Simplex-centroid Design Research Articles

Early hydration and compressive strength of steam cured high-strength concrete based on simplex centroid design method

To obtain the precast concrete elements with high strength at an early stage, and strike a balance among mechanical properties, economic benefits and sustainable development. The heat of hydration, bound water content, calcium hydroxide content (CH), compressive strength and porosity of high-strength concrete (HSC) with cement–silica fume–fly ash micro-bead binder at 85 °C were investigated. The ternary binder formulations were the designed using simplex centroid design method. The results show that the appropriate amount of silica fume and fly ash micro-bead increases the total heat release and compressive strength of HSC, and reduce the CH content and porosity. Silica fume incorporation advances the induction period end time, while fly ash micro-bead increases the induction period end time. The pozzolanic reactivity of silica fume was greater than that of fly ash micro-bead. The effect of silica fume on 28 days strength was particularly obvious, and fly ash micro-bead have more significant improvement in early strength. The porosity shows a strong correlation with the compressive strength. The findings of this study are a worth reference for precast concrete manufacturers and can help to guide future studies.

Combination of mixed mode dispersive solid phase extraction with magnetic ionic liquids based dispersive liquid–liquid microextraction for the extraction of anticoagulant drugs from urine samples

In this report, combination of a mixed mode dispersive solid phase extraction with dispersive liquid–liquid microextraction has been performed in order to the effective isolation of three anticoagulant drugs (anagrelide, betrixaban, and apixaban) from urine sample. The extracted drugs were quantified by high performance liquid chromatography–diode array detector. Firstly, analytes were adsorbed onto a mixture of octadecylsilane, graphitized carbon black, and primary secondary amine sorbents which their composition was obtained by a simplex centroid design. To increase the adsorption efficiency, sonication of the solution and sorbents mixture was performed. The loaded analytes onto the sorbent surface were washed employing a water–miscible organic solvent which was utilized as a disperser in microextraction process. The microextraction step was done using a magnetic ionic liquid (as an extractant) and the droplets were sedimented at the bottom of tube with the aid of an external magnetic field. Satisfactory analytical results such as wide linear ranges (0.21–250 µg/L), high enrichment factors (223–247) and extraction recoveries (76–84 %), and low limits of detection (0.04–0.06 µg/L) and quantification (0.16–0.21 µg/L) were obtained using the optimum experimental situations. Lastly, the offered procedure was utilized for the quantification of the opted analytes in urine samples.

Effects of coarse aggregate morphology on concrete mechanical properties

The morphology of coarse aggregate can significantly affect the mechanical performance of concrete. In this study, the correlation between the compressive properties of concrete and the coarse aggregate morphology was systematically explored. Three kinds of aggregates with significant morphology differences were selected: Spherical Aggregates, Flaky Aggregates, and Elongated Aggregates. Three-dimensional morphological information was obtained by 3D Structured-Light Scanner, and quantitative statistical analyses were conducted to assess the distribution of morphological characteristics for these three-types aggregates. It is found that the three-type aggregates with the same mesh size can be properly discriminated through the axis length, flatness, elongation, the product of flatness and elongation, and sphericality. The simplex-centroid design was used to build the correlation between aggregate morphology and the compressive strengths of concrete with different water-cement ratios. The concrete with 100% spherical aggregates owns the highest compressive strength, which is higher than that of concrete mixed with other two aggregates by 9.4%–36.2% and 5.2%–28.8% at the curing of 3-day and 28-day, respectively. When the ratio of spherical aggregates reaches above 50%, the strength loss caused by the elongated aggregates and flaky aggregates content is not obvious. Further, the failure mechanism of concrete with 100% spherical aggregates, 100% flaky aggregates, and 100% elongated aggregates under cyclic loadings were investigated by X-ray computed tomography scanning. It is found that the cracks inside spherical aggregates concrete mainly initiate from the edges and the core section remains almost intact before the destruction by a major oblique crack. Meanwhile, the high residual strain after cyclic loadings can originate from the generated vertical cracks under compression. The research findings in this study can serve as a solid base for the designing of concrete structures.

