Miracle-dz/UniFAR-FTUs huggingface dataset:
Role of excited state photoionization in the 852.1 nm Cs laser pumped by Cs-Ar photoassociation

Photoionization of Cs (6p 2P3/2) atoms during the operation of a Cs D2 line (852.1 nm: 6p 2P3/2→6s 2S1/2) laser, pumped by free→free transitions of thermal Cs-Ar ground state pairs, has been investigated experimentally and computationally. Photoexcitation of Cs vapor/Ar mixtures through the blue satellite of the D2 transition (peaking at 836.7 nm) selectively populates the 2P3/2 upper laser level by the dissociation of the CsAr excited complex. Comparison of laser output energy data, for instantaneous pump powers up to 3 MW, with the predictions of a numerical model sets an upper bound of 8 × 10−26 cm4 W−1 on the Cs (6p 2P3/2) two photon ionization cross-section at 836.7 nm which corresponds to a single photon cross-section of 2.4 × 10−19 cm2 for a peak pump intensity of 3 MW cm−2.
[Fe(bipy)(CN)4]- as a Versatile Building Block for the Design of Heterometallic Systems: Synthesis, Crystal Structure, and Magnetic Properties of PPh4[FeIII(bipy)(CN)4]·H2O, [{FeIII(bipy)(CN)4}2MII(H2O)4]·4H2O, and [{FeIII(bipy)(CN)4}2ZnII]·2H2O [bipy = 2,2‘-Bipyridine; M = Mn and Zn]

The new cyano complexes of formulas PPh4[FeIII(bipy)(CN)4]·H2O (1), [{FeIII(bipy)(CN)4}2MII(H2O)4]·4H2O with M = Mn (2) and Zn (3), and [{FeIII(bipy)(CN)4}2ZnII]·2H2O (4) [bipy = 2,2‘-bipyridine and PPh4 = tetraphenylphosphonium cation] have been synthesized and structurally characterized. The structure of complex 1 is made up of mononuclear [Fe(bipy)(CN)4]- anions, tetraphenyphosphonium cations, and water molecules of crystallization. The iron(III) is hexacoordinated with two nitrogen atoms of a chelating bipy and four carbon atoms of four terminal cyanide groups, building a distorted octahedron around the metal atom. The structure of complexes 2 and 3 consists of neutral centrosymmetric [{FeIII(bipy)(CN)4}2MII(H2O)4] heterotrinuclear units and crystallization water molecules. The [Fe(bipy)(CN)4]- entity of 1 is present in 2 and 3 acting as a monodentate ligand toward M(H2O)4 units [M = Mn(II) (2) and Zn(II) (3)] through one cyanide group, the other three cyanides remaining terminal. Four water molecules.
Relativistic adiabatic time-dependent density functional theory using hybrid functionals and noncollinear spin magnetization

We report an implementation of adiabatic time-dependent density functional theory based on the 4-component relativistic Dirac–Coulomb Hamiltonian and a closed-shell reference. The implementation includes noncollinear spin magnetization and full derivatives of functionals, including hybrid generalized gradient approximation (GGA) functionals. We avoid reducing the generalized eigenvalue problem to half the dimension involving the square of excitation energies since this may introduce spurious roots and also squares the matrix condition number. Rather we impose structure in terms of hermiticity and time reversal symmetry on trial vectors to obtain even better reductions in terms of memory and run time, and without invoking approximations. Further reductions are obtained by exploiting point group symmetries for D2h and subgroups in a symmetry scheme where symmetry reductions translate into reduction of algebra from quaternion to complex or real. For hybrid GGAs with noncollinear spin magnetization we derive a new computationally advantageous equation for the full second variational derivatives of such exchange-correlation functionals. We apply our implementation to calculations on the ns2 ns1np1 excitation energies in the Zn, Cd, and Hg atoms (n = 4–6) and (vertical) excitation energies of UO; and we test the performance of various functionals by comparison with experimental data (group 12 atoms) or higher-level computational results (UO). The results indicate that the adiabatic local density approximation (ALDA) is a good approximation for some GGA functionals, but not all. Furthermore, the results also indicate that ALDA is an extremely bad approximation for hybrid functionals, unless one only employs ALDA for the pure DFT contribution to the exchange-correlation kernel and retains the fraction of exact exchange; we denote this approximation ALDAh. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Modeling of electron elastic and inelastic scattering

