• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.141-141
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• 2000

한지의 제조에 있어서 부원료인 점질물은 초지시 매우 중요한 역할을 하는데 그 주된 역 할은 다음과 같다. 먼저 점질물은 섬유의 분산을 용이하게 하고 종이의 강도를 증가시키며, 양지와는 달리 박엽지의 제조가 편리하고, 종이의 경도를 증가시키며, 습지의 처리를 용이하 게 하며, 점성으로 인하여 섬유의 침전올 방지하고, 종이의 광택을 향상시키는 둥 매우 중요 한 역할을 한다. 그러나 한지 제조시 이러한 식물성 점제의 미묘한 작용은 현재 대다수의 한지 제조 공장에서 사용하고 있는 합성점제인 PAM이나 PEO 등의 합성 고분자 화합물에 서는 기대하기 어려운 작용이라 여겨진다. 이와 같은 사실에서 본 연구에서는 전통적인 천 연점질물인 황촉규근의 점질물과 합성점제인 PAM 및 우리 나라에서 전혀 사용되지 않고 있는 나무수국 내수피의 점질물을 이용하여 한지를 제조하고 이들 한지의 특성을 SEM 및 A AFM(Atomic Force Microscopy)를 이용하여 분석하였다. 먼저 각각의 점질물로 제조한 한지를 SEM으로 관찰한 결과 닥나무 인피섬유의 최외층에 투명막이 존재하는 사실을 발견할 수 있었다. 이러한 투명막은 닥나무나 뽕나무 인피섬유에 만 존재하고 삼지닥나무나 산닥나무 둥과 같은 기타 인피섬유에는 존재하지 않으므로 한지 의 원료 섬유의 식별에 매우 중요한 요소가 된다. 또한 이러한 투명막은 섬유간 결합을 증 대시켜 한지의 강도 발현에 기여한다고 사료된다. 천연점질물인 황촉규근과 나무수국 점 질물을 이용하여 제조한 한지를 SEM 및 SEM-EDXA를 이용하여 분석한 결과, 황촉규근 점질물로 제조한 한지에는 상당량의 전분입자가 폰재하고 있었으며 나무수국 점질물로 제 조한 한지에는 침상의 수산칼슐 결정이 상당량 존재하고 있는 사실을 발견하였다. 이러한 사실은 한지 제조시 사용된 점질물의 식별에 중요한 요소라 사료된다. 한지의 원료인 닥나무 인피펄프와 침엽수 미표백 크라프트 펄프를 AFM을 이용하여 분석 한 결과, 닥나무 인피펄프의 마이크로피브릴 폭은 5-10nm로 Sw-UKP의 마이크로피브릴 폭 lO-20nm보다 매우 가늘고, 치밀한 세포벽 구조를 하고 있었다. 닥나무 인피펄프의 이러 한 세포벽 구조 및 마이크로피브렬의 형태가 Sw-UKP보다 높은 섬유강도를 나타내는 원인 이라 사료된다. 각각의 점질물을 이용하여 제조한 한지의 섬유표면을 AFM을 이용하여 관 찰한 결과, 원료펄프의 표면관찰에서와는 달리 초지시 사용된 점질물이 섬유표면을 피복하 고 있어 명확한 형태의 마이크로피브렬을 관찰할 수 가 없었다. 따라서 점질물의 이러한 역 할이 한지의 강도 및 보존성 향상에 기여하리라 사료된다.

• Journal of Environmental Science International
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• v.33 no.2
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• pp.161-168
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• 2024

This study was conducted to identify the pollutants generated by the fuel complex and to determine the health effects of the surrounding residents. In addition, based on the results of epidemiological surveys and health impact surveys of local residents, we analyze the distribution of patient groups and exposure characteristics according to the distance from the fuel complex boundary. Samples were collected from the briquette plant within the fuel complex and analyzed by SEM-EDXA, X-ray Fluorescence Spectrometer, and ICP. In addition, the distribution of patients and exposure characteristics were analyzed according to the distance from the fuel complex and yard boundaries. Analysis of briquette samples from the fuel complex showed that the average particle size was 10-30 ㎛, the shape was irregular, and SiO₂ accounted for more than 50%. It is believed that silica, which causes pneumoconiosis, may have been scattered into the air. In particular, there was a large distribution of 5 ㎛ particles that affect respiratory diseases. According to the analysis of the residential addresses and distribution of pneumoconiosis cases, many pneumoconiosis cases were located in the area between 200 and 500 meters from the boundary of the fuel complex. In addition, 28 pneumoconiosis cases were identified as a result of the epidemiological survey and health impact survey at the fuel complex. In detail, there were 8 cases of occupational pneumoconiosis, 6 cases of environmental pneumoconiosis, and 14 cases of occupational and environmental pneumoconiosis. The confirmed pneumoconiosis cases were located between 0.3 and 1.1 kilometers from the fuel complex. It was found that environmental pollutants generated by the fuel complex adversely affect the health of local residents. In particular, there are many cases of pneumoconiosis in the area between 200 and 500 meters from the boundary of the fuel complex, and this distance is considered to be the direct and indirect impact zone of the briquette plant.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.146-156
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• 1998

