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The stabilization problem for uncertain discrete‐time singular Markovian jump systems (DSMJSs) with time‐varying delays is comprehensively covered in this paper. An updated Lyapunov–Krasovskii functional is presented via a discrete state decomposition method. With the help of this constructed Lyapunov–Krasovskii functional, some delay‐ and mode‐dependent sufficient conditions for the open‐loop DSMJSs are derived. Based on these circumstances, a memory mode‐dependent state feedback control is used to create a closed‐loop DSMJS with parameter uncertainties that is regular and causal. And then, the stochastically admissible conditions are attained. Through the exact calculation of each decomposition component for the designed memory state feedback controller, the intended memory state feedback controller settings are determined. It should be mentioned that the algorithm suggested in this article expands the controller design's feasibility and flexibility. The numerical results show how the approach is superior to previous ones, and the given results are less conservative. [ABSTRACT FROM AUTHOR]

Soil heavy metal contamination poses a significant threat to both environmental health and ecological safety. To investigate the influencing factors, ecological hazards, and sources analysis of heavy metals in purple soil, 27 sets of soil samples were collected from varying genetic horizons within Guang'an City, and the contents of As, Cd, Cu, Cr, Hg, Ni, Pb, and Zn were analyzed. The results indicated higher concentrations of heavy metals in soil A horizon, compared to that of C horizon. The relevance analysis indicated that the soil's heavy metals were strongly correlated with the soil's physicochemical properties. The enrichment factor, pollution load index, and potential risk index highlighted slightly to severely polluted levels of soil Cd and Hg, which significantly contribute to the ecological hazards posed by soil heavy metals. The potential source of heavy metals analyzed using the APCS-MLR model identified both anthropogenic inputs and natural sources as primary contributors to heavy metal presence in soils. The Cu, Cr, Ni, Pb, and Zn contents in the samples from different genetic horizons were chiefly influenced by natural sources, such as soil matrix erosion and weathering, while the concentrations of Cd and Hg were largely affected by anthropogenic activities, specifically coal combustion and agriculture. Conversely, the As content was found to be influenced by a combination of both factors. Anthropogenic activities greatly impacted soil heavy metals at various depths within the study area, thereby underscoring the importance of monitoring these heavy metals. The findings gained from this research can give a scientific basis for the potential utilization of purple soil. [ABSTRACT FROM AUTHOR]

[Display omitted] Nanoscale graphene-semiconductor composite photocatalysts with fascinating properties in the photocatalytic hydrogen evolution have inspired numerous interests in broad research fields. The architectures with efficient light response and promoting charge separation at the interface between reduced graphene oxide (RGO) and semiconductor are critical, yet synthesizing them remains a formidable challenge. Herein, the photodiode array-like LaNiO 3 /N,P-RGO (LNO/N,P-RGO) nanoreactor was constructed using an innovative strategy of acid etching-induced nanocutting self-assembly. Ammonium dihydrogen phosphate working as both a nitrogen phosphorus co-dopant and an acid etching reagent, cuts perovskite LaNiO 3 (LNO) nanoparticles into nanorods, which are bonded evenly on the nitrogen phosphorus co-doped reduced graphene oxide (N,P-RGO) to form an n-n semiconductor heterojunction LNO/N,P-RGO as a photodiode array-like nanoreactor via hydrothermal treatment. The photodiode array-like nanostructure exposes more active sites that are conducive to light absorption. The robust Ni-C and P-O bonds promote the narrowing of space-charge region at the interface by UV irradiation, thereby improving the transport of photogenerated carriers by visible light irradiation. The LNO/N,P-RGO nanoreactor exhibits excellent photocatalytic hydrogen evolution performance with a yield of up to 354 μmol g−1 h−1 under UV–visible light, which is 50 times higher than that of pure perovskite LNO, and it also displays favorable recycling stability. [ABSTRACT FROM AUTHOR]

This work carefully revisits the topic of dynamic feedback $ H_{\infty } $ H ∞ control problem for discrete singular systems (DSSs) with time–varying delays. A new state decomposed Lyapunov-Krasovskii functional is presented by a discrete state decomposition method. For the unforced nominal DSSs, delay–dependent sufficient conditions with an $ H_{\infty } $ H ∞ performance index are derived. Based on these conditions, a closed–loop system being regular and causal is developed via a dynamic feedback controller. As a new discrete state decomposition–reorganization method is proposed, the required admissibility conditions are attained. Through the accurate calculation of each decomposition component of the dynamic feedback controller, the desired dynamic feedback controller settings are determined. The numerical findings demonstrate the superiority of our method over earlier approachers, and the results are less conservative. [ABSTRACT FROM AUTHOR]

As a new class of soft materials, continuous emulsion channels have been successfully stabilized solely by rough colloids, which exhibit unique capability in sterically controlling liquid–liquid interfaces. Once jammed at the interface, the roughness‐enhanced frictions can slow down the dynamics of phase separation, and the interlocking behaviors would constrain their relative motions and generate force structures that provide mechanical support for the created emulsions. Ethanol is used to ensure the particles' absorption, whose migration can modify the interfacial tension, and increase the solubility of active ingredients (e.g., curcumin). Applying rough colloids in ethanol‐containing systems opens new pathways toward the generation of novel structures and materials, where the parallel but separate functionalities provided by various phases demonstrate wide‐ranging applications, especially in delivery systems with variably soluble components. [ABSTRACT FROM AUTHOR]

In the present study, we conducted a conjugate heat transfer (CHT) analysis for double-wall cooling with impingement and effusion, incorporating various types of ribs, using the Reynolds-averaged Navier–Stokes (RANS) method and the modified shear stress transport (SST) turbulence closure model (SST-KIC), accounting for the Kato-Launder modification (K), intermittency (I), and crossflow (C) transition effects. We comprehensively discussed the impact of slit type (parallel, inclined, convergent, and divergent), open-area ratio (β = 5%, 20%, and 40%), and jet Reynolds number on the turbulent flow and heat transfer in a double-wall cooling with slit ribs. Our findings indicated that the introduction of slit ribs significantly improved heat transfer and its uniformity on the target wall, albeit with a slight increase in pressure loss. The overall Nusselt number and thermal-hydraulic performance (THP) in cases with slit ribs gradually decreased with β, yet remained up to 17% and 13% higher than those observed on a smooth target wall. Notably, the open-area ratio of the slit rib exhibited a more pronounced effect on heat transfer over the target plate. For the divergent slit rib within the Reynolds number range of 4000–16 000, the heat transfer enhancement ratio reached the highest value at β of 0.05. In addition, we computed the entropy production caused by fluid friction and heat transfer, as well as the overall entropy production in double-wall cooling at different β and Re. The analysis revealed that the slit rib target plate performed better than the solid rib target plate, showing a distinct advantage in terms of total entropy production. [ABSTRACT FROM AUTHOR]

