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111.
Layer-by-layer (LbL) deposition of CuInS2 (CIS) thin films at room temperature (25 °C) from alkaline CuSO4 + In2(SO4)3 and Na2S precursor solutions was reported. The method allowed self-limited growth of CIS films with nanocrystalline structure and composed of densely packed nanometer-sized grains. The as-deposited CIS film was 250 nm thick and composed of closely packed particles of 20-30 nm in diameter. The alkaline cationic precursor solution was obtained by dissolving CuSO4 and InSO4 in deionized water with a appropriate amount of hydrazine monohydrate (H-H) and 2,2′,2″-nitrilotriethanol (TEA). CIS films were annealed at 200 °C for 2 h and effect of annealing on structural, optical, and surface morphological properties was thoroughly investigated by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV-vis spectrometer, C-V, and water contact angle techniques, respectively. 相似文献
112.
For a strong solution u(x,t) of the Navier-Stokes equations in exterior domain Ω in Rn where n=2,3, we study the time decay of ‖α|x|u(t)Lp‖ for α<n. When a domain has a boundary, pressure term makes an obstacle since we do not have enough information on the pressure term near the boundary. To overcome the difficulty, we adopt the ideas in [H.-O. Bae, B.J. Jin, Temporal and spatial decay rates of Navier-Stokes solutions in exterior domains, Bull. Korean Math. Soc. 44 (3) (2007) 547-567; H.-O. Bae, B.J. Jin, Asymptotic behavior for the Navier-Stokes solutions in 2D exterior domains, J. Funct. Anal. 240 (2006) 508-529] and we will extend Bae and Jin's results by modifying their methods. 相似文献
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114.
R. Hartschuh Y. Ding J. H. Roh A. Kisliuk A. P. Sokolov C. L. Soles R. L. Jones T. J. Hu W. L. Wu A. P. Mahorowala 《Journal of Polymer Science.Polymer Physics》2004,42(6):1106-1113
For a range of applications, polymers are now being patterned into nanometer‐sized features. In these applications, the robust mechanical properties of the nanostructures are critical for performance and stability. Brillouin light scattering is presented as a nondestructive, noncontact tool used to quantify the elastic constants in such nanostructures. We demonstrate this through a series of thin films and parallel ridges and spacings (gratings) with ridge widths ranging from 180 to 80 nm. For the set of films and structures presented here, the room‐temperature elastic moduli did not change with decreasing film thickness or grating ridge width, and this implied that one‐dimensional and two‐dimensional confinement‐induced changes of the mechanical properties were not significant down to feature sizes of 80 nm. Additionally, Brillouin spectra of submicrometer gratings revealed new modes not present in the spectra of thin films. The origin of these new modes remains unclear. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1106–1113, 2004 相似文献
115.
Young Hae Roh Jong Woo Bae Gil Soo Nam Joong Hyup Kim Sung Hoon Kim Cheol Min Yoon 《合成通讯》2013,43(1):81-86
The reaction of 6-[1-Aza-2-(dimethylamino)prop-l-enyl]-5-iodo-1,3-dimethyluracil (3) with various olefins in the presence of a catalytic amount of Pd(OAc)2 and 1.5 equiv. of K2CO3 in DMF at 120 °C gave the pyrido[2,3-d]pyrimidine derivatives (5a-b and 7a-d) in moderate to high yield. 相似文献
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117.
H.-S. Roh 《The European Physical Journal C - Particles and Fields》2001,22(2):359-377
Quantum weakdynamics (QWD) as an gauge theory with the vacuum term is considered to be the unification of the electroweak interaction as an gauge theory. The grand unification of beyond the standard model is established by the group . The grand unified interactions break down to weak and strong interactions at a new grand unification scale, GeV, through dynamical spontaneous symmetry breaking (DSSB); the weak and strong coupling constants are the same, , at this scale. DSSB is realized by the condensation of scalar fields, postulated to be spatially longitudinal components
of gauge bosons, instead of Higgs particles. Quark and lepton family generation, the Weinberg angle , and the Cabbibo angle are predicted. The electroweak coupling constants are , , , and ; there are symmetric isospin interactions.
Received: 21 January 2001 / Published online: 21 November 2001 相似文献
118.
119.
Su Yeon Kim Hwa Jung Roh Da Young Seo Ji Yeon Ryu Junseong Lee Jae Nyoung Kim 《Tetrahedron letters》2017,58(10):914-918
Base-catalyzed domino reaction between N-methylisatin and methyl propiolate afforded four diastereomeric dispiro-1,3-dioxolane bisoxindoles. The reaction mechanism involved sequential 1,2-addition of acetylide anion to the carbonyl group of isatin, 1,2-addition of the resulting oxyanion to a second molecule of isatin, and the final 5-exo-dig cyclization process. 相似文献
120.
Vellaiappillai Tamilavan Kyung Hwan Roh Rajalingam Agneeswari Dal Yong Lee Shinuk Cho Youngeup Jin Sung Heum Park Myung Ho Hyun 《Journal of polymer science. Part A, Polymer chemistry》2014,52(24):3564-3574
Pyrrolo[3,4‐c]pyrrole‐1,3(2H,5H)‐dione (DPPD)‐based large band gap polymers, P(BDT‐TDPPDT) and P(BDTT‐TDPPDT), are prepared by copolymerizing electron‐rich 4,8‐bis(2‐ethylhexyloxy)benzo[1,2‐b:4,5‐b′]dithiophene (BDT) or 4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b:4,5‐b′]dithiophene (BDTT) unit with novel electron deficient 2,5‐dioctyl‐4,6‐di(thiophen‐2‐yl)pyrrolo[3,4‐c]pyrrole‐1,3(2H,5H)‐dione (TDPPDT) unit. The absorption bands of polymers P(BDT‐TDPPDT) and P(BDTT‐TDPPDT) cover the region from 300 to 600 nm with an optical band gap of 2.11 eV and 2.04 eV, respectively. The electrochemical study illustrates that the highest occupied/lowest unoccupied molecular orbital energy levels of P(BDT‐TDPPDT) and P(BDTT‐TDPPDT) are ?5.39 eV/?3.28 eV and ?5.44 eV/?3.40 eV, respectively. The single layer polymer solar cell (PSC) fabricated with a device structure of ITO/PEDOT:PSS/P(BDT‐TDPPDT) or P(BDTT‐TDPPDT):PC70BM+DIO/Al offers a maximum power conversion efficiency (PCE) of 6.74% and 6.57%, respectively. The high photovoltaic parameters such as fill factor (~72%), open circuit voltage (Voc, ~0.90 V), incident photon to collected electron efficiency (~76%), and PCE obtained for the PSCs made from polymers P(BDT‐TDPPDT) and P(BDTT‐TDPPDT) make them as promising large band gap polymeric candidates for PSC application. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 3564–3574 相似文献