Miracle-dz/UniFAR-FTUs huggingface dataset:
Interaction of water with metal surfaces

A new class of potential suitable for modeling the adsorption of water on different metal sites is described. The new potentials are simple in form and convenient for use in computer simulations. In their real space form they comprise three parts: A pairwise sum of spatially anisotropic 12‐6 potentials, a pairwise sum of isotropic short range potentials, and an image potential. Two modifications of the potential are developed. In the first, the anisotropic potential acts only on the oxygen atom and not on the protons. In the second, the potential acts on all the atoms of the water molecule. In practical calculations it is convenient to transform the potential to a reciprocal space form in the manner described by Steele [Surf. Sci. 36, 317 (1973)]. Adsorption of water at top, bridge, and hollow sites on (100), (110), and (111) surfaces of Pt, Ni, Cu, and Al were studied using two fitting parameters and the results compared with previous theoretical calculations.
Brassylic Acid: Chemical Intermediate from High-Erucic Oils

Techniques and information derived from laboratory studies of a two-stage cleavage of erucic acid with ozone and oxygen have been translated to a small pilot-scale operation to produce brassylic acid (72-82 % yield) of high purity (99 %) with pelargonic acid as a coproduct. The initial ozonolysis phase is yield-limiting while the second stage oxidation of ozonolysis intermediates appears to be quantitative. A preliminary cost estimate has been prepared for production of polYJTler-grade brassylic acid from Crambe abyssinica seed oil. The effects of bye product credit and crambe oil cost on the net cost-to-make brassylic acid are illustrated.
Assessing of a New Customer Services System’s Use in Internet Environment

: Assessing use is very important for organizations selling and using customer services system in Internet environments. Based on a conceptual model, this paper is to empirically study individuals’ assessments of a new customer services system in Internet environment. The model has three phases; pre-use, test and use. In relation to the three phases, the concepts of value and quality are discussed. The main contribution of this paper is the understanding of the difference between the concepts of value and quality being illustrated in the conceptual model. Customers’ assessment of value and quality could have implications for companies developing new customer services system in Internet environments.
Liquid – Liquid Extraction and Pertraction of Eu(III) from Nitric Acid Medium Using Several Substituted Diglycolamide Extractants

Solvent extraction and supported liquid membrane (SLM) transport properties of Eu(III) from nitric acid feed conditions were investigated using several substituted diglycolamide (DGA) extractants such as N,N,N′N′-tetra-n-octyl diglycolamide (TODGA), N,N,N′N′-tetra(2-ethylhexyl) diglycolamide (T2EHDGA), N,N,N′N′-tetra-n-hexyl diglycolamide (THDGA), N,N,N′N′-tetra-n-pentyl diglycolamide (TPDGA), and N,N,N′N′-tetra-n-decyl diglycolamide (TDDGA). Effects of feed acidity and phase modifier composition on Eu(III) extraction were investigated using the DGAs and the nature of extracted species were ascertained by slope analysis method. The Eu(III) distribution ratio (DEu) values were found to decrease in the presence of iso-decanol. In general, the DEu values decreased with increased alkyl chain length of the DGA. The extracted species contained only 2 extractant molecules when TPDGA and TDDGA were used while for TODGA about four extractant molecules were found to be present in the extracted species. The supported liquid membrane transport of Eu(III) was studied under varying experimental conditions using the five DGA extractants. Transport studies using 0.1 M DGA as the extractant suggested the trend as TDDGA > TODGA > T2EHDGA ∼ THDGA which significantly changed to TPDGA > THDGA > TODGA > TDDGA > T2EHDGA in the presence of 30% iso-decanol as the phase modifier. The permeability coefficient (P) values were also determined with membranes of varying pore sizes.
Surface-Enhanced Raman Scattering Investigation of Hollow Gold Nanospheres

Hollow gold nanospheres (HGNs) provide a tunable surface plasmon resonance from 550 to 820 nm by controlling their inner diameter and wall thickness. Although they have been used for biological imaging based on their optical properties in the near-infrared region, their surface-enhanced Raman scattering (SERS) performance has not been thoroughly studied. Herein, HGNs with different surface plasmon resonances were synthesized and functionalized with different Raman reporters. HGNs coupled with Raman reporters, on and off resonant with the laser excitation wavelength, were systematically interrogated in isolated and partially aggregated situations. HGNs with thicker shells generated higher SERS responses than thinner shells no matter whether they were isolated, or partially aggregated, or whether their surface plasmon resonances were resonant with the excitation wavelength or not. This study gives insight into the basis of the SERS properties for these kinds of materials.
Axial Variation of Mass Transfer Volumetric Coefficients in Bubble Column Bioreactors

