Poly(ethylenimine)-Stabilized Hollow Gold-Silver Bimetallic Nanoparticles: Fabrication and Catalytic Application

Shin, Kuan-Soo,Kim, Ji-Hoon,Kim, In-Hyun,Kim, Kwan Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.3

Hollow gold-silver bimetallic nanoparticles (AuAg-HNPs) have been synthesized and their optical and structural properties were characterized. Initially Ag nanoparticles (Ag-NPs) were prepared using poly(ethylenimine) (PEI) as a reducing and a stabilizing agent simultaneously. AuAg-HNPs could then be synthesized via galvanic replacement reaction in a PEI aqueous solution by reacting sacrificial Ag template with a precursor compound of Au, i.e., $HAuCl_4$. Due to the presence of abundant amine functional groups in PEI, which could act as the dissolving ligand for AgCl, the precipitation problem of $Ag^+$ in the presence of Cl from $HAuCl_4$ salt was avoided. On this basis, the relatively high concentrations of $HAuCl_4$ and PEI-stabilized Ag nanoparticles could be used for the fabrication of AuAg-HNPs. Because of their increased surface areas and reduced densities, the AuAg-HNPs were expected and confirmed to outperform their solid counterparts in applications such as catalysis for the reduction of 4-nitrophenol in the presence of $NaBH_4$.

Temperature-dependent magnetic and local structural properties of diamagnetic a-HgI2

여순목,Jae-Kuan Son,Chang-In Park,황인희,Zhenlan Jin,Jang Ho Ha,Sang-Wook Han 한국물리학회 2016 Current Applied Physics Vol.16 No.9

We examined the temperature-dependent magnetic and structural properties of a-HgI2 in the temperature range of 300e400 K using temperature-dependent DC-magnetization, x-ray diffraction (XRD), and x-ray absorption fine structure (XAFS) measurements. DC-magnetization measurements of a-HgI2 single crystals show a sudden reduction of diamagnetic susceptibility for T > 350 K. XRD measurements with Rietveld refinements reveal a small but substantial amount of decrease in disorder in both Hg and I sites above 350 K, with neither a structural transition nor vacancies in the temperature range. XAFS demonstrates a shift of the I K edge for T > 350 K but no changes at the Hg L3 edge. A stronger bonding of Hg-I pairs above 350 K likely affects the electrons in the outermost shells of iodine atoms and enhances the intrinsic paramagnetic properties, thereby producing a reduction in diamagnetism.

Effects of wet-oxidized 4H-SiC annealed in HNO₃/H₂O vapour

Poobalan, Banu,Moon, Jeong Hyun,Kim, Sang-Cheol,Joo, Sung-Jae,Bahng, Wook,Kang, In Ho,Kim, Nam-Kyun,Cheong, Kuan Yew Emerald Group Publishing Limited 2013 Microelectronics international Vol.31 No.1

<B>Purpose</B> - The high density of defects mainly attributed to the presence of silicon oxycarbides, residual C clusters, Si- and C-dangling bonds at or near the SiO<SUB>2</SUB>/SiC interface degrades the performance of metal-oxide-semiconductor (MOS) devices. In the effort of further improving the quality and enhancement of the SiC oxides thickness, post-oxidation annealed by a combination of nitric acid (HNO<SUB>3</SUB>) and water (H<SUB>2</SUB>O) vapor technique on thermally grown wet-oxides is introduced in this work. The paper aims to discuss these issues. <B>Design/methodology/approach</B> - A new technique of post-oxidation annealing (POA) on wet-oxidized n-type 4H-SiC in a combination of HNO<SUB>3</SUB> and H<SUB>2</SUB>O vapor at various heating temperatures (70°C, 90°C and 110°C) of HNO<SUB>3</SUB> solution has been introduced in this work. <B>Findings</B> - It has been revealed that the samples annealed in HNO<SUB>3</SUB> +?H<SUB>2</SUB>O vapour ambient by various heating temperatures of HNO<SUB>3</SUB> solution; particularly at 110°C is able to produce oxide with lower interface-state density and higher breakdown voltage as compared to wet-oxidized sample annealed in N2 ambient. The substrate properties upon oxide removal show surface roughness reduces as the heating temperature of HNO<SUB>3</SUB> solution increases, which is mainly attributed due to the significant reduction of carbon content at the SiC/SiO<SUB>2</SUB> interface by C=N passivation and CO or CO<SUB>2</SUB> out-diffusion. <B>Originality/value</B> - Despite being as a strong oxidizing agent, vaporized HNO<SUB>3</SUB> can also be utilized as nitridation and hydrogen passivation agent in high temperature thermal oxidation ambient and these advantages were demonstrated in 4H-SiC.

