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991.
Yanbin Qiao Shiwei Feng Cong Xiong Hui Zhu Xiaoyu Ma Yuan Yue 《physica status solidi (a)》2013,210(11):2379-2383
992.
NdxLu1−xVO4 (x = 0, 0.005, 0.02, 0.023, 0.03 and 0.05) series crystals have been grown by the Czochralski method. The results of X-ray powder diffraction experiments show that these crystals belong to the zircon-type structure. The cutoff wavelength of LuVO4 is 330 nm and the transmittance is about 80% in 540-3010 nm. The functional relation of absorption coefficient α at 808 nm on Nd3+-doped concentration Nd in units of atomic % is obtained to be α = 7.649 Nd. The results of Judd-Ofelt analysis show that there is no obvious concentration quenching effect below 3 at.% doped concentrations. The highest output power at 1.06 μm is 1090 mW for Nd0.02Lu0.98VO4 at the pumping power of 6.58 W of a laser diode, the optical-optical conversion efficiency is 16.6% and slope efficiency is 19.4%. 相似文献
993.
Amorphous TaOx thin films were deposited at different temperatures, and the resistance switching properties of the Pt/TaOx/Pt structure were investigated. X‐ray photoelectron spectroscopy showed that the amount of Ta2O5 in the film decreased and the content of Ta suboxides increased substantially when the growth temperature was increased. Unipolar resistance switching near the anode was stable only for TaOx film grown at room temperature. The experimental results revealed the critical effect of the film composition on the resistance switching behavior of TaOx films. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
994.
Roberto Ambrosio Alfonso Torres Carlos Zuiga Mario Moreno Jose Mireles 《physica status solidi (a)》2010,207(7):1708-1712
The presented work meets the requirements for integration of amorphous silicon carbon films with silicon technology in order to obtain a complete optoelectronic system such as light emitting diodes and its electronic readout circuits. The key enabler for this integration scheme is the low temperature of deposition of a‐SiC:H films and an ohmic behavior in the interface metal/a‐SiC:H. In this work, the optimization of the interface Al/a‐SiC:H films are performed by means of thermal annealing timing. The a‐SiC:H films were deposited by enhanced chemical vapor deposition from CH4/SiH4 and C2H2/SiH4 mixtures. The structural and optical properties of the deposited films are presented. An implantation phosphorous dose was used for doping before fabrication of patterned aluminum contacts. The implanted films were electrically characterized by the transfer length method (TLM) measuring a sheet resistance value as low as 171 MΩ/square. The Schottky behavior was improved to ohmic behavior after several hours in thermal annealing treatments at 350 °C, which allows to obtain a reasonable contact resistance values in the range from 8.6 to 26.8 kΩ. 相似文献
995.
Toshiharu Makino Hiromitsu Kato Norio Tokuda Masahiko Ogura Daisuke Takeuchi Kazuhiro Oyama Satoshi Tanimoto Hideyo Okushi Satoshi Yamasaki 《physica status solidi (a)》2010,207(9):2105-2109
We successfully improved a merged diamond diode, namely a Schottky‐pn diode (SPND), which is composed of a fully depleted n‐type active layer sandwiched between a highly doped p+‐type layer and a Schottky metal. According to the analysis of operation mechanisms based on band diagrams, we increased the acceptor concentration in the p+‐type layer in order to decrease the on‐resistance (RonS), and increased the n‐type layer width to reach higher blocking voltage (Vblock). Consequently, much lower RonS of 0.03 mΩ cm2 and higher Vblock than those of the previously reported diamond SPND were achieved simultaneously. Thus, we elucidated experimentally that the diamond SPND has no trade‐off relationship between RonS and Vblock, and is suitable for low‐loss high‐power switching devices. 相似文献
996.
A transient suppression method for piezoelectric ceramic transducer is presented. By adding some special pedestal pulses to the original transmitted signal, the transient effects in the output of the transducer can be just precisely transmission by use of a narrowband transducer. canceled, thereby achieving the broadband The experimental results show that the transient responses of the sinusoid pulses and coded signals are suppressed successfully and the acoustic waveforms radiated into the surrounding water are improved significantly. 相似文献
997.
This paper presents the planar Fiber Bragg Grating （FBG） hydrophone probe sensing principle, and theoretically and experimentally researches the probe structure sensitivity, the receiving sensitivity frequency response characteristic and the acceleration response property. Planar sheet is made of stainless steel, its thickness is 0.15 mm, its diameter is 15mm, and the length of hollow circular shell is 20 mm. For this size of the structure, the probe structure sensitivity is up to 23 fm/Pa, which is about 7300 times of the value of the bare fiber. The resonance frequency is 6.5 kHz, and the amplitude-frequency curve of the receiving sensitivity response is relatively flat within the frequency range of 100 Hz to 5.5 kHz. The output yielded by one unit acceleration （1m/s2） is equivalent to （2.52 to 3.26 Pa） acoustic pressure acting output. This probe structure is easy to form FBG hydrophone array by multiplexing technique. The research shows that this planar structure not only can form FBG hydrophone probe, but also can constitute optical FBG laser hydrophone probe. The structure can realize different bandwidth, different range acoustic pressure measurement by adjusting the geometrical size of the sheet. 相似文献
998.
999.
During phonation, air pressures act upon the vocal folds to help maintain their oscillation. The air pressures vary dynamically along the medial surface of the vocal folds, although no live human or excised studies have shown how those pressure profiles vary in time. The purpose of this study was to examine time-dependent glottal pressure profiles using a canine hemilarynx approach. The larynx tissue was cut in the midsaggital plane from the top to about 5 mm below the vocal folds. The right half was replaced with a Plexiglas pane with imbedded pressure taps. Simultaneous recordings were made of glottal pressure signals, subglottal pressure, particle velocity, and average airflow at various levels of adduction. The data indicate that the pressures in the glottis (on the Plexiglas) vary both vertically and longitudinally throughout the phonatory cycle. Pressures vary most widely near the location of maximum vibratory amplitude, and can include negative pressures during a portion of the cycle. Pressures anterior and posterior to the maximum amplitude location may have less variation and may remain positive throughout the cycle, giving rise to a new concept called dynamic bidirectional pressure gradients in the glottis. This is an important concept that may relate strongly to tissue health as well as basic oscillatory mechanics. 相似文献
1000.
用伏安法测绘二极管伏安特性的研究 总被引：2，自引：0，他引：2
本提出用伏安法测绘二极管伏安特性曲线的一种电路新接法,用该接法测量时,不需修正即可完全消除电表内阻的影响。 相似文献