Miracle-dz/UniFAR-FTUs huggingface dataset:
Quantum chemical and vibrational investigation of sodium exchanged γ-alumina surfaces

The sodium cation is well known as an efficient poison of γ-alumina surface acidity. This poisoning effect has been revealed both by characterization methods and catalytic tests. In this work, we propose an accurate model of sodium exchanged γ-alumina surfaces. On realistic models of hydroxylated γ-alumina surfaces, the location of sodium cation is determined by the use of density functional theory (DFT) methods. For the (100) and (110) surfaces of γ-alumina, the sodium cation is found in a solvated state within an inner solvation sphere complex. Its coordination sphere is constituted by O–μ2, O–μ3 and HO–μ1 surface groups. The stretching frequency of these HO–μ1 groups is shifted, leading to the appearance of a new band predicted and observed at about 3754 cm−1 on the IR spectrum.
Transparent superhydrophobic/superhydrophilic TiO2-based coatings for self-cleaning and anti-fogging

A stable titanate nanobelt (TNB) particle suspension was prepared by a hydrogen-bond-driven assembly of pre-hydrolysed fluoroalkylsilane (FAS) on its surface. A one-step electrophoretic deposition was applied to fabricate a transparent cross-aligned superhydrophobic TNB/FAS film on a conducting glass substrate. By controlling the deposition time, we have shown the transition between a “sticky” hydrophobic state (high contact angle with strong adhesion) and a “sliding” superhydrophobic state (high contact angle with weak adhesion). The optical transmittance can reach as high as 80% throughout most of the visible light region of the spectrum. These coatings have also displayed high chemical stability and self-cleaning ability. Upon heating the hydrophobic coatings at 500 °C, the TNB coating transforms into a porous TiO2(B) structure with superhydrophilic behavior and could be used for anti-fogging applications. With this TiO2-based system, we have demonstrated three different wetting states: superhydrophobicity with weak adhesion, high hydrophobicity with strong adhesion, and superhydrophilicity with immediate water spreading. Moreover, this work has also demonstrated superhydrophobic TNB/FAS films with high chemical stability and good self-cleaning performance and superhydrophilic pore-like TiO2(B) films with rapid water spreading and excellent anti-fogging ability.
From collisions to clusters: first steps of sulphuric acid nanocluster formation dynamics

The clustering of sulphuric acid with base molecules is one of the main pathways of new-particle formation in the Earth's atmosphere. First step in the clustering process is likely the formation of a (sulphuric acid)1(base)1(water)n cluster. Here, we present results from direct first-principles molecular dynamics collision simulations of (sulphuric acid)1(water)0, 1 + (dimethylamine) → (sulphuric acid)1(dimethylamine)1(water)0, 1 cluster formation processes. The simulations indicate that the sticking factor in the collisions is unity: the interaction between the molecules is strong enough to overcome the possible initial non-optimal collision orientations. No post-collisional cluster break up is observed. The reasons for the efficient clustering are (i) the proton transfer reaction which takes place in each of the collision simulations and (ii) the subsequent competition over the proton control. As a consequence, the clusters show very dynamic ion pair structure, which differs from both the static structure optimisation calculations and the equilibrium first-principles molecular dynamics simulations. In some of the simulation runs, water mediates the proton transfer by acting as a proton bridge. In general, water is able to notably stabilise the formed clusters by allocating a fraction of the released clustering energy.
Influence of poling and annealing on the nonlinear dielectric permittivity of PVDF-TRFE copolymers

The linear and second order permittivities of as-prepared and annealed, poled and unpoled PVDF-TRFE 56/44 mol% copolymer film are investigated as a function of temperature. In contrast to annealed PVDF-TRFE, the linear permittivity of unannealed PVDF-TRFE and its temperature dependence is not influenced by poling. This effect can be explained by the existence of domain walls in the crystalline regions of annealed samples, while the smaller crystallites in unannealed samples are always in a single domain state. Thus the poling degree dependence of the linear permittivity of annealed samples may therefore be an effect of domain wall motion. The second order permittivity is a measure of the remanent polarization. Samples poled before the first annealing exhibit a small persistent polarization that remains stable in the paraelectric phase, in contrast to samples which remain unpoled before annealing. This non-switchable polarization is unchanged after several heating cycles and even after poling in the opposite direction. An explanation for this fixed polarization are non-switchable dipoles which form an intermediate phase between the crystalline and the amorphous phase.
A Medium Flow, High-Resolution Vienna DMA Running in Recirculating Mode

