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101.
Xiang PH Asanuma S Yamada H Inoue IH Sato H Akoh H Sawa A Ueno K Yuan H Shimotani H Kawasaki M Iwasa Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5822-5827
A prototype Mott transistor, the electric double layer transistor with a strained CaMnO(3) thin film, is fabricated. As predicted by the strain phase diagram of electron-doped manganite films, the device with the compressively strained CaMnO(3) exhibits an immense conductivity modulation upon applying a tiny gate voltage of 2 V. 相似文献
102.
Akihiko Nakajima Takayuki Suzuki Masashi Yoshimi Kenji Yamamoto 《Solar Energy Materials & Solar Cells》1997,48(1-4)
Optical confinement effect of thin-film polycrystalline-Si (poly-Si) solar cell on glass substrate fabricated at low-temperature has been investigated as a function of cell thickness of less than 5 μm. We found that it is possible to fabricate the textured Si thin film in situ on a glass substrate and that the reflectance at long-wavelength light is reduced by surface texturing. Thin-film poly-Si solar cell and a-Si:H/(0.45 μm)/poly-Si (5 μm) tandem solar cell exhibit the efficiency of 8.6% and 12.8%, respectively. The numerical study in terms of the light trapping explains the excellent high short-circuit current density (sc above 27 mA/cm2 at the 4.7 μm thin-film poly-Si solar cell. 相似文献
103.
Benzobisthiazole as Weak Donor for Improved Photovoltaic Performance: Microwave Conductivity Technique Assisted Molecular Engineering 下载免费PDF全文
Masashi Tsuji Akinori Saeki Yoshiko Koizumi Naoto Matsuyama Chakkooth Vijayakumar Shu Seki 《Advanced functional materials》2014,24(1):28-36
New donor–acceptor‐type copolymers comprised of benzobisthiazole (BBTz) as a weak donor rather than acceptor are proposed. This approach can simultaneously lead to deepening the HOMO and LUMO of the polymers with moderate energy offset against fullerene derivatives in bulk heterojunction organic photovoltaics. As a proof‐of‐concept, BBTz‐based random copolymers conjugated with typical electron acceptors: thienopyrroledione (TPD) and benzothiadiazole (BT) based on density functional theory calculations are synthesized. Laser‐flash and Xe‐flash time‐resolved microwave conductivity (TRMC) evaluations of polymer:[6,6]‐phenyl C61 butyric acid methyl ester (PCBM) blends are conducted to screen the feasibility of the copolymers, leading to optimization of processing conditions for photovoltaic device application. According to the TMRC results, alternating BBTz‐BT copolymers are designed, exhibiting extended photoabsorption up to ca. 750 nm, deep HOMO (–5.5 to –5.7 eV), good miscibility with PCBM, and inherent crystalline nature. Moreover, the maximized PCE of 3.8%, the top‐class among BBTz‐based polymers reported so far, is realized in an inverted cell using TiOx and MoOx as the buffer layers. This study opens up opportunities to create low‐bandgap polymers with deep HOMO, and shows how the device‐less TRMC evaluation is of help for decision‐making on judicious molecular design. 相似文献
104.
As the atmospheric electric field always fluctuates, its observed waveforms are very complicated. It is important to detect the characteristic variation from the observed signals and determine its cause. The natural observation method is adequate for analyzing such nonperiodic signals as the atmospheric electric field signals. In this method the aspectum is proposed as the quantity to estimate the instantaneous power. In this study signal processing by the aspectum was applied to signals of atmospheric electric field variation. It was clarified that a strong correlation exists between the instantaneous fluctuations of atmospheric electric field and the wind speed in the convenient meteorological environment. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 155(1): 27–34, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20302 相似文献
105.
