Extreme Vertices Design Research Articles

Thermal property characterization and modeling of SMAW electrode coating flux using ANN and regression analysis

The design and development of SMAW electrode coating fluxes, along with their thermal property characterization, are discussed. Using an extreme vertices design approach, 27 flux mixture combinations have been prepared. The TGA-DSC and hot disk analysis are done to quantify the thermal response of the fluxes. Results show that increase in CaF2 and SiO2 reduces weight loss. Increase in CaO increases weight loss, whereas increase in BaO shows minimal effect on weight loss. Enthalpy change of flux was found to influence mainly with CaF2 and CaO. Thermally stable flux has lower volatile compounds such as crystallization water and moisture, which helps to minimize gaseous entrapment in weld pool. An increase in CaF2 shows slight decreases and then increase in thermal diffusivity. The increase in thermal diffusivity leads to instant heat flow in the coating. Regression analysis is done, and the effect of individual and interaction of flux constituents on thermal properties is discussed. The artificial neural network is employed for predictive modeling in the domain of the mixture design approach, its prediction accuracy is compared with regression analysis. Water vapor solubility of slag was estimated between 3.169 and 3.947 and sulfide capacity of slag was − 2.479 to −1.892.

Sensory optimization of an instant brown rice cereal containing tigernut and soybean

The aim of this study was to determine the optimum ingredient formulation for an instant rice-based cereal enriched with tigernut and soybean flours. An extreme vertices design involving three (3) components (brown rice flour, tigernut flour and soybean flour) was used. A slurry of the three (3) was dried on a single drum dryer at 120 °C and 5 rpm. Mixture regression modeling was used to assess the impact of each component on the functional quality and sensory attributes properties of the drum dried product. Graphical optimization of the formulation was performed by superimposing contour plots of individual sensory attributes examined. Predicted regression models showed that tigernut flour, followed closely by rice flour, had the largest effect on overall acceptance of the product. The optimum formulation for an acceptable drum dried product was determined to be rice flour – 46.6 %, tigernut flour – 39.1 % and soybean flour – 14.3 %. The product was stable during storage, as only marginal increment was recorded in the quality attributes assessed. This study provides an avenue for enhancing the utilization potential of both brown rice and tigernut.

Tuneable solvents‐based extraction for the recovery of caffeine from coffee wastewater

AbstractTunable solvents represent a new generation of environmentally friendly solvents with potential applications in the effective extraction of bioactive compounds, including supramolecular solvents (SUPRAS). This study aimed to optimize caffeine extraction from coffee processing wastewater (CWW) using SUPRAS of various compositions. An extreme vertices design was employed to evaluate the SUPRAS composition. The synthesis of SUPRAS involved two amphiphiles (1‐hexanol and decanoic acid) in hydro‐organic solutions of tetrahydrofuran (THF). A statistical modeling approach was used to characterize the process and determine the optimal conditions for potential scale‐up within the coffee processing industry. The results indicated that SUPRAS offer a promising alternative to traditional solvents for extracting caffeine from CWW. The highest experimental extraction rate (~ 62%) was achieved using a 15% 1‐hexanol in a hydro‐organic solution of THF (47% v/v). This mixture corresponded to the optimum predicted by a special cubic statistical model (R2 = 0.9367; Adj‐R2 = 0.8608, and RSME = 3.2795). The percentage of caffeine extracted from CWW is considered acceptable, given the compound's affinity for water and the rapid (1 min) and straightforward approach employed. Moreover, the use of SUPRAS reduced solvent consumption, and the proposed statistical model identified conditions that maximized caffeine extraction while minimizing THF usage. This method can potentially lower process costs and solvent consumption. For large‐scale extraction, centrifugation can be substituted with spontaneous sedimentation. Overall, these findings have significant implications for the valorization of CWW, providing a sustainable and efficient method for the extraction of valuable compounds.

