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111.
V. G. Arakcheev V. N. Bagratashvili A. A. Valeev V. B. Morozov A. N. Olenin V. K. Popov D. V. Yakovlev 《Russian Journal of Physical Chemistry B, Focus on Physics》2009,3(7):1062-1066
Coherent anti-Stokes Raman scattering spectra measured within the Q-branch of the vibrational transition ν1 are used to gain insights into the state of carbon dioxide molecules in nanopores of Vycor™ glass at room temperature (20.5°C)
and a subcritical temperature of 30.5°C and gas pressures up to the saturation point P
sat for each temperature. Along with the main spectral component, belonging to gaseous CO2 molecules, the spectra recorded at pressures close to P
sat feature a second (low-frequency) component. The second component is associated with the contribution from the CO2 molecules trapped inside pores. A spectral deconvolution with account for the interference of these two bands makes it possible
to estimate the spectral characteristics of the second (low-frequency) component at each temperature. At 20.5°C, the bandwidth
of the low-frequency component decreases with CO2 pressure, a behavior that can be explained by the transition of CO2 from the adsorbed to the condensed state in the pore. At the subcritical temperature of 30.5°C, the spectral width of the
second component is pressure-independent and close to the value measured in the bulk of the supercritical fluid, a result
likely associated with a low-temperature shift of the critical point of the substance trapped in nanopores. 相似文献
112.
It is shown that the effect of dissipative and gyroscopic forces on a certain class of potential linear time-varying system differs considerably from the effect of these forces on a time-invariant system. Examples are considered. In the first of these, the equations of motion of a disk, attached to a rotating weightless elastic shaft, are investigated, taking external friction into account. The results obtained are compared with the results obtained previously by others when considering this problem. In the second example, certain problems of the stability of rotation of a Lagrange top on a base subjected to vertical harmonic vibrations are investigated. 相似文献
113.
A. D. Mironov A. Yu. Morozov A. V. Sleptsov 《Theoretical and Mathematical Physics》2013,177(2):1435-1470
In the planar limit of the’ t Hooft expansion, the Wilson-loop vacuum average in the three-dimensional Chern-Simons theory (in other words, the HOMFLY polynomial) depends very simply on the representation (Young diagram), HR(A|q)|q=1 = (σ1(A)|R|. As a result, the (knot-dependent) Ooguri-Vafa partition function $\sum\nolimits_R {H_{R\chi R} \left\{ {\bar pk} \right\}}$ becomes a trivial τ -function of the Kadomtsev-Petviashvili hierarchy. We study higher-genus corrections to this formula for HR in the form of an expansion in powers of z = q ? q?1. The expansion coefficients are expressed in terms of the eigenvalues of cut-and-join operators, i.e., symmetric group characters. Moreover, the z-expansion is naturally written in a product form. The representation in terms of cut-and-join operators relates to the Hurwitz theory and its sophisticated integrability. The obtained relations describe the form of the genus expansion for the HOMFLY polynomials, which for the corresponding matrix model is usually given using Virasoro-like constraints and the topological recursion. The genus expansion differs from the better-studied weak-coupling expansion at a finite number N of colors, which is described in terms of Vassiliev invariants and the Kontsevich integral. 相似文献
114.
O. Brovko A. Grebentsov N. Morozov E. Syresin M. Yurkov 《Physics of Particles and Nuclei Letters》2016,13(3):384-389
Diagnostic technique applied for FEL ultrashort electron bunches is developed at JINR-DESY collaboration within the framework of the FLASH and XFEL projects. Photon diagnostics are based on calorimetric measurements and detection of undulator radiation. The infrared undulator constructed at JINR and installed at FLASH is used for longitudinal bunch shape measurements and for two-color lasing provided by the FIR and VUV undulators. The pump probe experiments with VUV and FIR undulators provide the bunch profile measurements with resolution of several femtosecond. The new three microchannel plates (MCP) detectors operated in X-ray range are under development now in JINR for SASE1-SASE 3 European XFEL. 相似文献
115.
本文研究了算子代数的K-理论.利用代数拓扑方法,获得了复Hilbert空间上正常算子所生成算子代数的K-群与该算子谱几何性质的定性关系. 相似文献
116.
Gippius A. A. Zhurenko S. V. Büttgen N. Schädler M. Morozov I. V. Moskvin A. S. 《Physics of the Solid State》2019,61(5):723-727
Physics of the Solid State - An NMR analysis of 31P nuclei in metallic iron phosphide FeP has been performed both in a zero field and by sweeping the external magnetic field at several fixed... 相似文献
117.
118.
改进的Brenner图像清晰度评价算法 总被引:7,自引:2,他引:7
图像清晰度评价是基于数字图像的被动式自动调焦技术的基本问题之一.传统Brenner图像清晰度评价算法具有运算速度快特点,但是其评价准确性取决于阈值选取,且其灵敏度较低.针对上述问题,本文提出了一种改进算法.改进算法采用高通和带通两个滤波器对图像进行计算,克服阈值对传统Brenner算法评价结果的影响.为了衡量改进算法的性能,将其与传统的Brenner算法比较,并对评价算法的单峰性、无偏性、灵敏度、计算量等主要衡量标准逐一分析.实验结果表明:与传统的Brenner评价算法相比,改进算法在满足评价算法单峰性和无偏性前提下,提高了灵敏度,降低了计算次数. 相似文献
119.
研制了一台高分辨率极紫外光谱仪,用于磁约束等离子体诊断。采用一块具有平场特性的全息球面变线距光栅作为分光元件,光栅公称线密度为1 200 lines·mm-1,掠入射角为3°。一台可深度制冷、背照式面阵CCD作为光谱探测器,用机械快门控制曝光时间。通过CCD在光谱聚焦面的移动,可以记录的光谱范围为5~50 nm。用Penning放电光源测试了光谱仪的性能; 利用光源的标准谱线,进行了波长标定,波长精度为0.003 nm,并计算出系统各参数的实际值;当入缝宽度设置为30 μm时,在20 nm附近,光谱分辨率达0.015 nm,达到设计指标。 相似文献
120.
P. V. Morozov E. I. Grigor’ev S. A. Zav’yalov S. N. Chvalun 《Physics of the Solid State》2012,54(11):2291-2295
The hybrid poly-p-xylylene-cadmium sulfide nanocomposites characterized by gradients of concentrations and sizes of CdS nanoparticles along the lines of an applied electric field have been synthesized using the vapor deposition polymerization in an inhomogeneous electric field. The maximum concentration of cadmium sulfide can exceed 10 vol %, while the average effective sizes of the nanoparticles depend on the concentration and do not exceed 5 nm. The synthesized thin-film nanocomposites exhibit a quantum confinement effect. According to the estimates obtained from the shift of the absorption band edge, the radius of nanoparticles is 2.7 nm near the negative electrode and 3.5 nm near the positive electrode. It has been found that the sample formed in an electric field of 10 kV/cm manifests a rectification effect, which can be associated with the gradient of nanoparticle sizes. The measurements of current-voltage characteristics and photoconductivity have demonstrated that the synthesized samples possess high photoconductivity. The photocurrent in the sample prepared in an electric field of 10 kV/cm can exceed the dark current by two orders of magnitude, and the rectification effect in this case disappears. 相似文献