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Fura is a traditional thick dough ball snack produced principally from millet or sorghum which is common in Nigeria. It is consumed with nono (local fermented milk) or mashed in water before consumption in the form of porridge. The purpose of this paper is to study the optimization of feed composition, feed moisture and screw speed on acceptability and hydration properties of fura extrudates from pearl millet and soybean flour mixtures.

The effects of extrusion conditions feed composition (ratio of soybean to millet), percentage moisture wet basis and screw speed (rpm) on the hydration properties and the acceptability of fura from millet‐soybean flour mixtures were studied using a single screw extruder. Response surface methodology (RSM) was adopted to evaluate the hydration properties responses of fura extrudates.

The models showed R²=0.863, 0.825, 0.898 and 0.741 for hydration power (HP), effect of quantity of water on swell volume (EQWSV), wettability (WTBLTY) and viscosity respectively indicating that the model was a good fit and could be used to navigate the design space. The result indicates that increasing the level of soybean flour resulted in decreased HP of fura extrudates. The overall acceptability sensory scores show that the fura extrudate design point 11 representing 20 percent soybean, 16.6 percent feed moisture and 200rpm recorded the highest acceptability (7.25) with significant differences from the other extrudates in terms of colour, flavor, texture and overall acceptability.

The extrusion cooking data from this study could help predict the expected performance in investigations of potential use of millet and soybean to explore the possibility of industrial projection.

The paper aims to throw light on the interactions taking place between the different chemical compositions at various temperatures. P-methylacetophenone is a polar dissolvable, which is positively related by dipole–dipole co-operations and is exceptionally compelling a direct result of the shortfall of any critical primary impacts because of the absence of hydrogen bonds; hence, it might work an enormous dipole moment (μ = 3.62 D). Alcohols additionally assume a significant part in industries and research facilities as reagents and pull in incredible consideration as helpful solvents in the green innovation. They are utilized as pressure-driven liquids in drugs, beauty care products, aromas, paints removers, flavors, dye stuffs and as a germ-free specialist.

Mixtures were prepared by mass in airtight ground stopper bottles. The mass measurements were performed on a digital electronic balance (Mettler Toledo AB135, Switzerland) with an uncertainty of ±0.0001 g. The uncertainty in mole fraction was thus estimated to be less than ±0.0001. The densities of pure liquids and their mixtures were determined using a density meter (DDH-2911, Rudolph Research Analytical). The instrument was calibrated frequently using deionized doubly distilled water and dry air. The estimated uncertainty associated with density measurements is ±0.0003 g.cm⁻³. Viscosities of the pure liquids and their mixtures were determined by using Ostwald’s viscometer. The viscometer was calibrated at each required temperature using doubly distilled water. The viscometer was cleaned, dried and is filled with the sample liquid in a bulb having capacity of 10 ml. The viscometer was then kept in a transparent walled water bath with a thermal stability of ±0.01K for about 20 min to obtain thermal equilibrium. An electronic digital stop watch with an uncertainty of ±0.01 s was used for the flow time measurements for each sample at least four readings were taken and then the average of these was taken.

Negative values of excess molar volume, excess isentropic compressibility and positive values of deviation in viscosity including excess Gibbs energy of activation of viscous flow at different temperatures (303.15, 308.15 and 313.15 K) may be attribution to the specific intermolecular interactions through the hetero-association interaction between the components of the mixtures, resulting in the formation of associated complexes through hydrogen bond interactions.

The excess molar volume (V^E) values were analyzed with the Prigogine–Flory–Patterson theory, which demonstrated that the free volume contribution is the one of the factors influencing negative values of excess molar quantities. The Jouyban–Acree model was used to correlate the experimental values of density, speed of sound and viscosity.

The purpose of this paper is to study analytically and numerically the effect of a transverse magnetic field on the separation of species induced in an inclined rectangular porous cavity saturated with an electrically conducting mixture.

The porous layer is assumed homogeneous and submitted from its long sides to uniform heat fluxes and to a magnetic field of strength B. The Darcy model combined with the Boussinesq approximation are used to study the heat and solute transfer in the medium. An analytical solution is developed on the basis of the parallel flow approximation. Numerical simulations are also performed in order to validate the analytical solution. The controlling parameters of this problem are the thermal Rayleigh number, the inclination of the enclosure, the separation parameter, the Hartmann number and the Lewis number.

For given values of the thermal Rayleigh number, the inclination of the enclosure, the separation parameter and the Lewis number, there is an optimal magnetic field which leads to a maximum of separation. At relatively high Rayleigh numbers, where convection destroys the separation process, it is possible, with an optimal choice of the Hartman number, to recover a good level of separation.

Since the problem is governed by several parameters (five parameters), only the Darcy model was used in this study instead of the Darcy-Brinkman extended model even if the latter model allows to cover the pure fluid and Darcy porous media as limiting cases.