The role of the form of the elastic and inelastic cross section in Monte Carlo simulations of electron–solid scattering has been studied to understand the processes whereby energy is deposited by electrons as they traverse thin films. Specifically we are interested in these phenomena as they relate to proximity effects in electron‐beam lithography and the detection of electrons by a Schottky diode with a patterned absorber overlayer. Lithographic point and line spread functions have been measured in three resist materials. We show that the inclusion of discrete inelastic scattering events whereby fast secondaries are generated is essential for matching simulation and experiment. The secondaries are crucial in determining the shape of the spread functions in the 0.1–1 μm regime and must be included to model proximity effects. Further, the fitting of line spread function simulations to experiment allows the accurate prediction of dot spread functions and applied dose thresholds as well as three dimensional .
Ab initio investigations on the crystal structure, formation enthalpy, electronic structure, chemical bonding, and optical properties of experimentally synthesized isoreticular metal–organic framework-10 and its analogues: M-IRMOF-10 (M = Zn, Cd, Be, Mg, Ca, Sr and Ba)

The equilibrium solid-state structure, electronic structure, formation enthalpy, chemical bonding, and optical properties of IRMOF-10 and its alkaline earth metal analogues M-IRMOF-10 (M = Cd, Be, Mg, Ca, Sr, Ba) have been investigated with density functional calculations. The unit cell volume and atomic positions were fully optimized with the GGA functional. This supplements the incomplete experimental structural parameters available for Zn-IRMOF-10. The calculated bulk moduli decrease monotonically from Zn to Cd, and from Be to Ba, and indicate that Zn-IRMOF-10 and its analogues are relatively soft materials. The estimated bandgap values are in the range 2.9 to 3.0 eV, indicating nonmetallic character. Importantly, the bandgaps within the M-IRMOF-10 series (containing a rather long 4,4′-biphenyldicarboxylate linker) are smaller than those within the M-IRMOF-1 series (shorter benzene dicarboxylate linker). The optical properties (dielectric function e(ω), refractive index n(ω), absorption coefficient α(ω), optical conductivity σ(ω), reflectivity R(ω), and electron energy-loss spectrum L(ω)) of the M-IRMOF-10 series were computed. The observation of very small reflectivities over a wide energy range suggests possible uses in hybrid solar cell applications. The main characteristics of the optical properties are similar for the whole series although differences are seen in the details. An analysis of chemical bonding in the M-IRMOF-10 series reveals as might be anticipated that M–O bonds are largely ionic whereas C–O, C–H and C–C exhibit mainly covalent interactions. The BOP values of M–O decrease through the series when going from Zn to Cd, and from Be to Ba, i.e. the ionicity increases and the covalency decreases for the M–O bonds.
Organic ionic plastic crystal-based electrolytes for solid-state dye-sensitized solar cells

An organic ionic plastic crystal, 1-ethyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl) imide (P12TFSI), was synthesized and doped with a room temperature ionic liquid, 1-propyl-3-methylimidazolium iodide (PMII). The prepared PMII/P12TFSI solid-state electrolytes were employed for dye-sensitized solar cells (DSSCs), without using any volatile organic solvent. The fabricated solid-state DSSCs yielded a power conversion efficiency of 5.12% under simulated air mass 1.5 solar spectrum illuminations at 50 mW cm−2. The superior long-term stability of the fabricated solid-state DSSCs indicated that the synthesized PMII/P12TFSI solid-state electrolytes could overcome the drawbacks of cells containing volatile solvents.
Ion-neutral chemistry at ultralow energies: dynamics of reactive collisions between laser-cooled Ca+ ions and Rb atoms in an ion-atom hybrid trap †

Cold chemical reactions between laser-cooled Ca+ ions and Rb atoms were studied in an ion-atom hybrid trap. Reaction rate constants were determined in the range of collision energies ⟨E coll⟩/k B=20 mK-20 K. The lowest energies were achieved in experiments using single localised Ca+ ions. Product branching ratios were studied using resonant-excitation mass spectrometry. The dynamics of the reactive processes in this system (non-radiative and radiative charge transfer as well as radiative association leading to the formation of CaRb+ molecular ions) have been analysed using high-level quantum-chemical calculations of the potential energy curves of CaRb+ and quantum-scattering calculations for the radiative channels. For the present low-energy scattering experiments, it is shown that the energy dependence of the reaction rate constants is governed by long-range interactions in line with the classical Langevin model, but their magnitude is determined by short-range non-adiabatic and radiative couplings which only weakly depend on the asymptotic energy. The quantum character of the collisions is predicted to manifest itself in the occurrence of narrow shape resonances at well-defined collision energies. The present results highlight both universal and system-specific phenomena in cold ion-neutral reactive collisions.
Synthesis and characterization of biocompatible monotyrosine-based polymer and its interaction with DNA

