Silicon Nanocrystals Synthesized from Silicon Tetrachloride Using Electron Beam Reduction Reaction

이돈성,강현석,고예슬,이병철,정현담 대한화학회 2015 Bulletin of the Korean Chemical Society Vol.36 No.3

Silicon nanocrystals (Si NCs) were synthesized by the electron beam reduction reaction (EBRR). Silicon tetrachloride (SiCl4), isopropyl alcohol (IPA), and toluene were used as the silicon source, radical scavenger, and solvent, respectively. Three types of sample were prepared: from a solution of SiCl4 and IPA under irradiation by an electron beam (e-beam) with energy, current, and dose of 1 MeV, 0.2 mA, and 300 kGy, respectively, and from the reactants (SiCl4 -only or SiCl4 + IPA) under no e-beam irradiation. New features in the ultraviolet–visible absorption and photoluminescence spectroscopies for the case of e-beam irradiation were attributed to the formation of the Si NCs, as confirmed by fast Fourier transform processed image in field-emission transmission electron microscopy analysis. The possibility of the formation of the Si NCs was also validated by the Gibbs free energy calculations of the proposed reaction mechanism for EBRR of the SiCl4 precursor.

한국 생유의 유당함량과 빙점(氷點)의 변화에 관한 연구

이돈성 한국낙농학회 1982 韓國酪農學會誌 Vol.4 No.3

This study was carried out to know the standard lactose contents and freezing point of raw milk produced in Korea. The results obtained were summarized as follows: 1. Lactose contents of raw milk was 4.737±0.297% and its range was 3.33∼5.31%, and free zing point, -0.555 ± 0.0228℃, -0.6510∼-0.5170℃. 2. Lactose contents of raw milk was not related significantly with freezing point which was due to the improper preservation of raw milk during summer. 3. Lactose contents had shown very narrow variation and there was no statistical difference in monthly variation lactose contents. 4. Monthly variation of freezing point was high and it was believed that the poor preservation of raw milk in summer was the major cause.

한국생유의 유당함량, pH와 적정산도(滴定酸度)의 변화에 관한 연구

이돈성 한국낙농학회 1982 韓國酪農學會誌 Vol.4 No.3

This study was carried out to investigate the monthly variation and their correlations among lactose contents, pH and titrable acidity of raw milk produced in Korea. The results obtained were summarized as follows; 1. Lactose contents of raw milk was 4.737±0.297 % and its range was 3.33∼5.31 %, pH,6.533 ±0.196, 5.80∼ 6.90, titrable acidity, 0.180 ±0.039% , 0.106∼0.299%. 2. Correlation coefficient between pH and titrable acidity was -0.9035 and its regression equation was Y=-4.5254X + 7.3459. 3. Monthly variation of pH and titrable acidity was very significant but that of lactose contents was not.

Effect of electron beam irradiation on the capacity fading of hydride-terminated silicon nanocrystal based anode materials for lithium ion batteries

이돈성,최영화,정현담 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.53 No.-

The selection of binder is extremely important in silicon based lithium-ion batteries (LIBs). Polyvinylidene fluoride (PVDF) has been used as a commercial binder. However, it does not accommodate a large change in volume during cell cycling. In this study, we report on the rediscovery of the use of PVDF without additional synthetic processes or further treatment. By utilizing simple and short e-beam irradiation, hydride-terminated silicon nanocrystals (H-Si NCs) and PVDF can be chemically cross-linked each other, and shows an improved cell performance. This result demonstrates a high potential of the ebeam irradiation process on Si-based anode materials in LIBs.

Effects of surface functionalization and polymerization on anode characteristics of plasma-synthesized silicon nanocrystal active materials for lithium ion battery anode

이돈성,이동명,유승완,김정형,정현담 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

We investigate the effects of surface functionalization and polymerization on the anode characteristics ofplasma synthesized-silicon nanocrystal (Si NC) based active materials for anode of lithium ion batteries(LIBs). Surface functionalized Si NCs were synthesized by adopting capping molecule to the hydride-terminated Si NCs (H–Si NCs) via hydrosilylation, and polymerization with a silane agent to form artificialsolid electrolyte interphase (SEI) layer capped Si NCs, which show a dramatic decrease in SEI layerresistance (Rsei). This result demonstrates the high potential of surface functionalized Si NCs as activematerials in anode of LIBs.

