Miracle-dz/UniFAR-FTUs huggingface dataset:
Synthesis and characterization of Fe-Al-Mn nanocomposite sorbent for phosphate sorption-desorption study

In this work, we evaluated the potential application of a ternary nanosorbent for predicting phosphate desorption kinetics from soil. Accordingly, ternary mixed oxide nanosorbents with Fe:Al:Mn mole ratios of 3:3:1; 6:3:1 and 2:4:1 were prepared using simultaneous oxidation and coprecipitation methods. The adsorbents were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) method, scanning electron microscope (SEM) coupled with EDX (energy dispersive X-ray) and Furrier transform infrared spectroscopy (FT-IR). The results indicated that the as-synthesized ternary oxides were either amorphous or crystalline depending on the composition from which the composite was formed, with specific surface area ranging from 41.2 to 243 m 2 g -1 . Among the three proportions considered, the one with Fe:Al:Mn in 3:3:1 mole ratio exhibited the highest surface area and was selected for P sorption-desorption studies. Phosphate removal gradually decreased with the increasing of pH from 4 to 10.5. Adsorption isotherms on the adsorbent at pH 6.5 followed the order: Freundlich > Temkin > Dubinin-Radushkevich > Langmuir. At 35 °C, the maximum adsorption capacity for the adsorbent was found to be 49.95 mg g -1 . The effect of coexisting anions on phosphate sorption followed the order: SiO 3 2- > CO 3 2– > SO 4 2– > NO 3 - and this is closely correlated with charge-to-radius ratios of the anions. The kinetic data were described better by the pseudo-second-order adsorption model. The as-obtained nanocomposite sorbent with good specific affinity towards phosphate is a promising adsorbent for soil P desorption studies. KEY WORDS : Nanostructure, Phosphate, Desorption kinetics, Ternary oxide, Adsorption isotherm Bull. Chem. Soc. Ethiop. 2018 , 32(3), 421-436. DOI: https://dx.doi. org/10.4314/bcse.v32i3. 2
PROTECTIVE AND THERAPEUTIC EFFECTS OF OLIVE OIL AND FICUS CARICA AS NATURAL ANTIOXIDANTS ON SOME BIOCHEMICAL PARAMETERS IN LIVER OF γ-IRRADIATED MALE ALBINO RATS

The present study was designed to determine the possible protective and therapeutic effects of olive oil, Ficus carica andboth against radiation induced oxidative stress and biochemical changes in liver of albino rats. A patch of 114 male Wisteralbino rats averaged weights 120±5 g at the beginning of the experiment were divided into 8 main groups and 19 subgroups according to the treatment and requirements of the experiment. Irradiation was performed by whole body exposure of rats to an acute single dose gamma radiation of 6 Gy. Irradiated rats received, via gavage, extra virgin olive oil (7.6 ml/kg b.wt), extract of Ficus carica fruit (1 g/kg b.wt) and the combined supplementation of both Ficus carica (1 g/kg b.wt) and extra virgin olive oil (7.6 ml/kg b.wt) before and/or after radiation exposure. Six rats were sacrificed on the 1st and 15th day post irradiation exposure at the control, treated and pretreated irradiated subgroups. In addition, six rats were sacrificed from the post-treated irradiated subgroups on the 15th day post irradiation exposure.In the present study, γ- irradiation induced dramatic results of all parameters and sever antioxidant and detoxification enzyme depletion. Exposure to γ- radiation resulted in a significant elevation of some hepatic parameters (TBARS, AOPP, SOD, ASAT, ALAT, and ALP) and a significant decrease in some other parameters (CAT, GSH and NO). Moreover, the present study showed a significant decrease in total protein, and albumin on the 1st and 15th day post-irradiation as compared to the control. The administration of the olive oil or Ficus carica or both had a beneficial result against the deleterious effects of γ-irradiation. In addition, all treatments showed a significant increase in TBARS and AOPP levels, enhance SOD and CAT activities, and improve GSH and NO concentrations in the liver homogenate. Furthermore, significant amelioration in the serum liver function enzymes activities (ASAT, ALAT and ALP), total protein, and albumin were observed in comparison to irradiated rats. A better ameliorative effect was noticed with the combined extra virgin olive oil and Ficus carica treatments that revealed the synergistic effect between them. In conclusion, according to the results obtained the administration of the olive oil or Ficus carica or both provides considerable radioprotective and radiotherapeutic effects against whole body γ- radiation in male Wister albino rats by preventing oxidative stress through ROS scavenger.
Transformation and ageing of biomass burning carbonaceous aerosol over tropical South America from aircraft in situ measurements during SAMBBA

