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A Study on the Medical Accident Attack Rate in a Korean rural Area through the Sam Wha Medicare Insurance Union (충남 서산군 삼화의료보험조합을 통해본 일부 농촌지역 주민의 의료사고 발생율 및 진료수혜 실태 조사)

  • Ahn, Moon-Young;Lee, Jung-Ja;Nam, Taik-Sung
    • Journal of agricultural medicine and community health
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    • v.6 no.1
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    • pp.33-41
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    • 1981
  • To investigate the status of medical accident attack rate and medicare utilization during last 27months from 1st Oct., 1977 to 31st Dec. 1979 in the area under Sam Wha Medicare Insurance Union, the study was carried out through analyzing the medicare records of patients who were enrolled. "The medical accident" in this study was used as the meaning of the state that the people who have been treated morbid condition with insurance money. For the study, 2 doctors and one nurse were mobilized and the results are as follows: 1) The total number of the Medicare Insurance Union members among the 37,044 total population of the study area, (Hea-mi, Unsan, Eumam Myun) were 57, 35 composed of 3,000 males (52.3%) and 27, 35 females (47.7%) in 1977, 3,383 composed of 2,006 males (59.3%) 1,377 females (40.7%) in 1978, 2,573 composed of 1,437 males and 1,336 females (44.2%) in 1979. 2) Total number of medical accident attack cases were 6,774 case (partially overlapped the number of the 1977 with that of the 1978) and average annual medical accident attack rate per 1,000 population was 700.9. 3) Five major disease group in the past three years were disease of the respiratory system (177.7), disease of the digestive system (165.8), disease of the skin and subcutaneous(64.9), symptoms, signs and ill-defined conditions (64.6), any injury and poisoning (51.9). Mental disorders (32.6) was the 6th order disease group. 4) The order of the medical accident attack rate of age group per 1,000 population per year was the year group of 0~4(877.8), 45~64(832.6), 25~44(810.3), 5~14(495.1) 15~24(494.7) 65 and over (460.7). 5) Medical accident attack rate of age group per 1,000 population in the 5 major disease groups were the year group of 45~64 (100.0) in the mental disorders 0~4(525.1) in the disease of the respiratory system 45~64 (328.5) in the disease of the digestive system 0~4 (202.8) in the disease of the skin and subcutanous tissue, 25~44 (98.3) in the accidents and poisoning. 6) Monthly medical accidents attack rate were 87.0 in the winter (Dsc., Jan., Feb.) and 86.2 in the summer (Jun., July, Aug.). So the trend of the medical accidents attack rate during the year was bimount figure. 7) Monthly medical accidents attack rate in the major disease group were highest in Jan., Apr., (31.1) in the disease of the respiratory system, in Jan., Feb., Mar. (24.9) in the disease of the digestive system, in Jan., Jun., Aug. (9.8) in the injury and poisoning. 8) Duration of the treatment of the 93.1% of the total cases were within 5 days. 9) 299 cases (4.5%) of the total number of cases, 6,587 cases were referred to secondary and tertiary medicare facilities. 10) The order of the major 10 kinds of diagnosis of the disease, 6,587 cases during 27 months, were URI and chillness (1,063 cases, 16.1%), gastritis(830 cases, 12. 6%) dermatitis(360 cases, 5.5%), bronchitis(291 cases, 4.4%), neurosis (284 cases, 4.3%), contusion (165 cases, 2.5%), tooth extraction (157 cases, 2.4%), tonsillitis (109 cases, 0.7%), laceration (107 cases, 1.6%), neuralgia (105 cases, 1.6%), arthritis (104 cases, 1.6%), otitis media and mastoiditis (103 cases, 1.6%), so total case were 3,678 cases (55.9%).