The issue of robust stability here is carefully thought about for uncertain neutral type descriptor systems (NTDSs) with mixed delays. An augmented Lyapunov–Krasovskii functional considering the cross information of the singular matrix and state delay derivative is constructed. With the help of the zero‐value equation technique and an improved matrix inequality, a novel delay‐dependent admissible criterion is developed to make sure of the regularity, non‐impulsiveness, and stability of the NTDSs. On this basis, the robust stability of the uncertain NTDSs is further explored, and a novel robust stability criterion is developed. These criteria have less conservatism. Through three number‐based examples, some comparisons are provided to show the superiority and effectiveness of our method. [ABSTRACT FROM AUTHOR]

A locally optimal preconditioned Newton-Schur method is proposed for solving symmetric elliptic eigenvalue problems. Firstly, the Steklov-Poincaré operator is used to project the eigenvalue problem on the domain \Omega onto the nonlinear eigenvalue subproblem on \Gamma, which is the union of subdomain boundaries. Then, the direction of correction is obtained via applying a non-overlapping domain decomposition method on \Gamma. Four different strategies are proposed to build the hierarchical subspace U_{k+1} over the boundaries, which are based on the combination of the coarse-subspace with the directions of correction. Finally, the approximation of eigenpair is updated by solving a local optimization problem on the subspace U_{k+1}. The convergence rate of the locally optimal preconditioned Newton-Schur method is proved to be \gamma =1-c_{0}T_{h,H}^{-1}, where c_{0} is a constant independent of the fine mesh size h, the coarse mesh size H and jumps of the coefficients; whereas T_{h,H} is the constant depending on stability of the decomposition. Numerical results confirm our theoretical analysis. [ABSTRACT FROM AUTHOR]

The organic UVA filter is popularized in sunscreen cosmetics due to the advantages of excellent light stability and high molar extinction coefficient. However, the poor water solubility of organic UV filters has been a common problem. Given that nanoparticles (NPs) can significantly improve the water solubility of organic chemicals. Meanwhile, the excited-state relaxation pathways of NPs might differ from their solution. Here, the NPs of diethylamino hydroxybenzoyl hexyl benzoate (DHHB), a popular organic UVA filter, were prepared by an advanced ultrasonic micro-flow reactor. The surfactant (sodium dodecyl sulfate) was selected as an effective stabilizer to prevent the self-aggregation of the NPs for DHHB. Femtosecond transient ultrafast spectroscopy (fs-TA) and theoretical calculations were utilized to trace and explain the excited-state evolution of DHHB in NPs suspension and its solution. The results reveal that the surfactant-stabilized NPs of DHHB reserve a similarly good performance of ultrafast excited-state relaxation. The stability characterization experiments demonstrate that the strategy of surfactant-stabilized NPs for sunscreen chemicals can maintain its stability and enhance the water solubility of DHHB compared with that of the solution phase. Therefore, the surfactant-stabilized NPs of organic UV filters are an effective method to improve water solubility and keep the stability from aggregation and photoexcitation. [ABSTRACT FROM AUTHOR]

Transition metal compounds, especially NiS 2 , CoS 2 , WS 2 , and MoS 2 as noble metal-free catalyst materials, are widely applied to replace Pt in the fields of dye-sensitized solar cells (DSSCs) and hydrogen evolution reactions (HER). Meanwhile, hollow structures have large specific surface area and their large void spaces can also effectively reduce ion migration resistance and diffusion length. In this work, Ni–CoS 2 /WS 2 and Ni–CoS 2 /MoS 2 hollow cuboids have been successfully synthesized and applied as promising bifunctional electrocatalysts in high-efficiency DSSCs and HERs. In detail, nickel-cobalt hydroxide cuboids were prepared and served as self-sacrificing templates to react with (NH 4) 2 WS 4 or (NH 4) 2 MoS 4 at room temperature, and then mixed with sulfur powder for annealing treatment. Besides, Ni–CoS 2 hollow cuboids were synthesized as a reference. Profiting from the stable hollow structure, large specific surface area, abundant effective active sites exposed by WS 2 , and synergistic effect of multiple elements, Ni–CoS 2 /WS 2 hollow cuboids manifested a preeminent performance. Compared with Pt (8.06%), the conversion efficiency of Ni–CoS 2 /WS 2 hollow cuboids had reached 9.41% as counter electrode for DSSCs. As for HER, it exhibited the lowest overpotential of 72.4 mV@10 mA cm−2 and had the minimum Tafel slope (56.1 mV dec−1) compared with Ni–CoS 2 /MoS 2 and Ni–CoS 2. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, for a linear singular system, the dissipativity and disturbance-rejection problems are considered simultaneously. An improved equivalent-input-disturbance (IEID) method has shown good disturbance-rejection performance for linear systems. Therefore, the objective of this study is to obtain a satisfactory disturbance-rejection performance and dissipativity performance level based on the IEID method for singular systems. First, the influence of exogenous disturbances on the system is estimated based on the IEID method. The estimate is added to the control input channel to offset this influence. A necessary and sufficient condition is obtained to ensure that the singular system is admissible and satisfies dissipativity performance level. Subsequently, a state-feedback controller is designed based on the admissibility condition. Finally, a numerical example is used to demonstrate the validity of the proposed method. [ABSTRACT FROM AUTHOR]

Background: Exposure to heat waves could result in adverse effects on human health, especially in male testicles. PIWI‐interacting RNA (piRNA) is a novel type of small non‐coding RNA, which can notably impact mRNA turnover and preserve germline maintenance in germline cells. However, piRNA's expression status when adapting to testicular heat stress remains largely unclear. Objectives: To investigate the function and mechanisms of relevant piRNAs during testicular heat stress. Materials and methods: In this study, a mouse testicular heat stress model was constructed, and the testes were removed for piRNA‐sequencing. Bioinformatics analysis was used to discover the differential expressed piRNAs, piRNA clusters, and enriched pathways. A cell heat stress model was constructed to validate the top five upregulated piRNAs. Proliferation and apoptosis assays were utilized to validate the function of selected piRNA. Bioinformatics prediction, western blotting, and immunohistochemistry were used to illustrate the downstream mechanisms. Results: Through the bioinformatics analysis, we identified the differential expression profile and enriched pathways of piRNAs and piRNA clusters during testicular hyperthermia. Besides, piR‐020492 was proved to be upregulated in heat stress mouse testes and a germ cell model. A series of in vitro assays illustrated that an overexpression of piR‐020492 could restrain the proliferation and promote the apoptosis of mouse germ cells. Kyoto Encyclopedia of Genes and Genomes analysis of piRNA‐generating genes in the testicular heat stress model and piR‐020492 targeting genes showed that the overlap pathways are adenosine monophosphate–activated protein kinase (AMPK) and insulin pathways. Validation experiments demonstrated that the key genes of AMPK and insulin pathway exhibit differential expression after an overexpression of piR‐020492 or testicular heat stress. Discussion and conclusion: In conclusion, our findings revealed the expression profile of piRNAs in testicular heat stress and illustrated the function and mechanisms of piR‐020492 in germ cells, which could provide novel insights into the mechanism of hyperthermia‐induced testicular injury. [ABSTRACT FROM AUTHOR]

