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GNSS-RTK offers numerous advantages and broad prospects in structural dynamic monitoring in civil engineering. However, in practical applications, GNSS-RTK accuracy is susceptible to the monitoring environments, causing actual monitoring accuracy to fall below its calibrated accuracy. This study investigates the monitoring accuracy and spectral characteristics of GNSS-RTK based on stability tests under different environments related to reflection and obstruction conditions (i.e., concrete, grass, an obstructed balcony, and a water area). The findings indicate that in open environments of grass, concrete, and water, the standard deviation (STD) of GNSS-RTK monitored displacement is below 8 mm, its accuracy meeting the specifications of structural health monitoring. In the obstructed balcony environments, GNSS-RTK signals exhibit amplitude jumps, resulting in lower accuracy; however, during non-jump intervals, the STD of monitored displacement is below 10 mm, satisfying the structural health monitoring accuracy requirements. Moreover, the amplitudes of GNSS-RTK displacements in the concrete, grass, and water areas are basically consistent with the calibration accuracy of ±10 mm in the horizontal direction and ±20 mm in the elevation direction, while the amplitudes of GNSS-RTK displacements in the obstructed balcony condition are far greater than the calibration accuracy. The spectral analysis of GNSS-RTK signals reveals that multipath errors in concrete, grass, and obstructed balcony environments are primarily concentrated in the low-frequency range within 0.04 Hz, while the internal white noise of the instrument is widely and evenly distributed across the whole frequency domain. Based on these findings, adaptive methods, such as filter methods and multipath error correction techniques, are proposed for the de-noising of GNSS-RTK background noise. [ABSTRACT FROM AUTHOR]

The stability test of multi-station precision machining fixtures can improve the safety of multi-station precision machining fixture. This paper puts forward a stability test method of multi-station precision machining fixtures based on the pressure pulsation amplitude test. The fundamental frequency characteristic detection of airflow pulsation is adopted to collect the stability characteristic parameters of multi-station precision machining machine clamps, and the wave number analysis model of airflow pulsation in the stable state of multi-station precision machining machine clamps is constructed. The time domain characteristic parameter analysis and spectrum gain control are adopted to realize the stability condition parameter analysis and spectrum characteristic decomposition of multi-station precision machining machine clamps. The end-face pulsation attenuation characteristic method of detection is followed to realize noise reduction of the stable air pulsation attenuation signal of multi-station precision machining fixture, and the rotor meshing frequency component of the stable air pulsation attenuation signal of multi-station precision machining fixture is extracted. The multi-scale wavelet air pulsation attenuation signal decomposition is adopted to realize the correlation spectrum characteristic detection of the signal, and the multi-dimensional space fusion is employed to realize signal characteristic clustering, thus realizing the stability detection of multi-station precision machining fixture. The test output shows that the proposed method has better convergence and strong feature clustering in the stability detection of multi-station precision machining machine fixtures, which improves the confidence level of multi-station precision machining machine fixture failure instability detection. [ABSTRACT FROM AUTHOR]

The chemical mechanical polishing/planarization (CMP) is essential for achieving the desired surface quality and planarity required for subsequent layers and processing steps. However, the aggregation of slurry particles caused by abrasive materials can lead to scratches, defects, increased surface roughness, degradation the quality and durability of the finished surface after milling processes during the CMP process. In this study, ceria slurry was prepared using polymer dispersant with zinc salt of ethylene acrylic acid (EAA) copolymer at different contents of 5, 6, and 7 wt% (denoted as D5, D6, and D7) to minimize particle aggregation commonly observed in CMP slurries. Among them, the D7 sample exhibited smaller particle sizes compared to commercial ceria slurry, which was attributed to the influence of the carboxyl groups (-COOH) of the polyacrylic acid polymer coating the ceria particles. It is believed that the polymer dispersant more effectively adsorbs onto the particle surfaces, increasing electrostatic repulsion between particles and thereby reducing particle size. Furthermore, the stability of the prepared slurry was evaluated under extreme conditions over three months at 25 °C (both open and closed conditions), 4 °C, and 60 °C. The D7 slurry remained stable with no significant changes observed. In addition, the prepared D7 ceria slurry exhibited a slightly higher removal rate (RR) and better uniformity, which can be attributed to the smaller particle sizes of the ceria nanoparticles compared to those in the commercial slurry. This suggests that the colloidal stability of the D7 ceria slurry is superior to that of the commercial ceria slurry. [ABSTRACT FROM AUTHOR]

