Miracle-dz/UniFAR-FTUs huggingface dataset:
The first regioregular head-to-tail poly(3-hexylthiophene-2,5-diyl) and a regiorandom isopolymer: nickel versus palladium catalysis of 2(5)-bromo-5(2)-(bromozincio)-3-hexylthiophene polymerization

Recent research on poly(alkylthiophenes) (PAT) has concentrated on the regularity and structure of the polymer chain of PAT. The 3-alkyl substituent in a thiophene ring can be incorporated into a polymer chain with two different regioregularities: head-to-tail (HT) and head-to-head (HH). Head-to-head linkages can cause defects in the polymer chain. The highest regioregularity reported to date for HT-PAT is 91% (usually 50-60% HT regioregularity). The authors report herein a new and facile synthesis which leads to the first completely head-to-tail regioregular poly(3-hexylthiophene 2,5-diyl) (HT-PHT) and an alternative synthesis which yields an unusual regiorandom PHT with almost equal distribution of different linkages in the polymer chain. Both polymers have been characterized by NMR, IR, elemental analysis, GPC (gel-permeation chromatography), and UV-vis. 11 refs., 2 figs., 1 tab.
Aerosol Aspiration Efficiency of Blunt and Thin-Walled Samplers at Different Wind Orientations

The measured aerosol aspiration efficiency of a thin-walled probe and 5 blunt (thick-walled) samplers was used to compare the aspiration efficiency calculated using the models developed by Belyaev and Levin (1972, 1974) and by Vincent and his colleague (1987, 1995). At 0° wind direction, the model developed by Belyaev and Levin agrees quite well with the experimental value for both the thin-walled probe and the blunt samplers. In this case, the blunt sampler body diameter ( D b ) was used to replace the inlet diameter ( D i ) for the calculation of the Stokes number (St). At 90° and 180° wind directions, the model developed by Vincent and his colleague agrees fairly well with the experimental value. This study shows that the model developed by Belyaev and Levin, at 0° wind direction, can be modified to calculate the aerosol aspiration efficiency by using personal samplers as area samplers. For the model developed by Vincent and his colleague, in addition to personal sampler application, at 90° and 180° wind directions their model can also be used to estimate the aspiration efficiency of area samplers.
Determination of phenolic acids in Prunella vulgaris L.: a safe and green extraction method using alcohol-based deep eutectic solvents

The extraction of natural products with available green and safe solvents is rather limited. Recently, deep eutectic solvents (DESs) have attracted growing interest as sustainable and safe solvents. However, few studies have applied DESs in the extraction and determination of phenolic acids. Therefore, in the present study, DESs (alcohol-based) were applied to extract rosmarinic acid and salviaflaside, which were the predominant phenolic acids in Prunella vulgaris. The extraction yield acted as the comprehensive evaluation index, and a central composite design (CCD) of the response surface liquid/solid ratio methodology (RSM) was employed to further optimize the alcohol-based DES extraction conditions. The results showed that the optimized extraction conditions included a water/DES ratio of 36% (v/v), liquid/solid ratio of 14 mL g−1, extraction temperature of 86 °C and extraction time of 46 min for rosmarinic acid as well as a water/DES ratio of 30% (v/v), liquid/solid ratio of 12 mL g−1, extraction temperature of 89 °C and extraction time of 32 min for salviaflaside in ChCl/ethylene glycol at 1/4 ratio. Under these conditions, the mean experimental value of the extraction yields (3.658 and 1.049 mg g−1 for rosmarinic acid and salviaflaside) corresponded well with the predicted values. Moreover, these experimental values were higher and safer than those obtained from previously reported conventional extraction methods. This study suggests that DESs can be utilized as sustainable and safe extraction media for natural products.
Solid state inclusion compound of S-ibuprofen in β-cyclodextrin: structure and characterisationElectronic supplementary information (ESI) available: crystal and data collection parameters and relevant O⋯O contacts (divided in six different groups) for βCD∶S-Ibu. See: http://www.rsc.org/suppdata/nj/b

