Miracle-dz/UniFAR-FTUs huggingface dataset:
Second‐Order Doppler Shift of Fe57 Mössbauer Resonance in Al‐0.01% Fe57 Alloy Solid Solution

The Mossbauer effect of Fe57 in aluminum was measured over a temperature range from 4.2 °K to 453 °K, using a specimen of supersaturated solid solution of Al-0.01% Fe57 alloy. From the temperature dependence of the Mossbauer peak position, the second-order Doppler shift and the isomeric shift of Fe57 in aluminum were estimated separately from the observed total shifts assuming the isomeric shift to be temperature independent. The estimated temperature independent isomeric shift was (0.52 ± 0.02) mm/s relative to metallic iron, somewhat different from the usual room temperature value of (0.43 ± 0.02) mm/s. The temperature dependent second-order Doppler shift was analysed by the recent Mannheim's expression and the Debye formula. The best fitted force-constant ratio, λ′/λ, for the iron atom in aluminum host lattice was estimated to be 0.5 < λ′/λ < 1. The zero point kinetic energy of Fe57 in Al was also evaluated by differences between the shifts at 4.2 °K and those at high temperatures. Der Mosbauer-Effekt von Fe57 in Aluminium wurde an einer ubersattigten Aluminium-Legierung mit 0,01 At. -% Fe57 im Temperaturbereich von 4,2 bis 453 °K untersucht. Durch die Messungen der Temperaturabhangigkeit der Lage der Mossbauer-Spektren wurden die Doppler-Verschiebung zweiter Ordnung und die isomere Verschiebung von Fe57 in Aluminium aus der gesamten Verschiebung, unter der Annahme, das and die isomere Verschiebung unabhangig von der Temperatur ist, getrennt bestimmt. Die so bestimmte, von der Temperatur unabhangige isomere Verschiebung betrug (0,52 ± 0,02) mm/s relativ zu metallischem Eisen. Dieser Wert ist etwas von dem ublichen Wert bei Raumtemperatur, (0,43 ± 0,02) mm/s, verschieden. Die von der Temperatur abhangige Doppler-Verschiebung zweiter Ordnung wurde mit dem neuen Mannheimschen Ausdruck und der Debyeschen Gleichung analysiert. Das am besten angepaste Verhaltnis der Kraftkonstanten, λ′/λ, fur das Eisenatom in dem Gitter des Aluminiums wurde zu 0,5 < λ′/λ < 1 abgeschatzt. Die kinetische Nullpunktsenergie von Fe57 in Al wurde durch die Differenz zwischen den beiden Verschiebungen bei 4,2 °K und hohen Temperaturen abgeschatzt.
Study on Photocatalytic Degradation of X-3B by TiO2 Nanotube Arrays

In the present work, highly ordered TiO2 nanotube array with diameter were fabricated by one-step or two-step anodization of titanium foils. The prepared arrays were characterized by field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activity of the TiO2 nanotube arrays was determined by degradation of X-3B under UV and compared to direct photolysis. The results showed that its photocatalytic activity in degradation of X-3B had been dramatically enhanced as compared to direct photolysis, and the photocatalytic performance of TiO2 nanotube arrays prepared by one-step anodization was better than that made by two-step anodization. Furthermore, adsorption performance analysis suggested that the higher catalytic activity of one-step nanotube array was attributed to its larger apparent maximum number.
Cryotrapping assisted mass spectrometry for the analysis of complex gas mixtures

A simple method is described for the unambiguous identification of the individual components in a gas mixture showing strong overlapping of their mass spectrometric cracking patterns. The method, herein referred to as cryotrapping assisted mass spectrometry, takes advantage of the different vapor pressure values of the individual components at low temperature (78K for liquid nitrogen traps), and thus of the different depletion efficiencies and outgassing patterns during the fast cooling and slow warming up of the trap, respectively. Examples of the use of this technique for gas mixtures with application to plasma enhanced chemical vapor deposition of carbon and carbon-nitrogen hard films are shown. Detection of traces of specific C3 hydrocarbons (<50ppm of initial methane) in methane/hydrogen plasmas and the possible trapping of thermally unstable C–N compounds in N2 containing deposition plasmas are addressed as representative examples of specific applications of the technique.
Performance Evaluation of Light Emission Models in Light Attenuating Media

