Miracle-dz/UniFAR-FTUs huggingface dataset:
Interaction between uranium(VI) and siderite (FeCO3) surfaces in carbonate solutions

Abstract In order to assess the security of a long-term disposal of nuclear spent fuel, the prediction of radionuclide migration is needed. This paper presents the interaction between uranium(VI) and siderite surfaces, an iron carbonate present both in the near- and far-field of the storage, in carbonate solutions. The amount of uranium on the surface was determined after the interaction by alpha spectrometry. It appeared that the amount of uranium(VI) dropped with high pH and carbonate concentration, likely because of the predominance of UO2(CO3)22- and UO2(CO3)34- complexes in solution. The U4f X-ray photoelectron spectrum clearly highlighted that uranium present on the film has two different oxidation states and thus that uranium(VI) has been partially reduced by siderite.
Particle dispersion and turbulence modification in a dilute mist non-isothermal turbulent flow downstream of a sudden pipe expansion

Flow, particles dispersion and heat transfer of dilute gas-droplet turbulent flow downstream of a pipe sudden expansion have been numerically investigated for the conditions of heated dry wall. An Euler two-fluid model with additional turbulence transport equations for gas and particulate phases was employed in the study. Gas phase turbulence was modelled using the elliptic blending Reynolds stress model of Fadai-Ghotbi et al. (2008). Two-way coupling is achieved between the dispersed and carrier phases. The partial equations of Reynolds stresses and temperature fluctuations, and the turbulent heat flux equations in dispersed phase by Zaichik (1999) were applied. Fine droplets get readily entrained with the detached flow, spread throughout the whole pipe cross-section. On the contrary, large particles, due to their inertia, do not appear in the recirculation zone and are presented only in the shear layer region. The presence of fine dispersed droplets in the flow attenuates the gas phase turbulence of up 25 %. Heat transfer in the mist flow increased (more than twice in comparison with the single-phase air flow). Intensification of heat transfer is observed both in the recirculation zone and flow development region in the case of fine particles. Large particles enhanced heat transfer only in the reattachment zone. Comparison between simulated results and experimental data of Hishida et al. (1995) for mist turbulent separated flow behind a backward-facing step shows quite good agreement.
Receptor-based 3D QSAR studies on PPARγ agonists using CoMFA and CoMSIA approaches

Receptor-based (RB) quantitative structure-activity relationship (QSAR) studies were performed on the peroxisome proliferator-activated receptors gamma (PPAR γ ) agonists with antihyperglycemic property using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) implemented in the SYBYL packages. The initial X-ray structure of PPAR γ with GI262570 agonist was used to sketch 36 training set molecules having the receptor bound conformation. These structures were subjected to subset energy minimization using TRIPOS force field and aligned against an α-helix of PPAR γ receptor. Four models were generated using CoMFA and CoMSIA with two different grid spacing, 2 A and 1 A. After PLS analysis, the best predicted CoMSIA model with grid spacing 1 A, Model 4, showed that a leave-one out (LOO) cross validated value (r 2 c v ) and non-cross validated conventional value (r 2 n c v ) are 0.758 and 0.994, respectively. From the CoMFA and CoMSIA contour maps, important interactions crucial to strong binding to the receptor can be identified and verified. This information on the pharmacophore models can be used to design new ligands. Traditional ligand-based (LB) QSAR studies were also performed using the global minima of the same training set molecules. Compared to LB QSAR study, advantage of using subset-minimized RB QSAR study is discussed in detail.
Exams 2∗: EXposure analysis modeling system