Background: The long-term prognosis of current treatments for anal sphincter incontinence (ASI) is poor. Here, we explored the efficacy of tissue adipose stromal vascular fraction SVF (tSVF) on ASI and compared it to that of cellular SVF (cSVF). We then investigated possible mechanisms. Methods: Rat cSVF and tSVF were isolated and labeled with DIL. One day after modeling, three groups received phosphate-buffered saline (PBS), cSVF, tSVF, respectively. The control group received nil modeling nor any treatments. The effect was assessed by function test for anal pressure and electromyography, and staining for fiber content, proliferation and differentiation at day 5 and day 10. Results: cSVF injection resulted in faster healing than tSVF. The cSVF group showed significant improvement on anal pressure on day 10. For the electromyography test, cSVF showed significant improvement for the frequencies on day 10, and for the peak values on both time points, while tSVF showed significant improvement for the peak values on day 10. The two SVF both alleviated fibrosis. Immunofluorescence tracing identified differentiation of some injected cells towards myosatellite cells and smooth muscle cells in both SVF groups. For all the tests, the tSVF group tends to have similar or lower effects than the cSVF group with no significant difference. Conclusion: cSVF and tSVF are both safe and effective in treating ASI, while the effect of cSVF is slighter higher than tSVF. [ABSTRACT FROM AUTHOR]

The security of most lattice-based cryptography schemes are based on two computational hard problems which are the short integer solution (SIS) and learning with errors (LWE) problems. The computational complexity of SIS and LWE problems are related to approximating shortest vector problem and bounded distance decoding (BDD) problem. Approximating BDD is a special case of approximating closest vector problem (CVP). In this paper, we revisit the study for approximating CVP. We give a proof that approximating the CVP over |$\ell _\infty $| -norm (CVP |$_\infty $|⁠) within any constant factor is NP-hard. The result is obtained by the gap-preserving reduction from Min Total Label Cover problem in |$\ell _1$| -norm to to CVP |$_\infty $|⁠. This proof is simpler than known proofs [ 10 ]. [ABSTRACT FROM AUTHOR]

In this paper, we propose a decoupled stabilized finite element method for the time–dependent Navier–Stokes/Biot problem by using the lowest equal‐order finite elements. The coupling problem is divided into two subproblems which can be solved in parallel: One is the Navier–Stokes model by treating the nonlinear term explicitly, and the other is the Biot model. In the numerical scheme, we use the implicit backward Euler method in time, while treat the coupling terms explicitly. The stability analysis and error estimates are established for the proposed fully discrete scheme. Numerical results are provided to justify the theory. [ABSTRACT FROM AUTHOR]

We propose two mass and heat energy conservative, unconditionally stable, decoupled numerical algorithms for solving the Cahn–Hilliard–Navier–Stokes–Darcy–Boussinesq system that models thermal convection of two‐phase flows in superposed free flow and porous media. The schemes totally decouple the computation of the Cahn–Hilliard equation, the Darcy equations, the heat equation, the Navier–Stokes equations at each time step, and thus significantly reducing the computational cost. We rigorously show that the schemes are conservative and energy‐law preserving. Numerical results are presented to demonstrate the accuracy and stability of the algorithms. [ABSTRACT FROM AUTHOR]

In this article, a decoupled modified characteristic finite element method is proposed for the time‐dependent Navier–Stokes/Biot problem. In the numerical scheme, the implicit backward Euler scheme is used for the time discretization, whereas the coupling terms are treated explicitly. At each time step, we only need to solve two decoupled problems, one is the Navier–Stokes equations solved by the modified characteristic finite element method, and the other is Biot equations. The stability and the error estimates are established for the proposed fully discrete scheme. Numerical experiments are provided to illustrate the theory. [ABSTRACT FROM AUTHOR]

Simple Summary: Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) was first observed in tobacco in Greece in 1889. In China, since the introduction of Euphorbia pulcherrima (Euphorbiales: Euphorbiaceae, native to Central America) at the end of the previous century, B. tabaci has gradually become an increasingly significant agricultural pest. In recent years, the push–pull strategy has been widely applied to the control of the pest. The distinct volatiles are emitted of plants directly affect the efficiency of pushing and pulling; hence, we aimed to study the behavioral responses of B. tabaci to three plants (Gossypium hirsutum, Abutilon theophrasti, and Ricinus communis) during various growth phases (pre-flowering, fluorescence, and fruiting) and analyzed the quality and quantity of volatiles from of three growth stage, as well as identified few compounds that attract or repel the B. tabaci. The results demonstrated that the distinct volatiles are emitted by pre-flowering, flowering, and fruiting plants with varying effects on B. tabaci preference. Three volatile compounds (linalool, (Z)-3-hexenyl acetate, and nonanal) analyzed in this study had trapping/repellent effects on B. tabaci. Therefore, these compounds can be adopted as potential attractants or repellents to control B. tabaci. Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a worldwide pest that damages over 900 host plant species. The volatile organic compounds (volatiles) of contrasting plants, as well as their growth stage, influence this pest's infestation behavior. The chemical contents of volatiles isolated from three plants (Gossypium hirsutum, Abutilon theophrasti, and Ricinus communis) during various growth phases (pre-flowering, fluorescence, and fruiting) were examined, as well as their influence on the behavior of adult B. tabaci. The olfactometer studies demonstrated that growth periods of the three plants affected the preference of B. tabaci. Volatiles of piemarker and cotton plants had dissimilar levels of attraction to adults during all stages. Volatile substances released by the castor at the stage of flowering had repellent effect on B. tabaci. In the plant versus plant combination, piemarker volatiles before and during anthesis were most preferred by adults, followed by cotton and then castor. A total of 24, 24, and 20 compounds were detected from volatiles of piemarker, cotton, and castor, respectively, and proportions among the compounds changed during different stages of plant development. The olfactory responses of B. tabaci to volatile compounds presented that linalool and high concentration of (Z)-3-hexenyl acetate had a strong trapping effect on this pest, while nonanal had a significant repellent effect at high concentration. This study indicates that distinct plants and their growth stage affect their attractiveness or repellency to B.tabaci adults, which are mediated by changing plant volatiles. These compounds obtained by analysis screening can be adopted as potential attractants or repellents to control Mediterranean (MED) B. tabaci. [ABSTRACT FROM AUTHOR]

We analyze a fully discrete finite element numerical scheme for the Cahn–Hilliard–Stokes–Darcy system that models two-phase flows in coupled free flow and porous media. To avoid a well-known difficulty associated with the coupling between the Cahn–Hilliard equation and the fluid motion, we make use of the operator-splitting in the numerical scheme, so that these two solvers are decoupled, which in turn would greatly improve the computational efficiency. The unique solvability and the energy stability have been proved in Chen et al. (2017, Uniquely solvable and energy stable decoupled numerical schemes for the Cahn–Hilliard–Stokes–Darcy system for two-phase flows in karstic geometry. Numer. Math. , 137 , 229–255). In this work, we carry out a detailed convergence analysis and error estimate for the fully discrete finite element scheme, so that the optimal rate convergence order is established in the energy norm, i.e. in the |$\ell ^{\infty } (0, T; H^1) \cap \ell ^2 (0, T; H^2)$| norm for the phase variables, as well as in the |$\ell ^{\infty } (0, T; H^1) \cap \ell ^2 (0, T; H^2)$| norm for the velocity variable. Such an energy norm error estimate leads to a cancelation of a nonlinear error term associated with the convection part, which turns out to be a key step to pass through the analysis. In addition, a discrete |$\ell ^2 (0;T; H^3)$| bound of the numerical solution for the phase variables plays an important role in the error estimate, which is accomplished via a discrete version of Gagliardo–Nirenberg inequality in the finite element setting. [ABSTRACT FROM AUTHOR]

