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Sulfur polymers, prepared by inverse vulcanization using elemental sulfur and vinylic monomers, are emerging functional materials of current research interest; however, sulfur polymers suffer from limited water solubility due to the hydrophobic nature of conventional comonomers and sulfur. Herein, the preparation of ionic liquid (IL)‐containing sulfur polymers are reported using the hydrophilic ionic liquid, 1‐allyl‐3‐vinylimidazolium chloride (AVImCl) as a comonomer. The introduction of IL significantly enhances the hydrophilicity of sulfur polymers, enabling them to dissolve in water. Benefiting from the thorough contact with aqueous mercury ions, the resultant sulfur polymer possesses high uptake capacity (436 mg g−1). After binding mercury, a coordination complex is formed and precipitated. The charged sulfur polymers gain a new application in demulsification. The polymer quickly breaks oil‐in‐water (O/W) emulsions through anion exchange between Cl− of the polymer and dodecylbenzenesulfonate (DBS−) of the surfactant. In addition, the polymer has a growth inhibitory effect against Staphylococcus aureus. The integration of IL and elemental sulfur provides a novel approach to modifying the wettability of sulfur polymers. Also, this novel water‐soluble IL‐containing sulfur polymer, with mercury capture, demulsification, and antibacterial activity, can be considered as a multifunctional material in practical water purification. [ABSTRACT FROM AUTHOR]

Objective: Gas embolism is a common complication of hysteroscopic surgery that causes serious concern among gynecologists and anesthesiologists due to the potential risk to patients. The factors influencing gas embolism in hysteroscopic surgery have been extensively studied. However, the effect of the oxygen concentration inhaled by patients on gas embolism during hysteroscopic surgery remains elusive. Therefore, we designed a double‐blind, randomized, controlled trial to determine whether different inhaled oxygen concentrations influence the occurrence of gas embolism during hysteroscopic surgery. Methods: This trial enrolled 162 adult patients undergoing elective hysteroscopic surgery who were randomly divided into three groups with inspired oxygen fractions of 30%, 50%, and 100%. Transthoracic echocardiography (four‐chamber view) was used to evaluate whether gas embolism occurred. Before the start of surgery, the four‐chamber view was continuously monitored. Results: The number of gas embolisms in the 30%, 50%, and 100% groups was 36 (69.2%), 30 (55.6%), and 24 (44.4%), respectively. The incidence of gas embolism gradually decreased with increasing inhaled oxygen concentration (P = 0.031). Conclusion: In hysteroscopic surgery, a higher oxygen concentration inhaled by patients may reduce the incidence of gas embolism, indicating that a higher inhaled oxygen concentration, especially 100%, could be recommended for patients during hysteroscopic surgery. Trial Registration: Chinese Clinical Trial Registry (https://www.chictr.org.cn/showproj.html?proj=53779, Registration number: ChiCTR2000033202). Synopsis: In hysteroscopic surgery, a higher oxygen concentration inhaled by patients may reduce the incidence of gas embolism. [ABSTRACT FROM AUTHOR]

Frequency regulation of wind turbines can improve the stability of the power system. However, it would cause generator torque fluctuation, increasing the risk of fatigue load. Previous research works were restricted to inertial and droop responses. Less attention has been paid to striking a balance between frequency regulation and fatigue load. To overcome these, a hybrid control strategy is proposed to consider both frequency response characteristic and fatigue load mitigation. First, a small signal linearization model is built to reveal the impact of the correlation mechanism of frequency regulation on drive train torque load. Second, a multivariable cost function is constructed to optimize the proportional integral (PI) controller, which combines the total fluctuation with the dispersion of the fatigue load and frequency. Then, a hybrid controller based on PI control optimized by particle swarm optimization algorithm and active disturbance rejection control is designed to restrain rapid frequency changes as well as fatigue torque fluctuation simultaneously. Several experiments are performed to verify the significance of the proposed method under different scenarios. Compared with the existing methods, the proposed hybrid control exhibits superiority in improving frequency response and fatigue load mitigation. [ABSTRACT FROM AUTHOR]

Purpose: Primary central nervous system post-transplantation lymphoproliferative disorder (PCNS-PTLD) is a rare but serious complication of hematopoietic stem cell transplantation (HSCT) in patients with severe β-thalassemia. This study aimed to assess the clinical presentation, pathological characteristics, neuroimaging findings, and treatment strategies in patients with β-thalassemia who developed PCNS-PTLD and to compare a case series from our transplant center to reported cases from literature. Methods: We retrospectively reviewed our hospital database and identified four cases of pathologically confirmed PCNS-PTLD without a history of systemic PTLD in patients with severe β-thalassemia after HSCT. We also performed a relevant literature review on PCNS-PTLD. Results: The median time from transplantation to diagnosis of PCNS-PTLD was 5.5 months. Intracerebral lesions were usually multiple involving both supratentorial and infratentorial regions with homogeneous or rim enhancement. All patients had pathologically confirmed PCNS-PTLD with three patients having diffuse large B-cell lymphoma and the fourth patient having plasmacytic hyperplasia. There was low response to treatment with a median survival of 83 days. Conclusion: PCNS-PTLD should be considered in the differential diagnosis of patients with β-thalassemia who had an intracranial lesion on neuroimaging after HSCT. Critical relevance statement: This case series with a comprehensive review of neuroimaging and clinical characteristics of children with primary central nervous system post-transplantation lymphoproliferative disorder should advance our understanding and improve management of this rare yet severe complication following transplant for β-thalassemia. Key points: • We assessed clinical presentation, treatment strategies, and neuroimaging characteristics of PCNS-PTLD in patients with β-thalassemia after transplantation. • Patients with β-thalassemia may have post-transplantation lymphoproliferative disorder presenting as brain lesions on neuroimaging. • Neuroimaging findings of the brain lesions are helpful for prompt diagnosis and proper management. [ABSTRACT FROM AUTHOR]

