Miracle-dz/UniFAR-FTUs huggingface dataset:
Cell suspension culture of Arnebia euchroma (Royle) Johnston – A potential source of naphthoquinone pigments

The roots of Arnebia euchroma contain naphthoquinone red pigments, which have been used as colorant in food, cosmetics and as a dye for textile industries. Besides, these have medicinal and pharmaceutical properties too. Cell suspension culture serves as an alternative for secondary metabolite production. In this study, various growth factors such as inoculum build up process, phosphate source and in situ extraction methods were investigated on naphthoquinone pigment yield in A. euchroma cell suspension cultures. Effect of direct (solid to liquid) and in-direct (liquid to liquid) inoculum build up process was clearly evident, as direct inoculum registered 19.53% higher pigment yield than in-direct. Increased pigment yield was recorded in media having potassium phosphate sources (KH2PO4 and K2HPO4) rather than sodium (NaH2PO4) or ammonium (NH4)H2PO4. In situ extraction resulted in significantly higher yield of naphthoquinone derivatives (637.15 mg L-1) than control (369.38 mg L-1), along with higher volumetric and specific productivities. The density of liquid paraffin also influenced the in situ extraction. HPLC chromatograms showed acetylshikonin as the major naphthoquinone derivative in the quantified fraction. The results of present investigation revealed that optimized growth factors have significantly enhanced the yield (up to 72%) of naphthoquinone pigments.
Effects of Anode Material and Fuel on Anodic Reaction of Solid Oxide Fuel Cells

In this paper, anodic properties of solid oxide fuel cells are evaluated for several anode/electrolyte systems. Anodic over-voltage of metal/yttria-stabilized zirconia (YSZ) interface was related with metal-oxygen bonding strength and was the smallest for the Ni anode in the present study. The anodic polarization conductivity of Ni-YSZ cermet/YSZ electrolyte interface strongly depended on oxygen partial pressure P[sub 02], in fuel, but was independent of the kind of fuel (H[sub 2]-H[sub 2]O, CO-CO[sub 2] and CH[sub 4]-H[sub 2]O). The activation of oxygen ion appears to be the rate limiting step in the overall reaction. The overvoltages of Ni/ and Pt/samaria-doped ceria (SDC) were very small as compared with those of Ni/ and Pt/YSZ. The anodic properties were also influenced by the oxide material mixed with Ni as a cermet component.
Preparation and Properties of Resorcinol–Formaldehyde Organic and Carbon Gels

A brief overview on the preparation and properties of resorcinol–formaldehyde organic and carbon gels reveals very interesting features about their structural and performance characteristics. The resulting nanostructure was very sensitive to the various synthesis and processing conditions. This leads to a remarkable potential for designing and tailoring these materials to fit specific applications. Based on step‐by‐step comparisons of the published studies, approximate generalizations on the specific roles the synthesis and processing conditions play on the final properties are provided. Overall, resorcinol–formaldehyde organic gels undergo two main stages during synthesis. The first stage is associated with the preparation of the sol mixture, and the subsequent gelation and curing of the gel. The second stage is associated with the drying of the wet gel. The most important factors that affect the properties of the organic gel during the first stage are the catalyst concentration, the initial gel pH, and the concentration of the solids in the sol. The most important factors that affect the properties of the organic gel during the second stage are the drying procedure (e.g., super‐ or subcritical drying), and the difference between the surface tensions of the solvent before and after drying. The corresponding resorcinol–formaldehyde carbon gels are produced from the organic gels during a third stage, which is associated with carbonization or activation. Depending on the conditions, carbonization and activation both impact the structural and performance characteristics significantly.
Métodos para preparar hidrogeles químicos y físicos basados en almidón: Una revisión

Hydrogels from native starch, from its pure components (amylose and amylopectin) and from its derivatives are more attractive for some applications than synthetic hydrogels, mainly due to its biodegradability. In this work, some chemical and physical methods for hydrogels preparation are summarized. For the production of physical hydrogels, different strategies are presented based on hydrophobic interactions; charge interactions, hydrogenbonding and stereo-complexation. For the preparation of chemical hydrogels, the free radical grafting copolymerization of vinyl monomers induced by radiation or by chemical initiators is analyzed. Also, different ways for producing physical and chemical crosslinking are included. Furthermore, the production of hydrogelsnanocomposites is introduced as an alternative way to generate materials with improved properties.
Reevaluating the contribution of sulfuric acid and the origin of organic compounds in atmospheric nanoparticle growth

