Miracle-dz/UniFAR-FTUs huggingface dataset:
Use of a mixed-Weibull distribution for the identification of PD phenomena [rotating machines]

The interaction between partial discharge (PD) phenomena occurring in insulating systems is investigated in this paper. In particular, the recognition of two PD phenomena simultaneously active is approached by means of a five-parameter additive Weibull distribution. Various shapes of the PD height distribution, obtained from measurements performed on specimens of stator bars and windings of ac rotating machines, are considered. It is shown that the proposed probability function fits well the partial discharge height distributions. The probability distribution relevant to each concurring PD phenomenon can be derived, analysed and identified. Moreover, the standard average quantities are estimated for each phenomenon. >
Precise and accurate isotopic analysis of microscopic uranium-oxide grains using LA-MC-ICP-MS

Uranium isotope (235U, 236U, 238U) ratios were determined for microscopic uranium-oxide grains using laser-ablation multi-collector inductively-coupled-plasma mass-spectrometry (LA-MC-ICP-MS). The grains were retrieved from contaminated soil and dust samples. The analytical technique utilised is rapid, requires minimal sample preparation, and is well suited for nuclear forensic applications. Precision and accuracy were assessed by replicate analyses of natural uraninite grains: relative uncertainty for 235U/238U is 0.2% (2σ), and the mean is in agreement with the natural ratio. A total of 115 uranium-oxide grains were analysed from environmental samples (soils and dusts); all of these were depleted uranium (DU) from a factory that produced uranium articles. Knowledge of the range of isotope ratios from particles of this controversial contaminant has proven useful when interpreting isotope ratios from bulk samples. Variation of the measured isotope signatures reveals details of the history of uranium processing and emissions.
Finite-Size Networks from Cylindrical Polyelectrolyte Brushes and Porphyrins

We report on the electrostatic self-assembly of negatively charged cylindrical polystyrenesulfonate (NaPSS) brushes and stiff organic counterions of different valency. In particular, the tetravalent cationic porphyrin meso-tetrakis(4-(trimethylammonium)phenyl)porphyrin (TAPP) yielded two new supramolecular architectures that are stable in aqueous solution. The porphyrin binds to the polyelectrolyte brush due to electrostatic and secondary π−π interactions and can further interconnect the brushes to nanoscale networks. In salt solution individual porphyrin-decorated cylindrical brushes were obtained. Structures formed are characterized by UV−vis spectroscopy, atomic force microscopy (AFM), cryo-transmission electron microscopy (cryo-TEM), small-angle neutron scattering (SANS), and dynamic light scattering (DLS). In order to study porphyrin aggregates by DLS, an IR laser setup (λ = 831.5 nm) was used. The new morphologies have potential as functional structures in molecular electronics and pharmaceutics.
Assessment of DNA Damage after Photodynamic Therapy Using a Metallophthalocyanine Photosensitizer

Photodynamic therapy (PDT) is a chemotherapeutic approach that utilizes a bifunctional reagent, a photosensitizer (PS) that localizes to the target tissue relative to the surrounding tissue and is toxic when exposed to laser light. PDT rapidly induces cell death, inflammatory and immune reactions, and damage of the microvasculature. DNA damage results from a variety of factors including UV-light, X-rays, ionizing radiation, toxins, chemicals, or reactive oxygen species. The aim of this study was to determine the effect of PDT as well as the influence of presensitization leading to the adaptive response (AR) on the integrity of DNA. Lung (A549), breast (MCF-7), and esophageal (SNO) cancer cells and Zn sulfophthalocyanine as PS with irradiation conditions of 10 J/cm2 at 636 nm were used. Subcellular localization of PS, cell morphology, and viability after PDT and DNA damage were determined. A significant decrease in viability and marked DNA damage was observed in all 3 cancer cell types in response to PDT while the adaptive response was demonstrated to significantly decrease the effectiveness of the PDT.
Density Functional Study of NO Desorption from Oxidation of Nitrogen Containing Char by O2

