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11.
Ding Hanyi Zhang Guangzhao 《International Journal of Infrared and Millimeter Waves》1993,14(8):1657-1666
A method for measuring complex permittivity based on an electric-field cross-correlation Fourier transform spectrometer was proposed. Its principle can be extended over the whole microwave region. Two typical solid media, teflon and plexigrass, and a kind of sand were measured in 8mm-wave region by the method. The results show that this method has potentialities to perform accurate permittivity measurements.Supported by Foundation of Specialities Opened to Doctorate Study 相似文献
12.
Upper bound for the time derivative of entropy for a dynamical system driven by coloured cross-correlated white noises 下载免费PDF全文
It is shown how the cross-correlation time and strength of coloured cross-correlated white noises can set an upper bound for the time derivative of entropy in a nonequilibrium system. The value of upper bound can be calculated directly based on the Schwartz inequality principle and the Fokker--Planck equation of the dynamical system driven by coloured cross-correlated white noises. The present calculations can be used to interpret the interplay of the dissipative constant and cross-correlation
time and strength of coloured cross-correlated white noises on the upper bound. 相似文献
13.
Ranajeet Ghose James H. Prestegard 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1997,128(2):138-143
The effects of cross-correlation between Curie spin–nuclear dipole and nuclear dipole–nuclear dipole interactions on the linewidths and resonance frequencies of the individual lines of anAXmultiplet in paramagnetic systems have been calculated. The implication of the relaxation-induced frequency shift of the lines (dynamic frequency shift) for the accurate measurement of residual dipolar couplings in field-oriented systems has been discussed. Our simulations indicate that these effects may play a role in the precise measurement of residual dipolar couplings in systems which belong to the small and intermediate tumbling regime, i.e., correlation times less than 5 ns. 相似文献
14.
ZHANG Li CAO Li WU Da-Jin 《理论物理通讯》2006,46(4):651-655
A two-dimensional single-mode laser model with cross-correlation between the real and imaginary parts of the colored quadric pump noise is investigated. A novel laser amplitude Langevin equation is obtained, in which the cross-correlation λp between the real and imaginary parts of the pump noise appears. The mean, variance, and skewness of first-passage-time are calculated. It is shown that the mean, variance, and skewness of first-passage-time are strongly affected by λp. 相似文献
15.
The cluster-galaxy cross-correlation and the average infall velocity around cluster for the tilted CDM models, the hot-cold
mixed dark matter models (MDM) and theA CDM models are calculated. And it is found that the prediction of the cluster-galaxy cross-correlation of theA CDM models with ΩA=0.9, ΩC=0.1,h=1,b = 1 or 2 is much higher than that of observation for the radius larger than 10 h−1 Mpc (H0 = 100 h.kms−1Mpc−1), and the other models are compatible with the observation on the scale of (3–20) h− Mpc. The results can be used to compare with new observations to restrict the nature of the dark matter and the biasing factor.
Project supported by the National Natural Science Foundation of China (Grant No. 19733001). 相似文献
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Finding the critical factor and possible “Newton’s laws” in financial markets has been an important issue. However, with the development of information and communication technologies, financial models are becoming more realistic but complex, contradicting the objective law “Greatest truths are the simplest.” Therefore, this paper presents an evolutionary model independent of micro features and attempts to discover the most critical factor. In the model, information is the only critical factor, and stock price is the emergence of collective behavior. The statistical properties of the model are significantly similar to the real market. It also explains the correlations of stocks within an industry, which provides a new idea for studying critical factors and core structures in the financial markets. 相似文献
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The ultrafast vibrational phase relaxation of O–H stretch in bulk water is investigated in molecular dynamics simulations. The dephasing time (T2) of the O–H stretch in bulk water calculated from the frequency fluctuation time correlation function (Cω(t)) is in the range of 70–80 femtosecond (fs), which is comparable to the characteristic timescale obtained from the vibrational echo peak shift measurements using infrared photon echo [W.P. de Boeij, M.S. Pshenichnikov, D.A. Wiersma, Ann. Rev. Phys. Chem. 49 (1998) 99]. The ultrafast decay of Cω(t) is found to be responsible for the ultrashort T2 in bulk water. Careful analysis reveals the following two interesting reasons for the ultrafast decay of Cω(t). (A) The large amplitude angular jumps of water molecules (within 30–40 fs time duration) provide a large scale contribution to the mean square vibrational frequency fluctuation and gives rise to the rapid spectral diffusion on 100 fs time scale. (B) The projected force, due to all the atoms of the solvent molecules on the oxygen (FO(t)) and hydrogen (FH(t)) atom of the O–H bond exhibit a large negative cross-correlation (NCC). We further find that this NCC is partly responsible for a weak, non-Arrhenius temperature dependence of the dephasing rate. 相似文献
20.
Mingqi Sun Jiaqi Meng Weier Bao Dr. Ming Liu Xiaojuan Li Zicheng Wang Zhecheng Ma Prof. Dr. Xuefei Wang Prof. Dr. Zhiyuan Tian 《Chemphyschem》2023,24(6):e202200716
Room temperature phosphorescence (RTP) materials are characterized with emission after removing the excitation source. Such long-lived emission feature possesses great potential in biological fluorescence imaging because it enables a way regarding temporal dimension for separating the interference of autofluorescence and common noises typically encountered in conventional fluorescence imaging. Herein, we constructed a new type of mesoporous silica nanoparticles (MSNs)-based composite nanoparticles (NPs) with dual-color long-lived emission, namely millisecond-level green phosphorescence and sub-millisecond-level delayed red fluorescence by encapsulating a typical RTP dye and Rhodamine dye in the cavities of the MSNs with the former acting as energy donor (D) while the latter as acceptor (A). Benefiting from the close D-A proximity, energy match between the donor and the acceptor and the optimized D/A ratio in the composite NPs, efficient triplet-to-singlet Förster resonance energy transfer (TS-FRET) in the NPs occurred upon exciting the donor, which enabled dual-color long-lived emission. The preliminary results of dual-color correlation imaging of live cells based on such emission feature unequivocally verified the unique ability of such NPs for distinguishing the false positive generated by common emitters with single-color emission feature. 相似文献