Numerical simulations of high-speed compressible flows remain challenging in engineering as the appearance of shock waves poses difficulties for high-resolution schemes as well as explicit large eddy simulation methods. Therefore, in this work, we propose a practical numerical solver for simulations of shock-vortex and shock-turbulence problems with the implicit large eddy simulation approach and newly developed low-dissipative schemes. In order to handle the multi-scale raised in the shock-vortex and shock-turbulence problems, it is required that the flow solver can simultaneously solve the large-scale flow structures such as shock waves with numerical oscillation-free, the resolvable flow structures above the grid scale with low-dissipation, and the under-resolve isotropic sub-grid scale with numerical stability. To this end, a low-dissipative, structure-preserving scheme with rigorously adjusted numerical dissipation is employed in the proposed solver. The structure-preserving property of this scheme can ensure that the large-scale structure is solved without numerical oscillations and the low-dissipative property of this scheme can produce high-resolution results for the resolvable flow scales. Moreover, the sub-grid scale is solved and stabilized by the inherent numerical dissipation in the shock-capturing scheme. The proposed numerical solver is then applied to simulate a wide range of shock-vortex and shock-turbulence interaction problems including supersonic planar jets, transonic flows past a deep cavity and impingement of a supersonic jet on a cone mounted on a flat plate. A comparison is also made with the solver using conventional total variation diminishing schemes. The numerical results of the supersonic planar jet have demonstrated that the proposed solver can resolve the small-scale structure such as Kelvin–Helmholtz instability involved in shock and shear layer with high-resolution. Through the results of transonic flow past a deep cavity and comparisons with the experimental data, it is verified that the proposed solver can reproduce the turbulence statistical data. Furthermore, the proposed solver resolves the complex turbulent fluid mechanical phenomena in the impingement of a supersonic jet on a cone, which demonstrates the proposed solver can robustly handle irregular geometry. The proposed solver also enjoys simplicity without using the explicit sub-grid scale model and involving the complexity of very high-order schemes. Thus, this work provides an accurate and practical numerical solver for shock-vortex and shock-turbulence problems in high-speed flows. • An accurate and practical solver for shock-vortex and shock-turbulence problems. • Resolvable flow scale is solved by structure-preserving ROUND schemes. • Sub-grid scale is modeled with inherent numerical dissipation. • Challenging case such as impingement of a supersonic jet on a cone is simulated. • The proposed solver enjoys simplicity and can handle irregular geometry. [ABSTRACT FROM AUTHOR]

In this article, we report the synthesis of a MOF containing multiple C＝C bonds geometrical features by adjusting the reactant ratio of the synthetic system. The photochemical addition studies revealed that the ligand 1,4-bis[2-(4-pyridyl)ethenyl]benzene can undergo photoisomerization under UV irradiation, and the angle between the C＝C bonds can be changed by about 85°, so that the C＝C pairs that do not conform to Schmidt's rule can be transformed into the conforming state, and then the 2 + 2 photoaddition can occur. We found that the angle range suitable for photoaddition includes not only the 0–15° range, but also the potential 85 ± 15° range. Furthermore, it is not the C＝C pair that best conforms to Schmidt's rule that gives priority to the photoaddition, but the one that enables the lowest total energy in the crystal to occur. [ABSTRACT FROM AUTHOR]

Large eddy simulation (LES) has the potential to predict turbulent combustion phenomena in modern practical combustors. As errors from sub-grid models may be comparable to the numerical errors in the LES approach, mitigating the impact of the numerical errors is as important as constructing accurate sub-grid models. Therefore, a low-dissipative, structure-preserving ROUND (Reconstruction Operators on Unified Normalized-variable Diagram) scheme is tested for the LES of reacting flows in this study. The high efficiency of this scheme is demonstrated by evaluating its accuracy, central processing unit cost, and structure-preserving property by simulating the convection–diffusion process of a passive scalar. Simulations of two bluff body stabilized flames are studied using this scheme. For low turbulence intensity, the current scheme improves the numerical resolution of the instantaneous and averaged flow fields. The prediction of flow statistics is also improved by the ROUND schemes compared to the conventional schemes. Moreover, the ROUND schemes preserve the axisymmetry of the averaged flow better than the conventional schemes for the cases investigated here. For the high turbulence intensity case, the ROUND scheme avoids nonphysical numerical oscillations. The flow and flame statistics obtained using this scheme compare well with measurements. Therefore, this work demonstrates the advantages of using ROUND schemes for LES of reacting flows. [ABSTRACT FROM AUTHOR]

This paper collected 22 cases of explosion accidents in laboratories in China in the past 10 years, analyzed the causes of the accidents, and put forward measures of preventing and mitigating the hazards of explosion accidents by identifying the explosion hazards in laboratories, assessing the explosion risks, minimizing the explosion hazards, and preparing for possible explosion accidents. Specific preventive measures are the DATS principles: keep the Distance as far as possible, use the minimum Amount of explosives, shorten the residence Time, and use appropriate Shielding. [ABSTRACT FROM AUTHOR]

A Mach 1.5 non-reactive flow in a cavity-stabilized combustor of a model scramjet is studied via a direct-numerical simulation approach, and the analysis is focused on the interaction among boundary layer, free shear-layer above the cavity and shock wave. It is found that the impingement of the free shear-layer on the aft wall of the cavity leads to strong turbulence kinetic energy, high local pressure, and a fan of compression waves. The compression waves evolve into an oblique shock, which reflects between the upper and lower walls and interacts with the boundary layers attached to the two walls. The analysis of the turbulence production reveals that the amplification of turbulence in the core of the shear-layer and around the reattachment point is mainly due to the shear production, but the deceleration production mechanism presents a significant impact in the regions above the aft wall of the cavity and around the shock interaction points. The very low frequency commonly observed in shock wave/boundary layer interactions is not observed in the present research, which might be due to the low Reynolds number of the studied case. [ABSTRACT FROM AUTHOR]

Whole genome sequencing for generating SNP data is increasingly used in population genetic studies. However, obtaining genomes for massive numbers of samples is still not within the budgets of many researchers. It is thus imperative to select an appropriate reference genome and sequencing depth to ensure the accuracy of the results for a specific research question, while balancing cost and feasibility. To evaluate the effect of the choice of the reference genome and sequencing depth on downstream analyses, we used five confamilial reference genomes of variable relatedness and three levels of sequencing depth (3.5×, 7.5× and 12×) in a population genomic study on two caddisfly species: Himalopsyche digitata and H. tibetana. Using these 30 datasets (five reference genomes × three depths × two target species), we estimated population genetic indices (inbreeding coefficient, nucleotide diversity, pairwise FST, and genome‐wide distribution of FST) based on variants and population structure (PCA and admixture) based on genotype likelihood estimates. The results showed that both distantly related reference genomes and lower sequencing depth lead to degradation of resolution. In addition, choosing a more closely related reference genome may significantly remedy the defects caused by low depth. Therefore, we conclude that population genetic studies would benefit from closely related reference genomes, especially as the costs of obtaining a high‐quality reference genome continue to decrease. However, to determine a cost‐efficient strategy for a specific population genomic study, a trade‐off between reference genome relatedness and sequencing depth can be considered. [ABSTRACT FROM AUTHOR]