Abstract. We present a range of airborne in situ observations of biomass burning carbonaceous aerosol over tropical South America, including a case study of a large tropical forest wildfire and a series of regional survey flights across the Brazilian Amazon and Cerrado. The study forms part of the South American Biomass Burning Analysis (SAMBBA) project, which was conducted during September and October 2012. We find limited evidence for net increases in aerosol mass through atmospheric ageing combined with substantial changes in the chemical properties of organic aerosol (OA). Oxidation of the OA increases significantly and rapidly on the scale of 2.5–3 h based on our case study analysis and is consistent with secondary organic aerosol production. The observations of limited net enhancement in OA coupled with such changes in chemical composition imply that evaporation of OA is also occurring to balance these changes. We observe significant coatings on black carbon particles at source, but with limited changes with ageing in both particle core size and coating thickness. We quantify variability in the ratio of OA to carbon monoxide across our study as a key parameter representing both initial fire conditions and an indicator of net aerosol production with atmospheric ageing. We observe ratios of 0.075–0.13 µgsm-3ppbv-1 in the west of our study region over the Amazon tropical forest in air masses less influenced by precipitation and a value of 0.095 µgsm-3ppbv-1 over the Cerrado environment in the east (where sm−3 refers to standard metre cubed). Such values are consistent with emission factors used by numerical models to represent biomass burning OA emissions. Black carbon particle core sizes typically range from mean mass diameters of 250 to 290 nm, while coating thicknesses range from 40 to 110 nm in air masses less influenced by precipitation. The primary driver of the variability we observe appears to be related to changes at the initial fire source. A key lesson from our study is that simply aggregating our observations as a function of atmospheric ageing would have been misleading due to the complex nature of the regional aerosol and its drivers, due to the many conflating and competing factors that are present. Our study explores and quantifies key uncertainties in the evolution of biomass burning aerosol at both near-field and regional scales. Our results suggest that the initial conditions of the fire are the primary driver of carbonaceous aerosol physical and chemical properties over tropical South America, aside from significant oxidation of OA during atmospheric ageing. Such findings imply that uncertainties in the magnitude of the aerosol burden and its impact on weather, climate, health and natural ecosystems most likely lie in quantifying emission sources, alongside atmospheric dispersion, transport and removal rather than chemical enhancements in mass.
Se doped ZnO nanoparticles with improved catalytic activity in degradation of Cholesterol

Pristine and Se doped ZnO nanoparticles (NPs) were successfully synthesized by thermo-mechanical method and their structural, morphological and optical properties are characterized. Here in, a series of experiments were carried out where cholesterol is treated with same concentration of Pristine as well as Se doped ZnO NPs. Several Cholesterol oxidation products (COP’s) such as 25-hydroxycholesterol and 26-hydroxycholesterol, 7α-hydroxycholesterol, 7β-hydroxycholesterol, 7-ketocholesterol are formed as observed by HPLC analysis. The batch of 5 wt % Se doped ZnO NPs exhibited highest cholesterol degradation efficiency followed by pristine ZnO NPs and 2 wt % Se doped ZnO NPs. The peak area corresponding to 7-ketocholesterol and 25-hydroxycholesterol is found to be 200980 AU and 200986 AU respectively. The mechanism of cholesterol degradation was correlated with incorporation of oxygen vacancies due to Se doping, which were likely intermediate levels for transiting photoexcited charge carriers for generation of hydroxyl radicals. Further, hydroxyl radicals generated during interaction of ZnO nanoparticles with aqueous media have been determined using terephthallic acid assay and 2′, 7′-di-chlorofluorescein (DCF) assay.
High performance liquid chromatography-diode array detection (HPLC-DAD) profiling, antioxidant and anti-proliferative activities of ethanol leaf extract of Berlinia grandiflora (Vahl) Hutch. Dalziel

