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Solutions to most nonlinear ordinary differential equations (ODEs) rely on numerical solvers, but this gives little insight into the nature of the trajectories and is relatively expense to compute. In this paper, we derive analytic solutions to a class of nonlinear, homogeneous ODEs with linear and quadratic terms on the right-hand side. We formulate a power series expansion of each state variable, whose function depends on the eigenvalues of the linearized system, and solve for the coefficients using some linear algebra and combinatorics. Various experiments exhibit quickly decaying coefficients, such that a good approximation to the true solution consists of just a few terms. [ABSTRACT FROM AUTHOR]

The suspension of nanoparticles into the conventional heat transfer fluids has been sampled as means of improving heat transfer efficacy of fluid. The current communication is aimed to discuss the unequal diffusion coefficients of reactant A (bulk fluid) and reactant B (catalyst at the wall) for the Eyring-Powell liquid motion over a surface with variable thickness. The effects such as variable fluid properties, stratification and gyrotactic microorganisms have been considered into account. The equations governing the fluid motion are transformed to the ordinary differential equations with the appropriate similarity transformations. The solutions of the system of transformed governing equations have been developed using the reliable numerical technique Runge-Kutta integration. It is concluded from the current study that, when gyrotactic microorganisms density and thermal stratifications considered as 0.1, the augmentation of Eyring-Powell fluid parameter enhances the velocity distribution and diminution of temperature distribution. Furthermore, when homogeneous reaction parameter rises from 0.1 to 1.0, a conspicuous augmentation is noticed in both concentration distribution of homogeneous and bulk distribution of heterogeneous at the wall. [ABSTRACT FROM AUTHOR]

The transdermal drug delivery system (TDDS) was created with the main goals of achieving extended pharmaceutical release, increasing bioavailability, and enhancing patient adherence. The matrix dispersion transdermal patch works by dispersing the drug and polymers in a solvent, which is then evaporated to leave a homogenous drug-polymer matrix. The goals of the present study were on designing and formulating TDDS for tirzepatide and afterwards assessing their in vitro performance characteristics. In diabetes mellitus, the pancreas either produces inadequate amounts of insulin or the body is unable to properly use the insulin that is generated. More than 415 million people worldwide have diabetes, and it is anticipated that by 2040, that number would reach 642 million. By 2030, diabetes will surpass heart disease as the seventh largest cause of death, according to the WHO. [ABSTRACT FROM AUTHOR]

Investigations carried out on cellular steel beams so far were mainly focused on the behavior of non-composite homogeneous sections. Hybrid I-beams are built-up sections where different steel grades are used for flanges and web parts. But perforated hybrid hot-rolled I-sections, where the top and bottom T sections would have different steel grades, can be achieved due to their cutting process. This paper presents a comprehensive parametric study focusing on the inelastic behavior of hybrid and homogeneous cellular steel beams made from hot-rolled parent sections. Finite element modeling using ABAQUS software was employed to validate previously tested hybrid and homogeneous cellular steel beams made from hot-rolled sections. To observe the effect of hybrid sections; the results of hybrid cellular steel beams were compared to the homogeneous ones of the same geometry but with different materials property. A broad spectrum of parent sections (section ratio), restraining conditions, spacing to opening ratio, span lengths, and various steel grades were included in the analysis. Results showed that the upper Tee is mainly the governing part in cellular beams. Moreover, the use of hybrid cellular beams with successive steel grades showed more compatible results compared to sections with non-successive grades for both restrained and unrestrained sections failing under global buckling. According to Eurocode 3 design rules, a set of modified equations were proposed to be used for the Lateral Torsional Buckling resistance calculations of hybrid cellular beams made from hot-rolled sections. [ABSTRACT FROM AUTHOR]

In this note, we prove the existence of homogeneous gradient solitons for the G_2-Laplacian flow by providing the first known example of this type. This result singles out the G_2-Laplacian flow as the first known geometric flow admitting homogeneous gradient solitons on spaces that are one-dimensional extensions in the sense of Petersen and Wylie [Differential Geom. Appl. 84 (2022), Paper No. 101929, 29]. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the concept of generalized pseudo-base in generalized topological spaces, and using this concept, we study the product of g-Volterra space and weakly g-Volterra space in generalized topological spaces. In addition, we study the product of g-Baire space with g-Volterra space in generalized topological spaces. [ABSTRACT FROM AUTHOR]

There have been a lot of interest in developing synthesis methods for the preparation of homogeneous multicomponent metal oxides for wide range of applications in the literature. One synthesis method of metal oxides was patented by Pechini in 1967, which involved an intermediate metal containing resin formation followed by calcination. Extensive research based on this patent took place over last few decades. However, many works in past would include confusions and contradictions among so called “sol–gel methods”, “co-precipitation methods” and “solution routes”. Even now, the confusion between the sol–gel method and the method described in the patent by Pechini prevails in the literatures. Interestingly, (i) the synthesis method described by Pechini is different from the so-called sol–gel methods, (ii) chemically, complex formation and polymerization reactions take place at the early stage and (iii) the performance of materials produced by this method is excellent for many applications. Herein, based on the extensive research, a scientific name such as the polymer complex (PC) method has been proposed. Furthermore, the general development and advancement of this method and recent advances in the area of thermoelectric, energy storage and photocatalytic materials preparation, respectively involving the PC method have been discussed.

The rational design of green chemical, low-cost, and highly efficient solid-state electrolytes for Li-metal anode is a promising but still challenging strategy for preventing Li dendrite growth and developing safe and ultralong cycle life Li-metal batteries. Herein, a homogeneous composite solid polymer electrolyte (CSPE) is fabricated with water as the ideal dispersion medium, hectorite (Ht) as nanofiller, and poly (ethylene oxide) (PEO) as the matrix, to guide uniform Li plating/stripping. Benefiting from the merit of Ht can form uniformly dispersed nanosheets in water, the obtained CSPE inheres to a low melting point, robust mechanical property, and high Li+ transference number. Moreover, the fabricated Li symmetric battery using PEO-Ht-LiClO4 CSPE keeps cycling steadily for 4 000 h. The well demonstrated water-based CSPE paves the way for developing low-cost, environmentally friendly, and safe solid-state electrolytes for Li-metal batteries.