Background: Anal sphincter incontinence (ASI) can cause a serious decline in the quality of life and can cause a socioeconomic burden. Studies have shown that bone marrow mesenchymal stem cells (MSC) have significant therapeutic effects on ASI, but the cost and risk of MSC harvest limit their further application. In contrast, adipose tissue derived stem cells (ADSC) and cellular stromal vascular fraction (CSVF) as stem cell sources have multipotency and the advantage of easy harvest. Objective: Here we aim to investigate the effects of ADSC and CSVF on treating ASI and compare them to that of bone marrow MSC. Methods: Bone marrow MSC, ADSC, and CSVF were obtained and labeled with green fluorescent protein (GFP), and CSVF was labeled with DIL. Sprague Dawley (SD) rats were divided into 5 groups. Four groups were injected with 0.2 mL phosphate buffer saline (PBS), 1 × 107/0.2 mL of MSC, ADSC, or CSVF, respectively, after model establishment. The control group received no treatment. The repair was assessed by anal functional tests and immunostaining on day 5 and day 10 after injection. Results: MSC, ADSC, and CSVF significantly promoted tissue repair and the recovery of muscle contraction and electromyographic activity in ASI. The generation of myosatellite cells by injected MSC, ADSC, and CSVF was found in the wounded area. On day 5, CSVF showed highest therapeutic effect, while on day 10, MSC and ADSC showed higher therapeutic effects than CSVF. When comparing the effects of MSC and ADSC, ADSC was slightly better than MSC in the indexes of anal pressure, etc. Conclusion: ADSC and CVSF are alternative stem cell sources for ASI repair. [ABSTRACT FROM AUTHOR]

The mechanisms of dehydrogenation reactions as important processes in methanol to aromatics (MTA) have been controversial. Recent work on the active center for dehydrogenation at either Lewis acid site (LAS) or Brønsted−Lewis (B−L) acid synergistic site is a matter. The dehydrogenation processes on L−acid site (GaO+) or B−L acid site (H+ − GaO+) over GaO+/HZSM-5 with different Lewis acid locations for n -hexene to 1,5-hexadiene, as well as cyclohexene to benzene have been researched by applying the density functional theory (DFT) method. The results reflect that active center of dehydrogenation reactions is B−L acid synergistic site through B−L acid synergy mechanism. All elementary steps including C−H bond activation, the formation of H 2 , hydrogen transfer as well as the regeneration of B−acid site are easy to proceed. However, the isomerization for carbonium ions from GaO+ to skeleton oxygen of zeolites is relatively difficult. The analysis shows that isomerization is influenced by the structural and electronic properties of carbonium ions chemisorbed on zeolites. Lewis acid strength of GaO+/HZSM-5 and energy gap between HOMO and LUMO on adsorption complexes are appropriate descriptors for the C−H bond activation. The rate constants analysis indicates that increasing temperature is more favorable for C−H bond activation. Further considering that C−H bond activation occurred preferentially than isomerization, it could be a critical initial step to primarily screen catalysts. [Display omitted] • The active center of dehydrogenation is B−L acid (H+−GaO+) synergistic site. • C−H bond activation and isomerization are key processes. • Lewis acid strength and energy gap are descriptors for C−H bond activation. [ABSTRACT FROM AUTHOR]

A class of nonlinear Fokker–Planck equations with nonlocal interactions may include many important cases, such as porous medium equations with external potentials and aggregation–diffusion models. The trajectory equation of the Fokker–Plank equation can be derived based on an energetic variational approach. A structure‐preserving numerical scheme that is mass conservative, energy stable, uniquely solvable, and positivity preserving at a theoretical level has also been designed in the previous work. Moreover, the numerical scheme is shown to satisfy the discrete energetic dissipation law and preserve steady states and has been observed to be second order accurate in space and first‐order accurate time in various numerical experiments. In this work, we give the rigorous convergence analysis for the highly nonlinear numerical scheme. A careful higher order asymptotic expansion is needed to handle the highly nonlinear nature of the trajectory equation. In addition, two step error estimates (a rough estimate and a refined estimate) are necessary in the convergence proof. Different from a standard error estimate, the rough estimate is performed to control the nonlinear term. A few numerical results are also presented to verify the optimal convergence order and the preservation of equilibria. [ABSTRACT FROM AUTHOR]

Printed Circuit Board (PCB) is the heart component of electronic products, and its defect detection is the basic requirement of PCB quality control in the production process. Traditional visual detection methods need artificial design features, so their detection accuracy is poor, and the rate of missed and false detection is high. To solve the above problems, this paper proposes an improved YOLOv3 (You Only Look Once) detection method for PCB plug-in solder spot defects based on the combination of the ordered probability density weighting and the attention mechanism. First, in order to obtain a higher priority priori box, the ordered probability density weighting (OWA) method is used to optimize the multiple sets of a priori boxes generated by K-means. Then, to get more effective feature information, the Squeeze-and-Excitation mechanism (SE) is added to the backbone network. In the feature detection network, the Convolutional Block Attention Module (CBAM) attention mechanism is joined, at the same time in the inspection network output layer three layer feature are fusions. Finally, in order to accelerate the convergence speed of model and improve the accuracy of the model, the network loss function was improved by using the generalized joint generalized intersection over union (GIoU), and the COCO data model was applied to PCB solder spot defect training by transfer learning method. After testing, the average detection accuracy of improved network is improved from 84.35% to 96.69%, and the improved network has better convergence than the original network. The study shows that the improved method based on YOLOv3 is more suitable for industrial application of PCB plug-in solder spot defect detection. [ABSTRACT FROM AUTHOR]

Scheme of rational designed H+/GCL-chitosan for high nitrite adsorption capacity. [Display omitted] • A feasible new strategy to enhance the nitrite adsorption of chitosan • Protonated imines are excellent anion adsorption sites • H+/GCL-chitosan has the highest nitrite adsorption capacity among chitosan adsorbents • Rapidly removing 95% of nitrite from high-concentration nitrite solution Removing hazardous nitrite from water by chitosan has many advantages such as low cost, biocompatible, and abundant availability. However, its poor adsorption capacity for nitrite hinders its practical applications. More importantly, the strategies for improving the nitrite adsorption ability of chitosan are still elusive. In this work, a systematic strategy that considers adsorption sites, surface potential, and crystallinity was proposed to enhance the nitrite adsorption of chitosan. As a demonstration, a rationally designed amorphous adsorbent (H+/GCL-chitosan) with imine adsorption sites and positive surface Zeta potential was synthesized via heterogeneous cross-linking with glutaraldehyde and then acidified in HCl solution. The obtained adsorbent exhibited a high nitrite adsorption capacity of 17.30 mg·N·g−1, far surpassing the previously-reported chitosan-based adsorbents. Theoretical calculations and mechanism studies indicated that the designed imine adsorption sites and positive surface Zeta potential are crucial for its excellent adsorption capacity. Furthermore, H+/GCL-chitosan can rapidly reach adsorption equilibrium within 3 min and maintain stable adsorption for 24 h, and the adsorbent can be regenerated effectively. To demonstrate its applications, two H+/GCL-chitosan adsorption devices achieved over 95 % of nitrite removal rate with the initial nitrite concentrations of 10 and 100 mg·N·L−1 respectively, without any pretreatment of the polluted water. These results clearly show that H+/GCL-chitosan has an excellent ability for nitrite removal. Moreover, the surface engineering strategy proposed in this work may open up new possibilities for the efficient removal of nitrite from water using chitosan-based adsorbent. [ABSTRACT FROM AUTHOR]