The light distribution models developed in the literature have been mostly tested by conducting experiments in an annular reactor full of either air or deionized water, where the attenuating coefficients of the media were assumed to be zero. Although many of these models have predictive capability of the effect of absorbing media according to the Beer–Lambert law, their real performance in light attenuating media has seldom been investigated. In this study, the predicted local light intensities by three emission models in an attenuating medium were compared with experimental data. Potassium ferrioxalate actinometry was used to measure the light intensity profile within the reactor, and ozone at various concentrations was used as an attenuating medium, since it has a large molar absorption coefficient in the ultraviolet region of the electromagnetic spectrum. In addition, ozone is used as an external oxidant in many photochemical reactions. It was found that the predicted values using all three models were significantly lower than the experimental data, especially at high concentrations of ozone, while the performance of the emission models improved markedly at low concentrations of ozone. The discrepancy between the experimental data and the predicted values may be due to two reasons: (1) the Beer–Lambert law was developed for parallel light fields, and (2) violation of the prerequisite of the Beer–Lambert law (i.e., applicability of the law only at low concentrations). Although not discussed fully in the original Beer–Lambert law, it is frequently observed that the law is not obeyed when the light path length is relatively long and when light-absorbing species are present in the quartz cell of a spectrophotometer. The same phenomenon occurred in the test annular reactor, where the performance of the emission models worsened with the distance away from the light source. Thus, the application of light models in media with non-negligible light attenuating coefficients should be carefully reconsidered.
Constructive-synthesizing model of text graph representation

The article describes the graph model of the text, allowing speeds up processing. This model allows us to identify the same fragments in the documents with the change in the order of sentences and other parts. Using constructive-synthesizing structure to formalize this model is a promising approach to further automate the process of working with the model and the text accordingly. Problems in programming 2016; 2-3: 63-72
Volumetric and Viscometric Studies of Molecular Interactions of Binary Liquid Mixtures of Styrene with Acetone and Dimethylsulphoxide at Different Temperatures

The present work reports the results of densities, ρ, viscosities, η, ultrasonic speeds, u, and refractive indices, n, of pure styrene (STY), acetone (ACT) and dimethylsulphoxide (DMSO) and of their binary liquid mixtures over the entire composition range at 298.15, 303.15, 308.15, and 313.15 K. The excess molar volumes, V E , excess intermolecular free lengths, , deviations in isentropic compressibilities, Δk s , viscosities, Δη, and in refractive indices, Δn were calculated from the experimental data. Partial molar volumes, , and partial molar compressibilities, , of ACT and DMSO in styrene at infinite dilution and at different temperatures have been evaluated. Apart from using density data for the calculation of V E , excess molar volumes have also been estimated by using the Flory's statistical theory and refractive index measurements.
Uranyl binding to humic acid under conditions relevant to cementitious geological disposal of radioactive wastes

Abstract Few studies have sought to investigate the potential for dissolved organic matter (DOM) to bind (and thus potentially transport) radionuclides under the high pH regimes that are expected in cementitious disposal. We have used equilibrium dialysis to investigate uranyl binding to humic acid over a pH range of ~10 to 13. The experimental results provide evidence that DOM can bind uranyl ions over this pH range, including in the presence of competing ions. There is a general decrease in binding with increasing pH, from ~80% of total uranyl bound at pH 9.8 to ~10% at pH 12.9. Modelling of the system with WHAM/Model VII can yield representative results up to pH ~10.5.
Alle Jahre wieder: die Chemie der Weihnachtskerze