AbstractThis article aims to demonstrate the accuracy and robustness of the strain based approach in analyzing pressurized FGM cylinders with arbitrarily varying material properties. A sector in-plane finite element in the polar coordinate system based on this approach is employed. The obtained results are compared with the analytical solutions available in the literature, and a good accuracy was shown. In addition, this element can easily simulate the behavior of FGM without the need for dividing the cylinder into homogeneous layers. This investigation would be helpful in the design and analysis of hollow cylinders made of functionally graded materials. [ABSTRACT FROM AUTHOR]

This study examines the asymmetric impact of climate policy uncertainty (CPU) under heterogeneous stock market conditions in the Chinese stock market. The study adopted two econometrics techniques of panel generalized autoregressive condition heteroscedasticity and panel quantiles via moment models. The results show that the markets' response to CPU is homogeneous and varies across bearish, normal, and bullish conditions. The findings established that CPU is a risk factor, and its pricing is asymmetric as it depends on market conditions. The results also suggest that CPU is one of the predictors of future returns, but the forecast may be largely driven by market conditions. The study further shows how market's response to CPU varies which often complicates prediction as the direction of response is determined by the market's condition. [ABSTRACT FROM AUTHOR]

The primary objectives of this paper can be categorized into two main aspects. First, we investigate the existence of a closed hypersurface in Euclidean space with prescribed mixed quotient type Weingarten curvature. This result can be viewed as an improvement of the result of Chen-Tu-Xiang [12, Theorem 1.1]. Second, we study the homogeneous mixed Weingarten curvature problem and the convexity of the corresponding hypersurface. [ABSTRACT FROM AUTHOR]

Facial expression recognition (FER) plays a crucial role in understanding human emotions and is becoming increasingly relevant in educational contexts, where personalized and empathetic interactions are essential. The problems with existing approaches are typically solved using a single deep learning method, which is not robust with complex datasets, such as FER data, which have a characteristic imbalance and multi-class labels. In this research paper, an innovative approach to FER using a homogeneous ensemble convolutional neural network, called HoE-CNN, is presented for future online learning education. This paper aims to transfer the knowledge of models and FER classification using ensembled homogeneous conventional neural network architectures. FER is challenging to research because there are many real-world applications to consider, such as adaptive user interfaces, games, education, and robot integration. HoE-CNN is used to improve the classification performance on an FER dataset, encompassing seven main multi-classes (Angry, Disgust, Fear, Happy, Sad, Surprise, Neutral). The experiment shows that the proposed framework, which uses an ensemble of deep learning models, performs better than a single deep learning model. In summary, the proposed model will increase the efficiency of FER classification results and solve FER2013 at a accuracy of 75.51%, addressing both imbalanced datasets and multi-class classification to transfer the application of the model to online learning applications. [ABSTRACT FROM AUTHOR]

Purpose: The examination of the behavior of wave propagation through different kinds of materials under various mathematical models certainly brings out new properties of those materials to the fore. In this contribution, the circular-crested Lamb-type waves in an isotropic homogeneous, elasto-thermal plate with voids sandwich-packed by inviscid liquid layers have been examined in the context of Lord–Shulman and Green–Lindsay generalizations. Methods: Helmholtz's decomposition principle has been used to separate the solenoidal part and the lamellar part of the waves. The normal mode analysis technique has been used to obtain solutions to governing equations. With the help of solutions, the obtained partial differential equations have been converted to ordinary differential equations to find the eigenvalues of the elasto-porothermal plate bordered with inviscid liquid layers. The problem has also been solved from a numerical point of view and the results have been portrayed graphically. Results: The transverse horizontal wave being unaltered due to voids and temperature gradient gets separated from the coupled system corresponding to elastic waves (compressional and transverse vertical), thermal waves, and wave motion due to voids. Apart from that, each layer of liquid possesses one longitudinal wave. The frequency equations have been derived for the flexural and longitudinal wave modes by solving the stiffness matrix. The inviscid fluid and voids decrease the magnitude of phase velocity and attenuation coefficient. Thermal relaxation times have a small impact on wave propagation. Conclusions: The problem of circular-crested Lamb-type waves has been solved mathematically which lays a theoretical foundation for further study of Lamb-type wave propagation in plates. The present work may find applications in many fields such as the petroleum industry, earthquake engineering, soil dynamics, hydrology, as well as biomechanics. [ABSTRACT FROM AUTHOR]

This paper presents the successful homogeneous processing of Y 2 O 3 green compacts by pressure-assisted alcoholic slip casting (PASC) method for the preparation of high-quality Y 2 O 3 transparent ceramics. The optimal Y 2 O 3 alcoholic slurry with 1.5 wt% polyethyleneimine as the dispersant and the solid load of 30.69 vol% was employed for PASC. Compared to dry-pressing green compact, PASC-prepared green compact exhibits high homogeneity and sinterability with less microstructural defects, such as large pores or particle agglomeration. Based on these advantages, we successfully prepared transparent Y 2 O 3 ceramic by simply vacuum sintering with low porosity, excellent optical homogeneity, and high in-line transmittance of 80.4% at the wavelength of 600 nm. [ABSTRACT FROM AUTHOR]

Purpose: In the present paper, effect of porosity and its distributions on free vibration of single-layered and sandwich plates with and without a hole having different gradation laws of material are investigated. Three different laws for material properties variation along the thickness direction of the core are considered, viz. power law, sigmoid law, and exponential law. Methods: The distributions of porosity for the above-mentioned functionally graded core are as homogeneous, uneven symmetric, and uneven unsymmetric. A MATLAB program is developed for the present analysis, and some results are compared with that of the literature to verify the efficiency of the computer program. Results an Conclusions: Parametric studies are done to revels the effect of elastic foundation, hole radius, boundary conditions, plate thickness ratio, grading power index, and porosity volume fraction on nondimensionalized natural frequency (NNF). [ABSTRACT FROM AUTHOR]