• Accurate, practical and robust numerical solvers for high-speed single- and multi- material flow simulations. • New 3D advection schemes with improved resolution across discontinuities. • Implementation with OpenFoam for wide industrial applications. Although the accuracy and the robustness of discretized schemes solving hyperbolic systems have been greatly improved over the last two decades, devising a low-dissipative and non-oscillatory method remains a challenge. Especially, it is algorithmically complicated and computationally expensive to extend and apply high-resolution non-oscillatory schemes to 3D hybrid unstructured grids. Therefore, in this work we develop accurate, practical, and robust 3D hybrid unstructured OpenFoam solvers which can be applied in wide industrial applications. Different from existing 3D high order numerical solvers of which reconstruction schemes are based on polynomials of high degree, the proposed 3D scheme employs a polynomial function and a hyperbolic tangent basis function as two candidates for reconstruction functions. The MUSCL (Monotone Upstream-centered Schemes for Conservation law) scheme with the MLP (Multi-dimensional Limiting Process) slope limiter is adopted as the polynomial function. The multi-dimensional THINC (Tangent of Hyperbola for INterface Capturing) function with quadratic surface representation and Gaussian quadrature, so-called THINC/QQ, is used as the non-polynomial reconstruction candidate. With these reconstruction candidates, a multi-stage boundary variation diminishing (BVD) algorithm which significantly minimizes numerical dissipation is designed on 3D unstructured grids to select the final reconstruction function. With this accurate and robust reconstruction scheme, then we developed new solvers for simulating inviscid high speed compressible single-phase flow and two-phase flow via the implementation of the proposed scheme and algorithm into the open-source computational fluid dynamics (CFD) software, OpenFOAM. The solver with the proposed low-dissipative scheme, named as EulerEquationFoam-M-TQ-BVD, is constructed with the density-based solver for inviscid high speed compressible flow simulations. To simulate compressible multi-material flow with moving material interfaces, a solver named as FiveEquationFoam-M-TQ-BVD is developed based on mechanical-equilibrium diffusive interface model and MieGrüneisen equation of state. The performance of new solvers is evaluated through wide range benchmark tests and are compared with existing high order schemes such as the third-order WENO (Weighted Essentially Non-Oscillatory) scheme. The new solvers produce superior solution across critical points, contact discontinuities and material interfaces. Moreover, in comparison with WENO schemes, the proposed solver enjoys algorithmic simplicity and greater flexibility in 3D hybrid unstructured grids. Thus, this work provides accurate, practical and robust numerical solvers for high speed compressible single- and multi-material flow simulations. [ABSTRACT FROM AUTHOR]

Power electronic equipment regulated by International Thermonuclear Experimental Reactor (ITER) must pass the relevant steady-state magnetic field immunity test. The main body of magnetic field immunity test is magnetic field generator coil. Through mathematical derivation in this article, the magnetic field calculation formulas of four-coil configuration under ideal and actual models are obtained. The traditional method of magnetic field performance calculation is compared with the general formula method under the ideal model. A global parameter optimization method based on Lagrange Multiplier by Karush–Kuhn–Tucker (KKT) conditions is proposed to obtain the coil parameters of high-uniformity magnetic field. The magnetic field distribution in the uniform zone is revealed by the finite-element method. The model analysis is proven to be correct and effective by experimental results. The research of this article provides a practical scheme for the coil design with high magnetic field and high-quality uniformity. [ABSTRACT FROM AUTHOR]

Summary: Art painting is a very important major in China's education system. Under the background of the new era, the country vigorously promotes the modernization of education and the development of intelligence. Many subjects of teaching have been more mature and carried out intelligent teaching based on virtual reality technology. But throughout the art painting profession, the research on this aspect is almost blank. The main reason is that there are deep academic barriers between art painting and computer science. Therefore, this paper puts forward the application research of multi‐source information art painting fusion interactive 3D dynamic scene virtual reality technology. This paper deeply analyzes the needs of art painting and its teaching reform and believes that the existing virtual reality technology cannot adapt to the teaching environment of art painting. In view of the possible inaccurate calculation and other problems, this paper puts forward the optimization scheme. The core of the scheme is to use the information integration advantages of multi‐source information fusion to provide more comprehensive and complete object information for 3D modeling of virtual reality technology, so as to improve the imaging quality of virtual reality technology. In order to meet the requirement of high precision, the calculation method is optimized, the calculation steps are simplified, and the sensor selection is optimized again. This paper introduces the design principle and operation steps of the optimization method in detail. In order to further verify the actual effect of this method, comparative analysis method is used to test the comprehensive performance. In order to ensure the test quality, the median filtering algorithm and fuzzy algorithm are compared. Through the analysis and comparison of the data, the optimization method in this paper greatly improves the accuracy of calculation and the comprehensive performance is improved. [ABSTRACT FROM AUTHOR]

With the Group of 20 (G20) incorporating climate actions into recovery plans, the post-COVID period presents a unique opportunity for green economy. Nevertheless, reporting on future short-term fossil carbon emissions has been constrained due to delays in parameterizing complex energy models. This study aimed to develop a novel approach, utilizing machine learning algorithms, to estimate fossil carbon dioxide (CO 2) emissions by 2030 without the need for intricate energy modeling. Our analysis revealed that the machine learning approach performed effectively, and the post-pandemic CO 2 emissions are predicted to be 10.1 %–17.7 % lower than the pre-pandemic projections. However, this reduction still falls significantly short of the abatement requirement for the 1.5 °C Paris Agreement climate target. Results underscores the urgency for governments to acknowledge the "kick-start" effect of COVID-19 and expedite technology upgrades as well as the deployment of clean infrastructure. This study offers a novel machine-learning perspective on post-pandemic green recovery, future research could expand the spatial scope and enhance the reliability of simulations as more data becomes available. [Display omitted] [ABSTRACT FROM AUTHOR]

To overcome the poor mechanical performance of methyltrimethoxysilane (MTMS) aerogels and the low thermal stability of polyvinyl alcohol (PVA), the PVA/MTMS aerogel composites (PMAC) were successfully prepared through a facile impregnation process. It finds that the PVA concentration has a great influence on the physicochemical properties of the PMAC, which has been investigated in detail. It further turns out that the density (0.081 ~ 0.152 g/cm3) increases linearly along with the PVA concentration, while the thermal conductivity (32.9 ~ 51.7 mW/m/K) increases monotonously first and then keeps almost unchanged. The hydrophilicity of PMAC can be tailored by adjusting the PVA concentration. Compared with the pure MTMS aerogel and PVA, the thermal analysis reveals that the PMAC shows an improved thermal stability. Although the physical combination is verified between the MTMS aerogel and PVA, the mechanical performance of the PMAC is still significantly enhanced with the Young's modulus and compressive strength reaching up to 20.35 MPa and 970.33 kPa, respectively. All these results suggest that the introduction of PVA into MTMS aerogel is feasible and effective for acquiring better performance for the aerogel composites, which contributes to extending their potential applications. [ABSTRACT FROM AUTHOR]