Distinct Band Gap Tunability of Zinc Oxysulfide (ZnOS) Thin Films Synthesized from Thioacetate-Capped ZnO Nanocrystals

이돈성,정현담 한국진공학회 2014 Applied Science and Convergence Technology Vol.23 No.6

ZnO matrix. ZnO nanocrystals (NCs) with a diameter of 10 nm were synthesized by forcedhydrolysis in an organic solvent. As-synthesized ZnO NCs aggregated with each other dueto the high surface energy. As acetic acid (AA) was added into the milky suspension ofthe aggregated ZnO NCs, transparent solution of well dispersed ZnO NCs formed. FinallyZnOS NCs were formed by adding thioacetic acid (TAA) to the transparent solution. Theeffect of recrystallization on the structural, optical and electrical properties of the ZnOS NCswere studied. The results of UV-vis absorption confirmed the band gap tunability causedby increasing the curing temperature of ZnOS thin films. This may have originated fromthe larger effective size due to the recrystallization of zinc sulfide (ZnS). From XRD resultwe identified that ZnOS thin films have a zinc blende crystal structure of ZnS without wurtziteZnO structure. This is probably due to the small amount of ZnO phases. These assertionswere verified through EDS of FE-SEM, XPS and EDS mapping of HR-TEM results; weclearly proved that ZnOS were comprised of ZnS and ZnO phases.

Organo-Functionalization of Silicon Nanocrystals Synthesized by Inductively Coupled Plasma Chemical Vapor Deposition

이돈성,Dong-Hoe Choe,유승완,김정형,정현담 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.5

Octadecyl-terminated silicon nanocrystals (ODE-Si NCs) are obtained via a surface-initiated thermal hydrosilylation reaction on hydride-terminated Si NCs (HSi NCs). Pristine Si NCs were synthesized at the gram scale by using inductively coupled plasma chemical vapor deposition (ICP-CVD). The HSi NCs were produced through a chemical etching process with hydrofluoric acid (HF), ethanol (EtOH), and distilled water (d-H2O). The results obtained from X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) indicate that the synthesized Si NCs obtained via ICP-CVD have diamond cubic-structured silicon with a grain size of 10 nm and a densely packed Si NC array consisting of individual NCs. Organo-functionalized Si NCs, i.e., ODE-Si NCs, are well soluble in organic solvent whereas pristine Si NCs synthesized through ICP-CVD are not. The surface chemistry of the ODE-Si NCs was confirmed via Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H-NMR), and field emission transmission electron microscopy (FE-TEM). Thereby, these newly synthesized and scalable organo-functionalized Si NCs are applicable as raw materials for practical use in devices by tuning the surface chemistry with various capping molecules.

한국산생유(韓國産生乳)의 성분에 관한 연구 : 경기도 평택지방을 중심으로 In Pyung-taek in Kyong-ki area

김현욱,이돈성,김정환,김형균,장영호,권일경 한국낙농학회 1983 韓國酪農學會誌 Vol.5 No.3

이 硏究는 경기도 평택지방에서 생산된 생유시료 3000여점의 乳組成을 알아 봄으로서, 한국산 생유의 대표적 성분함량을 알기 위한 노력의 일환으로 실시되었으며 그 결과는 다음과 같다. 1. 生乳試料의 平均乳組成은 脂肪 3.84%, 蛋白質 3.41%, 乳糖 4.69%, 無脂乳固形分 8.81%, 總乳固形分 12.65%였다. 2. 月別平均乳組成을 볼 때 脂肪과 總乳固形分含量은 여름철이 다른 계절에 비해 낮았고, 그 외 成分은 큰 變化가 없었다. 3. 總乳固形分은 脂肪(r=0.896) 및 無脂乳固形分(r=0.731)과, 無脂乳固形分은 蛋白質 (r=0.764) 및 乳糖(r=0.500)과 높은 상관계수를 나타내었다. This study aimed to provide the partial knowledge for the raw milk composition in Korea by analyzing 3,000 odd raw milk sample produced in Pyong-taek in Kyong-ki area. The results obtained were summarized as follow. 1. The average contents of raw milk components were fat 3.84%, protein 3.41%, lactose 4.69%, SNF 8.81%, and TS 12.65%, respectively. 2. Referring to the monthly variation in average raw milk compositions, fat and TS contents in summer were higher than other seasons, and other components had a little variation. 3. TS and fat (r=0.896), TS and SNF (r=0.731), SNF and protein (r=0.764), and SNF and Lactose (r=0.500) were shown in high correlation coefficients.

