Miracle-dz/UniFAR-FTUs huggingface dataset:
Effect of hydrothermal carbonization reaction parameters on the properties of hydrochar and pellets

Hydrothermal carbonization (HTC) is a promising upgrading process to convert various low energy‐density lignocellulosic biomass materials to homogeneous, energy‐dense HTC biochar, known as hydrochar. A novel two‐chamber reactor was designed and built to investigate the effects of HTC reaction parameters on the resulting hydrochar produced from woody biomass. Reaction parameters investigated included temperature (200–230°C), feedstock particle size (0.60–2.38 mm), and reaction time (1–5 min). Mass yield and higher heating value (HHV) of the hydrochar products were determined as two important measures. Reaction temperature was found to have a much stronger influence on mass yield and HHV than particle size or reaction time. Hydrochar can be formed readily into robust, dense pellets, without requiring any additional binding agent. Pellet density ranged from 1260 to 1320 kg m−3, while volumetric energy density ranged from 27.3 to 29.5 GJ m−3. Several analyses were performed on hydrochar pellets, including ultimate analysis, proximate analysis, and water immersion tests. Results are presented and discussed to illustrate the chemical composition, energy density, and water resistance of hydrochar pellets. This study confirmed that the HTC process can transform lignocellulosic biomass into a solid fuel with favorable properties, and provides insightful guidance regarding optimum reaction parameters for producing hydrochar and pellets in a continuous, industrial process. © 2014 American Institute of Chemical Engineers Environ Prog, 33: 676–680, 2014
Local Monomer Activation Model for Phase Behavior and Calorimetric Properties of LCST Gel-Forming Polymers

We investigate the phase diagrams and calorimetric signatures of gel-forming polymers with a lower critical solution temperature (LCST). We construct a model that captures many of the observed properties of this type of polymer. The model assumes the existence of a sharp internal conversion, at a characteristic temperature T*, in which monomers are activated from effectively hydrophilic to associative-hydrophobic states. The location of the gel transition is determined by Flory's model of gelation, while phase separation of polymer and solvent is determined by assuming that the effective immiscibility χ parameter is generated solely from gel-forming contacts. The resulting phase diagrams exhibit an immiscibility loop and a gel−sol boundary. At low temperatures both the phase and the sol−gel boundaries are almost independent of concentration. The gel transition does not produce a signature in the calorimetric properties (heat capacities at constant concentration), but the internal transition produces a cle.
DESIGN AND MODELLING HILBERT TRANSFORM BASED PHASE DETECTOR FOR ALL DIGITAL PHASE LOCKED LOOP

The Phase Locked Loop (PLL) is an almost always used electronics circuit for communication systems like modulator, demodulator, frequency generator and frequency synthesizer etc. All-digital phase locked loop (ADPLL) is digital version of the PLL. In this paper, a novel Hilbert transform based phase detection system for all-digital phase locked loop (ADPLL) is presented. The digital discrete time components are used to realize the phase detector system reducing the complexity of the design. The Hilbert transform based phase detection system provides a definite advantage over conventional analog phase detectors with both sinusoidal and its Quadrature signal. The studied system is modelled and tested in the MATLAB/Simulink environment
New Multicomponent Bioerodible Electrospun Nanofibers for Dual-controlled Drug Release

The objective of this study was to evaluate the bioerodible polymer poly(maleic anhydride-alt-2-methoxyethyl vinyl ether) n-butyl hemiester, for multicomponent drug-loaded nanofibers produced by electrospinning. Diclofenac sodium (DS) and human serum albumin (HSA) were used as conventional drug and biopharmaceutical models. The influence of drug loading was correlated to beads presence, morphology and fibers diameter. When DS and HSA were loaded separately, a uniform distribution within fibers and beads was observed. However, when both components were loaded simultaneously, a heterogeneous distribution of DS was observed with a prominent amount in the cylindrical beads. The in vitro drug release evaluation from these nanomaterials displayed an independent delivery of the two components. These studies support the feasibility of multicomponent, bioerodible polymeric nanofibers preparation loaded with combination of traditional drugs and proteins.
Triblock Copolymers with Grafted Fluorine-Free, Amphiphilic, Non-Ionic Side Chains for Antifouling and Fouling-Release Applications

