Miracle-dz/UniFAR-FTUs huggingface dataset:
Highly electrically conductive rGO/PVA composites with a network dispersive nanostructure

Graphene oxide (GO)/polyvinyl alcohol (PVA) composites were prepared and thoroughly characterized. Through a convenient effective method, uniformly dispersed reduced graphene oxide (rGO)/PVA composites could be obtained by swelling the PVA matrix with a reductant solution. The electrical conductivity of the composite increases with increasing rGO content, while there is a sharp increase for the rGO content beyond 10 wt%. Such an increase was evidenced by the formation of an rGO network so as to diminish the electrical resistance by the interconnection structure of rGO. In our studies, the conductivity of the rGO/PVA film increases from 6.04 × 10−3 S m−1 to 5.92 S m−1 as the rGO content increases from 4 wt% to 14 wt%.
Central nervous system effects of the essential oil of the leaves of Alpinia zerumbet in mice

Objectives Alpinia zerumbet, known in Brazil as colônia, is popularly used as a diuretic, antihypertensive, anti‐ulcerogenic and sedative. Based on this, we have investigated the central effects of the essential oil isolated from A. zerumbet leaves.
Computation of TSDC Peak Parameters in Amorphous Polymers using Vogel‐Tammann‐Fulcher Relaxation Model

We have modified the thermally stimulated depolarization current (TSDC) theory so that it contains the relaxation obeying the Vogel‐Tammann‐Fulcher relaxation model. Thermal sampling (TS) technique was used to decompose the complex TSDC spectrum to a number of elementrary peaks. Numerical method is applied for the analysis of TS spectra for the amorphous polar poly(vinyl chloride‐co‐vinyl acetate‐co‐2‐hydroxypropyl acrylate) (PHHV); poly(methyl methacrylate) (PMMA), and poly(vinyl chloride) (PVC). The characteristic alpha‐relaxation peak parameters, namely the pre‐exponential factor (τ0) and its related Vogel‐Tammann‐Fulcher (VTF) energy (EVTF), for each thermal windowing (TW) experiment were determined. The almost temperature independence of the peak parameters suggests that this behavior is a result of segmental dipole relaxation, and consequently, there is no distribution in both peak parameters.
Macromolecular design via réversible addition-fragmentation chain transfer (RAFT)/Xanthates (MADIX) polymerization

Among the living radical polymerization techniques, reversible addition–fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations appear to be the most versatile processes in terms of the reaction conditions, the variety of monomers for which polymerization can be controlled, tolerance to functionalities, and the range of polymeric architectures that can be produced. This review highlights the progress made in RAFT/MADIX polymerization since the first report in 1998. It addresses, in turn, the mechanism and kinetics of the process, examines the various components of the system, including the synthesis paths of the thiocarbonyl-thio compounds used as chain-transfer agents, and the conditions of polymerization, and gives an account of the wide range of monomers that have been successfully polymerized to date, as well as the various polymeric architectures that have been produced. In the last section, this review describes the future challenges that the process will face and shows its opening to a wider scientific community as a synthetic tool for the production of functional macromolecules and materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:5347–5393, 2005
Free energy disconnectivity graphs: Application to peptide models

Disconnectivity graphs are widely used for understanding the multidimensional potential energy surfaces (PES) of complex systems. Since entropic contributions to the free energy can be important, particularly for polypeptide chains and other polymers, conclusions concerning the equilibrium properties and kinetics of the system based on potential energy disconnectivity graphs (PE DG) can be misleading. We present an approach for constructing free energy surfaces (FES) and free energy disconnectivity graphs (FE DG) and give examples of their applications to peptides. They show that the FES and FE DG can differ significantly from the PES and PE DG.
Distribution of Selenium in Bovine Milk and Selenium Deficiency in Rats Fed Casein-based Diets, Monitored by Lipid Peroxide Level and Glutathione Peroxidase Activity