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Low price type inspection and monitoring system of lithium ion batteries for hybrid vessels (하이브리드 선박용 리튬 배터리의 저가형 감시시스템 구현)

  • Kwon, Hyuk-joo;Kim, Min-kwon;Lee, Sung-geun
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.1
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    • pp.28-33
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    • 2016
  • Batteries are used for main power engine in the fields such as mobiles, electric vehicles and unmanned submarines, for starter and lamp driver in general automotive, for emergency electric source in ship. These days, lead-acid and the lithium ion batteries are increasingly used in the fields of the secondary battery, and the lead-acid battery has a low price and safety comparatively, The lithium ion battery has a high energy density, excellent output characteristics and long life, whereas it has the risk of explosion by reacting with moisture in the air. But Recently, due to the development of waterproof, fireproof, dustproof technology, lithium batteries are widely used, particularly, because their usages are getting wider enough to be used as a power source for hybrid ship and electric propulsion ship, it is necessary to manage more strictly. Hybrid ship has power supply units connected to the packets to produce more than 500kWh large power source, and therefore, A number of the communication modules and wires need to implement the wire inspection and monitor system(WIIMS) that allows monitoring server to transmit detecting voltage, current and temperature data, which is required for the management of the batteries. This paper implements a low price type wireless inspection and monitoring system(WILIMS) of the lithium ion battery for hybrid vessels using BLE wireless communication modules and power line modem( PLM), which have the advantages of low price, no electric lines compared to serial communication inspection systems(SCIS). There are state of charge(SOC), state of health(SOH) in inspection parts of batteries, and proposed system will be able to prevent safety accidents because it allows us to predict life time and make a preventive maintenance by checking them at regular intervals.

A Study on Sickness and the Status of Medical Care in a Rural Area (일부(一部) 농촌주민(農村住民)의 상병(傷病) 및 의료실태(醫療實態)에 관(關)한 조사연구(調査硏究))

  • Park, Jeong-Sun
    • Journal of Preventive Medicine and Public Health
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    • v.14 no.1
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    • pp.65-74
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    • 1981
  • This survey was made to determine the overall health situation on (1) the status of sickness; (2) the medical care utilization; (3) the medical cost in Mi-Kum Myun, Nam Yang Ju Gun, Kyung-Gi Do. The survey with questionnaire was carried out with 2,840 peoples in 560 households from August 9th to 16th, 1979. The findings from the survey were as follows; 1. Annual morbidity rate of the prolonged ill cases was 97.2 per 1,000 population (male 94.7, female 99.6), The highest age specific morbidity rate was 274.5 of the 45-to 64-year group and the lowest was 21.9 of the 5-to 14-year group. 2. Annual morbidity rate of the new patients was 777.5 per 1,000 population(male 644.5, female 909.5). 3. The chief complaints distribution of the prolonged ill cases was: local pain 36.6%, indigestion 22.4%, and coughing 7.3%, respectively, In terms of age and sex distribution, a large number of female of the 45-to 64-year group complained of local pain or general pain and a large number of both sexes of the 25-to 44-year group complaned of indigestion. 4. The major diseases of the new patients which classified with International Classfication of Diseases (I.C.D.) were disease of the respiratory system, disease of the digestive system, and disease of the musculo-skeletal system and connective tissue for male, disease of the respiratory system, disease of the digestive system, and accident, poisoning, violence for female. 5. Total ill days of the 92 new patients were 536 days and average ill days per case were $6{\pm}38.3$ days. 6. The rate of receiving treatment in the prolonged ill cases was 82.2%(medical facilities 46.4%, drug stores 27.5%, herb medicine 8.3%). 7. The rate of receiving treatment by first choice of the new patients was 88.0% (drug stores 57.%, medical facilities 28.2%, and herb medicine 2.2%), and the rate of receiving treatment by second choice was 30.9% of first treatment cases (medical facilities 44.0%, drug store 44.0% and herb meicine 12.0%). 8. Annual hospitalization rate per 1,000 population was 12.0 (male 12.0, female 11.9). 9. The locations of medical facilities utilized by out-patients were: in the prolonged ill cases Seoul or other places 66.4%, Nam Yang Ju Gun 33.6%, in cases of the new patients Seoul or other places 35.1% and Nam Yang Ju Gun 64.9% respectively. 10. The satisfaction rate of the new patients by mode of receiving treatment was: in cases of primary utilization by first choice herb medicine 100.0%, medical facilities 88.5%, and drug stores 69.8%, in cases of secondary utilization medical facilities 100.0%, herb medicine 100.0%, and drug stores 72.7% respectively. 11. The medical cost per utilized facilities was as follows; in average medical fee per case out-patient 8.947 won, in-patient 266,000 won, drug stores 1,532 won, and herb medicine 15,607 won, in average medical fee per day out-patient 4,829 won, in patient 14,178 won, drug stores 891 won, and herb medicine 4,906 won respectively. 12. The sources of the hospital charges paid out were: there own expense 50.0%, debt 35.3%, and security of medical care 14.7% respectively.

