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This 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]

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]

Comprehensive Summary The present work prepared a copper N‐heterocyclic carbene complex that could be used in catalyzing the homogeneous hydrogenation of carboxylic acid with ammonia borane (hydrogen source) to synthesize primary alcohols. Various aromatic and aliphatic carboxylic acids with diverse functional groups were transformed to respective alcohols in moderate to high yields. The process can be easily scaled up (TON up to 14545) and exhibits a high compatibility with different sensitive functional groups, including fluorine, chlorine, bromine, iodine, hydroxyl, cyano and nitro groups. IMesCuCl/NH3·BH3 combination can selectively reduce aromatic and aliphatic esters. Mechanistic studies indicate that Cu‐H species produced in situ are the active intermediates. [ABSTRACT FROM AUTHOR]

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 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]

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]

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]

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]

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]

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]

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]

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]

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]

Currently, although >10 antibody−drug conjugates (ADCs) are available in the market, most of them (10 ADCs) have broad drug distribution, thereby potentially limiting their therapeutic index. The ADC industry is shifting from random conjugation technology to site‐specific conjugation technology to overcome this issue. Enzymatic site‐specific conjugation is a promising cutting‐edge technology owing to its mild conjugation conditions. This review discussed enzymatic conjugation strategies for producing ADCs via modifying native antibodies without using a tag moiety. We described the comparison of the three main conjugation technologies used to produce site‐specific ADCs. Each of the three enzymatic approaches described in this review differs in their advantages and disadvantages, providing pharmaceutical companies the option to select an approach suitable to their purpose and/or target protein. [ABSTRACT FROM AUTHOR]

Multicomponent reactions have received a lot of attention as a potential method for the synthesis of a wide range of complex organic molecules. Rapid development is being made in this field because of its importance in the chemical, pharmaceutical, biological, and industrial areas. Nickel is a versatile catalyst that can be used in a variety of synthetic transformations. In this review, we discuss the advancements in the field of Nickel‐catalyzed multicomponent reactions, covering the literature up to 2021. [ABSTRACT FROM AUTHOR]

The KdV equation has special significance as it describes various physical phenomena. In this paper, we use two methods, namely, a variational homotopy perturbation method and a classical finite-difference method, to solve 1D and 2D KdV equations with homogeneous and non-homogeneous source terms by considering five numerical experiments with initial and boundary conditions. The variational homotopy perturbation method is a semi-analytic technique for handling linear as well as non-linear problems. We derive classical finite difference methods to solve the five numerical experiments. We compare the performance of the two classes of methods for these numerical experiments by computing absolute and relative errors at some spatial nodes for short, medium and long time propagation. The logarithm of maximum error vs. time from the numerical methods is also obtained for the experiments undertaken. The stability and consistency of the finite difference scheme is obtained. To the best of our knowledge, a comparison between the variational homotopy perturbation method and the classical finite difference method to solve these five numerical experiments has not been undertaken before. The ideal extension of this work would be an application of the employed methods for fractional and stochastic KdV type equations and their variants. [ABSTRACT FROM AUTHOR]

This work presents a flat‐gain antipodal Vivaldi antenna (AVA) for ultra‐wideband (UWB) microwave imaging applications. The proposed antenna demonstrates measured and simulated impedance bandwidth from 2.3 GHz to 20 GHz with a flat gain over the band, with minimum gain variation of 2.9 dBi. The antenna is tested initially for its practical utility by measuring its specific absorption rate (SAR) value. The SAR value is observed in the simulator by modeling a realistic homogeneous as well as a heterogeneous breast phantom. The SAR value obtained complies with both American and European standards when averaged over 1 g as well as 10 g of tissue. The designed antenna is further utilized to detect multiple tumors in a realistic homogeneous and heterogeneous breast phantoms developed in the laboratory environment. The widely popular delay and sum (DAS) algorithm is utilized to reconstruct the tumor images. The imaging is done outside the anechoic chamber with an in‐house monostatic microwave imaging setup just to make it more convincing with real‐world dynamic scenario. The homogeneous phantom with four embedded tumors each of radius 4 mm and the heterogeneous phantom with two tumors, one of radius 3.5 mm and another of radius 5 mm are imaged in this work. The imaging results demonstrate that tumors of different sizes can be detected accurately in the case of both homogeneous and heterogeneous breast phantoms. AVA with an oil paper layer for bandwidth enhancement as well for achieving flat‐gain response is first of its kind to be reported in this work Also, the proposed work utilizes different phantoms for imaging several tumors of differing sizes, which has not before been described. [ABSTRACT FROM AUTHOR]

