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41.
Recently, absorption-sensitive surface plasmon resonance (SPR) techniques have attracted much attention. SPR near-infrared spectroscopy (SPR-NIRS) based on the Kretschmann configuration is one of the techniques for absorption enhancement. The enhanced spectrum obtained by SPR-NIRS basically corresponds to the measurement of an NIR absorption spectrum with a very short path length. However, the path length cannot be applied for Lambert's law due to the enhanced evanescent field. A direct determination of the penetration depth of the evanescent field is carried out via NIR absorptions enhanced by the off-resonance of surface plasmons, which is a principle of SPR-NIRS. The signal intensities of the enhanced NIR spectra of micrometer-thick polymer films having various thicknesses are compared with the classic theory of penetration depth. It is confirmed that the effective depth of the SPR-NIRS measurement can be expressed by the classic theory of penetration depth of the evanescent field proposed by Harrick. 相似文献
42.
Akifumi Matsuda Shusaku Akiba Takahiro Watanabe Yoshitaka Kitamoto Hitoshi Kawaji Kouji Koyama 《Thin solid films》2008,516(12):3873-3876
The ferromagnetic epitaxial Ni (111) thin film on the oxide substrate could be obtained by an epitaxy method, employing pulsed laser deposition (PLD) of epitaxial NiO (111) film on the sapphire (α-Al2O3) substrate and successive hydrogen reduction. The epitaxial NiO (111) film was deposited on the sapphire (0001) substrate at room temperature by PLD, and was reduced into the Ni epitaxial film by annealing (300 °C to 700 °C) in the hydrogen atmosphere, suggesting the possible formation of epitaxial [Ni metal/α-Al2O3] multilayer. The epitaxy of Ni film was proved by ex situ X-ray diffraction. The ferromagnetic anisotropy of the epitaxial Ni film was examined by superconducting quantum interference magnetometry. 相似文献
43.
Takizawa K Takahashi A Tokuhashi K Kondo S Sekiya A 《Journal of hazardous materials》2008,155(1-2):144-152
Burning velocity measurements of nitrogen-containing compounds, i.e., ammonia (NH3), methylamine (CH3NH2), ethylamine (C2H5NH2), and propylamine (C3H7NH2), were carried out to assess the flammability of potential natural refrigerants. The spherical-vessel (SV) method was used to measure the burning velocity over a wide range of sample and air concentrations. In addition, flame propagation was directly observed by the schlieren photography method, which showed that the spherical flame model was applicable to flames with a burning velocity higher than approximately 5 cm s−1. For CH3NH2, the nozzle burner method was also used to confirm the validity of the results obtained by closed vessel methods. We obtained maximum burning velocities (Su0,max) of 7.2, 24.7, 26.9, and 28.3 cm s−1 for NH3, CH3NH2, C2H5NH2, and C3H7NH2, respectively. It was noted that the burning velocities of NH3 and CH3NH2 were as high as those of the typical hydrofluorocarbon refrigerants difluoromethane (HFC-32, Su0,max = 6.7 cm s−1) and 1,1-difluoroethane (HFC-152a, Su0,max = 23.6 cm s−1), respectively. The burning velocities were compared with those of the parent alkanes, and it was found that introducing an NH2 group into hydrocarbon molecules decreases their burning velocity. 相似文献
44.
用于空气中水蒸气吸-脱附的微孔泡沫炭制备研究 总被引:1,自引:0,他引:1
以蜜胺泡沫体为模板,采用氟化聚酰业胺制备了微孔泡沫炭.测定了其对环境中水气的吸附/脱附行为,发现:泡沫炭在空气中400℃活化1 h,可以提高其对水气的吸附能力.与活化前相比,对水气的吸附量几乎高达3倍,尽管其微孔容积仅增大了1.5倍.对环境水气中的可逆吸附率与微孔容积成线性关系,微孔容积为0.75mL/g的泡沫炭,其水气吸附率约为质最分数40%. 相似文献
45.
Masahiro Maeda Kotaro Kushiyama 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》2005,20(2):1
In Tokyo Metropolis, the rehabilitation and renewal of sewer systems is an urgent issue due to the aged sewers and increases in wastewater and stormwater runoff. In such urban area, shield tunneling confronts various problems, such as high construction costs, adverse effects on living environments, and densely used surface and underground spaces. To solve these problems, the authors developed a new shield tunneling method, which is called the “compact shield” method. This paper describes the concepts used for the construction of shield sewer tunnels without inner linings and an overview of the segments and a shield machine that were newly developed. 相似文献
46.
