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1.
Tetsuo Irifune Chiaki Ueda Shohei Ohshita Hiroaki Ohfuji Takehiro Kunimoto Toru Shinmei 《高压研究》2020,40(1):96-106
ABSTRACTNano-polycrystalline diamond (NPD) with various grain sizes has been synthesized from glassy carbon at pressures 15–25?GPa and temperatures 1700–2300°C using multianvil apparatus. The minimum temperature for the synthesis of pure NPD, below which a small amount of compressed graphite was formed, significantly increased with pressure from ~1700°C at 15?GPa to ~1900°C at 25?GPa. The NPD having grain sizes less than ~50?nm was synthesized at temperatures below ~2000°C at 15?GPa and ~2300°C at 25?GPa, above which significant grain growth was observed. The grain size of NPD decreases with increasing pressure and decreasing temperature, and the pure NPD with grain sizes less than 10?nm is obtained in a limited temperature range around 1800–2000°C, depending on pressure. The pure NPD from glassy carbon is highly transparent and exhibits a granular nano-texture, whose grain size is tunable by selecting adequate pressure and temperature conditions. 相似文献
2.
Yukio Iida Masahiro Shibutani Katsuhiko Kobayashi Kazuhiko Ohnuma Yoichi Miyake Toru Noda 《Optical Review》2006,13(2):87-92
The double-pass method is thought to obtain the point spread function (PSF) in human eyes based on two techniques: the symmetric
double-pass method using the same pupil size and the asymmetric double-pass method using a different pupil size. The symmetric
double-pass method provides autocorrelation of the retinal PSF and, thus, the modulation transfer function. The asymmetric
double-pass method provides low-frequency partial-phase information and the partial phase-retrieval algorithm is applied to
obtain the complete-phase information, and to estimate the PSF. The partial phase-retrieval algorithm is based on the iteration
method proposed by Fineup and Kowalczyk and requires a lengthy computation. In this study, we propose a new high-speed phase-retrieval
algorithm based on the property that the real and imaginary parts of optical transfer functions (OTFs) continuously change
in value. 相似文献
3.
Plasma polymerization of chloromethyltrimethylsilane (CMTMS) was investigated by elemental analysis, infrared spectroscopy, and ESCA, and the modification of Cl substituents in the plasma polymers from CMTMS with sodium azide was discussed. CMTMS was plasma polymerized to yield filmy polymers. The polymer deposition rate was faster than that from tetramethylsilane containing no Cl atom. The plasma polymers from CMTMS were mainly composed of CH3, CH2, Si? CH3, Si? O? Si, and Si? O? C groups with a small amount of C? Cl groups. The Cl substituents incorporated into the plasma polymers were capable of substitution reactions with azide groups to form azide polymers. 相似文献
4.
The existence of a Nash equilibrium in the undiscounted repeated two-person game of incomplete information on one side is
established. The proof depends on a new topological result resembling in some respect the Borsuk-Ulam theorem. 相似文献
5.
Shigeru Tasaka Norihiro Inagaki Masaaki Igawa 《Journal of Polymer Science.Polymer Physics》1991,29(6):691-694
The permeability of annealed poly (l-(trimethylsilyl)-l-propyne) was studied from the viewpoint of structural information obtained from x-ray diffraction and density. The sample cast from benzene solution had low density (0.82 g/cm3) and high permeability, whereas the annealed sample had a higher density (0.88 g/cm3) and permeability lower by two orders of magnitude. The smaller-angle x-ray diffraction peak for each sample, which was likely to reflect the distance between intermolecular chains, increased in intensity and shifted toward higher angle, corresponding to the change of the density with annealing. The logarithmic oxygen permeability was proportional to the density, namely the free volume fraction correlated with the diffusion coefficient and controlled by annealing and swelling by alcohols. 相似文献
6.
Takaaki Kakitsuka Shinji Matsuo Seok–Hwan Jeong Toru Segawa Hiroshi Okamoto Yoshihiro Kawaguchi Yasuhiro Kondo Yuzo Yoshikuni Hiroyuki Suzuki 《Optical and Quantum Electronics》2006,38(12-14):1053-1060
We theoretically investigated a digitally tunable laser with a chirped ladder filter and a ring resonator to obtain a wide wavelength tuning range covering the whole C- or L- band. The clear relation between the tuning range and laser structure, especially the ladder filter, is described analytically. The introduction of a chirped structure into a ladder filter is effective in achieving both wide tunability and a stable lasing mode. A numerical simulation based on multimode rate equations shows that a tuning range of over 40 nm and a mode suppression ratio over 40 dB can be achieved by introducing a chirped ladder filter. 相似文献
7.
A spinel-type structure was found in cadmium stannate CdSnO3 prepared by thermal decomposition of the hydroxostannate CdSn(OH)6 at 550–800°C. Its occurrence depends strongly on the precipitation conditions of CdSn(OH)6 from CdCl2 and Na2Sn(OH)6 aqueous solutions. In the (Cd1–xCax)SnO3 system, the spinel phase appears in the composition range of 0.0 ≤ x ≤ 0.35. The experimental results suggest the presence of cation vacancies in the spinel octahedral sites. 相似文献
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10.
Takuya Hasegawa Hirotaka Matsuura Kazumi Inagaki Hiroki Haraguchi 《Analytical sciences》2003,19(1):147-150
The major-to-ultratrace elements in human bone-marrow fluid were determined by ICP-AES (inductively coupled plasma atomic emission spectrometry), and ICP-MS (inductively coupled plasma mass spectrometry). The bone-marrow fluid sample was centrifuged prior to acid digestion to exclude the bone piece from bone marrow, and then digested with nitric acid. As a result, 20 elements could be determined over the concentration range from 1610 microg g(-1) for Na to 0.00043 microg g(-1) for W. It was found that Fe, Zn and Sb were enriched by ca. 264-, 7- and 15-fold, respectively, in bone-marrow fluid, compared to those in human blood serum. Alkali metals (K, Rb, Cs), except for Na, were also significantly enriched in bone-marrow fluid. Furthermore, the concentrations of various elements, such as Fe, P, Al, Zn, Cu, Se, Zr, Sn, Ag and W, were significantly higher than those in open seawater. 相似文献