DMF （Damping modification factors） are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters （magnitude, epicentral dis...DMF （Damping modification factors） are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters （magnitude, epicentral distances and site conditions） on DMF for acceleration spectra was analysed. The results show that for a given period as the magnitude or distance increase, the effect of damping on the seismic response will also increase, which indicates the response reduction from the structural damping will become more efficient. In the near-field of small earthquakes, the influence of site conditions on DMF is obvious, but it does not show a consistent rule. Furthermore, the DMF corresponding to different site conditions gradually close to unity with increasing magnitude and distance. The influence of the above mentioned parameters is related to the relative attenuation of the frequency components of the ground motion. The attenuation index alone is sufficient to take into account the influence. Based on these features, this paper roDoses a formula of DMF for acceleration response spectra.展开更多
锂离子电池广泛应用于电动汽车、混合动力汽车、便携式电子设备等储能系统,但由于电荷在活性材料中传输缓慢以及活性材料易粉碎等缺点,开发同时具有高容量以及快充性能的电极材料仍然是一个极大的挑战.针对这一问题,本文通过温度调控将S...锂离子电池广泛应用于电动汽车、混合动力汽车、便携式电子设备等储能系统,但由于电荷在活性材料中传输缓慢以及活性材料易粉碎等缺点,开发同时具有高容量以及快充性能的电极材料仍然是一个极大的挑战.针对这一问题,本文通过温度调控将SnO_(2)量子点或Sn纳米团簇均匀负载在中空多孔碳纳米纤维(HPCNFs)的内部,用于制备个性化定制锂离子电池.一方面,高度互联的碳纳米纤维形成三维网络,加快了电子传输,提高了电子导电性.另一方面,中空多孔结构缩短了锂离子传输路径,促进了锂离子的快速扩散,同时,抑制了Sn和SnO_(2)的体积膨胀.由于具有较高的锂离子吸附性能以及快的离子扩散速率,低碳化温度下(450℃)合成的SnO_(2)@HPCNFs复合电极在0.1 A g^(-1)的小电流密度下具有较高的放电比容量(899.3 mA h g~(-1)).此外,由于在大的电流密度下,Sn的大孔结构能够储存更多的锂离子,以及具有较高的电子电导率,因此,高碳化温度下(850℃)制备的Sn@HPCNFs复合电极展现出优异的快充性能,同时,在5 A g^(-1)(~10 C)的高电流密度下具有238.8 mA h g^(-1)的放电容量.本文通过调控碳化温度来研究SnO_(2)和Sn电极之间的电化学行为,为构建高性能储能器件提供了新的思路.展开更多
We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficien...We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficient modulation is obtained by placing an NbN superconducting heating electrode above the TFLN waveguide.The transition of the NbN superconducting electrode between superconducting and normal states turns the heating and cooling processes from continuous to discontinuous change.Thus,the energy consumption during the modulation process is reduced proportionally.The rise/fall time of the proposed device is 22μs/15μs,which has been the fastest response time reported in TFLN thermo-optic modulators so far.The presented TO modulator can easily be used at cryogenic temperatures and has great potential for applications in cryogenic optoelectronics.展开更多
基金supported by spark program of earthquake sciences (XH15027)
文摘DMF （Damping modification factors） are used to modify elastic response spectral values corresponding to damping ratio 5% to other damping levels. The influence of seismological parameters （magnitude, epicentral distances and site conditions） on DMF for acceleration spectra was analysed. The results show that for a given period as the magnitude or distance increase, the effect of damping on the seismic response will also increase, which indicates the response reduction from the structural damping will become more efficient. In the near-field of small earthquakes, the influence of site conditions on DMF is obvious, but it does not show a consistent rule. Furthermore, the DMF corresponding to different site conditions gradually close to unity with increasing magnitude and distance. The influence of the above mentioned parameters is related to the relative attenuation of the frequency components of the ground motion. The attenuation index alone is sufficient to take into account the influence. Based on these features, this paper roDoses a formula of DMF for acceleration response spectra.
基金supported by the National Natural Science Foundation of China(51503105 and 52202256)the Natural Science Foundation of Jiangsu Province of China(BK20220612)+2 种基金the Science and Technology Development Fund,Macao SAR(0092/2019/A2 and 0035/2019/AMJ)the funds from Jiangsu University“Qinglan Project”supported by the Opening Project of Jiangsu Engineering Research Centre of Textile Dyeing and Printing for Energy Conservation,Discharge Reduction and Cleaner Production,Soochow University(SDGC2102)。
文摘锂离子电池广泛应用于电动汽车、混合动力汽车、便携式电子设备等储能系统,但由于电荷在活性材料中传输缓慢以及活性材料易粉碎等缺点,开发同时具有高容量以及快充性能的电极材料仍然是一个极大的挑战.针对这一问题,本文通过温度调控将SnO_(2)量子点或Sn纳米团簇均匀负载在中空多孔碳纳米纤维(HPCNFs)的内部,用于制备个性化定制锂离子电池.一方面,高度互联的碳纳米纤维形成三维网络,加快了电子传输,提高了电子导电性.另一方面,中空多孔结构缩短了锂离子传输路径,促进了锂离子的快速扩散,同时,抑制了Sn和SnO_(2)的体积膨胀.由于具有较高的锂离子吸附性能以及快的离子扩散速率,低碳化温度下(450℃)合成的SnO_(2)@HPCNFs复合电极在0.1 A g^(-1)的小电流密度下具有较高的放电比容量(899.3 mA h g~(-1)).此外,由于在大的电流密度下,Sn的大孔结构能够储存更多的锂离子,以及具有较高的电子电导率,因此,高碳化温度下(850℃)制备的Sn@HPCNFs复合电极展现出优异的快充性能,同时,在5 A g^(-1)(~10 C)的高电流密度下具有238.8 mA h g^(-1)的放电容量.本文通过调控碳化温度来研究SnO_(2)和Sn电极之间的电化学行为,为构建高性能储能器件提供了新的思路.
基金supported by the Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX03)the Strategic Priority Research Program(A)of the Chinese Academy of Sciences(No.XDA18040300).
文摘We propose and demonstrate a cryogenic thermo-optic(TO)modulator in x-cut thin-film lithium niobate(TFLN)with an NbN superconducting heater.Compared to a conventional metal heating electrode,a fast and energy-efficient modulation is obtained by placing an NbN superconducting heating electrode above the TFLN waveguide.The transition of the NbN superconducting electrode between superconducting and normal states turns the heating and cooling processes from continuous to discontinuous change.Thus,the energy consumption during the modulation process is reduced proportionally.The rise/fall time of the proposed device is 22μs/15μs,which has been the fastest response time reported in TFLN thermo-optic modulators so far.The presented TO modulator can easily be used at cryogenic temperatures and has great potential for applications in cryogenic optoelectronics.
