• Journal of Korea Far Infrared Association
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• s.24
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• pp.32-37
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• 2005

공기이온에 관한 연구는 많은 분야의 연구원 참여에 의해 폭넓게 알려져, 반세기에 이르는 번영의 역사를 쌓아 왔지만, 불가사의하게도 현재, 가장 중요한 적용분야인 보건 분야에서 위기를 맞고 있다. 20세기 초, 대기 중에 전하를 띤 입자의 존재가 관찰된 이래, 공기 이온의 성질을 문제로 한 기초적 연구가, 간단한 공기이온계측기 보급과 함께, 물리학자, 생물학자, 의학자의 협력 하에 1930년대 이후 활발히 이루어져, 공기이온의 위생적ㆍ치료적 가치에 대한 풍부한 정보를 얻을 수 있게 되었다. 어찌되었든 이온화환 공기 속에서는 생활할 수 없는 것이 확실해져, 어떤 농도의 공기이온은 사람 및 동물의 생체에 유익한 작용을 하고, 대용량 공기이온은 치료에 적용가능하지만, 농도의 여하에 관계없이, 양이온이 음이온에 비해 2~3배 우세하면, 신체의 상태를 악화시켜며, 또한 공조설비와 필터류는 모두 이온화작용을 나타내는 것도 밝혀졌다. 청정한 공기를 이온화하는 것은 산소, 탄산가스, 약용물질분자를 활성화시키지만, 오염된 공기의 이온화는 유독한 불순물의 독성을 증가시키는 점도 지적되었다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.4 no.2
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• pp.72-81
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• 1992

Experimental study on air ionization phenomena has been conducted to analyze the propagation behavior and dischargeability of polarity air ions under the super clean room environments with the operation of prototype of Air Ionization System. Varying humidity and air velocity, the distribution of air ion density and the discharge time are measured and analyzed.

• Air Cleaning Technology
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• v.2 no.4 s.8
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• pp.22-26
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• 1990

• Journal of radiological science and technology
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• v.30 no.2
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• pp.147-151
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• 2007

AAPM TG43 report has recommended to measure air kerma strength with the strength of source. Main purpose of this study is to verify the accuracy of air kerma strength provided by manufacturer. Materials for this study were MAX-4001 Electrometer, HDR 1000 Plus of the corporation of standard imaging, and 6 french bronchial Applicator with 1000 mm. we measured ionization current in 10-90 mm range from the bottom of the central axis of chamber. The reference point of calibration displayed by the maximum ionization current in the ionization current curve was measured, and air kerma strength was computed from the maximum ionization current. we acquired 50 mm distance to correspond with the maximum ionization current in the ionization current curve. Its distance has perfectly fitted to the source reference point of calibration certificate of UW-ADCL. Air kerma strength computed value has measured about 0.5% more than calibration value provided by manufacturer. Air kerma strength of calibration certificate provided by manufacturer has acquired reliable results. This study shows that considering the move error of dwell position of source and the dead space length in well-type chamber is a good way to get an accurate result.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.11a
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• pp.134-137
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• 2005

공기중 미세먼지에서 인체의 호흡경로에 따른 수용성 무기이온성분의 침착특성을 파악하기 위하여 익산지역에서 2004년 10월 17일부터 11월 2일까지 앤더슨샘플러를 사용하여 하루주기로 공기중 미세먼지를 입도별로 분급포집한 후 수용성 무기이온성분을 정량화하여 분석하였다.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.167-172
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• 2003

액정판넬(LCD) 및 반도체 제조공정에 있어서 정전기 발생으로 인하여 미세한 먼지가 LCD 및 반도체 웨이퍼에 부착되거나, 정전기 방전에 의해 반도체소자 및 LCD 유리기판상의 패헌의 파괴를 야기하여 제품의 수율을 저하시키고 제조원가를 상승시키는 주요한 요인이 된다. 현재 이러한 제조공정에서 정전기를 위한 대책으로 코로나방전에 의한 이온바(Ion Bar) 및 이온브로어(Ion Blower)를 제전설비로 사용하고 있으나, 이 장치는 코로나 방전에 의한 이온을 발생시키고 이온화된 공기를 불어 내기 위하여 팬을 사용하여 공기를 대류 시킨다.(중략)