Bubble column bioreactors used to perform aerobic fermentations consist of a liquid medium containing microorganisms that uptake oxygen for metabolic reactions and gas bubbles that supply this oxygen. Mass transfer rate from gas to liquid phase is a crucial factor for the performance of bioreactors because microorganisms life and metabolic reactions depend directly upon it. The maximum transfer rate of oxygen from gas bubbles to the liquid medium is a function of two important parameters: the specific interfacial area and the mass transfer coefficient. These two parameters are lumped into the volumetric specific transfer coefficient. Since size of gas bubbles is not constant along the bioreactor, gas-liquid mass transfer rate changes continuously. In order to optimize mass transfer rates, it is essential to know the bubble size distribution and the interfacial phenomena in each particular system at different operating conditions. Due to the complexity of hydrodynamics and bubble interphase characteristics, the current state of the problem does not consider a universal model to evaluate mass transfer rates in gas-liquid systems; moreover, information about bubble size and its distribution is often neglected. This work presents a model to evaluate axial distribution of values of volumetric mass transfer coefficients considering changes in bubble size and its influence on bubble area along the reactor in homogeneous regime. Simultaneously, this model evaluates changes of volumetric mass transfer coefficient and its effect on the fermentation kinetics, which influences performance of the bioreactor.
Laser-induced photoacoustic calorimetric determination of enthalpy and volume changes in photolysis of 5′-deoxyadenosylcobalamin and methylcobalamin

Photolysis of 5′-deoxy-5′-adenosylcobalamin (AdoCbl) in neutral aqueous solution and methylcobalamin (MeCbl) in neutral and acid aqueous solution has been investigated using pulsed, time-resolved photoacoustic calorimetry in the temperature range 10–30 °C. The enthalpy changes for the above cobalamins, 129 ± 17, 163 ± 21 and 176 ± 23 kJ mol–1, respectively, are consistent with the values obtained by thermolytic kinetic methods. The reaction volume changes for them, 6 ± 1, 2 ± 0.5 and 5 ± 1 ml mol–1, respectively, are probably due to the conformational changes of the corrin ring and its side chains accompanying Co–C bond cleavage.
Synthesis of Some New [1,8]Naphthyridine, Pyrido[2,3-d]-Pyrimidine, and Other Annulated Pyridine Derivatives

2-Aminopyridine-3-carbonitrile derivative 1 reacted with each of malononitrile, ethyl cyanacetate, benzylidenemalononitrile, diethyl malonate, and ethyl acetoacetate to give the corresponding [1,8]naphthyridine derivatives 3, 5, 8, 11, and 14, respectively. Further annulations of 3, 5, and 8 gave the corresponding pyrido[2,3-b][1,8]naphthyridine-3-carbonitrile derivative 17, pyrido[2,3-h][1,6]naphthyridine-3-carbonitrile derivatives 18 and 19, respectively. The reaction of 1 with formic acid, formamide, acetic anhydride, urea or thiourea, and 4-isothiocyanatobenzenesulfonamide gave the pyridopyrimidine derivatives 20a,b, 21, 22a,b, and 26, respectively. Treatment of compound 1 with sulfuric acid afforded the amide derivative 27. Compound 27 reacted with 4-chlorobenzaldehyde and 1H-indene-1,3(2H)-dione to give the pyridopyrimidine derivative 28 and spiro derivative 30, respectively. In addition, compound 1 reacted with halo compounds afforded the pyrrolopyridine derivatives 32 and 34. Finally, treatment of 1 with hydrazine hydrate gave the pyrazolopyridine derivative 35. The structures of the newly synthesized compounds were established by elemental and spectral data.
An Inverse Heat Transfer Approach to Mitigating Sources of Experimental Error in Transient Heat Transfer Experiments

