Miracle-dz/UniFAR-FTUs huggingface dataset:
Fragmentation of a single molten metal droplet penetrating into sodium pool. IV. Thermal and hydrodynamic effects on fragmentation in copper

To characterize the relationship between thermal and hydrodynamic effects on fragmentation of molten metallic fuels, with the interaction of the sodium coolant under a wide range of thermal and hydrodynamic conditions, in this paper, we focus on the fragmentation characteristics of a single molten copper droplet (1 and 5 g) with an ambient Weber number (We a) from 102 to 614 and superheating conditions from 15 to 574°C, which penetrates into a sodium pool at an initial temperature from 298 to 355°C. In our experiments, fine fragmentations of the single molten copper droplets with a high We a were clearly observed even under a supercooled condition that is well below the copper melting point of 1083°C. The dimensionless mass median diameters (D m /D 0) of molten droplets with a high We a are less than the molten droplets with a low We a under the same thermal condition. When We a was approximately >200, the hydrodynamic effect on fragmentation became dominant over the thermal effect under a relatively low superheating condition. For a higher We a range, the comparisons indicated that the fragment sizes of the molten copper droplets had similar distributions to those of copper and metallic fuel jets and stainless steel droplets even with different thermophysical properties and a 1000-fold mass difference, which implied the possibility that the fragment size characteristics of the molten metal jets could be evaluated by the interaction of a single droplet with the sodium coolant without consideration of dropping modes and mass.
Effect of hulling and milling on the physical properties of rice grains

Basic physical properties of agricultural materials play important role for optimizing the design of equipment and fa- cilities for the harvesting, handling, conveying, separation, drying, storing, and processing. In this study, some physical properties of three rice varieties, namely Tarom Mahali, Fajr, and Neda, at three levels of processing, which name rough rice (paddy), brown rice (husked or hulled), and white rice (milled) were investigated. The thousand grains mass and porosity decreased significantly with the rice processing, but the bulk density increased. The rough rice of each variety showed the least value of true density. Unit mass and volume of rice grain decreased with the rice processing. Totally, the static coefficient of friction affected by cultivars, levels of pro- cessing, and frictional materials. By processing, the filling angle of repose for all cultivars decreased. The terminal velocity increase significantly for every variety. It was observed that the terminal velocity of the rice's hull and bran is lower than for the rough rice, brown rice, milled rice.
Melting in Trivalent Metal Chlorides

We report a neutron diffraction study of the liquid structure of YCl3 and combine the structural data with macroscopic melting and transport data to contrast the behaviour of this molten salt with those of SrCl2, ZnCl2 and AlCl3 as prototypes of different melting mechanisms for ionic materials. A novel melting mechanism for trivalent metal chlorides, leading to a loose disordered network of edge-sharing octahedral units in the liquid phase, is thereby established. The various melting behaviours are related to bonding character with the help of Pettifor's phenomenological chemical scale.
Mass Changes during Adsorption of Metal Bipyridyl Complexes by Clay Films Monitored with an Electrochemical Quartz Crystal Microbalance

The adsorption of [M(bpy)3]2+ ions (M = Ru or Os) by clay films immersed in pure water and in electrolyte solutions was investigated by electrochemical quartz crystal microbalance (EQCM), UV-visible spectroscopy and powder X-ray diffraction. In water, the adsorption of the cations resulted in a decrease in the mass of the films. This decrease in mass is attributed to the expulsion of some 50 water molecules from the clay interlayer spaces for each cation adsorbed. Water is lost to make room for the large metal complex cations in the interlayer spaces, and because of decreases in the volume of the interlayer spaces during adsorption of the cations. In 0.05 M NaCl or 0.05 M Na2SO4, UV-visible measurements show a rapid initial adsorption of the cations by ion exchange, followed by a slower additional adsorption of the cations above the clay’s CEC, presumably as ion pairs with the electrolyte counter ions. The EQCM show initial reductions in the mass of the films that were two to three times larger in pure water. These initial mass decreases were followed by smaller mass ‘re-increases’ at longer times that were not observed in water. The larger initial mass losses are attributed to the loss of more water from the clay interlayer spaces. In 0.5 M Na2SO4 or 1.0 M NaCl, adsorption of the cations never exceeded the clay’s CEC. The initial decreases in mass upon addition of the cations all but disappeared, leaving only the smaller positive mass changes at longer times.
A New Strategy for the Synthesis of Polyaniline Nanostructures: From Nanofibers to Nanowires