In this work we present the latest design of the Vienna type Differential Mobility Analyzer (DMA). The so-called UDMA is specially designed for high-resolution mobility measurements for the particle size range between 1 and 5 nm and has been optimized to be combined with a mass spectrometer to provide a well-defined mobility fraction of molecular clusters. As the UDMA is designed for this narrow size range it features high-resolution mobility measurements already at flow rates of approximately 700 L/min, marked as medium flow conditions. This readily allows operating the UDMA in a recirculating sheath air flow system with gas cleaning filters, as the control over the purity of the sheath air is crucial for operating the UDMA inline with a mass spectrometer or other carrier gas sensible devices. The performance of the newly developed UDMA was tested by the analysis of well-defined molecular clusters produced by an electrospray source and compared with one of the state-of-the-art high resolution DMAs also known as “Attoui DMA. ” For the UDMA, a relative FWHH of the transfer function of 2.5% in mobility-size was found for the monomer clusters of Tetraheptylammoniumbromide (THAB) at 1.44 nm mobility equivalent diameter.
A Facile One Post Synthesis of Pyrano(2,3-c) Pyrazoles with Implement of Various Basic Catalysts and its Biological Evaluation

A series of pyrano[2,3-c]pyrazoles, was efficiently synthesized via one-pot, multi component reaction(MCRs) of 3-amino-1H-pyrazol-5(4H)-one, aromatic aldehydes and malononitrile in the presence of various basic catalyst. The key advantages of this process are high yields, shorter reaction times, easy work-up, and purification of products by non-chromatographic method.
Electrical Properties of Nanocrystalline Tungsten Trioxide

Tungsten oxide is a material of significant interest for applications in several areas. It can, for example, be used as the electrochromic film in smart windows. Tungsten trioxide nanoparticles were produced using an advanced gas evaporation unit in which the tungsten was oxidized in low pressure ambient air. The tungsten trioxide particles were formed via vapor condensation and were deposited by gas deposition technique to avoid coagulation effects. The average size of the primary particles was around 5 nm, depending on the heating power and the pressure. The particles exhibited a body centred cubic structure. The impedance spectrum of particle deposits showed resonance and negative capacitance effects. The correlation between fabrication conditions, structure and impedance spectrum is discussed.
Liquid scintillation counting techniques for the radioassay of [14C] melanin

The radioactive melanin used in this study was extracted from the cell walls of the fungus Aspergillus nidulans after growth in the presence of 14C-labelled precursors. The counting systems investigated comprised solid samples suspended in a liquid scintillator with or without silica gel, solubilized samples blended in a liquid scintillator and solubilized samples adsorbed on to glass-fibre discs wich were suspended in a liquid scintillator. Results obtained by counting solid samples with an end window detector are compared with the liquid scintillation data. High counting efficiencies were realized with the glass-fibre disc method which is recommended for the assay of soluble samples. Liquid scintillation counting of silica gel suspensions was vastly superior to end window counting for the assay of solid samples. The data suggest that 14C-labelled materials of a particulate or highly pigmented nature can be counted with high efficiency in a liquid scintillation system.
Preparation and Properties of Chitosan Graft Copolymer Nanoparticles Using Potassium Diperiоdatоnickelate

Nanoparticles comprising chitosan-graft-poly (methyl methacrylate) (CS-g-PMMA) copolymer were successfully synthesized in aqueous solution by using potassium diperiоdatоnickelate (Ni (IV)) as an initiator. The nanoparticles were characterized in terms of Fourier transform infrared (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The results indicated that chitosan was covalently linked to poly (methyl methacrylate) (PMMA) and the particles were uniform, spherical and well dispersed with narrow size distribution. Paclitaxel-loaded nanoparticles were prepared and in vitro release showed that these nanoparticles provided an initial burst release followed by a slowly sustained release for more than 16 days. Therefore, this process method would be used for synthesizing natural polymer graft copolymer nanoparticles with wide prospect.
Phosphorescence and the True Lifetime of Triplet States in Fluid Solutions