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Study for the Geochemical Reaction of Ca-feldspar, Amphibole and Olivine with Supercritical $CO_2$ and Brine on the $CO_2$ Sequestration Condition (이산화탄소 지중저장 조건에서 초임계이산화탄소와 염수 반응에 의한 Ca-사장석, 각섬석, 감람석의 지화학적 변화 연구)

  • Kang, Hyun-Min;Park, Min-Ho;Park, Sang-Hee;Lee, Min-Hee;Wang, Soo-Kyun
    • Economic and Environmental Geology
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    • v.44 no.2
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    • pp.123-133
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    • 2011
  • The lab scale experiments to investigate the geochemical reaction among supercritical $CO_2$-mineral-brine which occurs at $CO_2$ sequestration sites were performed. High pressurized cell system (l00 bar and $50^{\circ}C$) was designed to create supercritical $CO_2$ in the cell, simulating the sub-surface $CO_2$ storage site. From the high pressurized cell experiment, the surface changes of Ca-feldspar, amphibole (tremolite) and olivine, resulted from the supercritical $CO_2$-mineral-brine reaction, were observed and the dissolution of minerals into the brine was also investigated. The mineral slabs were polished and three locations on the surface were randomly selected for the image analysis of SPM and the surface roughness value (SRV) of those locations were calculated to quantify the change of mineral surface for 30 days. At a certain time interval, SPM images and SRVs of the same mineral surface were acquired. The secondary minerals precipitated on the mineral surfaces were also analyzed on SEM/EDS after the experiment. From the experiments, the average SRV of Ca-feldspar increased from 2.77 nm to 20.87 nm for 30 days, suggesting that the dissolution of Ca-feldspar occurs in active when the feldspars contact with supercritical $CO_2$ and brine. For the amphibole, the average SRV increased from 2.54 nm to 8.31 nm and for the olivine from 0.77 nm to 11.03 run. For the Ca-feldspar, $Ca^{2+}$, $Na^+$, $Fe^{2+}$, $Si^{4+}$, $K^+$ and $Mg^{2+}$ were dissolved in the highest order and $Si^{4+}$, $Ca^{2+}$, $Fe^{2+}$ and $Mg^{2+}$ for the amphibole. Fe (or Mg) - oxides were precipitated as the secondary minerals on the surfaces of amphibole and olivine after 30 days reaction. Results suggested that $Ca^{2+}$, $Fe^{2+}$ and $Mg^{2+}$ rich minerals would be significantly weathered when it contacts with the supercritical $CO_2$ and brine at $CO_2$ sequestration sites.

[ ${\ulcorner}$ ]Standard Principles for the Designing of Prescriptions - The Theory for Monarch, Minister, Adjuvant and Dispatcher${\lrcorner}$ ("방제구성의 표준적 규격 - 군신좌사(君臣佐使)")

