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中国与发达国家(地区)股市间的周期相关性研究 被引量:1
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作者 张瑞 《山西大同大学学报(自然科学版)》 2017年第3期16-19,34,共5页
选取上证综指、纳斯达克指数、富时100、日经225、恒生指数分别代表中国、美国、英国、日本、中国香港股市,从频域角度研究了中国与发达国家(地区)股市间的周期相关性。结果表明:中国与美国、中国香港股市的周期相关性最强,与英国次之,... 选取上证综指、纳斯达克指数、富时100、日经225、恒生指数分别代表中国、美国、英国、日本、中国香港股市,从频域角度研究了中国与发达国家(地区)股市间的周期相关性。结果表明:中国与美国、中国香港股市的周期相关性最强,与英国次之,与日本最弱;在长周期,中国股市滞后于中国香港、日本、英国股市,而在短周期,中国股市领先于中国香港、日本、英国股市;无论长周期还是短周期,中国股市均滞后于美国股市。 展开更多
关键词 叉谱 凝聚谱 交相位谱 小波分析 股票市场 周期相关性
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Analysis of the Beach Face with High-Frequency Oscillations and Dynamic Functions in the Swash Zone in the Houjiang Beach of Guangdong Province
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作者 冯砚青 陈子燊 +1 位作者 李志龙 李志强 《Marine Science Bulletin》 CAS 2008年第1期15-27,共13页
Using the data of beach face high oscillations and waves and flows of the surf zones influenced by the swells, the characteristics including beach face variation trends, trend shapes, oscillation periods, oscillation ... Using the data of beach face high oscillations and waves and flows of the surf zones influenced by the swells, the characteristics including beach face variation trends, trend shapes, oscillation periods, oscillation intensions of different profile shapes, and the characteristic relations between different stake points on the same profile were analyzed comparatively. The relations between the beach face with high oscillations erosion and sediment and the surf zone infragravity waves were also analyzed based on the cress spectrum analysis. The results showed that the swash diffluences caused by the beach cusp rhythm topography hasten the sediment transport from the beach ridge to beach paddy, and the beach face of the swash zones has the infragravity periodic oscillations, and the oscillation intensions descend from the bottom to the top of the beach face, and the infragravity waves of the surf zones have significant effect on the high-frequency variations of erosion and sediment of the beach face. 展开更多
关键词 swash zone SSA infragravity waves cross spectrum
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Ultrafast Dynamics Through Conical Intersections in 2,6-dimethylpyridine Studied with Time-resolved Photoelectron Imaging
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作者 邱学军 朱荣淑 +3 位作者 徐晏琪 布玛利亚·阿布力米提 张嵩 张冰 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期551-556,I0003,共7页
The ultrafast dynamics through conical intersections in 2,6-dimethylpyridine has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Upon absorption of 266 nm ... The ultrafast dynamics through conical intersections in 2,6-dimethylpyridine has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy. Upon absorption of 266 nm pump laser, 2,6-dimethylpyridine is excited to the S2 state with a ππ character from So state. The time evolution of the parent ion signals consists of two exponential decays. One is a fast component on a timescale of 635 fs and the other is a slow component with a timescale of 4.37 ps. Time-dependent photo- electron angular distributions and energy-resolved photoelectron spectroscopy are extracted from time-resolved photoelectron imaging and provide the evolutive information of S2 state. In brief, the ultrafast component is a population transfer from S2 to S1 through the S2/S1 conical intersections, the slow component is attributed to simultaneous IC from the S2 state and the higher vibrational levels of S1 state to So state, which involves the coupling of S2/S0 and S1/So conical intersections. Additionally, the observed ultrafast S2--+S1 transition occurs only with an 18% branching ratio. 展开更多
关键词 2 6-dimethylpyridine Photoelectron imaging Conical intersection Internalconversion Time-resolved spectroscopy
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Substituent Effects on 13C NMR and 1H NMR Chemical Shifts of CH=N in Multi-substituted Benzylideneanilines
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作者 曹朝暾 王琳艳 曹晨忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第1期45-51,I0001,共8页
Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical... Fifty-three samples of multi-substituted benzylideneanilines XArCH=NArYs (abbreviated XBAYs) were synthesized and their NMR spectra were determined. An extensional study of substituent effects on the 1H NMR chemical shifts (δH(CH=N)) and 13C NMR chemical shifts (δc(CH=N)) of the CH=N bridging group from di-substituted to multi-substituted XBAYs was made based on a total of 182 samples of XBAYs, together with the NMR data of other 129 samples of di-substituted XBAYs quoted from literatures. The results show thatthe substituent specific cross-interaction effect parameter (△(∑σ)2) plays an important role in quantifying the δc(CH=N) values of XBAYs, but it is negligible for quantifying the δH (CH=N) values; the other substituent parameters also present different influences on the δc (CH=N) and (δH (CH=N). On the whole, the contributions of X and Y to the δc (CH=N) of XBAYs are balanced, but the δH(CH=N) values of XBAYs mainly rely on the contributions of X. 展开更多