Non-homogeneous hydrolysis extent was able to be accurately described by a product of logistic with exponential convex growth function because of slow collision-complex formation between activated H 2 O and HD molecule to non-linearly couple with transition state decay according to Chain Reaction and Transition State theory, while the homogeneous has grown up only in an exponential convex function because of fast collision-complex formation to make its initial extent ratio extremely quickly close to unity. [Display omitted] • Extent equations for hydrolysis of Sulfur mustard are newly proposed. • An exponential convex growth function for homogeneous hydrolysis extent. • Its product with a logistic growth function for non-homogeneous hydrolysis extent. • Their rate constants strongly depend on initial and boundary conditions. • They are limited by the internal quantum state number of bi-molecular structure. This paper aims to establish a hydrolysis extent equation and rate dependence of initial and boundary conditions for sulfur mustard (HD) non-dissolved and dissolved in water by the following work. Firstly, non-homogeneous hydrolysis extent was found to be accurately described by a product of logistic with exponential convex growth function because of slow collision-complex formation between activated H 2 O and HD molecule to non-linearly couple with transition state decay, while the homogeneous has grown up only in an exponential convex function because of fast collision-complex formation to make its initial extent ratio extremely quickly close to unity. Secondly, initial non-temperature effects from (ethanol, acid, base) additives, HD concentration and droplet size, and rotation speed on hydrolysis rate could be summarized into a Boltzmann function of rate constant with initial molar free energy because of a thermal equilibrium distribution of internal quantum state at a given energy for bi-molecular structures before and after complexing. The results from 5 mL solution under vortex was nearly similar to the stirring 100 mL solution and would helpfully clarify the detoxification kinetics to establish a standard method for evaluating reactivity of aqueous decontaminants against chemical warfare agents at necessarily specified conditions. [ABSTRACT FROM AUTHOR]

All spaces are assumed to be separable and metrizable. Building on work of van Engelen, Harrington, Michalewski and Ostrovsky, we obtain the following results: • Every finite-dimensional analytic space is σ -homogeneous with analytic witnesses, • Every finite-dimensional analytic space is σ -homogeneous with pairwise disjoint Δ 2 1 witnesses. Furthermore, the complexity of the witnesses is optimal in both of the above results. This answers a question of Medini and Vidnyánszky, and completes the picture regarding σ -homogeneity in the finite-dimensional realm. It is an open problem whether every analytic space is σ -homogeneous. We also investigate finite unions of homogeneous spaces. [ABSTRACT FROM AUTHOR]

Low-loss and high-reflection mirrors have important applications in high-power laser systems. Conventional mirrors based on multilayer films are damaged by thermal distortion between the layers when irradiated by high-power lasers. In 2022, H. Atikian et al. designed and demonstrated a dielectric metasurface mirror for high-power continuous-wave lasers with a bandwidth of 10 nm and a reflectance of 98.9 ± 0.3% by etching nanostructures into the surface of single-crystal diamond to overcome the limitation of coating defects. We optimize the structure to achieve a broadband high reflection of 100 nm with 99.88% average reflectance. Furthermore, we extend the structure to other typical optical materials to achieve high reflection, such as silicon, alumina, and silicon oxide and find that relatively high refractive index is important to realize broadband high reflection. Our work provides a reference for the design of homogeneous material-based metasurface mirrors operating under high power conditions. • Metasurface mirrors have important applications in high-power laser systems. • A diamond metasurface mirror with 99.88% reflectance of 100 nm bandwidth is realized. • Metasurface mirrors with Si, Al 2 O 3 , and SiO 2 are also studied. [ABSTRACT FROM AUTHOR]