Entrapment of magnetic nanoparticles into poly(divinylbenzene-co-N-vinylpyrrolidone) copolymer for the determination of prohibited and restricted fragrance ingredients in cosmetic products

In this work, a magnetic composite made by cobalt ferrite (CoFe2O4) magnetic nanoparticles entrapped into a poly(divinylbenzene-co-N-vinylpyrrolidone) copolymer is used to determine recently prohibited and restricted fragrances (i.e., Lilial, Lyral, and methyl-N-methylanthranilate) in cosmetics. This hydrophilic-lipophilic balance type material was characterized by magnetism measurements, scanning electron microscopy, nitrogen adsorption–desorption isotherms, and thermogravimetric analysis. The proposed method is based on stir bar sorptive dispersive microextraction (SBSDME) followed by gas chromatography coupled to mass spectrometry (GC–MS). The main quantitative parameters involved in the SBSDME were optimized by using a Box-Behnken design, whereas the desorption solvent was optimized by using a Simplex-Centroid design. Under the optimized conditions, good analytical features were obtained, showing good linearity (at least up to 200 ng mL−1), enrichment factors from 18 to 26, method limits of detection in the low µg/g range (0.01–0.1 µg g−1), and good intra- and inter-day repeatability (relative standard deviations below 10 %). Matrix effects were negligible as long as no more than 0.1 and 0.25 g of fat- and water-soluble samples, respectively, were weighed and diluted to 25 mL. Finally, the proposed method was successfully applied to three commercial cosmetic samples of different formulation, and quantitative relative recovery values (76–108 %) were obtained by external calibration. This work expands the analytical potential of SBSDME to the use of new magnetic polymer-based sorbents. In addition, it contributes to the availability of methods to ensure the safety of cosmetic products through quality control by means of a green methodology.

Development of a low-alkalinity seawater sea sand concrete for enhanced compatibility with BFRP bar in the marine environment

To enhance the durability performance of Basalt Fiber Reinforced Polymer (BFRP) bar reinforced Seawater Sea Sand Concrete (SWSSC) structure components in the marine environment, this paper investigated the feasibility of reducing SWSSC alkalinity to improve its compatibility with BFRP bars. The low-alkalinity ternary mixtures were designed with ordinary Portland cement (OPC), silica fume (SF) and fly ash (FA) through the simplex centroid design method. The evolutions of micro-morphology and hydration phase were characterized by isothermal calorimeter, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD) and thermogravimetric analysis. The added SF and FA inhibit the formation of AFm phases and Friedel's salt, and consume the Portlandite content in seawater cement paste. Exposure in the marine environment can lead to magnesium and sulfur abundant zonation in the low-alkalinity SWSSC. The durability performances of BFRP bars reinforced SWSSC columns are evaluated through accelerated aging tests in a simulated marine environment at 55 °C. The tensile strength degradation of BFRP bars embedded in low-alkalinity SWSSC is significantly mitigated due to the less alkaline and less moist internal environment. After 180-day accelerated aging, the tensile strength retentions of BFRP bars wrapped by low-alkalinity and normal SWSSC are higher than 70% and less than 24%, respectively. After accelerated aging in seawater, the load-bearing capacity of BFRP bars reinforced low-alkalinity SWSSC column slightly improves and the ductility remains unaffected. Meanwhile, the ductility of BFRP bars reinforced normal SWSSC column is reduced by about 30% after conditioning. The research outcomes can serve as a solid base for the durability design of BFRP-SWSSC structures in the marine environment.

Combination of microwave-assisted extraction with dispersive micro solid-phase extraction as an efficient sample pretreatment method for the extraction of some antiparasitic drugs from cow liver, meat, and kidney samples.

