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oe1(光电查) - 科学论文

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出版时间
  • 2018
研究主题
  • electropolymerization
  • polyporphyrin films
  • quartz crystal microbalance method
  • oxygen electroreduction.
应用领域
  • Applied Chemistry
机构单位
  • G.A. Krestov Institute of Solution Chemistry of RAS
  • University Union Nicola Tesla
  • Ivanovo State University of Chemistry and Technology
61 条数据
?? 中文（中国） ▾

  • Dynamics Contributions to the Growth Mechanism of Ga2O3 Thin Film and NWs Enabled by Ag Catalyst

    摘要： In the last few years, interest in the use of gallium oxide (Ga2O3) as a semiconductor for high power/high temperature devices and UV nano-sensors has grown. Ga2O3 has an enormous band gap of 4.8 eV, which makes it well suited for applications in harsh environments. In this work, we explored the effect of Ag thin film as a catalyst to grow gallium oxide. The growth of gallium oxide thin film and nanowires can be achieved by heating and oxidizing pure gallium at high temperatures (~1000 °C) in the presence of trace amounts of oxygen. We present the results of structural, morphological, and elemental characterization of the β-Ga2O3 thin film and nanowires. In addition, we explore and compare the sensing properties of the β-Ga2O3 thin film and nanowires for UV detection. The proposed process can be optimized to a high scale production Ga2O3 nanocrystalline thin film and nanowires. By using Ag thin film as a catalyst, we can control the growth parameters to obtain either nanocrystalline thin film or nanowires.

    关键词： Ga2O3,thermal oxidation,nanowires,thin film,silver catalyst,quartz

    更新于2025-09-11 14:15:04

  • Effectiveness of Light Source on Detecting Thin Film Transistor

    摘要： Light sources tend to affect images captured in any automatic optical inspection (AOI) system. In this study, the effectiveness of metal-halide lamps, quartz-halogen lamps, and LEDs as the light sources in AOI systems for the detection of the third and fourth layers electrodes of thin-?lm-transistor liquid crystal displays (TFT-LCDs) is examined experimentally. The results show that the performance of LEDs is generally comparable or better than that of metal-halide and quartz-halogen lamps. The best optical performance is by the blue LED due to its spectrum compatibility with the time-delay-integration charged-coupled device (TDI CCD) sensor and its better spatial resolution. The images revealed by the blue LED are sharper and more distinctive. Since current LEDs are more energy ef?cient and environmentally friendly, using LEDs as the light source for AOI is very bene?cial. As the blue LED performs the best, it should be adopted for AOI using TDI CCD sensors.

    关键词： TFT-LCD,blue LED,spectrum,quartz-halogen lamp,metal-halide lamp

    更新于2025-09-10 09:29:36

  • Nucleation mechanism of metal-vapor atoms on photochromic diarylethene surface with a low glass transition temperature

    摘要： Metal pattern formation on organic surfaces is essential in organic electronics. Selective metal-vapor deposition using photochromic diarylethene (DAE) is a promising method to prepare ?ne metal patterns by maskless evaporation. Metal-vapor atoms are adsorbed, di?used, and then desorbed from the colorless surface with a low glass transition temperature. We, however, found that metal deposition started at a speci?c time (deposition-threshold time, tth) even on the colorless surface by continuous evaporation. tth was investigated using a quartz crystal microbalance. We elucidated that metal-nucleation sites were generated by chemical reactions between metal atoms and surface DAE molecules. The number of nucleation sites increases during metal evaporation and when the sites are located in the di?usion range of surface metal atoms, metal-atom nucleation for ?lm-formation starts. This is the origin of tth. This result would provide important knowledge for the preparation of electrodes for organic devices based on selective metal-vapor deposition.

    关键词： organic electronics,nucleation mechanism,photochromic diarylethene,quartz crystal microbalance,metal-vapor deposition

    更新于2025-09-10 09:29:36

  • On the possibility of the electron-beam welding of quartz glasses by a forevacuum plasma electron source

    摘要： The article demonstrates a principle possibility of the electron-beam welding of high-temperature quartz glasses by a plasma electron source operating in the forevacuum range of pressure of 10-50 Pa. We studied the dependence of the composition of the gas atmosphere in the vacuum chamber on the heating temperature of the weld seam. It is shown that the optimal temperature of the weld seam for melting and minimum mass entrainment from the molten pool is 1300 to 1400 0C. We determined the welding regime for cylindrical tubes and rods that provides high seam strength, reaching 90-95% of the original strength of quartz glass.

    关键词： forevacuum range of pressure,electron-beam welding,plasma electron source,quartz glass

    更新于2025-09-10 09:29:36

  • Dynamic relaxation oscillations in a nonlinearly driven quartz crystal

    摘要： We demonstrate thermo-mechanical relaxation oscillations in a strongly driven quartz crystal. Dynamic bifurcation leads to two stable oscillation states with a distinct electrical impedance. Slow Joule-heating, which shifts the susceptibility of the crystal, provides a feedback that leads to thermally induced oscillations in which the amplitude of the crystal is modulated by a relaxation cycle. The frequency of the relaxation cycle is roughly a million times lower than the resonance frequency of the crystal, and it can be adjusted by the detuning from the critical point for dynamic bifurcation. The experimental observations are reproduced by a simple model that takes into account the slow dynamics of the system.

