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241.
A novel sol–gel process was developed for preparing thin films and fine powders of lanthanum manganite (LaMnO3 ) with perovskite-type structure. Lanthanum and manganese acetylacetonate powders could be easily dissolved in a mixed solution of methyl alcohol and ethylene glycol (or methyl alcohol and propionic acid) to give a spinnable organic solution as a starting material. Pretreatment of a substrate by poly(vinyl alcohol) (PVA) aqueous solution, a gel former, made it possible to deposit a thin film as well as to lower the sintering temperature. 相似文献
242.
Since a general flat hologram has a limited viewable area, we usually cannot see the other side of a reconstructed object. There are some holograms that can solve this problem. A cylindrical hologram is well known to be viewable in 360 deg. Most cylindrical holograms are optical holograms, but there are few reports of computer-generated cylindrical holograms. The lack of computer-generated cylindrical holograms is because the spatial resolution of output devices is not great enough; therefore, we have to make a large hologram or use a small object to fulfill the sampling theorem. In addition, in calculating the large fringe, the calculation amount increases in proportion to the hologram size. Therefore, we propose what we believe to be a new calculation method for fast calculation. Then, we print these fringes with our prototype fringe printer. As a result, we obtain a good reconstructed image from a computer-generated cylindrical hologram. 相似文献
243.
Hideaki Araki Aya Mikaduki Yuki Kubo Tatsuhiro Sato Kazuo Jimbo Win Shwe Maw Hironori Katagiri Makoto Yamazaki Koichiro Oishi Akiko Takeuchi 《Thin solid films》2008,517(4):1457-1460
Stacked precursors of Cu, Sn, and Zn were fabricated on glass/Mo substrates by electron beam evaporation. Six kinds of precursors with different stacking sequences were prepared by sequential evaporation of Cu, Sn, and Zn with substrate heating. The precursors were sulfurized at temperatures of 560 °C for 2 h in an atmosphere of N2 + sulfur vapor to fabricate Cu2ZnSnS4 (CZTS) thin films for solar cells. The sulfurized films exhibited X-ray diffraction peaks attributable to CZTS. Solar cells using CZTS thin films prepared from six kinds of precursors were fabricated. As a result, the solar cell using a CZTS thin film produced by sulfurization of the Mo/Zn/Cu/Sn precursor exhibited an open-circuit voltage of 478 mV, a short-circuit current of 9.78 mA/cm2, a fill factor of 0.38, and a conversion efficiency of 1.79%. 相似文献
244.
Katsuya Abe Yohei Nagasaka Takahiro Kida Tomohiko Yamakami Rinpei Hayashibe Kiichi Kamimura 《Thin solid films》2008,516(5):637-640
SiC films were synthesized by hot-wire chemical vapor deposition using a tungsten filament and a gas mixture of SiF4 and CH4. The etching of the substrate instead of the film growth occurred on the samples prepared using only source gases without H2 dilution. The atomic or molecular hydrogen was believed to control the density of radicals containing F in a gas phase or on a growth surface. Polycrystalline 3C-SiC(111) films were successfully obtained at substrate temperatures lower than 500 °C by using H2 dilution. The growth mode limited by source-gas supply was found to be important to obtain polycrystalline SiC films. The SiC film grown at higher deposition pressure was amorphous and contained no Si-Hx bonds but 6% fluorine. In SiF4/CH4/H2 system, the radicals containing F are considered to play very important roles in the reactions both on a growth surface and in a gas-phase. 相似文献
245.
White-light-emitting materials have attracted considerable attention because of their applications, such as large-surface emitting devices. Inorganic phosphor films are expected to be applied to these devices because of good chemical stability; however, a substantial reduction of fabrication temperature is required for future industrial uses such as lighting materials fabricated onto flexible organic substrates. Here we show the optical properties of white-light-emitting metavanadate phosphors, AVO3 (A: K, Rb and Cs), and we report a new direct fabrication process for RbVO3 films onto flexible polyethylene terephthalate (PET) substrates by means of a vacuum ultraviolet irradiation using an excimer lamp. In addition, the (Ca,Sr,Pr)TiO3/a-Al2O3/RbVO3/PET heterostructure prepared by an excimer-laser-assisted metal-organic deposition process has demonstrated the possibility of colour modification for RbVO3 films on PET. Our findings suggest new possibilities for further development of large-surface emitting lighting devices. 相似文献
246.