Antinuclear antibodies (ANAs) are essential diagnostic markers in systemic autoimmune rheumatic diseases. Among the 30 ANA patterns, homogeneous (AC-1) and dense fine speckled (AC-2) should be focused on owing to their somewhat indistinct presentation in immunofluorescence imaging and distinct correlation with clinical conditions. This study aimed to develop a flowchart to guide discrimination between AC-1 and AC-2 patterns and to re-evaluate ANA samples according to this flowchart to verify its detection ability. We re-evaluated immunofluorescence imaging of 62 ANA blood samples simultaneously subjected to solid-phase assays for autoantibodies against dsDNA, nucleosomes, histones, and DFS70. The results showed statistically significant odd ratios (ORs) of detection of anti-DFS70 using AC-2 after re-evaluation of total samples (OR 101.9, 95% CI 11.7–886.4, p-value < 0.001) and subgroup analysis of patients' samples (OR 53.8, 95% CI 5.9–493.6, p-value < 0.001). The OR of anti-nucleosome/histone/dsDNA detection using AC-1 in re-evaluated data increased to 5.43 (95% CI 1.00–29.61, p-value = 0.05). In the analysis of specific autoantibodies, more than half of the samples with an AC-2 pattern (54.2%) had specific autoantibodies other than anti-DFS70. We conclude that the flowchart for discriminating between AC-1 and AC-2 ANA patterns in this study is a viable practical guide for other laboratories when encountering equivocal ANA results. [ABSTRACT FROM AUTHOR]

Wireless sensor networks are highly constrained networks, specifically by their limited energy. In this paper, we proposed the Max Stable Protocol (MSP) to prolong their life as max as possible. MSP is a one-hop non-clustering protocol for homogeneous wireless sensor networks. These characteristics are proved mathematically in a detailed study of the LEACH energy model, mostly used to modulate wireless sensor network communication operations. Simulation results prove that our MSP reaches the network max possible stable period, lifetime, with max throughput level compared to FBECS, E-CAFL, and LEACH-FC protocols. MSP succeeded in extending the network stable period by 315.625, 315.625, 287.258 %, and the lifetime by 245.340, 237.277, and 232.475% with a very high throughput level against FBECS, E-CAFL, and LEACH-FC, respectively. [ABSTRACT FROM AUTHOR]

Abstract Background The initial phase of earthquake hazard assessment involves the consolidation of diverse magnitude scales, thereby requiring the homogenization of various magnitudes. Moment magnitude (Mw) emerges as the preferred descriptor for a range of magnitudes, encompassing local magnitude (ML), teleseismic magnitude (e.g., mb and MS), duration magnitudes (MD), and other magnitude proxies. Unlike alternative scales, Mw does not exhibit saturation at high magnitudes, enhancing its reliability. To achieve uniformity in magnitude representation, diverse regression techniques are employed, with the General Orthogonal Regression (GOR) method being widely regarded as the most dependable, accounting for uncertainty in both independent and dependent variables. Methods This study utilized the International Seismological Centre (ISC) Catalogue ( http://www.isc.ac.uk/ ) to compile an array of events related to the East Africa Rift System (EARS). Subsequently, the General Orthogonal Regression method was applied to merge and harmonize the collected data. Furthermore, the research computed Gutenberg-Richter b-values using the newly unified magnitude. Results Notably, the conversion relationships between magnitude proxies, including MS-mb, mb-Mw, MS-Mw, and ML-Mw, exhibited robust correlations, with coefficients of 0.86, 0.80, 0.88, and 0.94, respectively. In contrast, the relationship between ML and mb proxies revealed a notably weaker correlation, registering a coefficient of 0.54. Ultimately, the study identified a magnitude of completeness and a b-value of 3.8 and 0.71, respectively, for the EARS region, providing valuable insights for earthquake hazard assessment in this area. Conclusion Generally, the homogeneous catalogue is a step forward in seismicity assessment and geodynamic activities in the EARS. Hence, developing the empirical equations for the area is essential for future studies on seismic hazards and engineering applications due to the peculiarity of EARS’s geological and tectonic characteristics.

The escalating accumulation of plastic waste in landfills and marine environments has become a pressing concern to society. Among all plastic-based waste, polystyrenes are widely utilized as a commodity plastic and present very low recyclability. To improve this scenario, photocatalysis has recently become one of the viable techniques which can be performed under mild conditions. In this concise review, we have highlighted recent advancements in the valorization of polystyrene-based plastic waste by mainly focusing on the selective functionalization of the C–H bonds. This strategy clearly holds strong promise for the sustainable and efficient conversion of polystyrene-based waste and contributes to the reduction of waste and resource conservation.

Background: The initial phase of earthquake hazard assessment involves the consolidation of diverse magnitude scales, thereby requiring the homogenization of various magnitudes. Moment magnitude (Mw) emerges as the preferred descriptor for a range of magnitudes, encompassing local magnitude (ML), teleseismic magnitude (e.g., mb and MS), duration magnitudes (MD), and other magnitude proxies. Unlike alternative scales, Mw does not exhibit saturation at high magnitudes, enhancing its reliability. To achieve uniformity in magnitude representation, diverse regression techniques are employed, with the General Orthogonal Regression (GOR) method being widely regarded as the most dependable, accounting for uncertainty in both independent and dependent variables. Methods: This study utilized the International Seismological Centre (ISC) Catalogue (http://www.isc.ac.uk/) to compile an array of events related to the East Africa Rift System (EARS). Subsequently, the General Orthogonal Regression method was applied to merge and harmonize the collected data. Furthermore, the research computed Gutenberg-Richter b-values using the newly unified magnitude. Results: Notably, the conversion relationships between magnitude proxies, including MS-mb, mb-Mw, MS-Mw, and ML-Mw, exhibited robust correlations, with coefficients of 0.86, 0.80, 0.88, and 0.94, respectively. In contrast, the relationship between ML and mb proxies revealed a notably weaker correlation, registering a coefficient of 0.54. Ultimately, the study identified a magnitude of completeness and a b-value of 3.8 and 0.71, respectively, for the EARS region, providing valuable insights for earthquake hazard assessment in this area. Conclusion: Generally, the homogeneous catalogue is a step forward in seismicity assessment and geodynamic activities in the EARS. Hence, developing the empirical equations for the area is essential for future studies on seismic hazards and engineering applications due to the peculiarity of EARS's geological and tectonic characteristics. Article highlights: The empirical relations developed on the basis of the updated catalogue for the EARS are crucial and strong agreement with global studies for the earthquake hazard analysis in the region. The magnitude of completeness, Mc, for the EARS is significantly low as catalogues are continuously being updated. b-value obtained reveals that the EARS is experiencing active stress field with b-value significantly lower than 1. [ABSTRACT FROM AUTHOR]

