• 수도
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• v.23 no.5 s.80
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• pp.31-45
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• 1996

• Korean Journal of Animal Reproduction
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• v.17 no.4
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• pp.339-346
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• 1994

An understanding of the structure and function of mammalian spermatozoa requires the iso-lation of these components. In this study, frozen-thawed bovine spermatozoa were treated by physical treatments (vortexing, 26 gauge needle, strained 26 gauge needles and freezing-thawing) or chemical treatments (trypsin, dithiothreitol, sodium dodecylsulfate and $\beta$-mercaptoethanoJ) to yield free heads and tails. The most effective treatment was repeated pumping of sperm suspension through a strained 26 gauge needle conneted to a syringe. Spermatozoa by this treatment were mainly broken at the junction of the head and the tail, resulting in 90-100% yields. Also, sperm head surface did not modify during strained 26 gauge needle treatment when either spermatozoa or sperm heads were incubated in 250${\mu}\textrm{g}$/ml of FITC-UEA 1 for 1 h at room temperature to detect the modification of sperm surface components. Other physical treatments were less efficient for the breakdown of spermatozoa. The effects of chemical treatments on bovine spermatozoa are not noticeable. Dissected sperm heads and tails should be fractional leading to nearly pure components by sucrose gradient centrifugation at 1,000 rpm for 15 min. The result suggest that the established method may be useful for the biochemical study of spermatozoal components, and the understanding of oocyte activation mechanism either by spermatozoal components during fertilization or microinjection of isolated components.

• Food Engineering Progress
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• v.22 no.4
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• pp.344-352
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• 2018

The effects of chemical compositions (protein, lipid, and dietary fiber) on the physical properties of dried biji powders were investigated. The raw biji was freeze-dried (control) and hot-air dried (untreated). The untreated biji was further defatted and deproteinated. The prepared biji powders were analyzed for the proximate composition, total dietary fiber (TDF), water absorption index (WAI), water solubility index (WSI), swelling power, solubility (including the quantification of soluble carbohydrate and protein fractions), and final viscosity (using a rapid visco analyzer). Control and untreated biji powders exhibited the similar chemical compositions. The defatted biji possessed higher TDF, although its protein content did not significantly differ for control and untreated ones. The deproteinated biji consisted mainly of TDF. WAI and swelling power increased in the order: deproteinated > defatted > control > untreated biji powders. WSI and solubility increased in the order: control > untreated > defatted > deproteinated biji powders. The similar patterns were observed for soluble carbohydrate and protein fractions. The deproteinated biji revealed the highest viscosity over applied temperatures, while the untreated one was lowest. Overall results suggested that the physical properties of the dried biji powder were reduced by protein and fat, but enhanced by dietary fiber.

• Journal of Food Hygiene and Safety
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• v.34 no.1
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• pp.106-114
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• 2019

The effect of physical and chemical treatments to reduce staphylococcal phages was investigated. To determine impact of physical treatment on viability of phages, two staphylococcal phages (SAP84 and SAP89) were treated with multiple heat ($55^{\circ}C$ and $60^{\circ}C$) and pH (pH4, 7, 10) conditions. Viability of SAP 84 was dramatically reduced at 60C and SAP 89 was completely inactivated at 60C within 25 min. Overall, the two phages were stable under all the pH conditions tested except for the SAP 89 at pH 10. Treatments, a 10% FAS (Ferrous Ammonium Sulfate) solution and various density of ethanol and sodium hypochlorite were used to reduce the two phages. SAP 84 was unstable in 50% and 70% ethanol. However, SAP 84 and SAP 89 showed high tolerance after exposure to 100 ppm of sodium hypochlorite which is known as an effective sterilizer. As soon as the two phages were treated with 10% FAS, which is used as a virucidal agent, they were inactivated and did not form any plaque. The result of this study provides additional evidence that staphylococcal phages can be controlled by various physicochemical treatments.

• Conservation Science in Museum
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• v.3
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• pp.21-27
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• 2001

In National Central Museum, we recently preserved paper cultural assets, such as ancient maps, books and antique documents etc, to prepare "A Dynamic World of External Relations in Goryeo & Joseon Dynasty". The paper cultural assets generally react sensitively to their environments; temperature, humidity, light and physical force acting. Biological damages, which are caused by microbe, contraction, swelling and damage from insects occurred. Wrinkles on relics, which are made my physical force, stains on relics which are due to moisture, weakening of adhesive strength and damages from insects were found during the recent preservation handling. Therefore we are trying to find out any damage, which could be occurred in paper cultural assets and introduce brief emergency operation to prevent the damages and develop the preservation handling.