Berlinia grandiflora is used for managing numerous ailments including tumor in South-west, Nigeria. The phytochemical contents, antioxidant and antiproliferative activities of B. grandiflora leaf were determined in this study. The absolute ethanol extract was evaluated by high performance liquid chromatography-diode array detection (HPLC-DAD). The antioxidant activity was carried out by standard analytical methods. The antiproliferative activity was done using growth inhibition activity of Sorghum bicolor seed radicle with methotrexate as the reference drug. The presence of some phytochemicals known to have antioxidant properties and exert anticancer effects is revealed in this study. The HPLC analysis revealed the presence of betulinc acid, ferulic acid, rutin and caffeic acid. However, ferulic acid, rutin, and caffeic acid were identified for the first time in B. grandiflora. Free radical scavenging activity, reducing power capacity and nitric oxide inhibitory activity were exhibited by the extract, with IC50 values of 88.3, 7.4 and 99 µg/mL, respectively. While ascorbic acid, the reference compound, used in this study has IC50 values of 0.7, 3.4 and 7.4 µg/mL, respectively. The total phenol content expressed in gallic acid equivalent (GAE) was 75 mg/g. A dose-dependent antiproliferative activity was observed with IC50 values of 0.50, 0.59 and 0.29 µg/mL after 48, 72 and 96 h of treatment, respectively. This result justifies the folklore use of the plant for managing cancer in Nigeria and the plant’s potential as a new phyto-chemo-therapy. Key words: Antiproliferative, antioxidant, phytochemicals, cancer, Berlinia grandiflora, betulinic acid.
Photocatalytic degradation of alizarin red dye in aqueous medium using carbon nanotubes/Cu–Ti oxide composites

ABSTRACT Multiwalled carbon nanotubes/copper and titanium oxides (MWNTs/Cu–Ti) and Cu–Ti composites were synthesized by wet chemical precipitation method and were used as photocatalysts for photodegradation of alizarin red dye in aqueous media. The morphological study presented that MWNTs are well covered by Cu–Ti. The formation of Cu–Ti was confirmed by energy dispersive X-rays (EDX) and X-rays diffraction (XRD). The MWNTs/Cu–Ti degraded about 92.51% within 180 min. The effect of other parameters like pH, catalyst dosage, and concentration of dye on the photocatalytic degradation was also studied. The activity of recovered and re-recovered catalysts was also studied.
Structural and Physicochemical Characteristics of Granular Malic Acid-Treated Sweet Potato Starch Containing Heat-Stable Resistant Starch

This study investigated the structural and physicochemical characteristics of malic acid-treated sweet potato starch. Sweet potato starch mixed with various concentrations of malic acid solution underwent either thermal or nonthermal treatment. Observation of samples under a light microscope ensured the maintenance of granular shape and the Maltese cross. FT-IR spectra displayed a distinct carbonyl peak at 1722 cm−1, and analysis of the degree of substitution (DS) indicated an increase in the extent of ester bonds with increasing concentrations of malic acid. The DS of 2.0M-130 (0.214) was the highest and that of 0.5M-130 was the lowest (0.088) among the reacted starches. In vitro digestion test revealed an increased amount of resistant starch when a high concentration of malic acid was used. In addition, thermally treated samples maintained a higher content of resistant starch (RS) after 30 min of cooking at 100°C. After cooking, 2.0M-130 had an RS fraction of 53.4% which was reduced to 49.9% after cooking, revealing greater heat stability compared with nonthermally treated samples. The structure of malic acid-treated starch was investigated using a differential scanning calorimeter (DSC), an X-ray diffractometer, a rapid visco analyzer (RVA), and analysis of apparent amylose content. The results showed that thermal and malic acid treatment of starch caused not only partial hydrolysis but also rearrangement of the crystalline area and helix structure of starch by esterification. Analysis of malic acid-treated starch, using a rapid visco analyzer showed no pasting properties, due to lack of its swelling caused by the malic acid cross link.
Contribution of the density-functional-based tight-binding scheme to the description of water clusters: methods, applications and extension to bulk systems