EXAMS 2 was developed by Burns et al. for rapid evaluation of the behavior of organic chemicals in aquatic ecosystems. EXAMS 2 computes from the chemistry and the relevant transport and physicochemical properties of the compound and the ecosystem: Expected environmental concentrations. The fate of chemicals due to transport and transformation processes. The persistence of chemicals in the system once chemical loadings terminate. The program is interactive and allows the user to define and store the properties of the chemicals and environments. Loadings, transport, and transformations are combined into a set of differential equations assuming conservation of mass. Entering and leaving chemical mass into and from the environment is treated as the algebraic sum of external loadings, transport processes that export chemicals from the system, and transformation processes that convert chemicals to their transformation products. Water bodies can be combined via a set of several compartments or distinct zones of .
Application of Physical Chemistry in Product Development

theories are related to FORMULATION PARAMETERS. Designing a product on the basis of these principles aids the chemist in understanding the mechanisms involved, and enables him to modify and alter the physical features and chemical properties of the product to be marketed. The effects of ELECTROKINETIC PHENOMENA and of CRITICAL MICELLE CONCENTRATION on a variety of product types are discussed in a manner which provides guidance for future work. The physical-chemical principles of EMULSION formulation are discussed and related to emulsion separation, creaming, and graininess. Particle size, pigment wetting, particle-particle aggregation, and adhesion are related in a physical-chemical manner to typical COSMETIC PRODUCTS. Shelf-life determinations and performance characteristics are demonstrated to be associated with several of these principles.
Performance and Emission Characteristics of DME Engine with High Ratio of EGR

The combustion of dimethyl ether (DME) fuel, due to its simple chemical structure and high oxygen content, produces less exhaust gaseous products such as HC, CO and NOx. Moreover, soot-free combustion can be observed under all of the operating conditions, which allows a high ratio of exhaust gas recirculation (EGR) for NOx reduction without being restricted by the NOx-soot tradeoff. The effects of a high ratio of exhaust gas recirculation on performance and exhaust emissions from a DME engine were investigated. The results showed that EGR ratio has significant effects on power output and fuel consumption. NOx emission is considerably reduced with the decrease of oxygen concentration, and a higher level of EGR results in a greater reduction in NOx emission. Ultralow NOx emissions have been realized under a high ratio of EGR operations, however, accompanied with the increase of HC and CO emissions. High EGR ratios need to be applied under low loads, but low EGR ratios are sufficient for high loads. Consider.
On the lifetimes of Rydberg states probed by delayed pulsed field ionization

We present a simple model to evaluate the degree of l and ml mixing in high Rydberg states that results from perturbations caused by weak, homogeneous dc electric fields and static ions. This model predicts the lifetime of these states qualitatively and explains several seemingly contradictory observations obtained using zero‐kinetic‐energy (ZEKE) photoelectron spectroscopy. The presence of a small homogeneous dc electric field and a few ions in the sample volume causes ml mixing in general as well as l mixing, both of which contribute to the lengthening of the lifetimes. Consequently, the lifetime lengthening appears to be insensitive to the sample pressure. The effect of the dc electric field on the lifetime is complex. Although the electric field results in l mixing, with increasing field strength it inhibits ml mixing, and, at still higher field strength, induces ionization. The variation of the lifetimes with ion concentration is also complicated. At low ion concentration, the ml mixing varies across.
Hierarchical nanostructure of WO3 nanorods on TiO2 nanofibers and the enhanced visible light photocatalytic activity for degradation of organic pollutants

A hierarchically nanostructured TiO2/WO3 photocatalyst was synthesized via the subsequent hydrothermal treatment of electrospun TiO2 nanofibers in the presence of tungstic acid. With a uniform WO3 seed layer providing growth sites, the nucleation on the nanofibers was uniform, thus uniform WO3 nanorods could be grown. The samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence spectra (PL), and Brunauer–Emmett–Teller (BET) method. The results indicated that the WO3 nanorods with a diameter of about 40 nm and an average length of about 150 nm grew perpendicularly on the TiO2 nanofibers. The crystallite size and specific surface area of the bare TiO2 nanofibers were about 30 nm and 46.5 m2 g−1. The bare nanofibers are anatase phase with the average diameter of about 350 nm. The TiO2/WO3 heterostructures provide more accessible sites for both catalysis and adsorption, and the WO3 nanorods possess a single crystal structure, which facilitates the migration of the photogenerated electrons. Photocatalytic tests show that the TiO2/WO3 heterostructures exhibit a remarkably higher degradation rate of organic pollutants than that of the bare TiO2 nanofibers under visible light irradiation. The enhanced photocatalytic activity is attributed to the extended absorption in the visible light region and the effective charge separation derived from the coupling effect of TiO2 and WO3 nanocomposites.
Preparation and properties of isobutylene-isoprene rubber-clay nanocomposites