The objective of this experimental study was to find out if hybrid cellular beams subjected to bending would lead to increased strength and resistance when compared to their homogeneous counterpart sections. Cellular beams were subjected to mid-span concentrated load to study their load-carrying capacity, failure modes, and load versus vertical and lateral displacements behavior. IPE 330 and IPE 360 hot-rolled parent sections were used to fabricate eight cellular beams in three groups. Groups 1 and 2, each contain two homogeneous and hybrid sections, while group 3 contains two hybrid cellular beams. Steel grades of S275 and S355 were used for the homogeneous sections, while for hybrid sections, both S355 and S275 were used for the upper and lower Tee parts, respectively. The results of group 2 indicate that the use of hybrid cellular beams can be more efficient in terms of load-carrying capacity when compared to homogeneous cellular beams. However, results showed that the failure mechanism and load-carrying capacity of cellular beams were mainly governed by the upper Tee part and section class. Hence, in some cases, it was observed that the use of a higher steel grade affected the failure mechanism and thus degraded the resistance capacity of the section due to section classification effects. [ABSTRACT FROM AUTHOR]

Silica‐supported Pd, Rh and Pt metal nanoparticles catalyze the hydrogenolysis of the Pt−OPh bond of (tbpy)Pt(OPh)Cl to release PhOH. Based on kinetic studies monitored by 1H NMR spectroscopy, the reactivity trend is Pd>Rh>Pt. Kinetic studies with Pd/SiO2 are consistent with a first‐order dependence on the catalyst and the molecular Pt(II) complex (tbpy)Pt(OPh)Cl. Using TEM‐EDS mapping and ICP‐OES measurements of a recovered Pd catalyst, after 1 hour of hydrogenolysis of (tbpy)Pt(OPh)Cl, approximately 10–16 % Pt deposition (relative to Pd mol %) on the Pd/SiO2 surface was quantified. [ABSTRACT FROM AUTHOR]

Instabilities of thin wetting films show different dewetting dynamics when supported by different solid substrates. Unstable thin films on the homogeneous substrate are studied numerically and experimentally. This study extended to slipping films and density varying films analysing the variation in time of rupture and power-law exponents. However, none of the films are reported to produce smaller length scale patterns. One possible way to produce a smaller length scale pattern is by the heterogeneous substrate. A recent study confirms that thickness-dependent viscosity films on a homogeneous substrate produce smaller length scales due to the formation of a secondary set of satellite holes. Nevertheless, these films exhibit low power-law exponents compared to constant viscosity films and slipping films. Thin liquid films supported by a solid coated substrate, where film subjected to purely Lifshitz Van der Waals force describes the morphological phase separation and it reveals that the mechanism is different from classical nucleation. [ABSTRACT FROM AUTHOR]

We introduce a new variant of Chubanov's method for solving linear homogeneous systems with positive variables. In the Basic Procedure we use a recently introduced cut in combination with Nemirovski's Mirror-Prox method. We show that the cut requires at most O (n 3) time, just as Chubanov's cut. In an earlier paper it was shown that the new cuts are at least as sharp as those of Chubanov. Our Modified Main Algorithm is in essence the same as Chubanov's Main Algorithm, except that it uses the new Basic Procedure as a subroutine. The new method has O (n 3.5 log 2 ⁡ (1 / δ A)) time complexity, where δ A is a suitably defined condition number. As we show, a simplified version of the new Basic Procedure competes well with the Smooth Perceptron Scheme of Peña and Soheili and, when combined with Rescaling, also with two commercial codes for linear optimization. [ABSTRACT FROM AUTHOR]

