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Methanol steam reforming (MSR) is considered as an effective way to provide on‐board hydrogen production technology for fuel cell applications. CuFe1.2Al.8O4 spinel catalyst was synthesized by sol–gel method and the chemical and physical properties were studied in‐depth. X‐ray diffraction, hydrogen‐temperature programmed reduction (H2‐TPR), BET, and scanning electron microscopy were used to characterize the catalysts with reaction times of 20, 50, and 100 h. The results of H2‐TPR showed that 90% of spinel Cu2+ was released after 100 h reaction. BET results show that the specific surface area and pore characteristics of the catalyst have not changed greatly after reaction for 20, 50, and 100 h. Furthermore, in the unsteady‐state test, CuFe1.2Al.8O4 exhibited excellent catalytic activity and thermal stability under long‐term repeated start‐up and stop cycles. At 275°C, the methanol conversion rate remained around 94% and the CO selectivity remained below 1%. Therefore, the catalyst synthesized in this study has excellent stability and low CO selectivity, making it a highly promising on‐board hydrogen production catalyst in the field of HT‐proton exchange membrane fuel cells (PEMFCs). [ABSTRACT FROM AUTHOR]

Abstract Dimensionally stable anodes of titanium (Ti) metal coated with mixed metal oxides (MMO) are widely used in several electrochemical applications, especially chloro-alkali electrolysis. Herein, we deposited MMO coatings on Ti substrates in different compositions, namely, (60%RuO2-40%TiO2), (60%RuO2-30%TiO2-10%IrO2), and (60%RuO2-20%TiO2-15%IrO2-5%Ta2O5), where RuO2 has the same percentage ratio in all coatings. The aim was to use these electrodes for chlorine evolution reaction (CER) and oxygen evolution reaction (OER) applications. Electrochemical characterization of the coated samples was performed to identify the best Ti/MMO electrodes with the highest efficiencies among the various prepared combinations. The role of IrO2 and Ta2O5 in enhancing corrosion resistance and electrochemical efficacy was up for debate. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses were exploited to determine the surface morphology, chemical composition, crystallinity, surface composition, and chemical states of the acquired coatings. The differential scanning calorimetry (DSC) method was used to evaluate the apparent activation energy ( $${{\text{E}}}_{{\text{a}}}$$ E a ) of the deposited MMO. Additionally, the electrochemical performance of our designed coatings was scrutinized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), a current on–off test, a CV stability test (ST), and an accelerated stability test (AST). Furthermore, linear sweep voltammetry (LSV) was incorporated to assess the catalytic efficacy of the prepared anodes toward the CER in a brine solution of pH 2 and the OER in 1 M H2SO4. It became clear that the CER and OER incurred almost the same potential value (1.1 V) on both Ti/RuO2-TiO2 and Ti/RuO2-TiO2-IrO2 electrodes. However, on the Ti/RuO2-TiO2-IrO2-Ta2O5 anode, there was a 0.2 V potential difference between the CER occurring at 1.1 V and the OER happening at 1.3 V.

Dimensionally stable anodes of titanium (Ti) metal coated with mixed metal oxides (MMO) are widely used in several electrochemical applications, especially chloro-alkali electrolysis. Herein, we deposited MMO coatings on Ti substrates in different compositions, namely, (60%RuO2-40%TiO2), (60%RuO2-30%TiO2-10%IrO2), and (60%RuO2-20%TiO2-15%IrO2-5%Ta2O5), where RuO2 has the same percentage ratio in all coatings. The aim was to use these electrodes for chlorine evolution reaction (CER) and oxygen evolution reaction (OER) applications. Electrochemical characterization of the coated samples was performed to identify the best Ti/MMO electrodes with the highest efficiencies among the various prepared combinations. The role of IrO2 and Ta2O5 in enhancing corrosion resistance and electrochemical efficacy was up for debate. Scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses were exploited to determine the surface morphology, chemical composition, crystallinity, surface composition, and chemical states of the acquired coatings. The differential scanning calorimetry (DSC) method was used to evaluate the apparent activation energy ( E a ) of the deposited MMO. Additionally, the electrochemical performance of our designed coatings was scrutinized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), a current on–off test, a CV stability test (ST), and an accelerated stability test (AST). Furthermore, linear sweep voltammetry (LSV) was incorporated to assess the catalytic efficacy of the prepared anodes toward the CER in a brine solution of pH 2 and the OER in 1 M H2SO4. It became clear that the CER and OER incurred almost the same potential value (1.1 V) on both Ti/RuO2-TiO2 and Ti/RuO2-TiO2-IrO2 electrodes. However, on the Ti/RuO2-TiO2-IrO2-Ta2O5 anode, there was a 0.2 V potential difference between the CER occurring at 1.1 V and the OER happening at 1.3 V. [ABSTRACT FROM AUTHOR]

Context: Well-organised leaf architecture produces compact canopies and allows for greater sunlight penetration, higher photosynthetic rates, and thus greater yields. Breeding for enhanced leaf architecture of sorghum (Sorghum bicolor L.), a key food source in semi-arid regions, benefits its overall production. Aims: The study focuses on selecting useful genotypes with excellent leaf architecture for grain sorghum improvement. Methods: In total, 185 sorghum genotypes were subjected to multi-environment trials. Leaf flagging-point length, leaf length, leaf width, leaf angle and leaf orientation value (LOV) were characterised under field conditions. Genotype + genotype × environment interaction (GGE) biplot analysis was used to identify the most stable genotypes with the highest LOV. Key results: Statistical analysis showed significant effects of genotype × environment interaction (P < 0.001), and high broad-sense heritability for the traits. Correlation analysis demonstrated negative correlations (P < 0.001) between LOV and its components. Singular value decomposition of LOVs in the first two principal components explained 89.19% of the total variation. GGE biplot analysis identified G55 as the ideotype with the highest and most stable LOV. Conclusions: Leaf architecture optimisation should be given greater attention. This study has identified a genotype with optimal and stable leaf architecture, laying the foundation for improvement in breeding to increase overall yields of sorghum. Implications: Genotype G55 can be utilised as a parent with other parents that display economically important characteristics in breeding programs to produce offspring that can be planted densely to increase population yields. Genotypes identified with loose leaf architecture are useful in dissecting genes controlling leaf architecture by crossing with G55 to construct genetic mapping populations. Grain sorghum is a food source for people in semi-arid regions; however, its productivity is compromised by its inefficient leaf architecture. Aiming to improve sorghum productivity, the research focused on evaluation of leaf architectural traits and identification of ideotypes with outstanding leaf architecture. Through multi-environment trials, an ideal genotype was selected for best leaf architecture performance, which will be useful as the parental line to optimise sorghum leaf architecture in a breeding program. [ABSTRACT FROM AUTHOR]