Isobutylene isoprene rubber (IIR)-clay nanocomposites have been prepared successfully by melt intercalation with maleic anhydride-grafted IIR (Ma-g-IIR) and organophilic clay. In IIR-clay nanocomposites, the silicate layers of the clay were exfoliated and dispersed into the monolayer. The nanocomposites exhibited greater gas barrier properties compared with those of Ma-g-IIR. When 15 phr clay was added, gas barrier properties were 2.5 times greater than those of Ma-g-IIR. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1182–1188, 2006
Participation of hydrogen peroxide in halogen activation in the low stratosphere

Measurements of hydrogen peroxide conversion into Caro's acid in sulphuric acid at T ≈ 298 K and H2SO4 content 78/95 wt% were performed to monitor the equilibriums: H2O2 + H3O+ ↔ H3O2 + + H2O and H2O2 + HSO4 − ↔ HSO5 − + H2O yielded K(298) = 8 × 10−4 and K(298) = 1.2 × 10−2, respectively. The physical solubility of H2O2 as well as that including H3O2 + and HSO5 − has been estimated. The calculation of the Henry's law coefficient (T = 298) of H2O2 shows the typical salting-out effect, while for the case of H3O2(aq) + and HSO5(aq) − this coefficient exhibits a sharp rising with H2SO4 content, starting from almost 50 wt%. An increase in the oxidative power of H2O2, H3O2(aq) + and HSO5(aq) − is observed, as H2SO4 concentration increases. In addition, the kinetics of the liquid-phase reactions involving these reagents are analysed on the basis of a correlation between the rate constants and the thermodynamic data. Finally, the occurrence of sulphate aerosol reactions involving the components that affect halogen activation in the low stratosphere is discussed.
Visuomotor brain network activation and functional connectivity among individuals with autism spectrum disorder

Sensorimotor abnormalities are common in autism spectrum disorder (ASD) and predictive of functional outcomes, though their neural underpinnings remain poorly understood. Using functional magnetic resonance imaging, we examined both brain activation and functional connectivity during visuomotor behavior in 27 individuals with ASD and 30 typically developing (TD) controls (ages 9–35 years). Participants maintained a constant grip force while receiving visual feedback at three different visual gain levels. Relative to controls, ASD participants showed increased force variability, especially at high gain, and reduced entropy. Brain activation was greater in individuals with ASD than controls in supplementary motor area, bilateral superior parietal lobules, and contralateral middle frontal gyrus at high gain. During motor action, functional connectivity was reduced between parietal‐premotor and parietal‐putamen in individuals with ASD compared to controls. Individuals with ASD also showed greater age‐associated increases in functional connectivity between cerebellum and visual, motor, and prefrontal cortical areas relative to controls. These results indicate that visuomotor deficits in ASD are associated with atypical activation and functional connectivity of posterior parietal, premotor, and striatal circuits involved in translating sensory feedback information into precision motor behaviors, and that functional connectivity of cerebellar–cortical sensorimotor and nonsensorimotor networks show delayed maturation.
Polyaniline–RuO2 composite for high performance supercapacitors: chemical synthesis and properties

Composite thin films of polyaniline–ruthenium oxide (PANI–RuO2) are prepared by a chemical bath deposition (CBD) method. The prepared thin films are characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and FT-Raman spectroscopy. XRD patterns reveal the amorphous nature of the composite thin films. FT-IR and FT-Raman spectroscopy confirm PANI–RuO2 composite formation. Cyclic voltammetry, galvanostatic charge–discharge and impedance analysis are carried out in order to investigate the applicability of the composite electrode as a supercapacitor. The PANI–RuO2 composite electrode demonstrate the maximum specific capacitance of 830 F g−1. The specific energy and specific power of the PANI–RuO2 composite electrode are 216 W h kg−1 and 4.16 kW kg−1, respectively. The observed specific capacitance is the best yet reported for a PANI–RuO2 composite supercapacitor in H2SO4 electrolyte. Moreover, the composite electrode shows enhanced cycling stability. These results demonstrate the potential of developing the PANI–RuO2 composite electrode material for high-performance supercapacitors.
Vibrational Spectra and Molecular Structure of Ethyl Methyl Sulfide