Aerosol particles formed in the atmosphere are important to the Earth's climate system due to their ability to affect cloud properties. At present, little is known about the atmospheric chemistry responsible for the growth of newly formed aerosol particles to climate‐relevant sizes. Here combining detailed aerosol measurements with a theoretical framework we found that depending on the gaseous precursors and size of the newly formed particles, the growth was dominated by either sulfuric acid accompanied by ammonium or organic compounds originating in either biogenic emissions or savannah fires. The contribution of sulfuric acid was larger during the early phases of the growth, but in clean conditions organic compounds dominated the growth from 1.5 nm up to climatically relevant sizes. Furthermore, our analysis indicates that in polluted environments the contribution of sulfuric acid to the growth may have been underestimated by up to a factor of 10.
Composition and clues to the origin of refractory metal nuggets extracted from chondritic meteorites

Refractory metal nuggets (RMNs) contain elements, such as Os, Ir, Mo, and Ru, which are predicted to condense from a cooling gas of solar composition simultaneously with CAI‐minerals. Berg et al. ( ) identified a large number of RMNs in acid‐resistant residues of the Murchison meteorite and suggested that they are pristine condensates. In extending the work of these authors, we have improved the chemical extraction process to enrich the concentration of RMNs in the residue sample and prepared three additional RMN‐rich residues from the chondritic meteorites Murchison, Allende, and Leoville. The results show that, while their origin is clearly solar, the compositions in detail of RMNs from all three meteorites do not match well with a simple condensation model based on equilibrium thermodynamics and ideal solid solution of all metals. Thus, we find that a primary formation by direct condensation, as suggested previously, is unlikely for most of the studied grains and that alternative scenarios should be considered in future work. The results also show that several, but not all, alloys from Allende and Leoville have undergone processes, such as metamorphic oxidation and sulfidization in the meteoritic environment, in which they lost, e.g., W and Mo. For Murchison and several Leoville and Allende RMNs, we propose a pristine nature.
Concentrations and Health Risk Assessments of Heavy Metals in Fish from the Fosu Lagoon

Concentrations of Cu, Pb, Cr, Cd, Mn, Ni, Fe and Zn were determined in the muscle samples of Sarotherodon melanotheron from the Fosu Lagoon in Cape Coast using atomic absorption spectrophotometer. The results showed that, metal concentration in the fish muscle was in the order Mn > Zn > Fe > Pb > Ni > Cd > Cu > Cr. Mean concentrations of Pb and Cd in the fish exceeded the maximum tolerable limit set by the European Union. Although the mean concentrations of some metals exceeded this limit, their estimated daily intakes were below their oral reference dose recommended by the international regulatory bodies. Health risk assessment of consumers from the intake of metal contaminated in the muscle of S. melanotheron from the lagoon was evaluated by using Health Risk Index (HRI) calculations. In this study, the total HRI through consumption of fish calculated by adding the individual HRIs was less than 1, indicating that there is no significant potential health risk associated with the consumption of fish from the Fosu Lagoon.
Inorganic-organic Hybrid Materials (ORMOCERs) for Multilayer Technology – Passivation and Dielectric Behavior

Inorganic-organic hybrid polymers (ORMOCER ® s) have been synthesized by sol-gel processing. The materials can be functionalized such that their physical and chemical properties can be reproducibly tailored towards the desired application, i.e., electronics, optics (passives/actives) or passivation technology. Besides, the materials which show negative resist behavior, can be patterned by UV exposure with good resolution. The materials are well-suited for thin and thick film technology using conventional coating technology, applied in multi-layer technology. We here particularly focus on materials for passivation against environmental influences, which additionally exhibit very good dielectric properties.
Solid‐state cultivation of Chaetomium cellulolyticum on alkali‐pretreated sawdust

