• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.9
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• pp.686-689
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• 2013

The carbon nanowall (CNW) is a carbon-based nanomaterials and it was constructed with vertical structure graphenes and it has the highest surface density among carbon-based nanostructures. In this study, we have checked the growth properties of CNW according to the substrate angle. Microwave plasma enhanced chemical vapor deposition (PECVD) system was used to grow CNW on Si substrate with methane ($CH_4$) and hydrogen ($H_2$) gases. And, we have changed the substrate angle from $0^{\circ}$ to $90^{\circ}$ in steps of $30^{\circ}$. The planar and vertical conditions of the grown CNWs according to the substrate angle were characterized by a field emission scanning electron microscopy (FE-SEM) and energy dispersive spectroscopy (EDS). In case of the growth angle increases, our experimental results showed that the length of the CNW was shortened and the content of carbon component was decreased.

• Food Science of Animal Resources
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• v.20 no.4
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• pp.264-271
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• 2000

정육 대체물질의 첨가에 따른 효과를 살피기위해 건조 소 혈장 단백질을 단계별로 높이면서 제조한 비엔나 소시지의 물성적 특성 드을 경시적으로 고찰 비교하였다. 수율은 방냉후 축정된 것으로 81.60~84.88% 범위이며 대조구와 D-2, D-3간의유의적인 차이를 보였다. (P<0.05). 조직의 부분적인 연화 정도는 대조구에 비해 비교구에서 소 혈장 단백질의 첨가수준이 높은 시럼구에서 높았고 열 매체에 의한 영향은 boiled>microwave>fried의 순이 었다. 겔강도와 경도는 대조구와 비교구 사이, 수직 측정과 수평 측정 사이, 저장기간에 따라 유의적인 차이를 볼 수 있었다.(P<0.05), 전단 강도는 수직측정보다는 수평측정이 높은 수치를 보이고 initial에서 대조구와 비교구 사이 차이가 적게 나타나나 40일 저장한 것에서는 차이 값이 높았다. 전단 경도에 있어서는 initial 에 비해 10일 , 40일 에는 감소함을 보이나 수칙측정과 수평측정간 차이를 보였다 L 값은 시험구간과 저장기간에 의해서도 안정함을 보이며 a값은 대조구에 비해 비교구에서 감소함을 보이나 10일 40일 저장된 것에서 증가함을 보이고, b값은 시험구간 사이 비슷한 수준이나 저장기간에 따라서는 감소를 보였다. 기호성 평가에서 색상, 풍미, 조직감은 시험 제품 사이에 차이를 보이고 저장기간에 의해서는 약간의 감소를 보이며 천제적인 수용도는 대조구가 가장 높은 점수였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.291-291
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• 2010

Electron-beam lithography (EBL) process is a versatile tool for a fabrication of nanostructures, nano-gap electrodes or molecular arrays and its application to nano-device. However, it is not appropriate for the fabrication of sub-5 nm features and high-aspect-ratio nanostructures due to the limitation of EBL resolution. In this study, the precision assembly and alignment of DNA molecule was demonstrated using sub-5 nm nanostructures formed by a combination of conventional electron-beam lithography (EBL) and plasma ashing processes. The ma-N2401 (EBL-negative tone resist) nanostructures were patterned by EBL process at a dose of $200\;{\mu}C/cm2$ with 25 kV and then were ashed by a chemical dry etcher at microwave (${\mu}W$) power of 50 W. We confirmed that this method was useful for sub-5 nm patterning of high-aspect-ratio nanostructures. In addition, we also utilized the surface-patterning technique to create the molecular pattern comprised 3-(aminopropyl) triethoxysilane (APS) as adhesion layer and octadecyltrichlorosilane (OTS) as passivation layer. DNA-templated gold nanoparticle chain was attached only on the sub-5 nm APS region defined by the amine groups, but not on surface of the OTS region. We were able to obtain DNA molecules aligned selectively on a SiO2/Si substrate using atomic force microscopy (AFM).

• Proceedings of the Materials Research Society of Korea Conference
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• 2009.05a
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• pp.55.2-55.2
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• 2009

A polymer electrolyte membrane (PEM) fuel cell has been getting large interest as a typical issue in useful applications. The PEMFC is composed of a membrane, catalyst and the bipolar plate. SnOx:F films on SUS316 stainless steel were prepared as a function of substrate with using electron cyclotron resonance-metal organic chemical vapor deposition (ECR-MOCVD) in order to achieve the corrosion-resistant and low contact resistance bipolar plates for PEM fuel cells. The SnOx:F films coated on SUS316 substrate at surface plasma treatment for excellent stability, before/after heat treatment for good crystalline structure and microwave power for were characterized by X-ray diffraction (XRD), auger electron microscopy (AES) and field emission-scanning electron microscopy (FE-SEM). The SnOx:F film coated on SUS316 substrate with various process parameters were able to observe optimum interfacial contact resistance (ICR) and corrosion resistance. It can be concluded that fluorine-doping content plays an important function in electrical property and characteristic of corrosion-protective film.

