Miracle-dz/UniFAR-FTUs huggingface dataset:
Adsorption of Polyampholytes to Charged Surfaces

The adsorption of flexible polyampholytes to charged surfaces has been investigated. The electrostatic interactions are included in a mean-field manner, while the chain connectivity is treated by Metropolis Monte Carlo (MC) simulations. For large enough surface charge densities, adsorption is found both for neutral polyampholytes and for polyampholytes carrying the same net charge as the surfaces. The simulation results are used to check the reliability of previously proposed analytical theories. The exponents predicted in those scaling relations are not reproduced by MC simulations. The simulations show that the size of the adsorbed polyampholyte initially grows with increasing surface charge density, but for sufficiently charged surfaces it reaches a maximum and starts to decrease. This general behavior is qualitatively captured by scaling arguments. The MC simulations do not bear any evidence for the existence of three disparate regimes where the polyampholyte adsorbs in different conformations.
Dissociative photoionization of H2 and D2 in the energy region of 25–45 eV

Dissociative photoionization of molecular hydrogen and deuterium has been studied using synchrotron radiation and an electrostatic analyzer with a position sensitive detection system for the threshold region of the doubly excited states, 25–45 eV. The Q1 1Σ+u(1) autoionizing state plays an important role in the production of fast protons below 30 eV. It is found that, for the incident photon energy 30–40 eV, the dominant process for the production of energetic protons is autoionization of the Q2 1Πu(1) state which preferentially autoionizes to the H+22pσu state rather than to the H+21sσg state. The Q2 1Πu(2) and Q2 1Σ+u autoionizing states are also found to produce fast protons in this energy region. Above 42 eV, the kinetic energy distributions are dominated by direct ionization to the 2pσu and 2pπu states of H+2.
The Influence of Graphene Sheet on the Dynamics of Cholesterol Molecules in the Lodgment Located near a Transmembrane Protein – MD Study

Molecular dynamics (MD) simulations have been made for a cluster of cholesterols localized near the transmembrane protein at the physiological temperature of 310 K. It was observed that the cholesterol molecules form a lodgment on the surface of protein. Additional studies were made of the influence of graphene sheet on several physical observables of cholesterol molecules including: the radial distribution function, the mean square displacement, diffusion coefficient and the linear and angular velocity autocorrelation functions.
Chlorophyll fluorescence as a measure of photosynthetic carbon assimilation

It has long been supposed that there must be an inverse relation between chlorophyll fluorescence and photosynthetic carbon assimilation. Excitation of chlorophyll, by light, initiates the electron transport that drives photosynthesis. Excess excitation energy is dissipated as heat and as light (fluorescence) but, at least in regard to carbon assimilation, the actual fluorescence signal was once regarded as too complex to permit interpretation. More recently, the concept of two major fluorescence-quenching mechanisms and the development of techniques and devices that allow these to be resolved, has advanced understanding. Concepts and procedures based on linear relations between fluorescence parameters and carbon assimilation have allowed good predictions of photosynthetic rates. Here we show that a single curvilinear relation can be derived for several disparate plant species and suggest that this could allow photosynthesis and the effect of light on ‘dark respiration’ to be measured by non-intrusive fluorescence techniques without recourse to analysis of gaseous exchange between leaf and atmosphere.
Numerical simulation of forced convective evaporation in thermal desalination units with vertical tubes

Abstract The subject of present study is a numerical simulation of transient solution of evaporation on upward flow in a two-dimensional vertical tubes by using the water as the working fluid. The heat transfer mechanisms are energy and mass transfer during the phase change based on volume of fluid model in commercial CFD software, with a user defined function. Operating conditions are specified in saturation temperature of water flow boiling. The physical properties of water are determined using inlet temperature and pressure system in saturation conditions. The characteristic of water flow boiling such as void fraction, heat transfer coefficient, and wall temperature distribution are investigated in the range of various heat fluxes. Due to agitation of vapor bubbles, the flow is turbulent which is simulated based on SST K–ω model and also the pressure implicit with splitting of operators pressure–velocity coupling scheme is used to improve the efficiency of calculation.
Sequential surface chemical reaction limited growth of high quality Al2O3 dielectrics