Mechanisms for NO desorption during reactions between O2 and nitrogen-containing char have been studied using density functional theory at the B3LYP/6-31G(d) level. The chemisorption of O2 on char surface was found to be barrierless and 440 kJ mol−1 exothermic. A number of reaction pathways with barriers below 440 kJ mol−1 were characterized. The chemisorption product could proceed directly to NO desorption with an energy barrier of 419 kJ mol−1 or undergo a series of rearrangement reactions to release NO, in which the highest energy barrier was 360 kJ mol−1. An oxygen atom could migrate along the edge of char if an adjacent active site was vacant. The overall migration reaction was 107 kJ mol−1 exothermic. Transition state theory was used to calculate forward and reverse rate constants of intermediate reactions in the range of 1000–1800 K and two-parameter Arrhenius expressions were fitted. NO formation from nitrogen-containing char heterogeneous oxidation was dominated by indirect pathway consisting of a series of rearrangement reactions.
Birefringence and Refractive Indices Dispersion of Different Liquid Crystalline Structures

Abstract The birefringence and refractive indices of several liquid crystalline structures were measured throughout the visible wavelength region (400–900 nm) at different temperatures. Mixtures composed of members of the same homologous series were used in order to achieve the nematic phase at room temperature. Data on 28 mixtures, mainly with cyclohexane - phenyl and biphenyl cores, are presented. The set includes widely used structures as well as newly synthesized. Some details of experimental methods, formulas for interpolation of the results and observed regularities are briefly discussed.
Two stage flotation of sodium feldspar – from laboratory to industrial application

Abstract In this study, results are presented of laboratory flotation tests and industrial application to separate colouring minerals (muscovite, biotite, rutile, sphene), some iron oxides and clays from Çine-Ceyhan sodium feldspar ore owned by Kalemaden A.S. In the first stage, conventional mica flotation was carried out at pH 2·5–3 by using tallow amine acetate as collector together with a frother mixture of 50% MIBC and 50% pine oil. Following mica flotation, in the second stage, the effect of sodium oleate, pH and the fineness of grind were tested. Experimental studies indicated that the ore should be ground to –300 μm and clayey slimes (–25μm) washed out prior to flotation so as to separate colouring gangue minerals effectively. Under optimum conditions, a high quality concentrate containing 0.1% TiO2 + Fe2O3 and giving very glossy white firing test button at 1260°C was obtained by two stage flotation at pH 2·5–3 with 225 g/t Armac TD for micas and at pH 5·5–6·5 with 2000 g/t Na-oleate for titanium and iron oxides. Based on the extensive experimental data, a flotation plant was designed, built and started up in November 1999.
Surface Oxidation Kinetics of GaAs Oxide Growth by Liquid Phase Chemical-Enhanced Technique

The initial stage of GaAs oxidation by a near-room-temperature liquid phase chemical-enhanced technique has been studied. Based on the experimental results of X-ray photoelectron spectroscopy, a complete model illustrating the chemical composition of the grown oxide film has been established. To clarify the kinetics of oxide growth in a liquid solution in more detail, we have also performed selective oxidation and surface profile measurements. Unusual features of the oxide growth kinetics have been observed by investigating the physical structure of oxide at the edge of mask in the selective oxidation.
Cluster Analysis of Gallstone FT-IR Spectra: Tests on Simulated Mixture Spectra and Comparison between Spectral and Morphological Classification of Human Gallstones

Sixty-four combination spectra of three major gallstone components [i.e., cholesterol, calcium bilirubinate, and calcium carbonate (aragonite)] were simulated in accordance with a “fractal” ternary diagram. Comparison between the original pattern of composition and factorial maps of pretreated spectra makes it possible to show the effects of different normalization procedures (Euclidean norm, spectrum maximum, and area under spectrum set to 1). Cluster analysis of these spectra, depending on different agglomerative links (single linkage, complete linkage, average linkage, and Ward's criterion), was carried out. All the resultant trees yield the same groups, but Ward's criterion best preserves the pattern of the data. More than 100 gallstones from France and Vietnam were classified by using cluster analysis of their FT-IR spectra with Ward's criterion. Seven homogeneous groups of spectra were extracted, which have been significantly correlated to the four morphological types of gallstones: pure cholesterol, mixed cholesterol, brown pigment, and black pigment stones. This analysis also reveals that the morphological groups are not homogeneous in composition, in particular for black pigment stones.
Crescimento e produtividade da mamoneira irrigada com diferentes diluições de esgoto doméstico tratado

