• 한국식생활문화학회지
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• 제16권1호
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• pp.13-19
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• 2001

Since 1982, female agricultural workers are populous than male in Korea. Previous study was suggested that female workers are more sensitive to the agricultural medicine poisoning than male. This study was conducted with the aim of evaluating the impact on plasma components and nutrient intakes in female agricultural workers by the use of pesticides. Data were obtained from 44 females residing in Wonjoo, Kangwon-do area. Analysis for the general characteristics, nutrient intakes, and plasma components of the subjects were performed by physical examination, 24-hour recall method and venous blood sampling. They were divided into 3 groups according to the degree of the pesticide use: 8 in none(Non-expose group), 14 in low(<4/yr)(Low-expose group), and 22 in high$({\geq}4/yr)$(High-expose group). The results are summarized as follows. Serum glucose, SGOT, SGPT, triglyceride, HDL-cholesterol did not correlated with pesticide use and were not different among the groups. But serum total cholesterol was higher in pesticide use group. With increasing the number of pesticide use times, leukocyte count was tended to increased. Eighty two percent of the subjects were hemoglobin less than or equal to 12g/dl. Hematocrit, MCV, MCH, MCHC, serum Fe, Serum ferritin belonged to normal range and did not correlated with pesticide use. Intake of energy, Fe, vitamin $B_2$ were lower than RDA. Fe, K, and vitamin A intake were higher in don't use group than the other groups. There are not many differences according to using the pesticide in anthropometric measurements, nutrient intakes, and blood components, except for serum total cholesterol level and some nutrients intake. But these results suggest the need the systemic researches about the effects the pesticide using on nutritional status in Korean agricultural workers.

• 대한금속재료학회지
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• 제49권11호
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• pp.845-852
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• 2011

The Spark Plasma Sintering(SPS) method offers a means of fabricating a sintered-body having high density without grain growth through short sintering time and a one-step process. A titanium compact having high density and purity was fabricated by the SPS process. It can be used to fabricate a Ti sputtering target with controlled parameters such as sintering temperature, heating rate, and pressure to establish the optimized processing conditions. The compact/target(?) has a diameter of ${\Phi}150{\times}6.35mm$. The density, purity, phase transformation, and microstructure of the Ti compact were analyzed by Archimedes, ICP, XRD and FE-SEM. A Ti thin-film fabricated on a $Si/SiO_2$ substrate by a sputtering device (SRN-100) was analyzed by XRD, TEM, and SIMS. Density and grain size were up to 99% and below $40{\mu}m$, respectively. The specific resistivity of the optimized Ti target was $8.63{\times}10^{-6}{\Omega}{\cdot}cm$.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.234-235
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• 2006

In this study, the plasma sprayed $Al_2O_3$ and $Y_2O_3$ coatings have been investigated for applications of microelectronic components. The plasma sprayed coatings had a well-defined splatted lamellae microstructure, intersplat pores and a higher amount of microcracks within the splats. The plasma sprayed $Y_2O_3$ coating had a relatively lower hardness of 300-400Hv, compared to 650-800Hv for $Al_2O_3$ coating, and would be readily damaged by mechanical attacks such as erosion, wear and friction. For a reactive ion etching against F-containing plasmas, however, the $Y_2O_3$ coating had a much higher resistance than the $Al_2O_3$ coating because of the reduced erosion rate of by-products.

• 한국환경과학회지
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• 제33권5호
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• pp.323-332
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• 2024

Circulating hydroponic cultivation has the advantage of reducing soil and water pollution problems caused by discharge of fertilizer components because the nutrient solution is reused. However, cyclic hydroponic cultivation has a low biological buffering capacity and can cause outbreaks of infectious root pathogens. Therefore, it is necessary to develop technologies or disinfection systems to control them. This study used dielectric barrier discharge plasma, which generates various persistent oxidants, to treat Fusarium oxysporum f. sp., a pathogen that causes wilt disease. Batch and intermittent continuous inactivation experiments were conducted, and the results showed that the total residual oxidant was persistent in intermittent plasma treatment at intervals of 2-3 days, and F. oxysporum was treated efficiently. Intermittent plasma treatment did not inhibit the growth of tomatoes.

• Applied Science and Convergence Technology
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• 제27권5호
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• pp.100-104
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• 2018

Herein, we present the behavior of plasma-doped graphene upon high-temperature vacuum annealing. An ammonia plasma-treated graphene sample underwent vacuum annealing for 1 h at temperatures ranging from 100 to $500^{\circ}C$. According to Raman analysis, the structural healing of the plasma-treated sample is more pronounced at elevated annealing temperatures. The crystallite size of the plasma-treated sample increases from 13.87 to 29.15 nm after vacuum annealing. In addition, the doping level by plasma treatment reaches $2.2{\times}10^{12}cm^{-2}$ and maintains a value of $1.6{\times}10^{12}cm^{-2}$, even after annealing at $500^{\circ}C$, indicating high doping stability. A relatively large decrease in the pyrrolic bonding components is observed by X-ray photoelectron spectroscopy as compared to other configurations, such as pyridinic and amino bindings, after the annealing. This study indicates that high-vacuum annealing at elevated temperatures provides a method for the structural reorganization of plasma-treated graphene without a subsequent decrease in doping level.