Sequential surface reactions of trimethylaluminum and water vapor have been used to deposit Al2O3 on Si(100) surfaces. The self‐limiting nature of the surface reactions allows precise control of the thickness of the deposited layers and gives rise to films with highly conformal step coverage. High quality dielectrics have been deposited at temperatures as low as 100 °C. Resistivities of 1017 Ω cm, breakdown strengths of 8×106 V/cm, and interface‐state densities of 1011 states/eV cm2 have already been achieved and they suggest possible applications as a gate insulator or a dielectric passivation layer.
Oil Spill Remediation Using Magnetic Separation

Magnetic separation technology was applied to remove dispersants and crude oil from water with magnetite and maghemite. Maghemite exhibited rather constant removal efficiency for dispersants regardless of surfactant types, while magnetite exhibited higher removal efficiency for anionic surfactant, and the efficiency was higher in deionized water than in salty water that contains more ions. Sorption of the dispersants to magnetite can be explained with electrostatic attraction, while binding of the dispersants to maghemite can be described with electrostatic attraction as well as with the structural characteristics that provide high sorption capacity. The result from a water bath experiment, which was to test the collection efficiency of magnetic particles from water, indicated that the recovery efficiency of magnetic particles was nearly 100% after the dispersants had been sorbed. More than 80% of the oil was collected when the magnetite-to-oil ratio was more than 0.89, while the same percentage of oil wa.
Role of chromatin regulators AtRING1 and AtZRF1 in Arabidopsis growth and development

In plants as in animals, the Polycomb Group (PcG) proteins play key roles in diverse developmental processes by repressing the expression of genes. These proteins work in multi-protein complexes, among them the best characterized ones are Polycomb Repressive Complex 1 (PRC1) and PRC2. Although PRC2 was extensively studied in Arabidopsis, it is only recently that components of PRC1 were identified in plants and their function mechanism remains largely elusive. My thesis work focused on the characterization of AtRING1A, one of the PRC1 core subunits, and of AtZRF1, a protein proposed as a reader of the histone H2A-monoubiquitin (H2Aub1) downstream to the PRC1 function. My results show that a total loss-of-function of AtRING1A, by CRISPR/Cas9 gene editing, leads to partial embryonic lethal and callus-formation of seedlings in Arabidopsis. Several mutations within the RAWUL domain at the C-terminus of AtRING1A are better tolerated and induce several defects in plant vegetative growth, flowering time, floral organ formation and seed production. My molecular data indicate a role of the RAWUL domain in H2Aub1 deposition in vivo and suppression of several key developmental genes. Our characterization of loss-of-function of AtZRF1 provides important detailed information about its function in the regulation of cell division and cell differentiation.
Nutrient Status in Oak Forests in Galicia, Northwest Spain: Foliar and Soil Concentration

The concentration of edaphic and foliar nutrients is an important factor in assessing the nutritional status of an ecosystem. This article presents data on the macronutrients in leaves and topsoil in Quercus robur forests located in northwest Spain. The aim is to evaluate the nutrient level explained by foliar and soil standard values and establish their relationships. We calculated the following nutrients: nitrogen, phosphorus, potassium, calcium, and magnesium. Plots 10 × 10 m were laid out and replicated three times. Soil was collected once per month with three samples from the topsoil, and leaves were collected once every 2 months during the vegetative period. Within the results, we emphasize the absence of nutrient deficiencies. The leaf macronutrient results differed by stand. Soil fertility can be considered low to medium, except for phosphorus and potassium, as compared with soils under pine and eucalyptus. There was no relationship between macronutrients in topsoil and leaves.
Nickel-titanium alloy electrode as a sensitive and stable LCEC detector for carbohydrates

A highly sensitive and stable amperometric detector for the liquid chromatographic (LC) analysis of carbohydrates has been developed on the basis of the use of a nickel-titanium (Ni-Ti) alloy electrode. Between an applied potential of +0.40 and +0.60 V vs Ag/AgCl, the Ni is electrochemically oxidized to the Ni(III) state as the nickel oxyhydroxide. This Ni(III) is believed to be the active form that oxidizes the carbohydrate in an ec catalytic sequence. This catalysis is similar to that proposed for a pure nickel electrode
Investigation of Porosity and Permeability Impairment in Sandstones by X-ray Analysis and Simulation