A major proportion of selenium in bovine milk was found in fluorometric analysis to be associated with the casein fraction, largely in alkali-labile form, and the rest with the whey fraction mostly in free selenite form. This uneven distribution of milk selenium seems to provide an explanation for selenium deficiency in purified caseins. The activity of glutathione peroxidase, a selenoprotein, in the liver of growing male rats fed ad libitum low-selenium diets containing either vitamin-free casein or Torula yeast 0.065 ± 0.012 or 0.015 ± 0.004 μ g Se/g diet, respectively) for 3 weeks decreased to 4 to 6% of that of the control rats fed a commercial stock diet (0.185 ± 0.092 μ g Se/g diet). Selenium status was evaluated by three different parameters for the rats assigned under pair-feeding regimen to those vitamin-free casein-based diets which were supplemented with graded levels of selenium as sodium selenite. The hepatic levels of the thiobarbituric acid-reactive substance, an indication of lipid peroxid.
A high‐throughput method to measure photosynthesis‐irradiance curves of phytoplankton

Photosynthesis‐irradiance (P‐E) curves are an important tool used to characterize the physiology of phytoplankton. In most marine environments, low biomass and photosynthetic rates make the carbon‐14 tracer technique, used in conjunction with photosynthetrons to create the light gradient, the method of choice to measure P‐E curves. However, conventional photosynthetrons are bulky and require large chilled‐water recirculators to maintain temperature. In addition, setting the light levels is difficult. Here we describe a new type of photosynthetron, the microphotosynthetron, which avoids these problems. The microphotosynthetron is based on the standard 96‐well plate format and allows precise light control using tunable light‐emitting diodes (LEDs). Temperature is regulated using a Peltier device. Using monotypic cultures of several phytoplankton strains grown at different light levels and mixed field populations from different sampling sites and depths, we evaluated the utility of the microphotosynthetron by comparing the measured P‐E curves to curves from standard photosynthetrons. The microphotosynthetron P‐E curves were identical in initial slope (α) (P > 0.1) and light‐saturated photosynthesis (Pmax) (P > 0.1) to P‐E curves measured using conventional photosynthetrons. In addition, because the microphotosynthetron is based on a standard 96‐well plate format, set‐up and processing is greatly expedited in comparison to the conventional photosynthetron technique. Although the microphotosynthetron utilizes smaller sample volumes (200 µL) and therefore might not be suitable for highly heterogeneous samples, it has numerous advantages over the conventional protocol. We recommend the microphotosynthetron approach to measure P‐E curves as a method for the rapid screening of photophysiological properties of phytoplankton, in particular, monotypic cultures.
Magnetic hyperfine interactions in the electronic spectra of diatomic molecules I. The rotational structure of absorption bands of gaseous BiO

The absorption spectrum of gaseous BiO has been photographed at a resolution of about 300000. The ground state X1, is the Ω = 1/2 component of a 2 π state in which the spin-orbit coupling must be very large, ~ 1 eV. The doubling in X1 is large, and for v = 0, ∆vcd ~ 0.187 (J + 1/2). Structure of 16 bands has been analysed: the bands arise from transitions from X1 to four states, A 2π1/2, B(4Ʃ-) Ω = 1/2, C(2∆3/2) Ω = 3/2 and D(2π1/2) Ω = 1/2. They show a number of unusual features, not least of which is the fact that, with the exception of D─X1, the lines in the regions analysed, 251/2 ≼ J ≼ 90 1/2, have a half-width, ∆v1/2 ~ 0.25 cm-1, apparently independent of J, and far larger than the Doppler width. It is shown that this effect arises from unresolved nuclear magnetic hyperfine doubling of the levels in the ground state. The rotational levels in the single level of state D to be observed are predissociated both at high and at low J, but for intermediate values comparatively sharp lines are observed, by a partial cancellation of the h. f. s. between states D and X1. The case b designation of state B is 4Ʃ-, but the structure of the bands show that the transition is better described as Ω = 1/2 — Ω = 1/2, in which the perpendicular transition moment is somewhat larger than the parallel one.
Diaquabis(4-amino-3-methyl-4,5-dihydro-1H-1,2,4-triazole-5-thione)nickel(II) nitrate : a sulfur-nitrogen chelate

The title compound, [Ni(C 3 H 6 N 4 S) 2 (H 2 O) 2 ](NO 3 ) 2 , is an octahedral complex of nickel(II) in which two triazole ligands are coordinated in a bidentate fashion through the amine and thione substituents. The coordination sphere has the two S atoms trans with respect to each other, while the N atoms and two water molecules are ligated in cis positions. The Ni-S and Ni-N bond lengths in the chelate are consistent with those in similar octahedral nickel complexes. The geometry of the complexed triazole moiety is not substantially different from that of the free molecule.
Chemical characterisation of extract derived from Daphne papyraceae and sonicator dyeing of cotton, silk and wool with the extract

