Miracle-dz/UniFAR-FTUs huggingface dataset:
Fluid modeling of a microwave micro-plasma at atmospheric pressure

This paper presents the modeling of an argon micro-plasma produced by microwaves (2.45 GHz) at atmospheric pressure. The study uses a one-dimensional stationary fluid-type code that solves the transport equations for electrons, positive ions Ar + and Ar + 2 , and the electron mean energy, together with Poisson's equation for the space-charge electrostatic field, Maxwell's equations for the electromagnetic excitation field and the gas thermal energy equation. The model uses a simple kinetic scheme for Ar that includes the ground state, an excited state representing the lumped 4s levels, and two ionization states associated to the atomic and the molecular ions. The ions are assumed to be in thermal equilibrium with the neutral gas, having the same temperature profile.
Nitrate leaching from an organic dairy crop rotation: the effects of manure type, nitrogen input and improved crop rotation

Abstract. Four management systems combining high and low livestock densities (0.7 and 1.4 livestock units ha−1) and different types of organic manure (slurry and straw based FYM) were applied to an organic dairy crop rotation (undersown barley – grass–clover – grass–clover – barley/pea – oats – fodder beet) between 1998 and 2001. The effects of the management systems on crop yields and nitrate leaching were measured. In all four years, nitrate leaching, as determined using ceramic suction cups, was higher in the three crops following ploughing of grass–clover than under the barley or grass–clover. Overall, no significant differences in nitrate leaching were observed between the management systems. However, the replacement of the winter wheat crop used in the earlier experimental period (1994–97) by spring oats with catch crops in both the preceding and succeeding winters reduced nitrate leaching compared with the earlier rotation. Increasing the livestock density, which increased manure application by c. 60 kg total N ha−1, increased crop yields by 7 and 9% on average for FYM and slurry, respectively. Yields were 3–5% lower where FYM was used instead of slurry. The experiment confirmed the overriding importance of grassland N management, particularly the cultivation of the ley, in organic dairy crop rotations.
Coupled techniques for arsenic speciation in food and drinking water: a review

Arsenic is ubiquitous in nature appearing in various chemical forms. The toxicity, environmental mobility and accumulation of As in living organisms depends on the form in which the element exists, thus requiring techniques which can identify specific forms whilst retaining their integrity during extraction and pre-treatment prior to measurement. Both organic and inorganic arsenic species may be present in food staples of both terrestrial and marine origin as well as natural waters, at sub ng l−1 to high mg l−1 levels. In this review, the speciation steps (sample preparation, species speciation and detection) most commonly used for the determination of As in food are described. High performance liquid chromatography separation with plasma source mass spectrometry is often the technique of choice due to its versatility, robustness and good detection limits. However, detection systems such as atomic absorption spectroscopy, atomic fluorescence spectrometry, and atomic emission spectrometry are also widely used and covered in this review together with some less utilised techniques.
Measurement and prediction of solubilities of hydrocarbon vapors in molten polymers

The solubilities of m-xylene and nonane vapors in polystyrene and of ethylbenzene and nonane vapors in polybutadiene were measured with a sorption apparatus in the temperature range from 130 to 175°C and 80 to 130°C, respectively.A new expression for the free-volume term derived previously was coupled with UNIFAC to predict activities of hydrocarbons in polymer solutions. In this study, the UNIFAC-FV model has been reexamined and the parameters in the free volume term have been revised. The parameters in the UNIFAC-FV model can be calculated by the group contribution. The model was applied to predict solubilities, activities, or mass-fraction Henry constants for the systems studied here and published in the literature. From comparison of experiment with calculation it is found that the present UNIFAC-FV model can give fairly good predictions of such equilibrium properties of organic vapors in polymers on the basis of a knowledge of molecular structure alone.
Variational Treatment of the HeH + Ion and the β-Decay in HT

The nonrelativistic energies of the HeH+ ion have been computed by the variational method for the ground state and for the first excited 1Σ+ state. The wavefunction employed was a 64‐term generalized James—Coolidge expansion. The computed binding energy of the ground state amounts to De=16448.3 cm−1 at the equilibrium separation Re=1.46324 a.u. The excited state is found to be repulsive.The HeH+ wavefunctions are used to compare quantitatively the theory of β‐decay in molecules with experiment. It is shown that for the HT molecule, the theory predicts the dissociation in at least 17.8% of the events while the corresponding experimental number is 6.8%±1.9%.
A highly selective ratiometric near-infrared fluorescent cyanine sensor for cysteine with remarkable shift and its application in bioimaging