The Inverse Flux Solver for Arbitrary Waveforms (IFSAW) algorithm is a transient, simultaneous solution of time resolved adiabatic effectiveness, η(t), and heat transfer coefficient, h(t). Numerical simulations showed IFSAW maintained its high accuracy despite two experimental sources of error typically found when using a transient heat transfer method. The traditional transient method involves exposing a film cooled wind tunnel model at uniform temperature to a step change in freestream temperature. The experimental design results in nearly one-dimensional heat transfer and allows the surface to be modeled as semi-infinite. Typically, the surface temperature history is correlated to an analytical solution to the governing heat transfer equation (yielding η and h), but the required temperature step change is impossible to achieve in a laboratory. This paper first analyzed the error introduced by imperfect step changes and evaluated an alternative methodology, IFSAW, requiring only an arbitrary change in freestream temperature occurring at any rate. Secondly, severe error in h (found in locations where η is near unity because the surface temperature changes little from the initial temperature) was shown to be mitigated using IFSAW combined with a gradual change in coolant temperature at any point during measurement. With both complications, IFSAW maintains its ability to determine periodic η(t) and h(t) waveforms. In these ways, IFSAW is shown to be superior to the legacy transient method. © 2013 ASME
Finite-size and surface effects on the glass transition of liquid toluene confined in cylindrical mesopores

Some of the most regular porous silicates (MCM-41 and SBA-15), with several different pore diameters from 2.4 to 8.7 nm, are used to study the van der Waals fragile liquid toluene in confined geometry. We measure two major macroscopic signatures of a glass transition, i.e., a discontinuous change in the heat capacity and in the thermal expansion, by adiabatic calorimetry and neutron scattering experiments. A nontrivial size dependence of the glass transition features, most notably a nonmonotonic variation of the mean glass transition temperature, is observed. The range of the glass transition is found extremely broad. This supports the notion of competition between surface boundary conditions and cutoff or finite-size effects.
Time-resolved polarization-sensitive measurements of the electric field in a sliding discharge by means of dc-field-induced coherent Raman scattering

We investigate the properties of the IR signal generated through coherent Raman scattering involving the Q(1) transition of a hydrogen molecule in the presence of the quasi-static electric field of the sliding discharge propagating along a ferrite surface in a hydrogen atmosphere. The results of time-resolved polarization- sensitive measurements performed on this signal are employed to determine the parameters of the electric field in the sliding discharge. These measurements have shown, in particular, that the propagation of the discharge leader along the ferrite surface is accompanied by the rotation of the vector of the quasi-static electric field.
Extractive metals from metallic powders recovered from waste printed circuit boards

Abstract Leaching behaviours of metallic powders were investigated using electrically generated chlorine at the anode chamber containing sulphuric acid solution, NaCl and CuSO4. Various parameters, which included the solid/liquid ratio, current density, concentration of NaCl, CuSO4, and H2SO4, leaching temperature, particle size, and stirring speed, were studied to understand the mechanism of leaching metallic powders. The capability of dissolved metallic powders increased with the increase in all parameters except the solid/liquid ratio. Leaching metallic powders were transport-controlled with a low activation energy of 14·7 kJ mol−1. The dissolved copper could be transferred from the anodic chamber to the middle chamber by solvent extraction technology. In the electric field, copper ions are transferred from the middle chamber to the cathodic chamber through a cation exchange membrane (CEM) and electrodeposited to form copper foils. The tensile strength and elongation percentage of 65 μm-thick copper foils were 276 Mpa and 10·66%, respectively. The utilisation of metallic powders recovered from waste PCBs (WPCBs) could produce high-performance copper foil. On a examiné le comportement de lixiviation de poudres métalliques en utilisant du chlore engendré par électricité dans la chambre de l’anode contenant une solution d’acide sulfurique, du NaCl et du CuSO4. On a étudié une variété de paramètres, incluant le rapport solide à liquide, la densité de courant, la concentration de NaCl, de CuSO4 et d’H2SO4, la température de lixiviation, la taille de particule et la vitesse d’agitation, afin de comprendre le mécanisme de lixiviation des poudres métalliques. La capacité des poudres métalliques dissoutes augmentait avec l’augmentation de tous les paramètres, sauf le rapport solide à liquide. Les poudres métalliques de lixiviation étaient contrôlées par le transport, avec une faible énergie d’activation de 14·7 kJ/mol. On pouvait transférer le cuivre dissous de la chambre anodique à la chambre du milieu au moyen de la technologie d’extraction par solvant. Dans un champ électrique, les ions de cuivre étaient transférés de la chambre du milieu à la chambre cathodique par une membrane d’échange de cation et étaient déposés par galvanoplastie pour former des feuilles de cuivre. La résistance à la traction et le pourcent d’élongation de feuilles de cuivre de 65 μm d’épaisseur étaient respectivement de 276 MPa et de 10·66%. Les poudres métalliques récupérées de cartes de circuit imprimé de rebut pourraient produire une feuille de cuivre à haute performance.
Small-angle neutron scattering of concentrated adhesive-hard-sphere dispersions