Liquid-solid phase de-t-butylation of p-t-butylphenols was carried out over original and dealuminated zeolites to determine the effect of catalyst pore size and acidity on the reaction rate and catalyst fouling rate. The de-t-butylation rate over the original zeolites was mainly dependent upon their micro pore sizes. Although the dealumination by acid leaching decreased strong acid sites, the de-t-butylation rate over dealuminated HY zeolite was higher than that on the original zeolite. The present dealumination is a useful method to prepare an acid catalyst for de-t-butylation in a liquid-solid system. 相似文献
106.
Repeated temperature modulation epitaxy for p-type doping and light-emitting diode based on ZnO. 总被引:27,自引:0,他引:27
Atsushi Tsukazaki Akira Ohtomo Takeyoshi Onuma Makoto Ohtani Takayuki Makino Masatomo Sumiya Keita Ohtani Shigefusa F Chichibu Syunrou Fuke Yusaburou Segawa Hideo Ohno Hideomi Koinuma Masashi Kawasaki 《Nature materials》2005,4(1):42-46
Since the successful demonstration of a blue light-emitting diode (LED), potential materials for making short-wavelength LEDs and diode lasers have been attracting increasing interest as the demands for display, illumination and information storage grow. Zinc oxide has substantial advantages including large exciton binding energy, as demonstrated by efficient excitonic lasing on optical excitation. Several groups have postulated the use of p-type ZnO doped with nitrogen, arsenic or phosphorus, and even p-n junctions. However, the choice of dopant and growth technique remains controversial and the reliability of p-type ZnO is still under debate. If ZnO is ever to produce long-lasting and robust devices, the quality of epitaxial layers has to be improved as has been the protocol in other compound semiconductors. Here we report high-quality undoped films with electron mobility exceeding that in the bulk. We have used a new technique to fabricate p-type ZnO reproducibly. Violet electroluminescence from homostructural p-i-n junctions is demonstrated at room-temperature. 相似文献
107.
Kamilo Feher Masashi Sato 《International Journal of Satellite Communications and Networking》1991,9(3):137-147
A new class of generalized intersymbol-interference and jitter-free (GIJF) modulated signals is introduced. Computer simulation and hardware experimental research results demonstrate that our proposed new generation of signals and modulators leads to significant performance improvements in non-linearly amplified broadband radio systems. For increased power efficiency, non-linear amplification is required in most commercial satellite and terrestrial microwave systems. In particular, we demonstrate that the 3 dB envelope fluctuation of currently used offset raised-cosine overlapped QPSK systems is reduced to 0-5 dB, and that the BER performance is improved by approximately 1 dB. These significant technical performance advantages are expected to lead to more economical implementations of digital transmission systems. 相似文献
108.
Kenji Wada Kazuhiko Hirabayashi Naoki Watanabe Shingo Yamamoto Teruyuki Kondo Take-aki Mitsudo Masashi Inoue 《Topics in Catalysis》2009,52(6-7):693-698
Novel Ti-containing silsesquioxane gel catalysts were prepared by the hydrosilylative condensation of Ti-containing silsesquioxanes together with cubic silsesquioxanes and spherosilicates. The porosity of gels was controlled by changing the composition and the mixing order of the starting materials. Both porous and nonporous gels were found to act as excellent heterogeneous catalysts towards the selective epoxidation of cyclooctene by the use of aqueous hydrogen peroxide as an oxidant. 相似文献
109.
110.
Rahmat Budiarto Masashi Yamada Hidenori Itoh Hirohisa Seki 《Computers & Industrial Engineering》1996,31(3-4):939-943
In many method of the cat's cradle string diagram processing in use today, there is no a strong emphasis on user interaction. This paper discusses a method for constructing cat's cradle string diagram in 2-D. The method uses a string representation and processing in 2-D which preserves the topology characteristics of the string diagram and also uses a small data volume. The inputted string diagram is transformed onto its cat's cradle string diagram by geometric transformation and GA. The method allows the user to interactively construct a cat's cradle string diagram. Three operations are used for constructing cat's cradle diagram, they are pull (over and under), release and exchange. An implemented program executed some shapes of cat's cradle for verifying the method. 相似文献