ABSTRACT This review is dedicated to the application of the self-consistent-charge density-functional-based tight-binding (SCC-DFTB) approach to describe the structures, energetics, thermodynamic and spectral properties of water clusters, in the context of both fundamental and applied studies. We first present modifications implemented in the parametrisation of the potential that is mandatory to describe molecular aggregates as well as methods for global optimisation and determination of macroscopic properties. Then a number of applications of atmospherical and astrophysical interest, involving collaborations between theoreticians and experimentalists, are discussed to exemplify past and present contributions of SCC-DFTB to those two domains. Most applications presented in this review take advantage of the computational efficiency of SCC-DFTB to conduct extensive molecular dynamics simulations to obtain spectral and thermodynamic properties of water clusters. We also show some new results related to ongoing studies on both water clusters with impurities and liquid water.
Wood Pulp Fiber Wrapped by Fish-Scale Graphene as Flexible and Free-Standing Supercapacitor Electrode

Poplar wood pulp was adopted as both frame and precursor for the synthesis of pulp fiber (PF)/reduced graphene oxide composite via a simple and low-cost method. In this method, the PF based on graphene (PFG) composite film electrode was prepared by a simple vacuum filtration process with various ratios (PF: reduced graphene oxide (RGO) = 5:1, PF:RGO = 5:2, PF:RGO = 5:3, PF:RGO = 5:4, PF:RGO = 5:5). In terms of special structures, the PFG can be used as electrodes without metal-collector, adhesives, and additives. The optimal ratio (PF:RGO = 5:4) film electrode displayed a high areal-specific capacitance of 683 mF/cm2 at 1 mA/cm2 with a mass of 5.3 mg/cm2 (specific capacitance of 129 F/g) and good cycling stability (87.5% capacitance retention after 10,000 cycles at 5 mA/cm2) as well as excellent rate capability and high flexibility (suitable for any angle, even 180°). Moreover, the device could possess a maximum energy density of 47.71 μWh/cm2 and a maximum power density of 1251 μW/cm2. These results suggest that the composite PGF film is a promising electrode material.
Synthesis and Characterization of Iron Oxide Nanoparticles by Thermal Decomposition Method of Iron (III) Chelates

Magnetic iron oxide nanoparticles have numerous applications in the biomedical field. This paper reports the preparation and properties of iron oxide nanoparticles synthesised by thermal decomposition method from iron chelates. The iron oxide nanoparticles were characterized by FTIR, powder XRD, VSM, SEM and TEM techniques. FTIR and powder XRD studies show that iron oxide was formed as α - Fe2O3 in its pure form. VSM study shows that the particles have got ferromagnetic property. XRD, SEM and TEM images show that the particles formed are in nanometre crystallite size.
The LES and LEM Study of End-Gas Auto-Ignition Mechanism in a Downsized Spark Ignition Engine: Effect of Turbulence

ABSTRACT The effect of turbulence on the end-gas auto-ignition process of different primary reference fuels (PRFs) under engine-relevant conditions is numerically investigated through 3-D LES (large eddy simulation) and 1-D LEM (linear eddy model) simulations. Spontaneous ignition in the end-gas and pressure oscillations under the knock condition of a downsized spark ignition engine are qualitatively captured through the LES simulation. In order to take a further insight into the effect of full-scale turbulence-chemistry interaction on the auto-ignition process of the end-gas, 1-D LEM simulations are performed in a 1-D domain composed of a homogeneous core region and a linearly thermal distributed boundary layer. The effects of turbulent fluctuating velocity, fuel composition, turbulence length scale and initial temperature on the ignition process are investigated in the present study. It is found that the turbulence has a non-monotonic influence in the auto-ignition (AI) formations and expansion process of the PRF/air mixtures. Increased turbulence intensity delays the formation of the initial AI and shrinks the kernel size at the onset of AI due to the enhanced heat and radicals dissipation. However, after the first AI kernel forms, the intensified turbulence accelerates the overall combustion as a result of expanded preheating zone and more homogeneous unburned mixtures caused by turbulent stirring. In addition, the dissipation and homogenization effects of turbulence on the high-octane fuel are more prominent than on the low-octane fuel. The analysis of cases with different turbulent integral length scales reveals that the dissipation effect of the turbulence with the similar length scale of the nascent AI kernel is more prominent while the small-scale turbulence is more apt to shift the combustion mode after the first auto-ignition flame forms. At a high initial temperature of 900 K falling in the NTC regime, the first AI kernel of PRF10 appears in the boundary layer with a lower temperature instead of the core region. As the turbulence intensifies, the effect of NTC on the end-gas auto-ignition vanishes.
Hysteresis in the Vaporization-Controlled Inertial Regime of Nonpremixed Counterflow Spray Combustion