Effects of Long-acting Injectable 3-Monthly Paliperidone Palmitate on the Clinical and Social Performance of Patients with Schizophrenia

Jihoon Oh(Jihoon Oh),Jihye Oh(Jihye Oh),Dong Wook Kim(Dong Wook Kim),HyunChul Youn(HyunChul Youn),Sae-Hoon Kim(Sae-Hoon Kim),Soo In Kim(Soo In Kim),In Won Chung(In Won Chung),Kuan Shu Wang(Kuan Shu Wa 대한정신약물학회 2023 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.21 No.1

Objective: To investigate the effects of long-acting injectable 3-monthly paliperidone palmitate on the clinical and social functioning of patients with schizophrenia. Methods: This study enrolled patients with schizophrenia receiving long-acting injectable 1-monthly paliperidone palmitate for at least 4 months and who subsequently received 3-monthly paliperidone palmitate. Accordingly, 418 patients were followed up for 24 weeks. Their clinical symptoms and social functioning were measured using the Clinical Global Impression-Severity of Illness and Personal and Social Performance scales. Results: The Personal and Social Performance total score was significantly higher after 3-monthly paliperidone palmitate treatment than at baseline (baseline vs. week 24: 54.3 ± 18.0 vs. 61.0 ± 14.5 [mean ± standard deviation]; p < 0.001; Wilcoxon signed-rank test); the proportion of patients in the mildly ill group (scores 71−100) also increased significantly (baseline vs. week 24: 16.5% vs. 20.6%; p < 0.001; McNemar-Bowker test). The mean Clinical Global Impression-Severity of Illness score decreased significantly (baseline vs. week 24: 3.7 ± 1.0 vs. 3.4 ± 0.9; p < 0.001; Wilcoxon signed-rank test), as did the proportion of patients in the severely ill group (baseline vs. week 24: 4.1% vs. 2.1%; p < 0.001; McNemar-Bowker test). Conclusion: Continuous 3-monthly paliperidone palmitate treatment significantly enhances the personal and social performance of patients with schizophrenia and reduces the proportion of those with severe illness. These findings suggest that long-acting injectable antipsychotic administration at intervals longer than 1 month might improve the social functioning of and promote return to activities of daily living in patients with schizophrenia.

우리나라 降雨量의 確率分布型에 관한 硏究

權鍾仁 건국대학교 1987 論文集 Vol.3 No.-

The purpose of this study deals the derivation of the maximum rainfall depth related to the duration of rainfall and frequncy for 14 meteorological stations in Korea. The rainfall data used in this study are duration of 10min, 60min, 8hrs and 24hrs. The 24 years historical records are consist of the year from 1961 to 1984. The five distributions of the rainfall frequency are selected such as 2 parameter log-normal, Type I extremal, log-Pearson Type III, Gamma and Pearson Type III. The results are concluded as follows; 1.The relationship between rainfall depth with duration and frequency are fairly good approximation in function of *****(p. 218) 2.The results will be the effective standard to determine the design storm for sewer or culvert design. 3.According to this study, the probability distribution of rainfall in Korea shows that there are no difficulties to choose any five type of distributions.

