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161.
Sudo Shoichi Okazaki Hisaaki Nakahara Motohiro Horiguchi Masaharu 《Electronics letters》1980,16(8):280-281
A 30.4 km graded-index fibre has been fabricated by the vapour-phase axial deposition (v.a.d.) method. Optical-time-domain reflectometry was used to characterise the loss uniformity along the longitudinal direction of this fibre. Measured transmission loss and 6 dB bandwidth with good uniformity along this long fibre were 0.54 dB/km and 1200 MHzkm at the 1.3 ?m wavelength, respectively. 相似文献
162.
163.
Masaharu Yamaguchi Yukichi Umakoshi Takuji Kondo Genjiro Mima 《Metallurgical and Materials Transactions B》1971,2(5):1293-1296
Copper wire containing strong chromium ferrite needles has been produced by aligning the chromium ferrite phase of a two-phase Cu?Fe?Cr alloy into needles by cold drawing and subsequently annealing the wire at 480°C. At this temperature the chromium ferrite needles exhibit marked age-hardening. The volume fraction of the chromium ferrite needles in the alloy investigated was nearly 25 pct. Strength up to 50 kg per sq mm with nearly 8 pct elongation has been achieved in 3 mm-wire annealed at 480°C. The annealed wire can be drawn again to give a further increase in strength up to 73 kg per sq mm. 相似文献
164.
This paper describes an implementation of a system for fuzzy sets manipulation which is based on fstds (Fuzzy-Set-Theoretic Data Structure), an extended version of Childs's stds (Set-Theoretic Data Structure). The fstds language is considered as a fuzzy-set-theoretically oriented language which can deal, for example, with ordinary sets, ordinary relations, fuzzy sets, fuzzy relations, L-fuzzy sets, level-m fuzzy sets and type-n fuzzy sets. The system consists of an interpreter, a collection of fuzzy-set operations and the data structure, fstds, for representing fuzzy sets. fstds is made up of eight areas, namely, the fuzzy-set area, fuzzy-set representation area, grade area, grade-tuple area, element area, element-tuple area, fuzzy-set name area and fuzzy-set operator name area. The fstds system, in which 52 fuzzy-set operations are available, is implemented in fortran, and is currently running on a FACOM 230-45S computer. 相似文献
165.
The electric birefringence of poly(ε-carbobenzoxy-l-lysine) (PCBL) in various helicogenic organic solvents and solvent mixtures has been measured over a wide range of field strengths by application of rectangular pulses. The apparent permanent dipole moment and the optical anisotropy factor were separately determined from the field strength dependence of the steady-state birefringence. The apparent dipole moment per residue for a PCBL sample with molecular weight close to 1 × 105 fell in the range of 4.7 to 5.9 D in spite of the large variation of the solvent dielectric constant. The optical anisotropy factor was appreciably small and changed its sign depending upon the solvent. The intrinsic birefringence of PCBL was found to be negative in sign on the basis of the Peterlin-Stuart theory. This was interpreted in terms of the orientation of the side chains with respect to the helical backbone. The apparent dipole moment per residue for high molecular weight PCBL samples was much smaller, indicating a considerable flexibility of the helix. 相似文献
166.
Uwe Schneider Masaharu Sugiura Sh Kobayashi 《Advanced Synthesis \u0026amp; Catalysis》2006,348(3):323-329
167.
The Rayleigh scattering of the mixed-alkali glass system K2 O–Na2 O–MgO–SiO2 (KNMS) was investigated, both experimentally and theoretically. The lowest Rayleigh scattering coefficient (38% of that for pure SiO2 glass) was obtained when the glass composition was 22K2 O–8Na2 O–10MgO–60SiO2 (in mol%). These values are equal to or less than the minimum values reported for the ternary sodium silicate glass Na2 O–MgO–SiO2 . The Rayleigh scattering caused by concentration fluctuation was believed to have been reduced greatly in this KNMS glass, because the mobility of the alkali-metal ions was reduced by the mixed-alkali effect. 相似文献
168.
Hideyuki Konishi Chikako Ogawa Masaharu Sugiura Sh Kobayashi 《Advanced Synthesis \u0026amp; Catalysis》2005,347(15):1899-1903
Cyanation of N‐acylhydrazones using trimethylsilyl cyanide (TMSCN) proceeded well in the presence of an amine to afford the corresponding α‐hydrazinonitriles in high yields. For less reactive substrates, the combined use of an amine and a catalytic amount of scandium triflate [Sc(OTf)3] was effective to promote the reactions. The mechanistic study suggested that the amine worked as a Brønsted base. 相似文献
169.
170.
The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves
vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni/sapphire substrates. The improved crystallinity
of the metal film, assisted by the sapphire substrate, proves to be the key to the quality of as-grown graphene film. The
crystallinity of the Co and Ni metal films was improved by sputtering the metal at elevated temperature as was verified by
X-ray diffraction (XRD). After sputtering of a-C and annealing, large area, single layer graphene that occupies almost the
entire area of the substrate was produced. With this method, 100 mm2-area single layer graphene can be synthesized and is limited only by the substrate and vacuum chamber size. The homogeneity
of the graphene film is not dependent on the cooling rate, in contrast to syntheses using polycrystalline metal films and
conventional chemical vapor deposition (CVD) growth. Our facile method of producing single layer graphene on Co and Ni metal
films should lead to large scale graphene-based applications. 相似文献