Miracle-dz/UniFAR-FTUs huggingface dataset:
Internal Friction Studies on Oxygen-Oxygen Interaction in Niobium. I. Experimental Results and Application of Previous Interpretations

In order to further clarify the long-lasting controversy on the origin of the broadening of the Snoek maxima of heavy solute interstitial atoms (C. N. O.) in the internal friction of b.c.c. metals due to an interaction between those atoms measurements were carried out on niobium with various oxygen contents (0.1 to 0.85 at%) by applying frequencies of about 1 Hz and about 1 kHz to identical specimens. The means activation enthalpy of relaxation as determined from the frequency shift of the peak temperatures turns out to be independent of the oxygen content, Hm = (1.15 ± 0.01) eV. The maxima are rather symmetrically broadened and shifted to higher temperature with increasing oxygen content. They are analysed in terms of previously introduced models. The clustering model proposing a superposition of discrete Debye submaxima for O pairs, triplets, etc. does not give an adequate description of the total Snock maxima. Consequently, their broadening may only be accounted for by a continuous distribution of relaxation times. Attempts with empirical approaches, like Gaussian or Fuoss-Kirkwood distributions, yield a better but still insufficient agreement with the measurements. This indicates that an appropriate physical model for the interaction of interstitial solute atoms in b.c.c. metals is required to match the experimental data with their precision reached now. Zur weiteren Klarung der lang andauernden Kontroverse uber die Ursache der Verbreiterung der Snock-Maxima der inneren Reibung schwerer interstitiell geloster Atome (C, N, O) in k.r. z. Metallen infolge einer Wechselwirkung zwischen diesen Atomen wurden an Niob mit unterschiedlichem Sauerstoffgehalt (0,1 bis 0,85 At%) Messungen unter Anwendung von Frequenzen von etwa 1 Hz und etwa 1 kHz an ein und denselben Proben durchgefuhrt. Die mittlere Aktivierungsenthalpie der Relaxation, bestimmt aus der Frequenzverschiebung der Maximumstemperatur, ergibt sich als unabhangig vom Sauerstoffgehalt zu Hm = (1,15 ± 0,01) eV. Die Maxima werden mit zunehmendem Sauerstoffgehalt ziemlich symmetrisch verbreitert und zu hoherer Temperatur verschoben. Sie werden auf der Grundlage fruher eingefuhrter Modelle analysiert. Das Cluster-Modell, in dem eine Uberlagerung diskreter Debye-Untermaxima fur Sauerstoff-Paare, -Triplets usw. vorgeschlagen wird, ergibt keine adaquate Beschreibung der Gesamtmaxima. Folglich durfte deren Verbreiterung nur durch eine kontinuierliche Verteilung von Relaxationszeiten zu erfassen sein. Versuche mit empirischen Ansatzen, wie Gauss- oder Fuoss-Kirkwood-Verteilungen, ergeben eine bessere, aber immer noch unvollstandige Ubereinstimmung mit den Mesergebnissen. Dies zeigt, das ein geeignetes physikalisches Modell fur die Wechselwirkung unter interstitiellen Losungsatomen benotigt wird, um den experimentellen Daten mit ihrer jetzt erreichten Genauigkeit gerecht zu werden.
The normal modes of a protein: Native bovine pancreatic trypsin inhibitor

A completely general treatment of normal mode analysis is developed that can be used with any potential energy function and any set of generalized coordinates. The method is applied to the calculation of the normal modes of the small protein bovine pancreatic trypsin inhibitor that has been the subject of many previous theoretical studies. The potential energy function used comprises a torsion angle potential, a van der Waals potential between nonbonded pairs of atoms, and a hydrogen bond potential. Therefore, the generalized coordinates used are the 208 Φ, ϕ, and χ torsion angles about single bonds. This eliminates the difficulties inherent in using internal or Cartesian coordinates for a large molecule. Many dynamic properties of the protein may now be calculated in the normal mode description. In particular, the rms magnitudes and pair correlations of the fluctuations in positions and velocities of the α-carbon atoms and various classes of torsion angles, such as backbone, side chain, β-sheet, and α-helix, are calculated and analyzed to identify the most correlated modes. In addition, the ir intensities are calculated.
Homodyne light beating spectroscopy of o‐terphenyl in the supercooled liquid state

