Miracle-dz/UniFAR-FTUs huggingface dataset:
Strategies for Enhancing Expansion in Starch-Based Microcellular Foams Produced by Supercritical Fluid Extrusion

Supercritical fluid extrusion (SCFX) is a recent technological development for production of expanded starch-based foams in which formation of a microcellular structure is achieved by injection of supercritical CO2 into the melt. The high effective diffusivity of CO2 in the porous matrix favors escape of the gas to the environment, reducing the amount available for diffusion into the bubbles, thus posing an important challenge. This study utilized two approaches to address this problem: (a) increasing the nucleation rate and thus the final bubble density in the foam, and (b) reducing the melt temperature. The former was achieved by decreasing the nozzle diameter in order to achieve a higher pressure drop rate as the starch-CO2 melt flows through the nozzle. The second approach was evaluated by introducing a cooling zone prior to the entry of the melt into the nozzle. Bubble density increased more than fourfold when the nozzle radius was decreased from 3.00 to 1.50 mm. A higher bubble density led to a greater barrier or resistance to diffusion of CO2 to the environment, and increased expansion ratio by as much as 160%. Cooling of the melt resulted in a decrease in diffusion coefficient of CO2 in the starch melt, and thus reduced CO2 loss to the environment. The expansion ratio increased by 34% as the melt temperature decreased from 60 to 40°C. The above-mentioned strategies can be useful in controlling and enhancing expansion, which ultimately determines the textural attributes of the expanded food product.
Kinetic Study of Sorption of 2,4‐D and Atrazine on Rubber Granules

For the removal of 2,4‐D (2,4‐dichloro‐phenoxy‐acetic acid) and atrazine (2‐chloro‐4‐ethyalamino‐6‐isopropylamino‐s‐traiazine) from water environment, batch studies were performed to study the kinetics of 2,4‐D and atrazine sorption by rubber granules. Experiments were conducted at various initial concentrations of 7.5 mg/L, 4 mg/L, and 0.5 mg/L of 2,4‐D and atrazine with 18 g/L sorbent dose. The equilibrium time was found to be 120 minutes for both 2,4‐D and atrazine. The regression analysis for the experimental data showed that the rapid stage zone of kinetics profiles followed a first order reversible kinetics for all initial concentrations of sorbate. The various thermodynamic properties such as enthalpy and entropy activation values (ΔH and ΔS) also show that the sorption is spontaneous. This article will provide information toward understanding the sorption phenomena of 2, 4‐D and atrazine on waste tyre rubber granules. It also is valuable to us in finding out the rate constant of sorption of 2,4‐D and atrazine.
Quantitative analysis of polymorphic mixtures of carbamazepine by Raman spectroscopy and principal components analysis

The polymorphic behaviour of drugs is a major concern of the pharmaceutical industry as it may have considerable formulation, therapeutic, legal and commercial implications. It is therefore crucial to be able adequately to identify and quantify different polymorphic forms of drugs as early as possible in the drug discovery and development process. The aim of the present study was to investigate the application of Raman spectroscopy and principal components analysis (PCA) to the quantitative analysis of polymorphic mixtures of carbamazepine forms III and I, based on both individual peak areas and heights in the Raman spectra and whole wavenumber ranges. Various linear regressions indicated that in general using every fourth wavenumber value of a larger region of the Raman spectrum gives better quantitative results than choosing defined peak areas and peak heights, as the spectral differences between the polymorphs were only subtle. Baseline correction of the spectral data did not appear to improve the quantitative analysis, with detection and quantification limits being the lowest (0.33 and 1.09%, respectively) and R2 being the highest (0.96) when using every fourth wavenumber value from 2950 to 3100 cm−1 as input data for the PCA analysis without baseline correction. This study demonstrated that PCA of Raman spectroscopic data provides a sensitive method for the quantitative analysis of polymorphic forms, with a quantitation limit of <2%, if the spectral input data are selected carefully. In the absence of clear and distinct spectral differences at certain wavenumbers between the polymorphic forms, selection of larger spectral regions that contain most of the detectable differences between the two forms appears to be the best data selection technique. Copyright © 2004 John Wiley & Sons, Ltd.
A Review on Synthesis and Characterization of Nanostructured Conducting Polymers (NSCP) and Application in Biosensors