We developed a highly selective ratiometric near-infrared cyanine-based probe CyAC for cysteine (Cys) over homocysteine (Hcy) and glutathione (GSH). Upon the addition of Cys to the solution of CyAC, remarkable shifts in the spectra of CyAC can be monitored (from 770 nm to 515 nm in absorption spectra and from 780 nm to 570 nm in emission spectra). For the first time, the novel strategy that reversibly modulates the polymethine π-electron system by conjugation and removal of the specific trigger moiety was implemented for the generation of a ratiometric cyanine-based sensor. Hydroxy cyanine CyAE was chosen as the flurophore scaffold because the tautomerism (CyAE and CyAK or CyAD) can cause the reversible change in the π-conjugation system of the dyes with large shifts in the spectra. An acrylate group containing a α, β-unsaturated ketone as a functional trigger moiety was incorporated with CyAK to form the sensor CyAC. This specific response for Cys was based on the differences of the kinetics of intramolecular adduct/cyclizations. Moreover, CyAC was successfully applied for bioimaging Cys in living cancer cells. This paradigm by modulation of the polymethine π-electron system in the cyanine dye provides a promising methodology for the design of ratiometric cyanine-based sensors.
Population Balances of Micron-Sized Aerosols in a Bipolar Ion Environment

The present work re-examines the assumptions that are required for a steady-state charge distribution analysis to be valid. First, the common approximation that there are only 11 charge states available to the distribution is relaxed to allow for 201 charge states to be available to the particle distribution. This is found to have large repercussions on the behavior of the distribution for radii greater than 0.5 μm. The steady-state assumption itself is then re-examined by calculating the time required to reach steady state for many different ion-pair production rates and initial particle charge states as a function of radius. In the steady-state model, the ion populations are often assumed to decouple completely from the aerosol; this is shown to be false throughout the troposphere. Finally, the number of positive and negative charge states needed to accurately model a particle population of a given size is determined. © 2013 American Association for Aerosol Research
Chain Dynamics of Ring and Linear Polyethylene Melts from Molecular Dynamics Simulations

The dynamical characteristics of ring and linear polyethylene (PE) molecules in the melt have been studied by employing atomistic molecular dynamics simulations for linear PEs with carbon atom numbers N up to 500 and rings with N up to 1500. The single-chain dynamic structure factors S(q,t) from entangled linear PE melt chains, which show strong deviations from the Rouse predictions, exhibit quantitative agreement with experimental results. Ring PE melt chains also show a transition from the Rouse-type to entangled dynamics, as indicated by the characteristics of S(q,t) and mean-square monomer displacements g1(t). For entangled ring PE melts, we observe g1(t) ∼ t0.35 and the chain-length dependence of diffusion coefficients DN ∝ N−1.9, very similar to entangled linear chains. Moreover, the diffusion coefficients DN remain larger for the entangled rings than the corresponding entangled linear chains, due to about a 3-fold larger chain length for entanglement. Since rings do not reptate, our results point t.
THE COMPARATIVE ANALYSIS OF ECONOMIC DISPATCH AND OPTIMAL POWER FLOW METHODS FOR 22-BUS 380-kV POWER SYSTEM IN TURKEY

In this paper, the economic dispatch and optimal power flow (OPF) methods for the purpose of supplying the load demand with minimum cost is used for 22-bus 380-kV power system in Turkey which consists of 8 thermal plants operated by EUAS (Electricity Generation Co. Inc.)and the results found are analyzed comparatively. The results of analysis are given in tables and figures. The analysis made is implemented by the software using MATLAB. Furthermore, the software can be used for different power systems by using the graphical user interface (GUI). All data used in this study is taken from TEIAS (Transmission System Operator of Turkey) and EUAS.
The Bonding of Trihalide and Bifluoride Ions by the Molecular Orbital Method