A new approach for the synthesis of polyaniline (PANI) nanostructures under UV light illumination has been developed, which is the first report of a templateless chemical process for preparing pure PANI nanowires. The acceleration effect of photo-assistance on the polymerization can promote the homogeneous nucleation and elongation of the nanofibers and nanowires, leading to easy preparation of tunable diameters of the nanowires and nanofibers of PANI.
Adsorption of Ammonia on Ozonated Activated Carbon

In this theoretical research, we investigated ozonated granular activated carbon (OGAC) as an ammonia adsorbent in aqueous systems. Research objectives were to determine the (1) effectiveness of ozone loading on adsorption capacity of activated carbon in aqueous ammonia solutions, (2) kinetics and adsorption isotherms of ammonia adsorption, and (3) effect of volatile organic compounds on adsorption of ammonia from the aqueous phase. Batch experiments indicated that ozonation for 30 min enhanced the adsorption capacity of granular activated carbon from 0.47 ±0.065 mg g-1 to 1.02 ±0.099 mg g-1 due to increased surface oxygen species on activated carbon. These results suggested that activated carbon could be chemically modified to enhance the adsorption of ammonia from aqueous systems. Analysis of the rate data suggested that the adsorption of ammonia on OGAC followed an Elovich model with initial adsorption rate (a) and desorption constants (s) between 0.146 and 1.06 mg g-1 min-1 and 5.5 and 7.75 g mg-1, respectively (25°C to 45°C). The effect of temperature (25°C to 45°C) on adsorption was not found to be significant, suggesting that adsorption on OGAC was non-activated. However, presence of volatile organic compounds (VOCs) such as p-cresol and acetic acid inhibited adsorption of ammonia on OGAC. Future research is needed to synthesize activated carbon that can absorb ammonia and VOCs simultaneously.
Physical and electrochemical characterization of reduced graphene oxide/silver nanocomposites synthesized by adopting a green approach

This study demonstrates the physical and electrochemical characterization of nanocomposites based on reduced graphene oxide (RGO) and silver nanoparticles (Ag NPs) synthesized by adopting a green and low cost approach using lactulose as a reducing and stabilizing agent. The RGO/Ag nanocomposites were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, UV-vis absorption spectroscopy and transmission electron microscopy (TEM) to obtain clear information about the removal of functional groups and morphology of nanocomposites. XRD results confirmed the formation of a high purity crystal of Ag on RGO. FTIR results established partial reduction of GO to RGO by lactulose. TEM images show that spherical Ag NPs of an average size of 4 nm are uniformly deposited onto RGO sheets and also prevent the restacking of RGO layers. The energy dispersive X-ray spectra (EDX) of RGO/Ag nanocomposites indicate the presence of Ag and graphene. Also, EDX spectra of FESEM show that Ag content increases with the increasing concentration of AgNO3 in RGO/Ag nanocomposites. The surface charge as well as stability of the nanocomposites is examined by measuring the zeta potential while electro-conductivity is measured by potentiostat–galvanostat. The zeta potential and conductivity of RGO/Ag nanocomposites is greatly improved compared to GO and RGO. The electro-conductivity of RGO/Ag nanocomposites indicates that conductivity of RGO/Ag nanocomposite increases with increasing concentration of Ag. The electrochemical result also indicates the presence of a higher amount of ionic functional groups in GO than those in RGO and RGO/Ag nanocomposites. GO indicates the lowest current which gradually increased for RGO and RGO/Ag nanocomposites, respectively.
The modulated structure of synthetic Co-åkermanite, Ca2CoSi2O7

Diffraction patterns of synthetic Co-akermanite, Ca 2 CoSi 2 O 7 , reveal distinct satellite reflections at room temperature. An incommensurate modulation in this material has been determined by five-dimensional refinement pf the structure. The basic structure is tetragonal P42 1 m, unit-cell dimensions a=7.8417 (6), c=5.0249 (3) A, V=308.99 A 3 , Z=2, M r =307.26, D m =3.307 (4) g cm -3 at 293 K, D x =3.302 g cm -3 , Mo Kα with graphite monochromator, μ=47.7 cm -1 , F(000)=302, R=0.049 for 734 unique reflections
Anthocyanins in the Lowbush Blueberry, Vaccinium angustifolium