The development of nanostructured conducting polymers has opened up novel fundamental and applied frontiers. The present article reviews recent works dealing with synthesis, characterization of nanostructured conducting polymers, and their applications related to biosensors. Various synthesis strategies, mechanism and process parameters, along with their characterization techniques are discussed. Some potential areas for biosensor related applications of nanostructured conducting polymers are highlighted, including catalytic biosensors and bioaffinity biosensors.
Dynamic surface tension in concentrated solutions of CnEm Surfactants:A comparison between the theory and experiment

Dynamic surface tension (DST) measurements have been carried out with a series of CnE6-type surfactants with varying alkyl chain length (n = 10−16). Major emphasis has been placed on the DST relaxation in complex solutions containing both the micellar and monomer forms of surfactant. This paper also provides a step-by-step guidance to the theoretical interpretation of DST data for micellar solutions. Distributions of monomers and micelles in the vicinity of the gas/liquid interface, adsorption kinetics, and DST relaxation curves have been simulated in the framework of the Fainerman theory (Fainerman, V. B. Kolloid Z. 1981, 43, 94) explicitly allowing for monomer/micelle interconversation. A thorough numerical analysis has shown that although the Fainerman theory can follow the general experimental trends, it clearly lacks the flexibility needed to provide a self-consistent and quantitatively correct description of the process. Possible reasons for this disagreement are discussed.
Alkaline hydrolysis of ethyl acrylate–acrylonitrile–divinylbenzene copolymer beads†

This article deals with the alkaline hydrolysis of ethyl acrylate–acrylonitrile–divinylbenzene copolymer beads. Chemical changes during hydrolysis were evaluated by means of determination of total weight exchange capacity and of infrared spectroscopy. The influence of reaction temperature, concentration of the hydrolytic agent, degree of copolymers crosslinking as well as the influence of particle size upon the rate of hydrolysis were studied as a function of time. The mathematical and statistical calculations of experimental data were carried out. With respect to time dependence of hydrolysis of the copolymer functional groups, the average values of reaction rate constants as well as the values of assumed diffusion coefficients were calculated. The analysis is based on partial linearization of experimental results by means of semilogarithmic transformation. The empirical relations expressing dependences of reaction rate constants and of diffusion coefficients on conditions of hydrolysis were determined.
Electrical conductivity optimization in electrolyte-free fuel cells by single-component Ce0.8Sm0.2O2-δ–Li0.15Ni0.45Zn0.4 layer

Single-component electrolyte-free fuel cells possess a similar function to the traditional fuel cells with a complex three-component structure. However, how to enhance their electrical properties for practical industrial applications remains a timely and important issue. Here, we report the manipulation of concentration ratios of ionic to electronic conductors in an electrolyte-free Ce0.8Sm0. 2O2-δ–Li0.15Ni0. 45Zn0.4 by adjusting the relative weight between its two inside compositions. Our systematic investigations reveal that the fuel cell with 30% in weight of Li0.15Ni0. 45Zn0.4 exhibits an almost uniform distribution of the two compositions and has a total conductivity as high as 10 × 10−2 S cm−1 at 600 °C. Such an enhancement is found to be attributed to the established balance between the numbers of its inside ionic and electronic conductors. These findings are relevant for the technological improvement of this new species of electrolyte-free fuel cell and represent an important step toward commercialization of this single-component fuel cell.
High‐Order Supersatellite Reflections in Labradorite. A SynchrotronX‐ray Diffraction Study