The laser light scattering intensity fluctuations of supercooled liquid o‐terphenyl at temperatures between 12 and −15 °C have been studied using the photon‐correlation technique. The time correlation functions obtained using the VV and VH scattering configurations at 90° scattering angle show a wide distribution of relaxation times. Angular‐dependent measurements at 45°, 90° and 135° scattering angles show that the time correlation functions for VH and for VV are independent of scattering angles. The VV and VH correlation functions cannot be fit to a bimodal distribution function; neither can they be fit to a cumulant expansion expression with less than four cumulants, but they can be satisfactorily fit to the William–Watts distribution function. The mean relaxation times derived for both isotropic and anisotropic scattering processes from the VV and VH correlation functions are nearly equal. The temperature dependence of the relaxation times cannot be described by an Arrhenius equation with a constant a.
Mathematics, Multicultural Education, and Professional Development.

Multicultural education grew out of the civil rights movement and, as such, is grounded in a vision of democracy, social justice, pluralism, and equality-ideals that have yet to be realized in U.S. society and its schools. For the past 25 years, multicultural education has served as a mobilizing focus for struggles to articulate visions of schooling that are consistent with the ideals of the U.S. and for the development of theory and research that offer a countervision to the way that schooling is usually conducted, particularly for children from historically marginalized groups. As this body of theory and research has grown so also have the implications for restructuring various dimensions of the education enterprise. Mathematics is one such dimension and is the focus of this article. First, however, I contextualize the discussion that follows within a vision of what multicultural education means. Multicultural education advocates teaching in a way that cultivates the intellectual capabilities of children from a variety of marginalized sociocultural groups. Historically, children of color, children whose first language is not English, children from low socioeconomic backgrounds, and, in some respects, girls have been served less well in schools than have children who are White, native English speakers, and of middleto upper-class backgrounds. In the 1960s and 1970s, the practice of rationalizing this differential teaching on the basis of presumed "cultural deprivation" produced outrage that led to the formation of multicultural education as a field of study. Today a rich body of theory and research documents how effective education, framed within high expectations for learning, builds on the cultural, experiential, and linguistic resources that children bring with them to the classroom (e.g., Arias & Casanova, 1993; Belenky et al., 1986; Ford, 1996; Gandara, 1995; Ladson-Billings, 1994; McLeod, 1994; Shade, 1989). Multicultural education advocates restructuring school processes around pluralismwhat Grant (1978) has called "an education that is multicultural. " Ideally this entails a holistic restructuring of such processes and structures as curriculum, teaching strategies, grouping of students, assessment of students, and relationships with communities. For example, Banks (1993) examined the knowledge-construction process that frames curriculum in schools, differentiating among various forms of knowledge (personal knowledge, popular knowledge, mainstream academic knowledge, school knowledge, and transformative knowledge) constructed from different social locations (such as Western tradition, an Afrocentric location, a feminist location, or a multicultural
Sorption and Pervaporation of Aroma Compounds Using Zeolite-Filled PDMS Membranes

In view of the pervaporation of aroma compounds from water with PDMS (polydimethylsiloxane) membranes, it was investigated how incorporated zeolites influenced the membrane performance on the level of sorption as well as diffusion. The feasiblilty of the separation process was coupled to a more fundamental study of the importance of functional groups and molecular chain length of the compounds in the feed mixture. The influence of temperature on sorption and pervaporation is included as well as a comparison with commercial membranes. Sorption of aromas in PDMS could be brought in relation to the Hildebrandt parameters. This sorption decreased when adding zeolites to the polymer due to the cross-linking action of the zeolite. Apart from the expected increase in fluxes, increased temperatures induced higher selectivities as well. For the selective removal of ethanol from the aroma mixture, silicalite-filled PDMS membranes were found to be the best.
Crystal structure of tetra-aqua-bis-(pyridine-4-carboxamide-N)-nickel(II) 1,5-naphthalenedisulfonate-isonicotinamide-water (1:2:4), [Ni(H2O)4(C6H6N2O)2][C10H6S2O6]·2C6H6N2O·4H2O, C34H46N8NiO18S2