The authors use a temporal stability analysis to examine the hydrodynamics performance of flow response quantities to investigate the impacts of pertained parameters on Casson nanofluid over a porous shrinking wedge. Thermal analysis is performed in the current flow with thermal radiation and the viscous dissipation effect. Boungiorno's model is used to develop flow equations for Casson nanofluid over a shrinking wedge. An efficient similarity variable is used to change flow equations (PDEs) into dimensionless ordinary differential equations (ODEs) and numerical results are evaluated using MATLAB built-in routine bvp4c. The consequence of this analysis reveals that the impact of active parameters on momentum, thermal and concentration boundary layer distributions are calculated. The dual nature of flow response output i.e. Cƒx is computed for various values of βT = 2.5, 3.5, 4.5, and the critical value is found to be -1.544996, -1.591, and -1.66396. It is perceived that the first (upper branch) solution rises for the temperature profile when the value of thermal radiation is increased and it has the opposite impact on the concentration profile. Thermal radiation has the same critical value for Nux and Shx. The perturbation scheme is applied to the boundary layer problem to obtain the eigenvalues problem. The unsteady solution ƒ (η, τ) converges to steady solution ƒo (η) for τ → ∞ when γ ≥ 0. However, an unsteady solution ƒ (η, τ) diverges to a steady solution ƒo (η) for τ → ∞ when γ < 0. It is found that the boundary layer thickness for the second (lower branch) solution is higher than the first (upper branch) solution. This investigation is the evidence that the first (upper branch) solution is stable and reliable. [ABSTRACT FROM AUTHOR]

The authors use a temporal stability analysis to examine the hydrodynamics performance of flow response quantities to investigate the impacts of pertained parameters on Casson nanofluid over a porous shrinking wedge. Thermal analysis is performed in the current flow with thermal radiation and the viscous dissipation effect. Boungiorno's model is used to develop flow equations for Casson nanofluid over a shrinking wedge. An efficient similarity variable is used to change flow equations (PDEs) into dimensionless ordinary differential equations (ODEs) and numerical results are evaluated using MATLAB built-in routine bvp4c. The consequence of this analysis reveals that the impact of active parameters on momentum, thermal and concentration boundary layer distributions are calculated. The dual nature of flow response output i.e. Cfx is computed for various values of βT=2.5,3.5,4.5, and the critical value is found to be −1.544996, −1.591, and −1.66396. It is perceived that the first (upper branch) solution rises for the temperature profile when the value of thermal radiation is increased and it has the opposite impact on the concentration profile. Thermal radiation has the same critical value for Nux and Shx. The perturbation scheme is applied to the boundary layer problem to obtain the eigenvalues problem. The unsteady solution f(η,τ) converges to steady solution fo(η) for τ→∞ when γ≥0. However, an unsteady solution f(η,τ) diverges to a steady solution fo(η) for τ→∞ when γ

Background: This study presents a comprehensive study on applying the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use Q1A R2 guideline for conducting stability tests on new drug substances and products. Materials and Methods: This study focused on the stability of multivitamin syrup under specific storage conditions, following ICH guidelines. The syrup was subjected to various tests, including pH measurement, weight per mL determination, microbial limit testing and assay analysis. Along with OOS, OOT and root cause analysis. Results: Showed that the syrup maintained its yellow color, met pH specifications and had the appropriate weight per mL. Microbial limit tests revealed no presence of harmful bacteria and assay analysis confirmed the purity and quantity of the components in the syrup. A survey on tablet preparations also demonstrated stability and quality. Conclusion: Overall, the stability studies indicated that the multivitamin syrup met all specifications and was considered stable. These findings contribute to ensuring the safety and effectiveness of the product throughout its shelf life. [ABSTRACT FROM AUTHOR]

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]

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]

Copyright of China Fiber Inspection / Zhongguo Xian-Jian 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.)

