아연계 탈황제의 장기연속 반응성 연구

박노국,이종욱,이승철,이종대,류시옥,이태진 영남대학교 공업기술연구소 2000 工業技術硏究所論文集 Vol.28 No.2

The zinc titanate sorbents(ZTG40) were prepared and the tests for durability and attrition resistance were carried out to develop the highly effective desulfurization sorbents. In the attrition tests for ZTG40 the results showed that the attrition resistance was 94.08% and that the sulfur capacity was maintained above 15g S/100g sorbent throughout the 100-cycle test, its maximum being 23.05g S/100g sorbent. As compared to sorbents developed by the developed countries, ZTG40 showed superior performances. In the advanced countries 15g S/100g sorbent is a yardstick of excellency for the sulfur capacity of desulfurization sorbents. Therefore, ZTG40 developed in this study has the desirable physical and chemical properties for fluidized desulfurization of coal gases.

Firmware Design for Portable PCR Devices Controlled by Smart Phones through Wireless Communication

Wan Yeon Lee1,Min Ja Kim,YoungWoong Ko,Jong Dae Kim 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.11

In this paper, we design and implement a firmware for portable PCR devices that is controlled by a smart phone. The firmware has the host-local structure in which the firmware receives operation commands from the smart phone and sends operation results to the smart phone through Bluetooth communication. The firmware is designed to accommodate unstable wireless communication of Bluetooth. We implement a low-cost small PCR device with the proposed firmware on microchip PIC18F4550, and verify that the implemented PCR device significantly re

Toluene, Xylene, Trichloroethylene 투여가 흰쥐의 시상하부와 뇌하수체의 GnRH, GnRH Receptor, Pit-1 유전자 발현에 미치는 영향

기노석,이종태,강대성,김대환,이채관,이헌,전진호,김정호,이채언 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.2

The workplace exposure of chemicals has steadily increased, therefore the concern for subsequent effect on reproductive outcome has been an important issue in occupational medicine. In previous studies, higher rates of spontaneous abortion, reduced fertility and menstrual disorder among women, and an impairement of sperm quantity and quality among men have been associated with a wide variety of chemical agents. This study was conducted to evaluate the effects of toluene, xylene and trichloroethylene(TCE) injection on the mRNA levels of GnRH, GnRH receptor and Pit-1 genes in male rats hypothalamus and pituitary and the effects on the plasma levels of FSH, LH, prolactin and testosterone. Sprague-Dawley male rats were divided into five groups of five each according to concentration of toluene, xylene and TCE. The rats were injected subcutaneously to 0, 50, 100, 200, 400 mg/kg body weight/day of toluene, xylene and TCE, respectively for 6 days. Rat brains were excised and hypothalamus and pituitary were separated. Reverse transcription-polymerase chain reaction (RT-PCR) and RNase protection assay(RPA) were used to evaluate the GnRH, GnRH receptor and Pit-1 mRNA levels. Plasma concentrations of FSH, LH, prolactin and testosterone were assayed by radioimmunoassay(RIA). The results were as follows; 1. GnRH, GnRH receptor and Pit-1 mRNA levels in toluene and xylene injected groups, and GnRH receptor mRNA levels in TCE injected group were lowered dose-dependently. Especially, GnRH receptor and Pit-1 mRNA levels in 200mg/kg of toluene injected group, and GnRH, GnRH receptor and Pit-1 mRNA levels in 400mg/kg of toluene injected group were significantly lower than control group (p<0.05). GnRH receptor and Pit-1 mRNA levels in 400mg/kg of xylene injected group, and GnRH receptor mRNA levels in 400mg/kg of TCE injected group were significantly lower than control group(p<0.05). 2. The plasma levels of prolactin and testosterone in 400mg/kg of toluene injected group, and LH in 100, 200 and 400mg/kg of xylene injected group, and testosterone in 400 mg/kg of TCE injected group were significantly lower than control group(p<0.05). In conclusion, we speculated that toluene and xylene affected reproductive system secondarily through hypothalamus-pituitary axis, and TCE affected directly through steroidogenesis. And we recommended that further study for assessment of the reproductive toxicity of mixed organic solvent exposures should be conducted.

Discordance in Spirometric Interpretations Based on Korean and Non-Korean Reference Equations

Nami Kim,Mi-Hee Park,Se-yeong Kim,Chunhui Suh,Sangyoon Lee,Kun-Hyung Kim,Chae-Kwan Lee,Dae-Hwan Kim,Jong-Tae Lee 대한직업환경의학회 2013 대한직업환경의학회지 Vol.25 No.-

Objectives: Korean regression models for spirometric reference values are different from those of other ethnic groups. The purpose of this study was to evaluate discordance in spirometric interpretations based on using Korean reference equations versus non-Korean reference equations. Methods: Spirometry was performed on 825 Korean male workers from April 2009 to November 2011. The spirometric patterns and disease severity were evaluated using two Korean equations (Choi’s and Lee’s) and three equations for Caucasians (NHANES III, Morris’s, and Knudson’s), and the results of Choi’s equation were compared with the non-Korean equations. The spirometric patterns were defined as normal, restrictive, and mild and moderate obstructive. Results: The mean differences in the FEV1% and FVC% between the two Korean equations were 2.0 ± 1.3% and 3.5 ± 2.2%, respectively. Morris’s equation had the greatest difference in the FEV1% from Choi’s equation: 32.9 ± 8.5%. Knudson’s equation had the greatest difference in the FVC% from Choi’s equation: 10.5 ± 6.5%. Conclusions: The two Korean equations shared similar characteristics of spirometric interpretation. The spirometric interpretations of Choi’s equation were significantly different from those of Morris’s equation and Knudson’s equation.