The Ni‐catalyzed decarbonylative borylation of (hetero)aryl carboxylic acids with B2cat2 has been achieved without recourse to any additives. This Ni‐catalyzed method exhibits a broad substrate scope covering poorly reactive non‐ortho‐substituted (hetero)aryl carboxylic acids, and tolerates diverse functional groups including some of the groups active to Ni0 catalysts. The key to achieve this decarbonylative borylation reaction is the choice of B2cat2 as a coupling partner that not only acts as a borylating reagent, but also chemoselectively activates aryl carboxylic acids towards oxidative addition of their C(acyl)−O bond to Ni0 catalyst via the formation of acyloxyboron compounds. A combination of experimental and computational studies reveals a detailed plausible mechanism for this reaction system, which involves a hitherto unknown concerted decarbonylation and reductive elimination step that generates the aryl boronic ester product. This mode of boron‐promoted carboxylic acid activation is also applicable to other types of reactions. [ABSTRACT FROM AUTHOR]

The Ni‐catalyzed decarbonylative borylation of (hetero)aryl carboxylic acids with B2cat2 has been achieved without recourse to any additives. This Ni‐catalyzed method exhibits a broad substrate scope covering poorly reactive non‐ortho‐substituted (hetero)aryl carboxylic acids, and tolerates diverse functional groups including some of the groups active to Ni0 catalysts. The key to achieve this decarbonylative borylation reaction is the choice of B2cat2 as a coupling partner that not only acts as a borylating reagent, but also chemoselectively activates aryl carboxylic acids towards oxidative addition of their C(acyl)−O bond to Ni0 catalyst via the formation of acyloxyboron compounds. A combination of experimental and computational studies reveals a detailed plausible mechanism for this reaction system, which involves a hitherto unknown concerted decarbonylation and reductive elimination step that generates the aryl boronic ester product. This mode of boron‐promoted carboxylic acid activation is also applicable to other types of reactions. [ABSTRACT FROM AUTHOR]

Hainan is located at the southernmost tip of China, since ancient times it has always occupied an important position on the Silk Road. Hainan culture is dominated by minority and marine cultures and has a rich intangible cultural heritage. Hainan has always been committed to the development and utilization of its wide cultural heritage, and the development direction is mainly based on live display and folk activities. In May 2020, the Chinese government announced the establishment of the Hainan Free Trade Port Policy and System, the establishment of a Hainan International Free Trade Zone, and the development of tourism, modern services, and high-tech industry. All these put forward higher requirements for the protection of Hainan's cultural heritage, not just traditional ways to protect and promote, but also to use the dividends of current scientific and technological development to keep up with the times to protect and promote. The integration of digital technology will be the development direction of cultural heritage and intangible cultural heritage. This paper enumerates and analyzes other cases and academic directions of intangible cultural heritage, combined with the present situation of intangible cultural heritage in Hainan. It also analyzes the predicament of handiwork inheritance in Hainan intangible cultural heritage, expounds the structure, humanistic connotation, and construction skills of Li nationality ship house, and summarizes the role of a novel deep learning convolutional neural network- (CNN-) based virtual reality framework of intangible cultural heritage conservation in promoting the intangible cultural heritage of traditional skills. It also puts forward the scheme and heritage conservation virtual reality content construction and provides the process of building a virtual reality platform for the intangible cultural heritage of ship-shaped houses, which as an example can be used as a reference for intangible cultural heritage researchers in other areas. At the same time, it fills the gap for the artificial intelligence-based digitization of the intangible cultural heritage. [ABSTRACT FROM AUTHOR]

• The prevalence of IGD symptoms is 1.78 % among Chinese adolescents. • Excessive online gaming not only contributes to psychological distress of adolescents, but also increase the level of aggressive behavior. • Apart from male sex and younger age, severe IGD symptoms and psychological distress are the most important predictors of the development of aggressive behavior. The present study aimed to investigate the current situation of internet gaming disorder (IGD) in Chinese adolescents and explore the impact of IGD-related factors on adolescent aggression. We hypothesized that IGD symptoms in adolescents would be associated with aggressive behavior and that risk factors for IGD symptoms could increase the aggressive tendencies of adolescents. To verify the above hypothesis, a cross-sectional survey of junior and senior high school students from southern, southwestern, central, and eastern China was conducted. A total of 9306 valid questionnaires were collected. The results showed that the prevalence of IGD symptoms was 1.78 % among Chinese adolescents. The adolescents in the disordered gamer group had the most severe IGD symptoms, with the highest levels of psychological distress and aggression. Interestingly, adolescents in the casual gamer group had the lowest psychological distress and aggression scores. Linear regression analysis further showed that higher levels of aggression were significantly associated with male sex, younger age, more severe psychological distress and IGD symptoms, and more violent game exposure. Our results suggested that excessive online gaming not only contributes to psychological distress in adolescents but also increases their levels of aggressive behavior. Apart from male sex and younger age, severe IGD symptoms and psychological distress are the most important predictors of the development of aggressive behavior. [ABSTRACT FROM AUTHOR]

The trend towards multifunctionality and integrating electronic devices has led to the exploration of Y-type hexaferrite with excellent magnetic and dielectric properties. The Y-type hexaferrite BaSrCo 2 Fe 11-x Cr x AlO 22 (0.0 ≤ x ≤ 0.5, with step of 0.1) ceramics have been prepared by conventional solid state reaction route. The phase structure, microscopic morphology, magnetic and dielectric properties of Y-type hexaferrite with chromium substitution are studied in detail. The analysis of XRD, SEM and EDS reveals that the lattice parameters and grain size decrease with the increase of Cr content. XPS results show the coexistence of Fe2+ and Fe3+. All samples exhibit well-defined ferromagnetic hysteresis loops at room temperature and the Cr3+ doping enhances the saturation magnetization and coercivity. The dielectric constants for all samples are found in the range of 10–15 and the dielectric loss is less than 0.02 at high frequency. The resistivity demonstrates that the samples possess high insulating nature with all above 2 × 109 Ω·cm, with a maximum value of 9.5 × 109 Ω·cm for x = 0.2. These results reveal that Cr3+ doped Y type hexaferrite could have potential applications in multifunctional electronic devices. [ABSTRACT FROM AUTHOR]

A novel compound, 3,7-dichloro-N-(2,6-diethylphenyl)-N-(2-propoxyethyl)quinoline-8-carboxamide was synthesized by splicing together a chloro-substituted quinoline moiety found in quinclorac (a selective herbicide) and a substituted amide moiety found in pretilachlor (another selective herbicide) using the active substructure splicing method. The chemical structure of this compound was characterized by 1H, 13C NMR, FTIR, high-resolution mass spectra and X-ray diffraction analysis. Pesticide potency (herbicidal and fungicidal activity) of this compound was evaluated. This compound displayed excellent control efficiency against Echinochloa crusgalli and also showed good fungicidal in vitro activity against Phytophthora capsici, Phytophthora sojae, and Phytophthora infestans. [ABSTRACT FROM AUTHOR]