A novel tyrosine-based copolymer containing L-tyrosine (Tyr) and diglycidylether of bisphenol A(DGEBA) was synthesized and studied for its interaction with DNA for potential applications in biological systems. The synthesis of the polymer was optimized by varying monomer ratios using 4(dimethylamino)pyridine (DMAP) as catalyst to yield polymers with Mw of 7500-8000. Further characterization with FTIR, NMR and thermal analysis supported the formation of monotyrosine10 DGEBA polymer. The interaction of 1:1 DGEBA-tyrosine copolymer with DNA was investigated by gel electrophoresis, thermal melting, and fluorescence spectroscopy in ratios ranging from 0.5:1 to 12:1 polymer –DNA (w/w). The copolymer was seen to lend stability to the DNA without damaging it and demonstrated endonuclease resistivity that is conducive for biological applications. Scanning Electron Microscopy, Dynamic Light Scattering and Zeta Potential studies of the polymer-DNA complex also 15 established that the polymer is capable of encapsulating DNA leading to the formation of the DNApolymer polyplex nano-assembly. The potential of the polymer for biological applications was further reinstated by its non-cytotoxicity.
Characteristics of Gelatin from Giant Grouper (Epinephelus Lanceolatus) Skin

Gelatin extraction from the skin of giant grouper (Epinephelus lanceolatus) was conducted by acid process with a yield of 20.27 g/100 g wet skin sample. The characteristics of extracted gelatin from giant grouper was investigated in this study, and further compared to that from commercial tilapia. Results showed that when compared to commercial tilapia, giant grouper had lower levels of bloom strength and foam formation ability, but greater values of viscosity, foam stability, and lightness (L*) on gelatin skin. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis revealed three high-bands intensities of major protein components of giant grouper skin gelatin, representing α1-chain, α2-chain, and β-components, and was similar to that of standard calf skin collagen type I. Compared to giant grouper, commercial tilapia contained extra proteins with molecular weight less than 70 kDa on the sodium dodecyl sulphate-polyacrylamide gel electrophoresis of both skin gelatins.
Cation exchange capacity measurements on illite using the sodium and cesium isotope dilution technique: Effects of the index cation, electrolyte concentration and competition: Modeling

The isotope dilution technique using Na and Cs as index cations was used to determine the cation exchange capacity (CEC) of illite du Puy as a function of background electrolyte composition. The work showed, in accord with previous studies, that the CEC values were in the order Cs-CEC > Na-CEC. Sodium is commonly chosen as the index cation in CEC determinations using the isotope dilution method. The experimentally measured Na-CEC values for Na-illite increased from ∼75 to ∼200 meq kg−1 for NaClO4 concentrations in the range 5.6 × 10−4 to 1.25 × 10−2 M. Cesium CEC determinations showed a much less pronounced trend over a CsNO3 concentration range from 10−3 to 10−2 M. A reference Cs-CEC value of 225 meq kg−1 was chosen. Careful chemical analyses of the supernatant solutions revealed that Ca and Mg at the (sub)umolar level were present in all the determinations, despite the extensive conditioning procedures used. Competition between (Ca + Mg) and Na for the exchange sites was put forward as an explanation for the variation of Na-CEC values. This hypothesis was confirmed in a series of single (45Ca) and double (45Ca plus 22Na) labeling experiments. Calcium-sodium selectivity coefficients ($(_{{\rm{Na}}}^{{\rm{Ca}}}{{\rm{K}}_{\rm{c}}})$(NaCaKc)) were calculated from the experimental data for NaClO4 concentrations from 5.6 × 10−4 to 0.1 M and exhibited a variation from 1.6 to 14.3. A two-site cation exchange model was developed with site capacities and $_{{\rm{Na}}}^{{\rm{Ca}}}{{\rm{K}}_{\rm{c}}}$NaCaKc values for each site: planar site capacity =180 meq kg−1, $_{{\rm{Na}}}^{{\rm{Ca}}}{\rm{K}}_{\rm{c}}^{{\rm{PS}}} = 2$NaCaKcPS=2; type II site capacity = 45 meq kg−1, $_{{\rm{Na}}}^{{\rm{Ca}}}{\rm{K}}_{\rm{c}}^{{\rm{II}}} = 80$NaCaKcII=80. The model was able to predict the Na and Ca occupancies in the Na-CEC experiments over the whole range of NaClO4 concentrations. It is recommended that Cs should be used instead of Na as the index cation for determining the CEC of illite.
CHITOSAN-BASED FUEL CELL MEMBRANES