• Proceedings of the Membrane Society of Korea Conference
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• 1997.04b
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• pp.13-16
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• 1997

The permeation, solution and diffusion of simple gases ($He, H_2, O_2, N_2$ and CH$_4$) and condensible vapers($CO_2, SO_2, C_2H_4$ and $C_3H_8$), and the mixed gases ($O_2/N_2$ mixtures and $CO_2/CH_4$ mixtures) through composite membrane was studied. Composit membranes were made by deposition of aromatic fluorocarbons onto polymer substrams of porous Celgard in a microwave discharge. In the both cases of simple gases and condensible vapors, as the kinetic molecular diameter of the permeant molecules increased, the permeability decreased. However, when the kinetic molecular dimemr are similar, the condensible vapors showed higher permeabilities than that of permanent gases. The vapor solubility increased with increasing critical temperature of the vapors. However, in the case of propane, despite its high critical temperature, it showed lower solubility than other vapors. The vapor diffusivity decreased with increasing kinetic diameter of the molecule. Compared to conventional polymers, the plasma polymers showed much lower values for vapor diffusivities. The pressure of the permeant did not affect the permeability. The permeability was also not affected by the composition in cases of mixed gases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.10
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• pp.1195-1204
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• 2017

This study was designed to determine the effects of three cooking methods, boiling, microwave, and steaming, on elemental compositions of green pumpkin, zucchini, and sweet and ripened pumpkin. The cooking methods were carried out at 3, 5, and 10 min. The samples were then dried, crushed, and decomposed by microwave-assisted digestion method. Macro elements were analyzed by Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES), whereas ICP-Mass Spectrometer (ICP-MS) was used for micro elements determination. From the results, macro elements were present in the order of K, P, Ca, Mg, S, Fe, Zn, and Na in all analyzed pumpkins. Among micro elements, Mn, Cu, Rb, and Ba, were present at high levels. For the effects of cooking methods, boiling significantly reduced the concentrations of elements. Cooking time affected concentrations of elements in the same manner with large differences between elemental contents in samples cooked for 5 and 10 min. Regarding micro elements contents, both effects were not significant. Similar elemental compositions with different concentration levels in all pumpkin types were observed. Green pumpkin and ripened pumpkin showed high retention rates of inorganic components upon steaming, and zucchini and sweet pumpkin showed high retention rates upon microwave cooking. Conclusively, cooking method and time affect amounts of residual inorganic ingredients in pumpkin.

• Mass Spectrometry Letters
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• v.3 no.2
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• pp.58-61
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• 2012

A method based on flow injection-isotope dilution-cold vapor-inductively coupled plasma mass spectrometry (FI-IDCV-ICP/MS) has been applied to determine trace level of mercury in fly ash. $^{200}Hg$ isotopic spike was added to 0.25 g of BCR176R fly ash and then decomposed by microwave digestion procedure with acid mixture A (8 mL $HNO_3$ + 2 mL HCl + 2 mL HF) and acid mixture B (8 mL $HNO_3$ + 2 mL $HClO_4$ + 2 mL HF) for applying IDMS. Mercury cold vapor was generated by using reductant solution of 0.2% (w/w) $NaBH_4$ and 0.05% (w/w) NaOH. The measurements of n($^{200}Hg$)/n($^{202}Hg$) isotope ratio was made using a quadrupole ICP/MS system. The accuracy in this method was verified by the analysis of certified reference material (CRM) of fly ash (BCR 176R). The indicative value of Hg in BCR 176R fly ash was $1.60{\pm}0.23$ mg/kg (k = 2). The determined values of Hg in BCR 176R fly ash by the method of FI-CV-ID-ICP/MS described in this paper were $1.60{\pm}0.24$ mg/kg (k = 3.18) and the analysis results were in well agreement with the indicative value within the range of uncertainty.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.440-446
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• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

• Journal of radiological science and technology
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• v.27 no.2
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• pp.45-50
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• 2004

Synthesis diamond films have been deposited on the molybdenum substrates using an microwave plasma enhanced chemical vapor deposition method. The effects of deposition time, surface morphology, infrared transmittance and Raman scattering have been studied. Diamond deposited on molybdenum substrate for 100 hours by MW plasma CVD from $CH_4-H_2-O_2$ gas mixture had good crystallity with $100[{\mu}m]$ thickness needed for radiation detector. Diamond radiation detector of M-I-M type was made and the current of radiation detector was increased by increasing X-ray dose.

• Journal of the Korean Vacuum Society
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• v.7 no.3
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• pp.267-267
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• 1998

The fluorine doped silicon oxide (SiOF) intermetal dielectric (IMD) films have been of interest due to their lower dielectric constant and compatibility with existing process tools. However instability issues related to bond and increasing dielectric constant to water absorption when the SiOF films was exposured to atmospheric ambient. Therefore, the purpose of this research is to study the effect of post oxygen plasma treatment on the resistance of moisture absorption and reliability of SiOF film. Improvement of moisture absorption resistance of SiOF film is due to the forming of thin SiO₂layer at the SiOF film surface. It is thought that the main effect of the improvement of moisture absorption resistance was densification of the top layer and reduction in the number of Si-F bonds that tend to associate with OH bonds. However, the dielectric constant was increased when plasma treatment time is above 5 min. In this study, therefore, it is thought that the proper plasma treatment time is 3 min when plasma treatment condition is 700 W of microwave power, 3 mTorr of process pressure and 300℃ of substrate temperature.