Pump-turbines experience complex flow phenomena and fluid–structure interactions during transient operations, which can significantly impact their stability and performance. This paper presents a comprehensive field test study of the pump mode startup process for a 150 MW prototype pump-turbine. By analyzing pressure fluctuations, structural vibrations, and their short-time Fourier transform (STFT) results, multiple stages were identified, each exhibiting distinct characteristics. These characteristics were influenced by factors such as runner rotation, free surface sloshing in the draft tube, and rotor–stator interactions. The natural frequencies of the metallic components varied during the speed-up and water-filling stages, potentially due to gyroscopic effects or stress-stiffening phenomena. The opening of the guide vanes and dewatering valve inside the guide vanes significantly altered the amplitude of the rotor–stator interaction frequency, transitioning the vibration behavior from forced to self-excited regimes. Interestingly, the draft tube pressure fluctuations exhibited sloshing frequencies that deviated from existing prediction methods. The substantial phenomena observed in this study can help researchers in the field to deepen the understanding of the complex behavior of pump-turbines during transient operations and identify more meaningful research directions. [ABSTRACT FROM AUTHOR]

Copyright of China Fiber Inspection is the property of China Fiber Inspection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stabilisers are an integral part of a propellant composition. They are essential for ensuring the chemical stability of nitrate‐ester based propellants, preventing oxidation, chain scission and uncontrolled heat generation. Progress is being made, especially in Europe, with REACh legislation (1907/2006) to use more environmentally‐friendly compounds. New stabilisers with a greener environmental profile and producing less toxic daughter products have been investigated by several groups, and several compounds demonstrated even better performances – more chemical stability and therefore longer shelf lives than formulations with the currently‐used stabilisers. Additionally, the good efficiencies and lower toxicities of the daughter products of the "green" stabilisers are also evaluated. This paper is a continuation of our previous work and demonstrates that for industrially‐manufactured propellants, that the tests performed by four different entities validate the stability and compatibility of the propellants, investigated previously on a laboratory scale, providing the community with safer formulations for the environment and health. [ABSTRACT FROM AUTHOR]

In the present, whitening products are most popular in the cosmetics market, and nanoemulsions are effective drug delivery systems through the skin. The objective of this study was to investigate multiple nanoemulsion formulations for lightning skin effects. The method of this study was the selection of active compounds based on synergistic tyrosinase inhibition activity, formulation preparation by low and high energy methods, physicochemical property determination, stability test, cell toxicity, and anti-melanogenesis in cell culture. From the results, it was found that tyrosinase inhibition with substrate l-tyrosine from the mixture of curcumin and alpha-arbutin gave the highest activity with an IC50 of 63.58 ± 4.99 μM, showed a synergistic effect at a CI value of 0.99, and selected these compounds to develop formulations by the low energy method. However, the most formulations prepared by this method were unstable and phase separated, while the high energy method gave the most formulations with good properties, which were selected for further investigation. The best formulation was 2DS which showed internal droplet morphology in the range of nanometers under a TEM microscope. For 3 months stability test, the formulations had no phase separation and gave the slightly changed values of particle size, polydispersity index (PDI), zeta potentials, and pH values. In addition, multiple nanoemulsions also enhanced the stability of active compounds, with the highest percentage of remaining content of curcumin and arbutin at 94.69 and 90.45 %, respectively at 4 °C for 3 months. In a cell culture test on B16F10, 2DS at 0.05 g/ml gave no cell cytotoxicity and anti-melanogenesis at 57.75 ± 5.74 %, the same potency as kojic acid at a concentration of 20 μg/ml. Therefore, this study will be useful to prepare multiple nanoemulsions for further development into novel health care products.

During the flood season, Francis turbines often operate under low-head and full-load conditions, frequently experiencing significant pressure pulsations, posing potential threats to the safe and stable operation of the units. However, the factors contributing to substantial pressure pulsations in Francis turbines are multifaceted. This paper focuses on a mixed-flow hydroelectric generating unit at a specific hydropower station. Field tests were conducted to investigate abnormal vibrations and hydraulic pressure pulsations under low-head and full-load conditions. Utilizing the Navier–Stokes equations and the RNG k-ε turbulence model, the unsteady flow field within the turbine under these conditions was calculated. The results indicate that the abnormal pressure pulsations detected in the bladeless zone between the wicket gates and the turbine inlet are due to operational points deviating from the normal operating range of the turbine. When water flows at a large inflow angle, striking the turbine blade heads, it leads to significant flow separation and vortex formation at the back of the blade inlet edges, causing severe vibrations in the hydroelectric generating unit. These findings provide a basis and assurance for the safe and stable operation of the power station. [ABSTRACT FROM AUTHOR]

Copyright of China Surfactant Detergent & Cosmetics (2097-2806) is the property of China Surfactant Detergent & Cosmetics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on the current situation of student cultivation mode and student management in colleges and universities, this paper puts forward six basic assumptions on student cultivation and management, and combines the assumptions to obtain the game payment matrix of student cultivation mode and student management. The dynamic equations of the cultivation and management process are reproduced by using mathematical calculus to derive the game payment matrix. Under the constraints, the game evolution model equilibrium point is tested for stability, the game evolution state is derived, and the game evolution model is completed to optimize the innovation of college student training mode and student management mechanism. Numerical simulation analysis is performed on the evolutionary game of college student cultivation and management based on the parameter settings of the evolutionary game model. The results show that the evolutionary game model will converge to a stable strategy point when the ratio of managers (teachers) and students’ initial participation in cultivation and management activities is set to (0.05, 0.95), (0.05, 0.05), (0.95, 0.05) or (0.95, 0.95). This study has a beneficial impact on cultivating exceptional talents, and it also provides a solid resource for society to deliver top-notch talent.

