• Journal of Electrical Engineering and Technology
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• 제12권5호
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• pp.2007-2013
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• 2017

In order to give hydrophobic surface properties on carbon steel, the fluorinated amorphous carbon films were prepared by using linear 2.45GHz microwave PECVD device. Two different process approaches have been tested. One is direct deposition of a-C:H:F films using admixture of $Ar/CH_4/CF_4$ working gases and the other is surface treatment using $CF_4$ plasma after deposition of a-C:H film with $Ar/CH_4$ binary gas system. $Ar/CF_4$ plasma treated surface with high $CF_4$ gas ratio shows best hydrophobicity and durability of hydrophobicity. Nanometer scale surface roughness seems one of the most important factors for hydrophobicity within our experimental conditions. The properties of a-C:H:F films and $CF_4$ plasma treated a-C:H films were investigated in terms of surface roughness, hardness, microstructure, chemical bonding, atomic bonding structure between carbon and fluorine, adhesion and water contact angle by using atomic force microscopy (AFM), nano-indentation, Raman analysis and X-ray photoelectron spectroscopy (XPS).

• Bulletin of the Korean Chemical Society
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• 제31권10호
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• pp.2923-2928
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• 2010

This study examined the synthesis of the crystal structure of bis(2,2'-bipyridine)nitrato zinc (II) nitrate, $[Zn(bipy)_2(NO_3)]^+NO_3^-$ using a microwave treatment at 300 W and 60 Hz for the application to dye-sensitized solar cells. The simulated complex structure of the complex was optimized with the density functional theory calculations for the UV-vis spectrum of the ground state using Gaussian 03 at the B3LYP/LANL2DZ level. The structure of the acquired complex was expected a penta-coordination with four nitrogen atoms of bipyridine and the oxygen bond of the $NO_3^-$ ion. The reflectance UV-vis absorption spectra exhibited two absorptions (L-L transfers) that were assigned to the transfers from the ligand ($\sigma$, $\pi$) of $NO_3$ to the ligand ($\sigma^*$, $\pi^*$) of pyridine at around 200 - 350 nm, and from the non-bonding orbital (n) of O in $NO_3$ to the p-orbital of pyridine at around 450 - 550 nm, respectively. The photoelectric efficiency was approximately 0.397% in the dye-sensitized solar cells with the nanometer-sized $TiO_2$ at an open-circuit voltage (Voc) of 0.39 V, a short-circuit current density (Jsc) of $1.79\;mA/cm^2$, and an incident light intensity of $100\;mW/cm^2$.

• 농업과학연구
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• 제49권2호
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• pp.249-257
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• 2022

The present study investigates the effects of different inclusion levels of a microwave-dried black soldier fly (Hermetia illucens) larvae meal (HILM) on the carcass characteristics, breast meat quality, and fatty acid profiles of leg meat in broiler chickens. A total of 150 male broilers were randomly assigned to three dietary treatment groups (10 replicates·treatment^-1 and 5 birds·replicate^-1). HILM was included at increasing levels (0, 2, and 4%; CON, 2HILM, and 4HILM, respectively) in diets formulated for three feeding phases: starter (1 - 7 d), grower (7 - 21 d), and finisher (21 - 35 d). One bird per replicate was slaughtered at d 35; the carcasses and organs were weighed, and breast and leg meats were excised for a meat analysis. A linear decrease (p < 0.01) was observed for live and carcass weights for the whole period of the experiment, with no difference between the CON and 2HILM groups. Broilers fed HILM showed no significant differences in meat quality parameters, except for an increase in yellowness (b^*) in the 2HILM and 4HILM groups compared to the CON group (p < 0.01). With an increase in the HILM inclusion level, the proportion of saturated fatty acids (SFAs) such as lauric, myristic, stearic, arachidic, and heneicosylic acids showed a linear increase (p < 0.01); however, total SFA, monounsaturated fatty acid, and polyunsaturated fatty acid did not differ among the dietary treatments. Thus, microwave-dried HILM can be considered as a possible alternative ingredient to soybean meal in broiler diets up to a 2% inclusion level.

