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981.
K.Khairi H.Fong Kok Z.Lambak M.I.Abdan M.A.Farhan M.H.Othman M.L.H.Jamaluddin S.A.Mohamad Rofie Tee Din Chai K.Chia Ching A.Mohd.Ramli M.A.Mokhtar S.A.Syed Ahmad M.Mokhtar S.B.Ahmad Anas M.A.Mahdi 《中国光学快报(英文版)》2018,(4)
We experimentally designed dispersion-managed repeaterless transmission systems with a pre-compensation and post-compensation technique using multi-channel-chirped fiber Bragg gratings. The repeaterless transmission link supports a single channel(1548.51 nm) with a 10 Gbps repeaterless transmission system over 300 km standard single-mode fiber(SSMF). In the system design, two distributed Raman amplifiers(DRAs) were used to improve the signal level propagated along the 300 km SSMF. The co-propagating DRA provided 15 dB on–off gain and the counter-propagating produced 32 dB on–off gain at the signal wavelength. The experiment results show that the post-compensation configuration achieves an optimal performance with a bit error rate at 1 × 10~(-9). 相似文献
982.
Nikolai Lebedev Syed Mahmud Igor Griva Anders Blom Leonard M. Tender 《Journal of Polymer Science.Polymer Physics》2015,53(24):1706-1717
Geobacter sulfurreducens pili composed of the Type IV pili structural peptide PilA have been implicated as efficient electronic conductors. Though investigated experimentally, no detailed theoretical studies have been performed to date that provide quantitative estimation of the transmission spectrum, electron transfer (ET) paths, efficiency of current generation, and other factors needed for understanding possible mechanisms of conductivity. In the present work, we calculate from first principles the possibilities of electron tunneling through 3 PilA fragments which structure was identified recently by NMR. The results indicate that positively charged amino acids, arginines and lysines form electrostatic traps in the middle of the peptide preventing ET at low bias voltages (<~6 V). At higher biases the traps are filled with electrons making possible sequential electron tunneling through the central part of the protein. In addition, leucines and phenylalanines form ET loops facilitating electron stabilization within the protein and sequential ET. Our results indicate that ET through the PilA protein cannot occur by coherent ET, but suggest a sequential (incoherent) mechanism. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1706–1717 相似文献
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Roheena Abdullah Wajeeha Zafar Muhammad Nadeem Mehwish Iqtedar Shagufta Naz Quratulain Syed 《Natural product research》2015,29(4):336-344
This study deals with the isolation of novel mutant of Bacillus and optimisation of media for the hyperproduction of cellulase. Cellulase-producing Bacillus PC-BC6 was subjected to physical and chemical mutagenesis to enhance the cellulolytic potential. Later, mutagenesis isolates were screened both qualitatively and quantitatively. Among all the tested isolates, Bacillus N3 yielded maximum (CMCase 1250 IU/mL/min and FPase 629 IU/mL/min) activity. The Bacillus N3 strain exhibited 1.7-fold more enzyme production as compared with the parental strain. Proximate analysis of untreated and pretreated Saccharum spontaneum was carried out to improve cellulase production. Three different media were tested for the production of cellulase, among which M2 medium containing MgSO4, pretreated S. spontaneum, K2HPO4, (NH4)2SO4 and peptone was found to be the best for maximum enzyme production by mutant Bacillus N3. 相似文献
988.
On optimal solutions of general continuous-singular stochastic control problem of McKean-Vlasov type
Lina Guenane Mokhtar Hafayed Shahlar Meherrem Syed Abbas 《Mathematical Methods in the Applied Sciences》2020,43(10):6498-6516
In this paper, we establish general necessary optimality conditions for stochastic continuous-singular control of McKean-Vlasov type equations. The coefficients of the state equation depend on the state of the solution process as well as of its probability law and the control variable. The coefficients of the system are nonlinear and depend explicitly on the absolutely continuous component of the control. The control domain under consideration is not assumed to be convex. The proof of our main result is based on the first- and second-order derivatives, with respect to measure in Wasserstein space of probability measures, and by using variational method. 相似文献
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