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排序方式: 共有990条查询结果,搜索用时 125 毫秒
91.
92.
Tsuyoshi Saotome Hansang Kim David Lashmore H. Thomas Hahn 《Bulletin of Materials Science》2011,34(4):615-622
We describe in this paper a transparent conducting film (TCF). It is a fibrous layer of multiwalled carbon nanotubes (MWNTs),
labeled a dilute CNT mat, that was prepared and unidirectionally stretched to improve both the optical and electrical properties.
After stretching by 80% strain, transmittance at 550 nm wavelength was improved by 37% and sheet resistance was reduced to
71% of the original value. The improvement of the transmittance can be explained by increased area of the CNT mat after stretch,
and the reduced sheet resistance can be explained by increased density of the CNT alignment in lateral direction due to contraction.
Based on the microscopic observation before and after stretch, models to describe the phenomena are proposed. By further expanding
on this method, it may be possible to obtain a transparent conducting carbon nanotube film which is crack-resistant for solar
cell applications. 相似文献
93.
Kazuya Nakata Keizo Udagawa Tsuyoshi Ochiai Hideki Sakai Taketoshi Murakami Masahiko Abe Akira Fujishima 《Materials Chemistry and Physics》2011
TiO2-polydimethylsiloxane (TiO2-PDMS) composite films are prepared using the sol–gel method from a Ti(OBu)4–benzoylacetone solution containing PDMS. The prepared films are cured by irradiation with ultraviolet (UV) light. Structural changes in the films after UV irradiation are confirmed by UV–vis absorption experiments, which show that an absorption band characteristic of the benzoylacetonate chelate rings disappears. This finding is ascribed to structural changes associated with the dissociation of the chelate rings. The IR spectra of the thin films exhibit a broad absorption band after UV irradiation, indicating that a Ti–O–Ti network forms in the thin film. Contact angles are measured for the TiO2-PDMS thin films, showing wettability conversion from hydrophobic to superhydrophilic states by irradiation with oxygen plasma for 1 s. This phenomenon is explained by XPS experiments which reveal that the number of carbon atoms decreases, whereas the number of oxygen atoms increases on the surface of the TiO2-PDMS composite films. Finally, hydrophobic–superhydrophilic patterns are fabricated based on a patterned TiO2-PDMS composite film. The film displays a rapid change to superhydrophilicity over the whole film surface upon plasma irradiation for 1 s, which means that the wettability patterns are rapidly erasable. 相似文献
94.
Ito K Kawase T Sammoto H Gomi K Kariyama M Miyake T 《Journal of Bioscience and Bioengineering》2011,111(3):300-305
Solid-state fermentation (SSF) has attracted a lot of interest for carrying out high-level protein production in filamentous fungi. However, it has problems such as the fermentation heat generated during the culture in addition to the reduced mobility of substances. These conditions lead to a nonuniform state in the culture substrate and result in low reproducibility. We constructed a non-airflow box (NAB) with a moisture permeable fluoropolymer membrane, thereby making it possible to control and maintain uniform and optimal conditions in the substrate. For the NAB culture in Aspergillus oryzae, temperature and water content on/in the whole substrate were more consistent than for a traditional tray box (TB) culture. Total weight after the culture remained constant and dry conditions could be achieved during the culture. These data demonstrate the possibility of growing a uniform culture of the whole substrate for SSF. The NAB is advantageous because it allows for the control of exact temperature and water content in the substrate during the culture by allowing vapor with latent heat to dissipate out of the box. In addition, several enzymes in the NAB culture exhibited higher production levels than in the TB culture. We believe that culturing in the constructed NAB could become a standard technique for commercial SSF. 相似文献
95.
Riza Muhida Minwon Park Mohammed Dakkak Kenji Matsuura Akira Tsuyoshi Masakazu Michira 《Solar Energy Materials & Solar Cells》2003,75(3-4):697-706
Processes to produce hydrogen from solar photovoltaic (PV)-powered water electrolysis using solid polymer electrolysis (SPE) are reported. An alternative control of maximum power point tracking (MPPT) in the PV-SPE system based on the maximum current searching methods has been designed and implemented.Based on the characteristics of voltage–current and theoretical analysis of SPE, it can be shown that the tracking of the maximum current output of DC–DC converter in SPE side will track the MPPT of photovoltaic panel simultaneously.This method uses a proportional integrator controller to control the duty factor of DC–DC converter with pulse-width modulator (PWM).The MPPT performance and hydrogen production performance of this method have been evaluated and discussed based on the results of the experiment. 相似文献
96.
Ghosts and flares are well-known problems that are caused by reflections from lens surfaces when we take photographs. It is more difficult to prevent such stray light in a digital camera than in a film camera because of high reflectance from the low-pass filter and diffraction from the image sensor. To prevent such stray light, we introduce an ultralow refractive index layer into the antireflective (AR) coatings. We used the solgel method to form porous fluoride layers with ultralow refractive indices, and we succeeded in developing a unique process to form AR coatings with superior performance. 相似文献
97.