Wenn wir am Heiligen Abend die Kerzen entzunden, treiben wir ein Stuck besonders schoner, aber auch besonders komplexer Chemie. Von der im Inneren der strahlenden Kerzenflamme ablaufenden Chemie haben wir nur ungefahre Vorstellungen, viele Details sind uns noch verborgen. Klar ist jedoch, dass letztlich gluhende Ruspartikel unseren Wohnstuben den festlichen Glanz verleihen. Im Weltraum sahe es ganz anders aus: die molekularen Exoten C2* und CH* wurden mit ihrem kaum sichtbaren, blassblauen Licht unsere Augen wohl kaum zum Leuchten bringen. Ist es nicht wunderbar, dass die Chemie der Kerze fur unsere irdischen Wohnzimmer optimiert ist? In diesem Sinne: Frohliche Weihnachten!
Bis(phthalocyaninato)erbium (α1 Phase)

In the title compound, α1-bis(phthalocyaninato)erbium {(α1-[Er(Pc) 2 ], where Pc = C 32 H 16 N 8 2-/- }, Er III is eightfold coordinated by the isoindole N atoms (N iso ) of the two staggered (41.4°) saucer-shaped Pc ligands. The Er-N iso distance is 2.41(1)A ; the height of the slightly distorted ErN 8 square antiprism is 2.74A. The [Er(Pc) 2 ] molecules are packed in columns parallel to the tetragonal c axis. In this new tetragonal α1 phase, the disposition of the metal ion is ordered and the Pc rings are structurally equivalent.
Measurements of temperature fluctuations in a large-scale turbulent high-pressure flame using CARS

A mobile CARS system has been used to determine temperatures and their fluctuations in a high pressure combustion test rig with a maximum thermal power of 8 MW. Measurements have been performed in turbulent natural gas and oil flames up to a pressure of 14 bar. A high degree of turbulence and an increased pressure together with an extended size of the combustion chamber caused beam propagation effects to become a serious problem for this measuring technique. Temperature determinations in sooty oil flames became even more difficult due to the strong absorption of a part of the fundamental band of the N2 CARS spectrum by C2 radicals. Probability density functions of the temperature, each based on 1000 single shot measurements, have been determined at different radial and axial locations within the combustion chamber.
A versatile, one-pot synthesis of gold nanostars with long, well-defined thorns using a lyotropic liquid crystal template

We describe a simple, one-pot, silver-assisted synthesis of branched gold nanoparticles (GNPs) (nanostars) using Ag NO3 and the mild reducing agent, ascorbic acid, in the presence of a lyotropic liquid crystal (LLC) template formed by Triton X-100 in water either in the hexagonal phase or the micellar phase above the critical micellar concentration. The LLC template is found to assist in the formation of well-defined nanostars with long, twinned thorns and provides the necessary colloidal stability that prevents the final nanostars from irreversible aggregation. In addition, the length of the thorns on the nanostars can be tailored by controlling the Au/Ag ratio in the growth solution. We discuss the contributions of the competing mechanisms that result in an optimal concentration of AgNO3 for the synthesis of nanostars with considerably longer thorns, which is only possible in the LLC template that slows down the growth of the thorns on the initially formed GNP seeds.
EUV studies of N2 and O2 produced by low energy electron impact

The emission spectrum of atomic nitrogen (NI), singly ionized atomic nitrogen (NII), atomic oxygen (OI), singly ionized atomic oxygen (OII), and molecular nitrogen (N2) dominates the day airglow and aurora spectrum in the extreme ultraviolet. However, analysis of the excitation of these lines is not possible due to the lack of laboratory or theoretical data for the relevant processes. Absolute emission excitation cross sections resulting from low energy electron impact on N2 and O2 have been measured in the extreme vacuum ultraviolet (500–1200 A). Electron energies were from 0 to 300 eV. Numerous bands of N2 were found between 800 and 1000 A. These band systems are of particular interest because their optical oscillator strengths are unusually large and should have large emission cross sections. Excitation functions were measured for the N2 c′ 1Σ+u → X 1Σ+g v′=0−v″=0 band emission, the NII 916 A multiplet, the OI 879 A multiplet, and the OII 834 A multiplet. In addition, cross sections were measured at 20.
On the crystallographic and magnetic structures of nearly stoichiometric iron monoxide