Fluorine-free, amphiphilic, nonionic surface active block copolymers (SABCs) were synthesized through chemical modification of a polystyrene-block-poly(ethylene-ran-butylene)-block-polyisoprene triblock copolymer precursor with selected amphiphilic nonionic Brij and other surfactants. Amphiphilicity was imparted by a hydrophobic aliphatic group combined with a hydrophilic poly(ethylene glycol) (PEG) group-containing moiety. The surfaces were characterized by dynamic water contact angle, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and near edge X-ray absorption fine structure (NEXAFS) analysis. In biofouling assays, settlement (attachment) of both spores of the green alga Ulva and cells of the diatom Navicula on SABCs modified with Brij nonionic side chains was significantly reduced relative to a PDMS standard, with a nonionic surfactant combining a PEG group and an aliphatic moiety demonstrating the best performance. Additionally, a fouling-release assay using sporelings (young .
Ferroelectric and antiferroelectric liquid crystalline phases in some pyridine carboxylic acid derivatives

The synthesis and mesomorphic properties of two series of compounds viz.(S)-(+)-4-(1-methylheptyloxy)phenyl 4′-(6″-alkoxypyridine-3-carbonyloxy)benzoates and (S)-(+)-l-methylheptyl4-[4′-(6″-alkoxypyridine-3-carbonyloxy)benzoyloxy]-benzoates are reported; the homologues of the former series exhibit smectic A and smectic C* phases while the derivatives of the latter series show rich polymesomorphism including the antiferroelectric phase. The mesophases have been characterised by using optical polarising microscopy and differential scanning calorimetric methods. Some physical properties such as the spontaneous polarisation, helical pitch, tilt angle and relative permittivity of two derivatives have also been investigated.
Application of a Compaction Simulator to the Design of a High-Dose Tablet Formulation. Part I

AbstractThe compaction properties of an investigational drug are studied by the use of a compaction simulator. The effects of punch velocity over the range of 30-640 mm−1 on the compaction properties of the pure drug and a variety of formulas incorporating a high dose of the active compound have been investigated. The data were analyzed by applying the Heckel equation. The pure drug was found to have a high yield pressure at a relatively low punch velocity of 31 mm−1. As the punch velocity was increased there was a decrease in crushing strength, primarily as a result of increasing yield pressure. These findings indicate that the pure drug predominantly consolidated by fragmentation and elastic deformation, with a slow plastically deforming component. The information obtained on the consolidation mechanism of the pure drug and, subsequently, on model formulas were instrumental in the design and selection of a robust formula and granulation process. The advantages of conducting dosage form design and charac.
Effect of Aluminium Stress on Germination and Mineral Nutrition of Kidney Bean Cultivars with Different Sensitivity to Aluminium

Aluminium is the most important element in the soil as a stable complex with oxygen and silicates. When pH is below 5, aluminium dissolves in soil water and is absorbed by plant roots. Aluminium toxicity is a major constraint to agricultural production in the world, because 50% of the world’s potential lands are acidic. Hence this study was conducted to investigate the toxic effects of aluminium on the germination and nutrient uptake in five cultivars of kidney beans (Derakhshan, Goli, Akhtar, Sayad and Naz) at three concentrations (30, 40, and 50mM) aluminium nitrate, Al(NO 3 ) 3 . Due to aluminium toxicity, reduced germination and growth of seedlings was recorded in all cultivars. Absorption of various nutrients, such as Fe, Ca, Mg, K, p, N decreased in roots and shoots of all cultivars. P and Mg Contents of shoots were less affected in all cultivars. Two cultivars including Derakhshan and Goli were better in terms of growth and accumulation of minerals than the other three. In General, germination and nutrient accumulation was inhibited in kidney bean due to the presence of aluminium.
The Biopersistence of Fibres Following Inhalation and Intratracheal Instillation Exposure