Vitrification of nuclear-contaminated HEPA filter media: A study on the viscosity-component correlation and the volatilization of simulated radionuclides

High-efficiency particulate air (HEPA) filters are commonly used in nuclear facilities for ventilation systems, which are mainly made of glass fiber. At present, the nuclear-contaminated filter media is compressed to reduce the volume and then immobilized in cement before disposal. Vitrification is a widely accepted technology in the world to immobilize nuclear wastes due to the relative simplicity of process and the excellent chemical durability of waste glass. However, the glass fiber of the filter media becomes highly viscous at the melting temperature used for nuclear waste vitrification as it contains a high concentration of SiO2 (> 50 wt%). This makes the treatment of filter media practically impossible using the existing vitrification process. Thus, in this work, emphasis has been given to the formulation of a filter media that can adapt to the existing melting process. Extreme vertices design was employed to formulate three-component (heat-treated filter mediaCaONa2O) waste glasses, and the Scheffé model was used to figure out the viscosity-component correlation of waste glasses. Moreover, the effect of each component was quantitatively determined at the temperature at which viscosity was 10 Pa·s. The volatilization experiment revealed that at 1200 °C, Co was nonvolatile, and Cs was much easier to volatilize than Sr. Furthermore, the losses of Sr and Cs during glass melting were estimated from their rates of diffusion and chemical reaction. This work would provide the fundamental basis to formulate the filter media waste glass and control the loss of radionuclides for the existing vitrification process.

Optimization and characterization of new oleogels developed based on sesame oil and rice bran oil

In recent years, there has been a surge of interest in oleogels as a promising low-saturated and trans fat free alternative to traditional solid fats. However, to date, oleogels made from different edible oils using different gelator molecules have minimum commercial application due to the lack of mimicking the properties of conventional solid fats. This study aimed to optimize the formulation of oleogels with properties close to commercial margarines based on binary mixtures of sesame oil and rice bran oil using beeswax and stearic acid as oleogelators. An Extreme Vertices Design with four components: sesame oil, rice bran oil, beeswax, and stearic acid, and 32 runs was developed using Minitab 21.1. Multi-response optimization was performed based on rheological parameters, and oil binding capacity as responses. All responses for optimization had R2 values > 96%. The oil binding capacity of the optimized oleogel was 99.99%. Optimized oleogel was further characterized for rheological, thermal, microstructural, and molecular properties and compared with commercial margarines. Results show that the properties of the optimized formula had closer values to those of commercial margarines, however with less structural recovery ability. Optimized oleogel exhibited higher oxidative stability than the margarine, however, lower than the oils. Beeswax and stearic acid exhibited synergistic effects on the oleogel properties at the ratio of 3:1. Results indicate that the optimized oleogel has the potential to be used in margarine manufacture with further developments to improve the gel strength and oxidative stability of the oleogel.

Modeling of physicochemical and thermophysical characteristics of SrO-CaO-Al2O3-CaF2-based shielded metal arc welding coating

This study investigates electrode coatings designed for use in nuclear power plant weld joints, particularly their electrical, thermophysical and physicochemical properties. The Al2O3-CaF2-CaO-SrO-based shielded metal arc welding electrodes were developed using the extreme vertices design technique. The coating composition's structure and phases were analyzed using X-ray diffraction, while Fourier transform infrared spectroscopy analysis was used to identify the types of bonds present. Advanced characterization methods were utilized to assess the coating formulations’ physicochemical, thermophysical and structural aspects. Thermal properties, including specific heat, thermal diffusivity and conductivity, were evaluated using a hot disk apparatus, while thermogravimetric analysis was employed to determine the enthalpy change and thermal stability of the flux coating. The electrical properties of the flux coatings were examined using a precision LCR instrument. Statistical analysis was employed to create regression models for each coating property to investigate the influence of mineral constituents on the flux coating properties. Regression analysis is a statistical method used to establish a relationship between mineral interactions. In flux composition selection, it can help determine the physical significance of each factor and its relationship with the coating's performance. The results indicate that the mineral constituents’ individual elements, binary and tertiary interactions, significantly impact the flux composition's physicochemical, electrical and thermophysical properties.