The fifth version of the Hypertext Markup Language (HTML) standard is widely adopted in the diverse landscape of browser vendors and their continuously upgrading releases. One primary feature of HTML5 is native multimedia playback. The browsers’ native implementations of multimedia support bring lots of benefits such as improved security but require thorough testing, especially on the web page of complex factor combinations according to our manual checking of publicly visible existing tests. This article employs the combinatorial testing technique to trigger failure-inducing factor combinations effectively and to locate them, guided by some extracted properties that cover browsers’ major workflow of processing multimedia. Results are analyzed to give objective suggestions for browser developers to cast light on the places that implementation enhancement could be made, and for web developers to avoid undesirable effects. [ABSTRACT FROM AUTHOR]

Antibiotics contribute a lot to human beings and can kill bacteria effectively. However, more and more studies show that antibiotics can disturb the intestinal microbial community. It has been widely reported that oral antibiotics can reduce the diversity of intestinal microflora, but the effect of intramuscular injection on intestinal microflora is less studied. In this study, we sequenced the intestinal microflora of mice treated with tetracycline by 16SrRNA method, and found that intramuscular injection of tetracycline (TET) can also reduce the intestinal microbial richness of mice. In addition, the results showed that within a certain range (3 mg), with the increase of TET injection concentration, the wind of intestinal microflora in mice decreased significantly. When the injection concentration reached saturation, although the amount of TET injection was increased, the degree of intestinal flora affected was not increased. The results showed that the degree of diversity decrease was in direct proportion to the amount of tetracycline injection in the saturated concentration, but not positively related to the high amount of TET injection after exceeding the saturated concentration. [ABSTRACT FROM AUTHOR]

Medium-chain fatty acids (C6–C10) have attracted much attention recently for their unique properties compared to their long-chain counterparts, including low melting points and relatively higher carbon conversion yield. Thioesterase enzymes, which can catalyze the hydrolysis of acyl-ACP (acyl carrier protein) to release free fatty acids (FAs), regulate both overall FA yields and acyl chain length distributions in bacterial and yeast fermentation cultures. These enzymes typically prefer longer chain substrates. Herein, seeking to increase bacterial production of MCFAs, we conducted structure-guided mutational screening of multiple residues in the substrate-binding pocket of the E. coli thioesterase enzyme 'TesA. Confirming our hypothesis that enhancing substrate selectivity for medium-chain acyl substrates would promote overall MCFA production, we found that replacement of residues lining the bottom of the pocket with more hydrophobic residues strongly promoted the C8 substrate selectivity of 'TesA. Specifically, two rounds of saturation mutagenesis led to the identification of the 'TesARD−2 variant that exhibited a 133-fold increase in selectivity for the C8-ACP substrate as compared to C16-ACP substrate. Moreover, the recombinant expression of this variant in an E. coli strain with a blocked β -oxidation pathway led to a 1030% increase in the in vivo octanoic acid (C8) production titer. When this strain was fermented in a 5-L fed-batch bioreactor, it produced 2.7 g/L of free C8 (45%, molar fraction) and 7.9 g/L of total free FAs, which is the highest-to-date free C8 titer to date reported using the E. coli type II fatty acid synthetic pathway. Thus, reshaping the substrate binding pocket of a bacterial thioesterase enzyme by manipulating the hydrophobicity of multiple residues altered the substrate selectivity and therefore fatty acid product distributions in cells. Our study demonstrates the relevance of this strategy for increasing titers of industrially attractive MCFAs as fermentation products. • Semi-rational design of 'TesA thioesterase was performed to reshape the acyl binding pocket. • The best variant exhibits a 133-fold increase in selectivity for C8-ACP as compared to C16-ACP substrate. • The highest octanoic acid (2.7 g/L) titer was achieved in E. coli type II fatty acid synthetic pathway. [ABSTRACT FROM AUTHOR]

• A numerical model for simulation of sub-critical cryogenic jets is constructed. • The proposed model is able to solve multi-physics processes involving moving interface, phase transition and combustion. • Hybrid thermodynamic closure is proposed for the mixture of liquid and reactive species under the sub-critical condition. • A low dissipation Riemann solver and a homogenous reconstruction strategy are adopted. In order to simulate cryogenic H 2 − O 2 jets under subcritical condition, a numerical model is constructed to solve compressible reactive multi-component flows which involve complex multi-physics processes such as moving material interfaces, shock waves, phase transition and combustion. The liquid and reactive gaseous mixture are described by a homogeneous mixture model with diffusion transport for heat, momentum and species. A hybrid thermodynamic closure strategy is proposed to construct an equation of state (EOS) for the mixture. The phase transition process is modeled by a recent fast relaxation method which gradually reaches the thermo-chemical equilibrium without iterative process. A simplified transport model is also implemented to ensure the accurate behavior in the limit of pure fluids and maintain computational efficiency. Last, a 12-step chemistry model is included to account for hydrogen combustion. Then the developed numerical model is solved with the finite volume method where a low dissipation AUSM (advection upstream splitting method) Riemann solver is extended for multi-component flows. A homogeneous reconstruction strategy compatible with the homogeneous mixture model is adopted to prevent numerical oscillations across material interfaces. Having included these elements, the model is validated on a number of canonical configurations, first for multiphase flows, and second for reactive flows. These tests allow recovery of the expected behavior in both the multiphase and reactive limits, and the model capability is further demonstrated on a 2D burning cryogenic H 2 − O 2 jet, in a configuration reminiscent of rocket engine ignition. [ABSTRACT FROM AUTHOR]

• Implicit large eddy simulation of compressible turbulence is performed with newly proposed PnTm-BVD schemes. • More accurate predictions of the turbulence evolution are obtained compared with WENO schemes. • Faithful solutions to capture discontinuities are realized with BVD algorithm. • The superiority of PnTm-BVD is more notable in high wave-number region. Implicit large eddy simulation (ILES) of compressible turbulence with shock capturing schemes requires wide investigations and numerical experiments. In this study, a newly proposed P n T m − BVD (polynomial of n -degree and THINC function of m -level reconstruction based on BVD algorithm) shock capturing scheme is introduced to simulate compressible turbulence flow with ILES. The new scheme is designed by employing high-order linear-weight polynomials and THINC (Tangent of Hyperbola for INterface Capturing) functions with adaptive steepness as the reconstruction candidates. The final reconstruction function in each cell is determined with a multi-stage BVD (Boundary Variation Diminishing) algorithm so as to effectively control numerical oscillation and dissipation. Numerical tests involving shock waves and broadband turbulence are conducted in comparison with WENO (Weighted Essentially Non-oscillatory) schemes which are widely used in ILES. The results demonstrate performing ILES with P n T m − BVD scheme is able to obtain higher resolution and more faithful results than WENO does. Importantly, the superiority of P n T m − BVD becomes more notable in high wave-number region. Thus this paper provides and verifies a new scheme which is promising in providing high-resolution results for real-case ILES of compressible turbulence flow. [ABSTRACT FROM AUTHOR]