Low reflectivity is of great significance to photoelectric devices, optical displays, solar cells, photocatalysis and other fields. In this paper, vanadium oxide is deposited on pattern SiO2 via atomic layer deposition and then annealed to characterize and analyze the anti-reflection effect. Scanning electron microscope (SEM) images indicate that the as-deposited VOx film has the advantages of uniformity and controllability. After annealing treatment, the VO2@pattern SiO2 has fewer crevices compared with VO2 on the accompanied planar SiO2 substrate. Raman results show that there is tiny homogeneous stress in the VO2 deposited on pattern SiO2, which dilutes the shrinkage behavior of the crystallization process. The optical reflection spectra indicate that the as-deposited VOx@pattern SiO2 has an anti-reflection effect due to the combined mechanism of the trapping effect and the effective medium theory. After annealing treatment, the weighted average reflectance diminished to 1.46% in the visible near-infrared wavelength range of 650–1355 nm, in which the absolute reflectance is less than 2%. Due to the multiple scattering effect caused by the tiny cracks generated through annealing, the anti-reflection effect of VO2@pattern SiO2 is superior to that of VOx@pattern SiO2. The ultra-low reflection frequency domain amounts to 705 nm, and the lowest absolute reflectance emerges at 1000 nm with an astonishing value of 0.86%. The prepared anti-reflective materials have significant application prospects in the field of intelligent optoelectronic devices due to the controllability of atomic layer deposition (ALD) and phase transition characteristics of VO2. [ABSTRACT FROM AUTHOR]

Rhodium as a national strategic reserve metal, has the irreplaceable role of other metals, but its resources are mainly concentrated in some countries in South Africa, and rhodium resources are very scarce in our country. In the process of industrialization in China, a large number of rhodium-containing homogeneous spent rhodium catalysts are produced, of which rhodium content is much higher than that of ores, so it is particularly important to recover rhodium from rhodium-containing homogeneous spent catalysts. By referring to the relevant literature, this paper summarized the recycling methods and prospected its prospects. [ABSTRACT FROM AUTHOR]

Water oxidation (WO) is the first step in the water-splitting process aiming at the production of hydrogen as a green renewable fuel. To successfully perform WO, potent strategies for overcoming the high energetic barrier and slow kinetics of this reaction are urgently required. One such strategy is the use of molecular catalysis. Specifically, Cu-based catalysts have been highlighted over the last decade due to their stability and fast kinetics. Among them, Cu-peptoids, where peptoids are peptidomimetics akin to peptides and are N-substituted glycine oligomers, can act as stable and active catalysts for oxidation transformations including electrocatalytic WO. Previously, we suggested that a benzyl group incorporated as a side chain near the catalytic site within a Cu-peptoid electrocatalyst for WO has a structural role in the activity of the electrocatalyst in phosphate buffer (PBS). Herein, we aimed to test this hypothesis and understand how an incorporated structural element side chain affects WO. To this aim, we prepared a set of peptoid trimers each with a different structural element replacing the benzyl group by either naphthyl, cyclohexyl, benzyl, propyl chloride, or propyl side chains as well as a peptoid lacking a structural element. We studied the structure of their Cu complexes and tested these complexes as electrocatalysts for WO. We discovered that while all the peptoids self-assemble to form dinuclear Cu-peptoid complexes, the duplex that has no structural side chain, Cu2(BE)2, is structurally different from the others in the solid state. Moreover, Cu2(BE)2 remains dinuclear in a PBS at pH 11, while all the other duplexes are mononuclear in the PBS. Finally, though most of the complexes showed low electrocatalytic activity for WO, the dinuclear complex Cu2(BE)2 performed with the highest turnover frequency of 484 s−1. Nevertheless, this dinuclear complex slowly decomposes to the corresponding mononuclear complex as a more stable species during WO, while the other mononuclear complexes retain their structure in solution but display much slower kinetics (ca. 5 to 8 s−1) under the same conditions. Overall, our results demonstrate that bulkier side chains hamper the stability of dinuclear Cu-peptoids in a PBS, and hence, their efficiency as WO electrocatalysts is also hampered. [ABSTRACT FROM AUTHOR]