  • Kim Do-Hoy;Seo Bu-il;Kim Bo-Kyung;Kim Gyeong-Cheol;Shin Soon-Shik
    • Herbal Formula Science
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    • v.11 no.2
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    • pp.1-18
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    • 2003
  • The Theory for Monarch, Minister, Adjuvant and Dispatcher (or the Theory of Principal, Assistant, Adjuvant and Guiding Korean Oriental Herbal Medicines) has served as a standard principle for newly developed prescription formulas as well as established ones. Despite its significance, however, this theory hasn't been thoroughly studied and covered in the academic journals of Korean Oriental Herbal Medicines (KOHM) yet. This paper inquires into the origin of the theory while presenting the definitions and functions of Principal, Assistant, Adjuvant, and Guiding KOHM. In the end, the recommended doses and number of the KOHM comprising each of Principal, Assistant, Adjuvant, and Guiding KOHM are suggested. The compatibility theory of Principal, Assistant, Adjuvant, and Guiding KOHM can be traced back to the Warring States Period during which it was recorded in the treatise of the various schools of thoughts and their exponents. The theory was firmly established as a full system in ${\ulcorner}Shinnong's\;Pharmacopoeia{\lrcorner}\;and\;{\ulcorner}Yellow\;Emperor's\;Cannon\;of\;Internal\;Medicine{\lrcorner}$. While ${\ulcorner}Shinnong's\;Pharmacopoeia{\lrcorner}$ focuses on the classification of the properties of KOHM, ${\ulcorner}Yellow\;Emperor's\;Cannon\;of\;Internal\;Medicine{\lrcorner}$ mainly deals with the principles for writing prescriptions. In this regard, it is ${\ulcorner}Yellow\;Emperor's\;Cannon\;of\;Internal\;Medicine{\lrcorner}$ that systemized the Theory of Principal, Assistant, Adjuvant, and Guiding KOHM in a real sense. Principal KOHM aims at the causes of diseases and treat main symptoms. The doses are greater than Assistant, Adjuvant and Guiding KOHM. With their comprehensive effects, Principal KOHM is a leading ingredient of any prescription formula. Assistant KOHM are similar to Principal KOHM in its natures and flavors. Although its natures, flavors as well as efficacies may slightly differ from those of Principal KOHM, Assistant KOHM strengthens the therapeutic effects, jointly working with Principal KOHM. They mainly treat accompanying diseases and symptoms. Adjuvant KOHM is divided into two types: facilitator and inhibitor. Facilitators with the similar properties to those of Principal and Assistant KOHM help strengthen the therapeutic effects. Since they usually treat accompanying symptoms or secondary accompanying symptoms (minor accompanying symptoms), there are two kinds of facilitators. (1) The first kind of facilitators assists Principal KOHM, targeting accompanying symptoms. (2) The second ones supporting Assistant KOHM are for accompanying or secondary accompanying symptoms (or minor accompanying symptoms). Inhibitors counteract and thereby complement Principal and Assistant KOHM. Some of them inhibit the side effects or toxicity of Principal KOHM for the sake of the safety of the whole prescription formula while the others generate induced interactions. Guiding KOHM can be used for two purposes: guiding and mediating. The Guiding KOHM for the former purpose leads the other KOHM in a prescription formula to the lesion. But, the Guiding KOHM for mediating coodinate and harmonize all the ingredients in a prescription formula. The number of KOHM for those Principal, Assistant, Adjuvant and Guiding KOHM and their doses are different, depending on the types of prescriptions: classical prescriptions, prescriptions after ${\ulcorner}$Treatise of Cold-Induced Diseases${\lrcorner}$ and prescriptions of Sasang Constitutions Medicines. In the case of the prescriptions after ${\ulcorner}$Treatise of Cold-Induced Diseases${\lrcorner}$, it is highly recommended to follow the view of ${\ulcorner}$Thesaurus of Korean Oriental Medicine Doctors in Chosun Dynasty${\lrcorner}$ for the number of KOHM to be used. For the doses, however, ${\ulcorner}$Elementary Course for Medicine${\lrcorner}$, is found to be more accurate. The most appropriate number of KOHM per prescription is 11-13. To be more specific, for one prescription formula, it is recommended to administer one kind of KOHM for Principal KOHM, 2-3 for Assistant KOHM, 3-4 for Adjuvant KOHM and 5 for Guiding KOHM. As for the proportion of the doses, when 10 units are to be administered for Principal KOHM in a formula, the doses for the other three should be 7-8 units for Assistant KOHM, 5-6 for Adjuvant KOHM and 3-4 for Guiding KOHM. The doses of the KOHM added to or taken out of the prescription correspond to those of Adjuvant and Guiding KOHM.

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A Study on Salt Removal in Controlled Cultivation Soil Using Electrokinetic Technology (전기동력학 기술을 이용한 시설재배지 토양의 염류제거 효과연구)