Purpose – The purpose of this paper is to evaluate the efficiency of ultrasonication on new natural dye obtained from leaves and stem extracts of Daphne papyraceae using metal mordant for good cotton, silk and wool dyeing prospects. It also proposes to effect the characterisation of the colorant.Design/methodology/approach – For effective natural dyeing with leaves and stem extracts of D. papyraceae, both conventional and sonication methods for cotton, silk and wool dyeing were carried out using metal mordants. The purpose of using sonication was for betterment of dye uptake, improved dye adherence and good wash and light fastnesses. Results show marked improvement by the chosen dyeing method. Simultaneously, chemical characterisation of the colorant was carried out by first column chromatographic separation of the crude extract, followed by spectral analysis of the isolated products.Findings – The superiority of sonicator dyeing over conventional dyeing in terms of enhanced resource productivity and, as .
Transport properties in a family of dialkylimidazolium ionic liquids

The transport properties of 1,3-methylalkylimidazolium based ionic liquids are sensitive to their chemical structure. In this work, two key features of the chemical structure were investigated: the role of the anion and the length of the alkyl chain. Four different anions were examined for the 1,3-methylethylimidazolium salt (MeEtImX): bromide (Br−), iodide (I−), trifluoromethanesulfonate (Tf−) and bis(trifluoromethanesulfonyl)amide (NTf2−) anions. Increasing the size of the anion resulted in a decrease of the melting point and a slight increase in the cation diffusion coefficient. The differences in cation diffusion behaviour reflect the differences in viscosity, with much higher viscosities expected for the halide salts. In contrast to this diffusion behaviour, the melt conductivities are all very similar. The inconsistency between the calculated conductivity (based on diffusion measurements) and the conductivity measured, however, is attributed to correlated ion motions and/or the diffusion of neutral species that do not contribute to the conductivity. The effect of the length of the alkyl substituent was also studied for 1,3-methylalkylimidazolium iodide (MeRImI). Increasing the length of the alkyl chain, from methyl to a linear heptyl chain, suppresses the melting point and decreases both the conductivity and cation diffusion coefficients. In this case, the viscosity, as well as the size of the cation, influence ion transport in these materials.
Determination of Polyethylene Glycol Monoester Acrylate and Polyethylene Glycol Diester Acrylate Using Reversed-Phase High-Performance Liquid Chromatography

A procedure was developed for the determination of polyethylene glycol monoester acrylate (PEGMA) and polyethylene glycol diester acrylate (PEGDA) by reversed-phase high performance liquid chromatographic (RP-HPLC) with UV detector. Sample was well separated on an SinoChrom ODS-BP (C-18) column (200 × 4.6 mm i.d., 5 μm) with mobile phases composed of acetonitrile-phosphate buffer solution (0.05 mol · L−1 pH = 6.86) in the ratio of 42:58 (v/v). The PEGMA and PEGDA were detected by UV detector at 205 nm, and quantitatively analyzed with an external standard of methyl acrylate. For PEGMA, the linear response ranged from 0.40 × 10−5 mol · L−1 to 2.00 × 10−3mol · L−1 (r2 > 0.999), the detection limit was 0.12 × 10−5 mol · L−1, the recovery rate was found to be 93.4%–99.7%. For PEGDA, the linear response ranged from 0.20 × 10−5 mol · L−1 to 1.00 × 10−3mol · L−1 (r2 > 0.999), the detection limit was 0.04 × 10−5 mol · L−1, the recovery rate was found to be 99.1% ∼ 105.8%. This quantitative method can also be used in the HPLC analysis of other α,β-unsaturated esters.
Chemical factors influencing colloid-facilitated transport of contaminants in porous media

The effects of colloids on the transport of two strongly sorbing solutesa hydrophobic organic compound, phenanthrene, and a metal ion, Ni2+were studied in sand-packed laboratory columns under different pH and ionic strength conditions. Two types of column experiments were performed as follows: (i) sorption/mobilization experiments where the contaminant was first sorbed in the column under conditions where no colloids were released and mobilized under conditions where colloids were released as a result of ionic strength reduction in the influent; and (ii) transport experiments where the contaminant, dissolved or sorbed on colloids, was injected into columns packed with a strongly sorbing porous medium. In the first type of experiment, contaminant mobilization was significant only when all releasable colloids were flushed from the column. In all other cases, although high colloid particle concentrations were encountered, there was no marked effect on total contaminant concentrations. In the second type of .
Drude‐Model Calculation of Dispersion Forces. II. The Linear Lattice