Tuning the interparticle distances in self-assembled gold nanoparticle films with their plasmonic responses

Kim, In-Hyun,Kim, Ji Hoon,Choi, Jeong-Yong,Shin, Chae Ho,Kim, Jung-Hwan,Bae, Gyun-Tack,Shin, Kuan Soo Elsevier 2019 Chemical physics letters Vol.715 No.-

<P><B>Abstract</B></P> <P>This study presents the fabrication and characterization of imine-functionalized Au nanoparticle (Au NP) film using Poly (ethyleneimine) (PEI) as a reducing and surface stabilizing reagent. The PEI-capped Au NPs can be self-assembled at the water-hexane interface by adding alcohol containing alkanethiol. Furthermore, large-area film made from PEI and alkanethiol-capped Au NPs is produced on a glass substrate with varying interparticle distances that can be controlled by the alkyl chain lengths, ranging from C2 (ethanethiol), C4 (1-butnaethiol), C6 (1-hexanethiol), C8 (1-octanethiol), to C10 (1-decanethiol) at the water-hexane interface. These 2D films show strong collective localized surface plasmon resonance (LSPR) extinction bands that are tunable via near-field coupling of adjacent Au NPs. Pronounced chain-length-dependent red shifts of the SPR bands have been observed for the PEI-capped Au films. The obtained PEI-capped Au films exhibit distinct interparticle-distance-dependent SERS characteristics.</P> <P><B>Highlight</B></P> <P> <UL> <LI> Investigates the localized surface plasmon resonance (LSPR) properties of 2D film of Au nanoparticles on a glass substrate formed at the water-hexane interface. </LI> <LI> 2D films of the Au nanoparticles with the ability to control the interparticle distances by the alkyl chain lengths of alkanethiol. </LI> <LI> Density functional theory (DFT) calculation and finite-difference time domain (FDTD) simulation have been used to confirm the interparticle distances. </LI> <LI> Au nanoparticles and also exhibit distinct interparticle-distance-dependent surface-enhanced Raman scattering (SERS) characteristics. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

라디에타소나무(Pinus radiata D. Don)의 방사방향에 따른 물리ㆍ조직적 특성

오승원,이권재,정인수 전북대학교 농업과학기술연구소 1998 農大論文集 Vol.29 No.1

This study was carried out in order to investigate the properties of physical and anatomical in Pinus ragdiata D. Don on the radial direction in grown New Zealand. The variation of annual ring width with the annual ring at D. B. H. was highest at the 14th after that slowly decreased along with annual ring. The average annual ring width was 9.35±3.58mm. The variation of latewood percentage with the annual ring at D. B. H. showed a sharp rise from 1st to 18th annual ring after that no variation. The average latewood percentage was 33.43±14.08%. The variation of specific gravity with the annual ring at D. B. H. showed a sharp rise from the 1st to 6th annual ring after that slowly increased along with annual ring. The average specific gravity was 0.59±0.04 in air dry, 0.55±0.04 in oven dry. The variation of tracheid length at D. B. H tendency to increase as the annual ring increase. The average tracheid length was 3.03±0.42mm.

Green Synthesis of Ag Thin Films on Glass Substrates and Their Application in Surface-Enhanced Raman Scattering

Cho, Young Kwan,Kim, In Hyun,Shin, Kuan Soo Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

Nanostructured Ag thin films could be facilely prepared by soaking glass substrates in ethanolic solutions containing $Ag_2O$ powders at an elevated temperature. The formation of zero-valent Ag was corroborated using X-ray diffraction and X-ray photoelectron spectroscopy. The deposition of Ag onto a glass substrate was readily controlled simply by changing the reaction time. Due to the aggregated structures of Ag, the surface-enhanced Raman scattering spectra of benzenethiol could be clearly identified using the Ag-coated glass. The enhancement factor at 514.5 nm excitation estimated using benzenethiol reached $1.0{\times}10^5$ while the detection limit of rhodamine 6G was found to be as low as $1.0{\times}10^{-13}$ M. Since this one-pot fabrication method is eco-friendly and is suitable for the mass production of diverse Ag films, it is expected to play a significant role in the development of surface plasmon-based analytical devices.