Summary Both inhalation and IT exposure provide estimates of the biopersistence of soluble fibres of similar magnitude. Inhalation systematically shows the faster clearance of longer fibres (L>20μm). For the one less soluble fibre evaluated in this study (RCF 1a), a large difference was observed between inhalation and IT exposure although as mentioned above this may be due to possible agglomeration in the bronchi following IT exposure. The results from both inhalation and IT studies were reproducible. Both methods require extensive controls to be valid. Inhalation exposure requires the aerosol to be rat respirable while IT requires confirmation of no agglomeration of fibres in the fibre suspensions used for injection and in the bronchi of the lungs following injection.
Preparation and Characterization of Polyacrylonitrile-Polyaniline Blend Nanofibers

Composite nanofibers of polyaniline doped with dodecylbenzene sulfonic acid (PANI-DBSA) and polyacrylonitrile (PAN) were prepared via an electrospinning process. The surface morphology of PANI-DBSA/PAN nanoﬁbers was characterized using scanning electron microscopy (SEM). Differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were used to investigate the hydrogen bonding and miscibility behavior of the blend. It was found that the average fiber diameter of composites nanofiber was increased with the increase of PANI-DBSA content. The formation of the hydrogen bonding between PAN and PANI-DBSA was identified by the FTIR spectra
The Influence of Selected Parameters on the Size and Shape of Alginate Beads Prepared by Ionotropic Gelation

Many bead biopharmaceutical characteristics are dependent on the bead shape. Furthermore, the shape is one of crucial parameters for incorporation of beads in more complex drug delivery system. Therefore, the aim of this study was to evaluate the influence of various processing parameters such as hardening time, temperature and concentration of calcium chloride solution and drying conditions on size, shape and morphology of alginate beads prepared by ionotropic gelation method. Theophylline was selected as a model drug. It was found that all studied parameters markedly affected bead form, resembling in most cases to ellipsoid spheres. Their sphericity was estimated three-dimensionally by measuring diameters of frontal and lateral side which were perpendicular to each other. Smaller and more spherical beads were obtained at longer hardening time and higher temperature of calcium chloride solution. The freeze-dried beads were the largest and the most spherical. It was demonstrated that optimization of bead shape as well as size and morphology could be achieved by altering processing parameters.
Highly Conductive and Transparent PEDOT:PSS Films with a Fluorosurfactant for Stretchable and Flexible Transparent Electrodes

Highly conductive and transparent poly‐(3,4‐ethylenedioxythiophene):poly(styrenesulfonic acid) (PEDOT:PSS) films, incorporating a fluorosurfactant as an additive, have been prepared for stretchable and transparent electrodes. The fluorosurfactant‐treated PEDOT:PSS films show a 35% improvement in sheet resistance (Rs) compared to untreated films. In addition, the fluorosurfactant renders PEDOT:PSS solutions amenable for deposition on hydrophobic surfaces, including pre‐deposited, annealed films of PEDOT:PSS (enabling the deposition of thick, highly conductive, multilayer films) and stretchable poly(dimethylsiloxane) (PDMS) substrates (enabling stretchable electronics). Four‐layer PEDOT:PSS films have an Rs of 46 Ω per square with 82% transmittance (at 550 nm). These films, deposited on a pre‐strained PDMS substrate and buckled, are shown to be reversibly stretchable, with no change to Rs, during the course of over 5000 cycles of 0 to 10% strain. Using the multilayer PEDOT:PSS films as anodes, indium tin oxide (ITO)‐free organic photovoltaics are prepared and shown to have power conversion efficiencies comparable to that of devices with ITO as the anode. These results show that these highly conductive PEDOT:PSS films can not only be used as transparent electrodes in novel devices (where ITO cannot be used), such as stretchable OPVs, but also have the potential to replace ITO in conventional devices.
Preparation of Supported Catalysts by Deposition–Precipitation