The Raman spectra of the liquid, unannealed solid and annealed solid, and the infrared spectra of the gas, liquid, and annealed solid of ethyl methyl sulfide were measured. Normal vibrations were treated of the trans and gauche isomers. C–S stretching, CH2 rocking and skeletal deformation vibrations were discussed in relation with molecular structures. Only the gauche isomer was found to exist in the annealed solid. In the liquid state, the gauche isomer was found to be more stable, by 0.14±0.05 kcal/mol, than the trans isomer. The vibrational assignment made of ethyl methyl sulfide is consistent with those of related sulfides and disulfides.
Toxicity of Copper in the Presence of Organic Substances in Sewage Sludge

The toxicity of Cu to Photobacterium phosphoreum was studied in the presence of both model substances and organic substances that have been identified as sludge components. Copper toxicity increased in the presence of LAS, caffeine, myristic acid, palmitic acid, nonylphenol, ethyl xanthogenate and oxine, with a steep toxicity gradient for the latter two compounds. Other substances, including complexing agents, ameliorated Cu toxicity. Synergistic/antagonistic effects of organics and Cu in sludge were tested through comparison of the toxicity of Cu added to three sludge types with the concentration of electrochemically available Cu at different sludge/Cu proportions. The toxicity of Cu in raw and digested sludge was much higher than could be explained by the concentration of electrochemically available Cu alone and was attributed to synergism and potentially the formation of lipid-soluble Cu complexes.
Chemically and geometrically enhanced focused ion beam micromachining

Improvements in focused ion beam (FIB) material removal rates utilizing geometric and chemical enhancement were investigated. Geometrical optimization of FIB micromachining of Permalloy and diamond was investigated to determine the magnitude of material removal rate gains that could be attained by increasing the angle of the ion beam with respect to the sample surface normal. The combination of geometrical optimization with chemical enhancement (C2Cl4 for Permalloy and H2O and XeF2 for diamond) was then investigated to determine whether additional gains in material removal rate could be attained. FIB sharpening of a diamond nanoindenter tip is also presented as a practical example of diamond micromachining with H2O as the removal rate enhancing species.Improvements in focused ion beam (FIB) material removal rates utilizing geometric and chemical enhancement were investigated. Geometrical optimization of FIB micromachining of Permalloy and diamond was investigated to determine the magnitude of material removal rate gains that could be attained by increasing the angle of the ion beam with respect to the sample surface normal. The combination of geometrical optimization with chemical enhancement (C2Cl4 for Permalloy and H2O and XeF2 for diamond) was then investigated to determine whether additional gains in material removal rate could be attained. FIB sharpening of a diamond nanoindenter tip is also presented as a practical example of diamond micromachining with H2O as the removal rate enhancing species.
A quantum chemical comparative study of Epinine and Hordenine

Epinine, is an organic compound and natural product that is structurally related to the important neurotransmitters dopamine and epinephrine while Hordenine, is an alkaloid of the phenethylamine class that occurs naturally in a variety of plants. These have nearly similar type of structures so we have done a comparative study of epinine and hordenine with B3LYP with 6-311 G (d, p) as the basis set. Here we have done a relative study of their structures, vibrational assignments, thermal and electronic properties of epinine and hordenine. We have plotted frontier orbital HOMO- LUMO surfaces, Molecular electrostatic potential surfaces to explain the reactive nature of epinine and hordenine.
Ocorrência de corpos silicosos em horizontes superficiais de solos de diferentes ecossistemas