계절성 우울증의 신경내분비계 소견

박진한,신정호,송인권 大韓神經精神醫學會 1994 신경정신의학 Vol.33 No.1

The authors investigated neuroendocrine findings of HPA and HPT axes by DCT, DST, and TRH stimulation tests in patients with seasonal depressive disorder(SDD). Subjects were consisted of 11 inpatients(3 males, 8 females) with SDD and 10 control inpatients(10 females) with non-seasonal depressive disorder(NSDD) at the Department of Psychiatry, Yonsei University Wonju Medical College from Sep. 1, 1991 to Dec. 31, 1992. The results were as the following: 1) For DCT in SDD patients, 8 patients(72.6%) showed abnormal cortisol secretion, two(18.2%) with distorted diurnality and six(54.5%) with over-secretion pattern, which did not show significant difference from the control patients. 2) For DST, non-suppression rate was similiar in both group(36.4% for SDD vs 40.0% for NSDD). 3) Blunted TRH stimulation test was noted in 5 among 11 SDD patients(45.5%) compared to 1 among 10 control patients(10.0%). 4) With DST and TRH stimulation test result, the diagnostic senstivity for patients with SDD(63.7%) was higher than that for NSDD patients(50.0%). 5) In patients with SDD, symptoms of decreased libido, increased duration of sleep and daytime drowsiness items by Boyce and Parker were more prevalent(p<0.05), and symptoms of early morning awakening, decreased duration of sleep were less prevalent(p<0.05).

‘후지’ 사과나무 세장방추형에서 하단측지수가 수체생육에 미치는 영향

박우용(Moo-Yoo Park),양상진(Sang-Jin Yang),박정관(Jeng-Kuan Park),최동근(Dong Geun Choi),강인규(In-Kyu Kang) (사)한국생물환경조절학회 2007 시설원예‧식물공장 Vol.16 No.3

‘후지’/M.9에 대한 세장방추형에 적합한 하단측지수 구성을 위하여 하단측지수를 달리하여 수체생육, 광환경, 수량 및 과실품질을 조사하였다. 하단측지수준별 생육은 하단측지수를 5개로 유지했을 때 수폭은 넓었고, 신초장 및 정단신초장은 증가하였다. 수관위치별 수광률은 하단측지수가 5개인 처리구에서 수관상부(지상 150 ㎝)와 수관중부(지상 100 ㎝)에서는 높은 경향을 보였다. 총 단과지 화이수는 측지수에 따라 차이가 없었으나, 수관위치별로 보면 수관하부(지상 120㎝이하)에서 하단측지수가 5개 처리에서 가장 많았으며, 화아의 횡경도 커지는 경향이었다. 과실수량은 하단측지수가 5개에서 가장 많았고, 과중은 하단측지수가 5개와 8개에서 증가하는 경향이었다. 과실특성은 과형지수, 경도, 산함량, Hunter L, b값은 수관위치와 측지수준에 따라 차이가 없었으나, 가용성고형물 함량은 하단측지수가 5개일 때 높았다. 과실의 착색도를 나타내는 Hunter a값은 수광률이 가장 높은 하단측지수를 5개로 유지한 처리구에서 가장 높게 나타났다. This study was carried out to investigate the effects of number of the lower scaffold limbs on tree growth, light penetration, fruit yield, and fruit quality in slender spindle in 6-year-old ‘Fuji’/M.9 apple trees. With regard to the growth by the numbers of the lower scaffold limbs, the width of the tree was wide and the growth of new shoots was increased when the number of the lower scaffold limbs was five. Compare with other treatments, five lower scaffold limbs showed high light-interception on the upper (150 ㎝ above the ground) and middle (100 ㎝ above the ground) canopy. There was no difference in the total number of the flower buds of the spurs according to the number of scaffold limbs, but the number and cross section area of flower bud on the lower canopy (120 ㎝ above the ground) were increased where the number of the lower scaffold limbs was five. Fruit yield was highest in the treated with five lower scaffold limbs and fruit weight tended to increase where the number of the lower scaffold limbs was five or eight. With regard to fruit quality, showed no difference in fruit shape index, firmness, acid content, Hunter Land b value according to the location of canopy and the number of the lower scaffold limbs, but the content of soluble solids was highest treated with five lower scaffold limbs. Hunter a value indicating fruit color was found to be highest treated with five lower scaffold limbs whose light interception was highest.