Phonon spectra in one-dimensional quasicrystals

The propagation of phonons in one-dimensional quasicrystals is investigated. We use the projection method which has been recently proposed to generate almost periodic tilings of the line. We define a natural Laplace operator on these structures, which models phonon (and also tight-binding electron) propagation. The selfsimilarity properties of the spectrum are discussed, as well as some characteristic features of the eigenstates, which are neither extended nor localized. The long-wavelength limit is examined in more detail; it is argued that one is the lower critical dimension for this type of models.     

氚核磁共振波谱在氚标记甾族化合物制备中的应用

本文介绍了十一种氚化甾族化合物的氚核磁共振谱。我们依照英国放化中心和英国萨里大学报道数据,(甾体骨架上的CH及CH_2各位置的谱线归属,应用了定位标记化合物作为对照)归属了其氚在化合物中标记的位置,根据其积分曲线定出了各位氚的相对百分含量。同时图谱中又提供了立体构型的信息,为氚化甾族化合物制备过程中,催化剂的选择,实验条件的控制及反应机理等研究提供了理论依据。     

Combined absorption of light in the process of photoactivation of biosystems

The light-oxygen effect consists in a direct excitation of molecular oxygen dissolved in aqueous media of biosystems by the light; it provides the possibility to use lasers for therapeutic purposes. The wavelength of the used light should strictly correspond to the oxygen absorption bands. However, laser therapy also makes use of lasers emitting at 0.89 μm (outside the known oxygen bands), which suggests the action of a new photoreceptor. Here we argue that this mechanism of photoreception is a modification of the light-oxygen effect involving the absorption of photon simultaneously by the oxygen molecule and O-H stretch of the H₂0 molecule of liquid water.     

Estimation of the proton energy spectrum in knee region by analog read-out of ARGO-YBJ experiment

Based on the six months data set of ARGO-YBJ experiment with analog read-out and its Monte Carlo simulation,we study the difference between different primaries induced showers by using the space-time information of the charged particles in Extensive Air Showers.With five parameters which can efficiently pick out primary proton induced showers as inputs of an artificial neural network,the proton spectrum from 100 TeV to 10 PeV can be obtained.     

Improving the dispersion and interfaces in polymer‐carbon nanotube nanocomposites by sample preparation choice

Polymer nanocomposites composed of poly(styrene‐ran‐vinyl phenol) (PSVPh) copolymers and 5 wt % multi‐walled carbon nanotubes (MWNTs) were prepared by three different methods, including melt‐mixing and precipitation. The MWNTs were either oxidized to incorporate oxygenated defects or utilized as received. The mechanical properties of the nanocomposites were measured by dynamic mechanical analysis (DMA), and the extent of intermolecular hydrogen bonding between MWNTs and PSVPh was quantified by infrared (IR). Our DMA results suggest that melt‐mixing leads to more stable morphologies of the final nanocomposites than precipitation. Additionally, the IR analysis of the nanocomposites indicates melt‐mixing can result in the formation of more intermolecular hydrogen bonding between the MWNTs and PSVPh than precipitation, and thus suggests that melt‐mixing leads to more reproducible mechanical properties than precipitation. Our DMA and IR results may provide guidelines to realize the desired morphologies and to improve the properties of polymer carbon nanotube nanocomposites by optimizing intermolecular interactions between MWNTs and polymers using processing. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1747–1759, 2008     

Interpretation of IR spectra of the N-acethyl-4-dimethylaminopyridinium salts

In a harmonic approximation we calculate the frequencies of normal vibrations and their modes for a salt cation of N-acethyl-4-dimethylaminopyridinium hexachlorstibiate and of its three deuteroderivatives obtained on deuteration over a CH₃-group, over a ring, and over a ring and a CH₃-group. From the results of calculation, an interpretation of the IR spectra of the salts considered is carried out. To whom correspondences should be addressed. L. M. Litvinenko Institute of Physical and Organic Chemistry and the Chemistry of Coal, National Academy of Sciences of Ukraine, 70, R. Luxemburg Str., Donetsk, 340114, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 2, pp. 158–162, March–April, 1999.     

Wet sol–gel silica matrices as delivery devices for phenytoin

Wet sol–gel silica matrices produced under different hydrolysis conditions were used as delivery devices to the active principle of an antiepileptic drug (phenytoin sodium), encapsulated during the condensation stage. Post-incorporation into dry silica powder was an alternative loading procedure. It was proven by infrared spectroscopy that neither the silica network nor the drug loose integrity by encapsulation. The kinetics of in vitro drug release was studied at 37 °C, to water and to artificial cerebrospinal fluid (ACSF). Emphasis has been given to the release to ACSF under dynamic conditions (with fluid renovation, emulating what occurs in the brain). Different delivery regimes were identified and correlated with the loading method and the matrix structure. Matrices with lower total porosity and smaller average pore size proved to be better for a long term release. Renovation of ACSF is relevant to assure a constant concentration of phenytoin in the vicinity of the device.     

餐盒用新型非发泡聚丙烯光降解性能红外光谱法检测

用红外光谱法测试研究了餐盒用新型非发泡聚丙烯光降解行为。结果表明，降解母粒含量不同，其红外吸收光谱图存在明显的差异；在光降解过程中，羰基指数存在明显的动态变化。     

A Uniform Exponential Spectrum for Linear Flows on Vector Bundles

For linear flows on vector bundles we define a uniform exponential spectrum. For a compact invariant set for the projected flow we obtain this spectrum by taking all accumulation points for the time tending to infinity of the union over the finite time exponential growth rates for all initial values in this set. Using direct arguments we show that for a connected compact invariant set this spectrum is a closed interval whose boundary points are Lyapunov exponents. For a compact invariant set on which the flow is chain transitive we show that this spectrum coincides with the Morse spectrum. In particular, this approach admits a straightforward analytic proof for the regularity and continuity properties of the Morse spectrum without using cohomology or ergodicity results.