Abstract Objective Despite the studies that have investigated the reliability of Upper Extremity Functional Tests(UEFTs), the reliability of Closed Kinetic Chain Upper Extremity Stability(CKCUES), Seated Medicine Ball Throw(SMBT), push-up(PU) and Unilateral Seated Shot Put(USSP) tests in overhead athletes has yet to be assessed. The objective of this study was to determine both the relative and absolute test–retest reliability of the four UEFTs in female overhead athletes. Methods Twenty-nine female overhead athletes (age: 26.6 ± 5.29 years) underwent the four UEFTs twice within a three- day interval. The upper limb stability was assessed through PU and CKCUES tests, while the power was assessed though SMBT and USSP tests. The Intraclass Correlation of Coefficient (ICC) was applied to assess the relative reliability. Absolute reliability was determined by calculating the Standard Error of Measurement (SEM) and the Minimal Detectable Change (MDC). Furthermore, Bland–Altman plots were used to detect the agreements between the two measurements. Results The relative reliability of PU, CKCUES, SMBT, and non-dominant arm USSP tests was excellent (ICC = 0.83, 0.80, 0.91, and 0.83, respectively). SEM was within a range of 1.69 to 1.72 for stability tests and a range of 13.61 to 52.12 for power (based on a 95% confidence interval). The MDC was 4.68 for PU and 4.75 for CKCUES test. At least four repetitions are needed to be considered a real improvement on PU and CKCUES tests. This value was 144.04, in SMBT and 59.03, 37.62 cm (dominant and non-dominant arm, respectively) in USSP tests, which represents the minimum change that must occur to be considered an athlete’s progression. Conclusion This study revealed that both the upper limb stability and power tests have acceptable relative and absolute intra-rater reliability in female overhead athletes. These can be considered as reliable tools in research and clinical settings.

Caprine milk is a nutraceutical source with various benefits for human health. The content of bioactive peptides in caprine milk has biological functions as an antioxidant, anti-inflammatory, and antimicrobial. Based on the benefits of caprine and its dairy products, we utilized them as the main ingredient for soap formulation. Stability evaluation is important to determine the shelf life and safety of the soap. This study aimed to examine the effect of different temperatures and storage time on the physical characteristic, pH level, heavy metal contents, and the antimicrobial activity of the soaps. We showed that the color and aroma of the soaps were relatively stable with a minor change in their hardness levels. The level of pH for all samples was around 7,00–8,70, which could be safely used on human skin. The level of heavy metal including Cd, Pb, and Hg were below the maximum standard allowed for the soap products. A little increase in the number of bacteria colonies were found when the soaps were stored at the longer durations. Based on the physical stability, pH level, heavy metal contents, and antimicrobial activity, these soaps might be safe for application on human skin.

Objective: Despite the studies that have investigated the reliability of Upper Extremity Functional Tests(UEFTs), the reliability of Closed Kinetic Chain Upper Extremity Stability(CKCUES), Seated Medicine Ball Throw(SMBT), push-up(PU) and Unilateral Seated Shot Put(USSP) tests in overhead athletes has yet to be assessed. The objective of this study was to determine both the relative and absolute test–retest reliability of the four UEFTs in female overhead athletes. Methods: Twenty-nine female overhead athletes (age: 26.6 ± 5.29 years) underwent the four UEFTs twice within a three- day interval. The upper limb stability was assessed through PU and CKCUES tests, while the power was assessed though SMBT and USSP tests. The Intraclass Correlation of Coefficient (ICC) was applied to assess the relative reliability. Absolute reliability was determined by calculating the Standard Error of Measurement (SEM) and the Minimal Detectable Change (MDC). Furthermore, Bland–Altman plots were used to detect the agreements between the two measurements. Results: The relative reliability of PU, CKCUES, SMBT, and non-dominant arm USSP tests was excellent (ICC = 0.83, 0.80, 0.91, and 0.83, respectively). SEM was within a range of 1.69 to 1.72 for stability tests and a range of 13.61 to 52.12 for power (based on a 95% confidence interval). The MDC was 4.68 for PU and 4.75 for CKCUES test. At least four repetitions are needed to be considered a real improvement on PU and CKCUES tests. This value was 144.04, in SMBT and 59.03, 37.62 cm (dominant and non-dominant arm, respectively) in USSP tests, which represents the minimum change that must occur to be considered an athlete's progression. Conclusion: This study revealed that both the upper limb stability and power tests have acceptable relative and absolute intra-rater reliability in female overhead athletes. These can be considered as reliable tools in research and clinical settings. [ABSTRACT FROM AUTHOR]

Pulmonary drug transport has numerous benefits. Large surface areas for absorption and limited drug degradation of the gastrointestinal system are provided through the respiratory tract. The administration is painless and easy for the patient. Due to their better stability when compared to liquid formulations, powders have gained popularity among pulmonary formulations. In the pharmaceutical sector, quality assurance and product stability have drawn a lot of attention. Due to this, it was decided to perform a long-term stability study on a previously developed, nanosized dry powder inhaler (DPI) formulation that contained meloxicam. Wet milling was implemented to reduce the particle size, and nano spray-drying was used to produce the extra-fine inhalable particles. The particle diameter was determined using dynamic light scattering and laser diffraction. Scanning electron microscopy was utilized to describe the morphology. X-ray powder diffraction and differential scanning calorimetry were applied to determine the crystallinity. In an artificial lung medium, the in vitro dissolution was studied. The Andersen Cascade Impactor was used to investigate the in vitro aerodynamic characteristics. The stability test results demonstrated that the DPI formulation maintained its essential qualities after 6 and 12 months of storage. Consequently, the product might be promising for further studies and development. [ABSTRACT FROM AUTHOR]

Copyright of Electric Machines & Control / Dianji Yu Kongzhi Xuebao is the property of Electric Machines & Control and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the flood season, Francis turbines often operate under low-head and full-load conditions, frequently experiencing significant pressure pulsations, posing potential threats to the safe and stable operation of the units. However, the factors contributing to substantial pressure pulsations in Francis turbines are multifaceted. This paper focuses on a mixed-flow hydroelectric generating unit at a specific hydropower station. Field tests were conducted to investigate abnormal vibrations and hydraulic pressure pulsations under low-head and full-load conditions. Utilizing the Navier–Stokes equations and the RNG k-ε turbulence model, the unsteady flow field within the turbine under these conditions was calculated. The results indicate that the abnormal pressure pulsations detected in the bladeless zone between the wicket gates and the turbine inlet are due to operational points deviating from the normal operating range of the turbine. When water flows at a large inflow angle, striking the turbine blade heads, it leads to significant flow separation and vortex formation at the back of the blade inlet edges, causing severe vibrations in the hydroelectric generating unit. These findings provide a basis and assurance for the safe and stable operation of the power station.

