• Design & Manufacturing
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• 제16권1호
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• pp.50-54
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• 2022

Coverglass of electronic equipments is thinner and slimmer, so the glass must have good bending strength. In these days, the polishing edge of glass is used by solid tool like grinding wheel. But solid tool leave micro crack or edge chipping in edge of glass. MR polishing is an optimal method by polishing edge of glass. MR polishing is used MR fluid that is a liquid tool. MR polishing doesn't leave tool path or residual stress, micro crack and edge chipping unlike grinding wheel polishing. In this paper, the results of grinding and MR polishing were compared and analyzed to improve bending strength by minimizing edge chipping of cover glass. It was derived that the depth and size of cracks have a significant influence on the bending strength of the glass edge. The edges of the glass using MR grinding were analyzed to have a better surface and higher bending strength than the glass using abrasive wheel grinding. It was confirmed that MR polishing had an effect on strength improvement by effectively removing cracks in the specimen.

• Bulletin of the Korean Chemical Society
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• 제32권2호
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• pp.583-589
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• 2011

Fluorescence correlation spectroscopy (FCS) is a sophisticated and an accurate analytical technique used to study the diffusion of molecules in a solution at the single-molecule level. FCS is strongly affected by many factors such as the stability of the excitation power, photochemical processes, mismatch between the refractive indices, and variations in the cover glass thickness. We have studied FCS near the surface of a cover glass by using rhodamine 123 as a fluorescent probe and have observed that the surface has a strong influence on the measurements. The temporal autocorrelation of FCS decays with two characteristic times when the confocal detection volume is positioned near the surface of the cover glass. As the position of the detection volume is moved away from the surface, the FCS autocorrelation becomes one-component decaying; the characteristic time of the decay is the same as the faster-decaying component in the FCS autocorrelation near the surface. This observation suggests that the faster component can be attributed to the free diffusion of the probe molecules in the solution, while the slow component has its origin from the interaction between the probe molecules and the surface. We have characterized the surface contribution to the FCS measurements near the surface by changing the position of the detection volume relative to the surface. The influence of the surface on the diffusion of the probe molecules was monitored by changing the chemical properties of the surface. The surface contribution to the temporal autocorrelation of the FCS strongly depends on the chemical nature of the surface. The hydrophobicity of the surface is a major factor determining the surface influence on the free diffusion of the probe molecules near the surface.

• 한국응용곤충학회지
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• 제8권
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• pp.25-28
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• 1969

콩 탄저병균(G. glycines)의 침입전 부착기의 구조와 그 형성조건을 알기 위하여 몇 가지 접촉제 커바 그리스, 셀로판, 비닐 그리고 유지론 사용하여 본 시험을 착수하였다. G. glycines의 부착기형성에는 접촉제 커바 그라스를 덮어 Water Agar에 처리한 구에는 12시간만에 $67.7\% 부착기가 형성된 반면 대조구에는 전연 형성되지 않았다. 부착기 형성에 있어서 공시한 4가지 접촉제의 효과는 비닐이 가장 좋았고 다음이 새로판 커바그라스 및 유지의 순이었다. 온도 습도 시간이 콩잎상에서 G. glycines의 부착기형성에 미치는 효과는 본 병원균의 호적온도 및 온도범위와 같이 $25^{\circ}-30^{\circ}C,\;R.H.\; 75-100\%$이었다. 그리고 36시간 처리구에서 가장 많은 부착기가 형성되었으며, 온도 $35^{\circ}C$이상 습도 $75\%$이상, 및 5시간 처리구에서는 아주 적은 수의 부착기가 형성되었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.129.1-129.1
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• 2005

• JSTS:Journal of Semiconductor Technology and Science
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• 제1권4호
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• pp.232-238
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• 2001

A new DNA purification chip is proposed and fabricated for the sample preparation of Nucleic Acid (NA) probe assay. The proposed DNA purification chip is fabricated using photosensitive glass substrate and polydimethylsiloxane (PDMS) cover fixture. We have successfully captured and eluted the DNA using the fabricated photosensitive glass chip. The fabricated DNA purification chip showed a binding capacity of $15ng/\textrm{cm}^2$and a minimum extractable input concentration of $100copies/200\muL$. The proposed DNA purification chip can be applied for low-cost, disposable sample preparation of NA probe assays.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.274-280
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• 2008

To investigate the flexural behavior of real size RC beams strengthened with glass fiber sheets, 9 strengthened beams of real size are experimented and the results are compared with those of existing experimental studies. Experiments are considered glass fiber sheets, the number of fiber sheets, and the existence of U-wrap. By the results of experiments, the failure behavior and crack types of real size RC beams are almost equal to those of the small size RC beams, and the debonding and not the concrete cover delamination are occurred. It can be found from the load-deflection curves that as the number of fiber sheets is increased, the ductility of real size RC beam is more decreased than that of the small size RC beam. For the strengthening method with glass fiber sheets of the real size RC beams, it can be confirmed that the finding a solution to the bonding problem is required

• 한국세라믹학회지
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• 제52권1호
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• pp.23-27
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• 2015

Recently, the use of ion-exchange strengthened glass has increased sharply, as it is now used as the cover glass for smart phone devices. Therefore, many researchers are focusing on methods that can be used to strengthen ion-exchange glass. However, research on how the improved strength can be maintained under thermal environment of device manufacturing is still insufficient. We tested the degradation of the characteristics of ion-exchange soda-lime glass samples, including their surface compressive stress characteristics, the depth of the ion-exchange layer (DOL), flexural strength, hardness, and modulus of rupture (MOR) values. Degradation of the characteristics of the ion-exchange glass samples occurred when they were heat-treated at a temperature that exceeded $350^{\circ}C$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.268-269
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• 2008

Charging of spacecraft occurs in plasma and radiation environment. Especially, we focused on an accident caused by internal charging in a glass material that was used as the cover plate of solar panel array, and tried to measure the charge distribution in glass materials under electron beam irradiation by using a PEA (Pulsed Electro-Acoustic method) system. In the case of a quartz glass (pure $SiO_2$), no charge accumulation was observed either during or after the electron beam irradiation. On the contrary, positive charge accumulation was observed in glass samples containing metal-oxide components. It is found that the polarity of the observed charges depends on the contents of the impurities. To identify which impurity dominates the polarity of the accumulated charge, we measured charge distributions in several glass materials containing various metal-oxide components and calculated the trap energy depths from the charge decay characteristics of all glass samples.

• 원예과학기술지
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• 제35권1호
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.

• Journal of Advanced Marine Engineering and Technology
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• 제33권7호
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• pp.994-1002
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• 2009

In this paper, effect of air gap thickness between absorber plate and glass cover on top heat loss of a closed loop oscillating heat pipe (CLOHP) solar collector was investigated. The CLOHP, which is made of copper with outer diameter of 3.2mm and inner diameter of 2.0mm, comprises 8 turns with heating, adiabatic and cooling section. The heating section of the heat pipe was attached to absorber plate which heated by solar simulator simulated by halogen lamps. The cooling section of the heat pipe was inserted into collector's cooling section that made of transparent acrylic. Temperatures of absorber plate, glass cover, and ambient air measured by K-type thermocouple and were recorded by MV2000-Yokogawa recorder. Top heat loss coefficients and top heat loss of the collector corresponding to some cases of air gap thickness were determined. The result of experiment shows the optimal air gap thickness for minimum top heat loss of this solar collector.