with rainfall and runoff erosivity factors (R), cover management factors (C), support practice factors (P) and revised USLE with soil erodibility factors (K) and topographic factors (LS) were used. RUSLE, the revised version of USLE, was modified for Korean conditions and re-evaluate to estimate the national-scale of soil loss based on the digital soil maps for Korea. The change of precipitation for 2010 to 2090s were predicted under A1B scenarios made by National Institute of Meteorological Research in Korea. Future soil loss was predicted based on a change of R factor. As results, the predicted precipitations were increased by 6.7% for 2010 to 2030s, 9.5% for 2040 to 2060s and 190% for 2070 to 2090s, respectively. The total soil loss from uplands in 2005 was estimated approximately $28{\times}10^6$ ton. Total soil losses were estimated as $31{\times}10^6$ ton in 2010 to 2030s, $31{\times}10^6$ ton in 2040 to 2060s and $33{\times}10^6$ ton in 2070 to 2090s, respectively. As precipitation increased by 17% in the end of $21^{st}$ century, the total soil loss was increased by 12.9%. Overall, these results emphasize the significance of precipitation. However, it should be noted that when precipitation becomes insignificant, the results may turn out to be complex due to the large interaction among plant biomass, runoff and erosion. This may cause increase or decrease the overall erosion.

An Analysis of the Landscape Cognitive Characteristics of 'Gugok Streams' in the First Half of the 18th Century Based on the Comparison of China's 『Wuyi-Gugok Painting』 (중국 『무이구곡도』 3폭(幅)의 비교 분석을 통해 본 18세기 무이산 구곡계(九曲溪)의 경물 인지특성)

  • Cheng, Zhao-Xia;Rho, Jae-Hyun;Jiang, Cheng
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.37 no.3
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    • pp.62-82
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    • 2019
  • Taking the three Wuyi-Gugok Drawings, 『A Picture Showing the Boundary Between Mountains and Rivers: A』, 『Landscape of the Jiuqu River in the Wuyi Mountain: B』 and 『Eighteen Sceneries of Wuyi Mountain: C』, which were produced in the mid-Qing Dynasty as the research objects and after investigating the names recorded in the paintings, this paper tries to analyze the scenic spots, scene types and images in the literature survey. Also, based on the number of Scenic type and the number of Scenic name in each Gok, landscape richness(LR) and landscape similarity(LS) of the Gugok scenic spots, the cognitive characteristics of the landscape in the 18th century were carefully observed. The results are as follows. Firstly, according to the description statistics of scenic spot types in Wuyi Mountain Chronicle, there were 41 descriptions of scenery names in the three paintings, among which rock, peak and stone accounted for the majority. According to the data, the number of rocks, peaks and stones in Wuyi-Gugok landscape accounted for more than half, which reflected the characteristics of geological landscape such as Danxia landform in Wuyi-Gugok landscape. Secondly, the landscape of Gugok Stream(九曲溪) was diverse and full of images. The 1st Gok Daewangbong(大王峰) and Manjeongbong(幔亭峰), the 2nd Gok Oknyeobong(玉女峰), the 3rd Gok Sojangbong(小藏峰), the 4th Gok Daejangbong(大藏峰), the 5th Gok Daeeunbyeong(大隱屛) and Muijeongsa(武夷精舍), the 6th Gok Seonjangbong(仙掌峰) and Cheonyubong(天游峰) all had outstanding landscape in each Gok. However, the landscape features of the 7th~9th Gok were relatively low. Thirdly, according to the landscape image survey of each Gok, the image formation of Gugok cultural landscape originates from the specificity of the myths and legends related to Wuyi Mountain, and the landscape is highly well-known. Due to the specificity, the landscape recognition was very high. In particular, the 1st Gok and the 5th Gok closely related to the Taoist culture based on Muigun, the Stone Carving culture and the Boat Tour culture related to neo-confucianism culture of Zhu Xi. Fourthly, according to the analysis results of landscape similarity of 41 landscape types shown in the figure, the similarity of A and C was very high. The morphological description and the relationship of distant and near performance was very similar. Therefore, it could be judged that this was obviously influenced by one painting. As a whole, the names of the scenes depicted in the three paintings were formed at least in the first half of 18th century through a long history of inheritance, accumulated myths and legends, and the names of the scenes. The order of the scenery names in three Drawings had some differences. But among the scenery names appearing in all three Drawings, there were 21 stones, 20 rocks and 17 peaks. Stones, rocks and peaks guided the landscape of Gugok Streams in Wuyi Mountain. Fifthly, Seonjodae(仙釣臺) in A and C was described in the 4th Gok, but what deserved attention was that it was known as the scenery name of the 3rd Gok in Korean. In addition, Seungjindong(升眞洞) in the 1st Gok and Seokdangsa(石堂寺) in the 7th Gok were not described in Drawings A, B and C. This is a special point that needs to be studied in the future.