The effects of the irrigation with domestic wastewater effluent on the growth variables and the productivity of castor bean, genotyps EBDA MPB 01, were evaluated under field conditions. The research was carried out from December 2009 to June 2010, at UFRB experimental area, in Cruz das Almas, BA. Four different proportions of dilution of domestic wastewater effluent in comparison with the conventional treatment were studied, in the following way: T1 - 100% of the treated effluent; T2 - 75% of the effluent +25% of artesian well water; T3 - 50% of the efluent +50% of artesian well water; T4 - 25% of the effluent +75% of artesian well water; T5 - conventional treatment (chemical fertilization and supplementary irrigation with water of artesian well). A randomized block design was used with four replications, totaling 20 experimental units. The productivity of the castor been did not show statistical differences among the treatments. The use of wastewater in castor been crop did not affect the growth variables analyzed.
Effects of Potassium Rates and Sources on Fiber Quality Parameters in Four Cultivars of Cotton Grown in Aridisols

Abstract A field experiment was conducted using four cotton (Gossypium hirsutum L.) cultivars: CIM-448, CIM-1100, NIAB-Karishma, and S-12 supplied with four rates of potassium fertilizer (0, 62.5, 125.0, 250.0 kg K ha−1) and two sources of potassium fertilizer (K2SO4, KCl) to determine the effect of potassium fertilizer on fiber quality. Result showed that fiber quality parameters differed significantly in response to various potassium fertilizer levels and sources in different cultivars. Fiber length, fiber fineness, fiber strength, and fiber maturity ratio increased due to addition of potassium fertilizer. Sulphate of potash had an edge over muriate of potash in improving fiber quality parameters. Each of fiber quality parameters was positively correlated to potassium concentration in fiber tissues at maturity, potassium concentration in leaf tissues at bloom stage and ammonium acetate extracted- potassium in the soil. These investigations indicate that adequate potassium supply to developing fruit was an important determinant of lint parameters to produce quality cotton.
Efficient synthesis of glycerol carbonate/glycidol using 1,8-diazabicyclo [5.4.0] undec-7-ene (DBU) based ionic liquids as catalyst

Transesterification of dimethyl carbonate with glycerol to glycerol carbonate has been catalyzed efficiently using basic ionic liquids as catalysts. Activity of all the ILs tested is very high and the best result (96% conversion with 82% selectivity to glycerol carbonate and 18% selectivity to glycidol) was obtained using IL1 as catalyst. The effect of catalyst loading has significant influence on the selectivity pattern. The higher activity of the ionic liquid is explained with a plausible mechanism based on the co-operative effect of both cation and anion.
Corrosion Inhibition and Adsorption Properties of Ethanol Extract of Vernonia Amygdalina for the Corrosion of Mild Steel in H2SO4

Inhibitive and adsorption properties of ethanol extract of vernonia amygdalina for the corrosion of mild steel were studied using weight loss, thermometric, gasometric and IR methods of monitoring corrosion. The results revealed that ethanol extract of Vernonia amygdalina inhibited the corrosion of mild steel. The inhibition efficiency of the extract increased as the concentration of the extract increases. The inhibitor was found to function by being adsorbed on the surface of mild steel. The adsorption of the inhibitor followed the Langmuir adsorption isotherm. IR spectra of the corrosion product (without inhibitor), the extract and the corrosion product (with the inhibitor) confirmed that ethanol extract of vernonia amygdalina is an adsorption inhibitor. Phytochemical studies also revealed that ethanol vernonia amygdalina contains tannin, saponnins, flavanoid and anthraquinone, all of them contributing to the corrosion inhibition. Physical adsorption mechanism has been proposed from the values of some of the thermodynamic parameters obtained.
Ammonia Emissions from a Commercial Broiler House

Emission of ammonia gas from broiler houses has become an issue of concern. Yet most of the research that has been done on ammonia in poultry houses is more concerned with in-house air quality than with emissions, and most of the research has occurred in northern Europe where climatic conditions and perhaps management are different from that in the southeastern United States which is the area that produces the largest amount of poultry in the US. This research monitored ventilation rates and ammonia levels in a commercial broiler house in the southeastern United States to determine the approximate emission rates under hot and cool climatic conditions. In hot conditions, although ammonia concentrations were only in the 3 to 5 ppm range, extremely high ventilation rates resulted in estimated emissions of approximately 35 lb (16 kg) /day/house on some days. The instrument used to measure ammonia levels was not reliably accurate at concentrations below 5 ppm, however, and an error of 1 ppm at these high ventilation rates would result in an error of 20 lb (9 kg)/day/house. In cooler conditions, ammonia concentrations were higher, and ventilation rates were lower resulting in daily emissions similar to summer conditions. However, when the sensor was exposed to constant high levels of ammonia, the output became unstable, rendering these results questionable as well.
Structure and thermodynamics of the liquid–vapor interface

