• Title/Summary/Keyword: Pd/Si

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Submicrospheres as Both a Template and the Catalyst Source. Silica Submicro-reactor Dotted with Palladium Nanoparticles as Catalysts

  • Kim, Sung Min;Noh, Tae Hwan;Jung, Ok-Sang
    • Bulletin of the Korean Chemical Society
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    • v.34 no.4
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    • pp.1127-1130
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    • 2013
  • Formation of the monodisperse submicrospheres consisting of ionic palladium(II) complexes, $[(Me_4en)Pd(L)]_2(X)_4$($Me_4en$ = N,N,N',N'-tetramethylethylenediamine; L = bis(4-(4-pyridylcarboxyl)phenyl)methane; $X^-=BF_4{^-}$ and $ClO_4{^-}$), has been carried out without any templates or additives. The submicrospheres were coated with silicates, and then calcined in air at $550^{\circ}C$ for 1 h, to efficiently form hollow-spherical $SiO_2$ submicro-reactors dotted with palladium(0) nanoparticles (PdNPs). That is, the submicrospheres act as both a template and a source of the palladium metal nanoparticles. The submicro-reactors containing nano-catalysts have been characterized by means of SEM, TEM, and XPS. Notably, the reactors were proved to be very effective for Suzuki-Miyaura cross-coupling and hydrogenation reactions.

Effect of retinoic acid and delta-like 1 homologue (DLK1) on differentiation in neuroblastoma

  • Kim, Yu-Ri
    • Nutrition Research and Practice
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    • v.4 no.4
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    • pp.276-282
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    • 2010
  • The principal objective of this study was to evaluate the chemopreventive and therapeutic effects of a combination of all-trans-retinoic acid (RA) and knockdown of delta-like 1 homologue (Drosophila) (DLK1) on neuroblastoma, the most common malignant disease in children. As unfavorable neuroblastoma is poorly differentiated, neuroblastoma cell was induced differentiation by RA or DLK1 knockdown. Neuroblastoma cells showed elongated neurite growth, a hallmark of neuronal differentiation at various doses of RA, as well as by DLK1 knockdown. In order to determine whether or not a combination of RA and DLK1 knockdown exerts a greater chemotherapeutic effect on neuroblastoma, cells were incubated at 10 nM RA after being transfected with SiRNA-DLK1. Neuronal differentiation was increased more by a combination of RA and DLK1 knockdown than by single treatment. Additionally, in order to assess the signal pathway of neuroblastoma differentiation induced by RA and DLK1 knockdown, treatment with the specific MEK/ERK inhibitors, U0126 and PD 98059, was applied to differentiated neuroblastoma cells. Differentiation induced by RA and DLK1 knockdown increased ERK phosphorylation. The MEK/ERK inhibitor U0126 completely inhibited neuronal differentiation induced by both RA and DLK1 knockdown, whereas PD98059 partially blocked neuronal differentiation. After the withdrawal of inhibitors, cellular differentiation was fully recovered. This study is, to the best of our knowledge, the first to demonstrate that the specific inhibitors of the MEK/ERK pathway, U0126 and PD98059, exert differential effects on the ERK phosphorylation induced by RA or DLK1 knockdown. Based on the observations of this study, it can be concluded that a combination of RA and DLK1 knockdown increases neuronal differentiation for the control of the malignant growth of human neuroblastomas, and also that both MEK1 and MEK2 are required for the differentiation induced by RA and DLK1 knockdown.

Calculation and measurement of optical coupling coefficient for bi-directional tancceiver module (양방향 송수신모듈 제작을 위한 광결합계수의 계산 및 측정)

  • Kim, J. D.;Choi, J. S.;Lee, S. H.;Cho, H. S.;Kim, J. S.;Kang, S. G.;Lee, H. T.;Hwang, N.;Joo, G. C.;Song, M. K.
    • Korean Journal of Optics and Photonics
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    • v.10 no.6
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    • pp.500-506
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    • 1999
  • We designed and fabricated a bidirectional optical transceiver module for low cost access network. An integrated chip forming a pin-PD on an 1.3 urn FP-LD was assembled by flip-chip bonding on a Si optical bench, a single mode fiber with an angled end facet was aligned passively with the integrated chip on V-groove of Si-optical bench. Gaussian beam theory was applied to evaluate the coupling coefficients as a function of some parameters such as alignment distance, angle of fiber end facet, vertical alignment error. The theory is also used to search the bottle-neck between transmittance and receiving coupling efficiency in the bi-directional optical system. Tn this paper, we confirmed that reduction of coupling efficiency by the vertical alignment error between laser beam and fiber core axis can be compensated by controlling the fiber facet angle. In the fabrication of sub-module, a'||'&'||' we made such that the fiber facet have a corn shape with an angled facet only core part, the reflection of transmitted laser beam from the fiber facet could be minimized below -35 dE in alignment distance of 2: 30 /J.m. In the same condition, transmitted output power of -12.1 dEm and responsivity of 0.2. AIW were obtained.