Abstract Neutron diffraction experiments have been carried out at room temperature and at 12 K on a polycrystalline three-phase sample of nearly stoichiometric wustite, magnetite, and iron (mole fractions 0.914, 0.080, and 0.006) in order to extend the structural description of wustite to a region were defect clusters should be of less importance. The sample was prepared by controlled disproportionation of a quenched wustite with composition Fe 0.9347 O. Tetrahedral iron interstitials could not be substantiated from refinement of the room temperature diffraction pattern, hence showing that the number of defect clusters is small. The character of the magnetic order–disorder transition is significantly changed upon going from the highly nonstoichiometric regime to nearly stoichiometric FeO. The transition in near stoichiometric FeO is strongly cooperative. Two components of the low temperature antiferromangetic structure is extracted, the main component (μ ∥ = 3.8(4) μ B ) is along the unique axis [111], while a second smaller (μ ⊥ = 1.3(3) μ B ) is perpendicular to the unique axis.
Linear and nonlinear optical absorption coefficients and refractive index changes in spherical quantum dots : Effects of impurities, electric field, size, and optical intensity

In the present work, the case of a spherical quantum dot with parabolic confinement subjected to an external electric field with the presence of an impurity, the linear and third-order nonlinear optical absorption coefficients as well as refractive index changes have been calculated. The numerical method we are using for the calculation of the energy levels and the corresponding wave functions is the potential morphing method in the effective mass approximation. As our results indicate an increase of the electric field and/or the position of the impurity and/or the quantum dot radius redshifts the peak positions of the total absorption coefficient and total refractive index changes. Additionally, an increase of the position of the impurity and/or the quantum dot radius decreases the total absorption coefficient and increases the total refractive index changes. An increase also of the electric field decreases the total absorption coefficient but does not significantly affect the peak values of the total refractive index changes. Finally, an increase of the optical intensity considerably changes the total absorption coefficient as well as the total refractive index changes.
An experimental study of plasma density determination by a cylindrical Langmuir probe at different pressures and magnetic fields in a cylindrical magnetron discharge in heavy rare gases

This article presents an experimental study that contributes to the problem of interpretation of cylindrical Langmuir probe data obtained in a non-isothermal low-temperature plasma in magnetic field. A discussion on the influence of positive ion - neutral collisions on the charged particle density estimation is also given and the effect is demonstrated on the experimental data. A Maxwellian electron energy distribution is assumed throughout the present study. The Langmuir probe data are obtained in a cylindrical magnetron discharge in argon at pressures from 1.5 to 6 Pa and magnetic fields between 100 and 500 G. The radially movable Langmuir probe was made of either m or m diameter tungsten wire in order to investigate the effect of the probe dimensions on the estimated plasma density. The electron density is calculated from the electron current at the space potential (used as a reference) and from the OML collisionless theory. The ion density is calculated by using ABR - Chen theory without and with the correction due to the collisions of positive ions in the probe sheath. Also, the recent collisional positive-ion-collection-theory is used for comparison. The resulting numerical values of plasma density are compared over more than one order of magnitude change in the plasma density given by its radial dependence in the cylindrical magnetron discharge. Optical measurements were made in order to quantitatively assess the neutral gas temperature in the discharge and the density of particles in excited states that could induce secondary electron emission from the probe surface and thus apparently enhance the positive-ion density estimated from the probe positive-ion current. The effect of secondary electron emission from the probe surface on the probe data interpretation has been found small compared to the experimental error limits and consequently not substantial for our experimental conditions. In the range of our experimental conditions the ABR - Chen theory with the collisional correction gives the best agreement of the estimated numerical values of ion and electron densities in the whole range of its investigated change. Also from our results it follows that the effect of the magnetic field on the thinner-probe-electron-current at the space potential and hence on the reference-electron-density-estimation is negligible within the experimental uncertainties up to a magnetic field strength of 500 G which was the maximum used in our experimental study.
Ordered Phase of Platelike Particles in Concentrated Dispersions