ABSTRACT This numerical study uses a Lagrangian–Eulerian formulation employing the point-source approximation to investigate nonpremixed axisymmetric spray diffusion flames stabilized between a stream of hot air and a stream of nitrogen carrying a monodisperse spray of fuel droplets injected at a distance zl from the stagnation plane. The computations consider moderately large values of the relevant thermal Peclet number, such that the thickness of the mixing layer separating both streams is much smaller than zl. A one-step irreversible reaction is assumed between the fuel vapor and the oxygen of the air. Most of the computations consider the thermochemical, vaporization, and transport properties of dodecane, with additional results for the properties of methanol used to assess effects of higher fuel volatility. The analysis considers moderately small values of the liquid mass loading ratio at the injection plane, consistent with the stoichiometric value of the fuel-to-air mass ratio of the global oxidation reaction of typical hydrocarbon and alcohol fuels. Attention is mainly focused on inertial droplets with associated Stokes numbers St of order unity or larger, for which the droplets penetrate far into the oxidizer stream, vaporizing over distances of order zl and leading to combustion occurring outside the mixing layer. In this inertial regime, besides solutions involving a diffusion flame separating the fuel and oxygen with a well-defined peak temperature of the order of the adiabatic flame temperature, the analysis reveals, for the first time, the existence of flameless solutions with distributed combustion and small temperature increments from the air-side value. The two solutions are found to exist for the same sets of boundary conditions. Integrations for increasing values of St identify a value of the Stokes number St2 above which the vaporization rate is too small to support a diffusion-flame solution, while integrations for decreasing St lead to the identification of another value of the Stokes number St1 < St2 below which a distributed reaction cannot occur. In the intermediate hysteretic range St1 ≤ St ≤ St2 where two different steady solutions may exist, the type of solution encountered depends on the initial conditions imposed. The preliminary results suggest that future efforts targeting quantification of the flameless regime, which is found to be relevant in applications with larger droplets, would benefit from consideration of different possible gas-phase chemical kinetics, including cool-flame chemistry.
Statistical model for solvent oil extraction from soybean (Glycine max (L.))

Oil extraction process using hexane is common among large-scale oil industries in Nigeria. Various factors play vital roles in the quantity and quality of oil extracted from oil -bearing crops using this method. This study therefore aimed at determining the effect of flake moisture content, flake thickness and solvent temperature on oil extraction of soybean using hexane solvent in soxhlet apparatus. A 3 x 3 x 3 factorial experiment in a complete randomized design involving flake moisture content, flake thickness and solvent temperature each at three levels in three replications was adopted. The experiments were done at flake moisture contents of 4.5, 7 and 9% (wb), flake thicknesses of 0.4, 0.7 and 0.9 mm, and solvent temperatures of 60, 65 and 70°C. ANOVA using SAS software procedure was employed to determine the effect of variables on the oil extraction and a regression model for predicting oil yield on the basis of the three factors was developed using XLSTAT Microsoft Excel. The results showed that combination of 4.5% flake moisture content, 0.4 mm flake thickness and 70°C solvent temperature gave the highest oil yield (19.37%), whereas 9% flake moisture content, 0.9 mm flake thickness and 60C solvent temperature gave the lowest oil yield (14.57%). All evaluated factors have a significant effect on oil yield at 1% level. The interaction between the factors did not have a significant effect on oil yield. Model verification results gave mean square error, root mean square error, bias and accuracy of 0.084, 0.290, 0.173 and 0.030 respectively. High value of the coefficient of determination R (0.966) obtained indicated that there is a good agreement between the observed and the predicted values.
A Negative Income Tax in The Netherlands? A General and Emancipatory Point of View

Could an alternative system of income maintenance overcome the existing inequitable and inefficient situation, which effectively limits women's options in the labour market in The Netherlands? This question is approached by describing an alternative system of income maintenance in the form of a negative income tax. Both prospects and limitations of a negative income tax system for Dutch society, from the point of view of this society in general and from an emancipatory point of view in particular, are explored.