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The Revised Version of the Minnesota Multiphasic Personality Inventory in Korean College Students with Symptoms of Temporomandibular Disorders

  • Park, Hye Sook
    • Journal of Oral Medicine and Pain
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    • v.44 no.1
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    • pp.16-24
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    • 2019
  • Purpose: The purpose of this study was to assess the association of personality characteristics with temporomandibular disorders (TMDs). Methods: Four hundred and fifty one college students in Gyeonggi-do completed the revised version of the Minnesota Multiphasic Personality Inventory (MMPI-2) and a questionnaire and collected data were analyzed by IBM SPSS Statistics ver. 25.0 software (IBM Co., Armonk, NY, USA). Results: Mean values of the number of positive answers of TMD symptoms were significantly higher in higher scorers on hypochondriasis (Hs), depression (D), paranoia (Pa) (Hs>60, D>64, Pa>59) (p<0.01). Higher scorers on Hs, hysteria (Hy), schizophrenia (Sc), Pa, psychasthenia (Pt) (Hy>64, Sc>64, Pt>64) exhibited significantly higher mean values of the number of positive answers of contributing factors for TMD (p<0.01, p<0.001). Low scorers on social introversion ($Si{\leq}44$) exhibited significantly lower mean value of the number of positive answers of contributing factors for TMD than high or moderate scorers on Si (Si>64, 45-64) (p<0.01, p<0.05). The percentage of subjects who responded that they had at least one TMD symptom was significantly higher in higher scorers on Hs, Pt, D (p<0.05, p<0.01). The significantly higher percentage of higher scorers on D, Pa reported at least one contributing factor for TMD (p<0.05). The percentage of subjects who responded that they had at least one TMD symptom or one contributing factor for TMD was significantly different among three groups divided by T-score on Si (p<0.01, p<0.05). T-scores of Hs, D, Hy, Pt and Sc showed significant correlation with the numbers of TMD symptoms and contributing factors for TMD, respectively (p<0.001). A correlation was found between T-score of Pd and the number of TMD symptoms (p<0.001). T-score of Si correlated to the number of contributing factors for TMD (p<0.001). Conclusions: Most clinical scales of MMPI-2 were found to be related to TMD. Psychological assessment including MMPI-2 may play a role in predicting treatment outcome and planning treatment of TMD.

Phase Behaviors of the GAP/PTMG Polyurethanes Chain Extended with 3-Azidopropane-1,2-Diol (3-Azidopropane-1,2-diol로 쇄연장된 GAP/PTMG 폴리우레탄의 상거동)

  • Kim, Hyoung-Sug;You, Jong-Sung;Kweon, Jung-Ohk;Kim, Jung-Su;Lee, Tong-Sun;Noh, Si-Tae;Jang, Young-Ok;Kim, Dong-Kuk;Kwon, Sun-Kil
    • Applied Chemistry for Engineering
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    • v.21 no.4
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    • pp.377-384
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    • 2010
  • We perform a comparative study to investigate the properties of the new energetic chain extender (AzPD). A series of poly(glycidyl azide)/poly(tetramethylene oxide)-based energetic segmented polyurethane (GAP/PTMG ESPU) with different chain extender, which is 3-azidopropane-1,2-diol (AzPD), 1,4-butane diol (1,4-BD), or 1,5 pentane diol (1,5-PD), was synthesized by solution polymerization in dimethyl formamide (DMF) and their phase behaviors were investigated. The ESPUs were characterized with Fourier transform infrared-attenuated total reflection spectroscopy (ATR FT-IR), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). The results of the ATR FT-IR analysis of the urethane carbonyl group region showed that the 'free' C=O fraction was higher in GAP/PTMG AzESPU (0.5) than GAP/PTMG BDESPU (0.44) and GAP/PTMG PDESPU (0.41) for 7 days samples after preparation and that it was similar in the range of 0.26~0.29 for three 60 days ESPU samples. DMA curves of the GAP/PTMG AzESPU for 7 days samples showed amorphous polymers, but GAP/PTMG BDESPU and GAP/PTMG PDESPU showed viscoelastic behaviors with rubbery plateau and the flow region. However, DMA curves of the GAP/PTMG AzESPU for 60 days samples showed viscoelastic behaviors with rubbery plateau and the flow region like GAP/PTMG PDESPU, but GAP/PTMG BDESPU did not show the flow region. From phase behaviors with ATR FT-IR, DSC and DMA analysis, GAP/PTMG AzESPU showed good phase-mixing between components. However, it represented viscoelastic behavior of TPE similar to GAP/PTMG PDESPM according to phase equilibrium progress with aging time.