Abstract C34H46N8NiO18S2, triclinic, P1̄ (no. 2), a = 10.345(7) Å, b = 10.864(5) Å, c = 10.895(3) Å, α = 70.87(3)°, β = 74.96(4)°, γ = 78.21(5)°, V = 1107.6 Å3, Z = 1, Rgt(F) = 0.0453, wRref(F2) = 0.1241, T = 298 K.
Geometry and ordering of defects in non‐stoichiometric rutile

The geometry of point defects in TiO2–x rutile has been investigated using periodic density functional calculations. A reconstruction of the vacancy site with a neighbouring Ti4+-ion displaced to an interstitial site was predicted to be thermodynamically favourable. A similar reconstruction of an interstitial site does not lead to a lower energy. Energies of various ordered patterns of the defects were compared, including that in the shear planes. A particular favourable ordering was found in the (132) shear planes for O-vacancies and in the (121) shear planes for Ti-interstitials. Comparison of the defect formation energies revealed that in highly non-stoichiometric rutile Ti-interstitials are more stable than O-vacancies. However, the difference between the formation energies decreases rapidly as rutile becomes more stoichiometric, indicating that at a very low defect concentrations O-vacancies may be the majority type defect. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
GIAO-PCM Calculations on Alanine Diamide Models Aimed atPredicting Protein Secondary Structures

In this paper we extend our theoretical studies dealing with the dependence of relative proton and carbon chemical shifts (CSs) of protein backbone atoms on their conformational position. In an earlier paper (A. Czajlik, I. Hudaky, A. Perczel, J Comp Chem 2011, 32, 3362) we reported on a fair agreement between calculated and observed backbone CSs as a function of backbone conformation. Applying the polarizable continuum model (PCM) in this work, we compare relative CSs of fully optimized alanine diamide conformers with gas phase calculations and experimental results. Along a path on the Ramachandran surface, we collated calculated relative CSs obtained with and without explicit water molecules, as well as with and without considering the PCM reaction field. Furthermore, we traced the energetically relevant reaction paths along the torsional angle ψ connecting the lowest energy minima (helical, extended, polyproline II and inverse γ-turn) on the Ramachandran plot, with the prospect to facilitate identifying them by their relative CSs. We found that consideration of the solvent effect of the environment around a diamide model improves the agreement with experimental findings on abundant conformers. This agreement is of the level achieved previously by a thorough gas phase investigation on considerably larger oligoalanine models. By relating DeltaδCα, DeltaδHα and DeltaδCβ values of polyproline II and inverse γ-turn to the experimentally well characterized helical and extended data, our calculations contribute to protein secondary structure prediction based on nuclear magnetic CSs
Derivation of the modified molecular gas lubrication equation - a porous media model

A porous media model has been developed which can be applied to ultra-thin gas film lubrication problems encountered in the analysis of a magnetic head slider flying over a magnetic disk coated with giant molecule liquid. In this model, the textured surface coated with giant molecule lubricant is replaced with a permeable material. The appropriate slip-flow boundary conditions, i.e. the high-order slip-flow model, and the proper porous flow model, i.e. the Brinkman-extended Darcy model, are utilized in the gas film and porous film, respectively. The modified molecular gas lubrication (modified MGL) equation is then derived by consideration of the permeability of the running surface. Finally, the effects of porous film thickness (), permeability (K) and inverse Knudsen number (D) on the performance of the magnetic head slider are discussed.
Physiological Determinants of 40-Meter Sprint Performance in Young Male Athletes

This study examined 20 male athletes on a number of physiological variables to determine which may account for the most variation in 40-m sprint performance. The athletes were tested on 40-m sprint, 10-m sprint, a 5-step jump, vertical jump, Wingate anaerobic cycle power, and isokinetic peak torque of the knee and hip at speeds of 1.05, 3.14, and 7.85 rad · sec−1 and ankle at speeds of 1.05, 3.14, and 5.24 rad · sec−1. With R = 0.897 (p ≤ 0.05) and SEE = 0.151 (sec), the 10-m sprint and ankle dorsiflexion peak torque at 5.24 rad · sec−1 were identified as predictors of 40-m sprint performance. With the 10-m sprint removed as an independent variable, stepwise multiple regression was performed again. With R = 0.909 and SEE = 0.146 sec, the 5-step jump, knee flexion peak torque at 7.85 rad · sec−1, and ankle plantar flexion peak torque at 1.05 rad · sec−1 were identified as predictors of 40-m sprint performance. The results indicate that both 10-m sprint and 5-step jump can be used to predict 40-m sprint performance.
Black Wealth/White Wealth: A New Perspective on Racial Inequality