Shingo Urate Hiromichi Wakui Kengo Azushima Takahiro Yamaji Toru Suzuki Eriko Abe Shohei Tanaka Shinya Taguchi Shunichiro Tsukamoto Sho Kinguchi Kazushi Uneda Tomohiko Kanaoka Yoshitoshi Atobe Kengo Funakoshi Akio Yamashita Kouichi Tamura 《International journal of molecular sciences》2021,22(22)
The kidney is one of the most susceptible organs to age-related impairments. Generally, renal aging is accompanied by renal fibrosis, which is the final common pathway of chronic kidney diseases. Aristolochic acid (AA), a nephrotoxic agent, causes AA nephropathy (AAN), which is characterized by progressive renal fibrosis and functional decline. Although renal fibrosis is associated with renal aging, whether AA induces renal aging remains unclear. The aim of the present study is to investigate the potential use of AAN as a model of renal aging. Here, we examined senescence-related factors in AAN models by chronically administering AA to C57BL/6 mice. Compared with controls, the AA group demonstrated aging kidney phenotypes, such as renal atrophy, renal functional decline, and tubulointerstitial fibrosis. Additionally, AA promoted cellular senescence specifically in the kidneys, and increased renal p16 mRNA expression and senescence-associated β-galactosidase activity. Furthermore, AA-treated mice exhibited proximal tubular mitochondrial abnormalities, as well as reactive oxygen species accumulation. Klotho, an antiaging gene, was also significantly decreased in the kidneys of AA-treated mice. Collectively, the results of the present study indicate that AA alters senescence-related factors, and that renal fibrosis is closely related to renal aging. 相似文献
247.
Machine Learning - Clustering is a fundamental task in data analysis, and spectral clustering has been recognized as a promising approach to it. Given a graph describing the relationship between... 相似文献
248.
Non‐isothermal crystallization behavior of stereo diblock polylactides with relatively short poly(d‐lactide) segments from the melt 下载免费PDF全文
Stereo diblock polylactides (SDB‐PLAs) composed of relatively short poly(d ‐lactide) (PDLA) segments and relatively long poly(l ‐lactide) (PLLA) segments were synthesized to have a wide number‐average molecular weight (Mn) range of 2.5 × 104–2.0 × 105 g mol?1 and d ‐lactyl unit content of 0.9–38.6%. The effects of incorporated short PDLA segments (Mn = 2.0 × 103–7.7 × 103 g mol?1) on crystallization behavior of the SDB‐PLAs were first investigated during heating after complete melting and quenching or during slow cooling after complete melting. Stereocomplex (SC) crystallites can be formed at d ‐lactyl unit content as low as 4.3 and 5.8% for heating and slow cooling, respectively, and for Mn of PDLA segments as low as 2.0 × 103 and 3.5 × 103 g mol?1, respectively. With decreasing Mn and increasing d ‐lactyl unit content, the cold crystallization temperature during heating decreased and the crystallization temperature during slow cooling increased. With increasing d ‐lactyl unit content, the melting enthalpy (ΔHm) of SC crystallites during heating and the crystallinity (Xc) of SC crystallites after slow cooling increased, whereas ΔHm of PLLA homo‐crystallites during heating and Xc of PLLA homo‐crystallites after slow cooling decreased. The total ΔHm of SC crystallites and PLLA homo‐crystallites during heating and the total Xc after slow cooling became a minimum at d ‐lactyl unit content of 10–15% and gave a maximum at d ‐lactyl unit content of 0%. Despite the accelerated crystallization of some of SDB‐PLAs, the low values of total ΔHm and Xc at d ‐lactyl unit content of 10–15% are attributable to the formation of two crystalline species of SC crystallites and PLLA homo‐crystallites. 相似文献
249.
250.
The ability for a product or a service to meet customer needs and requirements efficiently before its market launch is a key-point in design and development activities. Quality Function Deployment (QFD) represents one of the most powerful design methods to achieve such a goal. This study investigates the QFD-based methods proposed in the last two decades, whose use in different ambits of Design for X (DfX) is reported to be effective. We selected most common QFD-based methods, analyzing how designers can implement and coordinate them in design activities effectively throughout their application to an identical case study. 相似文献