Abstract Both porosity and permeability constitute the major parameters in core analysis. In this study, the variation of these two parameters along a sandstone core sample was investigated during formation damage. A water-based drilling fluid was dynamically circulated through the core sample for three different time intervals of 15 min, 45 min, and 60 min at 100 psi circulation pressure. The core sample was analyzed using x-ray digital radiography by sectional image approach. The differences in the porous media due to fines migration by drilling fluid were examined. Digital image subtraction method was applied by using an in-house simulator developed to run with MATLAB® to determine porosity. The experimental results obtained by dynamic circulation and x-ray imaging were compared with the results obtained by using a numerical fines migration simulator. Consistent matches between the experimental and numerical results were observed indicating that porosity and permeability impairments with distance can be described accurately.
INTAKE, DIGESTA FILL AND FLOW KINETICS PRE- AND POSTPARTUM

Voluntary intake of pellets increased from 45.99 to 73.15 g/BW0.75, gastrointestinal tract fill increased from 1.63 to 2.73%/BW and mean residence time for liquids was reduced by 3.5 and for particles by 6 h in ewes postpartum compared to prepartum. Key words: Gastrointestinal tract fill, passage rate sheep
Desertification impact assessment in Egypt using low resolution satellite data and GIS

In this study, desertification processes and their impact on land cover changes in Egypt from 1992 to 2000 were analyzed using low‐resolution satellite data. Two images of NOAA‐AVHRR and SPOT vegetation data acquired in November 1992 and 2000 were used to assess desertification and changes of agricultural lands in Egypt. A supervised classification of the two images was carried out using the Maximum Likelihood technique. Change image was produced using classified images, through a cross‐tabulation Geographic Information Systems (GIS) module, to assess the trend and form of land cover changes. It was found that agricultural land increased by about 14.3% during the study period, in particular, around the Nile River Delta and around the Northern Lakes of Egypt. The newly cultivated lands were extracted mainly from desert and salt marshes. At the same time, parts of the agricultural lands were turned into degraded land due to desertification and urban expansion.
Effect of Coal Gases on Electrochemical Reactions in the Direct Carbon Fuel Cell System

Abstract — Various carbonaceous fuels were evaluated in a Direct Carbon Fuel Cell (DCFC) system as energy sources. In order to investigate the characteristics of electrochemical reaction of various fuels in DCFC, three coals, such as Shenhua coal, Adaro coal, and Openblue coal which have different content of fixed carbon and volatile matter, were selected in this research. The characteristics of electrochemical reactions of fuels were investigated at 700 ℃ by potentiostatic method of the fuel cell and the effect of fuels properties is also discussed. The effect of gases from coals was investigated by using raw coal state and char state in present work. The gases, such as H 2 , CH 4 , CO and CO 2 , were detected in the exhaust gas of anode side by thermal decomposition of coal. It is confirmed that these gases have an effect on the electrochemical reaction on DCFC system by comparing of current density of raw coal and char. were carbonized to remove volatile matter. The potential and
Hydrate formation using water spraying in a hydrophobic gas: A preliminary study

We examined the idea of spraying water against a copper block exposed to a hydrate-forming gas, while the block was steadily chilled at its backside. This spray/cooling assembly was expected to enable the simultaneous hydrate formation at, and the heat removal from, the surface of the copper block. Emphasis was placed on visual observations to understand the nature of hydrate-formation with this spray/cooling assembly.
Chlorinated organics removal from water by plasma‐graft filling polymerized membranes