Small-angle neutron-scattering experiments were performed on concentrated dispersions of sterically stabilized silica particles dispersed in benzene, where the particles show an effective attraction on lowering the temperature. In this study, the system was cooled down from 52 C, where almost-hard-sphere behavior is observed, to just above the phase transition temperature at 33 C in seven steps. At each temperature, scattered intensities were measured at four volume fractions up to 0.28. The constancy of the particle form factor allowed data analysis at the level of structure factors. Experimental data were fitted with model calculations using the Percus-Yevick solution for Baxter's adhesive hard-sphere potential, taking the particle size polydispersity into account. A quite satisfactory model description of the experimental structure factors could be obtained. At lower temperatures and higher volume fractions, the fits are even quantitative. The obtained stickiness parameter is directly related to sample temperature, and it does not depend on volume fraction. These observations confirm the model of a short-ranged attraction between the particles, with a well depth governed by enthalpic and entropic contributions to the chain-chain and chain-solvent interactions.
Organometallic Block Copolymers as Catalyst Precursors for Templated Carbon Nanotube Growth

The use of organic-organometallic block copolymers as catalyst precursors for templated carbon nanotube (CNT) growth (see Figure) is demonstrated for the first time. A thin film of block copolymer was treated with O2 plasma to produce ordered iron-containing catalyst nanoparticle arrays, which are efficient catalysts for CNT growth. This approach allows control of catalyst domain size and spacing by tailoring block copolymer composition.
Surface-Grafted Hyperbranched Polymers via Self-Condensing Atom Transfer Radical Polymerization from Silicon Surfaces

A novel synthetic concept for preparing hyperbranched polymers on a planar surface is described, in which a silicon wafer grafted with an initiator layer composed of an α-bromoester fragment is used for a self-condensing vinyl polymerization (SCVP) via atom transfer radical polymerization (ATRP). A large number of nanoscale protrusions were found on the surface obtained by (meth)acrylic AB* initiator-monomers (“inimers”). The variations of the size and density of the protrusions, as well as the film thickness, depend on the catalyst system and show a slight correlation with the degree of branching and molecular weight of the ungrafted polymers, as confirmed by scanning force microscopy (SFM). The surface roughness is much larger than that of polymer brushes obtained by polymerizing conventional (meth)acrylates. The copolymerization of an AB* inimer and a conventional vinyl monomer gave an intermediate surface topography between the polymer protrusions and the polymer brush, which may be due to the highly .
Synthesis and physical properties of ferrocene derivatives XXIV: structural study of liquid crystalline mono-substituted ferrocene derivatives

Crystal structures of mono-substituted ferrocene derivatives,ω-[4-(4-methoxyphenoxycarbonyl)phenoxy]alkoxycarbonyl ferrocene (mMAF-n, n = 3-8, 11, where n is the number of carbon atoms in the alkyl spacer), are newly determined. The molecular structures of mMAF-n are divided into three groups; (i) a bent shape containing a doublegauche conformation (n = 2, 4, 6), (ii) a linear shape containing a kink (n = 3, 5, 7), and (iii) an extended linear shape adopting an all-trans conformation (n = 8, 11). The difference of the molecular shape between group (i) and (ii) is highly correlated with the parity of the number of carbon atoms in the alkyl spacer (odd-even effects). In both group (i) and (ii), the high entropic contribution of gauche conformations is introduced in the alkyl spacer, which is consistent with the non-liquid crystallinity of mMAF-n (n = 2-7). In group (iii), it is found out that there is a border at mMAF-8 on the mesomorphism of mMAF-n (n = 2-12).
The status of heavy metal levels in a Ramsar site, Kuala Gula bird sanctuary: the impact of the anthropogenic inputs

