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921.
922.
Readily Accessible and Predictable Naphthalene‐Based Two‐Photon Fluorophore with Full Visible‐Color Coverage
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Ja Young Koo Cheol Ho Heo Dr. Young‐Hee Shin Dahahm Kim Dr. Chang Su Lim Prof. Dr. Bong Rae Cho Prof. Dr. Hwan Myung Kim Prof. Dr. Seung Bum Park 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14166-14170
Herein we report 22 acedan‐derived, two‐photon fluorophores with synthetic feasibility and full coverage of visible wavelength emission. The emission wavelengths were predicted by computational analysis, which enabled us to visualize multicolor images by two‐photon excitation with single wavelength, and to design a turn‐on, two‐photon fluorescence sensor for endogenous H2O2 in Raw 264.7 macrophage and rat brain hippocampus ex vivo. 相似文献
923.
Chul‐Soon Lee Zhengfei Dai Seong‐Yong Jeong Chang‐Hoon Kwak Bo‐Young Kim Do Hong Kim Prof. Ho Won Jang Joon‐Shik Park Prof. Jong‐Heun Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7102-7107
Monolayers of periodic porous Co3O4 inverse opal (IO) thin films for gas‐sensor applications were prepared by transferring cobalt‐solution‐dipped polystyrene (PS) monolayers onto sensor substrates and subsequent removal of the PS template by heat treatment. Monolayer Co3O4 IO thin films having periodic pores (d≈500 nm) showed a high response of 112.9 to 5 ppm C2H5OH at 200 °C with low cross‐responses to other interfering gases. Moreover, the selective detection of xylene and methyl benzenes (xylene+toluene) could be achieved simply by tuning the sensor temperature to 250 and 275 °C, respectively, so that multiple gases can be detected with a single chemiresistor. Unprecedentedly high ethanol response and temperature‐modulated control of selectivity with respect to ethanol, xylene, and methyl benzenes were attributed to the highly chemiresistive IO nanoarchitecture and to the tuned catalytic promotion of different gas‐sensing reactions, respectively. These well‐ordered porous nanostructures could have potential in the field of high‐performance gas sensors based on p‐type oxide semiconductors. 相似文献
924.
925.
Jyh-Kang Chen Jeng-Rong Ho Yu-Hsuan Lin Raymond Chien-Chao Tsiang 《Applied Physics A: Materials Science & Processing》2011,105(1):249-254
This study characterizes electrical properties of silver thin films with meshed nanostructures fabricated through the photoreduction
of solid silver nitrate thin films using excimer laser irradiation. Variations of mesh morphology as functions of laser irradiation
time and fluences are examined; and the relationship between the film’s electrical resistance and mesh structure are addressed.
The course of nanomesh formation can be separated into two main phases: precipitation of silver nanoparticles as a result
of photoreduction; and, formation of mesh nanostructures through the photothermal effect. The resulting electrical resistance
depends strongly on the mesh nanostructure. With a suitable arrangement of laser fluence and irradiation time, silver thin
films with well interconnected nanomeshes can be fabricated. Results show that silver thin films with low electrical resistivity,
down to 8.5×10−8 Ω m, are easily obtainable. The laser reduction approach takes advantage of the flexibility in local patterning. Moreover,
the reduction is from a solid silver nitrate thin film and is executed in the ambient environment that renders this approach
a potential method for low-temperature fabrication of metallic electrode conductors for organic electronics. 相似文献
926.
Young Bok Ryu Ji Sun Kim Kyeong Ho Kim Yangdo Kim Man Sig Lee 《Research on Chemical Intermediates》2016,42(1):83-93
Zn/Al mixed oxide was prepared by the coprecipitation or the hydrothermal method under different conditions and used as catalyst for synthesis of glycerol carbonate by carbonylation of glycerol with urea. The physical properties of the prepared Zn/Al mixed oxide particles were investigated, as well as their activity as catalyst in the mentioned synthesis. The dried Zn/Al mixed-oxide particles prepared by the coprecipitation method showed higher activity in synthesis of glycerol carbonate than those prepared by the hydrothermal method. The Zn/Al mixed oxide prepared by the coprecipitation method without NaNO3 showed the highest catalytic activity in synthesis of glycerol carbonate. 相似文献
927.
Cheol Ho Choi Klaus Ruedenberg Mark S. Gordon 《Journal of computational chemistry》2001,22(13):1484-1501
The three key translation equations of the fast multipole method (FMM) are deduced from the general polypolar expansions given earlier. Simplifications are introduced for the rotation‐based FMM that lead to a very compact FMM formalism. The optimum‐parameter searching procedure, a stable and efficient way of obtaining the optimum set of FMM parameters, is established with complete control over the tolerable error (ε). This new procedure optimizes the linear scaling with respect to the number of particles for a given ε. In addition, a new parallel FMM algorithm, which requires virtually no internode communication, is suggested that is suitable for the parallel construction of Fock matrices in electronic structure calculations. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1484–1501, 2001 相似文献
928.
By using a generalized Bopp’s shift formulation, instead of the star product method, we investigate the Aharonov–Casher (AC)
effect for a spin-1 neutral particle in non-commutative (NC) quantum mechanics. After solving the Kemmer equations both on
a non-commutative space and a non-commutative phase space, we obtain the corrections to the topological phase of the AC effect
for a spin-1 neutral particle both on a NC space and a NC phase space.
PACS 02.40.Gh, 11.10.Nx, 03.65.-w 相似文献
929.
By using star product method, the He-McKellar-Wilkens (HMW) effect for spin-one neutral particle on noncommutative (NC) space is studied. After solving the Kemmer-like equations on NC space, we obtain the topological HMW phase on NC space where the additional terms related to the space-space non-commutativity are given explicitly. 相似文献
930.
Carriers recombination processes in charge trapping memory cell by simulation 总被引:1,自引:0,他引:1
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We have evaluated the effects of recombination processes in a charge storage layer, either between trapped electrons and trapped holes or between trapped carriers and free carriers, on charge trapping memory cell's performances by numerical simulation. Recombination is an indispensable mechanism in charge trapping memory. It helps charge convert process between negative and positive charges in the charge storage layer during charge trapping memory programming/erasing operation. It can affect the speed of programming and erasing operations. 相似文献