• Journal of Korean Dental Science
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• 제9권1호
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• pp.19-27
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• 2016

Purpose: Laser treatment has become a popular method in implant dentistry, and lasers have been used for the decontamination of implant surfaces when treating peri-implantitis. This study was performed to evaluate the effects of an Erbium-doped:Yttrium-Aluminum-Garnet (Er:YAG) laser with different settings on machined (MA), sand-blasted and acid-etched (SA), and resorbable blast media (RBM) titanium surfaces using scanning electron microscopy and confocal microscopy. Materials and Methods: Four MA, four SA, and four RBM discs were either irradiated at 40 mJ/20 Hz, 90 mJ/20 Hz, or 40 mJ/25 Hz for 2 minutes. The specimens were evaluated with scanning electron microscopy and confocal microscopy. Result: The untreated MA surface demonstrated uniform roughness with circumferential machining marks, and depressions were observed after laser treatment. The untreated SA surface demonstrated a rough surface with sharp spikes and deep pits, and the laser produced noticeable changes on the SA titanium surfaces with melting and fusion. The untreated RBM surface demonstrated a rough surface with irregular indentation, and treatment with the laser produced changes on the RBM titanium surfaces. The Er:YAG laser produced significant changes on the roughness parameters, including arithmetic mean height of the surface (Sa) and maximum height of the surface (Sz), of the MA and SA surfaces. However, the Er:YAG laser did not produce notable changes on the roughness parameters, such as Sa and Sz, of the RBM surfaces. Conclusion: This study evaluated the effects of an Er:YAG laser on MA, SA, and RBM titanium discs using confocal microscopy and scanning electron microscopy. Treatment with the laser produced significant changes in the roughness of MA and SA surfaces, but the roughness parameters of the RBM discs were not significantly changed. Further research is needed to evaluate the efficiency of the Er:YAG laser in removing the contaminants, adhering bacteria, and the effects of treatment on cellular attachment, proliferation, and differentiation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.147-150
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• 2002

The electron field emission properties of amorphous carbon (a-C) films deposited using a RF magnetron sputtering system have been improved by introducing a simple method of argon plasma treatment at room temperature. Surface morphologies and structural properties of the a-C films were investigated by scanning electron microscopy and Raman spectroscope, respectively. Structural properties and surface morphologies of the a-C films were changed by argon plasma treatment. The emission properties improved with the plasma treatment.

• 한국전기전자재료학회논문지
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• 제23권1호
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• pp.10-13
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• 2010

The plasma processing technologies of thin film deposition and surface treatment technique have been applied to many industrial fields. This study is purposed Large-area uniformity and surface treatment on the stainless substrate. We treat surface of stainless by $CF_4$ plasma. $CF_4$ plasma is generated by using SPM(Scanning plasma method)which is kind a of CVD. Generally, SPM has been used for uniform surface treatment using a crossed electromagnetic field. The optimum discharge condition has been studied for the gas pressure, the magnetic flux density and the distance between substrate and electrodes. In result, contact angle is increased by surface treatment using $CF_4$ Plasma. Therefore we expect that SPM to control contact angle is applied to many industries.

• 폴리머
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• 제31권1호
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• pp.31-36
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• 2007

플라스마 표면처리는 전체적인 물성은 유지하고 표면의 특성만을 변화시킨다고 전해지고 있다. 이번 연구에서는 플라스마 처리에 의해 높은 발수성을 나타내는 나일론 6 섬유로의 개질을 시도하였다. 발수성을 나타내는 나일론 섬유는 가스 종류, 처리시간, 인가 파워를 변수로 하여 RF 진공 플라스마 시스템에서 처리되었다. 플라스마 처리된 섬유의 표면을 scanning electron microscopy(SEM)과 atomic force microscopy(AFM)으로 모폴로지 변화를 살펴보았으며, 기계적 특성과 고분자 고유의 특성을 인장강도와 Differential scanning calorimetry(DSC), thermo-gravimetric analysis (TGA)로 각각 분석하였다. 또한 나일론 섬유의 발수성 평가는 물방울 흡수시간으로 테스트를 실시하였다. 이러한 결과들은 플라스마 표면처리로 인해서 나일론 섬유의 발수성이 향상됨을 나타내었다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1989년도 춘계학술대회
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• pp.9-12
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• 1989

A preliminary study has been conducted to demonstrate the effect of laser heat treatment on Ni Ti alloy dental arch wires ($0.016"\;{\times}\;0.022"$ and $0.018"\;{\times}\;0.026"$, rectangular shape). Changes in mechanical and thermal properties and surface morphologies are investigated by using optical and scanning electron microscope (SEM), energy dispersive x-ray microprobe analysis(EDX), differential scanning calorimeter (DSC), and micro hardness tester. The results indicate that the laser can affect the thermal equilibrium state of the localized surface. Titanium rich surface film is formed by the laser treatment. The surface film and rapidly resolidified underlying structures show better chemical resistance than the matrix material. Phase transition temperatures which are related to shape recovery temperatures are changed after laser treatment. Hardness of resolidified area and heat affected zone are lower than before treatment.

