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61.
A highly efficient gain-clamped L-band EDFA with improved noise figure characteristic is demonstrated by simply adding a broadband
C-band FBG in double-pass system. The combination of the FBG and optical circulator has created laser in the cavity for gain
clamping. By adjusting the power combination of pumps 1 and 2, the clamped gain level can be controlled. The amplifier gain
is clamped at 28.1 dB from −40 to −25 dBm with a gain variation of less than 0.5 dB by setting the pumps 1 and 2 at 59.5 and
50.6 mW, respectively. The gain is also flat from 1574 nm to 1604 nm with a gain variation of less than 3 dB. The corresponding
noise figure varies from 5.6 to 7.6 dB, which is 0.8 to 2.6 dB less than those of unclamped amplifier. 相似文献
62.
A. S. Sulaiman M. Y. A. Rahman A. A. Umar M. M. Salleh 《Russian Journal of Electrochemistry》2018,54(1):56-61
This paper is concerned with a study of the influence of synthesis temperature on the properties of TiO2 films and the performance of dye-sensitized solar cell (DSSC). The TiO2 film samples synthesized via liquid phase deposition for 5 h at various temperatures, namely, 40, 50, 60, 70 and 80°C. It was found that the morphological shape of the film changes with growth temperature. The optical absorption increases with growth temperature. However, the photoluminescence decreases with growth temperature. These TiO2 samples were applied in a DSSC of ITO/TiO2/electrolyte/platinum. The DSSC utilizing the sample grown at 40°C demonstrated the highest photovoltaic parameters with the Jsc, and η of 1.40 mA cm–2 and 0.44% respectively. This is due to the smallest grain size of TiO2 films and the smallest bulk resistance of the device. 相似文献
63.
The differential pulse polarographic behaviour of benzoylhydrazine, m-methoxy benzoyl-hydrazine, and o-methoxy benzoylhydrazine has been investigated in Britton-Robinson buffer. The peaks obtained at pH 5 are recommended for the microdetermination of these compounds. The benzoylhydrazine can be obtained with high degrees of accuracy with an experimental detection limit of 4 × 10−6 M in simple aqueous and aqueous ethanol mixtures. 相似文献
64.
Shukri B. Sulaiman N. Sahoo Sudha Srinivas F. Hagelberg T. P. Das E. Torikai K. Nagamine 《Hyperfine Interactions》1993,79(1-4):901-907
The location of the positive muon used as a probe in highT
c systems is investigated using the unrestricted Hartree-Fock cluster procedure. Our calculations indicate that + is located in thea–c plane at a distance of 1.08 Å from the apical oxygen at a +-O(a)-Cu angle of 25°. The hyperfine field at this site is also calculated. Our results show the importance of including the local contact and dipolar contributions to the hyperfine field which arise from the unpaired electron spin distribution in the vicinity of the muon. 相似文献
65.
The differential pulse polarographic behavior of p-nitrosodimethylaniline has been investigated in Britton-Robinson buffer and phosphate buffer. The peak obtained at pH 8.0 is recommended for the trace determination of this compound, with an experimental detection limit of 18 ppb (1.2 × 10?7M) in simple aqueous solution. The method is also applied for the indirect microdetermination of NADH. The experimental detection limit of NADH is shown to be 1.05 × 10?6M. 相似文献
66.
P. MORLIÉRE M. BAZIN L. DUBERTRET R. SANTUS T. SA E. MELO G. HÜPPE J. HAIGLE P. FORLOT A. BERNARD 《Photochemistry and photobiology》1991,53(1):13-19
5-Geranoxypsoralen, commonly called bergamottin, a major furocoumarin contained in bergamot oil, is reported in vitro as a highly photoreactive psoralen. In ethanol, it exhibits quite a high triplet state quantum yield (approximately 0.37). The triplet state is involved in subsequent photochemistry which depends on the initial concentration and on the presence of oxygen. In contrast to most psoralens, absorption and fluorescence data suggest that 5-geranoxypsoralen does not interact with DNA in the dark. No UVA-induced interstrand cross-links in DNA were shown. 相似文献
67.
W.T. Sulaiman 《Applied mathematics and computation》2010,216(9):2645-2648
In this note we give an improvement to a recent result obtained by Savas and Rhoade concerning ∣A∣k summability of infinite series. 相似文献
68.
69.
P. S. Pereira Silva Raza Murad Ghalib Sayed Hasan Mehdi Rokiah Hashim Othman Sulaiman Ali Jawad 《Journal of chemical crystallography》2010,40(12):1150-1154
Abstract
Cyclohexyl N-phenylcarbamate, C13H17NO2 (I), which is a useful target for biotransformations by fungi, has been synthesized and the structure has been solved by X-ray diffraction. The crystals are triclinic, space group P [`1] \bar{1} , with a = 5.2581 (2) ?, b = 9.5080 (3) ?, c = 12.6165 (4) ?, α = 70.544 (2)°, β = 89.075 (2)°, γ = 80.447 (2)°, M r = 219.28, V = 585.96 (3) ?3, Z = 2 and R = 0.065. In the title compound the phenyl ring makes a dihedral angle of 30.68(7)° with the carbamate group The molecules are linked into infinite chains via N–H···O hydrogen bonds along the a axis. These hydrogen-bonded chains are further linked by weaker C–H···π interactions. Quantum-mechanical ab initio calculations for the free molecule reproduce well the observed bond lengths and valency angles but show that the crystal packing might be responsible for the rotation of the phenyl ring out of the carbamate plane in the solid state conformation. 相似文献70.
Kh.S.Karimov Khaulah Sulaiman Zubair Ahmad Khakim M.Akhmedov A.Mateen 《中国物理 B》2015,24(1):18801-018801
We report newly designed pressure and displacement capacitive sensors based on a flexible paper–CNT structure.The carbon nanotube(CNT)powder was deposited on a thin paper substrate and was pressed at an elevated temperature.The sheet resistance of the paper–CNT films was in the range of 2–4 kΩ/cm2.The paper–CNT films were used to fabricate pressure and displacement sensors.The sensitivities of the pressure and the displacement sensors were found to be17.3 p F·m2/k N and 0.93 10-3p F/μm,respectively.The experimental results were compared with the simulated data and they found good agreement with each other. 相似文献