Applicability of Extreme Vertices Design in the Compositional Optimization of 3D-Printed Lightweight High-Entropy-Alloy/B4C/ZrO2/Titanium Trihybrid Aero-Composite

Recent studies have shown the benefits of utilizing ceramic particles as reinforcement in metal alloys; nevertheless, certain drawbacks, including loss of ductility, embrittlement, and decreases in toughness, have been noted. For the objective of obtaining balanced performance, experts have suggested the addition of metal particles as supplement to the ceramic reinforcement. Consequently, high-performance metal hybrid composites have been developed. However, achieving the optimal mix for the reinforcement combination with regards to the optimal performance of developed composite remains a challenge. This research aimed to determine the optimal mixture of Al50Cu10Sn5Mg20Zn10Ti5 lightweight high-entropy alloy (LHEA), B4C, and ZrO2 for the fabrication of trihybrid titanium composites via direct laser deposition. A mixture design was involved in the experimental design, and experimental data were modeled and optimized to achieve the optimal performance of the trihybrid composite. The ANOVA, response surface plots, and ternary maps analyses of the experimental results revealed that various combinations of reinforcement particles displayed a variety of response trends. Moreover, the analysis showed that these reinforcements significantly contributed to the magnitudes and trends of the responses. The generated models were competent for predicting response, and the best formulation consisted of 8.4% LHEA, 1.2% B4C, and 2.4% ZrO2.

Investigation and modeling of the SMAW coating flux thermal properties using neural network and regression analysis

The present work aims to design and develop shielded metal arc welding electrode coating fluxes. The thermal properties of the electrode coating fluxes are studied. Ternary phase diagrams of CaF2−CaO−Al2O3 and SiO2−BaO−Al2O3 are used to determine the range of constituents. 27 flux mixture combinations were created using an extreme vertices design approach. The corrected optical basicity is estimated and utilized for the theoretical estimation of sulfide capacity and water vapor solubility. Thermogravimetric analysis, and differential scanning calorimetry analysis was performed to quantify the thermal response of the flux while heating. Thermogravimetry analysis shows variation of weight loss from 8.49% to 12.25% with the variation in flux composition. Calcite and witherite has positive influence on weight loss. Differential scanning calorimetry shows an overall change in enthalpy from −1076.73 to −7786 J/g. Hot disk analysis reveals fluorspar has a positive effect, whereas calcite has a negative effect on thermal conductivity. The effect of individual flux constituents and their interactions on thermal properties is discussed using regression analysis. The artificial neural network is used for predictive modeling, and the accuracy of its predictions is compared to regression analysis. In comparison to the regression, the model's mean square error improved by nearly 37% on average. The reduction in the mean absolute percentage error of the unseen test data suggests that the artificial neural network approach has better modeling capability.

Investigation of Thermophysical and Physicochemical Characteristics of Al2O3-SiO2- CaO - Na3AlF6 Flux for SMAW Electrode Coating

This study investigated the thermophysical, physicochemical, and electrical characteristics of electrode coatings developed for application in the weld joint of nuclear power plants (NPPs). The extreme vertices design technique has been used in this work to develop the Al2O3-SiO2-CaO-Na3AlF6-based Shielded metal arc welding (SMAW) electrodes. Twenty-six electrode coating compositions were formulated, and flux coatings were milled into a fine powder for further characterization. X-ray diffraction (XRD) technique was utilized to investigate the structure and phases of the coating composition, and the Fourier transform infrared (FTIR) analysis technique was employed to determine the nature of bonds. The coating's thermal characteristics, including conductivity, diffusivity, and specific heat, were evaluated using hot disk equipment. Enthalpy change and thermal stability of flux coating were determined using the Differential thermal analysis(DTA)/ differential scanning calorimetry (DSC) technique.. The precision inductance (L), capacitance (C), and resistance (R) (LCR) instrument was used further to examine the electrical characteristics of the flux coatings. In addition, a regression model has been developed for each coating property using statistical analysis and investigated a correlation between the properties and mineral interactions. Results reveal that the individual elements and their binary and tertiary interaction significantly influence the physicochemical, thermophysical, and electrical properties of the flux coatings.