It was reported that this type of membrane showed high separation properties for removal of dissolved organics from water. Methylacrylate, ethylacrylate and n-butylacrylate (BA) were employed as the grafting monomers, and the filling type membranes were prepared by plasma-graft polymerization technique. Ethylacrylate grafted membranes and BA grafted membranes showed high selectivity for chlorinated organics from water. The BA grafted membrane showed higher selectivity and permeability than a cross-linked BA membrane in literature. The grafted chains which filled in pores were linear, and the free volume of the grafted polymer might be larger than cross-linked polymer whose chain mobility was reduced by cross-linking. Moreover, swelling of the filling polymer was effectively suppressed by the porous substrate matrix. So, the filling type membrane showed both high selectivity and permeability. The order of selectivity for chlorinated organics was methylacrylate < ethylacrylate < BA grafted membranes. The order is in good agreement with the grafted polymer hydrophobicity. In this study, more hydrophobic polymers were used as the grafted polymer, such as poly(ethylhexylacrylate) (SA). 1,1,2-trichloroethane (TCE) was used as a model organic or halogenated hydrocarbon contaminants.
Temperature and ph-dependent swelling behavior of poly(N-isopropylacrylamide) copolymer hydrogels and their use in flow control

Poly(N-isopropylacrylamide) (PNIPAAM) copolymer gels with acidic and basic comonomers of various molar ratios were prepared by radical polymerization. The relationship between the swelling behavior of the gels and the copolymerization ratio was studied experimentally at different temperatures and in various pH value buffer solution. The results of the experiments revealed that the transition temperatures of the PNIPAAm copolymer gels were changed in proportion to the monomer ratio used in copolymerization. The pH value of the buffer solution strongly affected the swelling ratio and some of the transition temperatures of the gels. The PNIPAAm copolymmer gels were used in a chemomechanical valve. The liquid flows directly through a gel actuator, which consists of a cylindrical actuator chamber filled with small particles of the sensitive cross-linked polymer. The flow rate as well as the pressure drop was measured in dependence on the solvent properties. With the presented experimental arrangement it could be shown that sensitive polymers can be used for controlling the flow in dependence on temperature and pH.
Diseño de mecanismo para la asignación de costos derivados de reducir emisiones provocados por la generación de energía eléctrica

Nicchi F. Diseño de mecanismo para la asignación de costos derivados de reducir emisiones provocados por la generación de energía eléctrica [en línea]. En: III Encuentro Latinoamericano de Economía de la Energía; 2011 Abr 1819; Buenos Aires: Instituto Argentino de la Energía “General Mosconi”, Universidad Católica Argentina, International Association for Energy Economics. Disponible en: http://bibliotecadigital.uca. edu.ar/repositorio/contribuciones/diseno-mecanismo-asignacion-costos-derivados.pdf [Fecha de consulta: . ]
Hand-held analyser based on microchip electrophoresis with contactless conductivity detection for measurement of chemical warfare agent degradation products

This paper reports on the development of a hand-held device for on-site detection of organophosphonate nerve agent degradation products. This field-deployable analyzer relies on efficient microchip electrophoresis separation of alkyl methylphosphonic acids and their sensitive contactless conductivity detection. Miniaturized, low-powered design is coupled with promising analytical performance for separating the breakdown products of chemical warfare agents such as Soman, Sarin and VX . The detector has a detection limit of about 10 μg/mL and has a good linear response in the range 10-300 μg/mL concentration range. Applicability to environmental samples is demonstrated . The new hand-held analyzer offers great promise for converting conventional ion chromatography or capillary electrophoresis sophisticated systems into a portable forensic laboratory for faster, simpler and more reliable on-site screening.
Monotectic Composite Growth with Fluid Flow

It is a well-known fluid-mechanical phenomenon that thermocapillary forces induce surface convection on a fluid–fluid interface. This so-called Marangoni convection depends on the variation of the surface energy along the interface. In our present work we focus our attention on the evolution of a fibrous monotectic microstructure with liquid L2 fibers. We will show, that the Marangoni convection has a strong influence on the transport of solute in front of the solidification front, despite the flow induced by density differences. The resulting flow field affects the constitutional undercooling and therefore the mean undercooling of a monotectic solidification front. In a previous paper we discussed qualitatively the influence of fluid flow on the microstructure evolution of composite monotetic growth (C. Stocker, L. Ratke, J. Crystal Growth 203 (1999) 582). We introduced an analytical model that takes the density differences of the phases and the surface convection on the L1–L2 surface into consideration. With this extended Jackson and Hunt theory for composite monotectic growth we derived a characteristic equation for the inter-rod distance depending on solidification velocity and temperature gradient. In this paper we develop a more accurate model. We solve numerically the diffusion equation coupled with the Navier–Stokes equation in the L1 phase to find the minimal undercooling for a given velocity and temperature gradient. We derive a Jackson and Hunt diagram and show that the fluid flow leads to a strong dependence of the inter-rod distance on the temperature gradient opposite to eutectic solidification.
Synthesis of nickel nanoparticles. Influence of aggregation induced by modification of poly(vinylpyrrolidone) chain length on their magnetic properties