In separation experiments, it is very difficult technically to work with small Rayleigh numbers due to technical difficulties. However, the process of separations is canceled at high Rayleigh number by the strength of convection which causes a mixing in the binary mixture. This study shows that, by using adequate combinations of the controlling parameters, it becomes possible to reach a good level of separation even at relatively high Rayleigh numbers.

Optimum choice of the magnetic field and the inclination of the cavity may lead to a good level of the separation process. For large Lewis numbers, the separation vanishes far above and far below the optimal Ha. However, for small Lewis numbers, an important level of separation is maintained for any Ha located below the optimal value of the latter parameter.

By its high fluidity, great deformability and rheological stability, the self-compacting mortar (SCM) is capable of ensuring the ability to be easily implemented without vibration. However, its formulation requires a large volume of fine materials with a high dosage of cement, which is necessary to ensure adequate workability and mechanical strengths, which is necessary to allow its flow. Current environmental considerations encourage reducing the production of cement, it is essential to use additions to replace the cement, because of their great availability and their moderate price. On another side, their use contributes to an economic sort to solve the problems related to the environment.

The formulations and characteristics of SCM made with two types of mineralogical sources (silica and limestone) were investigated. Different materials were used separately and in binary combinations; silica river sand (SRS), limestone quarry sand (LQS), silica fillers (SF) and limestone fillers (LF). The formulation starts with the self-compacting pastes (SCPs) then the SCMs at the SRS and the LQS whose the cement is partially replaced by volume contents of SF and LF with 15%, 30% and 45%.

The results obtained prove that the incorporation of LQS instead of SRS has a negative effect on the fluidity and deformability and a positive effect on the mechanical strengths of SCM. In addition, the incorporation of the SF and LF reduces the need for water and the saturation dose of superplasticizer in the pastes. Thus, the addition of the SF and LF in specific voluminal contents (15% SF and 30% LF) in the binder can have a beneficial effect on the parameters of the workability and the mechanical strengths of SCM. These results are very interesting to aspects such as technological, economic and environmental.

Influence of the different type of sands and fillers in improvements the properties of SCM made from various mineralogical sources.

The purpose of this paper is to present a numerical and an analytical study of the thermohaline convection with Soret effect in a square enclosure filled with a binary fluid mixture.

The horizontal boundaries of the enclosure are impermeable and heated from below while its vertical walls are assumed to be adiabatic and impermeable. The Navier‐Stokes equations under the Boussinesq‐Oberbeck approximation are solved numerically. The results are given for different values of the separation ratio. The critical Rayleigh number at the onset of convection is determined analytically and numerically. The Hopf frequency at the onset of convection is obtained.

The existence of two stable stationary bifurcation branches is illustrated. Furthermore, it is shown that the existence of stable traveling waves in the transition from one branch to the other depends on the value of the separation ratio. For some values of Rayleigh number, asymmetric flows are observed. A good agreement is found between the numerical solution and analytical analysis.

The present work is the first to consider thermosolutal convection with Soret effect in a square enclosure.

A prototype gas prover was constructed to serve as the Italian primary standard for gas flow rates in the range 0.1 ml/min to 2 l/min. The new prover is used to calibrate high‐quality industrial standards, as well as the MFCs used in microelectronic fabrications and preparation of reference gas mixtures.Design/methodology/approach – The prover measures gas volume transfers caused by displacements of a 120 mm dia. motor‐operated piston, which is introduced into a temperature‐controlled chamber containing up to 3 l of the required working gas at near ambient conditions. Gas delivery is made at constant rate, whereas possibly variable incoming flows are measured at constant pressure. Displacements of the piston are measured by an optical interferometer.Findings – The analysis shows that standard uncertainty ranges between 0.013 and 0.03 percent. Owing to the very accurate control and measurement of both pressures and temperatures, these figures refer equally to volume and mass flowrate. Experimental comparisons with similar national standards at LNE‐France and NIST‐USA confirmed the consistency of measurement results in the three Nations.Research limitations/implications – The gas prover should be used with inert gases only.Practical implications – The national industrial gas standards and the best flow transducers can now be calibrated accurately down to unprecedented flowrate values.Originality/value – The need for measurement of extremely low gas flows is quite recent, therefore possibly less than ten primary national standards are available today worldwide. Several completely different principles and designs have been developed; description of design and performance of each instrument is important to assess their respective merits. The described apparatus is innovative as regards measurement range, accuracy and control techniques.

The purpose of this paper is to use Amazon River shrimp meal and cassava flour as the raw materials for the production of an extruded product. Both these raw materials are highly consumed foods in the northern region of Brazil, but are not processed industrially, only being used for local consumption and there is little in the literature concerning their use.

The study was carried out using a full 23 factorial central composite rotational experimental design with three independent variables, which were shrimp meal; feed moisture content and temperature, with four replicates at the central point and six axial points. The dependent variables were: expansion index (EI), bulk density (BD) and specific length (SL). The principal component analysis (PCA) was applied for the sensory analysis.