This paper is concerned with the effects that density fluctuations in different regions of a liquid–vapor interface have on the interfacial thermodynamic and structural properties. The total volume V is divided into a square array of columns whose width is the order of the bulk correlation length. The canonical partition function is written as a sum of constrained partition functions, each describing a system with a given number of particles in each column. Changes in the occupation number of each column (i.e., density fluctuations) are related to changes in position of the local Gibbs dividing surface, and the free energy of such distortions of the Gibbs surface is estimated using macroscopic ideas similar to those used in the capillary wave theory by Buff, Lovett, and Stillinger. Corrections to the interface tension as calculated for a single column with periodic boundary conditions are given. We make a self‐consistent choice of the column width which yields a scaling law originally porposed by Widom. F.
Effect of chemical reaction mechanisms and NOx modeling on air-fired and oxy-fuel combustion of lignite in a 100-kW furnace

In the present paper, a three-dimensional numerical investigation of pulverized dry lignite was undertaken, integrating the combustion of four different scenarios adopted experimentally in a 100-kW Chalmers laboratory-scale furnace. A hybrid unstructured grid computational fluid dynamics (CFD) code was used to model and analyze: an air-fired, oxy-fuel OF25 (25 vol % O2 concentration), oxy-fuel OF27 (27 vol % O2 concentration), and oxy-fuel OF29 (29 vol % O2 concentration). The appropriate mathematical models with the related kinetics parameters were implemented to calculate the temperature distributions, species concentrations (O2, CO2, CO, H2O, and H2), NOx emission concentrations, and the radiation heat transfer. The multistep chemical reaction mechanisms were conducted on the gas phase and solid phase of coal reaction in one-, two-, and three-step reaction schemes. The predicted results showed reasonably good agreement against the measured data for all combustion cases; however, in the three-step schem.
Carbonatobis(1,10‐phenanthroline)cobalt(III) perchlorate

[Co(CO 3 )(C 12 H 8 N 2 ) 2 ](ClO 4 ) cristallise dans P2 1 /n avec a = 11,732, b = 12,404 et c = 16,194 A, β = 108,80 °, Z = 4; affinement jusqu'a R = 0,063. Le cation a une symetrie d'ordre 2 typiquement non cristallographique et l'environnement de Co est approximativement un octaedre cis.
Organic and inorganic selenium speciation in urine by on-line vesicle mediated high-performance liquid chromotography–focused microwave digestion–hydride generation–inductively coupled plasma mass spectrometry

A vesicle mediated high performance liquid chromatographic (HPLC)–microwave digestion (MW)–hydride generation (HG) system coupled on-line with atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS) has been assessed for selenium species separation and detection. Selenocystine, selenomethionine, selenoethionine, selenourea, SeIV and SeVI are separated by vesicle mediated chromatography prior to on-line selenocompounds microwave digestion with a KBrO3–HBr mixture to generate SeIV continuously, which is finally transformed into SeH2, in a continuous manner with a merging flow of sodium tetrahydroborate(III). Analytical characteristics of this coupling are compared with those obtained coupling HPLC–ICP-MS via conventional nebulisation. Detection limits (DLs) obtained for selenocystine, selenomethionine, selenoethionine, selenite and selenate in spiked human urine, when ICP-MS was used as detector, ranged between 1.0 and 5.3 µg l–1 (51–267 pg), while precision ranged between±3.4 and±8.4%. This continuous system, vesicle mediated HPLC–MW–HG–atomic detection, allows the separation and detection of selenocystine, selenourea, selenomethionine, selenoethionine, selenite and selenate in human urine. The analytical versatility of such coupling (with ICP-MS as the atomic detector) allows basal selenium speciation in urine. Three different normally occurring selenium species in human urine, simply diluted (1+1), have been found. The relative sophistication of the vesicle mediated–HPLC–MW–HG–ICP-MS interface, versus HPLC–ICP-MS via conventional nebulisation, can be justified because of its considerably higher sensitivity for most of the selenocompounds assayed, lower matrix interferences and the possibility of simultaneous interference free 77Se and 78Se monitoring.
HPLC enantioseparation on cellulose tris(3,5‐dimethylphenylcarbamate) as a chiral stationary phase: Influences of pore size of silica gel, coating amount, coating solvent, and column temperature on chiral discrimination