Dhinesh Babu Velusamy Richard Hahnkee Kim Kazuto Takaishi Tsuyoshi Muto Daisuke Hashizume Soyoon Lee Masanobu Uchiyama Tetsuya Aoyama Jean-Charles Ribierre Cheolmin Park 《Organic Electronics》2014,15(11):2719-2727
Polymer ferroelectric-gate field effect transistors (Fe-FETs) employing ferroelectric polymer thin films as gate insulators are highly attractive as a next-generation non-volatile memory. For minimizing gate leakage current of a device which arises from electrically defective ferroelectric polymer layer in particular at low operation voltage, the materials design of interlayers between the ferroelectric insulator and gate electrode is essential. Here, we introduce a new solution-processed interlayer of conductive reduced graphene oxides (rGOs) modified with a conjugated block copolymer, poly(styrene-block-paraphenylene) (PS-b-PPP). A FeFET with a solution-processed p-type oligomeric semiconducting channel and ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) insulator exhibited characteristic source–drain current hysteresis arising from ferroelectric polarization switching of a PVDF-TrFE insulator. Our PS-b-PPP modified rGOs (PMrGOs) with conductive moieties embedded in insulating polymer matrix not only significantly reduced the gate leakage current but also efficiently lowered operation voltage of the device. In consequence, the device showed large memory gate voltage window and high ON/OFF source–drain current ratio with excellent data retention and read/write cycle endurance. Furthermore, our PMrGOs interlayers were successfully employed to FeFETs fabricated on mechanically flexible substrates with promising non-volatile memory performance under repetitive bending deformation. 相似文献
98.
A levitation method has been introduced which uses 8-shape levitation coils arranged on the vertical surface of the guideway. These coils can act as a guidance means as well as the levitation means. The characteristics of this system are examined using numerical examples and experimental data. The cables connecting right and left coils are not connected to a high-voltage power source unlike the usual guidance system which is combined with propulsion. Thus the electric insulation of the cables is not a problem at present. Numerical examples show that the levitation characteristics of the combined levitation and guidance system are almost the same as in the system without the guidance function, and that it attains reduced running resistance with necessary guidance stiffness obtained. A test run was done at Miyazaki Test Line equipped with coils of this type arranged about 120 m, and the results show stable running and balanced displacement which agrees with calculated values. 相似文献
99.
Tadashi Hirayama Jun Oyama Tsuyoshi Higuchi Takashi Abe 《Electrical Engineering in Japan》2008,165(1):82-90
This paper presents the principle and basic characteristics of a novel linear synchronous motor based on “half‐wave rectified self excitation principle.” The field winding is short circuited through a diode and the armature winding consists of conventional three‐phase windings. If the amplitude of the balance three‐phase currents is modulated by an alternating wave with bias frequency, the produced magnetomotive force pulsates at the bias frequency and moves at the synchronous velocity. This pulsating magnetomotive force induces the electromotive force with a bias frequency in the field winding. The field excitation is obtained by rectifying the electromotive force with the diode in the field winding. In this paper, the authors design and build an experimental machine and confirm its basic characteristics. They also deduce the performance equations and investigate the thrust ripple reduction. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(1): 82–90, 2008; Published online in Wiley InterScience ( www. interscience.wiley.com ). DOI 10.1002/eej.20684 相似文献
100.
Kiyoshi Dowaki Tsuyoshi Ohta Yasukazu Kasahara Mitsuo Kameyama Koji Sakawaki Shunsuke Mori 《Renewable Energy》2007,32(1):80-94
Recently, in Japan, recycling technologies have been developed using waste biomass material. Waste biomass is traded in the waste materials market between users and a third-party, who receives a fee for processing them. This study is an environmental and economic analysis of a biomass energy system, which can produce hydrogen fuel for fuel cells (purity of 99.99%) as an example of an environmental business model. The experimental apparatus was made based on the moving-bed gasifier by the German company, DM2 Inc., and the hydrogen gas yield was measured. Finally, the economic viability of the future hydrogen business was estimated.The experimental results obtained gave the gas concentration of 57.5% in a Steam/Carbon ratio of 1.40 at 900 °C.Assuming the plant scale of 10 t/d, the production amount of hydrogen gas would be 21.3 kg/h. Based on the law concerning waste processing in Japan, a sizeable amount of waste biomass could be expected. Therefore, if the processing fee which is paid to the group (contractor) ranges between 5.0 and 10.0 $/t, and if the whole investment cost is 6 million dollars and the depreciation period is 15 years, the bio-hydrogen production cost using the experimental data would be 5.75–7.86 $/kg-H2 without receiving related subsidies. In a one-third grant proportion, the cost would become 4.60–6.72 $/kg-H2. 相似文献