ABSTRACT Chitosan complex membranes are prepared and characterized at room temperature. They are expected to be used as proton exchange membranes. The studied membranes are cross-linked membranes with sulfuric acid; salt-complexed membranes with lithium nitrate; cross-linked and salt-complexed membranes; plasticized and salt-complexed membranes; cross-linked, plasticized, and salt-complexed membranes; and doped membranes with sulfuric acid. A fixed amount of ethylene carbonate is used as plasticizer. It is found that the ion exchange capacity and hydrogen gas permeability of all membranes is better than that of Nafion membranes. However, their proton conductivities are worse than Nafion membranes. It can be stated that ethylene carbonate does not improve conductivity. An optimum amount of lithium nitrate salt can enhance conductivity. The formation of a sulfate group in cross-linked membranes is necessary for proton conduction. The proton conductivities of 4%cross-linked and 50%LiNO3 membrane before and after acid doping are (3.11±0.40) × 10−2 and (6.64±0.11) × 10−2 S cm−1, respectively. That of Nafion is (8.02±1.19) × 10−2 S cm−1.
Colour and anthocyanin stability of red raspberry jam

Anthocyanin and colour stability of red raspberry jams made from two different varieties (‘Zeva’ and ‘Heritage’) were analysed during 6 months, stored at three temperatures (20, 30 and 37°C). Also the influence of freezing the fruit, previously to jam manufacture, was evaluated. Different anthocyanin composition was detected for both cultivars and while ‘Zeva’ fruit had a higher total anthocyanin content, Heritage variety produced jams with a higher redness hue. The development of browning was directly related to storage temperature but not to thawing or the variety of fruit used. © 1998 Society of Chemical Industry.
Use of Molecular Quantum‐Mechanical Approximations Exemplified in the Energy Calculation of the H3— System

Certain approximations of molecular quantum mechanics are examined. The size of the resultant error due to approximate methods for specific multicenter integral evaluations are cited. Examination of the Sklar approximate multicenter electron repulsion formula together with the generalizations and extensions of Vroeland and Lowdin allow application of the underlying approximation principle to three center nuclear attraction integrals. Specific approximate formulation of these integrals is given.The accumulation of computational errors arising from the many individual integral approximations in the energy evaluation of the linear H3— system is specifically examined. The ground state energy of this system found from the Heitler‐London and Wang‐like treatments were — 70 kcal/mole and — 84 kcal/mole for the Sklar type approximations, — 1 kcal/mole and — 19 kcal/mole for the Mulliken type approximations, and — 26 kcal/mole and — 41 kcal/mole for exact integral evaluations.It is concluded that the Sklar type app.
Separation of 137mBa from its parent 137Cs from an equilibrium mixture using amide incorporated Amberlite IRC-50

A chelating resin was synthesized by incorporating amide group into Amberlite IRC-50, a weakly acidic polymer. The new resin was employed in the separation of 137mBa from its parent 137Cs from an equilibrium mixture. The adsorbed daughter was recovered using 0.01 M EDTA at pH 10.
Origins of Stability in Mixed Bismuth−Indium Clusters†

The electronic structure and stability of neutral and negatively charged BixIny (x = 1−4, y = 1−6) clusters are investigated through anionic photoelectron spectroscopy employing magnetic bottle and photoelectron velocity map imaging experiments. Experimental and theoretical adiabatic and vertical detachment energies of the anionic species containing up to 4 Bi and 4 In atoms are deduced from first principles calculations. Among the BixIny series, many clusters are found to exhibit special stability in the mass spectra, exhibit a large gap between the highest occupied and lowest unoccupied molecular orbitals (HOMO−LUMO gap), and a large formation energy. This stability is rationalized by different mechanisms. Bi2In− is classified as a gas phase Zintl species despite only having three atoms, making it the smallest possible case. Bi3In2−, with 12 valence electrons and a closo structure in agreement with Wade’s rule, is similar to Bi3Ga2−, a gas phase Zintl analogue of Sn52−. Bi4In− and Bi4In2 are both found .
THE STRUCTURE AND ADSORPTION OF DIATOMIC FLUIDS IN DISORDERED POROUS MEDIA. A MONTE CARLO SIMULATION STUDY