Fly ash produced in coal combustion is a fine-grained material consisting mostly of spherical, glassy, and porous particles. A physical, morphological, and chemical characteristic of fly ash has been analyzed. This study may contribute to the data base of domestic fly ash, the improvement of combustion efficiency, ash recycling and ash collection in the electrostatic precipitator. The physical property of fly ash is determined using a particle counter for the measurement of ash size distribution and gravimeter. Morphological characteristic of fly ash is performed using a scanning electron micrograph and an optical microscope. The chemical components of fly ash are determined using an inductively coupled plasma emission spectrometry (ICP). The distribution of fly ash size was ranged from 15 to 25 $\mu$m in mass median diameter. Exposure conditions of flue gas temperature and duration within the combustion zone of the boiler played an important role on the morphological properties of the fly ash such as shape, relative opacity, coloration, cenosphere and plerosphere. The spherical fly ash might be generated at the condition of complete combustion. The size of fly ash was found to be increased the with particle-particle interaction of agglomeration and coagulation. Fly ash consisted of $SiO_2\;Al_2O_3\;and\;Fe_2O_3$ with 85% and carbon with 3~10% of total mass.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.213-232
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• 2009

This document was prepared to review and summarize the analytical methods for airborne and bulk asbestos. Basic principles, shortcomings and advantages for asbestos analytical instruments using phase contrast microscopy(PCM), polarized light microscopy(PLM), X-ray diffractometer (XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM) were reviewed. Both PCM and PLM are principal instrument for airborne and bulk asbestos analysis, respectively. If needed, analytical electron microscopy is employed to confirm asbestos identification. PCM is used originally for workplace airborne asbestos fiber and its application has been expanded to measure airborne fiber. Shortcoming of PCM is that it cannot differentiate true asbestos from non asbestos fiber form and its low resolution limit ($0.2{\sim}0.25{\mu}m$). The measurement of airborne asbestos fiber can be performed by EPA's Asbestos Hazard Emergency Response Act (AHERA) method, World Health Organization (WHO) method, International Standard Organization (ISO) 10312 method, Japan's Environmental Asbestos Monitoring method, and Standard method of Indoor Air Quality of Korea. The measurement of airborne asbestos fiber in workplace can be performed by National Institute for Occupational Safety and Health (NIOSH) 7400 method, NIOSH 7402 method, Occupational Safety and Health Administration (OSHA) ID-160 method, UK's Health and Safety Executive(HSE) Methods for the determination of hazardous substances (MDHS) 39/4 method and Korea Occupational Safety and Health Agency (KOSHA) CODE-A-1-2004 method of Korea. To analyze the bulk asbestos, stereo microscope (SM) and PLM is required by EPA -600/R-93/116 method. Most bulk asbestos can be identified by SM and PLM but one limitation of PLM is that it can not see very thin fiber (i.e., < $0.25{\mu}m$). Bulk asbestos analytical methods, including EPA-600/M4-82-020, EPA-600/R-93/116, OSHA ID-191, Laboratory approval program of New York were reviewed. Also, analytical methods for asbestos in soil, dust, water were briefly discussed. Analytical electron microscope, a transmission electron microscope equipped with selected area electron diffraction (SAED) and energy dispersive X-ray analyser(EDXA), has been known to be better to identify asbestiform than scanning electron microscope(SEM). Though there is no standard SEM procedures, SEM is known to be more suitable to analyze long, thin fiber and more cost-effective. Field emission scanning electron microscope (FE-SEM) imaging protocol was developed to identify asbestos fiber. Although many asbestos analytical methods are available, there is no method that can be applied to all type of samples. In order to detect asbestos with confidence, all advantages and disadvantages of each instrument and method for given sample should be considered.