Ellipsometric and Raman Spectroscopic Study of Thermally Formed Films on Titanium

Thermal films on titanium surfaces were formed by heating titanium samples in air at atmospheric pressure. The optical constants, thickness, and structure of the formed films at various temperatures and times of heating were investigated by ellipsometry and Raman spectroscopy. The complex index of refraction and the thickness of generated films were determined by comparing the experimental loci and obtained by ellipsometric measurements with theoretical computed vs. curves. It was found that the thickness in homogeneity and porosity of formed films increase with increasing temperature and the duration of the thermal treatment. Beyond a certain critical temperature, the appearance of some Raman bands and changes in their intensities indicated that the film transformed from amorphous to microcrystalline and crystalline structure

Anodic Behavior of Ti in KOH Solutions: Ellipsometric and Micro-Raman Spectroscopy Studies

Anodic formation of oxide films on titanium surfaces, in various concentrations of aqueous KOH solutions, have been studied using ellipsometry and micro-Raman spectroscopy. By in situ ellipsometric measurements the coefficient of film thickness growth and indexes of refraction of anodic oxide films have been determined. The voltage at which the oxide film breaks down is strongly dependent on the KOH concentration. Further, the solution concentration strongly influences the potential at which the oxide film is transformed from the amorphous state to crystalline form. Using micro-Raman spectroscopy four crystalline forms of titanium oxides, namely, anatase, brookite, corundum, and rutile, have been identified. The crystalline form of the surface oxide is shown to depend on the applied voltage and on the time of anodization. The micro-Raman spectra reveal that brookite and corundum are intermediate forms of the anodic oxide films and the final film formed is primarly composed of an anatase type of TiO2

Применение уравнений Френеля в статистическом анализе эллипсометрических данных - определение оптических показателей анодно полученных плёнок из TiO2

Оптические показатели TI02 плёнок , определены эллилсометрически при стандартных ех-ситовых условиях в видимой спектральной области. Плёнки , изготовленные из Ti02, получены анодным окислением электрополирован:ной титановой поверхности в области потенциала от О до 100 V. Путём вычисления:, с помощью измеренных эллипсометрических параметров L1 и Р и Френеловых уравнений, показано , что численное значение оптических показателей уменьшае11ся: с изменением т олщины плёнки, и что у тол·стых плёнок они получают постоянные значения:. Исползован и ем различных спос обо в выч исления: пок.азано, каким образом можно получить наиболее точные рез у ль таты, т. е. самая: маленькая: погрешность при статистической обработке эллипсометрических д анных

Применение уравнений Френеля в статистическом анализе эллипсометрических данных - определение оптических показателей анодно полученных плёнок из TiO2

Оптические показатели TI02 плёнок , определены эллилсометрически при стандартных ех-ситовых условиях в видимой спектральной области. Плёнки , изготовленные из Ti02, получены анодным окислением электрополирован:ной титановой поверхности в области потенциала от О до 100 V. Путём вычисления:, с помощью измеренных эллипсометрических параметров L1 и Р и Френеловых уравнений, показано , что численное значение оптических показателей уменьшае11ся: с изменением т олщины плёнки, и что у тол·стых плёнок они получают постоянные значения:. Исползован и ем различных спос обо в выч исления: пок.азано, каким образом можно получить наиболее точные рез у ль таты, т. е. самая: маленькая: погрешность при статистической обработке эллипсометрических д анных

An Essential Role for Katanin p80 and Microtubule Severing in Male Gamete Production

Katanin is an evolutionarily conserved microtubule-severing complex implicated in multiple aspects of microtubule dynamics. Katanin consists of a p60 severing enzyme and a p80 regulatory subunit. The p80 subunit is thought to regulate complex targeting and severing activity, but its precise role remains elusive. In lower-order species, the katanin complex has been shown to modulate mitotic and female meiotic spindle dynamics and flagella development. The in vivo function of katanin p80 in mammals is unknown. Here we show that katanin p80 is essential for male fertility. Specifically, through an analysis of a mouse loss-of-function allele (the Taily line), we demonstrate that katanin p80, most likely in association with p60, has an essential role in male meiotic spindle assembly and dissolution and the removal of midbody microtubules and, thus, cytokinesis. Katanin p80 also controls the formation, function, and dissolution of a microtubule structure intimately involved in defining sperm head shaping and sperm tail formation, the manchette, and plays a role in the formation of axoneme microtubules. Perturbed katanin p80 function, as evidenced in the Taily mouse, results in male sterility characterized by decreased sperm production, sperm with abnormal head shape, and a virtual absence of progressive motility. Collectively these data demonstrate that katanin p80 serves an essential and evolutionarily conserved role in several aspects of male germ cell development

Ellipsometric in situin~situ study of the titanium surfaces during the anodization

The titanium surfaces immersed in 0.5 mol.dm$^{-3}$ H$_{2}$SO$_{4}$ and anodized in the voltage region from 0 to 100 V have been studied by in situ ellipsometric measurements. The thickness, inhomogeneity, and porosity of the formed films rise with increasing applied voltage. A computational method is presented for obtaining both the refractive indices and thickness of an unknown film on a reflecting substrate of know optical constants. The complex index of refraction and thickness of generated films were calculated comparing the theoretical computed curve with experimental loci $\Delta$ and $\Psi$ obtained from in situ ellipsometric measurements

Studies on Activated Carbon Capacitor Materials Loaded with Different Amounts of Ruthenium Oxide

Ruthenium oxide–carbon composites with different loadings of RuO2 on carbon have been synthesized by an electroless deposition process. Increase in RuO2 loading results in increasing the specific capacitance of the composite electrode. The effect of temperature treatment on the performance of these materials has been studied in detail. Maximum capacitance was observed after heat treatment at 100°C for all the composites. Increasing the oxidation temperature further converts the Ru oxides to crystalline form, which leads to poor capacitance values. A maximum capacitance of 260 F/g was obtained for 20 wt.% RuO2loaded carbon treated at 100°C. The volumetric surface area of the composite remains constant with increased RuO2 loading. Since Ru oxides have a large pseudocapacitance, this increases the volumetric capacitance of the carbon significantly

An ESR, Mass Spectrometry and Fluorescence microscopy approach to study the stearic acid derivatives anchoring in cells

peer reviewedLateral phase separations in biological membranes are of great interest, making Electron Spin Resonance (ESR) spectroscopy combined with spin labelling a non destructive and sensitive technique for the study of lipid rafts. This is currently accepted that spin probe localization is on the plasma membrane. However, no study confirms this hypothesis. Herein, we report, for the first time, an accurate multi spectral method for the quantification of lipid spin label presence in every sub-cellular fraction. Cells were incubated with 5-doxyl stearic acid derivative and then sub-fractionated. Results of our multimodal spectroscopy approach ubiquitously demonstrate that the presence of ESR spin label only sets in the plasma membranes