Almost all the parameters studied had a significant influence (p<0.10) on the responses analysed. The product was well accepted by 78.11 per cent of the volunteers. Increases in the shrimp meal and feed moisture contents strongly influenced the physical analyses (EI, BD and SL) of the extruded product. In the application of the PCA for the sensory analysis, the influence of the variables aroma, appearance and purchase intention corresponded to PC1, and that of the variables flavour, texture, global acceptance and colour to PC2.

The development of a product based on animal protein which is more available than common snacks, as a way of reducing the negative environmental impact caused by the disposal of Macrobrachium amazonicum, which is considered as accompanying fauna to artisan fishery.

The originality of this paper lies in the quest for the development and/or application of technologies that allow for the use of raw materials from the Amazon as a way of aggregating value to the existing wealth of this region.

The purpose of this paper is to identify the strain of oyster mushroom (OM) Pleurotus sapidus cultivated in a local (commercial) farm, and to generate a total quality index (TQI) on the strain using different modified atmosphere packaging (MAP) gas mixtures.

A phylogenetic tree was constructed using the MEGA software to identify the specific strain of P. sapidus grown in a local farm. The effects of MAP on fresh fruiting bodies of the identified strain were determined under three conditions: high carbon dioxide packaging (HCP: 20 per cent CO₂, 15 per cent O₂), low carbon dioxide packaging (LCP: 2 per cent CO₂, 30 per cent O₂) and high nitrogen packaging (HNP: 85 per cent N₂, 15 per cent O₂). All samples were stored at 4 ^oC for up to ten days, and subjected to total phenolic content (TPC), colour retention (CR) and sensory analysis. Quality parameters such as chewiness and odour were used to obtain the TQI.

From the phylogenetic analysis, a new strain (P. sapidus strain QDR) with 99 per cent similarity to P. sapidus was identified. Among the three MAP treatments, HCP recorded the highest TPC (2.85 mg GAE/g) and CR (60.36) after ten days, although only its CR was significantly different (p<0.05) from the control. Feedback from 30 sensory panellists indicated that both HCP and LCP were generally more effective in retaining the colour–odour of OM. The optimum TQI for HCP was obtained based on the observed parameters, which is useful for the large-scale packaging of OM.

Scientific evidence has revealed that packaging trend for commercially grown OM affects consumer’s acceptance.

The purpose of this paper is to explore the variety of food in which it has been applied as a prebiotic and functional ingredient, the concentrations used there in, the tests that have been conducted on these fortified foods and briefly reviews the history and characteristics of inulin.

The review included articles from 1999-2013. The papers which reported inulin concentrations used, the purpose of the application and tests on final product, were mainly selected. Articles were collected in electronic databases such as Elsevier-Science Direct, Emerald, Springer Link, Wiley and Redalyc.

The interaction inulin-food with different food matrices is complex, and is not always technologically favorable for the product. Moreover, additional to evaluations of sensory, physicochemical and rheological characteristics, it is essential to carry out measurements in the food, of such characteristics as prebiotic content, and prebiotic activity in vivo and in vitro, and assess potential adverse reactions in order to define suitable doses of consumption.

The paper highlights the importance of conducting in vitro and in vivo testing of potential prebiotic inulin-supplemented food in order to define dose that benefit health and do not cause unacceptable gastrointestinal distress.

The purpose of this study is to contribute with experimental study of the effects of binary and ternary combinations of river sand (RS), crushed sand (CS) and dune sand (DS) on the physical and mechanical performances of self-compacting concrete (SCC) subjected to acidic curing environments, HCl and H₂SO₄ solutions.

Five SCCs were prepared with the combinations 100% RS, 0.8RS + 0.2CS, 0.6RS + 0.2CS + 0.2DS, 0.6RS + 0.4DS and 0.6CS + 0.4DS. The porosity of sand, fluidity, deformability, stability, compressive strength and sorptivity coefficient were tested. SCCs cubic specimens with a side length of 10 cm were submerged in HCl and H₂SO₄ acids, wherein the concentration was 5%, for periods of 28, 90 and 180 days. The resistance to acid attack was evaluated by visual examination, mass loss and compressive strength loss.

The results showed that it is possible to partially substitute the RS with CS and DS in the SCC, without strongly affecting the fluidity, deformability, stability, compressive strength and durability against HCl and H₂SO₄ attack. The two combinations, 0.8RS + 0.2CS and 0.6RS + 0.2CS + 0.2DS, improved the compactness and the resistance to acid attacks of SCC. Consequently, the improvement in SCC compactness, by the combination of RS, CS and DS, decreased the sorptivity coefficient of SCC and increased its resistance to acid attacks, in comparison with that made only by RS.

The use of RS is experiencing a considerable increase in line with the development of the country. To satisfy this demand, it is necessary to substitute this sand with other materials more abundant. The use of locally available materials is a very effective way to protect the environment, improve the physico-mechanical properties and durability of SCC and it can be a beneficial economical alternative. Few studies have addressed the effect of the binary and ternary combination of RS, CS and DS on the resistance to acid attacks of SCC.