NGHIÊN CỨU PHƯƠNG ÁN GIẢNG DẠY KỸ NĂNG NGHE ỨNG DỤNG PHIM TRUYỀN HÌNH ‘GIA ĐÌNH LÀ SỐ 1’ (Đối tượng sinh viên HQ học tiếng Việt trung cấp)

Lee Jee-sun,Nguyễn Thị Thu Hà 한국베트남학회 2019 베트남연구 Vol.17 No.1

N₂/ CH₄가스비에 따른 Hydrogenated Amorphous Carbon Nitride 박막의 특성

장홍규(H. K. Jang),김근식(G. S. Kim),황보상우(S. W. Whangbo),이연승(Y. S. Lee),황정남(C. N. Whang),유영조(Y. Z. Yoo),김효근(H. G. Kim) 한국진공학회(ASCT) 1998 Applied Science and Convergence Technology Vol.7 No.3

DC saddle-field-plasma-enhanced chemical-vapor deposition(PECVD) 장치를 이용하여 상온에서 p-type Si (100) 기판위에 hydrogenated amorphous carbon nitride [a-C:H(N)]박막을 증착하였다. 원료가스인 CH₄과 N₂의 전체압력은 90 mTorr로 고정하고 N₂/CH₄비를 0에서 4까지 변화하면서 제작한 a-C:H(N) 박막의 미세 구조의 변화를 연구하였다. 진공조의 도달 진공도는 1×10^(-6) Torr이고, 본 실험시 CH₄+N₂가스의 유량은 5 sc㎝으로 고정하고 배기량을 조절하여 진공조의 가스 압력을 90 mTorr로 고정하였으며 기판에 200 V의 직류 bias 전압을 인가하였다. α-step과 X-ray photoelectron spectroscopy(XPS)를 이용한 분석결과 N₂/CH₄비가 0에서 0.5로 증가함에 따라 박막 두께는 4840 Å에서 2600 Å으로 급격히 감소하였으며, 박막내의 탄소에 대한 질소함유량(N/C비)는 N₂/CH₄비가 4일때 최대 0.25로 증가하는 것을 확인하였다. 또한 XPS 스펙트럼의 fitting 결과 N₂/CH₄비가 증가할수록 CN결합이 증가하였다. Fourier Transformation Infrared (FT-IR) 분석결과 N₂/CH₄비가 증가함에 따라 박막내의 C-H 결합은 감소하고, N-H, C≡N 결합은 증가하였다. Optical bandgap 측정 결 과 N₂/CH₄비가 0에서 4로 증가함에 따라 a-C:H(N)박막의 bandgap 에너지는 2.53 eV에서 2.3 eV로 감소하는 것을 확인하였다. Hydrogenated amorphous carbon nitride[a-C:H(N)] films were deposited on p-type Si(100) at room temperature with substrate bias voltage of 200 V by DC saddle-field plasma-enhanced chemical vapor deposition. Effects of the ratio of N₂to CH₄(N₂/CH₄), in the range of 0 and 4 on such properties as optical properties, microstucture, relative fraction of nitrogen and carbon, etc. of the films have been investigated. The thickness of the a-C:H(N) film was abruptly decreased with the addition of nitrogen, but at N₂/CH₄> 0.5, the thickness of the film gradually decreased with the increase of the N₂/CH₄. The ratio of N to C(N/C) of the films was saturated at 0.25 with the increase of N₂/CH₄. N-H, C≡N bonds of the films increased but C-H bond decreased with the increase of N₂/CH₄. Optical band gap energy of the film decreased from 2.53 eV deposited with pure methane to 2.3 eV at the ratio of N₂/CH₄=4.

Interannual variation in summer N₂O concentration in the hypoxic region of the northern Gulf of Mexico, 1985-2007

Kim, I.-N.,Lee, K.,Bange, H. W.,Macdonald, A. M. Copernicus GmbH 2013 Biogeosciences Vol.10 No.11

<P><p><strong>Abstract.</strong> Microbial nitrous oxide (N₂O) production in the ocean is enhanced under low-oxygen (O₂) conditions. This is especially important in the context of increasing hypoxia (i.e., oceanic zones with extremely reduced O₂ concentrations). Here, we present a study on the interannual variation in summertime nitrous oxide (N₂O) concentrations in the bottom waters of the northern Gulf of Mexico (nGOM), which is well-known as the site of the second largest seasonally occurring hypoxic zone worldwide. To this end we developed a simple model that computes bottom-water N₂O concentrations with a tri-linear ΔN₂O/O₂ relationship based on water-column O₂ concentrations, derived from summer (July) Texas-Louisiana shelf-wide hydrographic data between 1985 and 2007. &amp;Delta;N₂O (i.e., excess N₂O) was computed including nitrification and denitrification as the major microbial production and consumption pathways of N₂O. The mean modeled bottom-water N₂O concentration for July in the nGOM was 14.5 ± 2.3 nmol L⁻¹ (min: 11.0 ± 4.5 nmol L⁻¹ in 2000 and max: 20.6 ± 11.3 nmol L⁻¹ in 2002). The mean bottom-water N₂O concentrations were significantly correlated with the areal extent of hypoxia in the nGOM. Our modeling analysis indicates that the nGOM is a persistent summer source of N₂O, and nitrification is dominating N₂O production in this region. Based on the ongoing increase in the areal extent of hypoxia in the nGOM, we conclude that N₂O production (and its subsequent emissions) from this environmentally stressed region will probably continue to increase into the future.</p> </P>