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aims: Chemical mouthwash has been used for ages as one of the oral hygiene practices, but due to its side effects, mouthwash formulated from plants has become a better alternative. Andrographis paniculata (AP) is an herb plant known for its antibacterial effects. Thus, this study was aimed to compare the antibacterial activity of AP with commercial mouthwash and to observe the stability of mouthwash formulated from AP. Methodology and results: Aqueous extract of AP was used to prepare herbal mouthwash. The antibacterial activity of AP mouthwash and three commercial types of mouthwash, namely Colgate Plax, Oral B and Listerine, were determined by minimum inhibitory concentration (MIC) through broth dilution method and minimum bactericidal concentration (MBC) against selected oral pathogens; Staphylococcus aureus, Streptococcus mutans and Streptococcus sobrinus. The AP mouthwash was stored for six months and a year at three different storages to assess its stability and microbial contamination by the pour and drop plate method. The results indicated that Colgate Plax and AP mouthwash have the best antibacterial activity compared to two other commercial types of mouthwash with an inhibition percentage of 95.96% at 15.63 mg/mL for S. aureus (Colgate Plax) and 168.45% at 62.5 mg/mL for S. aureus, 93.75% at 7.81 mg/mL for S. mutans and 98.51% at 7.81 mg/mL for S. sobrinus (AP mouthwash). The parameters measured remained unchanged during storage except at room temperature, while the pH level ranged from 6.72 to 7.45. The AP mouthwash showed stable sterility throughout the study. Conclusion, significance and impact of study: The AP mouthwash shows good antibacterial activity against oral pathogens and is almost similar to other commercial mouthwashes and stable to be used for up to a year. In addition, it has excellent potential as an alternative herbal mouthwash in treating oral pathogens effectively. [ABSTRACT FROM AUTHOR]

The virtual synchronous generator (VSG) control is a promising solution for the grid-forming converters to enhance the inertia of the converter-based power grid. The virtual inertia and output impedance of the VSG are the important behaviors to be focused. However, the virtual inertia of grid-forming converters may cause active power oscillation due to the interaction with the power inertia of grid through the low-frequency band grid impedance. Besides, the resonance can be also triggered by the interaction between middle-frequency impedance of power grid and output impedance of converter. In order to test the stability of grid-forming converter, accurate emulation of grid behaviors from more aspects, including inertia and impedance under wider frequency ranges, is becoming critical. This article proposes a grid emulation method to mimic the inertia and impedance characteristics of power grid, targeting for the stability test of grid-forming converter under multifrequency bands. A high-switching-frequency converter and a low-switching-frequency converter are adopted in the proposed emulator structure to achieve both high capability in respect to control bandwidth and power level. Moreover, the virtual impedance control is integrated with the VSG control to emulate the line impedance and inertia within relatively wider frequency ranges. The realization of virtual impedance is achieved without derivation terms nor low pass filter. Finally, the performance of the proposed emulator is verified by various simulations and experimental measurements. [ABSTRACT FROM AUTHOR]

Plantago major of the plantain family has been observed as a wound-healing plant species on account of its ursolic acid (UA) content. The study's objectives were twofold: to prepare UA gels from P. major and validate the analytical method using TLC-densitometer. Here, vacuum and open column chromatography were used to isolate UA from the methanol extract of P. major. Afterward, data on the compound's physical properties and infrared (IR) spectroscopy, electrospray ionization mass spectrometry (ESI-MS), and Nuclear Magnetic Resonance (1H NMR, 13C NMR) results were analyzed. Carbomer and hydroxy propyl methyl cellulose (HPMC) were used as gelling agents to make the UA gel. To validate the analytical method, TLC-densitometer was performed using TLC silica gel 60 F254 plates (the stationary phase) and a mixture of toluene: ethyl acetate: formic acid (8:2:0.1, the developing solvent). The results showed that the UA gel was successfully prepared using both gelling agents and that its physical properties (i.e., visual forms, viscosity, and flow behavior) and pH values were maintained throughout the 90-day accelerated stability test (40±2°C; 75±5% RH). In addition, the method validation results indicated compliance with relevant parameters: linearity (r=0.998), limit of detection (4.55 ng/spot) and limit of quantification (15.17 ng/spot), recovery (95.04-116.82%), intraday precision (RSD=1.24-1.96%) and interday precision (RSD=6.29%). Overall, the UA gel is stable for 90 days (accelerated stability test), and the TLC-densitometry proposed in the research can be used to identify and measure the chemical content of a gel preparation. [ABSTRACT FROM AUTHOR]

Abstract Natural products are considered an important source of the therapeutic arsenal currently available. Among these alternatives are the seeds of Ambrosia peruviana (altamisa), whose extract has shown an anti-inflammatory effect. The main objective of this work was to perform a preformulation study of Ambrosia peruviana seeds ethanolic extract, where the main factors that affect the physical, chemical, and pharmacological stability of the extract were evaluated, as well as a compatibility study by differential scanning calorimetry (DSC) analysis against different excipients. A dry extract was obtained by rotary evaporation of the seeds macerated with 96% ethanol. The anti-inflammatory activity was determined by measuring its effect on NO production in RAW 264.7 macrophages, stimulated with LPS. The results showed that the dry extract maintained its stability over time when stored at a temperature of 4 and 25ºC, demonstrating its biological activity, the content of phenolic compounds, and its physicochemical parameters remain practically invariable. However, when exposed to high temperatures (60 ºC) it was affected. The thermal analysis revelated that the behavior of most of the selected excipients and the dry extract was maintained, which indicates that it did not present incompatibilities, therefore they can be candidates for formulating a microemulsion.

This numerical study is conducted to scrutinize the dual solutions and stability analysis of the flow of Casson nanofluid past a permeable extending/contracting wedge and stagnation point. Momentum, heat and mass transfer behaviors of the Casson nanofluid have been modeled with the use of the Buongiorno nanofluid model. Suitable self-similarity variables are employed to convert the fluid transport equations into ordinary differential equations and the bvp4c MATLAB solver is used to solve the equations. The impacts of active parameters on fluid transport properties are illustrated graphically. The outcomes of the present analysis reveal that the influence of Casson fluid parameter on velocity and temperature distributions obtained from the first and second solutions exhibit the opposite natures. From the stability analysis, it is found that the thermophoresis and Brownian motion effects acquire the same critical point value on Nusselt number. The temperature distribution of the Casson nanofluid is higher over the wedge than stagnation point. The two solutions are found for the limited range of extending/contracting parameter. The detailed stability test is carried out to determine which of the two solutions is physically realizable and stable.