The supersatellite reflections in the feldspar mineral labradorite are related to the Boggild intergrowth, a lamellar structure with a periodicity of about 1500/~. With high-resolution X-ray diffraction using synchrotron radiation, supersatellites up to fourth order are observed. The system is an example for a natural superstructure with high-order diffraction harmonics. The satellite intensities reflect a transverse displacement modulation with a large amplitude. The complete unit cell of labradorite is affected by the displacement. In this context, various possible displacement functions are discussed. A Fourier expansion of the displacement function that yields the best agreement between measurement and theory has nearly triangular shape. The line width of the satellites characterizes imperfections of the lamellar superstructure: It increases linearly with satellite order, which is ascribed to uncorrelated variations (FWHM = 480/~) of the lamellar thickness. Labradorite crystals often show a colourful iridescence arising from a lamellar structure, the BCggild intergrowth (BCggild, 1924), with periodicities of around 1500/~. The satellite reflections related to this superstructure are the subject of the present study. They were first observed by Jagodzinski & Korekawa (1965) and called s-satellites (supersatellites) by them. Burandt, Komorek, Press & Boysen (1992) gave a first quantitative analysis of the satellite intensities: They were analysed within a model of a harmonic transverse displacement modulation of the entire unit cell, accompanied by a harmonic density modulation. A displacement amplitude of 0.75/~ was obtained. Therefore, this modulation has been called a 'frozen-in' transverse acoustic (TA) phonon. The contribution of the density modulation to the intensities turned out to be less than 2% of the unmodulated structure factor and hence is insignificant. This investigation was based on a relatively small data set of 25 a-reflections (see below for definition) and their satellites collected at a laboratory X-ray diffract©meter and the data were restricted to only two different scattering planes. The limited amount of data was due to the
Open spaces in the subsurface region of polyethylene probed by monoenergetic positron beams

Open spaces in the subsurface region (<10 μm) of very low density polyethylene were probed by a monoenergetic positron beam. From measurements of Doppler broadening spectra measurements of the annihilation radiation and the lifetime spectra of positrons as a function of incident positron energy, the size of the open spaces in the region of 0–3 μm was found to be larger than that in the deeper region. This was attributed to the cooperative motion of large segments of molecules which is activated near the surface. After the freezing in of such motions (below 230 K), although the lineshape parameter S in the bulk was almost constant, S in the region of 0–3 μm decreased with decreasing temperature. This discrepancy was associated with the presence of the open spaces with an excess content and the resultant contraction of amorphous structure near the surface. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. B Polym. Phys. 36: 2597–2605, 1998
Monodispersed Molecularly Imprinted Polymer Beads with Enhanced Atrazine Retention Ability Synthesized with Polymeric Diluents

Molecular imprinting technique was applied for the preparation of polymer beads selected for a triazine herbicide, atrazine. Polystyrene, poly(methyl methacrylate) and poly(ethylene glycol) were examined as polymeric diluents, and the morphology of the resultant molecularly imprinted polymers was investigated by scanning electron microscopy. Among the examined polymeric diluents, styrene was shown to be favorable for obtaining monodispersed spherical polymer with high retention ability for atrazine.
Application of direct thermal liquefaction for the conversion of cellulosic biomass

Direct thermochemical conversion of cellulosic biomass to useful products has been studied as an alternative to conventional biological processes. At temperatures of 250-400 C and pressures up to 20.7 MPa in the presence of sodium carbonate, pure cellulose was converted to a mixture of phenols, cyclopentanones, and hydroquinones as well as other components. This liquefaction oil and others were examined for their use as fuel asphalt substitutes and wood adhesives. The product composition tended to change with liquefaction time. One major product of cellulose liquefaction, 2,5-dimethyl-1,4-benzenediol, was formed during a reduction-oxidation procedure involving acetoin and biacetyl. The use of alkaline catalysts under liquefaction at 300 C was shown to shift the mechanism from one involving aqueous pyrolysis (predominant furan formation) to one incorporating aldol and related condensations. 33 references, 1 figure, 4 tables.
Thermal oxidation for crystalline silicon solar cells exceeding 19% efficiency applying industrially feasible process technology

Thermal oxides are commonly used for the surface passivation of high‐efficiency silicon solar cells from mono‐ and multicrystalline silicon and have led to the highest conversion efficiencies reported so far. In order to improve the cost‐effectiveness of the oxidation process, a wet oxidation in steam ambience is applied and experimentally compared to a standard dry oxidation. The processes yield identical physical properties of the oxide. The front contact is created using a screen‐printing process of a hotmelt silver paste in combination with light‐induced silver plating. The contact formation on the front requires a short high‐temperature firing process, therefore the thermal stability of the rear surface passivation is very important. The surface recombination velocity of the fired oxide is experimentally determined to be below S ≤ 38 cm/s after annealing with a thin layer of evaporated aluminium on top. Monocrystalline solar cells are produced and 19·3% efficiency is obtained as best value on 4 cm2 cell area. Simulations show the potential of the developed process to approach 20% efficiency. Copyright © 2008 John Wiley & Sons, Ltd.
An overview of catalytic conversion of vegetable oils/fats into middle distillates