A crystalline inclusion complex was isolated from the reaction of β-cyclodextrin (βCD) with aqueous S-(+)-ibuprofen (S-Ibu). The existence of a true inclusion complex in the solid state was confirmed by a combination of powder X-ray diffraction (XRD), single crystal X-ray diffraction, thermogravimetric analysis (TGA), FTIR and 13C CP MAS NMR spectroscopies. The inclusion compound crystallises in the non-centrosymmetric monoclinic space group C2 with a 2∶1 host∶guest stoichiometry. The crystal structure consists of a head-to-head dimer of βCD molecules stacked along the crystallographic c axis, thus forming a slightly tilted channel-type structure.
Copolymerization of a dendronized monomer with styrene and different acrylates: Determination of reactivity ratios

The reactivity ratios for the copolymerization of a first-generation dendronized monomer with styrene and different acrylates are determined. The obtained ratios as well as the copolymer compositions that can be expected are discussed in detail. The influence of the dendron on the polymerization potential of the monomer is estimated by comparing its reactivity to those of linear systems as well as using higher generations of the dendronized monomer. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Reaction of epoxides with triphenylphosphine–thiocyanogen (TPPT): preparation of α-thiocyanatovinyl ketones, vic-dithiocyanates, and vic-dithiocyanatohydrins

A number of epoxides smoothly react with TPPT under mild conditions to give α-thiocyanatovinyl ketones, vic-dithiocyanates, or vic-thiocyanatohydrins, depending on the structures of the epoxides used. The reactions proceed site- and stereo-specifically, to give α-thiocyanatovinyl ketones from αβ-epoxyketones, threo-dithio-cyanate from trans-epoxide, erythro-dithiocyanate from cis-epoxide, and vic-thiocyanatohydrins from 1,1-disubstituted or fused epoxides, respectively. A possible mechanism for these reactions is put forward.
Surface Tension of an Anionic Surfactant: Equilibrium, Dynamics, and Analysis for Aerosol-OT

The equilibrium and dynamic surface tension of sodium bis(2-ethylhexyl) sulfosuccinate (Aerosol-OT) are studied as a function of concentration and ionic strength controlled by the addition of either the monovalent salt sodium chloride or the divalent salt calcium chloride. These data are compared to a surfactant mass-transfer model with a quasi-equilibrium treatment of the electrostatics. The Davies adsorption isotherm and surface equation of state relate the bulk concentration, surface concentration, and surface tension. At equilibrium, the surface concentration increases with the ionic strength of the electrolyte, so the surface tension reduces more strongly. The data at all ionic strengths are well described by the Davies model. Because the characteristic diffusion time scale increases as the square of the surface concentration, an increasing equilibration time with ionic strength might be anticipated for this molecule. However, the time required for the surface tension relaxation observed in experimen.
Misalignment effects on steady‐state and dynamic behaviour of compliant journal bearings lubricated with couple stress fluids

This work concerns the steady‐state and dynamic analysis of misaligned compliant journal bearings considering the effects of couple stresses arising from the lubricant blended with polymer additives. Based on the Stokes micro‐continuum theory, a modified form of the Reynolds equation is derived. The displacement field at the fluid film–bearing liner interface due to pressure forces is determined using the elastic thin liner model. The effects of the misalignment and the couple stress parameters on static and dynamic performances such as pressure distribution, load‐carrying capacity, power loss, side leakage flow, misalignment moment, critical mass and whirl frequency are presented and discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis, structure and applications of hypervalent organoantimony compounds having intramolecular E→Sb (E = N, O, S) coordinations

The review article covers the hypervalent organoantimony compounds that are with intramolecular N, O, S￻Sb coordinations synthesized in the past 20 years. We describe their structures and the related coordination chemistry, highlighting a number of hyperva- lent stibines. These compounds have shown many applications in organic synthesis. They are useful reagents for reactions such as cross- coupling and arylation with organic halides, and addition with carbonyl compounds. They can be used as Lewis acid catalysts in organic synthesis. Furthermore, they can be utilized as catalysts or reagents for CO2 chemical fixation. It is envisaged that more hypervalent or- ganoantimony compounds of novel structure will be synthesized and find new applications in the near future.
Systematic Investigation of Side‐Chain Branching Position Effect on Electron Carrier Mobility in Conjugated Polymers