In this brief, a new criterion to determine whether the roots of a polynomial $p(z^{-1})$ with real coefficients are strictly inside the unit circle is presented. It is based on representing the polynomial in a form corresponding to the characteristic polynomial of a closed-loop systems in which all-pass transfer functions are included in both direct chain and feedback loop. The novel and simple criterion for assessing the asymptotic stability of linear discrete-time systems is proved applying the small-gain theorem in the discrete-time domain. [ABSTRACT FROM AUTHOR]

The grid-connected converters are becoming a fundamental building block in the modern power grid, and the stability of grid-connected converters, especially when they are connected to weak grid, has drawn increasing attention. In order to test the interaction with various grid impedances and validate the stability behaviors, more accurate and advanced emulation of grid impedance is becoming an emerging need. However, the existing approaches are still difficult to flexibly shape the grid impedance under medium-to-high frequency range. In this article, a novel configuration for programable impedance emulation of power grid is proposed. The proposed grid emulator is composed of two power electronics converters with special control functions, i.e., the impedance forming converter (IFC) and power supporting converter (PSC). The IFC is designed with a higher switching frequency to virtually emulate different grid impedances under medium-to-high frequency band. On the other hand, the PSC is designed with a lower switching frequency to generate/absorb the power of the converter under test. Besides, a Norton-circuit-based virtual impedance control strategy is introduced to eliminate the derivation term in the control structure of virtual impedance. Finally, the performance of the proposed emulator is verified by various simulations and experimental prototype. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the back module of the existing nursing bed chair is difficult to realize the mutual change between the postures of the nursing bed and wheelchair，a new type of back plate mechanism is proposed. A serial backplane spatial combination mechanism is formed by connecting multiple mechanisms with single function，and its spatial freedom is analyzed to meet the motion demand. The target size is parameterized，and the optimal position of the support connecting rod，backplane and support frame hinge is obtained using the minimum inclusive area method. According to the geometric relationship and statics analysis result of the backplane mechanism，the JC35D electric push rod with rated stroke and working stroke of 175 mm and 230 mm and self-locking force of 1 000 N is used as the driving mechanism. The backplane mechanism of the nursing bed chair is designed according to the optimized parameters and the drive device type，and the overall virtual prototype is assembled by SolidWorks. The simulation finite element analysis plug-in is used to analyze the stress of the backplane under the posture of the nursing bed chair，and the safety and reliability of the structural strength are verified. Under the posture of nursing bed，Adams View software is used to carry out the static rollover simulation test of the mechanism，and the stability requirement of the backplane under the rollover test load is verified.

In the present study, the competitiveness of Iran's agricultural, industrial and in global markets services sectors has been investigated and analyzed. This measurement was taken by calculating four indicators of relative comparative advantage (RCA) at the level of two- and four-digit codes of the International Industrial Standard Classification System for Economic Activities (ISIC) and using the data of Iran-world input-output tables during the period 1996-1995. The results show that out of 3 main subgroups of agriculture, only subdivisions of agricultural products, horticulture, livestock and poultry and hunting and other related activities, and out of 19 subdivisions of industry, only subdivisions of mineral extraction and other related materials, have RCA in all studied years. Other subsections have fluctuations in the presence or absence of comparative advantage, and some have a distinct RCA pattern. This situation has existed in 10 service sub-sectors of the country, but in general, the relative export advantage for service sub-sectors has not been identified in the whole period. In addition, the results of RCA index compatibility tests by performing 3 Cardinal, Ordinal and Dichotomous Measures show that the results of Ordinal tests are more satisfactory than the results of Dichotomous and Cardinal tests and therefore, the present study provides an Ordinal interpretation of RCA indicators in the formation of economic policies. Finally, the results of stability tests show that the indicators of comparative export advantage did not have a stable trend during the period.

Nonthermal plasma (NTP) treatment of food presents a new technology for the industry but raises concerns about lipid oxidation due to the presence of reactive species. Considering the critical role of the degree of unsaturation in lipid oxidation, this study investigates NTP-induced oxidation across various unsaturated lipids. These lipids are six oil samples primarily containing one of the following methylesters: oleate, linoleate, linolenate, arachidonate, eicosapentaenoate, and docosahexaenoate. Samples were treated with a nonthermal surface dielectric barrier discharge. Plasma-induced effects were first examined by classical lipid oxidation indicators, such as the peroxide value and p -anisidine value. The specific volatile oxidation products, including hexanal, nonanal, trans-2-hexenal, and methyl 9-oxononanoate, were determined to further elucidate the impact of ozone-related oxidation. Monitoring the production of selected nonvolatile oxidation products, such as epoxy-, oxo-, and hydroxy fatty acid methylesters, confirmed that plasma treatment facilitated the decomposition of lipid hydroperoxide. Generally, the level of plasma-induced oxidation increased in parallel with the unsaturation degree of the studied samples, except for the quantity of individual volatile carbonyls. The long-term effect of NTP treatment was investigated by a stability test, revealing that the oxidative stability depended on the input gas of plasma treatment, the sensitivity of the treated sample, and the presence of antioxidants. Except for the focus on the NTP impact, this study offered a case study of a comprehensive investigation into lipid oxidation.

In the present, whitening products are most popular in the cosmetics market, and nanoemulsions are effective drug delivery systems through the skin. The objective of this study was to investigate multiple nanoemulsion formulations for lightning skin effects. The method of this study was the selection of active compounds based on synergistic tyrosinase inhibition activity, formulation preparation by low and high energy methods, physicochemical property determination, stability test, cell toxicity, and anti-melanogenesis in cell culture. From the results, it was found that tyrosinase inhibition with substrate l-tyrosine from the mixture of curcumin and alpha-arbutin gave the highest activity with an IC 50 of 63.58 ± 4.99 μM, showed a synergistic effect at a CI value of 0.99, and selected these compounds to develop formulations by the low energy method. However, the most formulations prepared by this method were unstable and phase separated, while the high energy method gave the most formulations with good properties, which were selected for further investigation. The best formulation was 2DS which showed internal droplet morphology in the range of nanometers under a TEM microscope. For 3 months stability test, the formulations had no phase separation and gave the slightly changed values of particle size, polydispersity index (PDI), zeta potentials, and pH values. In addition, multiple nanoemulsions also enhanced the stability of active compounds, with the highest percentage of remaining content of curcumin and arbutin at 94.69 and 90.45 %, respectively at 4 °C for 3 months. In a cell culture test on B 16 F 10 , 2DS at 0.05 g/ml gave no cell cytotoxicity and anti-melanogenesis at 57.75 ± 5.74 %, the same potency as kojic acid at a concentration of 20 μg/ml. Therefore, this study will be useful to prepare multiple nanoemulsions for further development into novel health care products., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

