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排序方式: 共有1005条查询结果,搜索用时 46 毫秒
41.
Hideo Yamashita Tatsuya Johkoh Shinichi Takita Eihachiro Nakamae 《Computer Animation and Virtual Worlds》1991,2(1):34-40
In order to observe the physical values (magnetic flux density and eddy current) in 3D magnetic field analysis, an interactive and highly manipulative visualization system depicting stereo images is intalled in a graphics workstation with high functional graphic processors. The system has the following characteristics:
- 1 An interactive and highly manipulative menu window with many functions: it enables visualization of complex phenomena in a 3D field through observation of various combinations of physical values from various viewpoints.
- 2 Simultaneous display of both magnetic flux density and eddy current by using the appropriate use of two colour display methods for stream lines and distribution maps of density: this function facilitates observation of the mutual relations between two physical values in a 3D field.
- 3 Animations and stereo displays: since they give extremely distinct images, observers can easily understand even highly complex 3D phenomena.
42.
Co-Ni-Al合金不仅可以作为铁磁性形状记忆合金,也是传统和高温形状记忆合金的候选材料,本文通过金相显微分析,DSC和VSM方法,研究了Co40Ni33.5Al26.5合金马氏体相变和Curie点随淬火温度变化的情况,结果发现该合金马氏体相变温度和Curie点与淬火温度成正比关系.马氏体相变的4种温度,即Ms、Mf、As和At基本平行变化,淬火温度每升高10℃,马氏体相变温度升高8~9℃,而Curie点升高6~7℃.其马氏体相变温度和Curie点随淬火温度的变化与基体相β的成分变化有关,β相中Al的含量随淬火温度升高而降低,因而马氏体相变温度和Curie点升高.并且发现随着淬火温度升高,Co40Ni33.5Al26.5合金马氏体相的磁晶各向异性有减弱的倾向. 相似文献
43.
Eisner Salamanca Yu-Hwa Pan Ying-Sui Sun Hao-Wen Hsueh Odontuya Dorj Wan-Ling Yao Jerry Chin-Yi Lin Nai-Chia Teng Ikki Watanabe Shinichi Abe Yi-Fan Wu Wei-Jen Chang 《International journal of molecular sciences》2022,23(3)
In vitro, in vivo, and clinical studies have shown how the physicochemical and biological properties of β-tricalcium phosphate (β-TCP) work in bone regeneration. This study aimed to improve the properties of β-TCP by achieving optimum surface and bulk β-TCP chemical/physical properties through the hydrothermal addition of magnesium (Mg) and to later establish the biocompatibility of β-TCP/Mg for bone grafting and tissue engineering treatments. Multiple in vitro and in vivo analyses were used to complete β-TCP/Mg physicochemical and biological characterization. The addition of MgO brought about a modest rise in the number of β-TCP surface particles, indicating improvements in alkaline phosphatase (ALP) activity on day 21 (p < 0.05) and in the WST-1assay on all days (p < 0.05), with a corresponding increase in the upregulation of ALP and bone sialoprotein. SEM analyses stated that the surfaces of the β-TCP particles were not altered after the addition of Mg. Micro-CT and histomorphometric analysis from rabbit calvaria critical defects resulted in β-TCP/Mg managing to reform more new bone than the control defects and β-TCP control at 2, 6, and 8 weeks (* p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, and **** p ≤ 0.0001). The hydrothermal addition of MgO to the β-TCP surfaces ameliorated its biocompatibility without altering its surface roughness resulting from the elemental composition while enhancing cell viability and proliferation, inducing more bone regeneration by osteoconduction in vivo and osteoblastic differentiation in vitro. 相似文献
44.
Talc-containing polypropylene (PP) resin is extensively employed in automobiles. Herein, considering the microstructure transfer process in injection molding, the effect of the talc's dispersibility and particle size on this process and its impact on the gloss level of the product were investigated. Results show that a fine unevenness of about several micrometers was self-formed by the shrinkage of PP in nontransferred areas due to the blending of talc. Additionally, the amount of self-formed unevenness tended with an increase in the average particle size of talc. Furthermore, due to PP shrinkage and different densities of talc, it was observed that a fine tiger-stripe pattern was self-formed using special molds with modified microstructure. This self-formed fine unevenness changes the gloss level owing to the diffused light reflection effect. This study proposes controlling this change by controlling the average particle size of talc and structure of the mold. POLYM. ENG. SCI., 60:132–139, 2020. © 2019 Society of Plastics Engineers 相似文献
45.