关键词 Multi-substituted benzylideneanilines Substituent effects 1H NMR chemicalshifts 13C NMR chemical shifts Substituent specific cross-interaction effect
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Supercontinuum Generation Enhanced by Cross-phase Modulation in Dispersion-flattened and Decreasing Fiber 被引量:1
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作者 XUWen-cheng XUYong-zhao YUBing-tao CUIHu CHENYong-zhu LIUSong-hao 《Semiconductor Photonics and Technology》 CAS 2005年第2期116-121,共6页
Supercontinuum spectrum generation in a dispersion-flattened and decreasing fiber with two orthogonally polarized pulses was simulated and calculated. The research results indicated that the supercontinuum spectrum ge... Supercontinuum spectrum generation in a dispersion-flattened and decreasing fiber with two orthogonally polarized pulses was simulated and calculated. The research results indicated that the supercontinuum spectrum generated by two orthogonally polarized pulses is wider and flatter than that generated by single polarized pulse due to cross-phase modulation. The cross-phase modulation effect can enhance the supercontinuum spectrum generation. When the pump power of the input pulse is lower, the enhancement of supercontinuum spectrum generation by cross-phase modulation effect is more significant. 展开更多
关键词 fiber optics supercontinuum spectrum dispersion-flattened and decreasingfiber cross-phase modulation soliton trapping
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Further Analysis of Neutron Double-Differential Cross Section of n + ^16O at 14.1 MeV and 18 MeV 被引量:1
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作者 DUAN Jun-Feng YAN Yu-Liang +2 位作者 WANG Ji-Min SUN Xiao-Jun ZHANG Jing-Shang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期701-706,共6页
By using a new reaction model for light nuclei, the double-differential cross section of total outgoing neutron with LUNF code for n+^16O reactions at En=14.1 MeV and 18 MeV have been calculated and analyzed. In this... By using a new reaction model for light nuclei, the double-differential cross section of total outgoing neutron with LUNF code for n+^16O reactions at En=14.1 MeV and 18 MeV have been calculated and analyzed. In this paper the opened reaction channels, which have contribution to emitting the neutrons, are listed in detail. To improve the fitting results the direct inelastic scattering mechanism is involved. The calculating results agree fairly well with the experimental data at E,~ = 14.1 MeV and the deviation from calculated results and experimental data in low energy region at En= 18 MeV has been analyzed. Since the possibility of 5He has been affirmed theoretically [J.S. Zhang, Sci. Chin. G 47 (2004) 137], so 5He emission from n+ ^16O reaction is taken into account, which plays an important role at the region of the outgoing neutron energy εn〈3 MeV in total outgoing neutron energy-angular spectrum. The calculated results indicate that the pre-equilibrium mechanism dominates the whole reaction processes, and the recoil effect in light nuclear reactions is essentially important. 展开更多
关键词 total outgoing neutron energy-angular spectrum light nucleus reaction
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Anti-inflammatory and Chemical Composition of Two Plants Family Asteraceae Growing in Saudi Arabia
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作者 Eman Elsharkawy Mona Alshathly Mohamed Helal 《Journal of Chemistry and Chemical Engineering》 2014年第2期157-162,共6页
The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-in... The study was designed to investigate the anti-inflammatory and composition of essential oil of two plant family Asteraceae, Achillea fragrantissima and Lactuca serriola growing under dry desert condition. The anti-inflammatory effect of volatile oil extracted by hydrodistillation of plants was studied using carrageenan induced paw edema. Essential oil (100 mg/kg) and (200 mg/kg) were tested the two plant show high inhibition after 4 h, concentration (200 mg/kg) show high inhibition than (100 mg/kg) after 4 h. Sesqui sabinene hydrate, Azuline and u-Bisabolol are the main constituents of the volatile oil were investigated by capillary GC (gas chromatography) and GC-MS (gas chromatography-mass spectrometry). The discussion shows the role of chemical compound azulene in inflammatory inhibition. 展开更多
关键词 Achillea fragrantissima Lactuca serriola ANTI-INFLAMMATORY azulene.