The London‐van der Waals cohesive energy of a linear lattice is calculated in the dipole‐dipole approximation, including all orders of perturbation. This result is obtained by applying the Born‐von Karman method to the electronic motions, using a model which represents each molecule as an isotropic harmonic dipole‐oscillator. The dispersion interaction energy of the lattice is expanded in powers of the parameter α/a3 (where α is the molecular polarizability and a the nearest neighbor distance), and is computed up to the eighth order. For values of α/a3 appropriate to actual molecular crystals, the main contribution to the energy comes from the second order. Among the higher order terms, the third order is always important, but for α/a3≥0.06, contributes less than one‐half of the total correction to the second‐order energy.
A profile refinement method for nuclear and magnetic structures

A structure refinement method is described which does not use integrated neutron powder intensities, single or overlapping, but employs directly the profile intensities obtained from step-scanning measurements of the powder diagram. Nuclear as well as magnetic structures can be refined, the latter only when their magnetic unit cell is equal to, or a multiple of, the nuclear cell. The least-squares refinement procedure allows, with a simple code, the introduction of linear or quadratic constraints between the parameters.
Oxo-Bridged Trinuclear Fe(III) Complexes: Structural and Magnetic Properties

The crystal structure of (µ3-Oxo)-hexakis(µ2-cyanoacetato)-triaqua-tri-iron(III) nitrate pentahydrate shows that the trinuclear ferric complex has an equilateral molecular structure which is manifested in the 57Fe Mössbauer spectrum single doublet. The magnetic measurements reveal antiferromagnetic exchange interactions of –22.85 cm-1, between the metal centers, that compel the system to a total spin ground state of S = ½.
Gold colloidals optical characterization by observing their scattering polarization

Polarized light scattering is utilized to measure the optical anisotropy and the aspect ratio for nearly spherical colloidal gold nanoparticles as well as to observe their rotational dynamics which were detected as fluctuations in the time-trace of the scattering polarization. A comparison between the measured distributions of maximum anisotropy and aspect ratio with those distributions calculated based on the TEM images analysis are found to show an excellent agreement confirming the validity of our approach. Our method has the advantage to be simple, easy to implement, and can yield access to different projections of the particle due to its rotational diffusion. The range of aspect ratios for the sample being studied is 1 ~ 1.3 and another results for rods with aspect ratio of 2.4 is discussed. Gold nanoparticles have a good biocompatibility where the possibility of conjugation to a variety of biomolecules and antibodies make them suitable for optical imaging and optical probes which can be used for nanoscale orientaional sensing to monitor orientations and rotations of biomolecules during their functional task.
Thin‐Layer Chromatography‐Direct Bioautography of Flumequine Residues in Milk

Abstract Fluoroquinolone antibiotics are a relatively new group of synthetic antibiotics derived from 3‐quinolone carboxylic acid. They are widely used in both human and veterinary medicine. Flumequine is frequently used in fish, poultry, and cattle husbandry for the treatment and prevention of diseases. It is also used to enhance weight gain of livestock as a feed or water additive. Hence, the antibiotic residues may be present in edible products, e.g., in meat, eggs, or milk. Thin‐layer chromatography–direct bioautography combines TLC with microbiological detection. In the present paper, conditions for bioautographic detection of flumequine were determined for the antibiotic standards. The established method was applied for semi‐quantitative determination of flumequine residues in milk. Matrix solid‐phase dispersion was used as a pre‐separation method.
THE GAS–LIQUID PARTITION CHROMATOGRAPHY OF CARBOHYDRATE DERIVATIVES: PART III. THE SEPARATION OF AMINO GLYCOSE DERIVATIVES AND OF CARBOHYDRATE ACETAL AND KETAL DERIVATIVES

