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991.
C.Y. Wang A.W. Liu V.I. Perevalov S.A. Tashkun K.F. Song S.M. Hu 《Journal of Molecular Spectroscopy》2009,257(1):94-104
We present a continuation of our investigation of the second most abundant isotopic species of nitrous oxide, 14N15N16O and 15N14N16O, in the infrared (IR). Our two previous contributions looked at the 3500–9000 cm−1 region for 14N15N16O and 15N14N16O, respectively, in the 3500–9000 cm−1 region. The use of highly enriched isotopologue samples in this study allowed us to go further into the IR, down to 1200 cm−1. A total of 2 2742 transitions have been assigned based on the effective Hamiltonian model, with 108 of them being reported here for the first time. Rovibrational analyses of 98, 101, 8, 3, 6, 1 and 1 bands for the 14N15N16O, 15N14N16O, 15N15N16O, 14N15N18O, 15N14N18O, 14N15N17O and 15N14N17O isotopologues, respectively, were also performed. 相似文献
992.
Shih-Feng Tseng Wen-Tse HsiaoDonyau Chiang Kuo-Cheng HuangChang-Pin Chou 《Applied Surface Science》2011,257(16):7204-7209
The fluorine-doped tin oxide (FTO) thin film deposited on a soda-lime glass substrate was annealed by a defocus ultraviolet (UV) laser irradiation at ambient temperature. The mechanical and optoelectric properties of FTO films annealed by using the various laser processing parameters were reported. After the FTO films were subjected to laser post-annealing, the microhardness were slightly less but the reduced modulus values were larger than that of unannealed FTO films, respectively. The average optical transmittance in the visible waveband slightly increased with increasing the laser annealing energy and scan speed. Moreover, all the sheet resistance of laser annealed films was less than that of the unannealed ones. We found that the sheet resistance decrease was obviously influenced by annealing. The suitable annealing conditions could maintain the film thickness and relief the internal stress generated in the film preparation process to improve the electrical conductivity via decreasing laser energy or increasing scan speed. 相似文献
993.
Undoped and doped ZnO with 1 at.% (atomic percentage) chromium (Cr) was synthesized by RF reactive co-sputtering for oxygen gas sensing applications. The prepared films showed a highly c-oriented phase with a dominant (0 0 2) peak at a Bragg angle of around 34.2°. The operating temperature of the prepared ZnO sensor was around 350 °C and shifted to around 250 °C for the doped ZnO sensor which is lower than that of previously reported work. The sensitivity of the sensor toward oxygen gas was enhanced by doping ZnO with 1 at.% Cr. Good stability and repeatability of the sensor were demonstrated when tested under different concentration of oxygen atmosphere. 相似文献
994.
Costas A. Charitidis 《Applied Surface Science》2010,256(24):7583-8727
In this study, we report on the mechanical properties, failure and fracture modes in two cases of engineering materials; that is transparent silicon oxide thin films onto poly(ethylene terephthalate) (PET) membranes and glass-ceramic materials. The first system was studied by the quazi-static indentation technique at the nano-scale and the second by the static indentation technique at the micro-scale. Nanocomposite laminates of silicon oxide thin films onto PET were found to sustain higher scratch induced stresses and were effective as protective coating material for PET membranes. Glass-ceramic materials with separated crystallites of different morphologies sustained a mixed crack propagation pattern in brittle fracture mode. 相似文献
995.
Seokgeun Jin Byung Jun Jung Chung Kun Song Jeonghun Kwak 《Current Applied Physics》2014,14(12):1809-1812
We introduce a room temperature and solution-processible vanadium oxide (VOx) buffer layer beneath Au source/drain electrodes for bottom-contact (BC) organic field-effect transistors (OFETs). The OFETs with the VOx buffer layer exhibited higher mobility and lower threshold voltages than the devices without a buffer layer. The hole mobility with VOx was over 0.11 cm2/V with the BC geometry with a short channel length (10 μm), even without a surface treatment on SiO2. The channel width normalized contact resistance was decreased from 98 kΩ cm to 23 kΩ cm with VOx. The improved mobility and the reduced contact resistance were attributed to the enhanced continuity of pentacene grains, and the increased work function and adhesion of the Au electrodes using the VOx buffer layer. 相似文献
996.
