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81.
Hiromasa Yagyu Yoshikazu Hirai Akio Uesugi Yoshihide Makino Koji Sugano Toshiyuki Tsuchiya Osamu Tabata 《Polymer》2012,53(21):4834-4842
The mechanical properties of an epoxy-based chemically amplified resists with various cross-linking ratios were simulated using a newly developed coarse-grained molecular dynamics simulation that employs a bead–spring model. Models with the different cross-linking ratios were created in the molecular dynamics calculation step and uniaxial elongation simulations were performed. The results reveal that the simulated elastic modulus of the resist modeled by the Kremer–Grest model with an extended angle bending potential depends on the cross-linking ratio, its dependency exhibits good agreement with that determined by nanoindentation tests. 相似文献
82.
83.
Tomohiro Kasakawa Hiroki Tabata Ryo Onodera Hiroki Kojima Mutsumi Kimura Hiroyuki Hara Satoshi Inoue 《Solid-state electronics》2011,56(1):207-210
We propose degradation evaluation of poly-Si TFTs by comparing normal and reverse characteristics. Since symmetrical normal and reverse characteristics indicate Joule-heating degradation whereas asymmetrical characteristics indicate hot-carrier degradation, they can be clearly and easily classified. Moreover, degradation occurrence is contrasted between standard and fine TFTs. Finally, behavior of the hot-carrier degradation is analyzed. 相似文献
84.
Although the production of electro‐conductive aramid fibers is efficient, the method needs to be modified before it can be applied to aramid films. Whereas impregnation of an aramid film with a metal complex using supercritical CO2 is achievable, the relatively low adhesion strength of the metal layer applied using electroless copper plating is problematic. To solve this problem, thermal treatment was conducted before, after, or both before and after electroless plating. The rationale for using thermal treatment to improve the adhesiveness of the plated layer was based on the findings that (1) an aramid film contains a significant amount of water (about 3.5 % w.o.f.), which might have a negative impact on adhesion; and (2) because an impregnated metal complex liberates metal catalyst by thermal decomposition during impregnation, a supplementary thermal action might liberate more catalyst and thereby improve adhesion. We found that thermal treatment improved adhesion of the metal layer to the aramid film. Moreover, we discovered that with respect to electroless copper plating, a short time‐lag was crucial to obtaining a thin and homogeneous metal layer with strong adhesion. In addition, we demonstrate the affinity of an aramid film for Pd(acac)2. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
85.
Kuniaki Gotoh Takashi Kawazu Mikio Yoshida Jun Oshitani 《Advanced Powder Technology》2010,21(1):34-40
A method for dispersing dry particles in a liquid is described. The method involves coating large carrier particles with fine particles. When two types of particles having different sizes are mixed in dry conditions, the particles adhere to one another, and the large particles become coated with small particles. When the large core particles are coated with a mono-layer of small particles, further agglomeration is inhibited. Because the single small particles generated by the disruption adhere to the core particles, we presumed that, if the small particles that are adhered to large particles could be separated from the large particles by a sonication in a liquid, the dry fine particles could be dispersed in a liquid.The dispersion experiments conducted using spherical silica particles having a count median diameter Dp50 of 74 nm as small particles and spherical glass beads as large particles. In this situation, the large particles carry the small particles from a dry condition into a liquid. We refer to the large particles as carrier particles. The experiments revealed that the proposed dispersion procedure results in a superior product, compared to sonication only. The effect of carrier size on dispersion performance is also investigated. The findings indicate and an optimum carrier size exists. Observations of the carrier particle surfaces after dry mixing indicate that the optimum condition is the condition at which a mono-layer of Silica particles is formed. 相似文献
86.