A simple pretreatment method based on the combination of microwave-assisted extraction and dispersive micro solid phase extraction has been developed for the extraction of eprinomectin, doramectin, ivermectin, and abamectin from cow meat, liver, and kidney samples. The extracted drugs were determined using high-performance liquid chromatography equipped with a diode array detector. In this method, the solid samples were mixed with deionized water and organic solvent mixture, and the resulting mixtures were exposed to microwave irradiations to accelerate the analytes' extraction from the samples into the solution. Then, the supernatant was taken and mixed with a mixture of three sorbents optimized by a simplex centroid design. After vortexing and centrifuging, the sorbent particles were isolated and the adsorbed analytes onto the sorbent surface eluted with a natural deep eutectic solvent for more concentration. After centrifuging, the supernatant was taken and injected into the separation system. Acceptable repeatability (relative standard deviations ≤7.0%), high extraction recoveries (72%-86%) and enrichment factors (216-258), and low limits of detection and quantification (0.06-0.10 and 0.19-0.32ng/g, respectively) were acquired. The method was successfully applied for the assessment of the analytes in the mentioned samples and ivermectin was found in three samples.

Biotechnological valorization of oilseed cakes: Substrate optimization by simplex centroid mixture design and scale‐up to tray bioreactor

AbstractSunflower (SFC), rapeseed (RSC), and soybean cakes (SBC) are examples of oilseed cakes (OC) used in animal feed. Bioprocessing of these OC by solid‐state fermentation (SSF) aims to boost OC applications in feed and other industries by reducing antinutritional factors and releasing enzymes and antioxidants. A simplex centroid design was performed to optimize the substrate composition of SFC, RSC and SBC mixtures that maximize lignocellulolytic enzymes production by SSF with Aspergillus niger and consequently improve the nutritional properties of OC. Enzyme production by SSF of OC mixtures exceeded the activity values obtained using a single oilseed cake. A mixture composed of 50% (w/w) RSC and SBC was found to be the optimum substrate. The scale‐up from flasks to tray‐type bioreactors demonstrated SSF reproducibility, leading to the production of 299 U g−1 cellulase, 1476 U g−1 xylanase, 191 U g−1 β‐glucosidase and 220 U g−1 protease. The obtained enzymatic extract also presented antioxidant activity (around 50 μmol Trolox equivalents/g). This study demonstrated that bioprocessing of OC mixtures through SSF is an effective approach to obtain value‐added products with applications as feed or feed additives and to increase the liberation of bioactive compounds with applications in the feed, food, cosmetic and pharmaceutical industries. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.

Nutritional and Rheological Characterization of an Infant Flour Based on Parboiled Rice (Oryza sativa), Spirulina (Spirulina platensis), and Cashew Nut (Anacardium occidentale).

Protein-energy malnutrition and mineral deficiencies in children under five years are major problems in developing countries. The present study was thus carried out with the aim of proposing a weaning flour based on parboiled rice, spirulina, and cashew nut that meets the nutritional needs of children aged 06 to 24 months. To achieve this, the mixture design approach (a 9-point augmented simplex-centroid design) was used to obtain optimal blend of flour. The responses evaluated where proteins, lipids, carbohydrates, minerals (iron, calcium, phosphorus, potassium, sodium, magnesium, and zinc), carotenoids, fibers, and ash content. The rheological analyses (rapid viscosity analysis) were carried out on the optimal flour. It results that the optimal proportion of parboiled rice, spirulina, and cashew nut was, respectively, 85.80, 5.96, and 8.23. These conditions result in a protein, lipids, carbohydrates, carotenoids, ash, fibers, calcium, iron, magnesium, and zinc content of 14.15%, 9.04%, 68.46%, 8.2 mg, 3% ash, 4.98%, 510 mg, 16 mg, 65 mg, and 5 mg, respectively, and an energy value of 411.8 kcal. These optimate conditions resulted also in a peak viscosity of 60 cP and a final viscosity of 86 cP which are lower than the established value (1000 cP). Thus, the weaning flour based on parboiled rice, spirulina, and cashew nut obtained in these optimate conditions can meet the nutritional needs of children aged 06 to 24 months and is therefore an efficient weaning food to fight against child malnutrition.

Characteristics of biscuits containing different proportions of whole mung bean, wheat and rice brown flours.