We proposed a novel multi-moment finite volume method (MMFVM) to compute compressible viscous flows on arbitrary unstructured grids. Unlike the previous volume-average/point-value multi-moment (VPM) method (Xie et al. 2014 [60]), the present method, so-called VPM-Ex (VPM with extended-stencil reconstruction), formulates novel spatial reconstructions with substantially improved robustness and accuracy for both smooth and discontinuous solutions. Our efforts in this work have brought at least the following new features to the numerical formulation: 1) a more robust and accurate spatial reconstruction based on the stencil of all immediately adjacent cells that supports higher-order limiting projection; 2) two different options for both explicit and implicit reconstructions; 3) a simplified and more accurate formulation for point-value. In addition, we have proposed a smoothness-adaptive fitting (SAF) method for limiting projection to improve the solution quality for discontinuities. The resulting reconstruction method that combines VPM-Ex scheme with SAF-based limiting projection schemes is able to attain 3rd-order accuracy for smooth solution, and non-oscillatory and less-dissipative numerical results for discontinuous solution on unstructured grids of different types of elements. The numerical method has been extensively verified by various benchmark tests for scalar conservation equation, Euler equations and Navier–Stokes equations in 2 and 3 dimensions. The numerical results substantiate that the present method provides a novel numerical formulation of great practical significance to accurately resolve both continuous and discontinuous solutions. • Novel high-order VPM (volume-average/point-value multi-moment) method for arbitrary unstructured grids. • Sophisticated WENO (weighted essentially non-oscillatory) limiting process for suppressing the numerical oscillations. • Low-dissipative SAF (smoothness adaptive fitting) scheme for high-fidelity reconstruction of discontinuous solutions. • Verified solution quality on smooth and non-smooth solutions for various flow problems. [ABSTRACT FROM AUTHOR]

Abstract A novel 5th-order shock capturing scheme is presented in this paper. The scheme, so-called P 4 T 2 − BVD (polynomial of 4-degree and THINC function of 2-level reconstruction based on BVD algorithm), is formulated as a two-stage spatial reconstruction scheme following the BVD (Boundary Variation Diminishing) principle that minimizes the jumps of the reconstructed values at cell boundaries. In the P 4 T 2 − BVD scheme, polynomial of degree four and THINC (Tangent of Hyperbola for INterface Capturing) functions with two-level steepness are used as the candidate reconstruction functions. The final reconstruction function is selected through the two-stage BVD algorithm so as to effectively control both numerical oscillation and dissipation. Spectral analysis and numerical verifications show that the P 4 T 2 − BVD scheme possesses the following desirable properties: 1) it effectively suppresses spurious numerical oscillation in the presence of strong shock or discontinuity; 2) it substantially reduces numerical dissipation errors; 3) it automatically retrieves the underlying linear 5th-order upwind scheme for smooth solution over all wave numbers; 4) it is able to resolve both smooth and discontinuous flow structures of all scales with substantially improved solution quality in comparison to other existing methods; and 5) it produces accurate solutions in long term computation. P 4 T 2 − BVD , as well as the underlying idea presented in this paper, provides an innovative and practical approach to design high-fidelity numerical schemes for compressible flows involving strong discontinuities and flow structures of wide range scales. Highlights • An innovative fifth-order shock capturing scheme is proposed. • Low-dissipation linear scheme is retrieved for smooth solution over all wave numbers. • Discontinuous and smooth solution of wide-band scales are simultaneously solved with high accuracy. • The free-mode solutions are faithfully maintained in long term computation. [ABSTRACT FROM AUTHOR]

Carboxyl-functionalized carbon nanotubes (CNTs-COOH) and the amine-functionalized carbon nanotubes (CNTs-NH 2) were incorporated into the surface sizing agent of carbon fibers respectively, for modifying the interface between the fibers and the matrix. Experimental analyses of the interfacial shear strength, flexural properties, and inter-laminar shear strength revealed the beneficial effects of the CNTs-COOH and negative impacts of the CNTs-NH 2 on the interfacial and mechanical properties of the resulting composites. These results were contrary to the effects of CNTs doped into the epoxy matrix of composites. Furthermore, a molecular dynamics simulations were performed to explore the mechanism of these performances from the viewpoint of the molecular structure, revealing that the interface between the CNT-sized carbon fibers and the epoxy was driven by multiple factors, including the CNT-epoxy interfacial binding energy (IBE), the packing density of the molecular chains, and the steric hindrance of the functionalized CNTs. According to these analyses, two kinds of functionalized CNTs showed different effects at the interface between carbon fiber and resin: the CNTs-COOH on the surface of the carbon fiber tightly bonded to the epoxy and provided effective load transfer between the matrix and fibers, whereas the agglomeration of the CNTs-NH 2 , the lower IBE between the CNTs-NH 2 and the epoxy resin, and the steric hindrance produced by amine functional groups of the CNTs-NH 2 , resulting in hardly inhibiting the crack growth of the matrix under stress. Image 1 [ABSTRACT FROM AUTHOR]

This study proposes a new formulation for the Harten, Lax, and van Leer (HLL) type Riemann solver which is capable of solving contact discontinuities accurately but with robustness for strong shock. It is well known that the original HLL, which has incomplete wave structures, is too dissipative to capture contact discontinuities accurately. On the other side, contact-capturing approximate Riemann solvers such as HLL with Contact (HLLC) usually suffer from spurious solutions, also called carbuncle phenomenon, for strong shock. In this work, a new accurate and robust HLL-type formulation, the so-called HLL-BVD (HLL Riemann solver with boundary variation diminishing) is proposed by modifying the original HLL with the BVD algorithm. Instead of explicitly recovering the complete wave structures like the way of HLLC, the proposed method restores the missing contact with a jump-like function. The capability of solving contact discontinuities is further improved by minimizing the inherent dissipation term in HLL. Without modifying the original incomplete wave structures of HLL, the robustness for strong shock has been reserved. Thus, the proposed method is free from the shock instability problem. The accuracy and robustness of the new method are demonstrated through solving several one- and two-dimensional tests. Results indicate that the new formulation based on the two-wave HLL-type Riemann solver is not only capable of capturing contact waves more accurately than the original HLL or HLLC but, most importantly, is free form carbuncle instability for strong shock. [ABSTRACT FROM AUTHOR]

