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31.
The CO2-broadened water coefficients (half-widths, line shifts, and temperature dependence of the widths) are predicted using a fully complex Robert-Bonamy formulation for the 937 allowed and forbidden perpendicular type transitions of (000)-(000) between 200 and 900 cm−1 in order to facilitate atmospheric remote sensing of Mars and Venus. In addition, empirical Lorentz line widths and pressure-induced frequency-shifts of CO2-broadened H216O are obtained at room temperature for 257 perpendicular transitions of the (010)-(000) fundamental. For this, calibrated spectra recorded at 0.0054 cm−1 resolution are measured assuming Voigt line shapes. For transitions between 1287 and 1988 cm−1 with rotational quanta up to J = 13 and Ka = 6, the widths vary from 0.045 to 0.212 cm−1 atm−1 at 300 K; the pressure-shifts are quite large and range from −0.0386 to +0.0436 cm−1 atm−1. For the (010)-(000) band, the RMS and mean observed and calculated differences for CO2-broadened H2O half-widths are 12% and −1.9%, respectively, while the RMS and mean ratios of the observed and calculated pressure-induced shift coefficients are 1.6 and 0.79, respectively. For pairs of transitions involving Ka = 0 and 1, such as 20 2 ← 31 3 and 31 3 ← 20 2, both the calculated and observed pressure induced shifts in positions are opposite in sign and often similar in magnitude. The data are too limited to characterize vibrational dependencies of the widths, however.  相似文献   
32.
This paper reports that the blend films of poly (2-methoxy-5-(2'-ethyl-hexyloxy)-p-phenylene vinylene) (MEH-PPV) and N,N'-bis(1-ethylpropyl)-3,4: 9,10-perylene bis (tetracarboxyl diimide) (EP-PDI) with the weight ratio of 1:2.5 have been prepared by spin-coating from chloroform (CF) and chlorobenzene (CB) solutions respectively. The absorption spectra and the morphology of the blend films show that large crystal-like EP-PDI aggregates are formed in film prepared from CB solution, which corresponds to a new absorption shoulder near 590nm, while there is no shoulder around 590\,nm in the UV--Vis absorption spectra of the blend film from CF solution. The electric-field dependence spectra of the photocurrent generation quantum yield of the film from CB solution shows that at weak electric field the EP-PDI aggregates act as more efficient sensitizers, but at strong electric field the quantum yields become almost invariable over the entire spectral range no matter what the state of EP-PDI, monomer or aggregate. At strong electric field, the photocurrent generation yields of both films from CF and CB solution saturate and their yield spectra become spectrally similar, mentioning that at strong electric field the photoexcitons dissociate efficiently and the free charges are collected by the electrodes almost completely.  相似文献   
33.
Temperature dependence of the properties of strong-coupling bipolaron in a quantum dot (QD) is studied based on the Lee-Low-Pines-Huybrechts variational method and quantum statistical theory. Results of the numerical calculation show that the vibration frequency as well as the absolute value of the induced potential and the effective potential all increase with increasing coupling strength and temperature, respectively, and they also increase with decreasing relative distance of electrons. The bipolarons are closer and more stable when the temperature is higher and coupling strength is larger. The influence of radius of QD and dielectric constant ratio on the effective potential is little.  相似文献   
34.
最近实验上发现高能粒子反应末态强子多重数与其质量之间满足简单普适经验公式.计算了e+e湮没与pp(p)反应过程的直生介子与重子多重数,与经验公式中的参数完全一致.对经验公式中与反应能量有关的参数给出合理解释,并讨论了质量普适关系的原因.  相似文献   
35.
本文报道了BR水溶性Raman光谱的温度相关性及吸收光谱变化。讨论了导致光谱变化的热诱导引起的结构变化。  相似文献   
36.
Our paper is concerned with some basic theorems for microstretch thermoelastic materials. By using the Lagrange identity, we prove the uniqueness theorem and some continuous dependence theorems without recourse to any energy conservation law, or to any boundedness assumptions on the thermoelastic coefficients. Moreover, we avoid the use of positive definiteness assumptions on the thermoelastic coefficients.  相似文献   
37.
The pressure dependence of thelo-to phonons in InAs has been investigated by Raman scattering using the diamond anvil cell. Indium arsenide transforms, presumably to the rock-salt structure at 70±1 kbar. The mode Grüneisen parameters for thelo-to phonons are γ lo =0.99±0.03, γ to =1.2±0.03 respectively. The effective charge,e* T , for InAs decreases slightly with pressure and this trend is in accordance with the behaviour of other III–V zinc blende structured semiconductors: The structural phase transition is discussed in the light of theoretical calculations for phase stability of III–V compounds, as well as recent high pressure x-ray diffraction studies.  相似文献   
38.
The pressure dependence of the direct and indirect bandgap of epitaxial In0.52Al0.48As on InP(001) substrate has been measured using photoluminescence up to 92 kbar hydrostatic pressure. The bandgap changes from Γ toX at an applied pressure of ∼ 43 kbar. Hydrostatic deformation potentials for both the Γ andX bandgaps are deduced, after correcting for the elastic constant (bulk modulus) mismatch between the epilayer and the substrate. For the epilayer we obtain and+(2.81±0.15)eV for the Γ andX bandgaps respectively. From the pressure dependence of the normalized Γ-bandgap photoluminescence intensity a Γ-X lifetime ratio, (τΓ X ), of 4.1×10−3 is deduced.  相似文献   
39.
Asymptotic normality of the solutions of the initial-value problems for multidimensional Burgers' equation with weakly dependent possible non-Gaussian initial condition is proved.  相似文献   
40.
本文用显微拉曼谱仪在波长为785 nm的激光激发下,对Y2O3:Eu陶瓷在温度83-473 K间进行了系统的变温拉曼实验研究。实验发现Y2O3:Eu的一些振动模在低温下没有出现,只有当温度达到一定值之后才可以被观察到,分析表明这是由于温度变化引起的简并振动模式分裂。此外,Y2O3:Eu的拉曼峰位、半高全峰宽(FWHM)也是温度的非线性函数,且不同的拉曼峰遵循不同的函数关系,本文分析这是由于晶格的各向异性导致的。  相似文献   
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