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Structural Dynamics of Phenyl Azide in Light-Absorbing Excited States: Resonance Raman and Quantum Mechanical Calculation Study
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作者 袁荣单 薛佳丹 郑旭明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期21-30,I0001,共11页
The excited state structural dynamics of phenyl absorbing S2(A'), S3(A'), and S6(A') states were troseopy and complete active space self-consistent and the UV absorption bands were assigned on azide (PhN3) ... The excited state structural dynamics of phenyl absorbing S2(A'), S3(A'), and S6(A') states were troseopy and complete active space self-consistent and the UV absorption bands were assigned on azide (PhN3) after excitation to the light studied using the resonance Raman specfield calculations. The vibrational spectra the basis of the Fourier transform (FT)- Raman, FT-infrared measurements, the density-functional theory computations and the normal mode analysis. The A-, B-, and C-bands resonance Raman spectra in cyclohex- ane, acetonitrile, and methanol solvents were, respectively, obtained at 273.9, 252.7, 245.9, 228.7, 223.1, and 208.8 nm excitation wavelengths to probe the corresponding structural dynamics of PhN3. The results indicated that the structural dynamics in the S2 (A'), S3(A'), and S6(A') states were significantly different. The crossing points of the potential energy surfaces, S2S1(1) and S2S1(2), were predicted to play a key role in the low-lying excited state decay dynamics, in accordance with Kasha's rule, and NT=N8 dissociation. Two decay channels initiated from the Franck-Condon region of the S2(A') state were predicted: the radiative S2,min→S0 radiative decay and the S2→S1 internal conversion through the crossing points S2S1 (1)/S2S1(2). 展开更多
关键词 Phenyl azide Structural dynamics Decay dynamics Resonance Raman spec- troscopy CASSCF calculation Curve-crossing
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Decay Dynamics of N, N-Dimethylthioacetamide in S3(ππ*) State
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作者 陈笑 薛佳丹 郑旭明 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期27-34,I0001,共9页
The decay dynamics of N, N-dimethylthioacetamide after excitation to the S3(ππ*) state was studied by using the resonance Raman spectroscopy and complete active space self- consistent field method calculations. T... The decay dynamics of N, N-dimethylthioacetamide after excitation to the S3(ππ*) state was studied by using the resonance Raman spectroscopy and complete active space self- consistent field method calculations. The UV-absorption and vibrational spectra were as- signed. The A-band resonance Raman spectra were obtained in acetonitrile, methanol and water with the laser excitation wavelengths in resonance with the first intense absorption band to probe the Franck-Condon region structural dynamics. The CASSCF calculations were carried out to determine the excitation energies and optimized structures of the lower- lying singlet states and conical intersection point. The A-band structural dynamics and the corresponding decay mechanism were obtained by the analysis of the resonance Raman in- tensity pattern and the CASSCF calculated structural parameters. The major decay channel of S3,FC (ππ*)→S3(ππ*)/S1 (nπ*)→S1(nπ*) is proposed. 展开更多
关键词 N N-Dimethylthioacetamide Structural dynamics Decay dynamics Reso-nance Raman spectrum CASSCF calculation Conical intersection
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Cross-Validation of a Mobile N20 Flux Prototype (IPNOA) Using Micrometeorological and Chamber Methods
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作者 Patricia Laville Simone Neri +3 位作者 David Continanza Luca Ferrante Vero Simona Bosco Giorgio Virgili 《Journal of Energy and Power Engineering》 2015年第4期375-385,共11页
Within a LIFE+ project IPNOA (improved flux prototype for n2o emission from agriculture), LIFE11 ENV/IT/302 is a mobile prototype was developed to evaluate at field scale N20 emissions using a fast chamber techniqu... Within a LIFE+ project IPNOA (improved flux prototype for n2o emission from agriculture), LIFE11 ENV/IT/302 is a mobile prototype was developed to evaluate at field scale N20 emissions using a fast chamber technique. Main challenge was to develop a mobile system capable of moving on various field surfaces, equipped with very reliable N20 gas analyser (Los Gatos Research Inc.), electrically autonomous (with batteries) and enough robust to face up to field conditions. In this paper, we report the major features of this prototype studied during two field campaigns. The N20 flux IPNOA prototype was compared with other methodological implementations: first, during an INGOS (integrated non-CO2 greenhouse gas observing systems) campaign on a grazed grassland at Easter Bush (Scotland) by Eddy correlation method, and then after on an arable crop at Grignon (France) using automatic and manual chambers fitted with QC-TILDAS (Quantum Cascade Tunable Infrared Laser Differential Absorption Spectrometer, Aerodyne Research Inc.), with the 46C model of thermo-instrument analyser or with a GC (gas chromatography) analysis. 展开更多
关键词 Monitoring device nitrous oxide inventory agricultural managements steady state chamber.
