We have already reported a novel hybrid capacitor multicolor electrochromism (EC) in a single device by introducing a porous electrical double layer counter electrode. In this paper, we investigated the effect of capacitance of counter electrode on the EC properties of anodic EC molecule of phenothiazine derivative. The EC properties of 10-methylphenothiazine (MPT) was examined. The color of MPT changed from colorless to light pink during application of positive potential. ITO particle-modified counter electrodes with various thickness having different capacitance were used to fabricate ECDs. As the electrostatic capacitance of the counter electrode increased, it was found that the color change of the MPT on the working electrode has been obviously vivid. This result directly indicated that the change in electrostatic capacitance played a very important role in ECD with such a structure.
It had been known that the near-infrared is the most transparent optical region. In early 2000' s, near infrared imaging device came into market for various imaging use as the fruit of fiber optics communication development. Various near-infrared laser diodes are also becoming convenient and inexpensive for easy operation and compact device designs. The author's group has developed both fluorescent nanomaterials and various photonic devices for biomedical applications. The transparency of matter is dominated by dielectric constant, in other words, electric dipole moments and their distribution. The responsibility to the constant can be controlled by selecting wavelength. The paper reviews the scientific background of transparency, as well as the developments including fluorescence imaging, photodynamic therapy, thermal imaging, hyperspectral imaging and their biomedical applications.
This paper reviews development of a near-infrared (NIR) broadband light source based on self-assembled InAs quantum dots (QDs) for optical coherence tomography (OCT) applications. OCT is a noninvasive biological and medical profile imaging technique using low coherent interferometry;thus, its imaging quality primarily depends on light source properties. The InAs QDs, a nanoscale semiconductor material, exhibit a broadband spectrum in the NIR region owing to their size and In composite distributions;hence, they are applicable to high-axial-resolution and large-penetration-depth OCT. We developed a QD-based superluminescent diode (QD-SLD) that emits a spectrum spanning approximately 1-1.3µm with a bandwidth of 144nm. In addition, OCT images of test samples were obtained with the QD-SLD, and the images indicated an axial resolution of ∼4µm, which is a significant improvement compared with conventional SLDs (10-15µm). This practical imaging demonstrates the potential of the QD-SLD as a high-axial-resolution OCT light source.
Ultrasonic velocity-change imaging using near-infrared irradiation has potential as a technique for non-invasive evaluation of tissue characteristics. This method is based on the principle that tissue boundaries in the living body can be detected by measuring the change in velocity of the echo pulse. A basic experiment was conducted to examine the effectiveness of this method for the diagnosis of unstable plaque in blood vessels. An experimental device was constructed and applied to a vascular phantom containing a model unstable vascular plaque with lipid core. The wavelength of irradiated light that best identified the lipid area was determined. Ultrasonic velocity-change images displayed areas of lipid core indicating unstable plaque. A compact probe structure was devised that integrated heating and image-acquisition units. Phantom experiments indicated that the compact probe could be applied to carotid artery diagnosis.
The near infrared (NIR) spectroscopy has been applied to analyze the catalyst and adsorbent surfaces. Since H2O molecules were hardly stabilized on the SiO2 surface, the hydrogen bond networks of H2O cluster on the SiO2 surfaces was almost similar to liquid phase H2O. In contrast, H2O molecules were largely stabilized on the TiO2 or Al2O3 surfaces. Thus, the H2O clusters on the TiO2 or Al2O3 surfaces had more complicated hydrogen bond networks as compared to liquid phase H2O. We have further discussed the correlation between the hydrophilic/hydrophobic properties and the surface wettability. Then, the NIR measurements for the SiO2 and cellulose adsorbents grafted with organic functional groups clearly showed the typical absorption bands due to NH2, CH3, and CH2 groups. The alkyl or aminopropyl grafted SiO2 adsorbed drastically smaller amounts of H2O molecules as compared to the pristine SiO2. While the alkyl grafted cellulose showed still hydrophilic surface character because the pristine cellulose was highly hydrophilic. Finally, the NIR spectroscopy enabled the simultaneous analyses of NH3, NH4+ and H2O adsorbed on zeolite surfaces.
This account summarizes our recent attempts to the visualization of the compositional distribution of chemical substances in a small mixer as well as the chlorine ion distribution on the concrete surface by novel Fourier-transformed Near-infrared (NIR) imaging spectroscopic system. The system realized the rapid and direct analysis of the compositional distribution of organic components in a mixer. The quantitative analysis of the three-component mixtures of chemicals was achieved by the measurements within several seconds, while the interpolation of the spectra by zero-filling greatly shorten the acquisition time without significant degradation of data quality. The system was also applicable for the detection of a NIR peak of Friedel's salt immobilized on a concrete surface. Because of its high sensitivity, compact size and the robustness towards the mechanical vibrations the detection of salt-damaged areas at the surface of the hollow bridge's girders was achieved by the outdoor measurements.
This review article looks back on mainly review literature treating smart agriculture, unmanned aerial vehicle remote sensing platforms, vegetation index, proximal (low-altitude) remote sensing with digital cameras. Accordingly bridging the unique spatial and temporal divides that limit current monitoring platforms is key to better environmental systems. Unmanned Aerial Systems have considerable potential to radically improve environmental monitoring. According to a survey of ‘Plant Phenomics' related articles, the most frequently used keywords include “Precision agriculture,”“unmanned aerial vehicle,”“UAV,”“Remote sensing,” and “vegetation index”. Especially vegetation Indices have been utilized for evaluations of global environmental issues. The application of digital cameras to monitor the environment is becoming global and changing the new horizon of data collection. The technique of repeated digital photographs with digital cameras to monitor plant phenology (‘PhenoCams') has increased due to its low-cost investment, reduced-size, easy set-up installation, and the possibility of handling high-resolution near-remote data.
When we read academic papers or reports, we usually read them carefully and critically. Such reading is called active reading. As we can see from the popularization of e-book readers, the support of leisure-based reading such as reading novels or comics has gained a certain level of the success. However, as for active reading where various researches have been conducted since the 1990s, its methodology to support active reading has not determined and it has not gained wide spread use in the market. From recent cognitive experiments, to support active reading, we have gradually found that it is necessary to improve the operability of documents and pages for actions performed during reading. This paper organize previous researches from the perspective of actions performed during reading and introduce our approach which aims to support various actions of active reading.