A rapid and convenient homogeneous aptamer sensor with high sensitivity is highly desirable for the electrochemical detection of tumor biomarkers. In this work, a homogeneous electrochemical aptamer sensor is demonstrated based on a two-dimensional (2D) nanocomposite probe and nanochannel modified electrode, which can realize sensitive detection of carcinoembryonic antigen (CEA). Using π-π stacking and electrostatic interaction, CEA aptamer (Apt) and cationic redox probe (hexaammineruthenium(III), Ru(NH3)63+) are co-loaded on graphite oxide (GO), leading to a 2D nanocomposite probe (Ru(NH3)63+/Apt@GO). Vertically ordered mesoporous silica-nanochannel film (VMSF) is easily grown on the supporting indium tin oxide (ITO) electrode (VMSF/ITO) using the electrochemical assisted self-assembly (EASA) method within 10 s. The ultrasmall nanochannels of VMSF exhibits electrostatic enrichment towards Ru(NH3)63+ and size exclusion towards 2D material. When CEA is added in the Ru(NH3)63+/Apt@GO solution, DNA aptamer recognizes and binds to CEA and Ru(NH3)63+ releases to the solution, which can be enriched and detected by VMSF/ITO electrodes. Based on this mechanism, CEA can be an electrochemical detection ranging from 60 fg/mL to 100 ng/mL with a limit of detection (LOD) of 14 fg/mL. Detection of CEA in human serum is also realized. The constructed homogeneous detection system does not require the fixation of a recognitive aptamer on the electrode surface or magnetic separation before detection, demonstrating potential applications in rapid, convenient and sensitive electrochemical sensing of tumor biomarkers. [ABSTRACT FROM AUTHOR]

fac-Re(2,2'-bipyridine)(CO)3Cl] (denoted as ReCC) is an efficient molecule-catalyst with high selectivity in the photoreduction of CO2 to CO in a homogeneous system. However, the two major drawbacks of Re(I) complexes in the homogeneous system, easy degradation and difficult separation, seriously hinder its development in the field of industrial applications. In this paper, we designed and prepared two different Re-complex fixation systems (denoted as ReCC@TiO2-5 wt% and ReCC-TiO2-5 wt%) based on TiO2 gel via the sensitization method and sol–gel method, respectively. Compared with a pure ReCC complex, both of them exhibited excellent photocatalytic reduction activity. In particular, the sol–gel hybrid system (ReCC-TiO2-5 wt%) displayed outstanding positive synergistic effects on the photocatalytic activity and the long durability of the photocatalytic process. A series of characterizations were carried out to explore the probable photocatalytic reduction process mechanism, which provides the theoretical basis and technical support for the Re complex fixation method. [ABSTRACT FROM AUTHOR]

Abstract This study considers the problem of detecting range‐spread targets embedded in subspace interference plus Gaussian clutter with an unknown covariance matrix. The target and interference signals are modeled in terms of deterministic signals belonging to two known subspaces, respectively. Based on the Gradient test criterion, two adaptive detectors are devised for rejecting subspace interference in homogeneous and partially homogeneous environments, respectively. Both of the proposed detectors theoretically exhibit a desirable property of a constant false alarm rate with respect to the clutter covariance matrix as well as the power level. Furthermore, the numerical results show that, compared with their existing counterparts, the proposed detectors exhibit better detection performance and satisfactory suppression performance for the interference.

Based on Vygotsky's concept of Zone of Proximal Development, dynamic assessment (DA) has at its core the integration of assessment and instruction through mediation. DA is practiced either individually or collectively. In group-dynamic assessment (G-DA), as Poehner (2009) introduced, learners are simultaneously exposed to mediation. The problem which has been ignored in G-DA is the homogeneity and heterogeneity of EFL leaners while being mediated. This study tried to investigate the effect of group-dynamic assessment on homogeneous and heterogeneous EFL learners' ability in listening comprehension. It also intended to find out if expert-novice and peer-to-peer mediation types in G-DA differed in their effects on homogeneous and heterogeneous EFL learners' command of listening comprehension. To this end, eighty intermediate EFL learners were chosen to be the participants. According to their language proficiency, they were assigned to two groups of forty homogeneous and forty heterogeneous learners. Then, each group was divided into two experimental groups. The participants in all groups attended three listening sessions. For the mediation, the participants were assisted through novice-expert and peer-to-peer mediation types. To find out the main and interaction effect of group type and mediation type in G-DA, the post-test scores were analysed through running a two-way ANOVA. The results indicated that both group type and mediation type had significant main and interaction effect on learners' listening comprehension. A post hoc test was also utilized to compare the mean differences between the groups.

In this study, flaxseed oil body was taken as the research object, and stable flaxseed oil body emulsion rich in α-linolenic acid was obtained through homogenization treatment, which provides a new way for residents to increase the intake of ω-3 unsaturated fatty acids in daily diet. Under the same homogenous conditions (3 min) each time, changing the homogenization pressure (40, 80, 120 MPa) and the number of times (1~3 times) of flaxseed oil emulsions, the effects of homogenization on the properties, environmental stability ( pH, ionic strength, thermal, oxidation stability) and storage stability, and digestive properties of flaxseed oil emulsions were investigated. The results showed that the absolute value of potential zeta potential increased and the particle size decreased significantly when flaxseed oil body was homogenized at 120 MPa for three times (P0.05). The results of digestion showed that the homogenized flaxseed oil body emulsion had a higher release rate of fatty acids (FFA). In conclusion, the homogenization treatment significantly reduced the particle size of flaxseed oil emulsion, enhanced the storage stability and oxidation stability of flaxseed oil body, and accelerated the release rate of fatty acid.

Facial expression recognition (FER) plays a crucial role in understanding human emotions and is becoming increasingly relevant in educational contexts, where personalized and empathetic interactions are essential. The problems with existing approaches are typically solved using a single deep learning method, which is not robust with complex datasets, such as FER data, which have a characteristic imbalance and multi-class labels. In this research paper, an innovative approach to FER using a homogeneous ensemble convolutional neural network, called HoE-CNN, is presented for future online learning education. This paper aims to transfer the knowledge of models and FER classification using ensembled homogeneous conventional neural network architectures. FER is challenging to research because there are many real-world applications to consider, such as adaptive user interfaces, games, education, and robot integration. HoE-CNN is used to improve the classification performance on an FER dataset, encompassing seven main multi-classes (Angry, Disgust, Fear, Happy, Sad, Surprise, Neutral). The experiment shows that the proposed framework, which uses an ensemble of deep learning models, performs better than a single deep learning model. In summary, the proposed model will increase the efficiency of FER classification results and solve FER2013 at a accuracy of 75.51%, addressing both imbalanced datasets and multi-class classification to transfer the application of the model to online learning applications.

