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941.
Polymer composite comprising polyvinylidene fluoride (PVDF) and potassium hexatitante (K2Ti6O13) was synthesized by solution casting. The effect of K2Ti6O13 on surface, thermal, and electrical properties of polymer composite were investigated. The addition of K2Ti6O13 with polymer leads to thermal degradation and transition of polymer composite from semi-crystalline to amorphous phase. The optimum results of contact angle for different loading wt% of K2Ti6O13 were directly correlated with the surface morphology. Our experimental results confirmed the incorporation of K2Ti6O13 in polymer by SEM micrographs. The evaluated dielectric properties (ε' = 424; tan δ = 2.14 at 130 °C and 100 Hz frequency for 20 wt% loading of K2Ti6O13) for polymer composite are higher in compared to pure polymer. The enhancement in dielectric constant and changing the surface properties of polymer composite can be used for the development of electrochemical storage device applications. 相似文献
942.
A unique structured hollow carbon nanofiber–sulfur composite material (HCF–S) was fabricated and characterized in lithium-sulfur batteries. It is found that a part of spherical sulfur particles are located in the voids formed by the intertwined fibers and the others are confined in hollow channel of the HCF. The high conductive and porous HCF favors the construction of stable three-dimensional conducting network and convenient infiltration of the electrolytes into the cathode. The HCF–S cathode exhibits excellent electrochemical performance in the electrolyte with LiNO3. By contrast, the ionic liquid electrolyte provides insufficient shuttle suppression and weakens ion transport, which leads to poor cycle and rate capability. 相似文献
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We have developed a new numerical ray-tracing approach for LIDAR signal power function computation, in which the light round-trip propagation is analyzed by geometrical optics and a simple experiment is employed to acquire the laser intensity distribution. It is relatively more accurate and flexible than previous methods. We emphatically discuss the relationship between the inclined angle and the dynamic range of detector output signal in biaxial LIDAR system. Results indicate that an appropriate negative angle can compress the signal dynamic range. This technique has been successfully proved by comparison with real measurements. 相似文献
945.
Hidetoshi Shinada 《Optical Review》2016,23(5):765-769
Digital printing systems recorded on films or computer to plates (CTPs) have been required to improve their productivity and image quality. Under the circumstance, a printing technology of the multi-beam laser scanning for the drum capstan system, which is almost the same as optics configuration as the flat bed system, was developed using a newly developed multi-frequency acousto–optic modulator (AOM) as a key device instead of ultra-fast scanning devices toward a main scan direction. The multi-frequency AOM was developed with phased array-type transducers, achieving a wider bandwidth of over 160 MHz. The design consisted of a simultaneous three beams generation with interlace scan to avoid the beat effect by adjacent Doppler-shifted beams, which consequently attained the fastest recording speed of 5.0 mm/s compared with 2.0–3.0 mm/s of existing systems in those days. Furthermore, a couple of critical parameters of the multi-frequency AOM are studied, for example, a treatment of third-order intermodulation and also beat effect in connection with photosensitive media. As a result, the necessity of interlaces scanning to obtain good image quality without beat effect and also to allow a lower laser power to apply is proposed. 相似文献
946.
Toshihiro Kasezawa Hideyoshi Horimai Hiroshi Tabuchi Tsutomu Shimura 《Optical Review》2016,23(6):997-1003
A new photovoltaic generation unit based on the application of holographic technologies called a Holo-Window is proposed in this work. The basic principle and the optical configuration used for the basic experimental unit are described. Suitable fabrication technology for a hologram with the broadband spectrum required to provide the appropriate sunlight capture capability is then discussed. Finally, a laboratory-prototype Holo-Window unit was developed and its performance was evaluated. 相似文献
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