SUMMARY Fifteen anthocyanin pigments were isolated from the lowbush blueberry, Vaccinium angustifolium Ait. , and identified by chromatographic, spectral, and chemical properties. The 3-monoglucosides and 3-monogalactosides of delphinidin, malvidin, petunidin, peonidin, and cyanidin were isolated; also present in small quantities were the 3-monoarabinosides of the same five anthocyanidins. The glucosides were present in much greater quantity than the galactosides or the arabinosides. Several diglycosides were also present, but in quantities too low for identification.
First-principles calculation of vibrational frequencies for monoclinic tribismuth borate BiB3O6

Monoclinic BiB3O6 is an excellent nonlinear optical material with many advantages compared to other borate crystals. As one part of understanding the properties of BiB3O6, the harmonic frequencies of BiB3O6 are calculated by applying the numerical-difference technique based on first-principles gradient-corrected hybrid B3PW density functional theory electronic structure calculations within the Gaussian-orbital-based CO-LCAO scheme. The complete 13A and 14B vibrational modes are assigned, graphically visualized and classified according to the Bi—O and B—O motions. Comparisons with previous experimental reports are discussed in detail.
Zr-based bulk metallic glass as a cylinder material for high pressure apparatuses

Zirconium-based bulk metallic glass (Zr-based BMG) has outstanding properties as a cylinder material for piston-cylinder high pressure apparatuses and is especially useful for neutron scattering. The piston-cylinder consisting of a Zr-based BMG cylinder with outer/inner diameters of 8.8/2.5 mm sustains pressures up to 1.81 GPa and ruptured at 2.0 GPa, with pressure values determined by the superconducting temperature of lead. The neutron attenuation of Zr-based BMG is similar to that of TiZr null-scattering alloy and more transparent than that of CuBe alloy. No contamination of sharp Bragg reflections is observed in the neutron diffraction pattern for Zr-based BMG. The magnetic susceptibility of Zr-based BMG is similar to that of CuBe alloy; this leads to a potential application for measurements of magnetic properties under pressure.
Modelling the nanoscale patterning of nucleic acid base pairs deposited on graphite

Interactions between graphite and nucleic-acid base pairs are investigated. An existing polarizable potential that uses distributed multipoles up to and including quadrupoles is extended to describe the graphite surface and the nucleic-acid bases cytosine and guanine. Adsorption energies and structures calculated with this potential are compared with data obtained using electronic structure theory. Structures of co-adsorbed cytosine and guanine layers are optimised and two competing arrangements, the ‘dimer-row’ and ‘quartet-row’ patterns, are compared with experimental scanning tunnelling microscopy images. We include two factors not considered in previous studies: the presence of the graphite surface and the inter-row packing. However, our findings agree with previous calculations in that the ‘quartet-row’ is energetically preferred, despite STM experiments suggesting the ‘dimer-row’ structure is observed.
A molecular field treatment of liquid crystalline mixtures

The Maier-Saupe theory of the nematic mesophase is extended to multicomponent systems containing axially symmetric molecules interacting with a general anisotropic intermolecular potential. Expressions are derived for the anisotropic pseudo-potential of each component as well as the orientational molar Helmholtz function for the mixture. Simplified forms of these formulae are then employed, with some success, to predict the phase diagrams for two binary mixtures of nematogens. The possible application of the theory to interpret the solute activity coefficients determined by gas-liquid chromatography using a nematogen as the stationary phase is indicated.
Numerical and experimental investigation of melting of ice involving natural convection

Two‐dimensional transient melting of ice in a rectangular enclosure was numerically and experimentally investigated. Natural convection in the liquid phase due to the temperature dependency of water density was considered in the numerical model. The implicit finite difference method with fixed staggered grid approach was utilized. The SIMPLER algorithm was followed for the solution of pressure and velocity fields in the liquid phase. The prediction of the model was found to be satisfactory through preliminary experimentation. Copyright © 2002 John Wiley & Sons, Ltd.
Propane dehydrogenation on chromia/silica and chromia/alumina catalysts

