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21.
铸膜液的溶剂体系(溶剂和非溶剂)对不对称膜形态的形成有重要作用。为了探索溶剂和透气性间的关系,本文考虑到了制备BCA梯度密度不对称膜的各种溶剂的一系列物理参数,得到了一些定性结果,并指出了更全面、明确、解释两者关系的研究方向。 相似文献
22.
基于委托-代理理论的Mirrlees-Holmstrom模型,对信息不对称条件下激励方案的设计和选择作了分析和比较,结果表明,不同激励方案的激励效果取决于不确定性的相关系数,提出了在管理实践中还要结合方案的可操作性以及确定相应的激励机制。 相似文献
23.
We proposed two whispered speech enhancement methods based on asymmetric cost functions in this paper to deal with the amplification and attenuation distortions of whispered speech distinctively.The modified Itakura-Saito(MIS)distance function provides more penalties to speech amplification distortion,whereas the Kullback-Leibler(KL)divergence function gives more penalties to speech attenuation distortion.The experimental results show that the MIS function based method achieves significant improvement of intelligibility in contrast to the conventional speech enhancement algorithms when the signal-to-noise ratio(SNR)falls below-6 dB,whereas the KL function based one achieves the similar result as the minimum mean square error(MMSE)speech enhancement method.The results show that the effects of the amplification and attenuation distortions on the intelligibility of the enhanced whisper are different,where larger attenuation distortion may result in better intelligibility of speech with low SNR.However,the attenuation distortion has small effects on intelligibility of speech with high SNR. 相似文献
24.
In this paper, we theoretically investigate the asymmetric molecular high-order harmonic emission and the attosecond X-ray pulse generation when the asymmetric molecular HeH2+ ion is exposed to an intense chirped pulse. It is found that the molecular harmonics are strongly dependent on the internuclear distance R as well as the chirp parameter, showing a smooth and intense harmonic plateau at R = 8.0 a.u. and β = 0.4. Further, by adding a subharmonic controlling pulse with the optimised conditions, a supercontinuum with a bandwidth of 602 eV can be obtained. Finally, by properly superposing the selected harmonics in the supercontinuum region, a series of isolated X-ray pulses with durations of sub-80 as are directly generated. 相似文献
25.
Facile Construction of 3D Reduced Graphene Oxide Wrapped Ni3S2 Nanoparticles on Ni Foam for High‐Performance Asymmetric Supercapacitor Electrodes 下载免费PDF全文
Jiqiu Qi Yuan Chang Yanwei Sui Yezeng He Qingkun Meng Fuxiang Wei Yulong Zhao Yunxue Jin 《Particle & Particle Systems Characterization》2017,34(12)
3D reduced graphene oxide (rGO)‐wrapped Ni3S2 nanoparticles on Ni foam with porous structure is successfully synthesized via a facile one‐step solvothermal method. This unique structure and the positive synergistic effect between Ni3S2 nanoparticles and graphene can greatly improve the electrochemical performance of the NF@rGO/Ni3S2 composite. Detailed electrochemical measurements show that the NF@rGO/Ni3S2 composite exhibits excellent supercapacitor performance with a high specific capacitance of 4048 mF cm?2 (816.8 F g?1) at a current density of 5 mA cm?2 (0.98 A g?1), as well as long cycling ability (93.8% capacitance retention after 6000 cycles at a current density of 25 mA cm?2). A novel aqueous asymmetric supercapacitor is designed using the NF@rGO/Ni3S2 composite as positive electrode and nitrogen‐doped graphene as negative electrode. The assembled device displays an energy density of 32.6 W h kg?1 at a power density of 399.8 W kg?1, and maintains 16.7 W h kg?1 at 8000.2 W kg?1. This outstanding performance promotes the as‐prepared NF@rGO/Ni3S2 composite to be ideal electrode materials for supercapacitors. 相似文献
26.
Network dynamics and its relationships to topology and coupling structure in excitable complex networks 下载免费PDF全文
All dynamic complex networks have two important aspects, pattern dynamics and network topology. Discovering different types of pattern dynamics and exploring how these dynamics depend or/network topologies are tasks of both great theoretical importance and broad practical significance. In this paper we study the oscillatory behaviors of excitable complex networks (ECNs) and find some interesting dynamic behaviors of ECNs in oscillatory probability, the multiplicity of oscillatory attractors, period distribution, and different types of oscillatory patterns (e.g., periodic, quasiperiodic, and chaotic). In these aspects, we further explore strikingly sharp differences among network dynamics induced by different topologies (random or scale-free topologies) and different interaction structures (symmetric or asymmetric couplings). The mechanisms behind these differences are explained physically. 相似文献
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28.
This review deals with the high-throughput field in surface catalysis and adsorption. Special focus is placed on advanced
methods for knowledge discovery such as density functional theory (DFT) simulations. An inventory of successful cases on several
elements in Group I-B and VIII is reported, including the relevant data and knowledge management, which are very important
in chemical industry, fuel cell, and environment protection, for both scientific and economical reasons.
相似文献
29.
MI Ai-Jun ZUO Wei LI Zeng-Hua Umberto Lombardo 《理论物理通讯》2009,51(6):1113-1116
The 3 P F2 superfluidity of neutron and proton is investigated in isospin-asymmetric nuclear matter within the Brueckner-Hartree-Fock approach and the BCS theory by adopting the Argonne V14 and the Argonne V18 nucleonnucleon interactions. We find that pairing gaps in the 3PF2 channel predicted by adopting the AV14 interaction are much larger than those by the AV18 interaction. As the isospin-asymmetry increases, the neutron 3 pF2 superfluidity is found to increase rapidly, whereas the proton one turns out to decrease and may even vanish at high enough asymmetries. As a consequence, the neutron 3pF2 superfluidity is much stronger than the proton one at high asymmetries and it predominates over the proton one in dense neutron-rich matter. 相似文献
30.