The reaction of Ni(COD)2 with H2 (3 bar) in CH2Cl2 in the presence of poly(vinylpyrrolidone) (PVP) K 30 leads to air-stable agglomerates of ≈30 nm, composed of individual 3−4 nm fcc Ni particles and displaying a ferromagnetic behavior whereas the same reaction in the presence of PVP K 90 leads to 4 nm, well-dispersed fcc Ni particles displaying a superparamagnetic behavior. In both cases the magnetic moment per atom is similar to the value found for bulk nickel, hence demonstrating the absence of oxidation of the surface of the particles.
Microwave Spectra of Molecules of Astrophysical Interest. XXI. Ethanol (C2H5OH) and Propionitrile (C2H5CN)

The microwave spectra of ethanol (C2H5OH) and propionitrile (ethyl cyanide, C2H5CN) are critically reviewed and supplemented with spectral frequency calculations which include rotational and centrifugal distortion terms in the molecular Hamiltonian. The primary objective of this review is to provide the microwave transition frequencies applicable to molecular radio astronomy for the ground vibrational state of the most abundant isotopic forms, namely, 12C2H516OH and 12C2H512C14N. Since the internal rotation and hyperfine splittings for these species have not been resolved in most of the reported laboratory studies and also not detected in the molecular clouds observed by radio astronomers, these splittings have been ignored in the present calculations. All measured rotational transitions are included, however, the predicted transition frequencies were limited to J = 25 for ethanol and J = 30 for propionitrile over the range of 1 GHz to 300 GHz. A complete summary of the laboratory studies of both species .
Mixed-ion linear actuation of PPy and PEDOT in propylene carbonate-triflate electrolytes

Investigations of the actuation properties of free standing PPy and PEDOT films in a propylene carbonate-triflate electrolyte (PC/TBACF3SO3) under isotonic (constant load) conditions are presented in this work. The PPy film showed mixed ion movement during charging and discharging in cyclic voltammetric and chronoamperometric experiments. At a potential of -1.0 V the maximum strain was in the range of 1-2 % whereas at the anodic potential of +1.0 V strains in the range of 3-4 % were observed. Cyclic voltammetry experiments at higher scan rates to 10 mV/s led to a decrease in the anodic strain and an increase in the cathodic strain before it declined at higher scan rates. The free-standing PEDOT films showed mainly cathodic actuation at the potential -1.0 V and the size of actuation was again dependent upon the scan rate. Cation movement is discussed in terms of the immobilisation of CF3SO3- anions during polymerisation. Extended potential step experiments showed good actuation and low creep in the potential range between 0.0 and +1.0 V. The surface morphology (SEM) showed an open porous structure for PEDOT in contrast to the smooth morphology of PPy.
Ein Beitrag zur Pyrochlorstruktur an La2Zr2O7

Von der Verbindung La2Zr2O7 wurden erstmals Einkristalle dargestellt und rontgenographisch untersucht. La2Zr2O7 kristallisiert in der Raumgruppe OFd3m mit der Gitterkonstanten a = 10,786 A. Der fur die Pyrochlorstruktur charakteristische Sauerstoffparameter hat den Wert x = 0,295. Single crystals of the compound La2Zr2O7 were prepared for the first time and examined by x-ray investigations. La2Zr2O7 crystallizes in the space group OFd3m, a = 10.786 A. The free oxygen parameter, which is characteristic for the pyrochlore structure, was found to be x = 0.295.