Distributions of Cd, Cu, Pb, and Zn in the surface sediments from two sites of the Kuala Gula Bird Sanctuary, Malaysia were monitored for a period of 6 months from October 2006 to March 2007. In December 2006, the concentration of Zn in one location was significantly (p < 0.05) higher (3.9 ± 1.3 mg kg−1) than the other metals at both sites, but in the oxidizable organic fraction it was highest at both sites during October; with mean concentrations of 18 mg kg−1 at both locations. In the acid-reducible fraction, high concentrations of Pb (2.3 mg kg−1) were detected at station 2 in February 2007, being highest among all four metals at both stations. The acid-reducible fraction found in Pb ranged from 0.10% to 3.1% in both stations. Percentages ranging from 51% to 96% were observed for all four metals in the resistant fraction throughout the sampling period. These results indicate low contributions from anthropogenic sources. The findings constitute a baseline data archive for future reference.
Channel Sediment Characterization and Evaluation of the Potential Impact of Iron-Rich Phases on the Use of Sediments in Brick Production

Abstract Using data collected at both room temperature and higher temperatures, this study examined the mineralogy of, and iron coordination shell in, polluted sediments from drainage and irrigation channels. As a part of the study, mineralogical characteristics of iron phases of canal sediments were examined to determine if these sediments could be used in place of common clays for the production of bricks. While such use would reduce the impact of these wastes on the environment, an excess of iron in these sediments could affect some important features of bricks. Therefore, this study examined the oxidation state of iron as well as its structural location in the mineral matrix. X-ray powder diffraction, thermal analysis, and X-ray absorption spectroscopy were used to examine sediments and bricks manufactured from irrigation and drainage channels of the Po River region in northeast Italy. Results indicated that canal sediments can be used as row materials in clay brick production. In fact, the process te.
Error estimates on bond‐length and angle corrections from TLS analysis

Librational motion within a crystal structure distorts the measured bond distances and angles from their physical values. TLS analysis of a rigid molecule or a rigid part of a molecule allows the calculation of bond-length and angle corrections. Until now, no estimate of the error on these corrections has been available. A method is presented for propagating the errors on the anisotropic displacement parameters (ADPs) to the bond-length and angle corrections which are a function of the libration tensor. The numerical significance of approximations made during the calculation is discussed.
Silicon nanopillars formed with gold colloidal particle masking

Silicon nanopillars were fabricated by a novel natural lithography technique utilizing a gold colloidal particle monolayer as an etch mask. Using SiCl4 based reactive ion etching (RIE), silicon nanopillars with high density and uniformity in height and shape were obtained with 15 and 10 nm diam gold colloidal particles. The uniform pillars obtained from the 15 nm colloidal gold etch mask were subsequently sharpened to less than 5 nm diam tips by oxidation. 5 nm diam colloids were used to obtain nonuniform 5 nm diam pillars directly by RIE, but with 2 nm colloids the limit of pillar formation was reached. The pillars were also fabricated in selected areas by lithographic patterning of the substrate.
First principles study on interfacial electronic structures in exchange-spring magnets

We study the magnetic properties of Nd2Fe14B/α-Fe multilayer systems, especially the exchange coupling between the two layers and the crystal field parameters A02⟨r2⟩ for the Nd ions located around the interfaces, based on first principles calculations. We find that the exchange coupling depends on the Miller indices of the crystallographic planes at the interface, and can be negative which favors anti-parallel alignment of the magnetizations of the hard- and soft-magnet layers.
Solvothermal Synthesis of CoO, Co 3 O 4 , Ni(OH) 2 and Mg(OH) 2 Nanotubes

In this paper, CoO, Co3O4, Ni(OH)2, and Mg(OH)2 nanotubes were synthesized by solvothermal treatment of corresponding colloidal hydroxide. These nanotubes were characterized by powder X-ray diffraction (XRD), selected area electron diffraction (SAED), and transmission electron microscopy (TEM). According to the time-dependent morphology evolution, it is likely that the growth is governed by a solution−solid process. Advantages of this method include that it is a simple and general process without the need for a catalyst, surfactant, or template, which makes it low cost, and that the raw materials are readily available. On the basis of the above results, other metal hydroxides with layered structure are therefore potentially capable of forming nanotubes.