• Proceedings of the KIPE Conference
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• 2015.11a
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• pp.175-176
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• 2015

봄철 황사나 대기오염으로 인하여 실내에 오염된 공기가 유입되고 있다. 이를 정화하기위해 현재 실내에서는 공기청정기를 사용한다. 그러나 기존의 공기청정기는 이미 실내공기가 오염되었을 때 작동한다. 이를 보완하고자 본 논문에서는 방충망형 오염공기 차단기를 제안하였다. 방충망형 오염공기 차단기는 방충망에 고압의 DC 전압을 인가하여 코로나현상을 일어나게 하도록 만든 장치이다. 코로나 현상이 일어나면 주변 공기가 이온화 되는 원리를 이용하였다. 고압의 DC 전압을 발생시키기 위해 Full-Bridge 인버터를 이용하여 LC공진으로 변압기의 1차측 전압을 상승시켰고, 권선비를 이용하여 변압기 2차측 전압을 승압하였다. 마지막으로 배전압 정류회로를 설계하여 최종 DC전압을 생성하였다. 실험을 통해 제안한 방식의 유용성을 검증하였다.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.11
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• pp.965-974
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• 2009

This study evaluated the degradation efficiency of malodorous sulfurized-organic compounds by utilizing N- and Sdoped titanium dioxide under visible-light irradiation, and examined the catalyst deactivation and regeneration. Catalyst surface was characterized by employing Fourier-Transform-Infrared-Red (FTIR) spectra. The visible-light-driven photocatalysis techniques were able to efficiently degrade low-level dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) with degradation efficiencies exceeding 97%, whereas they were not effective regarding the removal of high-level DMS and DMDS, with degradation efficiencies of 84 and 23% within 5 hrs of photocatalytic processes. As compared with DMS, DMDS which containes one more sulfur element revealed quick catalyst deactivation. Catalyst deactivation was confirmed by the equality between input and output concentrations of DMD or DMDS, the obsevation of no $CO_2$ generation during a photocatalytic process, and the FTIR spectrum peaks related with sulfur ion compounds, which are major byproducts formed on catalyst surfaces. The mineralization efficiency of DMS at 8 ppm, which was a peak value during a photocatalytic process, was calculated as 144%, exceeding 100%. The catalyst regenerated by high-temperature calcination exhibited higher catalyst recovery efficiency (53 and 58% for DMDS and DMS, respectively) as compared with dry-air and humid-air regeneration processes. However, even the calcined method was unable to totally regenerate deactivated catalysts.

• Journal of the Korean Ceramic Society
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• v.35 no.3
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• pp.209-218
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• 1998

Ca-deficiency frequently observed in the hydroxyapatite powders prepared by precipitation which is known to be deleterious for its application to biomaterials was prevented by the technique developed in this study. In addition the prepared powder has been revealed to be quite active that full density is achieved at temperatures as low as 100$0^{\circ}C$ Instead of using N2 air was chosen as the processing atmosphere during the precipitation and aging of hydroxyapatite. {{{{ {CO }`_{3 } ^{2- } }} ions from the processing atmosphere(air) substitute partly for {{{{ {PO }`_{4 } ^{3- } }} ions in the hydroxyapatite and its content can be controlled by pH of the solution where the pre-cipitation reaction occurs.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.6
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• pp.625-632
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• 2012

The objective of this paper is to demonstrate the cathode channel flooding effects at different stoichiometries in proton exchange membrane (PEM) fuel cells by using visualization techniques. The phenomena of liquid water formation and removal caused by current variations were also examined experimentally. Tests were conducted at cathode stoichiometries of 1.5 and 2.0, and the anode stoichiometry was fixed at 1.5. It is found that at an air-side stoichiometry of 2.0, liquid water begins to form and the flooding occurs faster than at an air-side stoichiometry of 1.5. Also, when the air-side stoichiometry of 1.5 is maintained, the dry-out phenomena is observed in the dry-out area 7.8 A following the field of flooding. Thus, a stoichiometry of 1.5 produced better performance in terms of membrane electrode assembly (MEA) durability and hydrogen ion conductivity than did a stoichiometry of 2.0, in which dry-out occurs beyond 8A.