A simple molecular orbital treatment is presented to explain the bonding in trihalide ions, X3−, XY2−, and XYZ−, and bifluoride ion, HF2−. The M.O. 's are formed from linear combinations of npσ halogen orbitals, and the 1s hydrogen orbital and stable bonding M.O. 's are obtained without the introduction of higher atomic orbitals. Applications are suggested in prediction of other stable species and low energy reaction intermediates.
Ionic Liquid‐Polymer Gel Electrolytes

New rubbery gel electrolytes have been prepared from room temperature ionic liquids and poly(vinylidene fluoride)-hexafluoropropylene copolymer [PVdF(HFP)]. The ionic liquids employed in these preparations were 1-ethyl-3-methylimidazolium salts of triflate (CF 3 SO 3 - ) and BF 4 - . When properly processed, the ionic liquid-PVdF(HFP) gels are freestanding, flexible films with room temperature conductivities ranging from 1.1 to 5.8 mS cm -1 . Because both the ionic liquids and the PVdF(HFP) are nonvolatile and are thermally stable, the gels can be operated at elevated temperatures without performance degradation. An ionic conductivity of 41 mS cm -1 was measured for a triflate ionic liquid-PVdF(HFP) gel at 205°C.
Influence of corrosion products nature on dechlorination treatment: Case of wrought iron archaeological ingots stored 2 years in air before NaOH treatment

Three wrought iron ingots immersed during 2000 years at 12 m deep in Mediterranean Sea were stored after excavation for 2 years without specific protection in air. After that period, two of them were treated by immersion in a NaOH solution, while the third was used to describe the corrosion system resulting from the storage conditions. This characterisation was achieved by a combination of microanalytical techniques. It could be concluded that though ferrous hydroxychloride β-Fe2(OH)3Cl was the main Cl containing phase at the time of excavation, akaganeite [β-FeO1–x(OH)1+xClx] was the only one present in the rust layers after storage. In order to determine the influence of corrosion products nature on dechlorination treatment, the evolution of a corrosion system composed of both Cl containing phases β-FeOOH and β-Fe2(OH)3Cl has been followed during in situ NaOH experimental treatment. Specific behaviours of each phase to the dechlorination treatment have been revealed.
Phase Structure of Compatibilized Poly(Lactic Acid)/Linear Low-Density Polyethylene Blends

Blends of PLA and linear low-density polyethylene (LLDPE) were compatibilized with glycidyl methacrylate (GMA)–grafted poly(ethylene-octene) copolymer (mPOE). Effects of compatilizer on phase structure of compatibilized PLA/LLDPE were studied by spreading coefficient calculation prediction, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and wide-angle X-ray diffraction (WAXD) analysis. The spreading coefficient calculations, based on experimental and calculated surface tension data, show that mPOE spreads on LLDPE extensively to encapsulate LLDPE completely, which is in good agreement with the results of DSC, SEM, and WAXD analysis. The chemical reaction between the end carboxyl groups or end hydroxyl groups of PLA and epoxy groups of mPOE, which is suggested as the driving force leading to an ideal interfacial adhesion between PLA and the dispersed phase, was confirmed by Fourier transform infrared ray (FT-IR) spectroscopy analysis.
Full‐Color Processible Electrochromic Polymers Based on 4,4‐Dioctyl‐Cyclopentadithiophene

Three soluble electrochromic copolymers based on 4,4-di-octyl-cyclopentadithiophene (DOCPDT): PDOCPDT-OT, PDOCPDT-PT, and PDOCPDT-Cz were synthesized and the electrochromic properties were investigated. Colorimetric analysis revealed that red-colored PDOCPDT-OT, green-colored PDOCPDT-PT and their blue mother polymer PDOCTDT are cathodic coloration polymers. PDOCPDT-Cz is yellow in its neutral state and shows an anodic electrochromism. The structural flexibility, color diversity, processibility and good electrochromic performance make octyl-cyclopentadithiophene-containing polymers prominent candidates for electrochromic applications.
Carbon structures and Mg-based materials for gas sorption