• Korean Journal of Radiology
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• 제21권5호
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• pp.572-581
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• 2020

Objective: To evaluate the safety, feasibility, and efficacy of microwave ablation (MWA) for the treatment of primary hyperparathyroidism (PHPT). Materials and Methods: This study enrolled 67 PHPT patients (22 men, 45 women; mean age, 56.0 ± 16.3 years; range, 18-83 years) from January 2015 to December 2018. The laboratory data, including the serum intact parathyroid hormone (iPTH), calcium, phosphorus, and alkaline phosphatase (ALP) levels, were evaluated before MWA and again 2 hours, 1 day, 7 days, 1 month, 3 months, 6 months, 12 months, 18 months, and 24 months after. Results: Complete ablation was achieved with all 72 hyperplastic parathyroid glands found on the 67 patients enrolled, 64 of whom were treated in one session and 3 were treated over two sessions. The technical success rate was 100%. The median follow-up time was 13.6 months (range, 10.0-31.1 months). The clinical success rate was 89.4%. The volume reduction rate was 79.4% at 6 months. Compared to pre-MWA, the serum iPTH, calcium, phosphorus, and ALP levels had significantly improved 6 months post-MWA (iPTH, 157.3 pg/mL vs. 39.2 pg/mL; calcium, 2.75 ± 0.25 mmol/L vs. 2.34 ± 0.15 mmol/L; phosphorus, 0.86 ± 0.20 mmol/L vs. 1.12 ± 0.22 mmol/L; ALP, 79 U/L vs. 54 U/L, respectively; all, p < 0.01). Hoarseness was a major complication in 4 patients (6.0%), but it improved spontaneously within 2-3 months. Conclusion: MWA is safe, feasible, and effective for the treatment of PHPT.

• Applied Biological Chemistry
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• 제34권3호
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• pp.225-230
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• 1991

깍뚜기 제조시 절임액에의 KCI 첨가, microwave 열처리 및 인산염, nitrate, 구연산염 등 혼합염의 첨가가 저장성 향상에 어떤 효과가 있는지 밝히고져 이들 첨가나 처리를 단독 또는 병행하여 깍두기 발효중 pH, 총산도, 환원당의 변화를 비교하였다. 그 결과 절임시 KCI의 첨가와 발효중 염혼합물의 첨가는 $25^{\circ}C$에서 발효와 저장을 하였을 때 신맛이 지나치게 나타나는 pH4.0에 도달하는 시간이 대조구에 비하여 약 6.4배의 연장점이 밝혀졌으며, $25^{\circ}C$에서 발효시킨 뒤(약 pH4.4) 염혼합물을 넣고 $4^{\circ}C$에서 저장하였을 경우 같은 방법으로 처리한 뒤 $25^{\circ}C$에서 저장한 경우보다 약 8배 이상의 저장기간이 향상됨이 밝혀졌다. 한편 총산도의 변화는 염혼합물의 첨가나 열처리가 대조구보다 높게 나타났으며 절임시 KCI 첨가와 microwave 열처리만의 병용은 pH 변화 억제에 뚜렷한 영향이 없었다. 발효중 환원당 함량의 변화는 $4^{\circ}C$나 $25^{\circ}C$ 저장의 경우 절임시 KCI 첨가나 절임 깍뚜기 무우의 microwave 열처리에 있어서는 대조구와 별 차이가 나타나지 않았으나 혼합염을 첨가하여 저장하였을 때는 대조구에 비하여 완만한 감소현상이 뚜렷하였다.

• 열처리공학회지
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• 제21권5호
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• pp.235-243
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• 2008

Ni-C composite films were prepared using a combination of microwave plasma CVD and ion beam sputtering deposition working in a codeposition way. The structure of these films was characterized by energy-dispersive X-ray diffraction (EDXRD), transmission electron microscopy (TEM) and Raman spectroscopy. It was found that a nickel carbide phase, $Ni_3C$ (hcp), formed as very fine crystallites over a wide temperature range when Ni-C films were deposited at low $CH_4$ flow rates. The thermal stability of this nonequilibrium carbide $Ni_3C$ was also studied. As a result, the $Ni_3C$ carbide was found to decompose into nickel and graphite at around $400^{\circ}C$. With high $CH_4$ flow rates (> 0.2 sccm), the structure of the Ni-C films became amorphous. The formation behavior of the carbide and amorphous Ni-C phases are discussed in relation to the electrical resistivity of the films.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.189-190
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• 2005