The coexistence of two phases in concentrated dispersions of monodispersed platelike particles is reported. Small-angle neutron diffraction has been used to identify a highly ordered phase which coexists at equilibrium with a less ordered, less dense phase. The interparticle interactions were varied by adjusting the salt concentration, and this influenced the concentration at which the phase transition occurred. Columnar or layer structures which could account for the observed diffraction pattern from the ordered phase are discussed.
Research of Three-Layer Cellular Neural Networks Processing Color Images

Abstract In this study, we propose the three-layer cellular neural network considering three primary colors. In our propose three-layer cellular neural network, the connections between the three layers play an important role. Namely, the three layers do not operate independently but all the outputs influence to the other layers. Also, before the processing in the propose method, a color image is divided into three primary colors and they are converted to three gray-scale images corresponding to red value, green value, and blue value. In this research, we show some edge enhancement more effectively than the original cellular neural networks by computer simulation.
Influence of stoichiometry on the glass transition and bond exchange reactions in epoxy thermoset polymers

Thermally malleable polymers which undergo covalent bond exchange reactions (BERs) have been shown to be able to rearrange their network topology at high temperatures without impairing the network integrity. At low temperatures, the BERs are so sluggish that the materials behave like traditional thermosetting polymers. In this paper, we demonstrated that the temperature dependent BER rate could be tuned by adjusting the stoichiometry of monomers. As the ratio of hard segments in the epoxy thermoset network is increased, the material's glass transition temperature (Tg) is increased, with a corresponding increase in the temperature required to achieve a given stress relaxation rate. The material stress relaxation behavior was studied from both a theoretical and experimental point of view. Based on the kinetics of BERs, we derived the detailed expression of stress relaxation time, which reveals an Arrhenius type dependency of material relaxation behavior on the applied temperature. Subsequently, from the experimental stress relaxation curves, we determined the energy barrier for the BERs in different networks. With the Tg being elevated from 30.3 °C to 63.0 °C, the BER energy barrier is linearly increased from 68.2 kJ mol−1 to 97.3 kJ mol−1. Such a correlation between these two thermomechanical behaviors provides an additional design parameter (beyond catalyst choice) which can aid in achieving highly tunable service conditions for practical engineering applications of thermally malleable thermosets.
Antibacterial Activity of TiO2 and Fe3+ Doped TiO2 Nanoparticles Synthesized at Low Temperature

Nanocrystalline TiO2 powder with and without Fe3+ doping were successfully synthesized at low temperature by a microwave-assisted sol–gel method. The synthesized TiO2 powders were characterized by XRD, BET, FT-IR and SEM. It was found that anatase phase was formed after refluxed at 80°C using a domestic microwave oven. Antibacterial behavior towards E. coli was then studied under UV and fluorescent irradiation. The synthesized pure TiO2 powder exhibited superior antibacterial activity under fluorescent irradiation compared to the commercial TiO2 (Degussa P25). It can efficiently destroy E. coli bacteria after 20 min with UV irradiation and 3 h with fluorescent light; this good activity is mainly related to the high OH radicals on its surface. It was also observed that the synthesized powders have smaller crystallite size and larger specific surface area than those of Degussa P25 due to the absence of high temperature calcination requirement.
A New Water Sorption Equilibrium Expression for Solid Foods based on Thermodynamic Considerations

Solution thermodynamics was used to derive a new semitheoretical expression to represent sorptional equilibrium in food products having both temperature and water content as independent variables. A number of correlations have been studied and compared with the proposed equation using different requirements, necessary for their application in mathematical modeling and engineering calculations. These criteria were their capabilities to fit the experimental data, to evaluate the derivatives and the heat of sorption, and to predict the behavior at high moistures. On this basis, it was concluded that the present expression provided an accurate description of the sorptional behavior for many food systems.