The methylation of toluene with methanol is an important process for the preparation of p-xylene (PX). The modification of Ni-containing species in HZSM-5 can improve the yield of PX. However, the active site existence form of Ni is unclear. The intrinsic reaction mechanisms for methylation of toluene with methanol over HZSM-5 with NiOH+ and Ni2+ as Lewis acid have been investigated. The results indicate that the introduction of Ni2+ decreases the activity for the methanol dissociation, whereas NiOH+ enhances the activity with a reduction in activation energy of 100.7 kJ/mol. Furthermore, the generation of three xylenes, as well as the conversion of PX to 1,2,4-Trimethylbenzene (1,2,4-TMB) have also been studied over NiOH+/HZSM-5. It is shown that PX is most easily formed with the lowest energy barrier of 84.8 kJ/mol in four products, implying the introduction of NiOH+ in HZSM-5 favors the formation of PX. In addition, molecular dynamics simulations show that toluene reacts with methanol to form xylenes mainly at the intersection of channels. PX exhibits a much higher self-diffusion coefficient than MX and OX when the temperature rises from 498 to 698 K. It can be concluded that NiOH+ is the active Ni-containing species and NiOH+/HZSM-5 is an excellent catalyst for the production of PX via the methylation of toluene with methanol. [Display omitted] • NiOH+/HZSM-5 has high activity for methanol dissociation. • The lower activation energy is needed for PX formation than that for MX, OX and 1,2,4-TMB. • The more negative charge methanol receives, the more easily it dissociates. • NiOH+/HZSM-5 (T7-2) exhibits excellent channel shape selectivity to PX. [ABSTRACT FROM AUTHOR]

In a proxy re-signature scheme, a semi-trusted proxy can convert Alice's (also called as delegatee's) signature into Bob's (also called as delegator's) signature on the same message. However, the proxy itself cannot produce any signatures on behalf of either Alice or Bob. There exists some unidirectional one-use and multi-use (a message can be re-signed a polynomial number of times) proxy re-signature schemes. In some scenarios of big data, it is required to design unidirectional infinite-use (a message can be re-signed infinite number of times) proxy re-signature schemes. In this paper, we propose the first unidirectional infinite-use proxy re-signature scheme and identity-based unidirectional infinite-use proxy re-signature scheme with private re-signature keys based on lattice and prove that they are secure in the random oracle model. [ABSTRACT FROM AUTHOR]

Neonicotinoid pesticides are widely applied for controlling pests in a variety of agriculture crops. Due to the systemic distribution in plants, neonicotinoid pesticides have been found in nectar and pollen, which are the main source of food for the important pollinator honeybee. The risk of neonicotinoid residues in honeybee products and honeybee has caused great attention since their impacts on the environment, ecology, and food safety issues. These concerns require the accurate and sensitive determination of neonicotinoids and their metabolites in the honeybee products and honeybee. Since the trace residue level of neonicotinoid and the complexity of the samples, analysis of neonicotinoid targets in these important matrices is still a great challenge. The present review provides general overview of analytical methods for the determination of neonicotinoid pesticides and their metabolites in honeybee products and honeybee. [ABSTRACT FROM AUTHOR]

The issue of the reliable exponential H∞ filtering (HF) is revisited for singular Markovian jump time‐delay systems (SMJTSs) accompanied by sensor failures and interval time‐varying delays. By a new mode‐dependent Lyapunov–Krasovskii functional (LKF) containing three augmented nonintegral terms, some mean‐square exponentially admissible (MSEA) conditions satisfying an H∞ performance are derived subject to state decomposition method. On this basis, a novel reliable filter design approach is first proposed for SMJTSs by means of the idea of the state decomposition and recombining. And the filter parameters we want can be obtained. Worth noting that the results presented are not only related to interval time‐varying delay and sensor failure but also to interval delay‐change‐rate. Meanwhile, the sufficient conditions established have less conservatism and lower computational complexity in comparison with the existing results. The effectiveness and superiority of the proposed methods are verified by two numerical examples derived from some existing papers. [ABSTRACT FROM AUTHOR]

The identification and quantification of the ecological risks, sources and distribution of heavy metals in purple soils are essential for regional pollution control and management. In this study, geo-accumulation index (Igeo), enrichment factor (EF), pollution index (PI), potential ecological risk index (RI), principal component analysis (PCA) model and geographical detector (GD) were combined to evaluate the status, ecological risk, and sources of heavy metals (HMs) in soils from a typical purple soil areas of Sichuan province. The results showed that the average contents of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn in purple soil were 7.77, 0.19, 69.5, 27.9, 0.077, 30.9, 26.5 mg/kg and 76.8 mg/kg, and the Igeo, EF and RI of topsoil Hg and Cd in designated area was the highest, and the average contents of Hg and Cd in topsoil were obviously greater than respective soil background value in Sichuan province and purple soil. The hot spots for the spatial distribution of 8 HMs were mainly focused in the southwest and northeast of the designated area, and there were also significant differences for 8 HMs distribution characteristics in the profile soil. Cu comes from both anthropogenic and natural sources, Zn, Ni and Cr mainly come from natural sources, but As, Pb, Hg and Cd mainly derived from human activities. GD results showed that soil texture (X18), altitude (X4), total nitrogen (TN), clay content (X3), sand content (X2) and silt content (X1) had the greatest explanatory power to 8 HMs spatial differentiation.This study provides a reference for understanding the status and influencing factors of HM pollution in typical purple soil, and lays a theoretical foundation for the environmental treatment of purple soil in China. [ABSTRACT FROM AUTHOR]

Objectives. Nonalcoholic fatty liver disease (NAFLD) and hyperlipidemia (HL) are common metabolic disorders due to overnutrition and obesity. NAFLD is often associated with hyperlipidemia. The aim of this study was to identify and compare the erythrocyte membrane lipids profile in NAFLD patients with or without HL. Methods. A total of 112 subjects (with similar age and body mass index) were divided into four groups: (1) normal controls, (2) NAFLD alone, (3) HL alone, and (4) NAFLD combined with HL (NAFLD + HL). Lipid was extracted from the erythrocyte membrane, and lipid profiles of subjects were analyzed by liquid chromatography mass spectrometry (LC-MS). Results. Data sets from 103 subjects were adopted for lipidomic analysis. Significant changes of lipid species were observed in patient groups, especially in the HL group and NAFLD + HL group. The HL group showed increased level of most lipid species, and decreased level of most lipid species was observed in the NAFLD + HL group. The weight percent of myristic acid, stearic acid, erucic acid, and docosahexaenoic acid also showed distinct variation between different groups. Conclusions. NAFLD, HL, and NAFLD + HL all had an impact on lipid profiling of the erythrocyte membrane. The influence of NAFLD alone is less important compared with HL. Some lipids should be highlighted because of their specific role in cell function and systemic metabolism. [ABSTRACT FROM AUTHOR]