• 보건의료기술평가
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• 제6권2호
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• pp.156-161
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• 2018

Objectives: To evaluate results and workloads of the horizon scanning of the emerging health technology since 2014 to 2016. Methods: In order to analyze the results of the emerging health technology, we identified the number of research procedure between 2014 and 2016. The sixteen findings were calculated annual workload by person, and categorized by medical phase, classification of disease, and healthcare technology. Results: An average of 5.67 personnel were involved over three years, assessment of each emerging healthcare technology was performed for each person of identifying 54 cases, filtering 2.4 cases, prioritizing 0.9 cases were performed. According to the mapping by healthcare technologies, nine medical devices (56.3%), six drugs (37.5%), and one material of the medical treatment (6.3%) were assessed. Among sixteen findings, fifteen cases were health technologies for treatment and only one case for diagnosis. Conclusion: Future plans of the horizon scanning of the emerging health technology is required appropriate manpower in charge each target number of assessment. And a legal basis should be provided for policy reflection rate. Furthermore, an evaluation criteria and procedures should be transparent to avoid a conflict of interest.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.265-270
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• 1993

Ammonia and/or sulphur dioxide treated and untreated wheat leaf sheaths were compared for cell wall digestion by incubation with rumen liquor for 24 and 48 hours. Scanning electron microscope (SEM) was used to study the relative rate and extent of cell wall digestion. Treated wheat straw leaf sheaths were distorted, with more distortion observed in ammonia and sulphur dioxide combined treatment than any other treatment. Rumen liquor digestion for 24 hours of untreated leaf sheath showed disrupted phloem, partially ruptured parenchyma and vascular tissues and further partially distorted inner bundle sheaths and vascular bundle after 48 hours incubation. Sulphurated leaf sheaths showed extensive degraded parenchyma and sclerenchyma material in 24 hours incubation, however, all tissues were irregulary shaped in 48 hours incubation. In ammoniation, epidermal cell walls and small vascular bundles began to disintegrate by 24 hours incubation, extensively changed structure and degraded epidermal tissue by 48 hours incubation. Combination treatment of leaf sheaths degraded all cell walls of parenchyma, phloem and vascular bundle by 24 hours incubation, however, structures only of inner bundles sheath with extended land, sclerenchyma and cutinized epidermal cell walls remained.

• 한국전기전자재료학회논문지
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• 제17권12호
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• pp.1332-1336
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• 2004

Amorphous carbon (a-C) films have been deposited on Si(100) substrate using RF magnetron system in order to investigate the electron field emission properties. The a-C films were treated by $N_2$ gas plasma at room temperature. Surface morphologices and structural properties of the a-C films before and after $N_2$ plasma treatment were observed by scanning electron microscopy and Raman spectroscope, respectively. Structural properties and surface morphology of the a-C films were changed by $N_2$ plasma treatment. The emission properties can be improved by the plasma treatment according to the contents of nitrogen on the a-C films which is varied by plasma treatment time. Before the plasma treatment, the a-C films are found to have a threshold field of 14 V/$\mu$m, but the a-C film treated by $N_2$ plasma for 30 min exhibit threshold field as low as 6.5 V/$\mu$m.

• 한국축산식품학회지
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• 제33권3호
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• pp.317-324
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• 2013

Radio-frequency driven atmospheric pressure plasma using argon gas was studied in the inactivation of Campylobacter jejuni in order to investigate its applicability. First, the inactivation study was conducted on an agar surface. C. jejuni NCTC11168 was reduced by more than 7 Log CFU after an 88 s treatment. Another strain, ATCC49943, was studied; however, the inactivation was less efficient, with a 5 Log CFU reduction after a 2 min treatment. Then, chicken breast ham was studied at the $10^6$ CFU inoculation level. The inactivation efficiency was much lower for both strains compared to that on the agar plates. C. jejuni NCTC11168 and ATCC49943 were reduced by 3 Log CFU after a 6 min treatment and by 1.5 Log CFU after a 10 min treatment, respectively. The scanning electron microscopy analysis indicated that C. jejuni cells were deformed or transformed into coccoid form under the plasma treatment. During the plasma treatment, the temperature of the samples did not rise above $43^{\circ}C$, suggesting that heat did not contribute to the inactivation. Meanwhile, water activity significantly decreased after a 10 min treatment (p<0.05). This study conveyed that radio-frequency atmospheric pressure plasma can effectively inactivate C. jejuni with strain-specific variation.

• 열처리공학회지
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• 제4권3호
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• pp.21-30
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• 1991

Microstructural analysis was conducted to observe the effect of aging treatments in a Cr-Mn austenitic stainless steel containing nitrogen, and the amount, size, shape and distribution of precipitates were investigated. It was found that on water quenching from $1000^{\circ}C$ after holding 3 h at that temperature, the steel contained no precipitates observable by optical microscopy. Precipitation of phases begins at places most favorable for the formation of nuclei-in the boundaries of grains and twins. Precipitates were studied in detail by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Chemical compositions of precipitates were examined by the use of scanning transmission electron microscopy (STEM) together with an energy dispersive X-ray (EDX) microanalysis. Also chromium depletion adjacent to grain boundary precipitates was investigated by the use of Auger electron spectroscopy (AES) for a direct examination of the fracture surface chemistry.