Cellulose tris(3,5-dimethylphenylcarbamate) (CDMPC) was coated on large-pore silica gels and used as a chiral stationary phase (CSP) for high-performance liquid chromatographic separation of enantiomers. The influences of pore size of silica gel, coating amount of CDMPC, coating solvent, and column temperature on chiral discrimination were investigated. CSPs prepared with a large-pore silica gel having a small surface area showed higher chiral recognition. The amount of CDMPC adsorbed on the silica gel influenced the chiral recognition of some racemates. Loading capacity of racemates increased with an increase of the amount of CDMPC supported on the silica gel, and a CSP coated with 45% CDMPC by weight can be used for both analytical and semi-preparative scale separations. The CDMPC, coated using acetone as the coating solvent, exhibited, in many cases, higher enantioselectivity than that obtained with tetrahydrofuran F as the coating solvent. © 1996 Wiley-Liss, Inc.
Concentration-dependent magnetic hyperthermic response of manganese ferrite-loaded ultrasmall graphene oxide nanocomposites

Water soluble and biocompatible ∼18 nm manganese-doped ferrite (MnxFe1−x)Fe2O4 decorated ultrasmall graphene oxide (GO) nanocomposites were synthesized. Ultrasmall nanocomposites were fabricated with a hydrodynamic size of 50.6 ± 0.3 nm, approximately ∼80 nm lateral dimension and ∼20 nm thickness (from AFM analysis), indicating a sheet-like structure with only a few nanoparticles attached. The concentration-dependent magnetic hyperthermic response of such nanocomposites under an alternating magnetic field (AMF) and very dilute conditions (<0.3 mg mL−1) was also investigated. The field-dependent specific absorption rate (SAR) values of the nanocomposites were found to have increased by approximately two-fold when their concentration was reduced by a factor of 3. Such nanocomposites also exhibited excellent colloidal stability as well as suitable biocompatibility (up to 2 mM iron concentration) with NIH/3T3 fibroblast cells.
Dielectric spectroscopy study of barium titanate ceramics doped with europium ions

The differences between the physical properties of BaTiO3 and BaTiO3+0.1wt. % Eu2O3 were identified. Scanning electron microscopy studies show that the small addition of europium to barium titanate ceramics results in a decrease in the average grain size from 5–10 μm to 2–4 μm. The alternating current measurements were performed in the temperature range from 150 to 600 K and in the frequency range from 0.1 Hz to 10 MHz. Both thermal analysis and dielectric spectroscopy indicate that the temperature of the ferroelectric–paraelectric phase transition shifts towards room temperature.
Effects of Mixing State on Black Carbon Measurements by Laser-Induced Incandescence

Laboratory experiments and theoretical calculations were made to characterize the performance of a Single Particle Soot Photometer (SP2) manufactured by Droplet Measurement Technologies (DMT), which was designed to measure the mass and the mixing state of individual black carbon (BC) or elemental carbon (EC) particles, based on the laser-induced incandescence (LII) technique. In this study, graphite was used as a surrogate of EC. Graphite particles with mass equivalent diameters of 110–200 nm were layered with organic liquids (glycerol and oleic acid) to produce coated graphite with diameters up to 650–800 nm. These were sampled by the SP2 to measure the waveforms (i.e., time development) of the LII and scattering signals. The peak temperature and the peak LII signal of graphite particles were independent of the coating thickness or the coating material to within experimental errors. These results indicate that the mass of EC can be measured by using peak LII signal without interference by the coating conditions. It was also shown that the difference between the times of the scattering and LII peaks can be used as an indicator of coating on EC with thicknesses larger than about 100–200 nm. LII and scattering waveforms were calculated using a newly developed theoretical model that takes into account the physical processes controlling the temperature and evaporation rate of the coated graphite particle in the laser beam. The calculations reproduced the general features of observed waveforms of LII and scattering signals, providing a firm theoretical basis for the interpretation of the SP2 data.