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21.
Fang Tao Chen Xiuting Wang Miao Wang Yanan Liao Lixia Li Bin 《Research on Chemical Intermediates》2020,46(12):5459-5477
Research on Chemical Intermediates - In recent years, how to improve photocatalytic performance under visible light has become one of the research hot topics. The nano-TiO2 particles were... 相似文献
22.
Fang Xu Longjian Xie Akira Yoneda Nicolas Guignot Andrew King Guillaume Morard 《高压研究》2020,40(2):257-266
ABSTRACTTiC-MgO composite was developed as a heating element for X-ray study in the multi-anvil high pressure apparatus. We synthesized TiC-MgO blocks (50–70 wt.% of TiC) by compression in a cold isostatic press followed by baking in a gas flow furnace. Heaters of tubular shape were manufactured from the synthesized blocks either by lathe or numerically controlled milling machine. The so-produced heating elements have been proved to generate temperatures up to 2250?K at 10?GPa, condition where classical graphite heaters are not suitable anymore due to graphite-diamond transition. These new heaters have been successfully used for in situ X-ray radiography and diffraction measurements on liquid Fe alloys, exploiting excellent X-ray transparency. 相似文献
23.
提出了一类新的相对性区域创新指数,并采用世界专利申请数据对其进行了具体计算.基于区域创新同经济发展水平之间的超线性关系,该指数消除了经济发展水平对创新能力的影响,可以实现对不同发展水平的经济体之间进行有效的创新能力横纵对比.该创新指数尽管极其简单,却揭示出一系列迥异于传统认知的现象,例如中国大陆地区的技术创新能力在1980年代就已经位居世界前列.采用该指数,不但可以在较高水平上解释世界各国的经济增长,还发现它同经济增长率之间的相关性存在一个20年的经济周期.这些结果显示,该指数作为一个单一性指标,以极小的数据依赖就实现了较高程度的解释性,不但重新定位了世界各经济体的创新能力,对深入理解创新同经济发展之间的关系提供了新的角度,而且暗示着这类相对性经济指标的发展潜力与应用空间. 相似文献
24.
Gzal M. Fang B. Vakakis A. F. Bergman L. A. Gendelman O. V. 《Nonlinear dynamics》2020,101(4):2087-2106
Nonlinear Dynamics - This paper describes a rapid and efficient nonlinear non-resonance mechanism for low-to-high-frequency energy scattering, which is referred to as intermodal targeted energy... 相似文献
25.
本文从理论上研究了在双色频率梳激光场驱动下多光子谐波辐射光谱中的相位突变现象。我们利用Floquet理论非微扰地模拟了频率梳激光场与原子分子等量子系统的相互作用过程。谐波辐射信号是多光子偶极跃迁相干叠加的结果,通过调节频率梳激光场间的相对相位,可以相干地控制谐波辐射信号的强度。通过对谐波信号进行傅里叶变换,可以提取不同跃迁路径的相对相位信息。我们通过改变频率梳组激光场的强度和频率组分实现多光子跃迁频率,让其跨越共振跃迁频率时,谐波相位会发生突变。从而可以观测超强激光场驱动下量子系统共振跃迁频率的斯塔克能移。 相似文献
26.
We demonstrate a harmonically pumped femtosecond optical parametric oscillator(OPO)laser using a frequency-doubled mode-locked Yb:KGW laser at a repetition rate of 75.5 MHz as the pump laser.Based on a bismuth borate nonlinear crystal,repetition rates up to 1.13 GHz are realized,which is 15 times that of the pump laser.The signal wavelength is tunable from 700 nm to 887 nm.The maximum power of the signal is 207 m W at the central wavelength of 750 nm and the shortest pulse duration is 117 fs at 780 nm.The beam quality(M^2 factor)in the horizontal and vertical directions of the output beam are 1.077 and 1.141,respectively. 相似文献
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29.
Elastic,dielectric, and piezoelectric characterization of 0.92Pb(Zn1/3Nb2/3)O3-0.08PbTiO3 single crystal by Brillouin scattering 下载免费PDF全文
In this paper,a complete set of elastic,piezoelectric,and dielectric constants of high-quality tetragonal poled0.92Pb(Zn_(1/3)Nb_(2/3))O_3-0.08PbTiO_3 single crystal grown by the modified flux method is determined using high-resolution Brillouin scattering.A comparison is made between the results obtained by a hybrid method combining ultrasonic and resonant techniques and the results obtained by the Brillouin scattering.The elastic,piezoelectric,and dielectric constants obtained by the two methods are similar.The Brillouin spectrum consists of one longitudinal and two transverse acoustic phonon modes,and the variations of the Brillouin shifts,the full widths at half maximum,and the scattering intensities of these modes with scattering angle 9 are investigated.In particular,the transverse acoustic phonon mode at the lowfrequency becomes markedly soft from 28.2 GHz to 18.4 GHz and broadens gradually with the increase of θ,while its intensity decreases gradually as compared with that of the original one.The possible origins of the results are discussed. 相似文献
30.
Interplay of Hole Transfer and Host–Guest Interaction in a Molecular Dyad and Triad: Ensemble and Single‐Molecule Spectroscopy and Sensing Applications 下载免费PDF全文
Dr. Xiangyang Wu Dr. Fang Liu Dr. Kym L. Wells Serena L. J. Tan Prof. Dr. Richard D. Webster Prof. Dr. Howe‐Siang Tan Prof. Dr. Dawei Zhang Prof. Dr. Bengang Xing Prof. Dr. Edwin K. L. Yeow 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(8):3387-3398
A new molecular dyad consisting of a Cy5 chromophore and ferrocene (Fc) and a triad consisting of Cy5, Fc, and β‐cyclodextrin (CD) are synthesized and their photophysical properties investigated at both the ensemble and single‐molecule levels. Hole transfer efficiency from Cy5 to Fc in the dyad is reduced upon addition of CD. This is due to an increase in the Cy5‐Fc separation (r) when the Fc is encapsulated in the macrocyclic host. On the other hand, the triad adopts either a Fc‐CD inclusion complex conformation in which hole transfer quenching of the Cy5 by Fc is minimal or a quasi‐static conformation with short r and rapid charge transfer. Single‐molecule fluorescence measurements reveal that r is lengthened when the triad molecules are deposited on a glass substrate. By combining intramolecular charge transfer and competitive supramolecular interaction, the triad acts as an efficient chemical sensor to detect different bioactive analytes such as amantadine hydrochloride and sodium lithocholate in aqueous solution and synthetic urine. 相似文献