섬유강화 고분자 복합판의 기계적 성질에 미치는 섬유길이와 섬유함유율의 영향

이상동,김혁,허업,최종대,이동기 조선대학교 에너지.자원신기술연구소 1997 에너지·자원신기술연구소 논문지 Vol.19 No.2

This paper describes effect of chopped strand length fiber content and moisture absorption on mechanical properties of fiber-reinforced polymeric composites. It was extrusion compounded long fiber-reinforced polypropylene containing 20, 30 and 50 percent and short fiber-reinforced ABS and PAS containing 30 percent b37 the weight of glass fiber. The test methods of ASTM D638, D3410-87 and D79OM are applied for tensile, compressive and bending tests respectively. The results show that, in the case of 0.2% moisture absorption, the residual strength decreases dramatically.

Ti-6Al-4V합금의 열처리가 피로균열진전특성에 미치는 영향

이종형,강용구,황은하,최성대 金烏工科大學校 産業技術開發硏究院 1999 産業技術開發硏究 Vol.15 No.-

The fatigue crack growth test under constant amplitude loading was carried out to assess the effect of heat treatment on the fatigue crack growth of a forged Ti-6Al-4V alloy. Prepared with different heat treatment i.e.annealed at 850˚C(AN), 1100˚C(β-AN) and solution treated and aged(STA). Emphasis was placed on the effect of microstructure on fatigue behaviour, in particular, fatigue crack growth and crack closure and crack deflection and roughness of fatigue fracture surface. Fractographic observation was performed using a scanning electron microscope(SEM) for fatigue fracture surface.

限界水路傾斜法을 이용한 網狀河川의 흐름특성 비교

李大澈,이종석,金二顯 大田産業大學校 1996 한밭대학교 논문집 Vol.13 No.1

This study is in comparison the theoretical calculated values by the critical channel slope method with the field measured data in a braided channel. A consequence by the dimensional analysis showed to 3 dimensionless variable quantities one of the 6 variables, tractive force, particle size, water and sediment density, gravity acceleration and dynamic viscosity, related to transport of sediment particles. As a study channel reach we chose a small part of MIHO river which is a well developed braided channel in tributary of the KUM river catchment area, and it divided into 25 sections to the channel reaches 4,680m. Theoretical critical channel slope appeared at the section No. 21 and the meandering channel from began to appear instead of braided form at near section No.23 downstream about 320m from section No.21. And also the critical channel slope was 1/1,591 in theory but in field it is 1/1,613.

근위부 후하소뇌동맥의 자연박리성 동맥류 1예

구본대,이종호,김상범,이계훈,허경,이병희 대한신경과학회 1999 대한신경과학회지 Vol.17 No.5

식물성 식품중 총플라보노이드 함량과 생리활성 탐색

이종미,손은심,오상석,한대석 한국식생활문화학회 2001 韓國食生活文化學會誌 Vol.16 No.5

The contents of total flavonoids, total antioxidant status and superoxide scavenger activity of edible plants were measured. Among twenty one samples of leafy vegetables and teas, mugwort (Artemesia capillaris) and green teas gave high total flavonoids contents, 48.2㎎/g sample and 44.7㎎/g sample, respectively. The highest concentration of total flavonoids among eighty nine samples analyzed was 52.1㎎/g sample from propolis. When samples were tested for total antioxidant status, a kind of groundsel showed the highest Total Antioxidant Status(TAS) value, 13.4 mM among leafy vegetables and teas and green tea gave high TAS value, 11.84 mM. On the other hand, purslane gave the lowest TAS value, 0.01 mM. The superoxide scavenge activity was measured from the extracts of all edible plants. The superoxide scavenge activity of polygonatum (81.1%) and chrysantemum (78.5%) were the highest among leafy vegetables, teas and medicinal plants. On the other hand, ginseng, poria, cassiae semen and dioscoreae rhizoma showed no superoxide scavenge activities.

하악골에 발생한 거대한 cemento-ossifying fibroma의 치험례

이상철,권용대,이백수,김여갑,류동목,박종오 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

The cemento-ossifying filbroma is a well-demarcated and occasionally encapsulated neoplasm composed of fibrous tissue that contains varying amounts of calcified tissue resembling bone, cementum, or both. The greatest number of cases are encountered during the third and fourth decades of life and there is a definite female predilection, with female-to-male ratios as high as 5 : 1 being reported. The mandible is involved far more than the maxilla, and 90 percent of all cases are located in the mandible. The mandibular premolar-molar area is the most common site. Radiographically, the lesion is most often well defined and unilocular. Depending on the amount of calcified produced in the tumor, it may appear as completely radiolucent : more often it shows varying degrees of radiopacity. Some lesions may be largely radiopaque with a radiolucent halo. On microscopic study, the tumor is composed of fibrous tissue of varying degrees of cellularity containing calcified material. This may be in the form of trabeculae of osteoid and bone or basophilic ovoid calcifications that resemble cementum-like material. Admixture of the two types of calcifications are commonly seen. On this case, large cemento-ossifying fibroma has grown in the mandible and this lesion was treated by complete surgical excision and posterior iliac bone graft. A review of literature and a report of a case of cemento-ossifying fibroma are presented.