    关键词： dynamic bifurcation,Joule-heating,feedback,thermo-mechanical relaxation oscillations,quartz crystal

    更新于2025-09-10 09:29:36

  • Development of Process for Fast Plasma-Chemical Through Etching of Single-Crystal Quartz in SF6/O2 Gas Mixture

    摘要： Process for deep plasma-chemical etching of single-crystal quartz plates in a SF6/O2 gas mixture was developed. The method of scienti? c experiment design based on the Taguchi matrix technique was used to rank basic technological parameters (bias voltage applied to the substrate holder, output power of the high-frequency generator, oxygen ? ow rate, and position of the substrate holder relative to the lower edge of the discharge chamber) as regards their in? uence on the etching rate. The ranking results were used to optimize the plasma-chemical etching process and perform a control experiment on through etching of windows with large linear dimensions (3 × 10 mm) in a single-crystal quartz plate (z-cut) with thickness of 369 μm.

    关键词： single-crystal quartz,plasma-chemical etching,sulfur hexa? uoride,Taguchi method

    更新于2025-09-10 09:29:36

  • A 400-GHz Wideband High-Gain Quartz-Based Single-Layered Folded Reflectarray Antenna for Terahertz Applications

    摘要： Compact high-gain antennas are highly desired in the high speed terahertz (THz) wireless system, especially for the space limited application such as the high speed inter-link inside the high density wireless communication base station. To this end, a 400-GHz folded reflectarray (FRA) antenna with high gain, high aperture efficiency and compact profile is proposed in this paper. It is composed of a feed source, a single-layered reflectarray using a lithography process on quartz, and a wire-grid polarizer implemented by the printed-circuit-board (PCB) technology. A 3-D printed fixture is used to assemble all parts together. In order to design accurately the THz electromagnetic properties of the supporting dielectric materials are extracted by using a THz time-domain spectrometer system. Then, a single-layered phasing element, made up of a pair of orthogonally I-shaped structures with an open square ring, is proposed and designed based on the extracted material characteristics. Both phase compensation and polarization conversion can be realized by the proposed unit cell. A reflectarray is designed by using the proposed phasing element with the conventional array synthesizing theory, and a THz grid polarizer is designed with strips on a 0.127 mm Taconic TLY-5 substrate. The THz grid is placed in front of the THz feed and the reflectarray, which is fully reflective to the feed and transparent to the reflectarray. All components of the FRA antenna have been fabricated and assembled. Experiments show that the FRA prototype has a peak gain of 33.66 dBi at 400 GHz with an aperture efficiency of 33.65%, and a 3-dB gain bandwidth of 16% (357-421 GHz).

    关键词： terahertz,3-D printing,high-gain,material characteristics,quartz substrate,single-layer,Folded reflectarray antenna,THz time-domain spectrometer

    更新于2025-09-10 09:29:36

  • Detection of Benzene and Volatile Aromatic Compounds by Molecularly Imprinted Polymer Coated Quartz Crystal Microbalance Sensor

    摘要： The detection of benzene and its analogues are important but difficult without using expensive extremely analytical instruments. The present work reports the detection of aromatic hydrocarbons like benzene, toluene and isomers of xylene using quartz crystal microbalance (QCM) sensor. The surface of a silver-coated quartz crystal was coated with a simple solution drop coating method and thermally polymerized in an inert atmosphere for the formation of the sensing film. The polymer was synthesized by copolymerization of the optimum ratio of styrene, divinylbenzene and tung oil at 90°C with template. 1, 2, 3 trimethoxybenzene as template performed most efficiently for all the hydrocarbons. Linear calibration curves were observed for all the vapors in the concentration range between approximately as 1.645 to 2.605 Hz/ppm. For benzene, the sensitivity is 2.605 Hz /ppm which is the highest amongst the reported literature. Thus minimum concentration of benzene that can be detected is 0.98 ppm. The molecularly imprinted polymer structure and surface morphology were analyzed by FTIR spectroscopy, FESEM and AFM. The sensitivity of detection of aromatic molecule in this work by the molecularly imprinted polymer film is found to be the best amongst the reported literatures.

    关键词： molecular imprinting technique,thermal polymerization,vegetable oil,Quartz Crystal Microbalance (QCM),aromatic hydrocarbons

    更新于2025-09-10 09:29:36

  • Reply to the comments by Madsen & Liu on “Late quaternary OSL chronologies from the Qinghai Lake (NE Tibetan Plateau): Inter-comparison of quartz and K-feldspar ages to assess the pre-depositional bleaching”

    摘要： In response to the comment of Madsen and Liu (2018), we explain why our quartz optically stimulated luminescence (OSL) ages showing the early MIS 3 lake highstand are robust. We also demonstrate that the difference in the age estimates between ours (Long et al., 2018) and other studies should be attributed to contrasting equivalent dose (De) values, rather than water contents (hence the dose rate) which was claimed by Madsen and Liu (2018).

    关键词： K-feldspar age,Qinghai Lake,Lake highstand,quartz OSL age

    更新于2025-09-09 09:28:46

  • Nano-layered-structure interface between Sn-Ti alloy and quartz glass for hermetic seals

    摘要： The interface structure between Sn-Ti alloy and quartz glass was investigated by transmission electron microscope. The results show that the interface is continuous and dense and has a nano-layered-structure with thickness of several tens of nanometer without holes and cracks. The interface is divided into two layers. One is the TiO2 layer with a thickness of about 2 nm locates near Sn-Ti alloy, and the other is a multiphase structure layer near the quartz glass composed of nanocrystalline TiSi2, Ti5Si3 and TiO2.

    关键词： Interface,Quartz glass,Microstructure,Sn-Ti alloy

    更新于2025-09-09 09:28:46