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.)

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]

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.)

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 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]

[Display omitted] • Binary RuO 2 -TiO 2 and ternary RuO 2 -TiO 2 -IrO 2 MMO are coated on Ti by a simple approach. • All prepared Ti/MMO anodes exhibit significant activity toward the MOR in aq. KOH. • Ti/70%RuO 2 -30%TiO 2 and Ti/70%RuO 2 -25%TiO 2 -5%IrO 2 reveal the best performance for MOR. • Ternary catalyst has higher C dl , Γ* , D values, and lower onset potential than the binary. • MOR is zero and first-order for fuel and KOH at both catalysts, with high stability. In this study, binary and ternary mixed metal oxide (MMO) electrodes were fabricated and examined as promising electrocatalysts for direct methanol oxidation reaction (MOR). The binary (RuO 2 -TiO 2) and ternary (RuO 2 -TiO 2 -IrO 2) MMOs with various molar ratios were coated on Ti substrate via an eco-friendly simple co-deposition method. The optimal compositions were assessed by cyclic voltammetry (CV) as Ti/70 %RuO 2 -30 %TiO 2 and Ti/70 %RuO 2 -25 %TiO 2 -5 %IrO 2. Multiple physicochemical techniques were utilized to characterize these two catalysts. At 50 mV/s scan rate, the binary catalyst showed favorable activity for the MOR with a minimal onset potential of 0.20 V and a maximum current density of 35.46 mA/cm2 in 4 M KOH + 1 M CH 3 OH. However, the ternary catalyst surpassed the binary, displaying an onset potential of 0.10 V and a maximum current density of 67.69 mA/cm2 in 4 M KOH + 2 M CH 3 OH. In the meantime, the two electrocatalysts exhibited remarkable stability in long-term 20 h chronoamperometric (CA) electrolysis at their optimal conditions. Various physical traits were further estimated for the two proposed anodes to compare their relative capabilities. The results for the binary and ternary catalysts were, respectively, the double-layer capacitance (C dl) 54.30 and 63.43 mF/cm2, the surface excess (Γ*) 1.55 × 10-8 and 1.92 × 10-8 mol/cm2, and the diffusion coefficient (D) 1.09 × 10-8 and 5.43 × 10-8 cm2/s. This hints at the vital role of adding IrO 2 in the MMO binary catalyst to ameliorate its activity toward the MOR process in an alkaline environment. [ABSTRACT FROM AUTHOR]

Preparation of serum in the form of extract nanoemulsions allows effective delivery of active ingredients to the skin due to the more stable nanoemulsions, lower viscosity, transparent visual aspects, and high surface area caused by the small globule size. This study aims to obtain an optimal 96% ethanol concentration and sonication time in forming stable nanoemulsions at temperatures of 4° and 40°C with an active ingredient of moringa leaf extracts. The experiment was performed in four sets of 96% ethanol concentration (5%, 10%, 15%, and 20%) and three sonication periods (30, 60, and 90 minutes). The freeze-and-thaw method was utilized to evaluate the stability of the nanoemulsions. The analysis unveiled that a 96% ethanol concentration of 10% and a sonication time of 46 minutes was the most appropriate formula, generating a particle size of 30.49 nm with a volume of 73.35%. At the same time, the stability test of the preparation revealed that storage time significantly affected the pH response. However, it did not significantly affect the viscosity response.

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.

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.

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.

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]

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]

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.

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]

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]

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.)

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]

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.