Abstract The recent discoveries of lead-free halide perovskites have come into notice as promising photovoltaic materials due to their high solar-to-electrical efficiency conversion. However, these perovskites suffer from large effective masses, wide band gap and affected photovoltaic performance. It is well known that it is an effective means to overcome the above shortcomings by changing the metallic ion concentration and position for the inorganic perovskite. Herein, we study the geometrical, electronic, and optical properties of RbGe 1-x Sn x I 3 with various compositions of metal atoms by performing the Density Functional Theory (DFT). Besides, we systematically investigate how the doping positions of stannum (Sn) atoms affect the electronic structure by taking mixed metal RbGe 0.50 Sn 0.50 I 3 compound as an example. The results show that RbGe 1-x Sn x I 3 exhibits the semiconducting property with the tunable direct band gaps by changing its proportions. Compared to other two doping positions in the perovskite RbGe 0.50 Sn 0.50 I 3 , the configuration with Sn atom at equator plane has better mobility of electron and optical absorption properties. Our works demonstrate that the modification of metal concentration and position will modulate the optoelectronic performance and photovoltaic properties of mixed metal perovskites. Highlights • The RbGe 1-x Sn x I 3 exhibits the modulation of their direct band gaps by varying the proportions. • The RbGe 0.50 Sn 0.50 I 3 has more superior transport and optical properties with Sn atom doping at equator plane. • The photovoltaic properties can be tune by varying their metal concentration and position. [ABSTRACT FROM AUTHOR]

Abstract In this study, we present a novel numerical model for simulating detonation waves on unstructured grids. In contrast to the conventional finite volume method (FVM), two types of moment comprising the volume-integrated average (VIA) and the point value (PV) at the cell vertex are treated as the evolution variables for the reacting Euler equations. The VIA is computed based on a finite volume formulation of the flux form where the conventional Riemann problem is solved by the HLLC Riemann solver. The PV is updated in a point-wise manner by using the differential formulation where the Roe solver is used to compute the differential Riemann problems. In order to increase the accuracy around discontinuities, numerical oscillations and dissipations are reduced using the boundary variation diminishing algorithm. Convergence tests demonstrated that the proposed model could achieve third-order accuracy with unstructured grids for reacting Euler equations. The high resolution property of the proposed method was verified based on simulations of several detonation wave propagation problems in two and three dimensions. In particular, the current model could resolve the cellular structures with fewer degrees of freedom for the unstable oblique detonation wave problem. These fine structures may be smoothed out by the conventional FVM due to the excessive amount of numerical dissipation errors. Importantly, a simulation of stiff detonation waves showed that the proposed method could capture the correct position of the reaction front whereas the conventional FVMs produced spurious phenomena. Thus, the proposed model can obtain highly accurate solutions for detonation problems on unstructured grids, which is highly advantageous for real applications involving complex geometrical configurations. [ABSTRACT FROM AUTHOR]

Abstract A new three-dimensional (3D) micromechanical model is proposed to simulate the arbitrary multidirectional carbon fiber reinforced polymer (CFRP) composite laminates. Carbon fiber is assumed as transversely isotropic and linear elastic, matrix is assumed as isotropic and elastic–plastic. Maximum strain criterion is used to describe the failure of fiber and matrix. The stresses, strains and damage are described in the fiber and matrix levels, but the debonding between the fiber and matrix and the delamination between two plies are not modeled in the present analysis. Numerical analyses of nonlinear mechanical behavior of angle-ply [±θ] 2s under tension are conducted to verify the validity of the present micromechanical model. Numerical results of nonlinear mechanical behavior, negative Poisson's ratio through the thickness direction, and stress distribution on the free edge show good agreement with previous experimental and analytical results. [ABSTRACT FROM AUTHOR]

A direct Arbitrary Lagrangian Eulerian (ALE) formulation using multi-moment finite volume method for viscous compressible flows on unstructured moving grids has been developed and presented in this paper. High-order polynomials are reconstructed over a compact mesh stencil by making use of both volume integrated average value (VIA) and point values (PV) at the vertices of mesh cells which change in time. By formulating the governing equation in ALE integral form and differential form, the computational variables, VIA and PV, are updated, respectively, by a finite volume scheme and a point-wise discretization using multi-moments (VIA and PV). A simple and efficient formulation is derived for moving mesh which satisfies the geometrical conservation law. In the computations involving moving-body, the PVs of velocity at the vertices of cells adjacent to the body surface are coincided with the motion of the body, which eliminates the numerical approximation to find the cell boundary values on the body surface in conventional finite volume method. Numerical tests are presented to verify the present method as a high-order ALE formulation for compressible flows on both stationary and moving grids. [ABSTRACT FROM AUTHOR]

For the purpose of improvement in interfacial property of carbon fiber composites through a facile process, the carboxyl‐functionalized multiwalled carbon nanotubes (MWCNTs‐COOH) were incorporated into the surface of JH‐T800 carbon fiber using sizing and deposition technology. The surface morphology of MWCNTs‐COOH‐modified carbon fibers and fracture surfaces of unidirectional carbon fiber composites were observed via scanning electron microscopy and atomic force microscopy. According to the results of composites fragmentation test, the adoption of MWCNTs‐COOH‐modified carbon fibers resulted in the improved carbon fiber/epoxy matrix interfacial bonding and interlaminer property by 32.1% and 31.9%, respectively. Through the combination of the above two kinds of pretreating process of carbon fibers, a stress transition layer with the gradient distribution of MWCNTs was built between carbon fiber and resin matrix, which was favorable for releasing stress concentration and hindering the propagation of crack, resulting in a higher reinforcing efficiency for the existing carbon fiber composites. [ABSTRACT FROM AUTHOR]

We present in this work a new reconstruction scheme, so-called MUSCL-THINC-BVD scheme, to solve the five-equation model for interfacial two phase flows. This scheme employs the traditional shock capturing MUSCL (Monotone Upstream-centered Schemes for Conservation Law) scheme as well as the interface sharpening THINC (Tangent of Hyperbola for INterface Capturing) scheme as two building-blocks of spatial reconstruction on the BVD (boundary variation diminishing) principle that minimizes the variations (jumps) of the reconstructed variables at cell boundaries, and thus effectively reduces the dissipation error in numerical solutions. The MUSCL-THINC-BVD scheme is implemented to the volume fraction and other state variables under the same finite volume framework, which realizes the consistency among volume fraction and other physical variables. Numerical results of benchmark tests show that the present method is able to capture the material interface as a well-defined sharp jump in volume fraction, and obtain numerical solutions of superior quality in comparison to other existing methods. The proposed scheme is a simple and effective method of practical significance for simulating compressible interfacial multiphase flows. [ABSTRACT FROM AUTHOR]