Recently, polymer field‐effect transistors have gone through rapid development. Nevertheless, charge transport mechanism and structure‐property relationship are less understood. Here we use strong electron‐deficient benzodifurandione‐based poly(p‐phenylene vinylene) (BDPPV) as polymer backbone and develop six BDPPV‐based polymers (BDPPV‐C1 to C6) with various side‐chain branching positions to systematically study the side‐chain effect on device performance. All the polymers exhibited ambient‐stable n‐type transporting behaviors with the highest electron mobility of up to 1.40 cm2 V−1 s−1. The film morphologies and microstructures of all the six polymers were systematically investigated. Our results demonstrate that the interchain π–π stacking distance decreases as moving the branching position away from polymer backbones, and an unprecedentedly close π–π stacking distance down to 3.38 Å is obtained for BDPPV‐C4 to C6. Nonetheless, closer π–π stacking distance does not always correlate with higher electron mobility. Polymer crystallinity, thin film disorder, and polymer packing conformation, which all influenced by side‐chain branching position, are proved to show significant influence on device performance. Our study not only reveals that π–π stacking distance is not the decisive factor on carrier mobility in conjugated polymers but also demonstrates that side‐chain branching position engineering is a powerful strategy to modulate and balance these factors in conjugated polymers.
Effect of CH4 addition on excess electron mobility in liquid Kr

The mobility μ of excess electrons has been measured in liquid mixtures of Kr and CH4 as a function of the electric field up to E≈104 V/cm and of the CH4 concentration x up to x≈10%, at a temperature T≈125 K, fairly close to the normal boiling point of Kr (Tb≈120 K) [Nucl. Instrum. Methods Phys. Res. A 430, 277 (1997)]. We present here new data extending the previous set in the low E region. At small E, μ appears to be quite independent of x. CH4 impurities prove to be less efficient in enhancing momentum transfer than liquified rare gas impurities Kr and Xe in liquid Ar. The dependence of μ on E at higher strengths is complicated. On the one hand, the addition of CH4 extends the range of E in which μ is field independent, by efficiently thermalizing the electrons. On the other hand, at the highest field, the presence of the impurities accomplishes a large increase of the electron drift velocity with respect to the pure liquid (up to a factor of 7 for the highest x). Moreover, at intermediate values of E,.
The fractionation of Ca isotopes by sputtering

Using a double-spike, mass spectrometric technique, we have measured the absolute isotopic composition of Ca sputtered from several Ca minerals by normally incident, low energy, nitrogen beams (130 keV N^+ and 100 keV N^(+)_(2)). The precision in the ^(40)Ca/^(44)Ca ratio is 0.05% for samples as small as 10^(−7) g, corresponding to a resolution of possible mass dependent isotope fractionation effects of ∼0.01% per unit mass difference. In general, the material sputtered first was isotopically light by up to 2% in the isotopic ratio ^(40)Ca/^(44)Ca when compared with the measured isotopic composition of the target; as the bombardment progressed, the isotopic composition became less light and approached the initial composition of the target. We have demonstrated that, after prolonged bombardment, a surface layer develops on the target with a distinctly heavy isotopic composition; the thickness of the layer is a significant fraction of the range of the bombarding ions. Angular distributions of the sputtered material show that, throughout the bombardment, the material ejected back along the beam direction was isotopically light relative to the material ejected at oblique angles; the difference in the isotopic ratio ^(40)Ca/^(44)Ca over the angular range was ∼ 1.5%. This fractionation with angle of ejection persisted even when a quasi-steady state was reached after heavy bombardment, when the isotopic composition of the material averaged over angle had become essentially indistinguishable from that of the pristine target. These results indicate that sputtering produces isotope fractionation and that there is a marked angular dependence in the effects. This suggests that solar wind sputtering of the lunar surface may contribute to the isotopic and elemental enrichments observed for the surface layers of soil grains.
Alkali Metal Partitioning in Ash from Pulverized Coal Combustion

Abstract The relationship between the original form of sodium and potassium in coal and the ultimate fate of these metals was explored through experimentation in a 17kw laboratory downflow combustor. Composition analyses of size segregated samples of airbone ash at exhaust conditions for six different coals are reported. In all cases sodium was enriched in the small particle size range, and was shown both to form a sodium rich fume as well as an enriched surface layer around existing particles. The fraction of sodium appearing in the small particle size range, and therefore previously vaporized, could be correlated with the fraction of sodium that was acid soluble and inversely with the amount of silicon present in the parent coal. Increased temperature led to a decrease in the amount of sodium vaporized. For the coals examined, potassium was present primarily in the mineral form. Although the fraction of potassium vaporized could be positively correlated neither with total nor with acid soluble forms of .
The Crystal Structure of Perchlorato-bis(2,2′-bipyridine)copper(II) Perchlorate, [Cu(ClO4)(bipy)2]ClO4