Streptococcus faecalis bacteriophage ATCC 29200 의 특성과 생존에 관한 연구

김현욱,이돈성,장영호,김정환 한국낙농학회 1985 韓國酪農學會誌 Vol.7 No.2

This study was to provide the general knowledge of Streptococcus faecalis bacteriophage ATCC 29200. The results obtained were summarized as follows: 1. The latent period and the average burst size of phage ATCC 29200 were 60 min and. 50 pfu, 5 strains of S. feaecalis strains tested were susceptible to phage ATCC 29200, in the presence of Ca ions, and phage ATCC 29200 produced clear plaques of 1-1.5 mm in diameter. The phage required calcium ion for the lysis of the host cell, and Ca^(++) and Mg^(++) in the media helped the host cell attack. 2. Phage ATCC 29200 had a large, elongated head and long, non-contractile tail, its head and tail size were 110 × 40 ㎚ and 140 × 10 ㎚. Further detailes of the phage molphology needed more study. 3. Phage ATCC 29200 were unstable below pH 5.5, inactivated by the additon of sodium pyrophpsphate, D-glucosamine and sodium hyperchloride and by heating above 65℃. 4. By using proper heat treatment of media, addition of inhibition material for phage adsorption, and good sanitization of the plant, the effective inactivation or prevention systems against the phage could be developed in the industries. 이 硏究는 Streptococcus faecalis bacteriophage ATCC 29200의 特性을 硏究하여 phage의 汚染防止 및 抑制에 必要한 基礎知識을 얻고저 실시되었으며, 그 結果는 다음과 같다. 1. Phage ATCC 29200의 潛伏期는 60분, 平均放出數는 50pfu였고 直徑 1-1.5㎜의 透明한 溶菌盤을 만들었다. 18種의 S. faecalis 종5種이 Ca^(++)존재하에 phage ATCC 29200에 감수성을 보였고, 增加시 칼슘이온을 요구하며, Mg^(++)은 phage의 吸着을 촉진하였으나 Mn^(++), Co^(++), Hg^(++)는 phage를 不活性化 하는 것으로 믿어진다. 2. Phage ATCC 29200은 크고 긴 頭部와 길고 非收縮性의 꼬리를 같고 있었으며 頭部의 크기는 110×40㎚, 꼬리의 크기는 140×10㎚였으며, 기타 구조는 硏究중에 있다. 3. Phage ATCC 29200은 pH 5.5 이하에서는 不安定하며 Sodium pyrophosphate, D-glucosamine 및 Sodium hyperchlorite 등의 添加로 活性化되었으며 65℃이상의 熱處理로 대부분 死滅되었다. 4. 培養시 사용되는 培地 및 醱酵器具의 올바른 熱處理, 吸着 妨害物質의 添加, 공장내부의 위생유지 등에 의한 phage의 效率的인 抑制 및 예방방법이 고안될 수 있다고 믿어진다.

한국산 Holstein 우유의 성분에 관한 연구

김현욱,이돈성,장영호,김희수 한국낙농학회 1985 韓國酪農學會誌 Vol.7 No.4

本 硏究는 경기도 지역에서 생산된 生乳 試料 1918點의 乳組成을 分析함으로서 韓國産 Holstein 生乳의 性質을 알기 위하여 실시한 것으로 그 결과는 다음과 같다. 1. 生乳試料의 平均乳組成은 乳脂肪 3.694%, 乳蛋白質 3.384%, 乳糖 4.713%, 無脂固形分 8.797%, 總固形分 12.491%, pH 6.621, 適定酸度 0.177%, 氷點 -0.5462。H로 나타났다. 2. 乳脂肪, 乳蛋白質, 無脂固形分과 總固形分含量은 月別 變化가 有意性을 나타내고 있으나 다른 成分은 큰 變化의 有意性을 나타내지 않았다. 3. 無脂固形分과 總固形分은 一般 乳成分과 높은 相關 關係를 가지며 適定酸度와 pH(r=-0.9146) 및 氷點(r=-0.6918)은 높은 負의 相關 關係를 나타내며 氷點과 pH(r=0.6212)도 높은 相關 關係를 나타낸다. 4. 無脂固形分(Y)과 乳蛋白質의 回歸方程式은 Y=0.906X+0.204이며, 總固形分(Y)과 乳脂肪, pH(Y)와 適定酸度 및 氷點(Y)과 乳脂肪의 回歸方程式은 各各 Y=1.259 X-0.938, Y=5.049 X-0.713과 Y=0.003X+3.5093으로 나타나며 고도의 유의성을 갖는 것으로 확인되었다. This study was carried out to elucidate the chemical composition of the raw Holstein cow milk through analyzing 1918 raw milk samples collected in Kyong-Ki area. The results obtained have been summarized as follow: 1. The average values of raw milk composition were found to be fat, 3.694%; protein, 3.384%; lactose, 4.713%; solid-not-fat(SNF), 8.797%; total solid, 12.491%; pH 6.621; titratable acidity, 0.177%; freezing point, -0.5462˚H, respectively. 2. Fat, protein, SNF and total solid contents evidenced significant monthly variations while other components didn't show much variations. 3. Between SNF and other components except freezing point, and between total solid and fat, protein and lactose, high correlation coefficients were evident. Between titratable acidity and pH(r=-0.9146), and freezing point (r=-0.6918), high negative correlation ceofficients were appeared and high correlation value was also evident between freezing point and pH (r=0.6212). 4. The linear regression equation between SNF(Y) and protein, between total solid(Y) and fat, between pH(Y) and titratable acidity, and between freezing point(Y) and fat were Y=0.906X+0.204, Y=1.259X-0.938, Y=5.049X-0.713 and Y=0.003X+3.5093, respectively which gave high significance.