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21.
The microstructure of Cu interconnections fabricated by high-pressure annealing was evaluated using a field emission scanning
electron microscope/electron backscatter diffraction pattern (FE-SEM/EBSP) technique, and the results are compared with as-deposited
and normally annealed Cu films. The results show some grains extending from the bulk field to the via regions in the case
of the high-pressure annealed Cu films. The existence of via holes was also observed, in which all grains were (111) oriented.
This indicates that the high-pressure annealing process enables the Cu that in-fills the via holes to develop into favorable
microstructures, i.e., single-crystal and with (111) orientation. 相似文献
22.
A simplified probabilistic fault grading method is described. The concept of propagation probability is introduced in place of the sensitization probability of STAFAN, and the empirical parameters of STAFAN are eliminated. The division of input vectors into subsets is monitored by the activation or toggle rate. The accuracy of the method is examined for fault coverage estimation and for predicting the undetected faults. 相似文献
23.
Tsutomu Kanno Hiromasa Tamaki Masato Yoshiya Hiroshi Uchiyama Sachiko Maki Masaki Takata Yuzuru Miyazaki 《Advanced functional materials》2021,31(13):2008469
Mg3Sb2-based intermetallic compounds with exceptionally high thermoelectric performance exhibit unconventional n-type dopability and anomalously low thermal conductivity, attracting much attention to the underlying mechanisms. To date, investigations have been limited to first-principle calculations and thermodynamic analysis of defect formation, and detailed experimental analysis on crystal structure and phonon modes has not been achieved. Here, a synchrotron X-ray diffraction study clarifies that, against a previous view of a simple crystal structure with a small unit cell, Mg3Sb2 is inherently a heavily disordered material with Frenkel defects, charge-neutral defect complexes of cation vacancies and interstitials. Ionic charge neutrality preserved in Mg3Sb2 is responsible for exotic n-type dopability, which is unachievable for other Zintl phase materials. The thermal conductivity of Mg3Sb2 exhibits deviation from the standard T−1 temperature dependency with strongly limited phonon transport due to a strain field. Inelastic X-ray scattering measurement reveals enhanced phonon scattering induced by disorder. The results will draw renewed attention to crystal defects and disorder as means to explore new high-performance thermoelectric materials. 相似文献
24.
A transmission electron microscope (TEM) sample for observing photocatalysis in a liquid was prepared by using N,N,N-trimetyl-N-propylammonium-bis(trifluoromethanesulfonyl)imide. The ionic liquid (IL) was used as a reaction solvent. Tetrachloroauric acid was dissolved in the IL as gold ion species. Rutile particles were added in the solution as a photocatalyst. The low vapor pressure of the IL enables a diffusing system in high vacuum of TEM. Rutile particles were UV irradiated in that liquid phase. After 3 h UV irradiation, a gold particle of 8 nm diameter was grown on the TiO2 surface. Photonucleation of Au/TiO2 system was discussed from the high-resolution TEM images. 相似文献
25.
Tetsuya Iizuka Hideki Sezutsu Ken‐ichiro Tatematsu Isao Kobayashi Naoyuki Yonemura Keiro Uchino Kenichi Nakajima Katsura Kojima Chiyuki Takabayashi Hiroaki Machii Katsushige Yamada Hiroyuki Kurihara Tetsuo Asakura Yasumoto Nakazawa Atsushi Miyawaki Satoshi Karasawa Hatsumi Kobayashi Junji Yamaguchi Nobuo Kuwabara Takashi Nakamura Kei Yoshii Toshiki Tamura 《Advanced functional materials》2013,23(42):5232-5239
Silk is a protein fiber used to weave fabrics and as a biomaterial in medical applications. Recently, genetically modified silks have been produced from transgenic silkworms. In the present study, transgenic silkworms for the mass production of three colors of fluorescent silks, (green, red, and orange) are generated using a vector originating from the fibroin H chain gene and a classical breeding method. The suitability of the recombinant silks for making fabrics is investigated by harvesting large amounts of the cocoons, obtained from rearing over 20 thousand silkworms. The application of low temperature and a weakly alkaline solution for cooking and reeling enables the production of silk fiber without loss of color. The maximum strain tolerated and Young's modulus of the fluorescent silks are similar to those of ordinary silk, although the maximum stress value of the recombinant silk is slightly lower than that of the control. Fabrics with fluorescent color are demonstrated using the recombinant silk, with the color persisting for over two years. The results indicate that large amounts of genetically modified silk can be made by transgenic silkworms, and the silk is applicable as functional silk fiber for making fabrics and for use in medical applications. 相似文献
26.
Numerical evaluations of grid erosions in ion engines are required to estimate the lifetimes of long-term space missions. In this study, to investigate the characteristics of ions colliding with neutrals and impacting the accel grid surface, including ions that collide with neutrals more than once, three-dimensional particle analyses using a full-PIC (Particle in Cell) code were performed. The distributions of erosion by charge-exchanged ions show periodic patterns. The multiple-collided ion constitutes 7 and 8% of the accel grid current to the inner and downstream surfaces, respectively. The energy of the multiple-collided ion impacting the downstream surface has a broader distribution than that of the charge-exchanged ion. These results suggest the importance of investigating multiple-collided ions in high-accuracy quantitative evaluations of grid erosion. 相似文献
27.
