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The optical and electrochromic properties of thin films obtained by centrifugation from solutions containing ambipolar polyimides with pendant groups based on 9H-thioxanthene-9-one and its S-dioxide derivative are studied using spectral ellipsometry, spectrophotometry, and spectroelectrochemistry. It is shown that the spectral dependences of the refractive index n(E) and the absorption coefficient α(E) as well as the electrochromic properties of polyimide thin films under electrochemical reduction and oxidation conditions strongly depend on the type of the pendant group. Based on the estimates of the band gap Eg a conclusion is made about the possible promising use of thin films of polyimides as working layers in memristors of a new type. Keywords: memristors, dielectric films, ambipolar polyimides, ellipsometry, electrochromism.

The microstructures of amorphous and polycrystalline ferroelectric Hf0.5Zr0.5O2 films are studied by X-ray spectroscopy and ellipsometry. EXAFS spectra demonstrate that the amorphous film consists of an “incompletely mixed” solid solution of metallic oxides HfO2 and ZrO2. After rapid thermal annealing, the mixed Hf0.5Zr0.5O2 oxide films have a more ordered polycrystalline structure, and individual Hf and Zr monoxide islands form in the films. These islands are several nanometers in size and have a structure that is similar to the monoclinic structure of HfO2 and ZrO2. The presence of the HfO2 and ZrO2 phases in the Hf0.5Zr0.5O2 films is also detected by ellipsometry

X-ray photoelectron spectroscopy, EXAFS, XANES, spectral ellipsometry and quantum-chemistry calculations were used to examine the atomic and electronic structure of non-stoichiometric amorphous ZrOx slightly enriched with zirconium. The experimental data show that the ZrOx material consists of stoichiometric ZrO2, metallic Zr and zirconium suboxides ZrOy. The structure of ZrOx is analyzed using the Random Bonding and Random Mixture models. A model of nanoscale spatial potential fluctuations in ZrOx is substantiated. In this model, the potential fluctuations for electrons and holes arise due to the local fluctuations of bandgap energy in the range from 0 to 5.4 eV. A ZrOx-based flash memory element with giant retention time is proposed

BackgroundThe aim of this work was to assess the potential of the optical methods for studying erythrocytes (Er) and blood serum (BS) of patients with colorectal cancer (CC).MethodsA total of 26 persons (52+8years old) with CC (histologically – adenocarcinoma) in the T1–2 stage (the 1st group consisting of 10 patients) and in the terminal stage T3–4 (the 2nd group involving 16 patients) were examined. The metastases (in the liver area) were detected in 6 patients; the remaining patients had no metastases. The degree of lymph node involvement in most patients was not determined, the ten corresponding N1. The control group consisted of 16 healthy people (50+6years old). Electric and viscoelastic Er parameters were investigated by dielectrophoresis, their membrane structure – by TLC and gas chromatography. The optical properties of BS were studied by the methods of ellipsometry. The reaction of the monoclonal antibody CD 24 with BS antigens of CC patients was studied by spectroscopic ellipsometry close to the conditions of surface plasmon resonance (SPR) (ProteOn XPR36 (BioRad).ResultsWe observed significant differences in Er parameters, associated with the CC stage. Given in the 2nd group (T3–4) summarized rigidity, viscosity, electrical conductivity, the relative polarizability, indexes of aggregation and destruction were significantly higher than those in the 1st (T1–2) and in the control group (p