Phosphorescence has been observed in a highly purified fluid solution of naphthalene in 3‐methylpentane (3‐MP). The phosphorescence lifetime of C10H8 in 3‐MP at −45°C was found to be 0.49 ± 0.07 sec, while that of C10D8 under identical conditions is 0.64 ± 0.07 sec. At this temperature 3‐MP has the same viscosity (0.65 CP) as that of benzene at room temperature. It is believed that even these long lifetimes are dominated by impurity‐quenching mechanisms. Therefore it seems that the radiationless decay times of the lowest triplet states of simple aromatic hydrocarbons in liquid solutions are sensibly the same as those in the solid phase. A slight dependence of the phosphorescence lifetime on solvent viscosity was observed in the temperature region, −60° to −18°C. This has been attributed to the diffusion‐controlled quenching of the tiplet state by a residual impurity, perhaps oxygen. Bimolecular depopulation of the triplet state was found to be of major importance over a large part of the triplet decay. Th.
Architecture of modified silica resin coatings with various micro/nano patterns for fouling resistance: microstructure and antifouling performance

As an environmentally friendly antifouling strategy, a series of textured modified silicone surfaces with different textures, shapes and surface roughnesses were fabricated by mimicking the microstructures of abrasive paper via a simple replication method. The physical and chemical properties of the as-prepared coatings were systematically characterized by FT-IR spectroscopy, SEM and contact angle measurements. The antifouling efficacy of all coatings was evaluated by recording the settlement of fouling microalgae, including Nitzschia closterium f. minutissima, Phaeodactylum tricornutum and Chlorella, in the laboratory. The results indicated that the positive and negative replicas of both 800-grit and 1200-grit abrasive paper with morphology feature sizes larger than algae size encouraged the algae settlement. Only the positive replica of 5000-grit abrasive paper whose morphology feature size was smaller than algae size was effective in inhibiting N. closterium, P. tricornutum and Chlorella, and the reduction ratios were 49%, 75% and 81%, respectively. The positive replica of 7000-grit abrasive paper can reduce the amount of N. closterium and P. tricornutum by 29% and 57%, respectively. But it can't inhibit the settlement of Chlorella. The effect of surface morphology and wettability on the antifouling performance of textured coatings was discussed.
Ordered mesoporous Co3O4 spinels as stable, bifunctional, noble metal-free oxygen electrocatalysts

We report the use of noble metal-free ordered mesoporous Co3O4 spinels (meso-Co3O4), templated from KIT-6 mesoporous silica, as highly active and stable bifunctional electrocatalysts for both oxygen evolution and reduction reactions (OER and ORR, respectively). The meso-Co3O4 nanostructures showed high activity for OER in an alkaline medium (0.1 M KOH), which makes them comparable to the most active Ir/C catalyst and better than Co3O4 nanoparticles (NPs) and the Pt/C catalyst. Furthermore, meso-Co3O4 exhibited enhanced stability, compared to Co3O4 NPs. The enhanced activity and stability of meso-Co3O4 over Co3O4 NPs could be attributed to its high surface area and structural stability of the gyroid network structure in the meso-Co3O4 catalysts. The meso-Co3O4 nanostructures also showed promising activity for ORR and exhibited a methanol-tolerance superior to the Pt/C catalyst. The total overpotential of meso-Co3O4 for OER (at 10 mA cm−2) and ORR (at −3 mA cm−2) was 1.034 V, which is on a par with noble metal-based catalysts. This work demonstrates that directing metal oxides into mesostructures is a promising means of preparing highly active, stable, bifunctional oxygen electrocatalysts that can potentially replace expensive noble metal-based catalysts. This design strategy can be extended to other reactions relevant to energy conversion and storage applications.
Spark ignition in a turbulent shearless fuel-air mixing layer: average flame growth rates

A planar methane-air mixing layer with equal velocity in the two streams and approximately homogeneous turbulent intensity and lengthscale has been used to examine non-premixed edge flame speed following spark ignition. The flame was visualized with a high-speed camera and the flame’s edges in the upstream, downstream and cross-stream directions have been identified and their average rate of evolution allowed an estimate of the average absolute flame speed. By subtracting the uniform mean velocity in the corresponding direction resulted in estimates of the mean relative edge flame speed. This quantity was approximately 2.5SL, where SL is the laminar burning velocity of stoichiometric methane-air premixed flames. The results are consistent with DNS of turbulent edge flames.
Suitability of dyed latex bead agglutination test for immunodiagnosis of Karnal bunt (Tilletia indica) teliospores in a single seed of wheat