A simplex-centroid design was used to evaluate the effect of proportions (0 to 100%) of whole wheat flour (WWF), whole mung bean flour (WMF) and whole rice flour (BRF) on the quality of cookies savory. The dough cut in the shape of a disks (37 mm × 2 mm) showed a 13% retraction in diameter when they contained exclusively WWF, it was less intense (5%) with BRF and null (0%) with WMF. The dough expansion occurred only vertically, the thicknesses of the WWF, WMF and BRF biscuits were 5.33, 2.79 and 2.13 times greater than the initial dough height, respectively. This characteristic showed high correlations with volumetric expansion (r = 0.95), specific volume (r = 0.90), hardness (r = 0.92), fracturability (r = 0.93) and spread factor (r = -0.96). BRF increased the value of the color difference of the biscuits up to 17.70, the effect of WMF was smaller (6.51). Only the radial expansion index correlated with the trough (r = 0.76), final viscosity (r = 0.79) and setback (r = 0.77) parameters. Considering the main desirable physical characteristics in savory biscuits, the highest global desirability obtained was for the proportion of 49% WWF, 24% WMF and 27% BRF.

Ultrasound–assisted solvent extraction combined with magnetic ionic liquid based-dispersive liquid–liquid microextraction for the extraction of mycotoxins from tea samples

In this work, for the first time, a combination of ultrasound–assisted mixed solvent extraction method with magnetic ionic liquid-based effervescent tablet–assisted dispersive liquid–liquid microextraction has been employed as an efficient method for the extraction of aflatoxins B1, B2, G1, and G2 and ochratoxin A from tea samples. In the extraction process, first the analytes were effectively extracted into a mixture of the solvents optimized by simplex centroid design with the aid of sonication process. Then, the extracted phase was used in the microextraction step to preconcentrate the analytes for obtaining high enrichment factors and low detection limits. Effervescent tablet eliminated the use of disperser solvent. Also magnetic ionic liquids usage as the extraction solvent directed the method towards a green approach. Various parameters that can affect the efficiency of the introduced method were evaluated and under the best experimental situations, satisfactory data including acceptable extraction recoveries (76–88%) and enrichment factors (304−352), low limits of detection (0.15–0.28 ng g–1) and quantification (0.49–0.92 ng g–1), and good repeatability (relative standard deviations equal to or less than 3.1% and 3.5% for intra– and inter-day precisions, respectively) were obtained. Lastly, the proposed method was utilized for the determination of the studied mycotoxins in different tea samples sold in Tabriz city (Iran).

Bacterial Cellulose/Tomato Puree Edible Films as Moisture Barrier Structures in Multicomponent Foods.

Edible films have been studied mainly as primary packaging materials, but they may be used as barrier layers between food components, e.g., by reducing the moisture migration between components with contrasting water activities. Since edible films are part of the food itself, components adding sensory appeal (e.g., fruit purees) are usually desirable. The objective of this study was to develop a film to be applied as a moisture barrier between nachos and guacamole. Ten film formulations were prepared according to a simplex centroid design with three components—a polysaccharide matrix (consisting of a 5:1 mixture of bacterial cellulose—BC—and carboxymethyl cellulose), tomato puree (for sensory appeal), and palm olein (to reduce hydrophilicity)—and produced by bench casting. The film with the highest palm olein content (20%) presented the lowest water vapor permeability, and its formulation was used to produce a film by continuous casting. The film was applied as a layer between nachos and guacamole, and presented to 80 panelists. The film-containing snack was preferred and considered as crispier when compared to the snack without the film, suggesting that the film was effective in reducing the moisture migration from the moist guacamole to the crispy nachos.

Simplex centroid mixture design, DI-ESI-MS, and chemometric analysis-guided isolation of parinarioidin C from bark of Brosimum parinarioides (Moraceae)