Wettability studies of formulated SMAW electrode coating fluxes with regression analysis and neural network approach

The present work aims to formulate and investigate the SMAW electrode coating fluxes for pipeline steels. The wettability of the flux on steel has a significant influence on weld properties. Twenty-seven flux compositions are produced by the extreme vertices design approach. The contact angle, spread area, work of adhesion, and floatation coefficient at 1573 K are investigated for the SiO2−CaO−CaF2−BaO−Al2O3−TiO2 fluxes. The corrected optical basicity and surface tension of the fluxes are estimated. The XRD, FTIR, and UV–vis analysis techniques are employed to investigate the phases present in the flux and slag. The structural analysis of the melt is done by examining the powder of quenched slag. The corrected optical basicity is estimated, which is a global measure of oxygen species in the melt. Regression models are developed to study the effect of flux composition on the wettability properties. An artificial neural network method is used, and the MSE and MAPE values for the predicted result have been successfully lowered.

Quality assessment of baby wet wipes

A wet wipe is a commercial product made of a fibrous substrate impregnated with a lotion that often comes folded and individually wrapped for convenience. The present work relates to wet wipes’ composition to clean the baby’s body. Wet wipes were produced from two spunlace nonwoven fabrics consisting of polyester/viscose and a wetting solution. Objective performance evaluation was carried out to determine the efficiency of the wipes for manufacturing and end uses. The lotion formula comprising surfactants, a solubilizer, preservative compounds, perfumes, and mainly purified water is selected to deliver the intended benefits of a baby wet wipe. Besides, physical, mechanical characteristics, and moisture management parameters of the wet wipe fabrics were measured. Optimal lotion (oil–water emulsion) stirring conditions were illustrated using optical microscopy. Lotion foamability appears as an undesirable phenomenon upon the manufacturing of the wet wipe. A mixture design, an extreme vertices design, was used to study the influence of the compounds on the foam volume. The relative contribution of each compound in the lotion to generate bath foam was discussed. Because wet media are more effective than dry media for surface cleaning, the optimum wet pick-up ensuring the best wiping efficiency about of 83.2% was found to be about 3 g of lotion for 1 g of fabric. Assuming that a wipe sample could be performed in less than 3 min, it was also confirmed that the developed wipe remains effective with a moisture content of 242% and can be comparable with other commercial wipes.

Formulation and optimization of a phosphogypsum – fly ash – lime composite for road construction: A statistical mixture design approach

This paper investigates the valorization of phosphogypsum and fly ash by-products as a road construction material through lime stabilization. To this end, an extreme vertices design was adopted to model the compaction characteristics, mechanical performance at different curing periods and durability upon wetting/drying (W/D) cycles of the mixture. Statistical analysis of the obtained regression models showed that the measured responses decrease with phosphogypsum addition while fly ash and lime cause them to increase. The increasing effect of fly ash addition was especially noticeable on compressive strengths at early ages (7–28 days), whereas at longer curing periods (90–360 days), these were mainly governed by its interaction with lime following the activation of the pozzolanic reaction where phosphogypsum acted as a catalyst to improve fly ash reactivity. However, a negative impact of excess lime beyond a threshold has been noted. The compressive strength at 28 days combined with weight loss upon W/D cycles were used as optimization responses to detect regions of interest, within the design space, where requirements are met for a subbase utilization.