The adsorption isotherms for diatomic fluids in disordered porous media have been obtained from grand canonical Monte Carlo computer simulation. A disordered porous medium, or matrix, is prepared by quenching an equilibrium configuration of spherical hard core molecules. In addition, canonical Monte Carlo simulations have been performed for equilibrium binary mixtures that represent counterparts of quenched-annealed systems in question. For the same chemical potential of diatomic molecules at a fixed density of matrix species, the structure and the density of the diatomic fluid in the binary mixture and in the quenched medium are very similar. This behaviour holds also for systems with attractive interactions in the region of high temperatures. Observed similarity of the structural and thermodynamic properties of the mixture and the corresponding annealed fluid-quenched matrix system permits the use of the thermodynamics of the mixture to evaluate some properties of quenched-annealed fluids. Calculations .
Porosity Distribution in Monodisperse and Polydisperse Fixed Beds and Its Impact on the Fluid Flow

This work is devoted to the numerical study of the porosity distribution and gas flow within randomly packed fixed beds comprising polydisperse spherical particles with Rosin–Rammler particle size distribution in a cylindrical container. The fixed bed is numerically generated using gravity-forced sedimentation modeled utilizing the discrete element method. The radial porosity distribution of monodisperse fixed beds was validated against published experimental data and good agreement was achieved. The diameter ratio of smallest to largest particle was varied from 1:2 to 1:5 and then 1:10. The simulation revealed overall porosities of 0.38 for the monodisperse bed and 0.345 and 0.33 for polydisperse beds with ratios of 1:2 and 1:10, respectively. In the second part, the fluid flow within the generated fixed beds was examined using a numerical solution to the incompressible Navier–Stokes equations in the Brinkman–Forcheimer formulation. An analysis of the results showed that in the case of a monodisperse fixed bed and low Reynolds numbers (Re) the pressure drop predicted numerically is close to the values calculated using Ergun's relation. The increase inRe leads to the deviation between the numerical and analytical predictions. This effect is because of channeling due to the sinusoidal distribution of the void fraction close to the wall.
Acidic properties of synthetic saponites studied by pyridine IR and TPD[ndash ]TG of n-propylamine

The acidity of synthetic Zn and Mg saponites exchanged with H+, Al3+, Na+ and K+ has been studied using DRIFTS of adsorbed pyridine and TPD–TG measurements of adsorbed n-propylamine. The characterisation with IR of adsorbed pyridine revealed the presence of a large amount of Lewis acid sites owing to coordinatively unsaturated metal atoms at the edges of the clay platelets. Hardly any Bronsted sites were observed. However, with TPD–TG measurements of n-propylamine it was possible to quantify the number of Bronsted acid sites. In the H+ exchanged clays with high Si/Al ratios the amine/Al molar ratio was found to be near unity. At lower Si/Al ratios the number of acid sites increased non-linearly with the Al content. This study demonstrates that pyridine is a useful probe for determining Lewis acidity. However, to study the Bronsted acidity of H+ exchanged synthetic saponites, reliable quantitative information can only be obtained using n-propylamine.
Micellar Growth, Network Formation, and Criticality in Aqueous Solutions of the Nonionic Surfactant C12E5

We used cryo-TEM and light scattering to study the micellar growth and subsequent network formation in aqueous solutions of the nonionic surfactant C12E5. Cryo-TEM shows the first direct evidence for the existence of connected topology in the vicinity of the critical point and the two-phase separation curve of the C12E5/water micellar system. The coexisting phases within the two-phase region consist of one concentrated and one dilute network of interconnected cylindrical micelles. These findings are consistent with the recent theoretical explanation of criticality and phase separation in certain nonionic surfactant systems as resulting from entropic attraction between network junctions. Away from the two-phase separation curve, we have identified uniaxial micellar growth, with increasing temperature and concentration, into long threadlike micelles. From the power-law dependence of the radius of gyration, RG,z, and the hydrodynamic diameter, DH, on the molecular weight (RG,z, DH ∼ Mwν), we find that thes.