The inverted Y-tail joint standoff weapon is adopted as the Subsonic Unpowered Gliding Vehicle (SUGV) in this article to gain maximum standoff distance. To obtain the optimal standoff distance of SUGV, a direct approach i.e., homogeneous control vector parameterization (CVP), is employed. To achieve the maximum standoff distance, the SUGV requires to spend a maximum amount of time in the air to conduct a gliding flight, resulting in an unspecified final time optimal problem. To deal with this problem, a time scaling approach is adopted in conjunction with homogeneous CVP to achieve the maximum standoff distance. In accordance with the homogeneous CVP technique, the standoff distance of the SUGV is comparatively long in comparison to the maximum step input, and the SUGV reaches a standoff distance of 121 km with an increment of 1.77%. The optimal simulation outcomes indicate that homogeneous CVP delivers a smooth gliding flight as compared to the maximum step input, and this smoother flight results in increased standoff distance. Furthermore, to evaluate the efficiency between the homogeneous CVP approach and maximum step input, the burden on the elevators in the form of integral square value and time scaling parameter is chosen as a criterion for quantitative analysis, and this analysis reveals that the homogeneous CVP approach has less burden on the elevators than the maximum step input.

Bioethanol is a major raw chemical produced in large quantities by the fermentation of sugar-containing crops and lignocellulosic materials. As a consequence, there is a need for advanced methods to convert ethanol into fine chemicals. Here, we report the synthesis of higher-order alcohols by cross-coupling of ethanol with primary alcohols under solvent-free conditions, catalyzed by low amounts of a selective manganese pincer complex under mild reaction conditions with a stoichiometric amount of sodium ethoxide. Poisoning experiments suggest that the catalysis system is homogeneous. [ABSTRACT FROM AUTHOR]

The third real de Rham cohomology of compact homogeneous spaces is studied. Given M = G / K with G compact semisimple, we first show that each bi-invariant symmetric bilinear form Q on g such that Q | k × k = 0 naturally defines a G-invariant closed 3-form H Q on M, which plays the role of the so called Cartan 3-form Q ([ · , · ] , ·) on the compact Lie group G. Indeed, every class in H 3 (G / K) has a unique representative H Q . Second, focusing on the class of homogeneous spaces with the richest third cohomology (other than Lie groups), i.e., b 3 (G / K) = s - 1 if G has s simple factors, we give the conditions to be fulfilled by Q and a given G-invariant metric g in order for H Q to be g-harmonic, in terms of algebraic invariants of G/K. As an application, we obtain that any 3-form H Q is harmonic with respect to the standard metric, although for any other normal metric, there is only one H Q up to scaling which is harmonic. Furthermore, among a suitable (2 s - 1) -parameter family of G-invariant metrics, we prove that the same behavior occurs if k is abelian: either every H Q is g-harmonic (this family of metrics depends on s parameters) or there is a unique g-harmonic 3-form H Q (up to scaling). In the case when k is not abelian, the special metrics for which every H Q is g-harmonic depend on 3 parameters. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of initial conditions characterized by compressibility of turbulence on the changes in scalar such as density, temperature, and pressure within the framework of rapid distortion theory (RDT) in the case of non-isentropic turbulence. This study is a follow-up of the basic work carried out by A. Simone, G.N. Coleman and C. Cambon [J. Fluid Mech. 330, 307 (1997)] in the case of quasi-isentropic turbulence and the previous work of M. Riahi and T. Lili [Fluid Dyn. Res. 52, 025501 (2020)] in the case of non-isentropic turbulence. RDT was used to examine the behavior of the root mean square (rms) fluctuations of density, temperature, and pressure. The coupling between these rms quantities, the partition factor, and the polytropic coefficient was also studied. RDT equations were solved numerically using a code that solves directly evolution equations of two-point spectral correlations for compressible homogeneous sheared non-isentropic turbulence. The RDT analysis was carried out for various initial turbulent Mach numbers Mt0 ranging from 0.1 to 0.4, and the initial compressible turbulence is to be one of the three states concerning the fraction of kinetic energy χ0: solenoidal (χ0 = 0), mixed (χ0 = 0.6), and dilatational (χ0 = 1) (χ0 is the ratio of the initial dilatational kinetic energy to the initial total kinetic energy). It is shown from this study that the changes in scalars are strongly dependent on the initial conditions. Magnitudes and asymptotic values of rms thermodynamics fluctuations and correlations between these thermodynamics fluctuations depend of Mt0. For large times, the isentropic state of the flow is well observed whatever Mt0 and χ0. [ABSTRACT FROM AUTHOR]

Reductive amination is a valuable method for amine synthesis that has been the topic of a century's worth of in‐depth study in both academia and industry. Amines and their derivatives serve as incredibly adaptable building blocks for a broad array of organic substrates and are significant precursors for a myriad of advanced chemicals, physiologically active compounds, agrochemicals, biomolecules, pharmaceuticals, and polymers. The creation of innovative catalytic processes for the long‐term and selective synthesis of amines from readily accessible and environmentally benign reagents remains a top priority in chemical research. Both heterogeneous and homogeneous catalysts have been designed with success to enable these reactions to explore new amines. Ruthenium catalysts are employed in reductive amination owing to their stability, selectivity, versatility, low toxicity, and high efficiency. This review comprehensively overviews the Ru‐catalyzed reductive amination processes and includes the literature from 2009 to 2022. [ABSTRACT FROM AUTHOR]

This paper discusses the development of two different bi-phase flows. Fourth-grade fluid exhibiting the non-Newtonian fluid nature is taken as the base liquid. Two-phase suspension is obtained by using the spherically homogeneous metallic particle. Owing to the intense application of mechanical and chemical multiphase flows through curved and bent configurations effectively transforms the flow dynamics of the fluid. Differential equations for electro-osmotically driven fluid are modeled and solved with the help of the regular perturbation method. The obtained theoretical solution is further compared with the ones obtained by using two different numerical techniques and found to be in full agreement. [ABSTRACT FROM AUTHOR]