Hydrogen is an alternative energy carrier for both mobile and stationary applications, which can effectively alleviate greenhouse gas emissions and reduce dependence on fossil fuels. The other promising approach in reducing greenhouse gas emissions is carbon capture. Mgbased materials have been considered as a promising hydrogen storage system due to their high hydrogen capacity (up to 7.6 wt.%), high abundance, low cost and lightweight. Different carbon structures have also drawn considerable interests for hydrogen storage and carbon capture. In this research, the nanostructured carbon was produced in a cold plasma reactor designed in-house as additives for improving hydrogen storage properties of Mg-based materials and CO2 storage of MgO. The effects of the plasma reactor’s flow rate, temperature and power were evaluated for the formation of the carbon structures. TEM shows that the carbon consists of spherical particles of 40.8±8.7 nm in diameter and graphene sheets. Further thermal treatment of the plasma carbon was carried out to enhance the surface area. The treatment conditions were optimized through response surface methodology (RSM). The effects of the treatment temperature, time and pressure on BET surface area and yield were studied. The predicted BET surface area and yield by RSM were found to agree with the experimental values. The optimum treatment conditions for the plasma carbon (PC) were found to be: temperature = 950°C and time = 120 min, pressure = 100 kPaCO2 gas flow. The optimized PC was mixed as an additive with 20h-milled MgH2/TiC for improvement of hydrogen storage properties. RSM optimized the mixing time and the content of PC in the (MgH2/TiC + PC) composite. The results demonstrated that both mixing time and the content of plasma carbon (PC) significantly affected the hydrogen storage properties. The effects of the PC, activated carbon (AC) and carbon nanotubes (CNTs) on hydrogen storage properties of MgH2/TiC were studied. PC, AC and CNTs showed positive effects on reducing hydrogen desorption temperature and improving the adsorption kinetics of the 20h-milled MgH2/TiC. PC shows the best effect due to its unique structure. The mechanism of the effects of the three carbon structures on hydrogen storage was discussed. ABSTRACT II The optimized PC was also mixed with MgO, both by ball milling and chemical coprecipitation methods to form porous carbon supported MgO for CO2 storage and separation. The results indicated that the chemically synthesized MgO+PC calcined at 800 °C (referred to as MgO/PC-800) showed the most promising CO2 storage capacity up to 6.16 mmol/g at 25 °C and 1500 kPa CO2 pressure. The introduction of PC improves the CO2 adsorption capacity of the chemical synthesized MgO due to improved surface area. The dual-site Langmuir (DSL) model was employed to predict adsorption equilibria of CO2/H2 gas mixtures, which well simulated the behaviors of pure CO2 adsorption and H2 adsorption, and can be used to predict the binary CO2/H2 gas mixture separation.
Computer Simulation of Ethylene Physisorption on Graphite

Grand canonical Monte Carlo (GCMC) simulations of ethylene physisorption on the basal plane of graphite are reported. The calculated isotherms are compared with experimental results at several temperatures. The maximum surface coverage studied is close to one monolayer. The ethylene molecules are described as six Lennard-Jones interaction sites. Three models are compared to introduce the quadrupolar interactions. The isosteric heat of adsorption at zero coverage is also calculated, and the obtained value is compared with experimental results obtained by other authors.
Determination of Total Chromium in the Marine Sediment Certified Reference Material by Inductively Coupled Plasma Optical Emission Spectrometry after Pressurized Acid Decomposition

(1) The marine sediment (NMIJ CRM 7302a) was directly decomposed with a mixture of 1 mL of hydrofluoric acid, 1 mL of nitric acid and 8 mL of (1 + 1)sulfuric acid in a Teflon sealed vessel at 230°C for 16 h. The total chromium was determined. (2) An indirect acid method after the decomposition of organic materials by H2SO4-HNO3 was compared to a direct acid decomposition method (1). The analytical results of the total-chromium (t-Cr) by methods (1) and (2) coincided with the certified value of the NMIJ CRM 7302a. The direct method of (1) was recommended for a pre-treatment of a marine sediment sample. On the other hand, an electron probe micro-analyzer (EPMA) was applied to an element analysis of the trace precipitation in a direct acid decomposition process in a Teflon-sealed vessel. The white trace precipitation was a crystal of AlF, and the black trace precipitation was carbon. Trace chromium was not detected by the precipitations. How to obtain accurate data from the pre-treatments was discussed regarding the data of this method and other data : that is EPA 3050B, ISO 11466, EPA 3052B, or NAA found from the Union Internationale des Laboratories Indepentants, Inter-Laboratoriy Practice report. The importance of deciding the assigned value was discussed for a statistical evaluation of the data of participants in a proficiency testing. The certified reference materials (CRM) should be furnished by both the sheet decomposition methods of CRM in addition to methods (sheet) for accurate quantitative analyses of the analytes in the CRM.
A Direct Method of Measuring Nuclear Spin-Lattice Relaxation Times