The sections in this article are Introduction Supported Catalysts Production of Supported Catalysts Selective Removal of One or More Component Application on Separately Produced Supports Impregnation and Drying of Supports Precipitation onto a Suspended Support The Theory of Nucleation [13, 14] Deposition–Precipitation on Suspended Supports Survey of Deposition–Precipitation Procedures Deposition–Precipitation by Changing the pH Limited Subsequent Reaction of the Precipitated Precursor Subsequent Reactions of the Initially Precipitated Precursor Reduction of Precursors Prior to Deposition–Precipitation Changing the Valency of Precursor Ions Removal of a Complexing Agent Electrochemical Deposition–Precipitation Deposition–Precipitation of Gold Deposition–Precipitation within Pre-Shaped Support Bodies Production of Catalyst Supports and Synthetic Clay Minerals Concluding Remarks Acknowledgments Keywords: supported catalyst; nucleation; impregnation; deposition-precipitation; precursor ions
Iodinated Indole Alkaloids From Plakortis simplex − New Plakohypaphorines and an Evaluation of Their Antihistamine Activity

Three new iodinated tryptophan derivatives, plakohypaphorines D−F (4−6), have been isolated from the Caribbean sponge Plakortis simplex. Their structures have been determined by applying spectroscopic methods and microwave-assisted selective dehalogenation. Compound 5 is the first naturally occurring triiodinated indole, while compound 6 is a unique metabolite because it possesses both chlorine and iodine atoms on the indole nucleus. We have evaluated the antihistamine activity of the whole series of plakohypaphorines A−F, but only the diiodinated analogues proved to be active: they display a specific antagonism of the noncompetitive type. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Aerosol iron solubility in a semi-arid region: temporal trend and impact of anthropogenic sources

Asystematic 1-yr chemical data for the fine mode (PM2.5) air-borne particulate matter, collected from a high-altitude site (Mt. Abu, 22.7◦N, 74.6◦E, 1680 m asl) in a semi-arid region of western India, reveal characteristic temporal variability in the abundance of mineral dust and fractional solubility of aerosol Fe (referred as water-soluble Fe). A notable feature of the data is seen from an inverse relationship between aerosol Fe (range: 50–915 ng m−3) and fractional Fe solubility (range: 0.06–16.1%). A significant increase in the solubility of iron, during wintertime, is also marked by a uniform decrease in the mass fraction of mineral dust. These observations suggest that the advective transport of pollutants and Fe derived from combustion sources is one of the possible causes for the enhanced solubility of iron over a semi-arid region in western India. The relative dominance of anthropogenic sources, during wintertime, is also supported by a two to threefold increase in NH4+ and SO42− as well as enrichment of heavy metals in PM2.5 (ascertained from Pb/Al and Cd/Al ratios).
Stoichiometry and Flameholder Effects on a One-Dimensional Flame

Abstract The steady one-dimensional isobaric combustion of a gaseous premixture of fuel and oxidant under a direct one-step irreversible Arrhenius-type exothermic chemical reaction is studied analytically for constant, but general, Lewis-Semenov number. Limit-process expansions are used to obtain solutions in the physically interesting limit of activation temperature large relative to the hot-boundary temperature. The eigenvalue or critical flow speed for an adiabatic system is established as a function of departure from stoichiometry. It is emphasized that, for relatively small departures from stoichiometry, the bimolecular system behaves as a monopropellant decomposition, to lowest order of approximation, because the richer reactant is effectively undepleted. The porous-disk-type flameholder for a flat-flame burner is modeled as a (nonadiabatic) heat source (supercritical flow speed) or heat sink (subcritical flow speed). The flame stand-off distance and the amount of departure of the hot-boundary tempe.
Methodology for the assessment of human health risks associated with the consumption of chemical contaminated freshwater fish in South Africa