1. Race, Wealth, and Equality 2. A Sociology of Wealth and Racial Inequality 3. Studying Wealth 4. Wealth and Inequality in America 5. A Story of Two Nations: Race and Wealth 6. The Structuring of Racial Inequality in American Life 7. Getting Along: Renewing America's Commitment to Racial Justice.
Adsorption of poly(4-vinylpyridine) N-alkyl quaternized at the chloroform/water interface

The Du Nouy method has been employed to study the interfacial properties of poly(4-vinylpyridine) N-n-alkyl quaternized with hexyl, octyl and decyl bromide, at the chloroform/water interface. The interfacial tension is highly dependent on the hydrophilic–hydrophobic balance between the pyridinium group and the length of the polyelectrolyte side aliphatic chain. The excess interfacial concentration, Γ, is determined according to the Gibbs–Szyszkowski equation. The areas covered by monomer unit at the interface, σ, are smaller than those reported for low molecular weight amphipathic molecules. The linear dependence of with the number of carbon atoms on the side-chain allows the determination of a contribution of just 0.13 kJ for each methylene lateral group and −36 kJ for the vinylpyridinium bromide contributions to . The dependence of the interfacial tension on temperature suggests that the entropy is the main factor determining the adsorption process. Copyright © 2003 Society of Chemical Industry
Hydrogen Production Using Autothermal Reforming of Biodiesel and Other Hydrocarbons for Fuel Cell Applications

The department of Chemical Engineering of the University of Puerto Rico (UPRM) in collaboration with Argonne National Laboratory (ANL) works in the development of a reforming catalyst characterization program. The purpose of this research is to study the viability of using new catalysts to convert Biodiesel, Glycerin and Methanol to a hydrogen rich product gas and compare their production potential, identify the conditions for the accumulation of coke and determine the influence of reactor temperature and water to carbon and oxygen to carbon ratios. A Basket Stirred Tank Reactor (BSTR), Plug Flow Reactor (PFR), Gas Chromatography Mass Spectrophotometer (GCMS) and Gas Chromatography Thermal Conductivity Detector (GCTCD), and Pt and Rh-based catalysts synthesized at ANL were used. During the preliminary ATR experiments, methanol, glycerol and biodiesel showed an increase in H2 production with decreasing O2/C ratio and increases in the reactor temperature. Additionally, Scanning Electron Microscopy (SEM) and EDAX analysis has been performed in some of the catalysts samples. All biodiesel and glycerol experiments performed had shown coke formation. Future research will include, experiments with bio-ethanol and methane as fuel using a Ni-based catalyst synthesized at ANL.Copyright © 2006 by ASME
The Choice Of An Input‐Output Table Embedded In Regional Econometric Input‐Output Models

In this paper, we investigate the role of input-output data sources in regional econometric input-output models. While there has been a great deal of experimentation focused on the accuracy of alternative methods for estimating regional inputoutput coefficients, little attention has been directed to the role of accuracy when the input-output system is nested within a broader accounting framework. The issues of accuracy were considered in two contexts, forecasting and impact analysis focusing on a model developed for the Chicago region. We experimented with three input-output data sources: observed regional data, national input-output, and randomly generated inputoutput coefficients. The effects of different sources of input-output data on regional econometric input-output models revealed that there are significant differences in results obtained in both forecast and impact analyses. The adjustment processes inherent in the econometric input-output system did not mask the differences imbedded in input-output tables derived from different data sources. Since applications of these types of models involve both impact and forecasting exercises, there should be strong motivation for basing the syste on the most accurate set of input-output accounts.
Doping of processable conducting poly(m‐aminophenol) with silver nanoparticles