The preparation and characterization of octadecylsilane, C18, monolayers on indium–tin oxide (ITO) have been studied carefully. A reproducible procedure was developed for the formation of C18/ITO employing octadecyltrimethoxysilane (OTMS) as a monomer. The films were studied by means of electrochemistry, wettability, infrared and atomic force microscopy. All these measurements provide evidence for the formation of a disorganized, ‘brush-type’ monolayer with a maximum surface fractional coverage of 0.90±0.04. The surface coverage can be controlled through the silanization time. The applications and implications of such disorganized monolayers in electroanalytical chemistry are discussed. 相似文献
997.
The significant modifications to our recently constructed electron momentum spectrometer have been implemented. Compared with our previous report, the energy and the angle resolutions are significantly improved and reach △E = 0.45 eV, △θ = ±0.53° and △φ = ±0.84°, respectively. Moreover, the details of data reduction and the relation between azimuthal angle range and the sensitivity are discussed. 相似文献
998.
Dave KIELPINSKI 《Frontiers of Physics in China》2008,3(4):365-381
Atomic ions trapped in ultra-high vacuum form an especially well-understood and useful physical system for quantum information
processing. They provide excellent shielding of quantum information from environmental noise, while strong, well-controlled
laser interactions readily provide quantum logic gates. A number of basic quantum information protocols have been demonstrated
with trapped ions. Much current work aims at the construction of large-scale ion-trap quantum computers using complex microfabricated
trap arrays. Several groups are also actively pursuing quantum interfacing of trapped ions with photons.
相似文献
999.
Nguyen Van Hieu Nguyen Van Duy Pham Thanh Huy Nguyen Duc Chien 《Physica E: Low-dimensional Systems and Nanostructures》2008,40(9):2950-2958
Nb-Pt co-doped TiO2 and the hybrid SWCNTs/Nb-Pt co-doped TiO2 thin films have been prepared by the sol–gel spin-coating process for gas-sensor fabrication. Field emission scanning electron microscope (FE-SEM, TEM and X-ray diffraction (XRD) characterizations indicated that the SWCNTs inclusion did not affect the morphology of the TiO2 thin film and the particle size. Additionally, the SWCNTs were well embedded in the TiO2 matrix. The gas-sensing properties of Nb–Pt co-doped TiO2 thin films with and without SWCNTs inclusion were investigated. The hybrid sensors with the inclusion of different SWCNTs contents are examined to elucidate the effect of SWCNTs content on the gas-sensing properties. Experimental results revealed that the responses to ethanol of Nb–Pt co-doped TiO2 sensors with SWNCTs inclusion increase by factors of 2–5 depending on the operating temperature and the ethanol concentration, compared to that of the sensor without SWCNTs inclusion. Moreover, all hybrid sensors can operate with high sensitivity and stability at a relatively low operating temperature (<335 °C). The responses of the hybrid sensors are greatly affected by SWCNTs content inclusion. The optimized SWCNTs content of 0.01% by weight was obtained for our experiment. The improved gas-sensing performance should be attributed to the additional formation of the p/n junction between SWCNTs (p-type) and TiO2 (n-type). 相似文献
1000.
O. M. Bordun 《Journal of Applied Spectroscopy》2002,69(3):430-433
Luminescence spectra of Y2O3 thin films annealed in air and in vacuum are investigated. It is established that the presence of oxygen vacancies leads to a decrease in the intensity of the luminescence band with a maximum at 3.4 eV (related to emission of selflocalized Frenkel excitons describing the excited state of a molecular ion (YO6)9–) and of the luminescence band with a maximum at 2.9 eV (related to the anion sublattice). It is revealed that the oxygen vacancies also lead to a decrease in the luminescence intensity in the 2.60, 2.35, 2.10. 1.90, and 1.70 eV bands that are related to radiative recombination in the donor–acceptor Y3+–O2– pairs. The donor–acceptor distances are calculated. 相似文献