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991.
992.
A 1 × 4 polarization and wavelength independent optical power splitter is reported. This device is based on a novel wide-angle low-loss Y-junction structure which can give a theoretical TE junction excess loss of 0.26 dB at a branching angle of 16°. To the best of our knowledge, it is so far the lowest reported loss at such a large angle. The detailed design of the device and its fabrication are described. Our experimental results show the measured TE excess loss to be 1.2 dB and TM excess loss 1.8 dB for the whole splitter over the wavelength between 1.47 μm and 1.57 μm. 相似文献
993.
Hyun Woo Chung 《Applied Surface Science》2006,252(13):4545-4548
New ferroelectric Pb(Zr,Ti)O3-Pb(Mn,W,Sb,Nb)O3 (PZT-PMWSN) thin film has been deposited on a Pt/Ti/SiO2/Si substrate by pulsed laser deposition. Buffer layer was adopted between film and substrate to improve the ferroelectric properties of PZT-PMWSN films. Effect of a Pb(Zr0.52Ti0.48)O3 (PZT) and (Pb0.72La0.28)Ti0.93O3 (PLT) buffer layers on the stabilization of perovskite phase and the suppression of pyrochlore phase has been examined. Role of buffer layers was investigated depending on different types of buffer layer and thickness. The PZT-PMWSN thin films with buffer layer have higher remnant polarization and switching polarization values by suppressing pyrochlore phase formation. The remnant polarization, saturation polarization, coercive field and relative dielectric constant of 10-nm-thick PLT buffered PZT-PMWSN thin film with no pyrochlore phase were observed to be about 18.523 μC/cm2, 47.538 μC/cm2, 63.901 kV/cm and 854, respectively. 相似文献
994.
995.
996.
997.
Wenhu Han Wenkai Liang Cheng Wang Jennifer X. Wen Chung K. Law 《Proceedings of the Combustion Institute》2021,38(3):3575-3583
This work studies numerically the spontaneous initiation and sustenance of a detonation wave from a hot spot with a nonuniform initial temperature embedded within an H2O2 mixture with and without O3 addition. For the case with either no or just a small amount of O3 addition, a weak reaction wave is auto-ignited at the hot spot, accelerates and then transitions to a pulsating detonation, which propagates along the temperature gradient and quenches as it runs into the cold fresh mixture. However, with increasing O3 addition, the possibility of sustenance of a developing detonation within the gradient is significantly enhanced as it enters the cold mixture. Furthermore, the reduced induction time by O3 addition leads to earlier appearance of the spontaneous reaction wave and detonation formation in the cold mixture, demonstrating that quenching of the detonation is largely related to the instability property of the mixture because the shortened induction time reduces substantially the instability. It is also noted that, for 5%O3 addition, a low-temperature flame produced by the O3 reactions is present in front of the spontaneous reaction wave, inducing a local pressure wave, which facilitates spontaneous initiation and sustains the detonation entering the cold mixture. Moreover, O3 addition renders the critical temperature to induce the minimum spontaneous wave speed higher than the crossover temperature, while they are very close for the case without O3. 相似文献
998.
999.
卢洪洋 刘小雨 丁兵 刘忠 P.Doornenbal A.Obertelli S. M.Lenzi P. M.Walker L. X.Chung B. D.Linh G.Authelet H.Baba D.Calvet F.Chateau A.Corsi A.Delbart J. M.Gheller A.Gillibert T.Isobe V.Lapoux M.Matsushita S.Momiyama T.Motobayashi M.Niikura F.Nowacki H.Otsu C.Péron A.Peyaud E. C.Pollacco J. Y.Roussé H.Sakurai M.Sasano Y.Shiga S.Takeuchi R.Taniuchi T.Uesaka H.Wang K.Yoneda 《原子核物理评论》2020,37(3):548-553
利用放射性束68Fe轰击液氢靶引起的敲出反应,研究了极端丰中子核63,65,67Mn的激发态,指认了它们的自旋宇称,建立了这三个原子核的能级纲图。纲图包含11/2–、9/2–和 7/2– 三个激发态以及$5/2_{\rm{g.s.}}^{-}$ 基态,它们由三条$\Delta I \!=\! 1$ 的$\gamma$ 跃迁连接。这种能级结构与$K \!=\! 5/2$ 时强耦合转动带的特征一致。使用改进的LNPS有效相互作用(LNPSm)的大规模壳模型计算能很好地重现观测到的能级。计算表明,65,67Mn的低位激发态都主要包含处于$4p{\text -}4h$ 的中子组态和$1p{\text -}1h$ 的质子组态。基于实验结果发现,在吸积中子星壳中,与质量数$A \!=\! 63$ 相关的Urca中微子冷却效果比预期的要强很多,而$A \!=\! 65, 67$ 的冷却效果比预期的更弱。 相似文献
1000.
The N-terminal fragment of prohormone brain natriuretic peptide (NT-proBNP) is a commonly used biomarker for the diagnosis of congestive heart failure, although its biological function is not well known. NT-proBNP exhibits heavy O-linked glycosylation, and it is quite difficult to develop an antibody that exhibits glycosylation-independent binding. We developed an antibody that binds to the recombinant NT-proBNP protein and its deglycosylated form with similar affinities in an enzyme immunoassay. The epitope was defined as Gly63–Lys68 based on mimetic peptide screening, site-directed mutagenesis and a competition assay with a peptide mimotope. The nearest O-glycosylation residues are Thr58 and Thr71; therefore, four amino acid residues intervene between the epitope and those residues in both directions. In conclusion, we report that an antibody reactive to Gly63–Lys68 of NT-proBNP exhibits O-glycosylation-independent binding. 相似文献