Selective cleavage of C–C bonds forms one of the greatest challenges in current organic chemistry, due to the relative strength of these bonds. However, such transformations are an invaluable instrument to break down and construct new carbon–carbon bonds. To achieve this, photochemistry can be used as a tool to generate radicals and induce the cleavage of these bonds due to their high reactivity. This review examines some of the most influential contributions in this field since 2010. 1 Introduction 2 C–C Bond Cleavage 2.1 Homogeneous Catalyst 2.1.1 N-Centered Radical 2.2.2 O-Centered Radical 2.2 Heterogeneous Catalyst 3 C=C Bond Cleavage 3.1 Homogeneous Catalyst 3.2 Heterogeneous Catalyst 4 C≡C Bond Cleavage 4.1 Homogeneous Catalyst 4.2 Heterogeneous Catalyst 5 Conclusion [ABSTRACT FROM AUTHOR]

Light‐driven homogeneous and heterogeneous catalysis require a complex interplay between light absorption, charge separation, charge transfer, and catalytic turnover. Optical and irradiation parameters as well as reaction engineering aspects play major roles in controlling catalytic performance. This multitude of factors makes it difficult to objectively compare light‐driven catalysts and provide an unbiased performance assessment. This Scientific Perspective highlights the importance of collecting and reporting experimental data in homogeneous and heterogeneous light‐driven catalysis. A critical analysis of the benefits and limitations of the commonly used experimental indicators is provided. Data collection and reporting according to FAIR principles is discussed in the context of future automated data analysis. The authors propose a minimum dataset as a basis for unified collecting and reporting of experimental data in homogeneous and heterogeneous light‐driven catalysis. The community is encouraged to support the future development of this parameter list through an open online repository. [ABSTRACT FROM AUTHOR]

A novel oxo–peroxo tungsten(VI) Schiff base complex, [WO(O2)L(CH3OH)], as a homogeneous catalyst for sulfoxidation was synthesized by treating WO3 in H2O2 with an ONO–tridentate Schiff base ligand. The complex was characterized by FT-IR, UV–Vis, 1H NMR and 13C{1H} NMR spectroscopy. Moreover, the structure of the crystalline tungsten(VI) complex was further investigated by SC-XRD. The crystal structure analysis revealed that the coordination environment of the W complex is seven-coordinate, occupied by ONO sets of the coordinated ligand in a distorted pentagonal–bipyramidal. Also, the immobilized W(VI) Schiff base on chloromethylated polystyrene, showed high efficiency in the oxidation of the sulfide under heterogeneous conditions. The heterogeneous catalyst was systematically characterized by FT-IR, diffuse reflectance UV–Vis, XRD, FE-SEM, EDX, and ICP–AES techniques. Comparatively, the immobilized heterogeneous catalyst showed superior activity over its homogeneous counterpart and was reused several times. [ABSTRACT FROM AUTHOR]

Vanadium substituted Molybdotungstophosphoric acid (H5PW6Mo4V2O40·14H2O) was observed to be an effective solid catalyst for one-pot synthesis of several quinoxaline derivatives from the condensation reaction between various substituted o-phenylenediamine and various aromatic benzil compounds in ethanol: water (1:1) solvent under the reflux condition. The catalytic activity was tested under different reaction conditions to know the performance of the synthesized catalysts. Excellent yield, short reaction time, simple workup procedure, and reusability of the catalyst are the prominent features of our synthetic route. We report a series of vanadium substituted molybdotungstophosphoric acid, H5[PW6Mo4V2O40]·14H2O as a catalyst for the synthesis of quinoxaline derivatives. [ABSTRACT FROM AUTHOR]

We report herein the synthesis and application of enantiopure C2‐symmetric primary amine‐1,3‐bis‐thiourea organocatalysts in enantioselective conjugate 1,4‐Michael addition of carbonyl containing nucleophiles, to nitroalkenes and N‐phenylmaleimide, leading to final products in good enantioselectivities (up to 99%) and yields (up to 99%). We propose supramolecular noncovalent interactions within the organocatalyst's cleft between the substrate and the catalyst, via hydrogen bonding. Supramolecular interaction thus lowers the transition state energy mimicking an enzyme. Mechanism underlying our experimental results is supported by theorical calculations. [ABSTRACT FROM AUTHOR]