Recent Progress in Air-Conditioning and Refrigeration Research : A Review of Papers Published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2016 (설비공학 분야의 최근 연구 동향 : 2016년 학회지 논문에 대한 종합적 고찰)

  • Lee, Dae-Young;Kim, Sa Ryang;Kim, Hyun-Jung;Kim, Dong-Seon;Park, Jun-Seok;Ihm, Pyeong Chan
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.29 no.6
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    • pp.327-340
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    • 2017
  • This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

Evaluation of Lead, Copper, Cadmium, and Mercury Species in the Leachate of Steel Making Slag by Seawater (해수에 의한 제강 슬래그의 납, 구리, 카드뮴 및 수은 화합물의 용출특성 평가)

  • Lee, Han-Kook;Lee, Dong-Hoon
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.75-84
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    • 2005
  • The aim of this study is to evaluate the leaching characteristics of lead, copper, cadmium, and mercury from steel making slag by seawater. To demonstrate the leaching characteristics of heavy metals from steel making slag by seawater, it was carried to various leaching tests such as regular leaching tests, liquid/sold(LS) leaching test and pH static test. From the leachability of $Pb^{+2},\;Cu^{+2},\;and\;Cd^{+2}$ from steel making slag in pH static test, it is distinguished between distilled water and seawater. With distilled water, it is very low between pH 7-8 and pH 11-12. On the other hands, with the seawater, its leaching is higher than that of distilled water. In particular, concentration of $Hg^{+2}$ leached from slag by seawater is lower than that of distilled water. Meanwhile, we found that the heavy metals from steel making slag would be dissolved and precipitated using geochemcial equilibrium program such as visual minteq. Lead and copper leached from steel making slag with seawater were dissolved nearly in the range of pH 11-12, but in the range of pH 7-10 those were precipitated about 90%. And cadmium leached from steel making slag with seawater were dissolved completely. On pH static test with distilled water, lead leached from steel making slag seemed to be similar to pH static test with seawater. However, copper and cadmium leached from steel making slag were dissolved. In general, the species of lead leached from steel making slag were formed mainly of $PbCl^+,\;PbSO_4$, the species of copper were formed mainly of $CuSO_4,\;CuCO_3$, the species of cadmium were formed mainly of $CdCl^+,\;CdSO_4$ due to being sorbed with the anions($Cl^-,\;CO_3^{-2},\;SO_4^{-2}$) of the seawater. Both pH static test with seawater and distilled water, it is not in the case of the mercury. Most of mercury leached from steel making slag was precipitated(SI=0). Because the decreasing of $Hg^{+2}$ concentrations depends ferociously on the variation of chloride($Cl^-$) existed in the seawater. $Hg^{+2}$ leached from steel making slag could be sorbed strongly with chloride($Cl^-$) compared of carbonate($CO_3^{-2}$) and sulfate($SO_4^{-2}$) in the seawater. On the basis of that result, we found that the species of mercury was formed of calomel($Hg_2Cl_2$) as one of finite solid. Due to forming a calomel($Hg_2Cl_2$) in the seawater, the stability of mercury species by steel making slag should be higher than those of lead, copper, and cadmium species. Regarding the results stated above, we postulated that the steel making slag could be recycled to sea aggregates due to being distinguishing leachability of heavy metals($Pb^{+2},\;Cu^{+2},\;Cd^{+2},\;and\;Hg^{+2}$) between leaching tests by distilled water and seawater.