Due to scarce conventional petroleum fuel, there is a need to search for alternative renewable fuel that can be adopted for use in place of fossil fuel oil. Even the ester-based biodiesel has many limitations, such as low energy content, oxidative stability etc. Renewable hydrocarbon-based diesel obtained by hydroprocessing of vegetable oils/fats (2nd generation biodiesel) is one of the alternatives that is getting attention from both academia and industry. The present paper reviews the emerging processes, catalysts and operating conditions for the catalytic conversion of vegetable oils/fats into hydrocarbon-based diesel via hydroprocessing. Hydroprocessing of vegetable oils is similar to petroleum hydroprocessing, but requires slight modification and optimization in the catalyst, as well as process parameters. The current status and future scope of the catalyst and process for hydroprocessing of vegetable oil are discussed.
DISTRIBUTION AND OCCURRENCE OF ATRAZINE, DEETHYLATRAZINE, AND AMETRYNE RESIDUES IN GROUNDWATER OF THE TROPICAL ISLAND BARBADOS

The triazine herbicides atrazine (AT) and ametryne (AMET) are used extensively in Barbados to control weeds in sugar cane fields. These pesticides were monitored in groundwater (the primary source of potable water on the island) for the dry seasons of March–June, 1991 and January–May, 1992 and the wet season, July–December, 1992. Residues of either AT or AMET were detected in all 277 groundwater samples collected from 23 wells in three major groundwater catchments underlying heavily cultivated sugar cane fields. The concentration of AT and the metabolite deethylatrazine (DEAT) were in the range 0.11–2.61 μg/l with the highest occurrence in the most heavily cultivated sugar cane area, the Hampton catchment. These measured levels of atrazine in the groundwater, represent a relatively small fraction that may have leached from the annual application, and was estimated to be 0.12, 0.17 and 0.19% of the total amount applied to the Belle, Hampton and Western catchments respectively. These levels, however, are in general higher than those reported for related studies and lower application rates of atrazine in sugar cane plantations should be considered to help preserve the quality of potable water on the island.
Sorption and Fractionation of Copper in Soil at a Sewage Irrigation Farm in Australia

Abstract Copper (Cu) is an important heavy metal to be considered in soil contamination, because high concentrations of copper in soil produce toxic effects and may accumulate in plant tissues. In Australia's oldest sewage irrigation farm, located in Werribee, Victoria, soil in the land filtration area is contaminated by Cu. However, Cu content in herbage tissues is in the normal range and has been trending downward since 1979. Therefore, studies on the sorption capacity and sequential extraction of Cu in soil at the Werribee Farm is of significance, not only for better understanding the mechanism of transport, chemical processes, and plant uptake of Cu, but also in providing information for the practical management of sewage farm soils. Methods of combining sorption isotherms with sequential extraction procedures were adopted, and the results showed that the soil in the land filtration area at Werribee Farm has a high sorption capacity for Cu, and distribution coefficients, Kf of Cu, were 629 L kg−1 in surface soils (0–20 cm) and 335 L kg−1 in subsurface soils (20–40 cm). The sequential extraction fractions demonstrate that exchangeable and carbonate fractions are very low, only comprising 3.49 to 5.49% of total copper. The other fractions are also discussed. This characteristic of Cu in soil is related to the low concentration of Cu in plant tissues.
Toward a Generalized Algorithm for the Automated Analysis of Complex Anisotropic NMR Spectra

An existing algorithm, founded on the works of Stephenson and Binsch, for the automatic analysis of isotropic or simple anisotropic NMR spectra has been improved to treat very complex NMR spectra of molecules dissolved in nematic solvents. The main options added to the original algorithm are a wider choice of smoothing functions; the use of the principal component regression method; and the possibility of selecting molecular coordinates, order parameters, and spectral parameters as variables of the problem. By means of these new options, it has been possible to analyze automatically NMR spectra (even depending on 27 spectral parameters) of 16 molecules in an anisotropic environment. Details of each case are discussed.
Simplifying the Analysis of Soil Particle Sizes. I. Test of the Sur and Kukal's Modified Hydrometer Method

