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1.
Kanai M Porfyrakis K Briggs GA Dennis TJ 《Chemical communications (Cambridge, England)》2004,(2):210-211
We report the purification of the nitrogen-containing incar-fullerenes iNC(60) and iNC(70), and their characterisation by UV-Vis absorption spectroscopy. 相似文献
2.
3.
Low-threshold and high temperature single-longitudinal-mode operation of 1.55 ?m-band DFB-DC-PBH LDs
1.55 ?m-band distributed-feedback laser diodes with double-channel planar buried heterostructure (DFB-DC-PBH LDs) have been developed. As well as low threshold current, 19 mA at room temperature, stable CW single-longitudinal-mode operation up to the high power level of 23 mW and the high temperature of 108°C has been obtained. 相似文献
4.
High-power aging tests on 1.3 ?m double-channel planar buried-heterostructure (DC-PBH) lasers with a reflective coated mirror have been performed. Stable operation for over 6000 h has been demonstrated under constant power conditions of 20 and 30 mW from the front facet at 50°C. 相似文献
5.
Yoshida Y Tateiwa N Mito M Kawae T Takeda K Hosokoshi Y Inoue K 《Physical review letters》2005,94(3):037203
We have measured the specific heat of an S = 1/2 antiferromagnetic alternating Heisenberg chain pentafulorophenyl nitronyl nitroxide in magnetic fields up to H > H(C2). This compound has a field-induced magnetic ordered (FIMO) phase between H(C1) and H(C2). Characteristic behaviors are observed depending on the magnetic field up to above H(C2) outside of the H-T boundary for the FIMO. The temperature and field dependence of the specific heat are qualitatively in good agreement with the theoretical calculation on an S = 1/2 two-leg ladder [Wang et al., Phys. Rev. Lett. 84, 5399 (2000)]]. This agreement suggests that the observed behaviors are related with the low-energy excitation in the Tomonaga-Luttinger liquid. 相似文献
6.
Yamazaki S. Emura K. Shikada M. Yamaguchi M. Mito I. Minemura K. 《Electronics letters》1986,22(1):5-7
High receiver sensitivity (?51.9 dBm) and long span (243 km) transmission expriments have been achieved with a 140 Mbit/s optical FSK heterodyne single-filter detection system, using a phase-tunable DFB laser diode as a transmitter. This has enabled direct FSK modulation without waveform distortion. Also, a 280 Mbit/s 204 km transmission experiment has been carried out successfully. 相似文献
7.
Issues related to realizing high light output-power single-longitudinal-mode InGaAsP/InP DFB LD's have been studied experimentally and theoretically. Asymmetry in the reflections as the front and rear facets of DFB cavity has been found to result in enhanced single-longitudinal-mode selectivity and higher light output power from the front facet. Single-longitudinal-mode CW light output power as high as 103 mW has been obtained in a 1.3-μm DFB-DC-PBH LD with facet reflectivities of 2 and 80-90 percent. Low internal quantum efficiency is pointed out to be an important problem for 1.5-μm LD's. 相似文献
8.
1.5 mu m band travelling-wave semiconductor optical amplifiers (TWAs), characterised by their window facet structure and symmetrised active waveguide, have been developed. 1.5 dB spectral gain ripple and 1.3 dB TE-TM mode gain difference at 22 dB signal gain were achieved simultaneously. An average facet reflectivity as low as 0.06% was estimated.<> 相似文献
9.
Kitamura M. Yamazaki H. Sasaki T. Kida N. Hasumi H. Mito I. 《Photonics Technology Letters, IEEE》1990,2(5):310-311
The spectral linewidth observed in a 1.5 μm multiple-quantum-well distributed-feedback laser diode (MQW-DFB-LD) with 1500 μm cavity length is discussed. The spectral linewidth was drastically reduced in long-cavity MQW-DFB0-LDs through a reduction in threshold carrier density. A spectral linewidth of 250 kHz, the narrowest ever achieved, was obtained 相似文献
10.
Nitroxyl radicals (nitroxides) with unpaired electron are widely used as antioxidants, contrast agents, and spin probes. Although piperidine nitroxyl radicals have many applications, these are mainly tetramethylpiperidine compounds, and only a few reports consider the substitution of N-O surround as a reaction site, such as 2,2,6,6-tetrasubstituted piperidine nitroxyl radicals. Our results revealed that the 2,6-position of the 2,2,6,6-tetramethylpiperidin-4-one compound was substituted by cyclohexyl groups to produce 2,2,6,6-tetrasubstituted piperidin-4-one derivatives under mild reaction conditions. An interesting result was obtained by using 15N-labeled NH4Cl instead of 14NH4Cl: it gave 15N-labeled 2,2,6,6-tetrasubstituted piperidin-4-one-1-oxyls with a high 15N content. In conclusion, the new method for the synthesis of nitroxyl radicals readily yields 2,2,6,6-tetrasubstituted piperidin-4-one under mild conditions. 相似文献