Spatial Fragmentation Analysis of Upland Fields Using Farm Manager Registration Information (농업경영체 등록정보를 활용한 밭 경작지의 공간적 파편화 특성 분석)

  • Lee, Jimin;Yoo, Seung-Hwan;Oh, Yun-Gyeong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.60 no.2
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    • pp.13-24
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    • 2018
  • As food consumption pattern changes (reduced rice consumption and increased consumption of fresh vegetables), managing upland fields became a greater priority. However, the agricultural infrastructure projects have been focused on rice farming, and the infrastructure level to support dry fields cultivation is insufficient. The purpose of this study was to spatial distribution analysis of these dry fields with farm manager registration information. Using FRAGSTATS, we analyzed landscape indices (TA/CA, NP, PD, LSI, LPI, PLADJ, COHESION, CONNECT, AI) of farmlands in which farmers in 13 regions (Si or Gun) cultivated dry-field crops. As results of this analysis, the total area of the fields in Naju-si, Hampyeong-gun and Suncheon-si were found to be wider, but the average area of a patch in Youngam-gun, Hampyeong-gun and Jangseong-gun were wider than other regions. On average, each farmer had farmlands containing of 1.7~2.4 patches and cultivated crops in fields of 0.2~0.5 ha. Farmlands of Hampyeong-gun, Youngam-gun, Naju-si showed high values in adjacency indices, however the farmlands of Suncheon and Gwangyang showed fragmented distribution with low values in adjacency indices. These results of fragmentation analysis of farmlands could be used when we establish the plan of an agricultural infrastructure project or select places for a collaborative agricultural management business promotion project.

Pb-based piezoelectric thick films prepared by a screen printing (Screen printing에 위한 Pb계 압전세라믹스 후막의 제조)

  • Paik, D.S.;Shin, H.S.;Sim, S.H.;Park, Y.W.;Kang, C.Y.;Shin, H.Y.;Yoon, S.J.
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1541-1543
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    • 1999
  • Screen printing에 의해 압전 후막을 제조하기 위하여 약 $0.6{\mu}m$의 평균 입자 크기를 갖는 PMN-PZT와 PAN-PZT 분말을 산화물 혼합법에 의해 제조하였다. 치밀한 후막의 제조를 위한 분말과 유기물의 비율은 분산이 가능한 범위에서 80:20 (분말:유기물)의 중량비를 나타내었다 사용된 기판과 하부전극은 각각 $SiO_2$/Si와 AgPd 였으며, 후막 제조시 박리 및 균열현상은 발생되지 않았다. 프린트된 후막은 건조온도와 무관한 미세구조를 나타내었으며, 보다 치밀한 구조를 갖는 후막의 제조를 이해 입자의 분산 및 열처리 조건 그리고 기판과의 매칭에 대해 연구가 계속되어야 할 것으로 생각된다.

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Selective Contact Hole Filling by electroless Ni Plating (무전해 Ni 도금에 의한 선택적 CONTACT HOLE 충전)