• Nutritional Sciences
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• 제6권1호
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• pp.12-19
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• 2003

The measurement of the total antioxidant capacity (TAC) of human plasma has been widely applied in nutritional science, for example to evaluate the antioxidant contribution of dietary components and to study, although indirectly, the bioavailability of dietary antioxidants. Several methods have been proposed for the measurement of TAC, most of them based on the ability of plasma to withstand the oxidative damage induced by aqueous radicals. Although plasma contains both hydrophilic and lipophilic antioxidants that interact through extensive cross-talk in most of the methods employed for the TAC measurement, the hydrophilic antioxidants such as ascorbic acid, uric acid, and protein thiols mainly contribute to the total antioxidant plasma capacity (almost 70%) while lipophilic antioxidants embedded in the lipoproteins (carotenoids, a-tocopherol, ubiquino1-10) participate only in a negligible amount (less than 5%). The present paper reviews the analytical methods used to assess the TAC and in particular focuses on new approaches that are capable of distinguishing the antioxidant capacity of both the aqueous and lipid compartments of plasma. The general principle of the method as well as some in vitro and ex vivo applications will be discussed within the text.

• Elastomers and Composites
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• 제39권1호
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• pp.12-22
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• 2004

라디오 주파수(13.56 MHz) 무전극 종형 플라즈마 반응기를 이용하여 천연고무 가교체의 표면을 클로로디플루오로메탄으로 처리하였다. FT-적외선 분광분석으로 표면개질 정도를 정성적으로 조사하였다. 플라즈마 처리표면의 마찰힘은 플라즈마 처리시간 증가에 따라 감소하였다. 고무표면에 에틸렌글리콜과 물을 떨어뜨려 접촉각을 측정한 결과 플라즈마 처리에 따라 감소하는 것으로 미루어 플라즈마 개질에 따라 표면극성이 증가하는 것을 확인하였다. 유리판 표면을 동일조건으로 플라즈마 처리한 경우는 극성의 감소만이 확인되었다. 표면자유에너지의 London 비극성 및 극성요소를 계산하는데 있어서 기하평균법과 조화평균법이 유용한 것으로 확인되었다. 평균방법에 관계없이 플라즈마 처리시간이 증가함에 따라 표면자유에너지는 증가하였다 그러나 조화평균법으로 계산된 자유에너지가 기하평균법으로 계산된 값에 비해 상대적으로 높았다. 플라즈마 표면개질은 마찰의 계면, 히스테리시스, 점성요소들에 영향을 미침으로써 마찰계수를 변화시키는 것으로 나타났다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.664-667
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• 1997

For higher component density per chip, it is necessary to identify and control the semiconductor manufacturing process more stringently. Recently, neural networks have been identified as one of the most promising techniques for modeling and control of complicated processes such as plasma etching process. Since wafer states after each run using identical recipe may differ from each other, conventional neural network models utilizing input factors only cannot represent the actual state of process and equipment. In this paper, in addition to the input factors of the recipe, real-time tool data are utilized for modeling of 64M DRAM s-poly plasma etching process to reflect the actual state of process and equipment. For real-time tool data, we collect optical emission spectroscopy (OES) data. Through principal component analysis (PCA), we extract principal components from entire OES data. And then these principal components are included to input parameters of neural network model. Finally neural network model is trained using feed forward error back propagation (FFEBP) algorithm. As a results, simulation results exhibit good wafer state prediction capability after plasma etching process.

• Journal of Plant Biotechnology
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• 제43권4호
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• pp.405-410
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• 2016

Auxins are essential in plant growth and development. The auxin-stimulated elongation of plant cells has been explained by the "acid-growth theory", which was proposed forty years ago. According to this theory, the auxin activates plasma membrane $H^+-ATPase$ to induce proton extrusion into the apoplast, promoting cell expansion through the activation of cell wall-loosening proteins such as expansins. Even though accepted as the classical theory of auxin-induced cell growth for decades, the major signaling components comprising this model were unknown, until publication of recent reports. The major gap in the acid growth theory is the signaling mechanism by which auxin activates the plasma membrane $H^+-ATPase$. Recent genetic, molecular, and biochemical approaches reveal that several auxin-related molecules, such as TIR1/AFB AUX/IAA coreceptors and SMALL AUXIN UP RNA (SAUR), serve as important components of the acid-growth model, phosphorylating and subsequently activating the plasma membrane $H^+-ATPase$. These researches reestablish the four-decade-old theory by providing us the detailed signaling mechanism of auxininduced cell growth. In this review, we discuss the recent research progress in auxin-induced cell elongation, and a set of possible future works based on the reestablished acid-growth model.

• 한국재료학회지
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• 제31권7호
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• pp.397-402
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• 2021

In this study, binderless-WC, WC-6 wt%Co, WC-6wt% 1 and 2.5 B₄C materials are fabricated by spark plasma sintering process (SPS process). Each fabricated WC material is almost completely dense, with a relative density up to 99.5 % after the simultaneous application of pressure of 60 MPa. The WC added Co and Co-B₄C materials resulted in crystalline growth. The WC with HCP crystal structure has respective interfacial energy (basal facet direction: 1.07 ~ 1.34 J·m^-2, prismatic direction: 1.43 ~ 3.02 J·m^-2) that depends on the grain growth direction. It is confirmed that the continuous grain growth, biased by the basal facet, which has relatively low energy, is promoted at the WC/Co interface. As abnormal grain growth takes place, the grain size increases more than twice from 0.37 to 0.8 um. It is found through analysis that the hardness property also greatly decreases from about 2661.4 to 1721.4 kg/mm², along with the grain growth.