Processable poly(m-aminophenol) (PmAP) was synthesized using ammonium persulfate (APS) oxidant in 0.6 M sodium hydroxide solution at room temperature. Soluble silver hydroxide ammonium complex was formed by dissolving silver nitrate in excess liquor ammonia and the thermal decomposition of this complex easily produced silver nanoparticle. Then, in situ silver nanoparticle-doped PmAP film was obtained by casting PmAP film from dimethyl sulfoxide (DMSO) with silver hydroxide ammonia complex mixture at 140°C. The nanocomposite was characterized by ultraviolet-visible spectroscopy, Fourier transformed spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy, electron dispersion spectroscopy, thermogravimetric analysis, and X-ray diffraction analysis. The average size of the nanoparticle was around 130–140 nm as confirmed by the TEM analysis. Synthesized PmAP silver nanocomposite showed the highest DC-conductivity of 1.03 × 10−6 S/cm. From the above characterizations, it can be said that silver nanoparticle shows some doping effect on the conductivity of PmAP. The doping level of the silver nanoparticle inside the polymer was optimized in terms of DC-conductivity of the silver nanoparticle-doped PmAP film. Copyright © 2009 John Wiley & Sons, Ltd.
Flow Field Induced Steady Alignment of Oxidized Multi-walled Carbon Nanotubes

The steady ordered micro-ribbons of oxidized multi-walled carbon nanotubes (MWNTs)were obtained through micro-aperture PTFE membrane by vacuum filtration. After treatment by mixture of concentrated nitric acid and sulfuric acid, the surface functional groups modified MWNTs can be easily dispersed to form a homogeneous suspension. It is found that the steady micro-ribbons existed in the films obtained by vacuum filtration of the suspension. The filtration formed steady flow field and induced steady alignment of oxidized MWNTs. The chemical treatment of MWNTs forming strong interaction between MWNTs is necessity to keep steady of the micro-ribbons microstructure.
Determination of the wavelength dependence of refractive indices of flame soot

The spectral variation of the optical properties of soot particles is determined by combining classical and dynamic light scattering measurements with the Kramers-Krönig relations. Particle size and number densities are determined from scattering/extinction and autocorrelation measurements at the wavelength of 0.488 μm. This information is then combined with the spectral extinction measurements in the wavelength range 0.2 to 6.4 μm to determine the spectral variation of the refractive indices of flame soot. Results are presented for a premixed propane-oxygen flame with a fuel equivalence ratio ϕ = 1.8. The sensitivity of the technique and its advantage over the previous methods are discussed.
Measurement and Correlation of Mutual Diffusion Coefficients for Poly(n-Hexyl Methacrylate) + Ketone Systems

Mutual diffusion coefficients for ketones (acetone, methyl ethyl ketone and methyl propyl ketone) in poly(n-hexyl methacrylate) were measured at 313.15, 323.15 and 333.15K by using a sorption apparatus with a quartz spring. The mass-average molecular weight and the glass transition temperature of poly(n-hexyl methacrylate) used in this study were 4×10 and 268.15K, respectively. Solvents were reagent-grade purchased from Wako Chemical Co. Ltd. and were used without further purification. It is found that the mutual diffusion coefficients obtained increase with increasing the temperature and the concentration of solvent , and decrease with increasing the molecular weight of solvent. In addition, the binary mutual diffusion coefficients were correlated by the modified free volume theory. The four parameters of pure polymer and solvent among the eight parameters required in the theory were estimated by applying a method proposed by Iwai et al. The Flory parameters was determined by a least squares method , by using solubility data measured by the same apparatus. The remaining binary three characteristic parameters were determined by fitting the theory to the experimental mutual diffusion coefficient data by use of a nonlinear regression analysis . The correlated results are in good agreement with the experimental data. The modified free volume theory is found to be successful in correlating the mutual diffusion coefficients for ketones in poly(n-hexyl methacrylate).
Mechanisms of Slow Sorption of Organic Chemicals to Natural Particles

The use of equilibrium expressions for sorption to natural particles in fate and transport models is often invalid due to slow kinetics. This paper reviews recent research into the causes of slow sorption and desorption rates at the intraparticle level and how this phenomenon relates to contaminant transport, bioavailability, and remediation. Sorption kinetics are complex and poorly predictable at present. Diffusion limitations appear to play a major role. Contending mechanisms include diffusion through natural organic matter matrices and diffusion through intraparticle nanopores. These mechanisms probably operate simultaneously, but the relative importance of each in a given system is indeterminate. Sorption shows anomalous behaviors that are presently not well explained by the simple diffusion models, including concentration dependence of the slow fraction, distributed rate constants, and kinetic hysteresis. Research is needed to determine whether adsorption/desorption bond energies may play a role alon.