BACKGROUND Sepiolite is a very important non-metallic mineral, which is widely used in aviation, animal husbandry, the chemical industry, environmental protection and other fields. Sepiolite is in great demand and needs a lot of analysis and testing. However, the existing sepiolite reference materials are inadequate and do not satisfy the needs of sepiolite composition analysis. Furthermore, there are no sepiolite reference materials in China, making it necessary to develop one. OBJECTIVES To prepare a reference material for composition analysis of sepiolite whose certified value components cover as many elements as possible. METHODS Sepiolite samples were collected from Xiangtan, Hunan Province. The samples were subjected to primary crushing, coarse-grain sieving, inactivation, fine grinding and fine grain sieving. After passing the initial inspection, samples were bottled and numbered. Random samples were taken for homogeneity test, stability test. 24 components were selected for homogeneity and stability test. RESULTS The results showed that the RSD of 20 components were less than 3%, and the F value of the variance test was less than the critical value of the list[F0.05(29, 60)=1.65], indicating that the homogeneity of the reference material was good. During the investigation period, the contents of 24 components had no significant change, indicating that the standard material was stable. Nine laboratories cooperated with traditional chemical analysis methods and modern instrumental analysis methods to determine the value. The final values were 63 components, covering major, trace and all rare earth elements. The contents of characteristic components MgO and LOI were 18% and 8.55%, respectively. These two components form a certain ladder with the existing reference materials, which can better satisfy the requirements of sepiolite composition analysis. CONCLUSIONS The developed sepiolite reference material can be used as the quality control standards for geological prospecting, geochemical investigation and testing of geological and mineral products, as well as for other industries to analyze similar materials. Moreover, in the process of developing the reference material, improvements and developments to the new methods will provide technical support for the subsequent development of the sepiolite reference material.

Pulmonary drug transport has numerous benefits. Large surface areas for absorption and limited drug degradation of the gastrointestinal system are provided through the respiratory tract. The administration is painless and easy for the patient. Due to their better stability when compared to liquid formulations, powders have gained popularity among pulmonary formulations. In the pharmaceutical sector, quality assurance and product stability have drawn a lot of attention. Due to this, it was decided to perform a long-term stability study on a previously developed, nanosized dry powder inhaler (DPI) formulation that contained meloxicam. Wet milling was implemented to reduce the particle size, and nano spray-drying was used to produce the extra-fine inhalable particles. The particle diameter was determined using dynamic light scattering and laser diffraction. Scanning electron microscopy was utilized to describe the morphology. X-ray powder diffraction and differential scanning calorimetry were applied to determine the crystallinity. In an artificial lung medium, the in vitro dissolution was studied. The Andersen Cascade Impactor was used to investigate the in vitro aerodynamic characteristics. The stability test results demonstrated that the DPI formulation maintained its essential qualities after 6 and 12 months of storage. Consequently, the product might be promising for further studies and development.

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper analytically derives a stability test for the probability distribution of a random variable that follows the Edgeworth–Sargan density, also called Gram–Charlier. The distribution of the test is a weighted sum of Chi-squared densities of increasing degrees of freedom, starting with the standard equivalent Chi-squared under the same conditions. The weights turn out to be linear combinations of the parameters of the distribution and the moments of a Gaussian density, and can be computed exactly. This is a convenient result, since then the probability intervals can be easily calculated from existing Chi-squared distribution tables. The test is applied to assess the weekly solar irradiance data stability for a twelve-year period. It shows that the density is acceptably stable overall, except for some eventual and localised dates. It is also shown that the usual probability intervals implemented in stability testing are larger than those of the equivalent Chi-squared distribution under comparable conditions. This implies that the common upper tail interval values for rejecting the null stability hypothesis are larger. [ABSTRACT FROM AUTHOR]

2D transition metal dichalcogenides (TMDs) have recently received significant attention owing to their superior electrical, optical, and mechanical properties. However, most previous research on TMDs has not focused on their stability against bias and illumination stress. Here, high‐stability tungsten diselenide (WSe2) field‐effect transistors (FETs) are introduced with an ultrathin Al‐assisted alumina (Al2O3) passivation. Through the Al‐assisted Al2O3 passivation, the transport behavior of the WSe2 FETs is converted from p‐type to ambipolar owing to the n‐type doping effect of Al2O3 passivation. Furthermore, the stability of the WSe2 FETs is highly improved against gate bias and illumination stress owing to the effect of Al2O3 film quality on WSe2 by ultrathin Al predeposition (≈1 nm). To compare the stress effect on the electrical characteristics, three types of devices: 1) pristine WSe2 FETs, 2) WSe2 FET with Al2O3 passivation layer, and 3) WSe2 FETs with Al‐assisted Al2O3 passivation layer, are systematically tested with positive gate bias stress (PBS) and positive gate bias illumination stress (PBIS). Finally, an ambipolar inverter composed of Al‐assisted Al2O3 passivated WSe2 FETs is demonstrated. This study proposes a promising approach that improves the stability of TMD‐based FETs for next‐generation logic applications. [ABSTRACT FROM AUTHOR]

This numerical study is conducted to scrutinize the dual solutions and stability analysis of the flow of Casson nanofluid past a permeable extending/contracting wedge and stagnation point. Momentum, heat and mass transfer behaviors of the Casson nanofluid have been modeled with the use of the Buongiorno nanofluid model. Suitable self-similarity variables are employed to convert the fluid transport equations into ordinary differential equations and the bvp4c MATLAB solver is used to solve the equations. The impacts of active parameters on fluid transport properties are illustrated graphically. The outcomes of the present analysis reveal that the influence of Casson fluid parameter on velocity and temperature distributions obtained from the first and second solutions exhibit the opposite natures. From the stability analysis, it is found that the thermophoresis and Brownian motion effects acquire the same critical point value on Nusselt number. The temperature distribution of the Casson nanofluid is higher over the wedge than stagnation point. The two solutions are found for the limited range of extending/contracting parameter. The detailed stability test is carried out to determine which of the two solutions is physically realizable and stable. [ABSTRACT FROM AUTHOR]