Brosimum parinarioides , a plant species native to the Amazonian region, is used in folk medicine for the treatment of several diseases. However, knowledge regarding its phytochemical content is scarce. In order to investigate the phytochemical composition of B. parinarioides , an integrative approach based on simplex-centroid design, direct infusion electrospray ionization mass spectrometry (DI-ESI-MS), and chemometric analysis was adopted. According to simplex-centroid design, dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol-based (EtOH) extracts were prepared and analyzed using DI-ESI-MS, and their chemical profile was submitted to principal component analysis (PCA) and hierarchical cluster analysis (HCA). The AcOEt extract from the bark was obtained on a large scale and subjected to chromatographic separation. The multivariate analysis indicated the formation of three groups and highlighted isoliquiritigenin ( 1 ), licoagrochalcone A ( 2 ), caffeic acid glucoside ( 3 ), epicatechin-glycoside ( 4) , caffeic acid ( 5 ), and one unknown compound, as being responsible for the segregation of these groups. Thus, the new compound was isolated and characterized using 1D and 2D nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry (HR-MS) as parinarioidin C ( 10 ). In addition, parinarioidin A ( 6 ), parinarioidin B ( 7 ), 3- O -caffeoylquinic acid ( 8 ), and kanzonol C ( 9 ) were tentatively identified based on manual interpretation of MS/MS spectra. Overall, the integrative approach proposed in the study provided a simple and effective model to dereplicate known compounds and guide the isolation of a new compound from a native amazon species, thus improving the knowledge regarding the phytochemical content of B. parinarioides . • One new compound was isolated from Brosimum parinarioides. • Nine phenolic compounds were identified based on the MS/MS data. • This study provided an effective model to guide the isolation of new natural products.

Multi-response optimization of extraction yield, total phenols-flavonoids contents, and antioxidant activity of extracts from moroccan Lavandula stoechas leaves: Predictive modeling using simplex-centroid design

This study aimed to improve the extractive effect of four solvents and their combinations on phenolic compounds from Moroccan Lavandula stoechas leaves. A simplex-centroid design was used in a solvent system containing ethyl acetate, methanol, ethanol, acetone, and their mixtures to optimize the five responses: extraction yield, total phenol content (TPC), total flavonoids content (TFC), and antioxidant activity by DPPH and FRAP assays. HPLC-DAD then analyzed the obtained extracts from each pure solvent. Sinapic acid, epicatechin, and rosmarinic acid were identified as major compounds. After optimizing each response separately according to the validated special cubic models, the desirability function has allowed the optimization of all responses simultaneously. The optimal solvent system was the ternary mixture (50:36:14 v/v/v) methanol: ethanol: acetone, while the optimal values were 14.63%, 292.23 mg GAE/g DE, 95.73 mg QE/g DE, 27.55 μg/mL and 3.13 μg/mL for yield, TPC, TFC, DPPHIC50, and FRAPEC50, respectively. This study shows that the combination of the solvent mixture may be applicable to giving better antioxidant activities than those given by some commercial antioxidants and may subsequently be useful as natural food preservatives.

Optimization Extraction for Total Phenolic, Flavonoid Contents, and Antioxidant Activity with Different Solvents and UPLC-MS/MS Metabolite Profiling of Justicia gendarussa Burm.f

Abstract Justicia gendarussa Burm.f contains polyphenol, which has pharmacological activity. Therefore, this study aims to show the potential of antioxidant compounds in J. gendarussa. The extraction method used was an experimental design that maximized phenolic recovery with the highest antioxidant activity from the leaves of this plant. Furthermore, a simplex-centroid design was used to evaluate the various extractor solvents (water, ethanol, and hexane) and their binary or ternary mixtures, while UPLC-MS/MS analysis was used to identify bioactive compounds. The total phenol (TPC) and flavonoid content (TFC) of the optimized extracts were determined using Follin-Ciocalteu and colorimetric methods, as well as their antioxidant activity were determined using the 2,2-diphenyl-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The results was optimized to a value of 0.844 using water-hexane solvents with a predicted TPC, TFC, DPPH, and FRAP of 112.076 mg GAE/g, 34.926 mg QE/g, 45.477 µmol TE/g, and 353.611 µmol TE/g, respectively. Additionally, the UPLC-MS/MS analysis showed 62 compounds such as phenolics, isoflavonoids, alkaloids, terpenoids, alcohols, and other groups of components. This study shows the potential of antioxidant compounds J. gendarussa. Keywords: Extraction optimization, Justicia gendarussa Burm.f, Simplex centroid design, Polyphenols, Antioxidant

Formulation and Optimization of Gastro retentive Glimepiride Floating Matrix Tablets