Pasting Behavior and Viscoelastic Properties of Fresh, Chilled, and Rehydrated Freeze-Dried Gel Beads from Blends of Tapioca Flour, Soy Flour, and Cane Sugar

Abstract An extreme vertices design for a mixture of three components was used to establish the proportions of tapioca flour (50% to 100% w/w), soy flour (0% to 50% w/w), and cane sugar (0% to 10% w/w) mass fractions in a food gel bead system. Thus, nine compositions were prepared and analyzed. The pasting profiles of the mixtures were studied using a Rapid Visco Analyzer. The texture profiles of fresh, chilled, and rehydrated freeze-dried gel beads were studied using a texture analyzer. Increasing the proportion of soy flour in the range of 11.25% to 50.00% w/w decreased the peak viscosity, breakdown, final viscosity, and setback of mixed flour. Tapioca flour in the proportion of 81.25% to 100.00% w/w recorded the lowest hardness of fresh gel beads (92.00 to 283.00 g). Soy flour in the proportion of 11.25% to 50.00% w/w exhibited lower texture profiles (hardness, chewiness, and gumminess) than tapioca flour in gel beads for both chilled and rehydrated freeze-dried gel beads. Significant relationships were found among pasting profiles of the flour mixtures and texture profiles of fresh, chilled, and rehydrated freeze-dried gel beads, implying a functional role for soy flour in food gel beads. In conclusion, soy flour can act as an anti-retrogradation agent for the gel beads both in chilled (stored at 4°C for 7 days) and freeze-dried conditions. A small amount of cane sugar does not affect the inhibition of starch retrogradation in the gel bead system. Keywords: Anti-retrogradation, Food gel bead, Pasting profile, Soy flour, Tapioca flour, Texture profiles

Antibacterial activity of grapefruit peel extracts and green-synthesized silver nanoparticles.

Background and Aim:The gradual loss of efficacy of conventional antibiotics is a global issue. Plant material extracts and green-synthesized nanoparticles are among the most promising options to address this problem. Therefore, the aim of this study was to assess the antibacterial properties of aqueous and hydroalcoholic extracts of grapefruit peels as well as their inclusion in green-synthesized silver nanoparticles (AgNPs).Materials and Methods:Aqueous and hydroalcoholic extracts (80% v/v) were prepared, and the volume and mass yields were determined. The synthesis of AgNPs was done in an eco-friendly manner using AgNO3 as a precursor. The nanoparticles were characterized by ultraviolet–vis spectrometry and photon cross-correlation spectroscopy. The antibacterial activity of the extracts was tested on three Gram-positive bacteria (Staphylococcus aureus ATCC 6538, clinical Enterococcus faecalis, and S. aureus) and two Gram-negative bacteria (two clinical Escherichia coli) using various concentrations of extracts (100, 50, 25, 12, and 5 mg/mL and 5% dimethyl sulfoxide as negative control). Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using the microdilution method. Modulation of cefazoline and ampicillin on resistant E. coli and S. aureus strains was added to the mixture design response surface methodology with extreme vertices design, with the diameters of inhibition and the fractional inhibitory concentration index as responses and factors, respectively. The antibiotic, the ethanolic extract, and water varied from 0.1 MIC to 0.9 MIC for the first two and from 0 to 0.8 in proportion for the third. Validating the models was done by calculating the absolute average deviation, bias factor, and accuracy factor.Results:The volume yield of the EE and aqueous extract (AE) was 96.2% and 93.8% (v/v), respectively, whereas their mass yields were 7.84% and 9.41% (m/m), respectively. The synthesized AgNPs were very uniform and homogeneous, and their size was dependent on the concentration of AgNO3. The antibacterial activity of the two extracts was dose-dependent, and the largest inhibition diameter was observed for the Gram-positive bacteria (S. aureus ATCC 6538; AE, 12; EE, 16), whereas AgNPs had a greater effect on Gram-negative bacteria. The MICs (mg/mL) of the AEs varied from 3.125 (S. aureus ATCC 6538) to 12.5 (E. coli 1 and E. coli 2), whereas the MICs of the EEs varied from 1.5625 (S. aureus 1, S. aureus ATCC 6538, and E. faecalis) to 6.25 (E. coli 1). There was a significant difference between the MICs of AEs and EEs (p=0.014). The MBCs (mg/mL) of the AEs varied from 12.5 (S. aureus ATCC 6538) to 50 (S. aureus 1), whereas those of the EEs varied from 6.25 (S. aureus 1) to 25 (E. coli 1 and E. faecalis). Ethanolic grapefruit extracts demonstrated an ability to modulate cefazolin on E. coli and S. aureus but were completely indifferent to ampicillin on E. coli.Conclusion:Grapefruit peel extracts and their AgNPs exhibit antibacterial properties that can be exploited for the synthesis of new antimicrobials and their EEs may be efficiently used synergistically with other antibiotics against bacteria with intermediate susceptibility.