Solid‐state fermentations (78% initial moisture content) of alkali‐pretreated Eastern Hard Maple sawdust were conducted in tray and tumble fermentors using chaetomium cellulolyticum. Crude protein content of the solids rose from 0.9 to 11% in the tray fermentor and 8% in the tumble fermentor in 20 days. These levels were almost equal to those achieved in corresponding slurry‐state fermentations (1–5% (w/v)) of the same substrate. Specific growth rates were two to four times lower in the solid‐state fermentors but this was offset by their greater solids‐handling capacity: the rate of protein production per unit volume of fermentation mixture was comparable to that of the 5% (w/v) slurry and two to three times higher than that of the 1% (w/v) slurry.
Use of PCA-RBF model for prediction of chlorophyll-a in Yuqiao Reservoir in the Haihe River Basin, China

Chlorophyll-a is a well-accepted index for phytoplankton abundance and population of primary producers in an aquatic environment. The relationships between chlorophyll-a and 18 chemical, physical and biological water quality variables in YuQiao Reservoir (YQR) in the Haihe River Basin in P.R. China were studied by using principal component analysis (PCA) coupled with a radial basis function network (RBF) model to predict chlorophyll-a levels. Principal component analysis was used to simplify the complexity of relations between water quality variables. Score values obtained by PC scores were used as independent variables in the RBF models. In the forecast, only five selected score values obtained by PC analysis were used for the prediction of chlorophyll-a levels. Correlative analysis between the modeled results and observed data indicates that the correlative coefficient is 0.61, and analysis of the forecast error rate shows that the average forecast error is 32.9%, proving the viability of the forecast model.
Orientation and Dynamics of NO2 in a N2O4 Host Matrix Prepared on a Plane Surface Investigated by ESR Line Shape Analysis

Thick films (approximately 100 μm) of NO2/N2O4 were prepared in a combined ultrahigh-vacuum ESR apparatus by adsorption of gaseous NO2 through a dosing system on a single-crystal surface (NiAl(110)). The adsorption temperature was in the range from 35 to 65 K. The line shapes of the ESR spectra are dependent on the adsorption conditions and show remarkable changes in heating processes. These observations can be explained in terms of geometrical rearrangements and molecular dynamics of the NO2 monomers. The line widths vary from 2 to 10 G depending on the concentration of ESR-active molecules through magnetic dipolar interactions. In all cases the observed line shape itself cannot be described by a simple distribution of randomly oriented molecules. The analysis of the spectra indicates a preferred molecular orientation with the NO2 C2 axis perpendicular to the surface plane of the substrate. The spectra are fitted by computer simulation using a line width that depends on the z component of the nuclear spi.
Polymorphism of crystalline poly(hydroxymethyl) compounds. III. The structures of crystalline and plastic tris(hydroxymethyl)aminomethane

Between 5 °K and its m.p. (446.0 °K), tris, H2NC(CH2OH)3, exhibits one phase transition, at 407.3 °K, to form the orientationally disordered (plastic) phase I. The ordered form, phase II, is orthorhombic, Pn21a, a=8.844(1) A, b=7.794(1) A, c=8.795 (1) A, Z=4, Dx=1.327 g/cm3, and Dm=1.320 g/cm3. The crystal structure can be described in terms of layers of molecules approximately normal to the c axis, with strong intralayer hydrogen bonding and weak interlayer hydrogen bonding. The crystal structure of phase II was studied using x‐ray diffraction at 144, 295, 297, 348, 382, and 395 °K. Full‐matrix least‐squares refinement of single‐crystal diffractometer data resulted in R values between 2–4% for all but the highest‐temperature data sets. Although the integrity of the structure is maintained throughout this temperature range, subtle effects are noted that indicate the increased thermal motion as phase I is approached. Phase I is body‐centered‐cubic, Im3m, with a=6.876(6) A at 423 °K, Z=2, and Dx=1.237 g/cm3.
Crystallochemical classifications of phyllosilicates based on the unified system of projection of chemical composition: I. The mica group