쥐의 근육 및 간장 콜레스테롤 수준에 미치는 사료 중 n-3 / n-6 지방산 , PUFA / SFA 및 MUFA / SFA 비율의 반응표면 분석

박병성(B . S . Park),고병대(B . D . Ko),이영철(Y . C . Rhee),황보종(J . Howang - Bo),성기승(K . S . Seong),이남형(N . H . Lee) 한국영양사료학회 1995 韓國營養飼料學會誌 Vol.19 No.5

Green synthesized multiple fluorescent nitrogen-doped carbon quantum dots as an efficient label-free optical nanoprobe for <i>in vivo</i> live-cell imaging

Atchudan, Raji,Edison, Thomas Nesakumar Jebakumar Immanuel,Perumal, Suguna,Clament Sagaya Selvam, N.,Lee, Yong Rok Elsevier 2019 Journal of photochemistry and photobiology Chemist Vol.372 No.-

<P><B>Abstract</B></P> <P>In this work, nitrogen-doped carbon quantum dots (N-CQDs) have been synthesized successfully by a simple hydrothermal method and demonstrated its application for multicolor imaging in <I>Caenorhabditis elegans</I> (<I>C. elegans</I>) as an <I>in vivo</I> model. The synthesized N-CQDs were characterized by various physicochemical techniques such as XRD, Raman spectroscopy, ATR-FTIR spectroscopy, XPS, HRTEM, UV–vis spectroscopy, and fluorescence spectroscopy. The synthesized N-CQDs exhibited a strong fluorescence due to the uniform size distribution with nitrogen-containing and oxygen-containing functional groups onto the surface of N-CQDs which induce the excellent dispersibility in aqueous media. The N-CQDs has an excitation-dependent fluorescence behavior and the strongest fluorescence appeared at 411 nm (emission peak position) under the excitation of 340 nm. Also, the N-CQDs displayed a high quantum yield (QY) of 12.5. The fluorescence behaviour of the aqueous N-CQDs suspension retains for a long time up to 1 year. The prolonging fluorescent N-CQDs was utilized as a staining agent for bioimaging and toxicity of N-CQDs on <I>C. elegans</I> that was conducted by killing assay. <I>In-vivo</I> studies suggested that the N-CQDs displayed excellent biocompatibility and successfully used for high-contrast imaging of N-CQDs in living and dead <I>C. elegans</I>. Based on the strongest fluorescence along with excellent aqueous dispersibility and biocompatibility, the green synthesized N-CQDs would be an ideal candidate for many biological applications.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A strongest multiple fluorescent N-CQDs were synthesized from the <I>P. acidus</I> fruits. </LI> <LI> Synthesized N-CQDs showed low-toxic and were employed for <I>in vivo</I> live-cell imaging. </LI> <LI> The N-CQDs were uniformly stained within the body of the nematodes (<I>C. elegans</I>). </LI> <LI> The live-cell imaging result reveals the usage of N-CQDs in drug delivery. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effect of controlled O₂ impurities on N₂ afterglows of RF discharges

Kang, N.,Lee, M.,Ricard, A.,Oh, S.g. Elsevier 2012 Current Applied Physics Vol.12 No.6

A RF capacitive flowing discharge and post-discharge are experimentally studied in N<SUB>2</SUB> gas and N<SUB>2</SUB>-(10<SUP>-4</SUP>-10<SUP>-2</SUP>)O<SUB>2</SUB> gas mixtures by using the optical emission spectroscopy at a pressure of 8 Torr, a flow rate of 1 slm and a transmitted RF power of 100 W. In these conditions the flowing discharge is distinguished by early and late afterglow. It is shown that the early afterglow is very sensitive to small quantity of O<SUB>2</SUB>. The band emissions from N<SUB>2</SUB><SUP>+</SUP>(B) and N<SUB>2</SUB>(B,υ') decreased sharply in the early afterglow when O<SUB>2</SUB> is introduced before the plasma. By using simple gas kinetics for pseudo-stationary conditions in the afterglows, N<SUB>2</SUB><SUP>+</SUP>+O<SUB>2</SUB> charge transfer and N<SUB>2</SUB>(a') quenching by O<SUB>2</SUB> play key roles in the afterglow. The charge transfers and quenching reactions are amplified when O-atoms are produced in the plasma. It is also observed that the O-atoms are produced in the early afterglow when O<SUB>2</SUB> is introduced after the plasma.