• Bulletin of Food Technology
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• v.10 no.3
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• pp.104-108
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• 1997

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.783-790
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• 2003

Tetranychus urticae Koch and Panonychus ulmi Koch were identified as quarantine pests in apple samples and were controlled soon after the commercial treatment of methyl bromide (MeBr) and with irradiation doses $(0.5{\sim}3kGy)$ after irradiation. The physical qualities of apples, such as rotting, withering, weight changes, hardness, and color, were apparently affected by MeBr. Furthermore, more than 2 kGy irradiation resulted from the lapse of storage time. Associated with the physical qualities of stored apples, irradiation and fumigation for quarantine purposes were more adequate after 40 days of storage at $0{\pm}1^{\circ}C\;(85{\pm}2%\;RH)$ immediately following harvest, rather than soon after harvest. Less than 1 kGy irradiation, based on its accumulated control effect on pests, can potentially be applied as a quarantine procedure without causing significant changes in the physical qualities of fresh apples, in contrast to MeBr.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.172-174
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• 2011

표면경도와 내마모특성을 가진 질화처리는 다양한 철강재료에 적용되고 있다. 플라즈마를 이용한 질화법은 다른 질화처리법에 비해 처리시간이 짧고 폐수 및 배기가스와 같은 오염물질의 발생이 거의 없어 친환경적이며 낮은 온도에서 처리가 가능하기 때문에 변형 및 금속학적 물성의 변화가 없는 것이 특징이다. 한편 DLC 처리법은 물리화학적 특성이 다이아몬드와 유사하면서도 저온 합성이 가능하고, 표면이 평활하다는 합성기술상의 장점을 가지고 있기 때문에 많은 분야에서의 응용이 연구되고 있는 재료이다. 특히 고경도, 고윤활성 등의 물리적, 화학적, 광학적 특성과 화학적 안정성과 신체적합성 등의 특성으로 인해 기계부품, 공구, 광학기기, 전자부품, 자동차부품과 의료용 기기분야 등에 적용하고 있다. 본 연구에서는 질화처리 및 DLC 처리를 한 챔버내에서 동시처리하여 그 특성을 평가하였다. 이와같이 얻어진 처리물을 Field Emission Scanning Electron Microscope를 이용하여 단면분석을 하였고, 시편의 경도는 나노인덴터로 측정하였다. ball-on-disk 방식의 마모시험기를 이용하여 내마모특성을 관찰하였으며, 접합력을 측정하기 위해 스크래치 테스트를 실시하였다.

• Nuclear Engineering and Technology
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• v.29 no.6
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• pp.60-64
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• 1997

핵연료의 가공공정에서 발생하는 스러지를 건식처리공정으로 회수 정제할 수 있는 건식처리 방법에 대하여 논의하고자 하였다. 건식처리방법은 수용액을 전혀 사용하지 알기 때문에 폐기물의 발생량이 습식처리방법에 비해 훨씬 줄어든다. 산화우라늄은 고온의 용융염중에서 염소개스에 의해 염소화반응을 통하여 우라늄염화물을 생성되게 되어 이들은 전기적으로 이동이 가능한 형태로 바뀌므로 전극에 선택적으로 전착될 수 있기 때문에 다른 금속이온과 분리할 수 있다. 본 보고서에서는 산화우라늄의 염소화공정, 전착공정에 대하여 기술하였고 전착된 산화물의 물리적 특성에 대하여 요약하였다.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.857-862
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• 2007

본 논문에서는 대형 화면의 tabletop display상에서 물리적인 감각을 통해 정보를 직관적으로 조작할 수 있는 스마트 퍽 시스템을 제시한다. 기존의 데스크 탑 PC 환경의 인터페이스는 물리적인 마우스와 디지털 정보의 공간적인 불일치가 생기고 마우스의 물리적인 움직임과 모니터 상 그래픽 커서의 이동을 맵핑하여 간접적으로 정보를 조작하므로, 사용자에게 직관적인 인터페이스를 제공해 주지 못하는 한계가 있다. 스마트 퍽은 물리적인 인터페이스 장치로써 tabletop display상의 디지털 정보를 직접 조작할 수 있고, 스마트 퍽을 끌거나 들어서 옮기거나 회전시키는 등의 물리적인 조작을 통해 사용자에게 디지털 정보와의 직관적인 인터페이스를 제공한다. 또한 대형 화면의 tabletop display는 여러 사용자가 함께 화면에 표시되는 정보를 공유하고 조작하는데 적합하다. 스마트 퍽 시스템은 인간의 아날로그적인 지각과 반응을 통한 물리적인 인터랙션과 가상의 디지털 정보와의 거리를 줄여주는 역할을 한다. 이 시스템은 PDP 기반의 tabletop display 장치와 스마트 퍽, 그리고 tabletop display상의 스마트 퍽의 위치를 추적하는 위치 추적 장치와 스마트 퍽의 입력을 전송 받아 정보를 처리하는 메인 PC로 구성된다. 마지막으로 스마트 퍽 시스템의 인터페이스를 적용한 몇 가지 예시를 보여주고자 한다.