Studies have shown that the aquatic environment can be polluted by contaminates that are accumulated by freshwater fish and this may pose a health risk to the consumers of the contaminated fish. Developed counties like the United States of America have developed strategies and associated guidance documentation to conduct chemical contaminant surveys using fish and to use these data to reduce the heath risk to the consumers of the fish. In this paper a generic methodology is presented that will give guidance in the undertaking of fish contaminant surveys to provide information regarding the possible health risk if the fish are consumed by recreational and subsistence fishermen in South Africa. The fundamentals of the methodology are based on catchment information, socio-demographic information of consumers of fish in the catchment, bioaccumulation potential and health risks of analytes, sound sampling design, risk assessment procedures and performing monitoring at different scales and depths. These aspects are presented as 10 major steps in the methodology of which the basic requirements are discussed to focus the surveys and optimise the application of resources. Although the methodology focuses on assessing the possible health risk to the consumers of fish many of the aspects would apply to any investigation aimed at assessing the chemical contaminant levels in fish. Furthermore as these surveys identify areas in the aquatic system where fish have unacceptably high chemical contaminant levels, this information can be used in catchment management programmes to put remedial actions in place that would ensure that the fish populations of the system are fit for present and future human consumption. Water SA Vol.29(1) 2003: 69-90
Evaluation of freeze-concentrated sugar-cane juice

Sugar-cane (Saccharum officinarum) juice with initial total soluble solids (TSS) of 15 °Brix was extracted from blanched sugar-cane stalks and was used for the production of a double strength (30 °Brix) sugar-cane juice using a freezeconcentration process. The freeze-concentrated juice was lower in yeast and mould count, pH and colour values, but higher in non-enzymic browning (NEB) index, chlorophyll content, total aerobic count and relative viscosity as compared to the fresh juice. A sensory evaluation performed on the samples indicated that fresh sugar-cane juice had higher hedonic scores in sweetness, flavour, aftertaste and overall acceptability as compared to that of freeze-concentrated juice (30 °Brix). The sensory scores of concentrated juice, however, improved upon reconstitution with mineral water. Reconstituted juice with TSS of 15 °Brix and 20 °Brix had the highest hedonic scores for the flavour, sweetness, aftertaste and overall acceptability attributes as compared to other reconstituted juice. During storage, the TSS and pH values of freeze-concentrated juice stored at 10 °C and 25 °C decreased considerably with storage times, and the decrease was more pronounced in the juice stored at 25 °C. The TSS and pH values, however, were unchanged at storage temperatures of –18 °C and 4 °C. The colour values and NEB index of all juice were not affected by the storage temperatures used.
Adsorption of an Organic Corrosion Inhibitor on Iron and Gold Studied with a Rotating EQCM

Adsorption of a carboxylic acid-based corrosion inhibitor was studied on gold and iron electrodes using a rotating electrochemical quartz crystal microbalance (rEQCM) electrode developed in our laboratory. The thin film electrodes were deposited on 10 MHz AT-cut quartz crystals. Concurrently, the adsorption was characterized with impedance. The inhihitor concentration was stepwise increased during the potentiostatic measurements. Addition of inhibitor resulted in an immediate increase of the resonant frequency up to a monolayer coverage. The apparent mass loss corresponding to the observed frequency increase can be explained by the replacement of water in the interfacial volume occupied by the adsorbing inhibitor molecules, Langmuir-Freundlich. multisite Langmuir, and Flory-Huggins isotherms were applied to the EQCM data. The experimental results correspond best to a Langmuir-Freundlich-type adsorption behavior of the inhibitor. Calculated standard free energies of adsorption show a slightly stronger interaction between inhibitor and iron than inhibitor and gold. The present study demonstrates that the EQCM is a unique tool for the study of substitution phenomena related to adsorption of corrosion inhibitors at solid electrodes not accessible by other methods.
Physiological changes and defense mechanisms induced by cadmium stress in maize

Heavy metals such as cadmium (Cd) enter the ecosystem chiefly as the result of human activities. Nowadays the heavy-metal pollution of the soil is causing ever greater problems, exacerbated by the fact that the heavy metals accumulated in plants may, either directly or indirectly, find their way into animals and human beings. Maize is one of the world's most important crops, ranking third after wheat and rice, so the changes induced by one of the most toxic heavy metals, Cd, in maize plants is a cause of some concern. This review discusses not only the toxic symptoms caused by Cd stress, but also the tolerance mechanisms activated in the plants. Cadmium induces a number of physiological changes, such as growth inhibition, changes in the water and ion metabolism, the inhibition of photosynthesis, changes in enzyme activities, and the formation of free radicals. The synthesis and compartmentalization of phytochelatins is induced shortly after the initiation of Cd stress, while other defense mechanisms also play an important role.