Gas–liquid partition chromatography has been used to separate the anomeric acetates of 2-amino-2-deoxy-D-glucopyranose (D-glucosamine) and of 2-amino-2-deoxy-D-galactopyranose (D-galactosamine) and also their fully acetylated reduction products, 2-acetamido-2-deoxy-1,3,4,5,6-penta-O-acetyl-D-glucitol and 2-acetamido-2-deoxy-1,3,4,5,6-penta-O-acetyl-D-galactitol. The gas–liquid partition chromatographic method has also been successfully applied to the separation of unsubstituted carbohydrate acetal and ketal derivatives and to those derivatives in which the free hydroxyl groups have been substituted by O-acetyl, O-benzoyl, O-benzyl, carbonate, O-methanesulphonyl, O-methyl, and O-toluene-p-sulphonyl groups.
Monostabilization of Surface-Stabilized Ferroelectric Liquid Crystal Using Polymer Stabilization

Surface-stabilized ferroelectric liquid crystals (SSFLCs) fabricated by adopting polymer stabilization in terms of the UV photocure of doped photocurable monoacrylates with mesogenic side chains at a temperature where the LC medium is in the SmC* phase under the simultaneous application of a monopolar electric field, exhibit monostable electrooptical characteristics with grayscale capability without threshold. We suggest a model for explaining the monostability of this polymer-stabilized SSFLC by investigating theoretically the free energy of the SSFLC before and after the photocure.
Determining the stable isotope ratio of total dissolved inorganic carbon in lake water by GC/C/IIRMS

A simple, precise method for determining the carbon stable isotope ratio of total dissolved inorganic C (ΣCO 2 ) in freshwater samples is described. Water samples are packed in airtight glass bottles of known inner volume (∼70 ml) with no air bubbles. Subsequently, a headspace of 5.0 ml is created inside each bottle with pure helium gas, and each sample is acidified by adding 0.5 ml of a CO 2 -free, 6.0 N HCI solution. After the original dissolved CO 2 has equilibrated with the headspace gas, a portion of this headspace gas is subsampled and injected into the GC/C/IRMS (gas chromatograph/combustion furnace/isotoperatio mass spectrometer) system to determine the carbon isotope ratio of the CO 2 . The isotope ratio of CO 2 remaining in the liquid phase is calculated by temperature-dependent isotope discrimination between gas and aqueous phases. The isotope ratio of ΣCO 2 of the original sample is then derived assuming isotope mass balance. The analytical precision of this method is ±0.l‰. The method enables a single operator to determine the isotopic ratio in at least 60 lake-water samples within 3 d of sampling.
Influence of polar substituents on the mesomorphism of non-symmetrical achiral four-ring bent-core compounds: synthesis and characterisation

The synthesis and characterisation of stable achiral asymmetrical four-ring banana-shaped molecules are presented. These consist of a laterally fluoro-substituted 3,4ʹ-disubstituted biphenyl unit with an ester linkage between the phenyl rings as the central unit in 4-(N-4ʹ-n-alkyloxysalicylidene)aminophenyl [2-fluoro-5-(N-4ʹ-n-alkyloxy-salicylidene) amino-benzoate]. These compounds are thermally and hydrolytically stable due to inter- or intramolecular hydrogen bonding and exhibit columnar (B1) phases. The phases have been characterised by thermal microscopy and differential scanning calorimetry. A representative example has also been characterised by X-ray diffraction.
LARGE EDDY SIMULATION OF A SMALL POOL FIRE

Large eddy simulation has been applied to the prediction of a small pool fire experimentally tested by Venkatesh et al. The Smagorinsky's eddy viscosity model is used for subgrid-scale (SGS) turbulence closure and a modified laminar flamelet model (MLFM) based on the Cook and Riley approach is used for SGS combustion modeling. The predictions have captured the unique characteristics of small pool fires such as flame anchoring and double flame, as shown in previous theoretical analysis and experiments. The existence of the premixed zone of fuel and air, which is thought to be the reason for flame anchoring, is evidenced by the low gradient of temperature and mixture fraction near the burner rim. The experimentally observed double flame can be seen from both the predicted temperature contour and velocity vectors. For the mean temperature field where experimental data are available for quantitative comparison, the predictions with the MLFM are found to be in very good agreement with the data. In line with general expectations, the study also reveals that the predicted small pool fire is nearly axially symmetric. Comparison of the predictions with the two different SGS combustion models have highlighted the importance of SGS combustion modeling in capturing the fine details of such small pool fires. Considerable discrepancies have been found in the predictions of the velocity and temperature fields, and the predictions of the mixture fraction model indicate a slightly higher and more centered premixed flame near the burner rim.