This paper studies the evolution of opinions over random social networks subject to individual biases. An agent reviews the opinion of a randomly selected one and then updates its opinion under homogeneous biased assimilation. This study investigates the impact of biased assimilation on random opinion networks, which is different from the previous studies on fixed network structures. If the bias parameters are static, it is proven that the event in which all agents converge to extreme opinions happens almost surely. Next, the opinion polarization event is proved to be a probability one event. While if the bias parameters are dynamic, the opinion evolution is proven to depend on early finite time slots for the dynamical individual bias parameter functions independent of the biased parameter values after the time threshold. Numerical simulations further show that opinion evolution depends on early finite time slots for some nonlinear dynamical individual bias parameter functions. [ABSTRACT FROM AUTHOR]

With the rapid development of industry and the increasing demand for transportation, traditional sources of energy have been excessively consumed. Biodiesel as an alternative energy source has become a research focus. The most common method for biodiesel production is transesterification, in which lipid and low carbon alcohol are commonly used as raw materials, in the presence of a catalyst. In the process of transesterification, the performance of the catalyst is the key factor of the biodiesel yield. This paper reviews the recent research progress on homogeneous and heterogeneous catalysts in biodiesel production. The advantages and disadvantages of current homogeneous acid catalysts and homogeneous base catalysts are discussed, and heteropolyacid heterogeneous catalysts and biomass-derived base catalysts are described. The applications of the homogeneous and heterogeneous catalyst derivatives ionic liquids/deep eutectic solvents and nanocatalysts/magnetic catalysts in biodiesel production are reviewed. The mechanism and economic cost of current homogeneous acid catalysts and homogeneous base catalysts are also analyzed. The unique advantages of each type of catalyst are compared to better understand the microscopic details behind biodiesel. Finally, some challenges of current biodiesel catalysts are summarized, and future research directions are presented. This review will provide general and in-depth knowledge on the achievements, directions, and research priorities in developing novel homogeneous/heterogeneous catalysts for the green and cost-effective production of biodiesel. [ABSTRACT FROM AUTHOR]

To obtain homogeneous submicron cerium dioxide (CeO2) polishing powder, CeO2 was synthesized by solvothermal reaction using cerium nitrate (Ce(NO3)3·6H2O) as cerium resource and alcohol-water mixed solution as solvent. The phase composition and morphology of CeO2 were characterized by X-ray diffraction (XRD), laser particle size analyzer and scanning electron microscope (SEM). The formation process of CeO2 particles was analyzed by changing the concentration of Ce3+ and alcohol-water ratio. The synthesized CeO2 was used for chemical mechanical polishing (CMP) Si-face of 6H-SiC. The polishing characteristics were tracked by atomic force microscopy (AFM) and electronic balance. The results indicates that when the Ce3+ concentration is 0.10 mol/L and alcohol/water volume ratio is 3∶1, the as-prepared particles have regular morphology, moderate particle size and uniform particle size distribution. After polished by using the as-prepared CeO2, the Ra of wafer surface reached 0.243 nm and the dMRR 287 nm/h. The as-prepared CeO2 can be used for chemical mechanical polishing.

In this work, the ability of a Reynolds stress model to compute turbulent homogeneous shear flow with significant compressibility effects is discussed. Several studies of compressible turbulent flows carried out in the past years have shown that the pressure strain correlation is mainly responsible for the strong changes in the magnitude of the Reynolds stress anisotropies. Two recent compressible models of this term are considered in conjunction with the standard model of the dissipation rate of the turbulent kinetic energy to predict compressible homogeneous flow highly sheared are tested. It is found that deficiencies appear in the calculations even if the pressure strain model is improved by compressibility corrections. Consistent with earlier studies, this deficiency is attributed to the use of the incompressible model for turbulent dissipation. However, a compressibility correction of this equation model uncovers the main focus of the present study. This correction makes the standard coefficients of this equation depend on the turbulent gradient Mach and Mach numbers. The proposed model is tested for low and strong compressibility cases from the DNS results of Sarkar. A comparison of the proposed model predictions with the DNS results shows good qualitative agreement. Therefore, compressibility correction for the incompressible model of the turbulent dissipation rate is found to be an important issue for the compressible homogeneous turbulent shear flow. [ABSTRACT FROM AUTHOR]

This study considers the problem of detecting range‐spread targets embedded in subspace interference plus Gaussian clutter with an unknown covariance matrix. The target and interference signals are modeled in terms of deterministic signals belonging to two known subspaces, respectively. Based on the Gradient test criterion, two adaptive detectors are devised for rejecting subspace interference in homogeneous and partially homogeneous environments, respectively. Both of the proposed detectors theoretically exhibit a desirable property of a constant false alarm rate with respect to the clutter covariance matrix as well as the power level. Furthermore, the numerical results show that, compared with their existing counterparts, the proposed detectors exhibit better detection performance and satisfactory suppression performance for the interference. [ABSTRACT FROM AUTHOR]

The amide functional group is ubiquitous in living organisms, and is of particular importance in bioactive compounds and pharmaceuticals. Because of the prevalence and significance of the amide bond, considerable efforts have been invested throughout the years in developing new synthetic methodologies for its formation. Nevertheless, amide synthesis still largely relies on variants of the traditional condensation of carboxylic acids and amines, mediated by stoichiometric coupling reagents. This poses a sustainability challenge, since such reactions suffer from unfavorable atom and step economies, involve harmful chemicals and produce chemical waste. Hence, establishing sustainable approaches to amide synthesis is of great importance. Over the last two decades, we have developed homogeneous catalytic reactions for sustainable synthetic transformations, primarily based on transition metal complexes of pincer ligands. A considerable portion of these efforts has been devoted to acceptorless dehydrogenative coupling, including that of alcohols and amines through ruthenium-catalyzed reactions. These latter processes generate amides without resorting to coupling reagents and typically produce no waste, with their only byproduct being H2 gas, which is itself a valuable resource. In the present review, we chronicle our progress in this area of research since 2014. This includes the use of water and ammonia as amidation reagents, expanding the scope of amidation substrates and target amides, achieving milder reaction conditions, development of amidation-based liquid organic hydrogen carrier systems, and introduction of manganese-based catalysts. [ABSTRACT FROM AUTHOR]