Tsutomu Furuzono Koji Seki Akio Kishida Taka-Aki Ohshige Kazunori Waki Ikuro Maruyama Mitsuru Akashi 《应用聚合物科学杂志》1996,59(7):1059-1065
Disiloxane–aromatic polyamide(aramid) multiblock copolymers(2SiPASs) were synthesized using 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane(BATS) as an analog of aramidsilicone resin consisting of aromatic polyamide and poly(dimethylsiloxane) (PDMS). 2SiPASs afford a transparent and toughened plastic film. The surface properties of 2SiPAS were investigated by X-ray photoelectron spectroscopy (xps) and static contact angle measurement. The results of surface analysis suggested that BATS content of the 2SiPAS surface increased with increasing BATS content in bulk. The interaction between the platelets and the 2SiPAS surface was found to be very weak when the BATS content reached 26 wt % in bulk. © 1996 John Wiley & Sons, Inc. 相似文献
28.
Jintong Li Kenichi Tachihara Kazukiyo Nagai Tsutomu Nakagawa Shichang Wang 《应用聚合物科学杂志》1996,60(10):1645-1654
Several sulfolanes such as 3-methylsulfolane, sulfolane, and 3-sulfolene were tested as modifiers in poly(trimethylsilyl methyl methacrylate) (PTMSMMA) and poly(trimethylsilyl propyne) (PMSP) to improve the selectivity of CO2. The gas permeabilities for the PTMSMMA-blend membranes containing high 3-methylsulfolane content were determined on a nonvacuum system in which the membranes started to be measured at their steady states at 30°C; those for all the other membranes were determined in a vacuum system in which those membranes were measured after they reached their unsteady states at 30°C. The PTMSMMA-blend membrane containing 40% 3-methylsulfolane was found to give the best separation of CO2 under the conditions in this study compared to all the PTMSMMA-blend membranes and the others prepared in our work; its ideal separation factors for CO2 over N2 were above 40 and its permeability coefficients of CO2 increased to above 250 Barrer. The modifications of PMSP membranes by impregnating with sulfolane and blending with sulfolene were found to be effective in improving the selectivity for CO2 over N2 for the PMSP membrane. The ideal separation factors for CO2 over N2 for the modified PMSP membranes impregnated with 30% sulfolane and blended with 25% 3-sulfolene were improved to above 10 and 13, respectively. © 1996 John Wiley & Sons, Inc. 相似文献
29.
Nylon-6 substrates were coated with SiO2-RSiO3/2 (R = methyl, vinyl, phenyl) thin films by the sol-gel method, and their water permeability was evaluated Tetraethoxysilane (TEOS) and trifunctional alkoxides such as methyltriethoxysilane (MTES), vinyltriethoxysilane (VTES), and phenyltriethoxysilane (PhTES) were used as starting materials. Water permeability coefficients of the nylon-6 substrates coated with these SiO2-RSiO3/2 thin films were increased with an increase in the content of these trialkoxysilanes in the films. The water permeability coefficients of these coated nylon-6 substrates were smaller in the order of the systems TEOS-PhTES < TEOS-VTES < TEOS-MTES in the relatively low content of the trialkoxysilanes. © 1996 John Wiley & Sons, Inc. 相似文献
30.
Sachiko Kaidzu Tsutomu Okuno Masaki Tanito Akihiro Ohira 《International journal of molecular sciences》2022,23(1)
The effects of visible light, from short to long wavelengths, on the retina were investigated functionally and histologically. The left eyes of Sprague–Dawley albino rats (6-weeks old, n = 6 for each wavelength) were exposed to seven narrow-band wavelengths (central wavelengths, 421, 441, 459, 501, 541, 581, and 615 nm) with bandwidths of 16 to 29 nm (half bandwidth, ±8–14.5 nm) using a xenon lamp source with bandpass filters at the retinal radiant exposures of 340 and 680 J/cm2. The right unexposed eyes served as controls. Seven days after exposure, flash electroretinograms (ERGs) were recorded, and the outer nuclear layer (ONL) thickness was measured. Compared to the unexposed eyes, significant reductions in the a- and b-wave ERG amplitudes were seen in eyes exposed to 460-nm or shorter wavelengths of light. The ONL thickness near the optic nerve head also tended to decrease with exposure to shorter wavelengths. The decreased ERG amplitudes and ONL thicknesses were most prominent in eyes exposed to 420-nm light at both radiant exposures. When the wavelengths were the same, the higher the amount of radiant exposure and the stronger the damage. Compared to the unexposed eyes, the a- and b-waves did not decrease significantly in eyes exposed to 500-nm or longer wavelength light. The results indicate that the retinal damage induced by visible light observed in albino rats depends on the wavelength and energy level of the exposed light. 相似文献