  • Kim, Lee Yul;Choi, Jeong Hee;Lee, You Jin;Hong, Soon Dal;Bae, Jeong Hyo;Baek, Ki Tae
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.1230-1236
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    • 2012
  • To verify that the electrokinetic remediation is effective for decreasing salinity of fields of the plastic-film house, field tests for physical property, chemical property, and crop productivity of soils have been conducted. The abridged result of those tests is as follows. In the EK treatment, the electrokinetic remediation has been treated at the constant voltage (about 0.8 V $cm^{-1}$) for fields of the farm household. At this time, an alternating current (AC) 220 V of the farm household was transformed a direct current. The HSCI (High Silicon Cast Iron) that the length of the stick for a cation is 20cm, and the Fe Plate for an anion have been spread out on the ground. As the PVC pipe that is 10 cm in diameter was laid in the bottom of soils, cations descend on the cathode were discharged together. For soil physical properties according to the EK treatment, the destruction effect of soil aggregate was large, and the infiltration rate of water was increased. However, variations of bulk density and porosity were not considerable. Meanwhile, in chemical properties of soils, principal ions of such as EC, $NO_3{^-}$-N, $K^+$, and $Na^+$ were better rapidly reduced in the EK treated control plot than in the untreated control plot. And properties such as pH, $P_2O_5$ and $Ca^{2+}$ had a small impact on the EK. For cropping season of crop cultivation according to the EK treatment, decreasing rates of chemical properties of soils were as follows; $NO_3{^-}$-N 78.3% > $K^+$ 72.3% > EC 71.6% $$\geq_-$$ $Na^+$ 71.5% > $Mg^{2+}$ 36.8%. As results of comparing the experimental plot that EK was treated before crop cultivation with it that EK was treated during crop cultivation, the decreasing effect of chemical properties was higher in the case that EK was treated during crop cultivation. After the EK treatment, treatment effects were distinct for $NO_3{^-}$-N and EC that a decrease of nutrients is clear. However, because the lasting effect of decreasing salinity were not distinct for the single EK treatment, fertilization for soil testing was desirable carrying on testing for chemical properties of soils after EK treatments more than two times. In the growth of cabbages according to the EK treatment, the rate of yield increase was 225.5% for the primary treatment, 181.0% for the secondary treatment, and 124.2% for third treatment compared with the untreated control plot. The yield was increased by a factor of 130.0% for the hot pepper at the primary treatment (Apr. 2011), 248.1% for the lettuce at the secondary treatment (Nov.2011), and 125.4% for the young radish at the third treatment (Jul. 2012). In conclusion, the effect of yield increase was accepted officially for all announced crops.

Survey of Physicochemical Methods and Economic Analysis of Domestic Wastewater Treatment Plant for Advanced Treatment of Phosphorus Removal (총인 수질기준강화를 위한 국내 하수종말처리장의 물리화학적처리 특성조사 및 경제성 분석)

  • Park, Hye-Young;Park, Sang-Min;Lee, Ki-Cheol;Kwon, Oh-Sang;Yu, Soon-Ju;Kim, Shin-Jo
    • Journal of Korean Society of Environmental Engineers
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    • v.33 no.3
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    • pp.212-221
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    • 2011
  • Wastewater treatment plants (WWTPs) are required to meet the reinforced discharge standards which are differentiated as 0.2, 0.3 and 0.5 mg-TP/L for the district I, II and III, respectively. Although most of WWTPs are operating advanced biological phosphorus removal system, the supplementary phosphorus treatment facility using chemical addition should be required almost at all WWTPs. Therefore, water quality data from several exemplary full-scale plants operating phosphorus treatment process were analyzed to evaluate the reliability of removal performance. Additionally, a series of jar tests were conducted to find optimal coagulants dose for phosphorus removal by chemical precipitation and to describe characteristics of the reaction and sludge production. Chemical costs and the increasing sludge volume in physicochemical phosphorus removal process were estimated based on the results of jar tests. The minimum coagulant (aluminium sulfate and poly aluminium chloride) doses to keep TP concentration below 0.5 and 0.2 mg/L were around 25 and 30 mg/L (as $Al_2O_3$), respectively, in the mixed liquor of activated sludge. In the tertiary treatment facility, relatively lower coagulant doses of 1/12~1/3 the minimum doses for activated sludge were required to achieve the same TP concentrations of 0.2~0.5 mg/L. Increase in suspended solids concentration due to chemical precipitates in mixed liquor was estimated at 10~11%, compared to the concentration without chemical addition. When coagulant was added into mixed liquor, chemical (aluminium sulfate) cost was estimated to be 4~10 times higher than in secondary effluent coagulation/separation process. Sludge production to be wasted was also 4~10 times higher than secondary effluent coagulation/separation process.