Two trials were conducted as follows: the first trial was a 90-day experiment to determine the effects of reducing feeding level on shrimp status; the second trial (90 days) is based on the first trial to explore the suitable C/N ratio of biological flocs for shrimp culture in outdoor soil ponds. Results showed that the BFV levels increased gradually and then tended to be stable in the treatment groups. Concentrations of TAN and NO 2 –N were maintained low level in each treatment pond during experimental period. The final body weight, biology body length and yield of the shrimp in each trial with no significantly different (P > 0.05) while food coefficient and THC of the shrimp in 70% feeding level and C/N12 treatment were slightly lower than in the 100% feeding level and C/N16 treatment respectively (p < 0.05). The antibacterial activity and bacteriolytic activity in C/N16 treatment group were higher than in C/N12 (p < 0.05), while there were no significant difference between the two feeding levels (70%,100%) (P > 0.05). The shrimp in 70% feeding level and C/N12 treatment had the higher T-AOC in both the plasma and the hepatopancreas when compared with 100% feeding level and C/N16 treatment group (p < 0.05). The SOD activity of plasma in 70% treatment group was higher than in 100% (p < 0.05), while it was no significant difference between the two C/N ratios (12,16) in both the plasma and the hepatopancreas (P > 0.05). The effects of two feeding levels and C/N ratios on the GSH level and the ratio of GSH/GSSG in the plasma and the hepatopancreas of shrimp showed no significant difference (P > 0.05). The results showed that 70% feeding level and C/N12 ratio could provide adequate nutrition for shrimp to maintain a normal physical health status with the presence of bioflocs. • Bioflocs helped to maintain good water quality in outdoor soil pond culture. • Feeding level reduced from 100% to 70%, didn't affect the survival and growth of shrimp. • The growth and physiological health of shrimp were not significantly affected when C/N ratio at 12. • Feeding level at 70% and C/N ratio at 12 decreased food coefficients without affecting yield of shrimp. • A new model of shrimp culture in the bioflocs system of outdoor earth pond was established. [ABSTRACT FROM AUTHOR]

The synthesis conditions of HZSM-5 zeolite, including crystallization temperature, crystallization time and raw material ratio, were investigated by L32 (48) orthogonal test to specifically optimize its performance in dimethyl ether (DME) aromatization for the first time. Based on the total yield of aromatic products, the synthesis conditions of HZSM-5 zeolite with the best DME aromatization properties were obtained by comprehensive analysis and validation experiments. The relationship between the aromatization performance, crystalline structure, pore structure, and acidity of HZSM-5 zeolite were analyzed. The results showed that the HZSM-5 zeolite accompanied by hierarchical structure, an appropriate Brønsted and Lewis acid content and uniform crystal morphology, was successfully synthesized under optimized conditions. Over this unmodified and un-doped catalyst, the conversion of DME approached to 99.3% and the total yield of aromatics reached was 53.5%. [ABSTRACT FROM AUTHOR]

In this paper, a stabilized second order in time accurate linear exponential time differencing (ETD) scheme for the no-slope-selection thin film growth model is presented. An artificial stabilizing term Aτ2∂Δ2u∂t A τ 2 ∂ Δ 2 u ∂ t $ A{\tau }^2\frac{\mathrm{\partial }{\Delta }^2u}{\mathrm{\partial }t}$ is added to the physical model to achieve energy stability, with ETD-based multi-step approximations and Fourier collocation spectral method applied in the time integral and spatial discretization of the evolution equation, respectively. Long time energy stability and detailed 𝓁∞(0,T;𝓁2) l ∞ (0 , T ; l 2) $ {\mathcal{l}}^{\mathrm{\infty }}(0,T;{\mathcal{l}}^2)$ error analysis are provided based on the energy method, with a careful estimate of the aliasing error. In addition, numerical experiments are presented to demonstrate the energy decay and convergence rate. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of delay-dependent stability analysis for systems with interval time-varying delay. By means of a new double free-matrix-based integral inequality and augmented Lyapunov–Krasovskii functionals containing as much information of time-varying delay as possible, a new stability criterion for systems is established. Firstly, by a double integral term two-step estimation approach and combined with single free-matrix-based integral inequalities, a stability criteria is presented. Then, compared with the double integral term two-step estimation approach, the proposed new double free-matrix-based integral inequality with more related time delays has potential to lead to a criterion with less conservatism. Finally, the validity of the presented method is demonstrated by two numerical examples. [ABSTRACT FROM AUTHOR]

The aim of this work was to prepare a novel antioxidant film by incorporating α-tocopherol-chitosan nanoparticles (TOC-CSNPs) with chitosan/montmorillonite film (namely, TOC-CSNPs/CS/MMT), and investigate the antioxidant activity of TOC-CSNPs/CS/MMT film on sliced dry-cured ham in a period of 120 days at 4 °C. Positively charged TOC-CSNPs with the average sizes of 214 nm were prepared using TPP-initiated ionic gelation mechanism. The amount of TOC-CSNPs was optimized based on the changes of water vapor permeability (WVP), water solubility and swelling ratio of the film. The TOC-CSNPs/CS/MMT film showed 46.5% radical scavenging activity after 16 days of storage, which was 23 times and 27 times higher than that of CS/MMT and CS film, respectively. The antioxidant activity of TOC-CSNPs/CS/MMT film was evaluated by measuring the peroxide value (POV) and thiobarbituric acid reactive substances (TBARS) values of sliced dry-cured ham coated with the TOC-CSNPs/CS/MMT film-forming solutions. The results indicated that compared with the CS (0.42 g/100 g for POV, 0.65 mg/kg for TBARs) and CS/MMT (0.38 mg/kg for POV, 0.59 mg/kg for TBARs) films, the biceps femoris muscle of the sliced ham coated with TOC-CSNPs/CS/MMT film showed much lower values of POV (0.15 g/100 g) and TBARs (0.15 mg/kg) during 120 days of storage. These results provide a theoretical basis for developing efficient and long-term antioxidant approach, which is crucial for improving and enhancing the quality of food products. • α-tocopherol-chitosan nanoparticles were added into chitosan/montmorillonite film. • The prepared film showed lower water vapor permeability and water solubility. • The amended film retained stronger radical-scavenging activity after 16 days storage. • The sliced ham coated with the film showed much lower TBARs values during 120 days. • The addition of TOC-CSNPs greatly enhanced the antioxidant activity of CS/MMT film. [ABSTRACT FROM AUTHOR]