The immunodiagnosticum for this test was prepared extempore by mixing blue color dyed latex beads (1% suspension) with equal volume of diluted anti-teliospore serum. This test was considered to be better for the detection of solubilized teliosporic antigens over intact teliospores of Karnal bunt. The teliosporic antigens solubilized using sonication and detergent extraction were used for the standardization of the test by optimizing the dilution of latex bead suspension and determining the detection limits. For determining the sensitivity of test, antigen concentration kinetics analysis was performed by adding 15 µl of antibodies sensitized latex beads to 15 µl of different concentrations of solubilized antigens on glass slide. The detection limit of this test was 7.5 µg solubilized teliosporic antigens equivalent to 750 teliospores and suitable for single seed analysis. Small agglutinin formation with solubilized antigen of Puccinia recondita and T. barclayana interpreted on the basis of partial cross reactivity of immunodignosticum with these pathogens. However, no cross reactivity was found with teliosporic antigen(s) of spores of Curvularia lunata, Ustilaga tritici, Helminthosporium sativum, Ustilaginoidea vircns and Alternaria triticina.
Comparison of the Stabilities and Solution Structures of Metal Ion Complexes Formed with 5

Nucleotides and metal ions are involved in the basic metabolic processes of life, participating as substrates in enzymatic reactions in the form of metal ion complexes. Hence, their acid–base and metal-ion coordinating properties were intensely studied in the past years. However, these studies were mainly devoted to nucleoside 50-monophosphates, and to ATP. Only little information exists on nucleoside 50-diphosphates and GTP or ITP. Considering their importance in biochemical reactions, and the recently growing interest on G-proteins, which utilize guanosine 50- triphosphate, a systematic investigation on their coordinating properties is needed. In this study, mainly based on potentiometric pH titrations in aqueous solution at 25 �C and I = 0.1 M (NaNO3), the acidity constants of purine-nucleoside 50- di- and 50-triphosphates (adenosine 50-diphosphate; guanosine and inosine 50-diand 50-triphosphates, here designated as Nu) and the stability constants of their 1:1 complexes formed with ten metal ions (M2+ = Mg2+, Ca2+, Sr2+, Ba2+, Mn2+, Co2+, Ni2+, Cu2+, Zn2+, or Cd2+ ) have been determined. Nucleotides are composed of three units, each of them with potential binding sites for protons and metal ions. In this work, only the properties of the phosphate groups and the nucleobase residues have been investigated in detail, since the sugar moiety interacts with metal ions or releases protons only under special conditions or in the strongly alkaline pH range. Analysis of the collected equilibrium constant data reveals that the stability of all these complexes is largely governed by the metal ion affinity of the phosphate residue. While for the complexes formed with the divalent ions of the second half of the 3d series, including Zn2+ and Cd2+, macrochelate formation is an important property in all the M(Nu) species considered, with GDP, GTP and ITP, the formation of macrochelated species is considerable with all the metal ions studied, including the alkaline earth ions. These macrochelates are formed by the interaction of the phosphate-coordinated metal ion with N7 of the purine moiety. Analysis of the isomer ratio between the open and macrochelated species shows that the formation degree of the latter increases in the series M(AP)cl < M(IP)cl < M(GP)cl (where AP, IP, or GP represents the nucleoside phosphate, i.e., NMP2
Effects of Lewis Number on Scalar Dissipation Transport and Its Modeling in Turbulent Premixed Combustion