Determining the amount of void fraction of multiphase flows in pipelines of the oil, chemical and petrochemical industries is one of the most important challenges. Performance of capacitance based two phase flow meters highly depends on the fluid properties. Fluctuation of the liquid phase properties such as density, due to temperature and pressure changes, would cause massive errors in determination of the void fraction. A common approach to fix this problem is periodic recalibration of the system, which is a tedious task. The aim of this study is proposing a method based on artificial intelligence (AI), which offers the advantage of intelligent measuring of the void fraction regardless of the liquid phase changes without the need for recalibration. To train AI, a data set for different liquid phases is required. Although it is possible to obtain the required data from experiments, it is time-consuming and also incorporates its own specific safety laboratory consideration, particularly working with flammable liquids such as gasoline, oil and gasoil. So, COMSOL Multiphysics software was used to model a homogenous regime of two-phase flow with five different liquid phases and void fractions. To validate the simulation geometry, initially an experimental setup including a concave sensor to measure the capacitance by LCR meter for the case that water used as the liquid phase, was established. After validation of the simulated geometry for concave sensor, a ring sensor was also simulated to investigate the best sensor type. It was found that the concave type has a better sensitivity. Therefore, the concave type was used to measure the capacitance for different liquid phases and void fractions inside the pipe. Finally, simulated data were used to train a Multi-Layer Perceptron (MLP) neural network model in MATLAB software. The trained MLP model was able to predict the void fraction independent of the liquid phase density changes with a Mean Absolute Error (MAE) of 1.74. [ABSTRACT FROM AUTHOR]

Although widely used numerical models can assess the stability of lateral hinges in high tibial osteotomy (HTO) and may provide acceptable results in comparative studies, accurate stress prediction may not be possible due to simplified homogeneous models of the bone. The present study aimed to investigate the effect of a heterogeneous versus four homogeneous models on the results of stress and force. Each of the four homogenized FE models utilized the same elastic modulus of 16,700 MPa for the cortical while employing a single elastic modulus varying from 155 to 5000 MPa for the cancellous. In heterogeneous model, the modulus of each element was assigned using the bone density. It was found that stresses at the hinge in homogeneous models were higher than those in the heterogeneous model. The maximum principal stress (MPS) was 437 MPa for the heterogeneous model while that was 2179, 2351, 2581, and 2637 MPa for the homogeneous models with the elastic moduli of 155, 500, 2130, and 5000 MPa, respectively. Also, the opening force was 150 N for the heterogeneous model significantly lower than 649–1534 N range predicted for the homogeneous models. The use of a homogeneous model in the FE analysis of HTO overestimated the stresses and force. Thus, in addition to casting doubt on the use of a single modulus in the numerical analysis of HTO, Future HTO studies can use our results as a benchmark for comparison purposes and highlight the use of patient-specific bone density – elastic modulus relation in simulation. [ABSTRACT FROM AUTHOR]

Carbonaceous surface, as one of the major carriers in coal combustion, was found to exert great influence on the nitric oxide with carbon monoxide (NO–CO) reaction. Although there have been some studies addressing the NO–CO reaction, the inherent mechanism remains obscure. In this work, some updated mechanisms with details were proposed at the electronic level. Using density functional theory calculations, the preferred pathways were identified with three channels consisting of homogeneous, Eley–Rideal (E-R), and Langmuir–Hinshelwood (L–H) heterogeneous reactions. The reasons for the difference in energy barrier among the three mechanisms were revealed by analyzing the chemical bond and electronic transfer. Results show that among these channels, the NO–CO reaction is more likely to occur along the E-R mechanism, due to its lower energy barrier of the rate-determining step. Compared to the L–H mechanism, there is a higher degree of electronic localization between NO molecules at the initial stage of the E-R mechanism. As a result, the NO dimer formation of the E-R mechanism has a lower energy barrier than that of the L–H mechanism. Meanwhile, a large number of electrons floods into the N–N, N–O, and O–O bonds of NO dimer in the homogeneous reaction, which certainly gets more difficult for the dissociation of O atoms in the gas phase. Accordingly, the following stage of N2 formation in the homogeneous reaction has a higher energy barrier than that in both the E-R and L–H reactions. Compared to the L–H mechanism, the E-R mechanism exhibits a lower degree of electronic localization between N2O and carbonaceous surface, suggesting that the interfacial interaction in the E-R mechanism is weaker. As a result, N2 is easier to remove from the carbonaceous surface in the E-R mechanism than in the L–H mechanism. To sum up, the results deepen the knowledge about the NO–CO reaction, which will help to further develop the oxy-fuel combustion technology. [ABSTRACT FROM AUTHOR]

The Liutex vector is new quantity introduced to represent the rigid-body rotation part of fluid motion and thus to define and identify vortices in various flows. In this work, the intermittency and power-law similarity of the Liutex vector in homogeneous, isotropic turbulence and a turbulent channel are explored. First, we found that the Liutex vector is more intermittent than the vorticity vector in the considered turbulent flows, which indicates that an iso-surface of a Liutex magnitude with an appropriate threshold could capture the major rotating motions or vortical motions of the flow. Second, the three-dimensional energy spectrums of velocity, vorticity (enstrophy spectrum) and the Liutex vector in homogeneous isotropic turbulence are shown to exhibit power laws of −5/3, 1/3 and 1/3 in the inertial subrange, respectively, whilst the Liutex energy spectrum particularly satisfies an additional −10/3 power law in the viscous subrange. This viscous similarity of the Liutex vector is the only power law that survived from the wall presence and is argued to originate from the fact that the Liutex vector represents the rigid part of fluid motion and is free from any shear contamination. The existence of such a viscous similarity law indicates a certain coherence of the small scales of turbulence and could possibly help understand and model turbulence. [ABSTRACT FROM AUTHOR]