This direct method of measuring nuclear spin-lattice relaxation times is based on Bloch's nuclear induction experiment in which the material investigated is subjected to a magnetic field that is varied several times per second through the value for nuclear resonance. Under certain conditions a simple calculation may be made of the relation between the magnitude of the nuclear induction effect, the relaxation time, and the time intervals between successive passages through resonance. Experimental observation of this relation then determines the relaxation time directly.
Networks of Point Disclinations at the Nematic-Isotropic Interface

In an earlier study, we found that in a mixture of a nematogen with a nonmesomorphic compound, the director takes an oblique orientation at the nematicisotropic interface. In the present paper, we report observations of regular networks of a large number of disclination points on samples with a relatively large area of such an interface.
What Do the Kohn−Sham Orbitals and Eigenvalues Mean?

Kohn−Sham orbitals and eigenvalues are calculated with gradient-corrected functionals for a set of small molecules (H2O, N2, CrH66-, and PdCl42-), varying basis sets and functionals. The calculated Kohn−Sham (KS) orbital shapes, symmetries, and the order and absolute energy of the associated eigenvalues are investigated and compared with those of Hartree−Fock (HF) and one-electron extended Huckel (eH) calculations, as well as experimental ionization potentials. The shape and symmetry properties of the KS orbitals are very similar to those calculated by HF and eH methods. The energy order of the occupied orbitals is in most cases in agreement among the various methods. The order of empty orbitals of a minimal basis set is sometimes interchanged, within that group or with some orbitals resulting from a larger basis calculation. Overall the KS orbitals are a good basisas Baerends suggestedfor qualitative interpretation of molecular orbitals. For the Kohn−Sham eigenvalues we find an approximately linear depen.
Development and Validation of UV Spectrophotometric Method for the Estimation of Kaempferol in Kaempferol: Hydrogenated Soy PhosphatidylCholine (HSPC) Complex

Introduction: Kaempferol (3,5,7-trihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) is a natural flavonoid belongs to subcategory of flavonol family. The Kaempferol – Hydrogenated Soy Phosphatidylcholine (HSPC) Complex was obtained by refluxing and freeze drying method. UV – Visible Spectrophotometric method has been developed for determination of Kaempferol in Kaempferol – HSPC Complex. Objective: A validated UV – Visible spectrophotometric method for determination of Kaempferol in Kaempferol – HSPC complex. Methods: The Kaempferol – HSPC Complex (Phytosomes) were prepared by dissolving both Kaempferol and Hydrogenated Soy Phosphatidylcholine (HSPC) in 1, 4 – dioxane for refluxing up to 2h and freeze dried. The spectrophotometric detection of kaempferol was done at absorption maximum (λmax) of 365 nm and 265 nm using methanol as solvent. The developed method was validated as per ICH guidelines. Result: The Kaempferol content in Kaempferol – HSPC Complex was found to be 79.32% and 79.19% at 365 nm and 265 nm. Kaempferol demonstrated good linearity in concentration range of 2 – 12 µg/ml (r2>0.99) at 365 nm and 2 – 14 µg/ml (r 2 >0.99) at 265nm. Precision and mean recoveries were found to be in the range of (% RSD 0.0957 & 0.0580) and (% RSD 0.1461 & 0.0959) and 99.70 % & 91.85 % at 365 nm and at 265 nm. LOD and LOQ were found to be (0.015µg/ml & 0.0191µg/ml) and (0.0457µg/ml & 0.0579µg/ml) respectively. Conclusion: The developed method was found to be simple, specific, economic, reliable, accurate, precise, reproducible and used as a quality control tool for analysis of Kaempferol. Key Words: Freeze drying, HSPC, Kaempferol, Method validation, UV – Visible spectrophotometer.