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排序方式: 共有498条查询结果,搜索用时 828 毫秒
491.
N. S. Shahabuddin H. Mohamad M. A. Mahdi Z. Yusoff H. Ahmad S. W. Harun 《Laser Physics》2012,22(1):212-215
A simple multi-wavelength source is demonstrated based on spectral slicing of supercontinuum (SC) light using a Sagnac loop
mirror. A mode locked fiber laser with pulse width of 800 fs is employed to generate the SC in photonic crystal fiber (PCF).
The SC light extending from 1200 nm up to the wavelength region above 1750 nm is obtained at the amplified pulse pump power
of 30 dBm. By slicing the SC with a loop mirror, a multiwavelength comb spectrum is obtained with different channel spacing
for different operating wavelength region. Spacings of 1.5, 2.3, and 2.9 nm are shown at wavelength regions of 1220, 1450,
and 1730 nm, respectively. It is also observed that the signal to noise ratio (SNR) increases from 15 to 20 dB as the operating
wavelength increases from 1220 to 1730 nm region. 相似文献
492.
Stable double spacing multiwavelength Brillouin-Erbium doped fiber laser based on highly nonlinear fiber 总被引:1,自引:0,他引:1
A double frequency spaced multiwavelength Brillouin-Erbium doped fiber laser (BEDFL) with figure-of-eight cavity have been
successfully developed and tested. Double frequency spacing is achieved by using a piece of 2 km of highly nonlinear fiber
(HNLF) as a gain medium. Figure-of-eight configuration removes the odd order Stokes signals via a four-port circulator. Fifteen
Stokes channels are simultaneously generated with a spacing of 0.154 nm that is around 20 GHz, when the Brillouin pump and
980 nm pump powers are fixed at the optimized values of 6 dBm and 40 mW, respectively. Fourteen anti stoke channels are also
obtained, which are generated through four wave mixing (FWM) process in the laser cavity. The output is smooth triangular
comb. The BEFL can also be tuned from 1526.5 to 1567.5 nm. 相似文献
493.
Dual-cavity dual-output multi-wavelength fiber laser based on nonlinear polarization rotation effect
We demonstrate a multi-wavelength fiber laser based on nonlinear polarization rotation (NPR) in dual-cavity configuration with two output ports. The laser employs a piece of erbium doped fiber (EDF) and semiconductor optical amplifier (SOA) as the gain medium in a separate cavity. By incorporating PCF in the dual cavity the non-linear polarization rotation (NPR) effect is enhanced and thus higher output and more oscillating lasing can be achieved. The laser produces three strong lines with a spacing of 2.40 nm and side mode suppression ratio (SMSR) of more than 10 dB at 1535 nm region. Another output produces 8 lines of optical comb with a spacing of 0.54 at 1570 nm region. 相似文献
494.
Suresha N. Deveshegowda Prashant K. Metri Rashmi Shivakumar Ji-Rui Yang Shobith Rangappa Ananda Swamynayaka Muthu K. Shanmugam Omantheswara Nagaraja Mahendra Madegowda Priya Babu Shubha Arunachalam Chinnathambi Sulaiman Ali Alharbi Vijay Pandey Kwang Seok Ahn Peter E. Lobie Basappa Basappa 《Molecules (Basel, Switzerland)》2022,27(9)
A number of uracil amides cleave poly (ADP-ribose) polymerase and therefore novel thiouracil amide compounds were synthesized and screened for the loss of cell viability in a human-estrogen-receptor-positive breast cancer cell line. The synthesized compounds exhibited moderate to significant efficacy against human breast cancer cells, where the compound 5e IC50 value was found to be 18 μM. Thouracil amide compounds 5a and 5e inhibited the catalytical activity of PARP1, enhanced cleavage of PARP1, enhanced phosphorylation of H2AX, and increased CASPASE 3/7 activity. Finally, in silico analysis demonstrated that compound 5e interacted with PARP1. Hence, specific thiouracil amides may serve as new drug-seeds for the development of PARP inhibitors for use in oncology. 相似文献
495.
Algriree Waleed Sulaiman Nasri Isa Maryam M. Sahbudin Ratna K. Z. Hassan Siti L. M. Salman Emad Hmood 《International Journal of Wireless Information Networks》2023,30(1):42-57
International Journal of Wireless Information Networks - The 5G wireless communication system is promised to exploit many kinds of waveform for satisfying various requirements to transmit huge size... 相似文献
496.
Ismael Hajar F. Sulaiman Tukur Abdulkadir Nabi Harivan R. Mahmoud W. Osman M. S. 《Nonlinear dynamics》2023,111(10):9457-9466
Lump solutions are a prominent option for numerous models of nonlinear evolution. The intention of this research is to explore the variable coefficients Kadomtsev–Petviashvili equation. We auspiciously provide multiple soliton and M-lump solutions to this equation. Additionally, the presented results are also supplied with collision phenomena. Owing of its essential role, we employ appropriate parameter values to emphasis the physical characteristics of the provided results using 3D and contour charts. The outcomes of this work convey the physical characteristics of lump and lump interactions that occur in many dynamical regimes.
相似文献497.
498.