Two novel kinds of photoinitiators were synthesized used as type II polymerizable photoinitiators with good migration stability in comparison with BP and ITX. The photoinitiator BRA exhibits only about 10% migrant value of BP and TXRA has 12%–25% migrant value of ITX. • Two novel kinds of low migration photoinitiators BRA and TXRA were synthesized. • The spectral properties were studied by Ultraviolet–Visible (UV–vis) spectroscopy. • The photo-initiating activity of the initiators was evaluated by real-time RT-IR. • The synthesized photoinitiators show almost similar initiating activity as the reference. • The synthesized photoinitiators exhibit about 10%–25% migrant value of the reference. Two novel kinds of low migration photoinitiators BRA and TXRA based on benzophenone (BP) and thioxanthone (ITX) were synthesized and used as Type II polymerizable photoinitiators. The structures were confirmed by proton nuclear magnetic resonance (1H NMR), carbon nuclear magnetic resonance (13C NMR), FT-IR and high resolution MS. The spectral properties were studied by Ultraviolet–Visible (UV–vis) spectroscopy. The photo-initiating activity of the initiators was evaluated by real-time RT-IR in the presence of a hydrogen donor such as triethylamine. The results show that they exhibited almost similar initiating activity as the reference BP or ITX, while exhibiting more low migration than the non-functionalized BP or ITX. These results suggest that BRA or TXPA is an efficient photoinitiator for reducing migration in photo-curing system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three biomass ash on the performance of red mud oxygen carrier were studied. • A potential method to improve the attrition resistance of OCs was proposed. • Fiber structure was identified in corn straw ash-modified red mud oxygen carrier. • Mechanism of fiber structure on the improvement of attrition resistance was studied. Chemical looping combustion (CLC) relies on cyclic circulation of oxygen carriers (OCs) between fuel reactor and air reactor to transfer lattice oxygen and heat. OCs' attrition is an important issue hindering large scale application of CLC technology. Attrition is caused by cracks and abrasion, and method to stop crack propagation is an effective way to mitigate attrition. Biomass ash contains inert and alkali metal components, and it may have the potential to increase the reactivity and reinforce the skeleton structure of OCs. The effects of rape straw ash, corn straw ash and bagasse ash on the reactivity, cumulative attrition rate of red mud OCs were evaluated, and their effects on skeleton structure were analyzed, and finally, the strengthening mechanism of OCs skeleton structure was proposed. The results showed that the rape straw ash rich in K and Ca components promoted the reactivity of OCs. Although the Si-rich bagasse ash decreased the reactivity of OCs, it improved the attrition resistance of OCs. Corn straw ash rich in K and Si components was an effective skeleton strengthening material, which improved both the reactivity and the attrition resistance. The cumulative attrition rate of red mud was 2.74%, and the cumulative attrition rate of CSA sample was 0.35%, which was 87.32% lower than that of OC sample, indicating fine attrition resistance. The fiber structure could strengthen the skeleton of OC, therefore, decreasing attrition rate. [ABSTRACT FROM AUTHOR]

To elucidate the effects of NO2 and H2O molecules on the surface conductivity of hydrogenated diamond film, models of various adsorbates containing different molecular ratio of NO2 and H2O on hydrogenated diamond (100) surfaces were constructed. The adsorption energies, equilibrium geometries of adsorbates, density of states, and atomic Mulliken populations were studied by using first‐principles method. The results showed that H2O molecule in the adsorbate could weaken the interactions between the adsorbates and hydrogenated diamond surface significantly. Compared with H2O molecule, NO2 molecule relaxes more dramatically when adsorbed on hydrogenated diamond surface. In addition, density of states for C(100):H–2NO2, C(100):H–NO2, and C(100):H–NO2 + H2O systems are very similar to each other, which indicates an obvious peak at valence band maximum level for all the three samples. It can be attributed to mainly single occupied molecule orbital of NO2 molecule and slightly C–H bond of C(100):H substrate. When the adsorbates contain one NO2 and two H2O molecules, the peak shifts slightly into valence band, but its intensity increases significantly. All the samples exhibit p‐type surface conductivity when adsorbed with pure NO2 molecules, and the surface conductivity remains as H2O molecules added into the NO2 adsorbate layer. However, for oxygenated diamond surface, very week interactions generate between diamond surface and various adsorbates. All the oxygenated diamond (100) surfaces with various adsorbates containing different NO2 and H2O molecules on it exhibit an insulating property. [ABSTRACT FROM AUTHOR]

The world-wide higher education has experienced rapid development since the education reform in recent years, and a lot of money has been invested for the university’s infrastructure and new campuses expansion. However, the exceed expansion of new campuses make the university’s funds allocated from governments and self-held enterprises cannot meet the requirements of university’ normal development, and therefore most universities are burdened by a large amount of debts which can bring out a series of financial risks. According to the classification of university financial risk, the risk sources and potential dangers are analyzed in this study, based on which the university financial risk warning index system and the framework of university financial risk integrated control system are obtained, which are both significant for the university financial risk management. [ABSTRACT FROM AUTHOR]

The designing of efficient and stable electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are vital for boosting the efficiency of overall water splitting. Here, we reported an original design and synthesis of quaternary non-noble metal-based hierarchical core-shell structural nanorods (Ni 2 P/NiMoO 4 @CoP/FeP 2) by hydrothermal reaction, in-situ coating reaction and phosphating processes. The unique core-shell structures increased the number of active sites, which provided favorable conditions for electrochemical catalytic reactions, and the metal phosphide/metal oxide also speeded up the rate of water splitting. In addition, the synergistic effect between metal phosphides also optimized the electrochemical catalytic performance of Ni 2 P/NiMoO 4 @CoP/FeP 2 in the alkaline solution. Ni 2 P/NiMoO 4 @CoP/FeP 2 displayed prominent electrocatalytic performance for HER and OER with overpotentials of 105 and 216 mV at 10 mA cm−2 and small Tafel slopes of 74.4 and 77.8 mV dec−1 in 1.0 M KOH, respectively. When the as-prepared materials were loaded to the anode and cathode of the two-electrode overall water splitting device, only a cell voltage of 1.56 V was required to reach a current density of 10 mA cm−2 and the materials also exhibited good long-term stability. [Display omitted] • Hierarchical core-shell Ni 2 P/NiMoO 4 @CoP/FeP 2 nanorod was facilely synthesized. • Ni 2 P/NiMoO 4 @CoP/FeP 2 had small Tafel slopes and overpotentials in HER and OER. • Ni 2 P/NiMoO 4 @CoP/FeP 2 had good catalytic activities for overall water splitting. • Ni 2 P/NiMoO 4 @CoP/FeP 2 had excellent stability during the long-term tests. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface selenation strategy is performed on metal cocatalysts for enhanced CO 2 -to-CH 3 OH conversion. • Stacked photocatalysts with metal core sandwiched between semiconductor and selenated shell are fabricated. • Metal core accelerates the migration of photoelectrons from semiconductor to selenated shell. • Selenated shell decreases the energy barriers for CH 3 OH production and inhibits the side H 2 evolution. Solar-driven reduction of CO 2 and H 2 O to methanol is highly desirable owing to multiple advantages of green and renewable liquid fuels, whose efficiency and selectivity are restricted by sluggish charge kinetics and unfavorable surface reaction dynamics in conversional semiconductor photocatalysts. This study proposes a surface selenation strategy on metal cocatalysts to improve the photocatalytic performance in CO 2 -to-CH 3 OH conversion. Electron microscopy observation shows the formation of a stacked structure with crystalline Rh core sandwiched between semiconductor substrate and amorphous selenated Rh (RhSe) shell after the treatment. The combination of experimental characterizations with theoretical simulations reveals that Rh core smoothens the migration of photoelectrons from light-harvesting semiconductor to RhSe shell, while the selenation of Rh shell not only reduces the rate-limiting barriers required for CH 3 OH production, but also inhibits the occurrence of side H 2 evolution. Enabled by such a design, significantly enhanced photocatalytic activities (41.2 μmol g cat -1 h-1) and selectivties (91.2%) in CH 3 OH generation are achieved by the Rh@RhSe semi-core-shell cocatalysts, 12.7 and 6.4 times as high as that of pristine Rh, respectively. Moreover, the generalized strategy can be extended to other metal cocatalysts for improved CO 2 -to-CH 3 OH transformation, which opens a new avenue for powering the future with liquid sunshine. [ABSTRACT FROM AUTHOR]

