• 한국세라믹학회지
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• 제40권12호
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• pp.1141-1149
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• 2003

Refractory industry in technologically advanced countries has long been on gradual decline due to leveled-off steel production and decreasing unit consumption of refractories for steel. Notable technological achievements by refractory industry that contributed significantly to steel production are briefly reviewed covering from blast furnace, basic oxygen furnace to continuous casting. Future possibility to revitalize the refractory industry is discussed on the basis of the review, taking into account opportunities available in environment and energy related sector of industries.

• 한국습지학회지
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• 제25권4호
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• pp.221-229
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• 2023

수도권에 일 약 8백만톤의 물을 취수하여 공급하는 팔당호는 수질보전정책 시행으로 BOD(Biochemical Oxygen Demand)1.1mg/L를 달성하였으나 난분해성 물질을 포함하는 COD(Chemical Oxygen Demand) 항목은 점점 증가하는 양상을 보였다. 난분해성 유기물질의 상수원 유입은 잠재적인 BOD의 증가, 수돗물의 냄새와 맛 유발, THM(Trihalomethane) 발생 증가, 조류 증식을 일으키며 유해 난분해성 미량오염물질이 잔류할 경우 수생 환경에서 내분비 교란과 항생제 내성과 같은 현상을 유발한다. 본 연구에서는 팔당호의 난분해성 유기물질 관리를 위해 팔당호와 팔당호 상류의 점 오염원과 비점오염원의 난분해성 유기물질 유출 농도를 파악하기 위한 모니터링을 실시하였다. 지역별 난분해성 유기물질 유출 농도를 비교하고 하수처리장에서의 제거율을 파악하였다. 또한 피어슨 상관성 분석 기법을 사용해 유기물질 지표와 선행건기일수, 선·선행건기일수간 상관성 분석을 실시하였다. 하천과 팔당호의 난분해성 유기물질 농도는 유사한 양상을 보였다. 하수처리장 유출수는 하천과 팔당호보다는 높은 농도를 보였으며, 유입수와 유출수 농도의 비교 결과 하수처리장에서 난분해성 유기물질 제거율은 65.73%였다. 난분해성 유기물질 유출 농도와 선행건기일수, 선·선행건기일수 사이에서는 유의미한 상관성이 나타나지 않았다. 이는 데이터 부족으로 판단되며 장기적인 모니터링으로 데이터 축적이 필요하다 사료된다.

• 세라미스트
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• 제9권6호
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• pp.12-17
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• 2006

One of characteristic of $Cr_2O_3-containing$ refractory is excellent resistance to corrosion. However, there is a problem that hexa-valent chromium, which is noxious to the human body, is easily formed by reaction between the refractory and slag with CaO, $Na_2O$ and/or $K_2O$. In this article, the reason why the $Cr_2O_3-containing$ refractory has excellent corrosion resistance qualities, he conditions under which hexa-valent chromium formed, methods for suppressing generation of hexa-valent chromium and the possibility of the refractory components excluding $Cr_2O_3$ for the furnace are described as a base of development of further excellent refractories.

• 한국물환경학회지
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• 제27권3호
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• pp.306-313
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• 2011

In this paper, runoff characteristics of South-Han river watershed in terms of refractory organic matters were investigated. The concentrations of DOC, POC, R-DOC, R-POC in runoff and flow rates were determined by monitoring 27 times in dry season and 4 times in rainy season. The concentrations of the dissolved refractory organic matter, R-DOC was the lowest in fall and similar in the other dry seasons. The particulate refractory organic matter, R-POC showed less fluctuation than R-DOC. In summer, mass loading was the highest than other dry seasons. The concentrations of R-DOC, R-POC were showed to be affected by runoff volume. The mass loading grows higher as runoff volume gets higher.

• 대한한의학회지
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• 제43권2호
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• pp.110-116
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• 2022

Objectve: To inform a clinical usefulness of Nangan-geon (暖肝煎) decoction to treat a refractory abdominal pain especially in eldery. Methods: This case report presents an 85-year old male patient who had been suffered with a refractory abdominal pain without any abnormality in laboratory test and radiological examination for 5-years. The clinical outcome was observed by numerical rating scale (NRS) of self-reporting method. Results: Based on his previous multiple normal examination results from Western hospitals and clinical features including thin body (19.6 BMI), nocturnal pain around lower abdomen and cold-sensitivity, author diagnosed him as "deficiency and cold of liver-Qi (肝氣虛寒)" similar to intestinal spasm. After prescription with Nangan-geon (暖肝煎) for one month, all symptoms became improved notably (NRS 5), and almost completely recovered as a level of normal condition in 3 months (NRS 1). Conclusion: This study would show the potential of traditional Korean medicine (TKM) therapies for a refractory functional abdominal pain, and especially efficacy of Nangan-geon against cold-pattern of nonspecific abdominal pain in elderly patients.