Abstract 2D transition metal dichalcogenides (TMDs) have recently received significant attention owing to their superior electrical, optical, and mechanical properties. However, most previous research on TMDs has not focused on their stability against bias and illumination stress. Here, high‐stability tungsten diselenide (WSe2) field‐effect transistors (FETs) are introduced with an ultrathin Al‐assisted alumina (Al2O3) passivation. Through the Al‐assisted Al2O3 passivation, the transport behavior of the WSe2 FETs is converted from p‐type to ambipolar owing to the n‐type doping effect of Al2O3 passivation. Furthermore, the stability of the WSe2 FETs is highly improved against gate bias and illumination stress owing to the effect of Al2O3 film quality on WSe2 by ultrathin Al predeposition (≈1 nm). To compare the stress effect on the electrical characteristics, three types of devices: 1) pristine WSe2 FETs, 2) WSe2 FET with Al2O3 passivation layer, and 3) WSe2 FETs with Al‐assisted Al2O3 passivation layer, are systematically tested with positive gate bias stress (PBS) and positive gate bias illumination stress (PBIS). Finally, an ambipolar inverter composed of Al‐assisted Al2O3 passivated WSe2 FETs is demonstrated. This study proposes a promising approach that improves the stability of TMD‐based FETs for next‐generation logic applications.

Aims: The microbial pigment can be the best promising alternative to replace synthetic colorant. However, due to the high cost of synthetic medium for microbial pigment production, there is a need to develop a new low-cost medium of bacterial pigment production. This study aims to investigate the potential of banana and papaya peels as alternative lowcost substrates for a carotenoid-producing bacterium, B12 strain (bacteria strain isolated from Holothuria (Lessonothuria) pardalis). Methodology and results: B12 strain identified as an aerobic bacterium with non-motile, diplobacilli shaped and Grampositive bacteria. The fermentation was optimized with different parameters included the effect of temperature, time, concentrations, pHs, carbon and nitrogen sources to find the optimum relative pigment concentration produced by B12. The results showed that the B12 strain produced the highest relative pigment concentration measured at 450 nm when the strain was cultivated at 37 °C and pH 7 in the culture medium incorporated with the combination of dried papaya peels and banana peels (100% v/v with ratio 1:1) at 72 h of incubation. Lactose, peptone and yeast were observed as the best carbon and nitrogen sources to increase the pigment concentration of B12 strain. Stability of the pigment was studied at different physiochemical stress, and it showed the pigment obtained from dried papaya and banana substrates can tolerate and stable under stress condition. Conclusion, significance and impact of study: This can be concluded that the combination of dried papaya and banana peels worked well as substrate and can be utilized as a fermentation medium to replace the synthetic medium which is more expensive and uneconomical for industry application. Besides, it also helps in managing waste and solving the pollution problem due to the increasing of biochemical oxygen demand (BOD) and chemical oxygen demand (COD). [ABSTRACT FROM AUTHOR]

Copyright of Xinjiang Agricultural Sciences is the property of Xinjiang Agricultural Sciences Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Perovskite solar cells (PSCs) have emerged as a promising technology for next‐generation photovoltaic devices because of their ease of fabrication and high power conversion efficiency (PCE). The main obstacle that limits the commercialization of large‐area PSCs is the lack of suitable solution‐processable low‐temperature fabrication methods and the perovskite material's chemical stability. With an increase in the active area of the cell, the defect states and the series resistance of the device increase, which is undesirable. We have demonstrated a repeatable fabrication method of small (0.25 cm2) and large (2.0 cm2) active area devices with Au and Cu as back contact electrodes. Small area perovskite devices with Cu and Au contact electrodes showed a PCE of 9.87% and 10.42%, respectively. When scaled up to 2.0 cm2, the devices showed a minor drop in the open‐circuit voltage, but a significant decrease in photocurrent was observed. Large‐area PSCs with Cu and Au contacts displayed a PCE of 5.61% and 5.92%, respectively. External quantum efficiency measurements at four different points provided similar results, thus confirming the uniformity of large‐area devices. The stability of large‐area devices under ambient environment conditions was tested for more than 7 weeks. Gold‐based PSC retained almost 75% of its initial PCE when stored in ambient conditions for 50 days, whereas Cu‐based devices showed a significant decrease in efficiency in the same period. Degradation in efficiency of PSCs occurred primarily due to the loss in photocurrent arising from active layer degradation. Simulations of perovskite devices carried out using Solar Cell Capacitance Simulator (SCAPS)‐1D software also showed that similar efficiencies of PSCs may be obtained using Cu, instead of Au, as the low‐cost metal contact. Novelty Statement: Large‐area perovskite solar cells (PSCs) based on gold and copper metal contacts have been fabricated, and copper contacts provide efficiencies comparable with the values obtained with gold contacts. The study shows that copper can be used as a low‐cost alternative to gold to fabricate large‐area, high‐efficiency PSCs. Stability testing under ambient conditions has been carried out for 50 days to compare the performance of gold‐ and copper‐based large‐area PSCs. [ABSTRACT FROM AUTHOR]

This paper presents a novel planar proton exchange membrane fuel cell (PEMFC) stack designed for portable electronic devices, consisting of twenty homemade membrane electrode assemblies (MEAs) arranged on a planar surface and three printed circuit boards (PCBs, including anode, interlayer and cathode PCBs) used to load these MEAs. The current collectors and electrical connectors are manufactured using printed circuit technology. The inlet holes of reaction gases are also machined on PCB substrates. The output performance tests are performed on the MEAs and the assembled planar PEMFC stack. The results show that the power densities of the MEAs and the planar PEMFC stack are 0.6 W/cm2 and 0.361 W/cm2 at rated voltage under ambient temperature and forced convection air conditions, respectively. The stability tests are also conducted on the planar PEMFC stack, and the results show no significant fluctuations in output current. The feasibility of the application of planar PEMFC stacks in portable electronic devices is preliminarily demonstrated, and the improvement directions for further improving the output performance are proposed accordingly. • A planar PEMFC stack is designed and evaluated experimentally. • The planar PEMFC stack is constructed based on printed circuit technology. • The power densities of the planar PEMFC stack are 0.6 W/cm2 at rated voltage. • Discharge and stability tests reveal the good application feasibility of planar PEMFC stack. [ABSTRACT FROM AUTHOR]