본 논문에서는 탄소나노튜브를 성장시키기 전 과정인 전처리시 촉매 층에 인가되는 마이크로웨이브 파워에 따른 탄소나노튜브의 성장 및 특성 변화를 관찰하였다. 촉매층으로 사용되는 Ni층과 adhesion층으로 사용되는 Ti층은 마그네트론 스퍼터링 방식으로 증착하였고, 탄소나노튜브 성장에는 마이크로웨이브 플라즈마 화학기상 증착기를 사용하였다 탄소나노튜브의 성장특성은 평면과 단면 SEM image를 통하여 관찰하였으며, Raman spectrometer 분석을 통하여 성장된 탄소나노튜브의 구조적 특성을 알아보았다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권2호
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• pp.737-742
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• 2012

To evaluate efficacy of microwave ablation in a primary clinical study, sixty patients (44 men, 16 women; mean age 53 years) with 96, 1-8 cm (mean $3.20{\pm}0.17$ cm) liver cancers were treated with 2,450-MHz internally cooled-shaft antenna. Complete ablation (CA) and local tumor progression (LTP) rates as well as complications were determined. CA rates in small (< 3.0 cm), intermediate (3.1-5.0 cm) and large (5.1-8.0 cm) liver cancers were 96.4% (54/56), 92.3% (24/26) and 78.6% (11/14), respectively. During a mean follow-up period of $17.17{\pm}6.52$ months, LTP occurred in five (5.21%) treated cases. There was no significant difference in the CA and LTP rates between the HCC and liver metastasis patient subgroups (P<0.05). Microwave ablation provides a reliable, efficient, and safe technique to perform hepatic tumor ablation.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.158-166
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• 2004

원자력 발전소에서 발생하는 방사성 폐기물인 이온교환수지, 제올라이트, 활성탄 및 슬러지에 포함된 핵종 분석을 위한 최적의 산분해 조건을 확립하였다. 방사성 폐기물의 분해에는 혼합산을 이용한 밀폐형 극초단파 산분해법을 사용하였으며, 제안한 방법에 따른 산분해 후의 용액은 맑고 색이 없는 투명한 상태임을 확인할 수 있었다. 또한, 산분해 과정을 거친 각각의 용액 시료는 ICP-AES와 AAS를 사용하여 분석하였고, 모의 방사성 폐기물에 첨가한 5종의 금속 원소들은 94% 이상의 높은 회수율을 보여주었다. 화학적 특성을 고려하여 제안된 산분해 조건은 핵종 분석을 위한 효과적인 전처리 방법으로써, 향후 원전의 유형별 방사성 폐기물에 대해 보편적으로 적용될 수 있을 것으로 판단된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권2호
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• pp.65-71
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• 2007

토양복원의 기술로 마이크로파를 이용할 시 휘발성물질((PAH)s 등)) 및 준휘발성((PCB)s 등) 물질 등을 처리하는데 효과적인 것으로 알려져 있다. 본 연구에서는 휘발성 물질인 BTEX를 마이크로파를 이용하여 수분변화 및 전력변화에 따른 제거특성을 연구하였다. 10%, 20%, 30%, 50%의 함수율 변화에 따른 BTEX 제거율은 20%일 때가 제거율이 가장 높음을 제거상수를 통해 도출할 수 있었으며, 전력의 변화에 따른 BTEX 제거율 및 제거율에 도달하는 시간은 비슷한 것으로 나타났다. 각각 다른 함수율이 마이크로파 처리 시 한계함수율에 도달하는 시간을 측정한 결과, 한계함수율에 도달하는 시간은 함수율이 10%, 20%, 30%일 때는 2 kW와 4 kW는 큰 차이가 없음을 알 수 있었고, 함수율이 50%일 경우는 한계함수율에 도달하는 시간이 4kW가 더 빠른 것으로 나타났다. 수분함수율에 따른 최적전력을 도출하면 수분함량이 $10{\sim}30%$ 시 2 kW가 경제적으로 나타났으며, 함수율이 50% 일 경우는 전력이 4 kW일 때 경제적인 것으로 나타났다.