• The Korean Journal of Ceramics
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• 제1권2호
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• pp.86-90
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• 1995

Theoretical predictions for thermodynamically stable phases which formed when alkali(sodium and potassium) vapors reacted with alumina-chromia refractories under coal gasifying atmosphere were confirmed experimentally using a laboratory-scale coal gasifying reaction system and a commercial alumina-chromia refractory using SEM, XRD, and EDAX. Alkali concentration profiles in the refractory as a function of time were also determined. The results showed that the compounds that formed were $X_2O{\cdot}Al_2O_3, X_2O{\cdot}Cr_2O_3, X_2O{\cdot}5Al_2O_3, X_2O{\cdot}7Al_2O_3, X_2O{\cdot}11Al_2O_3(X=Na^+ \;or\; K^+)$, depending upon the alkali concentration and time of exposure at high temperatures. The presence of sulfur in gasifying atmospheres did not appear to affect the alkali reaction produces. Alkali pentration into the alumina-chromia refractory was deep and the formation of the $Na_2O{\cdot}Al_2O_3/K_2O{\cdot}Al_2O_3$ compunds resulted in the serious deformation of the refractory due to the large volume expansion at the reaction surface. The hot face of the alumina-chromia refractory in service under an alkali environment is prone to failure by alkali attack.

• 대한견주관절학회:학술대회논문집
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• 대한견주관절학회 2009년도 제17차 학술대회
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• pp.208-208
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• 2009

Eleven shoulders (9 patients) with refractory scapulothoracic dysfunction were treated with scapulothoracic arthrodesis between 2000 and 2006. Refractory shoulder dysfunction included facioscapulohumeral muscular dystrophy in five shoulders (3 patients), refractory scapular winging with long thoracic nerve palsy in one shoulder, scapular winging caused by serratus anterior palsy with trapezius dysfunction in one shoulder, post-surgical thoracic outlet syndrome due to medial clavicle resection in two shoulders, refractory scapular winging with spinal accessory nerve injury in one shoulder, and chronic trapezius rupture caused by cervical spine surgery in one shoulder. The mean active flexion was improved from 82 degrees preoperatively to 112 degrees postoperatively. The mean Constant score was improved from 27.2 points to 68.0 points. Two shoulders (1 patient) that had facioscapulohumeral muscular dystrophy had broken wires due to nonunion, and one patient had a reactive pulmonary effusion. In ten of the eleven shoulders, the patients were satisfied with their results. The scapulothoracic arthrodesis can cause significant pain relief and functional improvement in refractory scapulothoracic and/or shoulder dysfunction. By selecting patients that present with appropriate indications, and using experienced surgical technique through complete preoperative evaluation, we can diminish the complication rate and make good clinical outcomes.

• 한국물환경학회지
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• 제29권3호
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• pp.393-399
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• 2013

To control organic matters, it needs to manage not only biodegradable organic matters but also refractory organic matters. Refractory organic matters from municipal wastewater, industrial wastewater, non-point sources and etc., have been continuously discharged to the near watersheds. It is estimated that the refractory organic matter ratios are continuously increased in waterbody. In watersheds of the Total Maximum Daily Loads (TMDLs), it was investigated that COD/BOD ratios increased in many unit watersheds of the 4 major river basins. The portions COD/BOD ratios increased were found to be a 97% of Geum River unit watersheds, a 81% of Yeongsan/Seumjin River unit watersheds, a 78% of Nakdong River unit watersheds, a 70% of Han River unit watersheds, respectively. Therefore, it has become important for establishment of effective management strategies to control refractory organic matter in watersheds of the Total Maximum Daily Loads (TMDLs). In order to properly manage organic matters including refractory organic matters, the present organic indicator (BOD) has to be converted to TOC (or COD). Compared to COD and BOD, TOC, as a organic matter indicator, is evaluated more appropriate.

• 대한한방내과학회지
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• 제38권6호
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• pp.1085-1095
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• 2017

Objectives: The purpose of this study was to investigate the efficacy of Lijin-tang-gamibang on refractory gastroesophageal reflux disease (GERD). Methods: This before-and-after study compared the first medical examination and examination at the end of medical treatment. Twelve refractory GERD patients who visited the Department of Digestive Diseases of Kyung Hee University Korean Medicine Hospital from August 14th, 2017 to October 14th, 2017, were treated with Lijin-tang-gamibang for four consecutive weeks. The clinical characteristics of refractory GERD and the efficacy of herbal medical treatment was assessed by questionnaires, the Nepean Dyspepsia Index-Korean version (NDI-K), the Korean Gastrointestinal Symptom Rating Scale (KGSRS), the Numerical Rating Scale (NRS), the Korean version of the Perceived Stress Scale (KPSS-10), the Qi Stagnation Questionnaire (QSQ), the Spleen Qi Deficiency Questionnaire (SQDQ), and the Patient Global Impression of Change (PGIC). Prolonged effects were reported upon the follow-up telephone survey two weeks after treatment. Results: After treatment with the herbal medicine Lijin-tang-gamibang, the clinical characteristics of 12 refractory GERD patients were improved, especially in terms of the most common symptoms of acid regurgitation and heartburn. Each symptom score of NDI-K, KGSRS, NRS, SQDQ, and PGIC showed significant advances. Prolonged effects were reported in NDI-K, NRS and PGIC questionnaires two weeks after treatment. Conclusions: These results suggest that Lijin-tang-gamibang is an effective treatment for refractory GERD.