An accurate and stable multiphase moving particle semi‐implicit method based on a corrective matrix for all particle interaction models 下载免费PDF全文
Guangtao Duan Seiichi Koshizuka Akifumi Yamaji Bin Chen Xin Li Tasuku Tamai 《International journal for numerical methods in engineering》2018,115(10):1287-1314
The Lagrangian moving particle semi‐implicit (MPS) method has potential to simulate free‐surface and multiphase flows. However, the chaotic distribution of particles can decrease accuracy and reliability in the conventional MPS method. In this study, a new Laplacian model is proposed by removing the errors associated with first‐order partial derivatives based on a corrected matrix. Therefore, a corrective matrix is applied to all the MPS discretization models to enhance computational accuracy. Then, the developed corrected models are coupled into our previous multiphase MPS methods. Separate stabilizing strategies are developed for internal and free‐surface particles. Specifically, particle shifting is applied to internal particles. Meanwhile, a conservative pressure gradient model and a modified optimized particle shifting scheme are applied to free‐surface particles to produce the required adjustments in surface normal and tangent directions, respectively. The simulations of a multifluid pressure oscillation flow and a bubble rising flow demonstrate the accuracy improvements of the corrective matrix. The elliptical drop deformation demonstrates the stability/accuracy improvement of the present stabilizing strategies at free surface. Finally, a turbulent multiphase flow with complicated interface fragmentation and coalescence is simulated to demonstrate the capability of the developed method. 相似文献
47.
Y Morisawa N Higashi K Takaba N Kariyama T Goto A Ikehata Y Ozaki 《The Review of scientific instruments》2012,83(7):073103
A far-ultraviolet transient absorption spectrometer based on time-resolved attenuated total reflectance (ATR) has been developed and tested for aqueous solutions of phenol and tryptophan in the region 170-185 nm. In this region, a stable tunable laser was not available, and therefore, white light from a laser-driven Xe lamp source was used. The time resolution, which was determined by the time response of a continuous light detector, was 40 ns. A new ATR cell where a sample liquid is exchanged continuously by a flow system was designed to reduce efficiently the stray light from the excitation light. We have tested the performance of the instrument by using aqueous solutions of phenol and tryptophan, whose photochemistry is already well known. Phenol and tryptophan have very strong absorptions due to a π-π? transition near 180 nm. Even for dilute solutions (10(-3) mol dm(-3)), we could observe decreases in their concentrations due to photochemistry that occurred upon their irradiation with a fourth harmonic generation laser pulse produced by an Nd:YAG laser. The sensitivity of the spectrometer was about 10(-4) abs, which corresponded to a concentration variation of 10(-3) mol dm(-3) for phenol and tryptophan. 相似文献
48.
Koji Murata Kosuke Murano Issei Watanabe Akifumi Kasamatsu Toshiyuki Tanaka Yasuaki Monnai 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(2):210-221
We experimentally demonstrate see-through detection and 3D reconstruction using terahertz leaky-wave radar based on sparse signal processing. The application of terahertz waves to radar has received increasing attention in recent years for its potential to high-resolution and see-through detection. Among others, the implementation using a leaky-wave antenna is promising for compact system integration with beam steering capability based on frequency sweep. However, the use of a leaky-wave antenna poses a challenge on signal processing. Since a leaky-wave antenna combines the entire signal captured by each part of the aperture into a single output, the conventional array signal processing assuming access to a respective antenna element is not applicable. In this paper, we apply an iterative recovery algorithm “CoSaMP” to signals acquired with terahertz leaky-wave radar for clutter mitigation and aperture synthesis. We firstly demonstrate see-through detection of target location even when the radar is covered with an opaque screen, and therefore, the radar signal is disturbed by clutter. Furthermore, leveraging the robustness of the algorithm against noise, we also demonstrate 3D reconstruction of distributed targets by synthesizing signals collected from different orientations. The proposed approach will contribute to the smart implementation of terahertz leaky-wave radar. 相似文献
49.
50.
Holographic polymer dispersed liquid crystal (HPDLC) memory is fabricated by a photoinduced phase separation comprised of polymer and liquid crystal (LC) phases using laser light interference exposures. The anisotropic diffraction induced by the alignment of LC in the periodic structure of the HPDLC memory is applied to reconstruct the configuration contexts for the optically reconfigurable gate arrays. Optical reconfiguration for various circuits under parallel programmability is implemented by switching the polarization state of incident light on the HPDLC memory using a spatial light modulator. 相似文献