The structure of bis(2,2′-bipyridine)copper(II) perchlorate, Cu(bipy)2(ClO4)2, has been determined from three-dimensional X-ray data collected by the photographic method. The compound forms triclinic crystals with a=7.44(1), b=14.93(1), c=15.32(1) A, α=136.3(0.1), β=103.7(0.1), γ=83.2(0.1)°, and Z=2 in the space group P\bar1. The structure was solved by the usual Patterson and Fourier techniques and was refined by the least-squares method to an R value of 0.134. The crystal is composed of an infinite chain of [Cu(ClO4)(bipy)2+]∞ and ClO4−; a perchlorate ion in the chain bridges two adjacent copper atoms through its two oxygen atoms. Roughly speaking, the coordination polyhedron around the copper atom is a tetragonally-distorted octahedron; the four nitrogen atoms of bipyridine molecules are arranged in a flattened tetrahedral manner (average Cu–N=1.99 A), the least-squares plane of these atoms making an equatorial plane, while the polar positions are occupied by the two oxygen atoms of perchlorate anions,.
Multi-angle spectroscopic extreme ultraviolet reflectometry for analysis of thin films and interfaces

Modern nanotechnology is constantly raising demands to quality and purity of thin films and interlayer interfaces. As thicknesses of employed layers decrease to single nanometers, traditional characterization tools are no longer able to satisfy throughput, precision or non-destructibility requirements. Extreme ultraviolet (EUV) and soft X-ray reflectometry has not only demonstrated the ability to detect sub-nm thickness variations but also was shown to be very sensitive to chemical composition changes. Since the laboratory radiation sources in this wavelength range often emit in a relatively broad spectral range, a spectroscopic EUV reflectometry has been developed with the added benefit of a rapid measuring time on the order of milliseconds to seconds. In this paper, the extension of the method to multi-angle measurements will be presented. It allows to reduce a number of fit parameters in the analysis model, making the method suitable for complex samples of unknown composition. First experimental examples for Si-based layer systems measured under grazing incidence angles between 2° and 15° will be demonstrated and discussed. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Studies of the Glyoxylate Bypass of Streptomyces coelicolor A3(2)

In this study, molecular cloning of the structural gene encoding malate synthase (aceB) from Streptomyces coelicolor was attempted using two different approaches. Despite identification of potential sequences using genetic fingerprinting and southern hybridisation techniques, all my attempts to clone the full coding sequence of the gene were unsuccessful. Analysis of DNA sequences upstream of the structural gene encoding isocitrate lyase (aceA), led to the identification of potential open reading frame (pORF) which shows a very close similarity to pORF from Mycobacterium tuberculosis. The function of such an ORF in both organisms remains to be discovered.
The use of moment index displacement in analyzing fluorescence time‐decay data

Moment index displacement automatically corrects a number of significant nonrandom instrumental errors in fluorescence time‐decay measurements. Three‐component data, obtained by measuring the fluorescence decay of three different species mixed in the same solution, were used as a test sample. It was shown, as predicted by theory, that moment index displacement corrects three nonrandom instrumental errors: (1) the presence of scatter in the data; (2) time origin shifts between lamp and fluorescence data; and (3) lamp drift, or time‐dependent changes in the shape of the excitation curve. The data clearly show that the use of the method of moments with moment index displacement to analyze fluorescence decay data is not a curve‐fitting procedure. This procedure will accurately obtain decay parameters for multiple‐exponential decays from certain badly distorted data, yielding a calculated curve very different from the actual data.
Room temperature ferrimagnetic thin films of the magnetoelectric Ga2−xFexO3