A Study of Radiation Exposure in Proton Therapy Facility (양성자치료기 가속기 시설에서의 작업종사자의 방사선 피폭 연구)

  • Lee, Sang-Hoon;Shin, Dong-Ho;Yoon, Myong-Geun;Shin, Jung-Wook;Rah, Jeong-Eun;Kwak, Jung-Won;Park, Sung-Yong;Shin, Kyung-Hwan;Lee, Doo-Hyun;Ahn, Sung-Hwan;Kim, Dae-Yong;Cho, Kwan-Ho;Lee, Se-Byeong
    • Progress in Medical Physics
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    • v.20 no.1
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    • pp.37-42
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    • 2009
  • Proton therapy facility, which is recently installed at National Cancer Center in Korea, generally produces a large amount of radiation near cyclotron due to the secondary particles and radioisotopes caused by collision between proton and nearby materials during the acceleration. Although the level of radiation by radioisotope decreases in length of time, radiation exposure problem still exists since workers are easily exposed by a low level of radiation for a long time due to their job assignment for maintenance or repair of the proton facility. In this paper, the working environment near cyclotron, where the highest radiation exposure is expected, was studied by measuring the degree of radiation and its duration for an appropriate level of protective action guide. To do this, we measured the radiation change in the graphite based energy degrader, the efficiency of transmitted beam and relative activation degree of the transmission beam line. The results showed that while the level of radiation exposure around cyclotron and beam line during the operation is much higher than the other radiation therapy facilities, the radiation exposure rate per year is under the limit recommended by the law showing 1~3 mSv/year.

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Microstructural Study of Mortar Bar on Akali-Silica Reaction by Means of SEM and EPMA Analysis (알칼리-실리카 반응에 의한 모르타르 봉의 SEM과 EPMA 분석을 통한 미세구조 연구)

  • Jun, Ssang-Sun;Lee, Hyo-Min;Jin, Chi-Sub
    • Journal of the Korea Concrete Institute
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    • v.21 no.4
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    • pp.531-537
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    • 2009
  • In this study alkali reactivity of crushed stone was conducted according to the ASTM C 227 that is traditional mortar bar test, and C 1260 that is accelerated mortar bar test method. The morphology and chemical composition of products formed in mortar bar, 3 years after the mortar bar tests had been performed, were examined using scanning electron microscopy (SEM) with secondary electron imaging (SEI) and electron probe microanalysis (EPMA) with backscattered electron imaging (BSEI). The crushed stone used in this study was not identified as being reactive by ASTM C 227. However, mortar bars exceeded the limit for deleterious expansion in accelerated mortar bar test used KOH solution. The result of SEM (SEI) analysis, after the ASTM C 227 mortar bar test, confirmed that there were no reactive products and evidence of reaction between aggregate particles and cement paste. However, mortar bars exposed to alkali solution (KOH) indicated that crystallized products having rosette morphology were observed in the interior wall of pores. EPMA results of mortar bar by ASTM C 227 indicated that white dots were observed on the surface of particles and these products were identified as Al-ASR gels. It can be considered that the mortar bar by ASTM C 227 started to appear sign of alkali-silica reaction in normal condition. EPMA results of the mortar bar by ASTM C 1260 showed the gel accumulated in the pores and diffused in to the cement matrix through cracks, and gel in the pores were found to be richer in calcium compared to gel in cracks within aggregate particles. In this experimental study, damages to mortar bars due to alkali-silica reaction (ASR) were observed. Due to the increasing needs of crushed stones, it is considered that specifications and guidelines to prevent ASR in new concrete should be developed.

A Study on Geology of Clay Mineral Deposits of Pohang-Ulsan Area and their Physico-Chemical Properties (포항-울산간의 점토자원의 지질과 그 물리화학적 특성에 관한 연구)