Various methods for activating peroxydisulfate to remove organic pollutants in aqueous solution over iron-based catalysts were reviewed. The key factors and their related mechanisms were respectively introduced in homogeneous and heterogeneous reactive systems, and their advantages and disadvantages were commented. It offered an important reference for the development of a novel and effective iron-based catalysts. [ABSTRACT FROM AUTHOR]

In this work, a homogeneous sensing platform was constructed for ultrasensitive electrochemical organophosphate pesticides (OPs) detection based on nano-enzyme NiCoFeS/rGO with high peroxidase-like activity. In the presence of H 2 O 2 , NiCoFeS/rGO catalyst oxidized o-phenylenediamine (OPD) to produce yellow OPDox with strong absorbance and reduction peak current. This activity could be inhibited by thiocholine (TCh) produced by acetylcholinesterase (AChE). However, presence of organophosphates (OPs) could inhibit AChE and reduce TCh production, enabling protect the peroxidase-like activity of NiCoFeS/rGO. So, according to the increased signal of OPDox, the content of OPs could be measured by colorimetric or electrochemical mode. Using electrochemical analysis mode and optimizing experimental conditions, the detection limit was low (9.74fg mL−1) and the linear range was wide (12.5fg mL−1-1.25 ng mL−1). The selectivity, stability reproducibility and practicability of the method were investigated. At the same time, the analysis results of colorimetric and electrochemical method for AChE and colorimetric method for OPs were preliminarily determined, respectively. • NiCoFeS/rGO with high peroxidase-like activity was synthesized by one-step hydrothermal method. • In situ generated Oxidized OPD can provide both colorimetric and electrochemical signals. • The homogeneous sensing system can be used to measure AChE and OPs by colorimetric or electrochemical method. • The ultrasensitive electrochemical detection of OPs was realized. • The practicability of the method was verified by using different kinds of fruits and vegetables. [ABSTRACT FROM AUTHOR]

Calcium alginate hydrogel/polyethersulfone (CaAlg/PES) hybrid membranes were synthesized via combining in situ ion crosslinking with phase conversion method. Once the Sodium alginate (NaAlg) uniformly dispersed in the casting solution contacted with Ca2+ dissolved in coagulation bath solution in the phase conversion membrane formation process, nanoscale CaAlg hydrogel was in situ formed through ion exchange and evenly dispersed in the membrane matrix. FT-IR and XPS were adopted to confirm the formation of CaAlg hydrogel distributed in PES membrane matrix. SEM, AFM, BET analysis and contact Angle analyzer were all used to characterize the surface changes of morphology, roughness and hydrophilicity in detail. Specific separation performance was also evaluated and compared by cross-flow ultrafiltration tests. Comprehensive analysis of the measured properties of all obtained membranes, when the content of NaAlg was 1.5 wt%, the CaAlg/PES hydrogel membrane M 32 had the most excellent performance. The pure water flux increased from 1967 to 2193 L/m2hMPa, rejection rate of BSA was up to 99.87 %, and RFR value was almost 76.83 % after 4 cycles BSA filtration. XPS characterization of the membrane after filtration for 72 hours showed that the retention rate of Ca (2 P) reached 95 %, which further proved the stability of the membrane operation. [Display omitted] [ABSTRACT FROM AUTHOR]