The catalytic activity of CrOx/SiO2 (SC, 0.08 to 0.99% chromium by weight), CrOx/Al2O3 (AC, 0.16 to 1.55%), and α-Cr2O3 for the dehydrogenation of propane has been investigated at 723 to 823 K in a flow apparatus. Before catalytic experiments, SC and AC samples were activated with oxygen at 773 K (s.o. treatment) followed or not followed by reduction with CO or H2 at 623 K. Occasionally, SC samples were dehydrated under vacuum at 1023 K before the s.o. treatment. Assuming all chromium to be in the +6 state after s.o. , the average oxidation number of chromium (n) is n ≍ 2 in SC samples reduced with CO and n ≍ 3 with H2. In AC catalysts, n values progressively increase in consecutive reduction experiments, from n = 2.2 to n = 4.2. All catalysts are highly selective to propene and undergo a deactivation process during time on stream. The s.o. treatment completely restores the activity. The reduction mode does not influence the catalytic activity. Surface species formed upon adsorption at room temperature (RT) of CO or NO were studied by IR spectroscopy on CrOx/SiO2 submitted to treatments analogous to those used before catalytic experiments. In SC catalysts reduced with CO, the formation of carbonyls and nitrosyls of three different CrII species was confirmed. Interestingly, all these species were absent when the sample was (i) reduced with H2 at 773 K, or (ii) heated with H2O after reduction with CO, or (iii) exposed to propane after reduction with either CO or H2. After treatments (i) through (iii), a carbonyl and a dinitrosyl of CrIII were the only species formed on CO or NO adsorption at RT. Relying on (i) the dependence of the activity on chromium content, (ii) IR results. and (iii) ESR data, it is suggested that mononuclear CrIII with two coordinative vacancies is the active site for the dehydrogenation of propane. The catalytic activity of CrOx/SiO2, CrOx/Al2O3, and α-Cr2O3 is compared with that of CrOx/ZrO2, measured previously. Possible reasons for the substantially higher activity of CrOx/ZrO2 are discussed.
Influence of chemical treatment on the tensile properties of kenaf fiber reinforced thermoplastic polyurethane composite

In this study, the effect of polymeric Methylene Diphenyl Diisocyanate (pMDI) chemical treatment on kenaf (Hibiscus cannabinus) reinforced thermoplastic polyurethane (TPU/KF) was examined using two different procedures. The first consisted of treating the fibers with 4% pMDI, and the second involved 2% NaOH + 4% pMDI. The composites were characterized according to their tensile properties, Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The treatment of the composite with 4% pMDI did not significantly affect its tensile properties, but the treatment with 2% NaOH + 4% pMDI significantly increased the tensile properties of the composite (i.e., 30 and 42% increases in the tensile strength and modulus, respectively). FTIR also showed that treatment with 2% NaOH + 4% pMDI led to the strongest H-bonding. Additionally, the surface morphology of specimens after tensile fracture confirmed that the composite treated with 2% NaOH + 4% pMDI had the best adhesion and wettability.
Two-Region Average Model for Cuttings Transport in Horizontal Wellbores I: Transport Equations

Abstract The aim of this article is to derive a mathematical model without length-scale restrictions for cuttings transport in horizontal wellbores using the non-local forms of the volume averaging method, which is a technique used to derive transport equations for multiphase systems and one of the main approaches in two-phase flow modeling. The theoretical derivation of the cuttings transport problem is for a two-region system composed of a fluid bed (ω region) and a stationary bed (η region) of drill cuttings that it is considered as a porous medium. The volume-averaged mathematical model obtained in this work consists of the mass and momentum equations for the ω and η regions. The model was the starting point to obtain one-equation models for both regions. The one-equation models together with adequate jump conditions can be used to predict the hydrodynamics of the ω and η regions. The mathematical derivations of the momentum and mass flux transfer jump conditions are presented in Part II of this article.
Gas sorption and transport in polyisobutylene: Equilibrium and nonequilibrium molecular dynamics simulations