The main objective of this research investigational studies is to formulate floating matrix tablets of glimipride by applying simplex centroid design for optimization technique and by direct compression method. The simplex Centroid configuration was drilled as an enhancement strategy by adjusting the amount of three components all the while and holding back their total concentration constant. Ingredients HPMC K15m, Kappa-carrageenan and sodium bicarbonate as X1,X2,X3 independent Variables while response variables Y1 floating lag time Y1, Percentage drug released after 1 hour Y2% and t90 time required for 90% were considered as response variable factors for formulation and optimization of total 14 formulations simplex centroid design was applied. The measures of HPMC K15M (X1), kappa-Carrageenan (X2) and sodium bicarbonate (X3) were utilized as the autonomous factors while coasting slack time (Y1), Percentage drug discharged after 1 hour(Y2) and time required for 90% (t90) were taken as the reaction factors. According to the simplex centroid configuration complete 14 formulations were formulated. Matrices were evaluated for physical parameters, in-vitro buoyancy, swelling ability and adhesion retention period. It was inferred that the blend of kappa carrageenan and HPMC K 15 M builds the adaptability in the release pattern of the drug. This examination sets up the utilization of simplex centroid structure in the advancement of coasting network tablets with least experimentation.

Methylphenidate Fast Dissolving Films: Development, Optimization Using Simplex Centroid Design and In Vitro Characterization.

The focus of this study was to design and optimize methylphenidate hydrochloride mouth dissolving film (MDF) that can be beneficial in an acute condition of attention deficit hyperactivity disorder (ADHD) and narcolepsy. Solvent casting method was used for the preparation of this film. Optimization of the effect of independent variables such as the number of polymers and active pharmaceutical ingredients [hydroxypropyl methyl cellulose (HPMC) E5, HPMC E15, and maltodextrin], % of drug release, disintegration time, and tensile strength of the film done using simplex centroid design. Complex formation of the film was tested using fourier-transform infrared spectroscopy and differential scanning calorimetry study. The multiple regression analysis was obtained from equations of the results that adequately describe influence of the independent variables on the selected responses. Polynomial regression analysis, contour plots, and 3-D surface plots were used to relate dependent and independent variables. Experimental results indicated that different polymer amounts had complex effects on % drug release from the film, disintegration time as well as the tensile strength of the film. The observed responses were in near alignment with expected values calculated from the developed regression equations as shown by percentage relative error. Final formulation showed more than 95% drug release within 2 min and was shown to disintegrate within a minute that had good tensile strength. These findings suggest that MDF containing methylphenidate hydrochloride is likely to become a choice of methylphenidate hydrochloride preparations for treatment in ADHD and narcolepsy conditions.

Reformulating Bread Using Sprouted Pseudo-cereal Grains to Enhance Its Nutritional Value and Sensorial Attributes.

Sprouting is an effective treatment for improving nutritional and bioactive properties as well as lowering the anti-nutritional compounds in pseudo-cereals. Enhancing nutritional properties when using sprouted pseudo-cereals flours as a baking ingredient requires tailored formulation. Simplex centroid designs and response surface methodology has been applied in the present study to define the ideal proportions of ternary blends of sprouted kiwicha (SKF), cañihua (SCF) and wheat flours (WF) to simultaneously enhance the content in bioactive compounds (γ-aminobutyric acid, GABA, total soluble phenolic compounds and TSPC), as well as sensory (odor, color, taste and texture) and functional attributes (antioxidant activity, AA) while reducing phytic acid (PA) content of bread. The effect of gastric and intestinal digestion on bioactive compounds, AA, PA and starch hydrolysis was also evaluated. Mixture design allowed for the identification of optimal formulation (5% SKF, 23.1% SCF, 71.9% WF) that can be used to obtain breads with higher content of GABA, TSPC, AA, overall sensorial acceptability (scores > 7) and reduced PA content and glycemic index. Moreover, this study demonstrated that these nutritional and health benefits provided by the replacement of WF by sprouted pseudo-cereal flours remained upon digestion. The results of this study indicated that WF replacement with SKF and SCF is sensory acceptable and improved the nutritional quality of bread.