Considering the high probability of recurrence or metastasis after thyroidectomy, it is meaningful to develop a rapid, sensitive and specific method for monitoring thyrophyma-related biomarkers. In this study, a homogeneous electrochemiluminescence immunoassay (HO-ECLIA) coupled with magnetic beads (MBs)-based enrichment tactic was established for the determination of thyrophyma-related thyroglobulin (Tg). Importantly, owing to the abundant surface groups and good biocompatibility of carbon quantum dots (CQDs), the incorporation of CQDs onto the Tg antigen surface was achieved, resulting in the formation of Tg-encapsulated CQDs (CQDs-Tg), which served not only as an ECL probe but as a biorecognition element. Under optimal experimental conditions, the proposed platform demonstrated a wide linear range from 0.01 to 100 ng·mL−1 with a detection limit of 6.9 pg·mL−1 (S/N = 3), and performed well in real serum sample analysis against interference. Collectively, the proposed platform exhibited the rapid response, satisfactory sensitivity and specificity toward Tg in complex serum milieu, and held a considerable potential for clinical prognosis monitoring of thyrophyma. [Display omitted] • A HO-ECLIA platform was constructed based on CQDs and SA-MBs for detection of Tg in serum. • The HO-ECLIA exhibits excellent sensitivity and selectivity for detection of Tg with a detection limit of 6.9 pg mL−1. • This HO-ECLIA platform is expected to provide a scientific basis for the clinical prognosis monitoring of DTC. [ABSTRACT FROM AUTHOR]

The development of the preparation methods for high quality solid state materials is of interest in the area of chemistry, physics and biology. The polymer complex method has been successfully applied for the production of a wide range of solid state materials. This review demonstrates the advantage and limitations of the polymer complex method. Importantly, this is a soft-solution processing method for the production of wide varieties of solid state materials including hybrid and composite materials. [Display omitted] • Polymer complex method is a soft-chemical process which has been successful over last few decades. • Development of the polymer complex method has been described. • Recent literatures on the polymer complex methods have been thoroughly reviewed. • Evidence of facile production of solid state materials by polymer complex method has been outlined. • The broad range of applications of polymer complex method in chemistry, physics and biology have been predicted. 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. [ABSTRACT FROM AUTHOR]

The modification of inert boron nitride by carbon doping to make it an efficient photocatalyst has been considered as a promising strategy. Herein, a highly efficient porous BCN (p-BCN) photocatalyst was synthesized via precursor reconfiguration based on the recrystallization of a new homogeneous solution containing melamine diborate and glucose. Two crystal types of the p-BCN were obtained by regulating the recrystallization conditions of the homogeneous solution, which showed high photocatalytic activities and a completely different CO2 reduction selectivity. The CO generation rate and selectivity of the p-BCN-1 were 63.1 μmol·g−1·h−1 and 54.33%; the corresponding values of the p-BCN-2 were 42.6 μmol·g−1·h−1 and 80.86%. The photocatalytic activity of the p-BCN was significantly higher than those of equivalent materials or other noble metals-loaded nanohybrids reported in the literature. It was found that the differences in the interaction sites between the hydroxyl groups in the boric acid and the homolateral hydroxyl groups in the glucose were directly correlated with the structures and properties of the p-BCN photocatalyst. We expect that the developed approach is general and could be extended to incorporate various other raw materials containing hydroxyl groups into the melamine diborate solution and could modulate precursors to obtain porous BN-based materials with excellent performance. [ABSTRACT FROM AUTHOR]

Influence of rare-earth (La, Ce) and thermo-mechanical treatment on microstructure and mechanical properties of Al-Zn-Mg-Cu alloy are presented in this article. After casting, the alloy which was modified by La, Ce, the grain size of samples obtained around 40-50 µm compared to that of without about 65 µm; and after homogeneous, the grain sizes is about 30 µm. After the cold deformation process, the distance between plates is 10 µm. By EDS after casting, the samples have tended to more La, Ce elements at the grain boundary, after homogeneous, the uniformation distribution of rare-earths was presented by mapping of EDS's results. In addition, after rolling and heat treatment, the elements were found on the grain boundary and matrix. After recrystallization annealing, the grain size is around 10 µm with the modification sample. The grain size was reduced by two processes of modification as well as thermal-mechanical treatment is a condition for increasing the ductility of the studied alloy. Further, as a result of ability deformation from the tensile test, these results demonstrate that the tensile test obtained 140 % when adding La, Ce contents into the alloy combine with thermal-mechanical treatment. The combined used of La, Ce and thermal-mechanical treatment have increased the ductility of Al-Zn-Mg-Cu alloy. [ABSTRACT FROM AUTHOR]