The effects of Lewis number (Le) on scalar dissipation rate transport of the reaction progress variable have been studied using 3-dimensional DNS data of freely propagating turbulent premixed flames with global Lewis number ranging from 0.34 to 1.2. It has been found that the effects of dilatation rate become increasingly strong with decreasing Le, and is particularly strong for the Le ≪ 1 flames because of greater rate of heat release. Moreover, increasingly strong flame normal acceleration in flames with decreasing Le gives rise to countergradient transport for the turbulent flux of the scalar dissipation rate, whereas this flux exhibits gradient transport for flames with Le ≥ 1. This turbulent flux is observed to correlate with the behavior of the turbulent scalar flux and this behavior is used to propose an algebraic closure for the turbulent flux of the scalar dissipation rate. The modeling of nonunity Le effects on the unclosed terms arising from the density change across the flame front, the turbulence–scalar interaction, the correlation between scalar gradient and the gradient of reaction rate and the molecular dissipation have been addressed. The extent of reaction progress variable gradient alignment with the most extensive (compressive) principal strain rate is found to increase (decrease) with decreasing Le. This alignment behavior gives rise to a sink contribution arising from the turbulence–scalar interaction in the Le ≪ 1 flames. By contrast, the turbulence–scalar interaction acts predominantly as a source term, although this contribution becomes a sink toward the burned gas side for the Le ≥ 1 flames. It has been demonstrated that existing models for the unclosed terms originating from the density change across the flame front and the turbulence–scalar interaction cannot account for strengthening (weakening) of heat release effects when Le < 1 (Le > 1). Suitable modifications to these models have been proposed to account for nonunity Lewis number effects, and validated using direct numerical simulation data. A simple algebraic expression is suggested that successfully relates the scalar dissipation rate of normalized temperature to the scalar dissipation rate of the reaction progress variable in nonunity Lewis number turbulent flames.
Rubber biosynthesis by a Hevea latex bottom‐fraction membrane

Washed bottom-fraction particles (WBPs), that is, intact membrane-bound vesicles, prepared from the bottom fraction of centrifuged fresh latex, were shown to be active in in vitro rubber biosynthesis (RB) assays. The RB activity catalyzed by WBP enzymes was confirmed by enzyme parameter criteria. A washed bottom-fraction particle membrane (WBM), prepared from WBPs, was even more active in in vitro RB activity. Mg 2+ was a cofactor required for RB enzymes, and the cation chelators EDTA and EGTA inhibited the RB process. The temperature had a strong effect on RB stimulation during the heat pretreatment of the WBM before RB assays. A detergent also proved to a strong RB stimulator. The anionic detergent SDS, above the critical micelle concentration, was a strong stimulator of WBM activity. This was not observed with the nonionic detergents Triton X-100 and Tween 20. Various temperature ranges used for WBM preincubation showed a sharp rise in RB activity above 70°C. The temperature required for a sharp rise in RB was lowered substantially in the presence of SDS. It was down to 40°C with the combined preincubation but remained constant with an even higher RB activity. Greater rubber formation at a lower temperature was observed in the presence of SDS. A synergistic effect for RB stimulation appeared during the heat pretreatment of WBM in the presence of SDS.
Properties of Tunable Filters with Ferroelectric Capacitors

The range of a tunability of the filter with ferroelectric capacitor is determined by the commutation quality factor (CQF), which takes into account both the tunability of the capacitor under biasing voltage and the loss factor. For effective tuning, the CQF should be high enough (more than 1000). The main goal of the tunable filter synthesis is to provide non-degrading filter performance while tuning, and particularly to keep the same fractional bandwidth. Two different approaches to the tunable filter design are suggested and discussed: the image parameter method and insertion loss method. For both methods the filter structure is suggested and analyzed.
Estimation of Hamaker Constants of Ceramic Materials from Optical Data Using Lifshitz Theory

The Hamaker constants of eight different ceramic materials, 6H-SiC, tetragonal, partially stabilized ZrO{sub 2} (3% Y{sub 2}O{sub 3}), {beta}-Si{sub 3}N{sub 4}, {alpha}-Al{sub 2}O{sub 3}, Y{sub 2}O{sub 3}, sapphire (single-crystal {alpha}-Al{sub 2}O{sub 3}), MgO, MgAl{sub 2}O{sub 4}, and fused silica, across air, water, and n-dodecane at room temperature and across silica at 2,000 K have been calculated from optical data using the Lifshitz theory. Spectroscopic ellipsometry was used to measure the photon energy dependence of the refractive index, n, and the extinction coefficient, k, in the visible and near-UV range on several important ceramic materials. This relatively simple, nondestructive technique has proved to yield reliable optical data on sintered, polycrystalline materials such as Si{sub 3}N{sub 4}, SiC, ZrO{sub 2}, Al{sub 2}O{sub 3}, and ZnO. For the other materials, Y{sub 2}O{sub 3}, sapphire, MgO, MgAl{sub 2}O{sub 4}, and fused silica, optical data from the literature were used to calculate the Hamaker constants. The calculated Hamaker constants were estimated to be accurate within {+-} 10%.