Two different murdochite-type mixed oxides, (Mg6–x
Li
x
)MnO8 (x = 0, 0.1, 0.2 and 0.3) and (Mg6–x
Al
x
)MnO8 (x = 0, 0.2, 0.4, 0.6) were examined for the catalytic decomposition of N2O in order to make clear the effects of mixed valencies of pairing manganese ions and oxygen vacancies. The valence of manganese ions and the amount of surface oxygen vacancies have been examined with X-ray photoelectron spectroscopy (XPS). (Mg6–x
Li
x
)MnO8 had mixed valence manganese ions and oxygen vacancies on the surface after the substitution. The substituted (Mg6–x
Al
x
)MnO8 had a mixed valence state but oxygen vacancies decresed with x and excess oxygen over stoichiometry was observed at x = 0.4 and 0.6. The reaction rate of N2O decomposition increased after substitution with lithium but hardly increased after the substitution with aluminum in (Mg6–x
A
x
)MnO8. We assumed that the presence of oxygen vacancies on the surface along with pairing altervalent manganese ions affected strongly to enhance the reactivity of N2O decomposition. 相似文献
87.
A protein based 3D porous scaffold is fabricated by blending gelatin and albumin. The biomimetic biodegradable gelatin, promoted good cell adhesion and its hydrophilic nature enabled absorption of culture media. Albumin is proposed to serve as a nontoxic foaming agent and also helped to attain a hydrophobic-hydrophilic balance. The hydrophobic-hydrophilic balance and appropriate crosslinking of the scaffold avoided extensive swelling, as well as retained the stability of scaffold in culture medium for long period. The scaffold is found to be highly porous with open interconnected pores. The adequate swelling and mechanical property of the scaffold helped to withstand the loads imparted by the cells during in vitro culture. The scaffold served as a nontoxic material to monolayer of fibroblast cells and is found to be cell compatible. The suitability of scaffold for chondrocyte culture and stem cell differentiation to chondrocytes is further explored in this work. The scaffold provided appropriate environment for chondrocyte culture, resulting in deposition of cartilage specific matrix molecules that completely masked the pores of the porous scaffold. The scaffold promoted the proliferation and differentiation of mesenchymal stem cells to chondrocytes in presence of growth factors. The transforming growth factor, TGFbeta3 promoted better chondrogenic differentiation than its isoform TGFbeta1 in this scaffold. 相似文献
88.
Yoshiki Hoshide Yusuke Komura Akimori Tabata Akihiko Kitagawa Akihiro Kondo 《Thin solid films》2009,517(12):3520-3523
Silicon carbide (SiC) thin films were prepared by hot-wire chemical vapor deposition from SiH4/CH4/H2 and the influence of H2 gas flow rate (F(H2)) on the film properties was investigated. The SiH4 gas flow rate was 1 sccm. At the CH4 gas flow rate (F(CH4)) of 1 sccm, nanocrystalline cubic SiC (nc-3C-SiC) grew even without H2. On the other hand, at F(CH4) = 2 sccm, amorphous SiC grew without H2 and nc-3C-SiC grew above F(H2) = 50 sccm. As F(H2) was increased, the crystallinity improved both at F(CH4) = 1 and 2 sccm. However, the mean crystallite size decreased at F(CH4) = 1 sccm and increased at F(CH4) = 2 sccm. We discuss growth mechanisms of nc-3C-SiC. 相似文献
89.
Silicon carbide (SiC) thin films were prepared by hot-wire chemical vapor deposition from SiH4/CH4/H2 and their structural properties were investigated by X-ray diffraction, Fourier transform infrared absorption and Raman scattering spectroscopies. At 2 Torr, Si-crystallite-embedded amorphous SiC (a-Si1 − xCx:H) grew at filament temperatures (Tf) below 1600 °C and nanocrystalline cubic SiC (nc-3C-SiC:H) grew above Tf = 1700 °C. On the other hand, At 4 Torr, a-Si1 − xCx:H grew at Tf = 1400 °C and nc-3C-SiC grew above Tf = 1600 °C. When the intakes of Si and C atoms into the film per unit time are almost the same and H radicals with a high density are generated, which takes place at high Tf, nc-3C-SiC grows. On the other hand, at low Tf the intake of Si atoms is larger than that of C atoms and, consequently, Si-rich a-Si1 − xCx:H or Si-crystallite-embedded a-Si1 − xCx:H grow. 相似文献
90.