(0k0) oriented films of the magnetoelectric material Ga2−xFexO3 (0.8 ≤ x ≤ 1.4) have been grown by pulsed laser deposition on various substrates: the non conducting yttrium stabilized zirconia (YSZ) (001) and the conducting indium tin oxide (ITO) buffered YSZ(001) and single crystalline Pt(111) buffered YSZ(111). The films are ferrimagnetic for all compositions and their Curie temperature increases with x. For x = 1.4, their Curie temperature is above room temperature (370 K) and their room temperature saturation magnetization is 90 emu/cm3. The effect of the conducting substrates on both the crystalline and electrical properties of the films has been studied. The single crystalline Pt(111) buffered YSZ(111) substrates allow substantial improvements both on the crystallographic and electrical points of view with a reduction of the number of in-plane variants down to 3 and a decrease of the leakage current down to 10−5 A at 10 V. This work opens new perspectives for the integration of a room temperature ferrimagnetic magnetoelectric material in spintronic devices.
Influence of silver clusters on the light absorption in CdBr 2 -Ag crystals

Experimental studies of the absorption spectra of CdBr2-Ag photochromic crystals revealed several absorption bands positioned close to the intrinsic absorption edge. It is suggested that impurity silver ions, neutral silver atoms and intrinsic lattice defects form nanoclusters which are responsible for the absorption peaks within the transparency range of the crystal. The effect of UV radiation on the absorption profile is also discussed in the framework of the proposed model.
Molecular transport in a nonequilibrium droplet microemulsion system.

In this paper, we consider the problem of oil molecular transport between nonequilibrium microemulsion oil droplets in water. In particular, we have investigated the kinetics of solubilization of big oil drops by smaller microemulsion droplets transforming a bimodal size distribution into an equilibrium microemulsion with a unimodal size distribution. The process involves the diffusion of oil monomers across the aqueous solvent. Solubilization experiments are presented on a well-characterized nonionic microemulsion system, where interfacial area and dispersed volume are conserved and where the excess oil chemical potential is dominated by interfacial curvature energy. An analysis of the experiments shows that the solubilization kinetics depend significantly on the concentrations and sizes of big and small droplets. We formulate a quantitative model for the solubilization kinetics where the effects of size and concentrations are treated within the framework of a cell model. A quantitative agreement between model and experiment is obtained, and the analysis also shows that the majority of oil monomers are captured by small droplets already in the vicinity of the big drop surface when the concentration of small droplets is high.
Novel phosphors based on porous materials

Technological conditions have been developed for the preparation of nanocomposite phosphors based on porous InP, GaP and GaAs semiconductor as well as Al2O3 and TiO2 dielectric templates doped with rare earth and transition metal ions. Semiconductor and dielectric templates are prepared by electrochemical treatment of bulk semiconductor substrates and metallic plates, respectively. Doping is performed by impregnation from liquid solutions followed by thermal treatment. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Bis(5-bromo-N-cyclo­hexyl­salicyl­idene­aminato)­nickel(II): an orthorhombic polymorph

The title compound, [Ni(C13H15BrNO)2], crystallizes in the orthorhombic space group Pbca, rather than the previously reported monoclinic space group C2/c [Sun & Ng (2005). Acta Cryst. E61, m323–m324]. The NiII atom is coordinated by two N atoms and two O atoms from two Schiff bases, forming a distorted tetrahedral geometry.
Essential oil composition and antioxidant activity of leaves and flowers of Skimmia anquetilia N.P. Taylor & Airy Shaw

The essential oils of the leaves and flowers of Skimmia anquetilia N.P.Taylor & Airy Shaw (family: Rutaceae) were examined by the combination of gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The analysis of the oils from leaves and flowers revealed the presence of β-phellandrene (1.8%, 18.4%), geijerene (2.0%, 15.0%), germacrene B (11.6%, 2.0%), linalyl acetate (7.3%, 11.2%), linalool (9.5%, 9.4%), α-terpineol (5.6%, 4.4%) and pregeijerene (0.2%, 5.6%) as major constituents. The antioxidant activity of the leaf and flower oils was studied and compared by different methods including their effect on reducing power, chelating properties of Fe+2 and in vitro 2’2’-diphenylpicrylhadrazyl (DPPH) radical-scavenging activity. The total phenolic contents in the water extracts of leaf and flower were estimated and compared.
Crystal structure of lithium disulfate, Li2[S2O7], Li2O7S2

Abstract Li2O7S2, orthorhombic, Pnma (no. 62), a = 13.177(2) Å, b = 8.2516(7) Å, c = 4.8547(4) Å, V = 527.8 Å3, Z = 4, Rgt(F) = 0.0338, wRref(F2) = 0.1054, T = 153 K.