46.
We studied the use of poly(ethylene glycol) (PEG)-modified dendrimers as a nanocapsule with a biocompatible surface. We designed PEG-modified dendrimers having a shell of hydrophobic amino acid residues in the peripheral moiety of the dendrimer to increase their encapsulation ability. Subsequently, l-phenylalanine or γ-benzyl-l-glutamate residues were introduced to all chain ends of the poly(amidoamine) G4 dendrimers. Furthermore, PEG (MW 2000) chains were attached to the amino acid residues. These hydrophobic amino acid residues rendered the PEG-modified dendrimers as more compact. After binding of Rose Bengal (RB) guest molecules to dendrimers, an assay using the Klotz plot showed that the hydrophobic amino acid layer slightly affected the guest site number, but significantly increased intrinsic binding of the dendrimers to guest molecules. The PEG-modified dendrimers with the hydrophobic amino acid layer were better able to retain guest molecules than the dendrimer without the layer: they are therefore useful for drug delivery. 相似文献
47.
Masahiko Nakase Tohru Kobayashi Hideaki Shiwaku Shinichi Suzuki Travis S. Grimes Bruce J. Mincher 《溶剂提取与离子交换》2013,31(7):633-646
ABSTRACTTo effectively separate lanthanides (Ln(III)) from actinides (An(III)), symmetrical 2,2′-bipyridyl (Bpy), 1,10-phenanthroline (Phen), and unsymmetrical N-methyl-N-tolyl-1,10-phenanthroline-2-carboxamide (MeTol-PTA) were investigated. According to the crystal structures and EXAFS experiments, the decreasing ionic radius from light to heavy Ln led to decreases in the Ln–N (Bpy) and Ln–N (Phen) distances, while log β simply increased due to the electrostatic interaction and the order of Ln–O (MeTol-PTA) < Ln–N (Bpy, Phen) < Ln–N (MeTol-PTA) was obtained. This indicated that the bulky phenanthroline moiety of MeTol-PTA may not allow N (MeTol-PTA) to come close to Ln. Consequently, the log β of MeTol-PTA exhibited a local maximum (around Nd). 相似文献
48.
49.
Guanghui Cui Masamichi Fujikawa Shusaku Nagano Masami Sano Hiroshi Takase Tsukasa Miyazaki Shinichi Sakurai Katsuhiro Yamamoto 《Polymer》2014
Polystyrene-b-poly(methyl acrylate) (PS-b-PMA) block copolymer with PS volume fraction of 25.2 vol% was synthesized by atom transfer radical polymerization. Non-pretreated silicon wafers were used as the substrates to prepare perpendicular oriented PS cylinders in PMA matrix via solvent annealing which could induce the transformation of spheres to vertically oriented and hexagonally packed cylinders. The spherical microdomains were formed after the evaporation of solvents from the solutions of the block copolymer in selective solvents mixed from methanol, acetone and dichloromethane. The thickness of films could be as thick as 1000 nm, which were much thicker than usual cases and the cylinders came from the directional coalescence of the spheres, thus any pre-treatments of the substrates were not required for perpendicular orientation. The structures were characterized by small angle X-ray scattering (SAXS), transmission electron microscope (TEM), atom force microscopy (AFM) and grazing incidence small angle X-ray scattering (GISAXS). 相似文献
50.
T. Hirao S. Onoda M. Oikawa T. Satoh T. Kamiya T. Ohshima 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(12-13):2216-2218
Single Event Effects (SEEs) triggered by energetic heavy ions traversing a sensitive parts of electric devices have been studied using high-energy heavy ion microbeams connected with Transient Ion Beam Induced Current (TIBIC) measuring system at the Japan Atomic Energy Agency (JAEA) Takasaki Ion Accelerators for Advanced Radiation Applications (TIARA) facility. In the TIBIC system, SEE for semiconductor device, that is fast charge collection, has been observed in timescales of the order of picoseconds. In this paper, we show successful demonstration of the performance of the system, in which clear images of TIBIC map have been observed for Si pin photodiodes irradiated by 260 MeV 20Ne7+ and also by 520 MeV 40Ar14+ microbeams. 相似文献