  • Kim, Ok Joon;Lee, Ha Young;Kim, Suh Woon;Kim, Soo Jin
    • Economic and Environmental Geology
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    • v.4 no.4
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    • pp.167-215
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    • 1971
  • I. Purpose and Importance of the Study The purpose of the present study is to clarify to geological, mineralogical, and physico-chemical properties of the clay minerals deposits imbedded in the Tertiary sediments in the areas between. Pohang and Ulsan along southeastern coastal region of Korea. These clays are being mined and utilized for filter and insecticide after activation or simple pulverizing, nontheless activated clays are short coming as chemical industry in Korea has been rapidly grown in recent years. In spite of such increase in clay demand, no goological investigation on clay deposits nor physico-chemical properties of the clays have been carried out up to date. Consequently activated clays produced in Korea is not only of low grade but also of shortage in supply, so that Korea has to import activated clays of better grade. The importance of the present study lies, therefore, on that guiding principle could be laid down by knowing stratigraphical horizons, of clay deposits and fundamental data of improving grade of activated clays might be derived from the results of physico-chemical examinations. II. Contents and Scope of the study The contents of the study are pinpointed down in the following two subjects: 1) General geological investigation of Tertiary formations distributed in the areas between Pohang and UIsan, and detail geological study of the bentonitic clay deposits imbedded in them. 2) To clarifty physico-chemical characteristics of the clays by means of chemical analysis, X-ray diffraction and electron microscope. The scope of the study involves the following there points: i) Regional geological investigation-This investigation has been carried out in order to find out the distribution of Tertiary sediments and exact location of clay mineral deposits in the areas between Pohang and UIsan. ii) Detail geological investigation-This has been concentrated in and around the clay deposits which. had been found out by the regional investigation. iii) Laboratory researchs include i) age determination and correlation of Tertiary sediments by paleontological study, and ii) Chemical analysis, X-ray diffraction, and electron microscopic studies on clays, samples taken from various clay deposits. III. Research Results and Suggestions 1) The geology of the area investigated is composed mainly of Janggi and Beomgokri groups of Miocene age in ascending order rested on the upper Silla system, Balkuksa granite and volcanic rocks of upper Cretaceous age as base. 2) Janggi group is composed in ascending order of Janggi conglomerate, Nultaeri rhyolitic tuff, Keumkwangdong shale, two beds of lignite-bearing formations which consist of alternation of conglomerate, sandstone and mudstone, and andesitic, rhyolitic, and basaltic tuff beds. 3) Beomgokri group is mainly composed of andesitic to rhyolitic tuff interlayered by conglomerate and tuffaceous sandstone. In the areas around boundary between North-and South Kyeongsang-do is distributed Haseori farmation which is composed of conglomerate, sandstone, mudstone and andesitic to rhyolitic tuff, and which is correlated to Eoilri formation of Janggi group. 4) Clay deposits of the area are interbedded in Eoilri, Haseori, Nultaeri tuff, Keumkwangdong shale, upper and lower horizon of the lower lignite-bearing seam, and Keumori rhyolitic tuff formations of Janggi group; and are genetically classi.fied into four categories, that is, i) those derived from volcanic ash beds(Haseori and Daeanri deposits), ii) those of secondary residual type from rhyolitic tuff beds(Seokupri deposits), iii) Clay beds above and beneath the lignite seams, (Janggi and Keumkwangdong deposits), and iv) those derived from rhyolitic tuff beds(Sangjeong and Tonghae deposits). 5) Mineral constituents of clay deposits are, according to X-ray diffraction, montmorillonite accompanied in different degree by cristobalite, plagioclase, quartz, stilbite, and halloysite in rare occasion. The clays are grouped according to mineral composition into four types; i) those consist mostly of montmorillonite, ii) those composed of montmorillonite and cristobalite, iii) those composed of montmorillonite and plagioclase, and iv) those composed of montmorillonite, plagioclase and quartz. 6) Clays interbedded in Haseori formation and vicinity of lignite seams belong to the first type, are of good quality and derived either from volcanic ash bed, or primary clay beds near lignite seams. Clays belonged to other types are derived from weathering of rhyolitic tuff formations and their quality varies depending upon original composition and degree of weathering. Few clays in secondary residual type contain small amount of halloysite. 7) Judging from analytical data, content of silica($SiO_2$) varies proportionally with content of cristobalite, and alumina($Al_2O_3$) content does not vary with that of plagioclase, but increases in the sedimentary bedded type of deposits. 8) It is unknown whether or not these days could be upgraded by beneficiation since no grain size of these impurities nor beneficiation test had been studied. 9) Clay beds derived from valcanic ash layers or sedimentary layers at the vicinity of lignite seams are thin in thickness and of small, discontinueous lenticular shape, although they are of good quality; and those derived from rhyolitic tuff formations or residual type from tuff are irregular in both occurrence and quality. It is, therefore, not only very difficult but also meaningless to calculate its reserve, and reserve estimation, even if done, will greatly be deviated from practically minable one. Consequently, way of discovery and exploitation of clay deposits in the area under consideration is to check the geologically favorable areas whenever needed.

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