We present an optimal rate convergence analysis for a second order accurate in time, fully discrete finite difference scheme for the Cahn–Hilliard–Navier–Stokes (CHNS) system, combined with logarithmic Flory–Huggins energy potential. The numerical scheme has been recently proposed, and the positivity-preserving property of the logarithmic arguments, as well as the total energy stability, have been theoretically justified. In this paper, we rigorously prove second order convergence of the proposed numerical scheme, in both time and space. Since the CHNS is a coupled system, the standard ℓ ∞ (0 , T ; ℓ 2) ∩ ℓ 2 (0 , T ; H h 2) error estimate could not be easily derived, due to the lack of regularity to control the numerical error associated with the coupled terms. Instead, the ℓ ∞ (0 , T ; H h 1) ∩ ℓ 2 (0 , T ; H h 3) error analysis for the phase variable and the ℓ ∞ (0 , T ; ℓ 2) analysis for the velocity vector, which shares the same regularity as the energy estimate, is more suitable to pass through the nonlinear analysis for the error terms associated with the coupled physical process. Furthermore, the highly nonlinear and singular nature of the logarithmic error terms makes the convergence analysis even more challenging, since a uniform distance between the numerical solution and the singular limit values of is needed for the associated error estimate. Many highly non-standard estimates, such as a higher order asymptotic expansion of the numerical solution (up to the third order accuracy in time and fourth order in space), combined with a rough error estimate (to establish the maximum norm bound for the phase variable), as well as a refined error estimate, have to be carried out to conclude the desired convergence result. To our knowledge, it will be the first work to establish an optimal rate convergence estimate for the Cahn–Hilliard–Navier–Stokes system with a singular energy potential. [ABSTRACT FROM AUTHOR]

In high-speed rotating channels, significant compressive effects are observed, resulting in distinct flow characteristics compared to incompressible flows. This study employs a finite volume method, based on the implicit formulation, to solve for low-speed compressible laminar flow in rotating channels using an orthogonal uniform grid. The governing equations include the full Navier–Stokes equations and the energy equation. The alterations in flow within rotating channel are primarily influenced by the compressive effects of centrifugal force and the compressibility of fluid within the flow's normal section. The first effect involves a reduction in the velocity due to centrifugal force, leading to an increasing influence of the Coriolis force compared to inertial forces. This trend change aligns closely with the increase in rotation speed. The second effect arises from the increase in the rotating Mach number and the Coriolis compression, resulting in slight density differences within the cross section. Strong centrifugal forces generate significant centrifugal additional force (buoyancy force). Consequently, under the same local rotation number, the velocity profiles of the mainstream experience considerable changes. Additionally, a higher rotating Mach number significantly impacts wall shear stress, with the leading side being notably affected. For instance, at cross-sectional Ro = 0.6 and MaΩ = 2.1, the dimensionless shear stress on the leading side decreased by 13%. Furthermore, while an increase in the rotating Mach number has minimal impact on the cross-sectional secondary flow structure, changes in mainstream velocity profiles influence secondary flow intensity, resulting in an enhanced velocity peak and a shift toward the trailing side. [ABSTRACT FROM AUTHOR]

Bone-Marrow Stromal Cells (BMSCs)-derived vascular endothelial cells (VECs) is regarded as an important therapeutic strategy for spinal cord injury, disc degeneration, cerebral ischemic disease and diabetes. The change in DNA methylation level is essential for stem cell differentiation. However, the DNA methylation related mechanisms underlying the endothelial differentiation of BMSCs are not well understood. In this study, DNA methyltransferase inhibitor, 5-aza-2′-deoxycytidine (5-aza-dC) significantly elevated the endothelial markers expression (CD31/PECAM1, CD105/ENG, eNOS and VE-cadherin), as well as promoted the capacity of angiogenesis on Matrigel. The result of Alexa 488-Ac-LDL uptake assay indicated that the differentiation ratio of BMSCs into VECs was 68.7% in 5-azaz-dC induced differentiation. And then we screened differentiation inducers with altered expression patterns and DNA methylation levels in four important families (VEGF, ANG, FGF and ETS). By integrating these data, five endothelial differentiation inducers (VEGFA, ANGPT2, FGF2, FGF9 and ETS1) which were directly upregulated by 5-aza-dC and five indirect factors (FGF1, FGF3, ETS2, ETV1 and ETV4) were identified. These data suggested that 5-aza-dC is an excellent chemical molecule for BMSCs differentiation into functional VECs and also provided essential clues for DNA methylation related signaling during 5-aza-dC induced endothelial differentiation of BMSCs. [ABSTRACT FROM AUTHOR]

Developing an accelerated acceptance sampling plan (AASP) is essential to product reliability demonstration, particularly for a product designed to have high reliability and long lifetime. Because of acceleration, a decision on lot acceptance for the product can be quickly made while significantly reducing the total cost of testing. Traditionally, the parameters of an acceptance probability function used in AASP are assumed to be known in advance. However, it is often difficult, if not impossible, to determine the exact values of these parameters. On the other hand, prior information, including earlier test results and expert opinions, may be available for potential uses in planning such tests. In this paper, Bayesian designs of AASP are considered by taking full advantage of prior information to reduce the uncertainty in these important parameters so that significant testing resources (e.g., sample size and testing time) can be saved. In particular, a product with a lognormal lifetime distribution is studied, and two types of Bayesian AASPs under Type-I censoring are developed based on the product's operating characteristic (OC) curve. The first Bayesian AASP considers the risks of the producer and the consumer simultaneously, while the second one considers only the consumer's risk. The optimal sampling plans aim at minimizing the total costs of testing. The proposed AASPs are illustrated using two numerical examples. Sensitivity analysis on the selection of prior distribution is also performed to validate the robustness of the proposed Bayesian AASPs. In addition, a comparison study shows that the proposed test plans outperform the traditional AASPs with respect to the use of testing resources. [ABSTRACT FROM AUTHOR]