CaO–CaF2–SiO2–Al2O3 system for development of SMAW electrodes with Ni alloy core wire

This research investigates the effect of CaO–CaF2–SiO2–Al2O3 based flux coating constituents of nickel-based electrodes on the weld chemistry of power plant applications. Extreme vertices design approach was used to prepare electrode coatings and extruded on FM-182 (Nickel based) core wire. TiO2 is added in a fixed amount to enhance the arc stability during welding and slag detachability. Weld beads were deposited on P22 alloy steel plate and examined for weld chemistry in terms of Cr, Ni, Nb and Fe. The microhardness of the deposited welds was also observed using Vicker's microhardness tester. Regression analysis was applied to develop a relationship between the weld chemistry and flux constituents. The results obtained from the regression analysis were then optimized to choose the best suitable electrode coating composition with higher desirability.

Laser welding 6061 aluminum alloy with laser cladding powder

To solve the problem of low absorption and welding surface collapse in the laser welding of the 6061 aluminum alloy, the powder was first added to the surface of the weld by laser cladding. The effect of laser cladding powder type on the microstructure and hardness of the 6061 aluminum alloy was studied. The results show that laser cladding of single Al powder, Si powder, and Ni powder can all improve laser absorption during laser welding of aluminum alloy, but each material has specific limitations, such as reducing the number of strong phases, generating other phases, and the nonevening of phases. Two kinds of mixed powder, Al:Si and Al:Ni, can overcome these limitations to a certain extent. Laser cladding with three kinds of mixed powder resulted in a better welding effect than when using two kinds of mixed powder or a single powder. By applying an extreme vertices design, the optimum ratio of Al-Si-Ni powder was determined as 0.737:0.185:0.078, resulting in the uniform microstructure of the weld without delamination. The mechanical properties test shows that the hardness of the laser cladding with powder was better than that without laser cladding powder, and the tensile strength of the weld was 83% of the base material.

Enabling Oral Amphotericin B Delivery by Merging the Benefits of Prodrug Approach and Nanocarrier-Mediated Drug Delivery.

Amphotericin B (AmB) is gold standard therapy for leishmaniasis and fungal infections. Considering the global disease burden, nearly 90% of cases occur in economically vulnerable countries, making the cost of AmB therapy a critical healthcare challenge in controlling disease burden. All currently marketed AmB products are administered through an intravenous (i.v.) route and involve high treatment costs. Designing an orally effective AmB formulation can substantially reduce the cost of therapy and improve patient compliance. However, it is a challenging task because of the distinctive physicochemical properties of AmB. Previously, we developed a lipid-based prodrug of AmB, AmB-oleyl conjugate (AmB-OA), which showcased remarkable stability in the gastrointestinal (GI) environment and improved intestinal permeation. Hereby, we have developed self-nanoemulsifiying drug delivery system (SNEDDS) of AmB-OA to further enhance the oral bioavailability of AmB and potentiate its therapeutic benefits. SNEDDS was developed by screening a wide range of oils, surfactants, and cosurfactants, and formulation composition was optimized using extreme vertices design. AmB-OA SNEDDS possessed the ability of quick self-nanoemulsification on dilution (droplet size ∼56 nm) along with remarkable stability in the GI environment. Accelerated stability (40 °C/75% relative humidity) studies and freeze-thaw cycling studies proved that the formulation was stable at tropical conditions as well as temperature cycling stress. Drug transport analysis in Caco-2 cells revealed a remarkable increase in drug transport for AmB-OA SNEDDS compared to AmB along with minimal cellular toxicities. AmB-OA SNEDDS showcased ∼8.9-fold higher AUCTot than AmB in in vivo pharmacokinetic study, proving the effectiveness of formulation to enhance oral bioavailability. In vivo toxicity analysis highlighted the ameliorated toxicity risk associated with SNEDDS formulation. Therefore, the AmB-OA SNEDDS formulation may provide a cost-friendly and effective strategy to resolve the oral AmB drug delivery challenge.