Abstract This study tests the validity of the Sur and Kukal modified hydrometer method for particle size analysis on eight Ghanaian soils of varying texture. The method assumes that hydrometer readings at any time could be predicted from an exponential equation provided that two important parameters are known: the 4.5-min hydrometer reading (R 4.5) and the exponent (B). In a series of sedimentation experiments conducted on each soil in this study, 11 hydrometer readings were taken between 40 s and 8 h. Some of these data were used to determine the value of the parameters R 4.5 and the exponent B. The B values for the light textured soils were within the range of 4.2 × 10−3 to 9.7 × 10−3 and were comparatively lower than those for the heavy textured soils (1.0 × 10−2 to 1.5 × 10−2). In addition, the R 4.5 values were much lower for the light textured soils than for the heavy textured soils. Using these parameter values in the Sur and Kukal's equation enabled the prediction of the hydrometer readings at different times during the sedimentation process. The predicted 8-h hydrometer reading also was used to calculate the percent clay. A comparison between the observed and predicted hydrometer readings was satisfactory. The predicted percent clay also agreed very well with that observed for all soils (R 2 = 0.96). It is concluded that the Sur and Kukal method indeed simplifies the determination procedure and yields acceptable results for a wide range of Ghanaian soils.
Indium-Doped Zinc Oxide Thin Films as Effective Anodes of Organic Photovoltaic Devices

Indium-doped zinc oxide (IZO) thin films were prepared by low-cost ultrasonic spray pyrolysis (USP). Both a low resistivity ( cm) and an average direct transmittance ( nm) about 80% of the IZO films were achieved. The IZO films were investigated as anodes in bulk-heterojunction organic photovoltaic (OPV) devices based on poly(3-hexylthiophene) and [6,6]-phenyl C61-butyric acid methyl ester. The device fabricated on IZO film-coated glass substrate showed an open circuit voltage of 0.56 V, a short circuit current of 8.49 mA cm−2, a fill factor of 0.40, and a power conversion efficiency of 1.91%, demonstrating that the IZO films prepared by USP technique are promising low In content and transparent electrode candidates of low-cost OPV devices.
Dynamical Mapping of E. coli Thioredoxin via 13C NMR Relaxation Analysis

NMR relaxation analysis was used to characterize the internal dynamics of oxidized E. coli thioredoxin in both the picosecond-nanosecond and microsecond-millisecond frequency ranges for 413 H−C and H−N bond vectors. The 13C relaxation data was obtained utilizing protein samples possessing an alternating 13C−12C−13C. labeling pattern for most enriched sites. When combined with partial deuteration, this labeling pattern provides for isolated 1H−13C IS spin pairs exhibiting dynamically interpretable relaxation behavior. Side chains were found to exhibit a far broader range of dynamics than have been previously characterized for main chain resonances. The dynamics of structurally buried aromatic and leucine side chains are interpreted in terms of correlated main chain-side chain torsional oscillations. Structural regions exhibiting millisecond dynamics were found to correlate strongly with the presence of side chain-main chain or bifurcated main chain hydrogen bonds. Nuclei around the active site disulfide .
Anisotropic reorientational relaxation of biphenyl: Transient grating optical Kerr effect measurements

Subpicosecond transient grating optical Kerr effect measurements have been used to evaluate the reorientation of biphenyl molecules in neat biphenyl and n‐heptane solutions. Besides an ultrafast (100 fs time scale) component associated with librational damping/dephasing, two reorientational relaxation components are observed. The slow reorientation is due to rotation around the short axes of the molecule (tumbling motion), the fast reorientation is associated with internal rotation around the central C–C bond and/or rotation of the whole molecule around its long axis (spinning motion). Whereas the tumbling motion has been observed in earlier depolarized light scattering data, the time resolved Kerr data presented here are the first ones to reveal the dynamics of the fast reorientation component and the ultrafast librational dynamics. It is shown that the diffusive reorientational relaxation must be coupled to the ultrafast librational dynamics, and implications of this coupling are pointed out.