Direct analysis of site-specific N-glycopeptides of serological proteins in dried blood spot samples

Choi, N. Y.,Hwang, H.,Ji, E. S.,Park, G. W.,Lee, J. Y.,Lee, H. K.,Kim, J. Y.,Yoo, J. S. Springer Science + Business Media 2017 Analytical and Bioanalytical Chemistry Vol.409 No.21

<P>Dried blood spot (DBS) samples have a number of advantages, especially with respect to ease of collection, transportation, and storage and to reduce biohazard risk. N-glycosylation is a major post-translational modification of proteins in human blood that is related to a variety of biological functions, including metastasis, cell-cell interactions, inflammation, and immunization. Here, we directly analyzed tryptic N-glycopeptides from glycoproteins in DBS samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) without centrifugation of blood samples, depletion of major proteins, desalting of tryptic peptides, and enrichment of N-glycopeptides. Using this simple method, we identified a total of 41 site-specific N-glycopeptides from 16 glycoproteins in the DBS samples, from immunoglobulin gamma 1 (IgG-1, 10 mg/mL) down to complement component C7 (50 mu g/mL). Of these, 32 N-glycopeptides from 14 glycoproteins were consistently quantified over 180 days stored at room temperature. The major abundant glycoproteins in the DBS samples were IgG-1 and IgG-2, which contain nine asialo-fucosylated complex types of 16 different N-glycopeptide isoforms. Sialo-non-fucosylated complex types were primarily detected in the other glycoproteins such as alpha-1-acid glycoprotein 1, 2, alpha-1-antitypsin, alpha-2-macroglobulin, haptoglobin, hemopexin, Ig alpha 1, 2 chain C region, kininogen-1, prothrombin, and serotransferrin. We first report the characterization of site-specific N-glycoproteins in DBS samples by LC-MS/MS with minimal sample preparation.</P>

말라리아박멸을 위한 조사연구 : 1. 말라리아 유행지역 주민의 항체보유율 변화 1. The study for the malaria eradication 1. The seasonal changes of antibodies of inhabitants lived in malaria epidemic areas

김동수,이형우,조신형,인태숙,이혜정,이욱교,김남렬,신민철,문승욱,임현정,고승연,이종수 국립보건연구원 2000 국립보건원보 Vol.37 No.-

Optical and electrical improvements of semipolar (11-22) GaN-based light emitting diodes by Si doping of n-GaN template

Lee, J.H.,Han, S.H.,Song, K.R.,Lee, S.N. Elsevier Sequoia 2014 JOURNAL OF ALLOYS AND COMPOUNDS Vol.598 No.-

We report that the performance of semipolar (11-22) GaN-based light-emitting diodes (LEDs) was improved by increasing the Si-doping concentration of n-type GaN templates. In-plane and out-of plane high-resolution X-ray diffraction demonstrated that crystal defects such as threading dislocation, partial stacking faults and basal stacking faults, were significantly decreased by increasing the Si-doping concentration. This resulted in the increase of carrier mobility due to reduction of the defect-scattering effect. Furthermore, the quality of InGaN/GaN quantum-well interfaces was improved by increasing the Si-doping concentration of the n-type GaN template. Based on these results, we suggest that the light-output power and operation voltage of semipolar (11-22) GaN-based LEDs would be improved by increasing Si doping concentration of n-type GaN templates.

Blood genomic profiling in extracranial- and intracranial atherosclerosis in ischemic stroke patients

Lee, H.B.,Kim, Y.,Yoo, H.,Lee, J.M.,Kim, Y.K.,Kim, N.K.,Kim, J.K.,Oh, S.H. Pergamon Press ; Elsevier Science Ltd 2014 Thrombosis research Vol.134 No.3

Objective: Extracranial- and intracranial atherosclerosis (ECAS and ICAS) have been suggested to have different pathogeneses. Blood genomic profiling may identify their unique molecular signatures. Methods: Whole gene microarray of peripheral blood was performed in 24 patients with acute ischemic stroke (ECAS, n=12; ICAS, n=12) and 12 healthy controls. Differential gene expression and gene set enrichment analysis (GSEA) were conducted. Plasma resistin levels were compared across independent samples of stroke patients with ECAS (n=39), ICAS (n=20), and small vessel disease (SVD, n=57). Results: Microarray revealed that 144 and 24 transcripts were altered in ECAS and ICAS, respectively, compared to controls. All the transcripts that were differentially expressed in ICAS were also differentially expressed in ECAS. A total of 120 transcripts were differentially expressed only in ECAS. Gene sets related to immune response and protein metabolism were altered in both ECAS and ICAS, but the magnitude of gene alteration was higher in ECAS than in ICAS. Several genes of interest including RETN, IRF5, CD163, and CHST13 were more highly expressed in ECAS than in ICAS. Circulating resistin levels were elevated in independent samples of ECAS, but not in those of ICAS, compared to those of SVDs. Conclusions: ECAS showed prominent genomic alteration related to immune response compared to ICAS. Although there was no ECAS-specific gene to be identified on microarray, the level of resistin expression was high on peripheral blood in ECAS, suggesting that resistin is associated with the pathogenesis of ECAS.