Abstract A unified system of vector representation of chemical composition is proposed for the phyllosilicates based on projection of the composition, as given by crystallochemical formula, onto a field with orthogonal axes chosen for octahedral divalent cations, R2+, and Si (X, Y, respectively), and oblique axes for octahedral trivalent cations, R3+, and vacancies, □, (V, Z, respectively). Point coordinates for each set of axes were used to define the direction and length of the unit vectors for phyllosilicates belonging to different groups. Parallel to these fundamental directions the composition isolines were drawn in the projection fields. Applied to micas, this system enables control of the chemical composition by the general crystallochemical formula covering all varieties of Li-free dioctahedral and trioctahedral micas: where z (number of vacancies) = (y-x+ m)/2; m (layer charge) =1; u+y+z = 3. There is a similar formula for vacancy-free lithian micas: where w = m — x+y;m=1; u+y+w = 3, and for Li-free brittle micas: where z = (y — x+m)/2; m = 2; u+y+z = 3. Projection fields were used to classify micas.
A Corona-Stabilised Plasma Closing Switch

Corona-stabilised plasma closing switches, filled with electronegative gases such as SF6 and air, have been used in pulsed-power applications as repetitive switching devices for the last 10 years. Their high repetition-rate capabilities coupled with their relatively simple design and construction have made them suitable alternatives to thyratrons and semi-conductor switches. As well as having repetitive switching capabilities, corona-stabilised plasma closing switches have the potential to work at elevated voltages through the incorporation of multiple electrode sets. This allows high-voltage operation with inherent voltage grading between the electrodes. A further feature of the switches is that they have relatively low jitter under triggered condition. This paper reports on some of the operational features of a new design of corona-stabilised, cascade switch that utilises air at atmospheric pressure as the insulating gas.
Suppression of surface charge accumulation on Al2O3-filled epoxy resin insulator under dc voltage by direct fluorination

Surface charge accumulation on insulators under high dc voltage is a major factor that may lead to the reduction of insulation levels in gas insulated devices. In this paper, disc insulators made of Al2O3-filled epoxy resin were surface fluorinated using a F2/N2 mixture (12.5% F2) at 50 °C and 0.1 MPa for different durations of 15 min, 30 min and 60 min. A dc voltage was applied to the insulator for 30 min and the charge density on its surface was measured by an electrostatic probe. The results revealed significant lower surface charge densities on the fluorinated insulators in comparison with the original one. Surface conductivity measurements indicated a higher surface conductivity by over three orders of magnitude after fluorination, which would allow the charges to transfer along the surface and thus may suppress their accumulation. Further, attenuated total reflection infrared analysis and surface morphology observations of the samples revealed that the introduction of fluoride groups altered the sur.
Bioelectrodes modified with chitosan for long-term energy supply from the body

A 3D nanofibrous network of compressed chitosan in the presence of genipin as the cross-linker, carbon nanotubes and laccase constitutes a new design to enhance the stability and the biocompatibility of biocathodes. The in vitro delivered current was around −0.3 mA mL−1 for 20 days under continuous discharge. A thin film made of chitosan cross-linked with genipin was synthesized and optimized for oxygen and glucose diffusion. This film was used as a biocompatible barrier on the surface of biocathodes implanted in rats. The biocathodes remained operational after 167 days in vivo. This biocathode design minimised the inflammatory response in the first two weeks after implantation. After several months, the growth of macrophages was observed. The electrical connection and the catalytic activity of the enzyme entrapped into the biocathode were demonstrated after almost 6 months of implantation by the ex vivo measurement of the OCP (0.45 V to 0.48 V) and the delivered current (−0.6 mA mL−1) under optimal conditions.
Study of the structural units in some chalcogenides of the As-Sb-S-Se-I system by X-ray and DSC analysis