Investigations on effect of CaO-CaF2-TiO2-SiO2 based electrode coating constituents and their interactions on weld chemistry

This paper reports on the effect of CaO-CaF2-TiO2-SiO2 based electrode coating constituents and their binary, tertiary interactions on the weld metal chemistry of offshore structure. Coating compositions were prepared based on extreme vertices design methodology and extruded on austenitic 309L filler wire. Red ochre, a mineral waste from iron ore site, has been added to coating compositions in uniform quantity to utilize its iron content. Multi-pass weld beads hence deposited on super duplex 2507 grade steel were examined for chemical composition in terms of phosphorus, sulphur, molybdenum, niobium, and iron. Regression analysis was carried out to develop a relationship between the chemical composition and coating constituents, quantifying the effect of interactions. Obtained responses have also been optimized to find the most suitable coating compositions in the desired range of mineral constituents. The developed electrode coatings have been analyzed for their microstructure using scanning electron microscopy equipped with an energy dispersion spectroscope. The work establishes a relation between the coating minerals and their interactions on the weld chemistry.

Effect of emulsion formulation on characteristics of pea protein-stabilized oil-in-water emulsions

The goal of this study was to investigate the effect of emulsion formulation on characteristics of oil-in-water emulsions. Varying concentrations of biopolymers including maltodextrin, gum arabic and pea protein were used in the formulation of emulsions created according to an extreme vertices design. Mean droplet size of oil-in-water emulsions changed between 0.9-2.5 µm and decreased with increasing pea protein concentration. Creaming stability ranged between 9-100% and increased as the concentration of pea protein increased. The results of this research suggest that pea protein can be utilized as an emulsifier for oil-in-water emulsions with low oil concentration as it has the ability to decrease the mean droplet size and increase creaming stability of the emulsions.

Optimized utilization studies of dredging sediment for making water treatment ceramsite based on an extreme vertex design

The minimal recycling and large accumulation of dredging sediment has resulted in a range of social and environmental problems. To solve the residual sediment disposal problems, a series of experiments utilizing the dredging sediment as ceramsite components were performed. Zeolite and bentonite were introduced as additives. In this work, the extreme vertices design method was used to determine the optimal proportion of a three-component mixture for sintering sediment ceramsite. The results showed that the maximum specific surface area of 51.68 m2/g and the largest porosity of 53.93% could be achieved with the optimal contents of 40.30 wt.% sediment, 39.42 wt.% zeolite, and 20.28 wt.% bentonite. The characterizations (mineralogical characteristics, physical characteristics, microstructure characteristics, and toxic metal leaching characteristics) of the sediment ceramsite were measured. The property tests of the sediment ceramsite showed that the dredging sediment played an important role in the sintering process of the ceramsite. The heating process can be divided into three stages, and the main new crystalline phases of the sediment ceramsite were clinoptilolite (Na(AlSi5O12)·4H2O), albite-calcian ordered (NaCaAl(SiAl)2O8) and quartz (SiO2). The sediment ceramsite presented a rough surface and had an abundant porous structure with elongated and interconnected pores (diameters between 0.05 and 10 μm). Additionally, the sediment ceramsite was verified to meet the standard of lightweight ceramsite (bulk density was 0.89 g/cm3) and was macroporous (the mean pore size was 3.3472 μm), nontoxic (concentrations of toxic metal leaching were all below the industry standard) and suitable for the water treatment system.