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Quantitative deconvolution of autocorrelations and cross correlations from two-dimensional lifetime decay maps in fluorescence lifetime correlation spectroscopy 被引量:2
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作者 Shanshan Gao Menghua Cui +3 位作者 Ruiru Li Ling Liang Ying Liu Liming Xie 《Science Bulletin》 SCIE EI CAS CSCD 2017年第1期9-15,共7页
Fluorescence correlation spectroscopy (FCS) is a widely used method for measuring molecular diffusion and chemical kinetics. However, when a mixture of fluorescent species is taken into account, the conven- tional F... Fluorescence correlation spectroscopy (FCS) is a widely used method for measuring molecular diffusion and chemical kinetics. However, when a mixture of fluorescent species is taken into account, the conven- tional FCS method has limitations in extracting autocorrelations for different species and cross correla- tions between different species. Recently developed fluorescence lifetime correlation spectroscopy (FLCS) based on time-tagged time-resolved (TITR) photon recording, which can record the global and micro arrival time for each individual photon, has been used to discriminate different species according to fluorescence lifetime. Here, based on two-dimensional lifetime decay maps constructed from TITR photon stream, we have developed a quantitative lifetime-deconvolution FCS model (LDFCS) to extract precise chemical rates for chemical conversions in multi-species systems. The key point of LDFCS model is separation of different species according to the global distribution of fluorescence lifetime and then deconvolution of autocorrelations and cross-correlations from the two-dimensional lifetime decay maps constructed bv the micro arrival times of photon pairs at each delay time. 展开更多
关键词 Fluorescence lifetime Fluorescence correlation spectroscopy Cross correlation
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The improvement of cross-calibration of IIM data and band selection for FeO inversion 被引量:4
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作者 WANG Chao WU YunZhao +1 位作者 SHI RunHe GAO Wei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2216-2225,共10页
Chang’E-1(CE-1)Interference Imaging Spectrometer(IIM)dataset suffers from the weak response in the near infrared(NIR)bands,which are the important wavelength for retrieving the minerals and elements of the Moon.In th... Chang’E-1(CE-1)Interference Imaging Spectrometer(IIM)dataset suffers from the weak response in the near infrared(NIR)bands,which are the important wavelength for retrieving the minerals and elements of the Moon.In this paper,the cross-calibration was implemented to the IIM hyperspectral data for improving the weak response in NIR bands.The results show that the cross-calibrated IIM spectra were consistent to the Earth-based telescopic spectra,which suggests that the cross-calibration yields acceptable results.For further validating the influence of the cross-calibration on the FeO inversion and searching the optimal bands to retrieve lunar FeO contents,four band selection schemes were designed to retrieve FeO using the original and cross-calibrated IIM spectra.By comparing the distribution patterns and histograms of the IIM derived FeO contents with the Clementine derived FeO,the IIM 891 nm band after cross-calibration showed a higher accuracy in the FeO inversion,hence most useful for lunar FeO inversion. 展开更多
关键词 IIM CROSS-CALIBRATION band selection FEO MOON
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A tension insensitive PbS fiber temperature sensor based on Sagnac interferometer
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作者 付兴虎 张江鹏 +4 位作者 杨凯丽 董艳华 文建湘 付广伟 毕卫红 《Optoelectronics Letters》 EI 2017年第2期135-137,共3页
In this paper, a tension insensitive Pb S fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between t... In this paper, a tension insensitive Pb S fiber temperature sensor based on Sagnac interferometer is proposed and demonstrated. The sensing mechanism of tension and temperature is analyzed. The relationships between the interference spectrum, temperature and tension are analyzed, respectively. The experimental temperature range is 36—70 °C. The experimental results show that the interference spectrum is red shifted, and its sensitivity is 53.89 pm/°C. In tension experiment, the tension range is 0—1 400 με. The experimental results show that there is no wavelength shift in the interference spectrum. The sensor is immune to tension cross-sensitivity compared with other sensors. It can be used for temperature testing in aerospace, chemistry and pharmacy. 展开更多
关键词 interferometer insensitive pharmacy aerospace shifted temper schematic Bragg grating coupler
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