The paper describes a study carried out with the aim of establishing the elements of structural network of the fivecomponent non-crystalline samples. X-ray powder diffraction at room temperature and temperatures up to 620 K and differential scanning calorimetry (DSC) studies of the glasses from the pseudo-binary system (As2Se3)100−x(SbSI)x have been realized. On the basis of the obtained results, it was possible to identify the appearance of different structural units in the crystallization processes above glass transition temperature Tg in the materials with various atomic percent of SbSI. The DSC experiments, carried out up to 700 K, showed that the temperature regions of crystallization translates to lower temperatures with increasing SbSI content. Structural unit of antimony-sulfoiodide exists in materials with x≥50 at. %. Thermal analysis showed the presence of two distinctive temperature domains of crystallization of the glasses with 70 and 80 at. % SbSI. Also, partial overlapping of glass transition and crystallization processes were found in the sample with x=80 at. % SbSI.
Binding pattern of ferrocyphen upon interaction with cetyltrimethyl ammonium bromide in the presence of urea

Cetyltrimethylammonium bromide (CTABr) have been titrated against Ferrocyphen (Dicyano-bis-(1, 10-phenanthroline) iron II complex) in aqueous solution as a function of urea concentration which gave a sigmoidal binding isotherm. A simple method was introduced for resolution and characterization of binding set on the basis of binding capacity concept to give hill coefficient > 1.0. Hill coefficient greater than one are the experimental hall mark of cooperativity in which initial binding events render subsequent binding events more favorable. The degree of cooperativity is sensitive to the concentration of urea. The results are interpreted in terms of dielectric constant and decrease in the hydrophobic interaction between the complex (ferrocyphen) and the surfactant monomers. Key word: Binding isotherm, surfactant, cooperativity, hydrophobic ferrocyphen, binding capacity.
The Persistence and Fate of Malathion Residues in Stored Beans (Phaseolus vulgaris) and Maize (Zea mays)

Two experimental models simulating the traditional storage conditions prevalent in Kenya, i.e. the open basket model and the modern wooden box model, were used to study the rate of dissipation and fate of malathion residues in maize grains and beans stored for periods of up to one year at ambient temperatures averaging 23°C. The grain samples were initially treated with 10.36 mg kg -1 of radiolabelled malathion dust prior to storage and portions analysed at regular intervals for malathion, malaoxon and the transformation products isomalathion, malathion α-monocarboxylic acid and malathion β-monocarboxylic acid using a combination of chromatographic, radioisotopic and mass-spectrometric techniques. The findings showed a gradual penetration of malathion into the grains in amounts which were slightly higher in maize than in beans irrespective of the method of storage. After 51 weeks of storage, 34-60% of the initial residues persisted in all the grains. The total residual levels were slightly higher in beans than in maize irrespective of the storage methods though the persistence was a little higher in the wooden box than in the open basket. The rates of dissipation of the pesticide from the grains decreased with storage time and followed a biphasic pattern. Applying first-order reaction kinetics, the following half-lives were obtained : maize grains stored in open basket : 194 days ; maize grains stored in closed wooden box : 261 days ; beans stored in open basket : 259 days ; beans stored in closed wooden box : 405 days. Beans stored in the wooden box had higher levels of bound residues than those sampled from the open basket. This trend was similar in maize grains although the concentrations were lower. The analysis of malathion metabolites confirmed the degradation trend of the residues.
Physical and chemical properties, plant growth, and radionuclide accumulation effects from mixing phosphogypsum with some soils

Abstract Large areas of salt‐affected soils exists in Syria. Besides, large quantities of phosphogypsum (PG) are stacked in areas close to the fertilizer factories (radioactivity 350 to 400 Bq kg‐1) that may pose a negative impact on the environment. Different rates of PG (0, 0.25, 2.5, 5, and 25%) were mixed with three soils characterized by different level of salinity (ECe 5.25, 9.44 and 17.66 dS m‐1) to monitor the effect of mixing PG on the physical and chemical properties of the soils, plant growth and the accumulation of radionuclides in soils and plants. The high PG application rates (2.5, 5, and 25%) were used to monitor the effects of adding the normal application rate of PG (5 T ha‐1) for 10, 20, and 100 consecutive years. Soil‐PG mixtures were put in 8.5 kg pots where trifolium (Trifolium pilulare) and barley (Hordium vulgare var. Arabi Abyad) were seeded. The results showed that mixing PG increased the saturated hydraulic conductivity, reduced Cl‐1 and increased SO2‐ 4 concentrations in the sa.