O entendimento dos processos que causam as diferentes distribuicoes de corpos silicosos no solo e essencial para a interpretacao dos possiveis fatores ambientais responsaveis pela estabilidade deles, deposicao de sedimentos, formacao de paleossolos e para analise de sitios arqueologicos. Assim, a presente pesquisa objetivou identificar a ocorrencia de corpos silicosos encontrados em horizontes superficiais de solos oriundos de diferentes ecossistemas terrestres. Amostras de horizonte superficial de 10 perfis de solo foram coletadas e queimadas em mufla, para remocao da materia orgânica. Posteriormente, as amostras foram tratadas com HCl 10 cL L-1, para remocao das impurezas contidas na cinza. A fracao silte foi obtida por sedimentacao, usando o procedimento de analise granulometrica. A maior parte dos corpos silicosos em solos encontra-se na fracao silte. Dessa fracao, montaram-se lâminas, utilizando oleo de imersao tipo A para identificacao dos corpos silicosos em microscopio optico. A analise dos resultados permitiu observar a variedade de formas e abundância de corpos silicosos nos solos estudados, sendo mais abundantes e diversificados no solo desenvolvido de quartzito. Nos Latossolos, nao houve diferenca em abundância de fitolitos em relacao aos solos dos biomas do Cerrado, Mata Atlântica e Caatinga.
Night-Time Ground Hyperspectral Imaging for Urban-Scale Remote Sensing of Ambient PM. I. Aerosol Optical Thickness Acquisition

Aerosol loadings in vertical atmospheric columns are commonly measured by satellite-borne or ground instruments that remotely sense the spectral extinction through the optical path. However, correlations of these integrated measurements with ground-level particulate matter concentrations are highly influenced by local meteorology, seasonality, and the surface albedo. Moreover, as most measurements are based on solar radiation, they are limited to daytime. To account for these limitations, we study the feasibility of using a ground hyperspectral camera for acquiring images of artificial light sources through horizontal urban-scale open paths during the night, in order to retrieve the apparent spectral aerosol optical thickness. Laboratory-scale measurements demonstrated a linear response of the camera and set the spectral operational range. A procedure for night-time imaging of illuminating targets through ambient open paths has been developed to enable a consistent selection of pixels for analysis, providing measurable apparent aerosol optical thickness. We demonstrate the validity of this procedure by field acquisition of hyperspectral signatures through different arid and rural open paths in the Negev desert, Israel. An open path of 180 m provided a test case for imaging during clear and stable ambient conditions, from which an inherent measurement error of ∼4% was estimated. Imaging through a very long open path indicated an uppermost open path limit of about 4 km, resulting from a significant attenuation of the sensor's spectral response. Imaging and aerosol optical thickness retrieval under common environmental conditions through urban-scale open paths of about 1 km in Haifa is also demonstrated. Copyright 2012 American Association for Aerosol Research
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Piedras Blancas National Park, in southern Costa Rica, is an important component of two biological corridors connecting the Osa Peninsula (Corcovado National Park) and La Amistad International Park. Understanding the mammal community composition of Piedras Blancas will provide baseline data to evaluate the success of conservation efforts. We used camera traps and opportunistic observations to describe the medium-sized and large mammals of the park. We deployed camera traps for 1,440 trap nights (2016-2018). We detected 19 mammal species from seven orders and 13 families. Five species are globally threatened: Leopardus wiedii (Schinz, 1821), Saimiri oerstedii (Linnaeus, 1758), Ateles geoffroyi (Kuhl, 1820), Alouatta palliata (Gray, 1849), and Tapirus bairdii (Gill, 1865). We did not detect two locally threatened species, Panthera onca (Linnaeus, 1758) and Tayassu pecari (Link, 1795). Our research highlights a need for critical conservation work within the proposed biological corridor to support Costa Rica’s most threatened wildlife.
Photochemical reduction of nitrate to nitrite in aqueous solution and its application to the determination of total nitrogen in water

An equilibrium between nitrate and nitrite exists under UV irradiation, and in alkaline solution nitrate can be 93% reduced to nitrite within 8 min. This property has been applied to the determination of total nitrogen in environmental water samples. The coefficient of variation is 1.94% for river waters with a total nitrogen concentration of 1.80 mg l–1. A total nitrogen determination can be completed within 1 h by this manual procedure. A modification to the colour development for nitrite determination was made, which was used when the nitrite concentration was higher than 0.3 mg l–1.