Molecular dynamics calculations are reported on the sorption and diffusion of small gas molecules (He, H2, and O2) in amorphous polyisobutylene. An all‐atom force field (with explicit hydrogen atoms) was used. In addition to the standard method of obtaining the diffusion coefficient from an equilibrium calculation via the mean‐square displacement we used a nonequilibrium technique that applies a fictitious external field selectively to the gas molecules. To our knowledge, nonequilibrium MD is, for the first time, applied to the problem of gas diffusion in polymers. Results of both techniques are compared. Energy profiles of the jump events underlying gas diffusion through polymers are studied. We also discuss the possible presence of anomalous (non‐Einstein) behavior of gas molecules diffusing through an amorphous polymer. Gas solubilities in polyisobutylene are calculated by particle‐insertion techniques.
The Influence of Service Quality on Clients’ Satisfaction and Its Effect on Their Loyalty at PT Bank Aceh, Medan Branch

PT. Bank Aceh, Medan Branch, undergoes the decrease in its clients’ loyalty which indicated by the increase in non-active clients in the period of 2011-2015. The objective of this research was to find out and analyze the influence of Service Quality on Clients’ satisfaction and its effect on their loyalty at PT. Bank Aceh, Medan Branch. The data were gathered by conducting descriptive quantitative survey and distributing questionnaires to 94 respondents and analyzed by using path analysis. The result of the research showed that,simultaneously, tangibles, reliability, responsiveness, assurance, and empathy had positive and significant influence on clients’ loyalty. Partially, tangibles had positive and significant influence on clients’ loyalty, reliability had positive and significant influence on clients’ loyalty, responsiveness had positive and significant influence on clients’ loyalty, assurance did not have any positive and significant influence on clients’ loyalty, and empathy had positive and significant influence on clients’ loyalty at PT. Bank Aceh, Medan Branch. Clients’ satisfaction had positive and significant influence on clients’ loyalty at PT. Bank Aceh, Medan Branch. Tangibles, reliability, responsiveness, assurance, and empathy directly and indirectly had positive influence on clients’ loyalty through clients’ satisfaction at PT. Bank Aceh, Medan Branch
Thermoelectric properties of undoped and doped (Ti0.75Sn0.25)O2

Thermoelectric properties of undoped and doped (Ti0.75Sn0.25)O2 were investigated for high-temperature thermoelectric conversion application. Nano-composites were formed by annealing above 1000°C. Outside the spinodal dome, ilmenite-type SnTiO3 precipitated from the rutile structure. Thermoelectric properties were measured in the temperature range from room temperature to 1000°C. (Ti0.75Sn0.25)O2 was doped with both acceptor and donor dopants. Both undoped and doped (Ti0.75Sn0.25)O2 exhibit n-type electrical behavior independent of the type of the dopant. The electrical conductivity was enhanced three orders of magnitude by donor doping with Nb2O5 or Ta2O5; achieving a maximum of 546 S/m at 850°C. The increase in electrical conductivity was accompanied by reduction of the absolute Seebeck coefficient. Seebeck coefficient reduction of −600 μV/K was observed between undoped and 4% Ta2O5 doped samples. The solid solution and doping reduced the thermal conductivity to <4 W/mK, far below the parent materials TiO2 and SnO2. Lattice thermal conductivity decreased with increasing temperature, achieving 1.9 W/mK at 900°C for 4% Ta2O5 doping. No further reduction in thermal conductivity was observed in annealed samples containing nano-sized SnTiO3 precipitates. Dimensionless figure of merit (ZT) attained was <0.1.
Cryo-TEM and SANS Microstructural Study of Pluronic Polymer Solutions

Cryogenic temperature transmission electron microscopy (cryo-TEM) and small-angle neutron scattering (SANS) were combined to give complete microstructural characterization of aqueous solutions of Pluronic F127, an (EO) 99 (PO) 65 (EO) 99 triblock copolymer. The images of vitrified specimens observed by cryo-TEM provided direct information about the building blocks of these systems, i.e., spheroidal micelles. This confirmed the structural model obtained from analysis of SANS data, which, in addition, provide quantitative information about the system. Occasionally spheroidal micelles were pressed closer to each other during specimen preparation, thus giving rise locally to higher concentration. The cubic phase that was thus formed was directly imaged. The existence of this lyotropic liquid crystalline phase was confirmed by SANS of an originally higher concentration solution. When exposed to shear, the polycrystalline phase transforms into a monodomain crystal with cubic symmetry. The system was also used to demonstrate the potential of selective electron beam radiolysis to enhance contrast in radiation-sensitive, inherently low-contrast systems.