This work aims at examining the thermophoresis and Brownian motion characteristics on the stagnation point flow of Cross nanofluid over a permeable stretching/contracting surface. Flow equations are modelled by means of the Buongiorno nanofluid model. The transformed non-linear fluid transport equations are solved numerically through Runge-Kutta Fehlberg (RKF) approach. The temporal stability test is executed to reveal the behaviour of dual solution that arises for various initial guesses. To validate the present model, first and second solutions are compared with earlier published works which found good agreement. The fluctuations of velocity, heat and mass transfer distributions are scrutinized through the graphs with active parameters such as Wessienburg number, Brownian motion, Eckert number, and thermophoresis. The results exposed that the Brownian motion declines the rate of heat transfer for the first solution. Cross nanofluid velocity amplifies by rising Weissenberg number. By the impact of Eckert number, the second solution has a higher magnitude than the first solution. For the first solution, the cross nanofluid velocity rises when increasing the suction/injection parameter. [ABSTRACT FROM AUTHOR]

Amesiodendron chinense (Merr.) Hu oil is reported to use for the treatment of skin disease by Thai folk medicine. Its hydrophilic-lipophilic balance (HLB) value is very important for developing a stable cream formulation. This study aimed to determine the required hydrophilic-lipophilic balance (rHLB) value of Amesiodendron chinense (Merr.) Hu oil and to develop a stable cream formulation. Herbal cream containing Amesiodendron chinense (Merr.) Hu oil was prepared by phase inversion temperature technique using water, Tween80, and Span60. The first series of 11 emulsions with HLB values ranging from 5.0 to 15.0 and the second series of eight emulsions with a smaller interval in HLB values from 5.0 to 7.8 were prepared. rHLB of coconut oil was also determined for validation of methodology. Creaming index is the established parameter to determine rHLB and to develop stable emulsion. Emulsions with optimum emulsifier concentration resulted in less percentage-creaming index. Utilizing determined rHLB, Amesiodendron chinense (Merr.) Hu cream was formulated and evaluated for different physical parameters including viscosity, color, odor, texture, and pH. Finally, the results showed the rHLB value of coconut oil and Amesiodendron chinense (Merr.) Hu oil was 5.4 and 6.2, respectively. The stable creams were developed with a 3% emulsifier. Physical parameters were found to be consistent over 6 cycles of accelerated stability test under 4 and 45○C. Physical properties of cream evaluation ensure the stability of the developed cream. rHLB value of Amesiodendron chinense (Merr.) Hu oil was exhibited, and the stable creams were successfully formulated by utilizing determined rHLB. [ABSTRACT FROM AUTHOR]

Our study focuses on the valuation of Spirulina, which can contain up to 70% of protein, in the manufacture of a dietary product. It aims to elaborate a hyper-protein energy drink of grape juice having a significant nutritional intake .Our study aims to show the effect of the incorporation of spirulina on the physicochemical parameters of a grape juice at different doses (0.1g/l - 0.3g/l - 0.5g/l - 0.7g/l) compared to a control drink and evaluation of its nutritional value. Several analyzes were carried out The Physicochemical analyzes - acidity, Brix, pH, and density with reference to Algerian standards, as well as sensory analyzes ;stability testing .The statistical analysis ( Newman-keuls test) showed that they are not significantly different between all parameters at the probability 0.05 probability level. The physico-chemical analyses obtained from different products are in agreement with Algerian standards.Indeed, the juice has a certain richness in proteins (31%); it is therefore considered a high protein product. A good microbiological quality of the juice was revealed. The F3 formulation (0.5g) is judged to be good, and well appreciated by the tasting panel. Its stability test for 4 weeks at 22°C showed that formulation F3 (0.5g) is a stable juice. There is a significant effect ( p < 100) of the dose of spirulina incorporated on the parameters studied ( Acidity, pH, Density, refractive index ). The enrichment of grape juice by spirulina allowed us to obtain a dietetic grape juice, a stable and hyper protein with a protein level of 31%. [ABSTRACT FROM AUTHOR]

BACKGROUND With the increased attention paid for the construction of ecological civilization, a comprehensive survey of natural resources is imperative, and new requirements for biological reference materials have also been put forward. At present, relevant research work has been widely carried out. The comprehensive investigation of natural resources, agricultural products and food safety evaluation all need to accurately test the element composition of biological samples, and biological reference materials are needed as the basis for the comparison and traceability of biological components. The demand for biological matrix reference materials has increased significantly. As one of the main foods, the food safety of rice has been paid more and more attention. It is of great practical significance to carry out accurate analysis of the chemical components in rice. Therefore, the demand for rice is particularly prominent, but the rice reference materials for composition analysis are still lacking. OBJECTIVES To develop rice certified reference material (GBW10010a) and compare it with the data characteristics of GBW10010. METHODS The rice certified reference material (GBW10010a) was prepared in strict accordance with relevant specifications. The collected candidates were prepared through coarse crushing, drying, fine crushing, sieving, blending and other steps. The particle size distribution was detected by BT-9000ST laser particle size analyzer. 15 bottle samples were randomly selected and homogeneity testing was carried out by ICP-MS and ICP-OES, etc. The data were statistically calculated by one-way ANOVA, indicating good homogeneity of the samples. The long-term stability of the standard material under the specified storage conditions was investigated. The linear model was used to evaluate the stability of the sample. The determination of 60 components was carried out by means of ICP-MS, ICP-OES, AFS, COL, VOL, XRF, IC and other Analytical test methods. RESULTS The rice reference material prepared in this research has diverse fixed value components, accurate and reliable measurement values, and meet the requirements of national first-level reference material. GBW10010a has a total of 54 main trace elements. 39 elements have certified values and uncertainties and 15 elements only have reference values. The content of heavy metal elements such as As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Zn in GBW10010a decreased significantly, among which Cd, Cu, and Zn decreased by about 39%, 43% and 38.7%, respectively. CONCLUSIONS To a certain extent, the values reflects the improvement of farmland ecological environment. Compared with the original GBW10010, the total number of certified value elements has increased by 6 items, including Ag and Nb (Nb gives reference values). Moreover, the uncertainty of each element is reduced, including biological-related elements Al, Cd, Cu, Fe, K, Mg, Mo, Na, P, Pb, Se, and Zn. The reduction indicates the technological advancement of the geological analysis and the improvement of the certified value level. In addition, the content of heavy metal elements in GBW10010a decreased significantly, reflecting the improvement of farmland ecological environment. The designated elements of the reference materials cover most of the main and trace elements with biological effects, and are suitable for the calibration of analytical instruments, evaluation of analytical methods, and monitoring analytical quality during agricultural ecological environment geochemical surveys and evaluation, biological sample analysis, agricultural product quality and food safety evaluation.