  • 우찬희;권용환;김영기;박종완;이원해
    • Journal of the Korean institute of surface engineering
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    • v.25 no.4
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    • pp.189-206
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    • 1992
  • The effect of activation and electroless nickel plating conditions on contact properties was investi-gated for selective electroless nickel plating of Si wafers in order to obtain an optimum condition of con-tact hole filling. According to RCA prosess, p-type silicon (100) surface was cleaned out and activated. The effects of temperature, DMAB concentration, time, and strirring were investigated for activation of p-type Si(100) surface. The optimal activation condition was 0.2M HF, 1mM PdCl2, 2mM EDTA,$ 70^{\circ}C$, and 90sec under ultrasonic vibration. In electroless nickel plating, the effect of temperature, DMAB concentra-tion, pH, and plating time were studied. The optimal plating condition found was 0.10M NiSO4.H2O, 0.11M Citrate, pH 6.8, $60^{\circ}C$, 30minutes. The contact resistance of films was comparatively low. It took 30minutes to obtain 1$\mu\textrm{m}$ thick film with 8mM DMAB concentration. The film surface roughness was improved with decreasing temperature and decreasing pH of the plating solution. The best quality of the film was obtained at the condition of temperature $60^{\circ}C$ and pH 6.0. The micro-vickers hardness of film was about 800Hv. Plating rate of nickel on the hole pattern was slower than that of nickel on the line pattern.

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The effect of rapid thermal annealing treatment for ferroelectric properties of PZT thin films (RTA를 이용한 후열처리가 PZT 박막의 강유전 특성에 미치는 영향)

  • Ju, Pil-Yeon;Park, Young;Jeong, Kyu-Won;Lim, Dong-Gun;Song, Joon-Tae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.136-139
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    • 1999
  • The post-annealing treatments on RF (Radio Frequency) magnetron sputtered PZI(Pb$\_$1.05/(Zr$\_$0.52/, Ti$\_$0.48/)O$_3$thin films(4000${\AA}$) have been investigated. for a structure of PZT/Pt/Ti/SiO$_2$/Si Crystallization pproperties of PZT films were strongly dependent on RTA(Rapid Thermal Annealing) annealing temperature. We were able to obtain a perovskite structure of PZT at a low temperature of 600$^{\circ}C$. P-E curves of Pd/PZT/Pt capacitor annealed at 700$^{\circ}C$ demonstrate typical hysteresis loops. The measured values of P$\_$r/, E$\_$c/, by post annealed at 700$^{\circ}C$ were 12.1 ${\mu}$C/$\textrm{cm}^2$, 120KV/cm respectively.

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A Study on the Characteristics of MMPI Profile and Personality in Patients with Hwa-byung (화병환자의 MMPI 프로파일과 성격특성 연구)

  • Kim, Ji-Hwon;Park, Bo-Ra;Jang, Hyun-Ho;Kim, Tae-Heon;Lyu, Yeoung-Su;Kang, Hyung-Won
    • Journal of Oriental Neuropsychiatry
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    • v.20 no.3
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    • pp.189-203
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    • 2009
  • Objectives : This study was to analyze characteristics of MMPI profile, personality and defensive mechanism on 32 Hwa-byeng patients. Methods : 32 Hwa-byeng patients and 28 normal control group were administered the MMPI. The characteristics of MMPI profile and the clinical scales of personality and defensive mechanism were analyzed statistically. Results : 1. Half of female Hwa-byeng patients are in their forties, twelve patients are high school graduates, housewives seem to have Hwa-byeng more than workers, and married ones have Hwa-byeng more than singles, divorcees or separated one 2. 60.6% patients are getting stressed from their husbands(the specific reasons are infidelity(55%), incapability(25%) and violence(20%)). And the rest are from in-law(28.8%), children(6.4%) and their own parents(3.2%). 3. MMPI profile of Hwa-byeng patients appeared as a type of 3-1 elevated by the scale of 3(Hy) and 1 (Hs). And Hwa-byeng patients appeared significantly high in the rest of scales except L, K, Mf and Ma scales comparing to control group. 4. Hwa-byeng patients were classified into 3 groups. First group is "V" type which is high in K scale and low in 3 (Hy), 4(Pd), 6(Pa). Second group is "V" type which is high in K scale and high in 3(Hy), 4(Pd), 6(Pa). Third group is high in F scale and high in 1(Hs), Z(D), 3(Hy), 4(Pd), 6(Pa), 7(Pt), 8(Sc) and 0(Si). 5. The analysis on MMPI profiles indicates that the thirties are highier in F scale than the fifties, the fifties are highier in Hy scale than the forties, workers are highier in Pd scale than housewives, singles or divorcees are highier in Pa scale than the married. 6. The characteristics of personality in Hwa-byeng patients are as follows. They are significantly lower in HST, NAR and very higher in CPS, PAG, DEP, STY, AVD, SZD comparing to control group. Especially in AVD and SZD scales are appeared the highest.

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