Recently, cold atmospheric-pressure plasma has been studied extensively as an efficient and green method to synthesize gold nanoparticles (AuNPs). Although the characteristics of the AuNPs, especially their homogeneousness, depend very much on the plasma synthesis parameters, there is a lack of a study involving these parameters systematically. Moreover, most of AuNPs-cold-plasma synthesis reports so far either required organic capping agents or resulted in highly non-uniform AuNPs. In this work, we systematically study the effect of most important synthesis parametersâ€" including distance from the plasma jet to the solution, gas flow rate, plasma frequency, volume and concentration of the precursor, plasma interaction time as well as the effect of the synthesis environment (humidity and temperature)â€"on the uniformity of the AuNPs. Through various characterization measurements, we show that homogeneous and highly stable intrinsic AuNPs with an average size of 45 nm can be obtained with optimized synthesis parameters and in the absence of a stabilizer. The synthesized AuNPs yield advanced optical sensing properties in comparison with commercial AuNPs and can be further applied in developing versatile and high-sensitivity biosensors. [ABSTRACT FROM AUTHOR]

In this article, we report on demonstrating high-performance AlGaN/GaN high-electron-mobility-transistor (HEMT) on free-standing GaN (FS-GaN) substrate with low contact resistance (${R}_{C}$) and high breakdown voltage (BV). Non-regrowth ${R}_{C}$ as low as $0.23 \Omega \cdot $ mm was achieved by using the self-aligned Ohmic etching process and nonfield plated BV as high as 193 V was also acquired due to the low dislocation density of the epi-layer on FS-GaN substrate. It is found that the reduction of the ${R}_{C}$ is induced by the smaller electron tunneling width across the AlGaN barrier layer, rather than the formation of dislocation related metal spikes. The fabricated GaN HEMT was a peak extrinsic transconductance (${g}_{m}$) of 203 mS/mm and a drain current (${I}_{D}$) ON/OFF ratio of 106–107. Benefited from the low ${R}_{C}$ , a cut-off frequency/maximum oscillation frequency (${f}_{T}/{f}_{max}$) of 26/73 GHz was extracted at a gate length (${L}_{g}$) of 600 nm, yielding a ${f}_{T}\cdot {L}_{g}$ value of 15.6 GHz $\cdot \mu \text{m}$ and a Johnson’s figure-of-merit (J-FOM) of 5.0 THz $\cdot \text{V}$ , which are the highest values among all AlGaN/GaN HEMTs on FS-GaN substrate. This work implies that GaN HEMTs on FS-GaN substrate with low ${R}_{C}$ turn out to be a promising candidate for high-performance radio frequency (RF) power device applications. [ABSTRACT FROM AUTHOR]

This short paper addresses quasi synchronization of linearly coupled heterogeneous systems. Similarity and difference between the complete synchronization of linearly coupled homogeneous systems and the quasi synchronization of linearly coupled heterogeneous systems will be revealed. [ABSTRACT FROM AUTHOR]

Filtration is one of the main impacts on hydraulic structures. This phenomenon causes consequences such as loss of water from reservoirs, force impact on the structure in the form of filtration back pressure or volumetric hydrodynamic filtration forces. In practice, isotropic filtration is more often considered, characterized by the same conductivity of materials in all directions [1]: Kx = Ky. Under the influence of the pressure created by the dam, water is filtered through the body of the dam from the upstream to the downstream. The upper limit of the filtering will be a line called the depression curve. If the depression curve tapers out on the downstream slope of the dam, then there is water filtration under some residual pressure. In this case, the wedged out water begins to flow in streams down the slope surface. The water wedged out on the slope washes soil particles out of the body of the dam. This disturbance of the stability of soil particles, called suffusion, leads to increased filtration, and then to slumping and failure of the downstream slope, which poses a direct threat to the entire dam. The article considers the review problems of mathematical modeling of plane-parallel isotropic fluid filtration. [ABSTRACT FROM AUTHOR]