A mixed deep eutectic solvents-based air-assisted liquid–liquid microextraction of surfactants from exhaled breath condensate samples prior to HPLC-MS/MS analysis

A ternary solvent system-based air-assisted liquid–liquid microextraction procedure was developed for the extraction of three surfactants from exhaled breath condensate samples prior to their determination by high performance liquid chromatography-tandem mass spectrometry. In this approach, different deep eutectic solvents were synthesized based on phosphocholine chloride and fatty acids and their mixtures were used as the extraction solvents to effective extraction of the analytes. To obtain the optimum composition of the extraction solvents, a simplex centroid design approach was used. Then the effective parameters were studied by response surface methodology using central composite design. The obtained data after optimization showed that 6 times was the best extraction time for the developed procedure. When the sample solution pH was adjusted at 3.7, the method reached to higher extraction efficiency which can be related to the fact that the analytes were in the protonated forms. Increasing the sample solution temperature up to 50 °C enhanced the migration rate of the analytes into the extraction solvent and the method efficacy was increased. Also addition of sodium chloride at 2.8% (w/v) had a positive effect on the method efficiency which can be related to decreasing the analytes solubility in the sample solution. Under optimal conditions, the method showed satisfactory coefficient of determination (≥0.9979), low limit of detection (0.12–0.23 ng mL−1) and quantification (0.39–0.76 ng mL−1), acceptable repeatability in deionized water (relative standard deviation ≤ 8.2%) and in exhaled breath condensate (relative standard deviation ≤ 7.2%), and acceptable extraction recovery (75–86%) and enrichment factor (71–86). Considering these results, the developed method provided a quick and efficient way to determine surfactants in the exhaled breath condensate collected from expiratory circuit of the mechanical ventilator. It can be used in drug monitoring and clinical studies.

Application of the Simplex-Centroid Mixture Design to Biomass Charcoal Powder Formulation Ratio for Biomass Charcoal Briquettes

This study aims to increase the quality and value of raw materials with a low higher heating value, HHV (secondary ingredients), but which is abundantly available throughout the year by mixing it with high HHV materials (main ingredients) to obtain quality and standardized charcoal products in accordance with the industrial product standards as approved for commercial use. As for the ingredients, charcoal A is Eucalyptus bark coal (EuBC) with an average HHV of 3779.98 cal/g, charcoal B is rice husk coal (RHC) with an average HHV of 4863.29 cal/g, and charcoal C is charcoal from a biomass power plant (CBPP) with an average HHV of 5991.18 cal/g. The results from the simplex-centroid mixture design method allowed increased quality and value of the biomass charcoal powder (raw material) that has a low heating value but is sufficiently available throughout the year due to the mixing of secondary ingredients with raw materials that have a high heating value (main ingredient). The charcoal briquettes production must be qualified and meet the industrial product standards, and be approved for commercial use.

Production of bio‐fertilizer by biotransformation of poultry waste enriched with molasses and algae

AbstractThis research work consists on valorizing poultry waste by biotransformation into biofertilizers, associating this agro‐industrial waste with algae (abundant natural resources) and molasses (a by‐product of the sugar refining industry) ensuring a good contribution of nutritional chemical elements and obtaining a balanced formulation. A total of seven different formulations of the above three components, were examined in a simplex centroid design. A fungal inoculum of Aspergillus niger was used as a fermentation agent for better quality of biotransformation. The monitoring of this biotransformation is ensured during 15 days by following the evolution of physicochemical and microbiological parameters and, to understand the bioconversion of the simple compounds of the biofertilizer mixture such as short aliphatic chains, sugar, and amino acids into soluble mineral compounds, a Fourier transform infrared spectroscopy (FTIR) analysis was carried out before and after biotransformation. Finally, germination and fertilization tests were performed to evaluate the efficiency of the final product on a barley crop. The overall results of the present study showed that the mixture which contained 68.75% poultry waste, 12.5% molasses, and 18.75% algae presented the better microbiological and chemical safety criteria required for a good biofertilizer according to NF U44‐551 standard.