• An adaptive signal decomposition is utilized to determine appropriate IMFs. • A 2D image encoding method is proposed with multiresolution for time-serial signals. • Unsupervised training is utilized on noisy labels without any extra datasets. • Experiments verify outstanding performance with different ratios of noisy tags. Power quality disturbances (PQDs) recognition is a vital topic for smart grid governance. Previous work has achieved remarkable success by promoting signal processing and classifier models. However, for some power grids, it is difficult to obtain well-labeled samples for training. Label noise is ubiquitous, which would fail to assess PQDs due to data distribution discrepancy. This article proposes a hybrid approach called PQEventCog for PQD assessing. Firstly, an improved variational mode decomposition is utilized for signal reconstruction. Then, S-transform combined with singular value decomposition is imported to transfer a time-series signal into a 2D time-frequency image for features enhancement. As a potential tool, Differential Training is applied to reduce label noises of training sets. Finally well-labeled samples are fed into a CNN model. A set of analytical signals, as well as real data in a microgrid platform, are performed to confirm the effectiveness and the excellent label-noisy tolerance of PQEventCog. [ABSTRACT FROM AUTHOR]

Discretization of the convection term in a three-cell compact stencil has been widely used in Computational Fluid Dynamics (CFD) of engineering because the second-order interpolation scheme is considered to be more robust and algorithmically simple than very high-order schemes. However, according to Godnunov's theorem, it has never been trivial to design an accurate and oscillation-free discretization scheme in a compact stencil. Over decades, various kinds of schemes have been proposed to increase accuracy beyond second-order without producing non-physical numerical oscillations. Representative schemes are polynomial-based non-linear interpolations such as TVD (Total Variation Diminishing), NVD (Normalized Variable Diagram) and third-order WENO (Weighted Essentially Non-oscillatory); and non-polynomial-based interpolations including RBF (Radial Basis Functions), LDLR (Local Double Logarithmic Reconstruction) and Tangent of Hyperbola for INterface Capturing (THINC). Within the semi-discretization finite volume method, existing reconstruction schemes suffer from different issues to some extent. For example, existing TVD schemes tend to cause smearing, clipping and squaring effects. Most WENO schemes and inconsistent RBF schemes are not scale-invariant. Especially, the improved WENO-Z scheme is neither scale-invariant nor mesh-size-independent. Computationally expensive non-polynomial-based interpolations usually have singularity and are dependent on tunable parameters. Thus, this work reviews reconstruction schemes by reformulating or calculating the reconstructed boundary value in the normalised-variable space where the characteristics of reconstruction schemes can be read directly. Through the accuracy analysis and the induction of existing schemes, this work proposes a Unified Normalised-variable Diagram (UND) where the following properties of a reconstruction scheme can be given diagrammatically: 1) the second-order and the third-order accuracy condition, 2) the TVD and CBC (Convection Boundedness Criterion) constrain, 3) the ENO condition, 4) the High Resolution (HR) property, 5) and the numerical dissipation and anti-dissipation error. The proposed UND framework is firstly demonstrated by the improvement of the existing schemes with a shape-preserving TVD limiter and a scale-invariant WENO scheme. Then, by defining the normalised reconstruction operator, a brand-new scheme named ROUND (Reconstruction Operator on Unified Normalised-variable Diagram) is proposed. The ROUND scheme is devised by directly configuring the normalised reconstruction operator of favourable properties on UND. This work presents a dissipative ROUND scheme in which normalised reconstruction operators are fully in the dissipative region of UND, and a low-dissipative ROUND scheme where rigorously adjusted anti-dissipation errors are introduced. Different formulations of ROUND schemes are presented to show the flexibility of designing schemes within the UND framework. The proposed dissipative and low-dissipative ROUND schemes are evaluated via benchmark tests which show the superior performance of ROUND on accuracy and resolution. Especially, in some cases, the low-dissipative ROUND schemes obtain comparable and even better resolution than classic fifth-order WENO. The significance of this work is further demonstrated by the preliminary results of applying ROUND on the FDM-IBM (Finite Difference Method and Immersed Boundary Method) framework. • A UND framework that unifies existing second-order schemes is proposed. • Improvement of TVD and WENO schemes with UND is presented. • Brand-new ROUND schemes are developed. • The superior performance of ROUND is demonstrated via benchmark tests. [ABSTRACT FROM AUTHOR]

Half grouted sleeve connection is widely used in joining rebars in precast concrete structures. However, its mechanical behaviors at elevated temperatures remain to be a topic with little research. This paper presents experimental results of 12 half grouted specimens and 12 single rebars under static tension at different temperatures. The tensile properties of half grouted sleeve connection were found to be directly affected by the temperature, and some characteristics are different from that of the rebar. The results showed that the half grout sleeves exhibited two types of failure, namely rebar fracture and rebar pullout due to bonding failure. The mechanical properties of specimens were similar to that of single rebars. When the temperature elevated, the failure mode and rebar breakpoint location may change. The bonding length that would be sufficient at room or low temperature, becomes insufficient at 600 °C. Suggestions about the bond length are given to avoid rebar pull out from the grout due to bond failure at elevated temperature. [ABSTRACT FROM AUTHOR]

Background/Aims: Since the first case of novel H7N9 infection was reported, China has experienced five epidemics of H7N9. During the fifth wave, a highly pathogenic H7N9 strain emerged. In order to assess whether the H7N9 vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) was effective in protecting against highly pathogenic H7N9, we conducted this study. Methods: Groups of mice were immunized twice by intraperitoneal injection with 500 µl of either split vaccine alone or MF59-adjuvanted vaccine. Serum was collected 2 weeks after the second vaccine booster. The hemagglutinin inhibition test was conducted on vaccine seed and highly pathogenic H7N9 to evaluate the neutralization of highly pathogenic H7N9. We also immunized mice and challenged them with highly pathogenic H7N9. Mice were observed for illness, weight loss, and death at 1 week and 2 weeks post-infection. Then, the mice were sacrificed and lungs were removed. Antibody responses were assessed and pathological changes in the lung tissue were evaluated.Results: The ability of serum to neutralize highly pathogenic H7N9 was reduced. In mice, highly pathogenic H7N9 was more virulent than A/Zhejiang/DTID-ZJU01/2013(H7N9). After challenge with highly pathogenic H7N9, all mice died while mice challenged with A/Zhejiang/DTID-ZJU01/2013(H7N9) all recovered. The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine was able to protect against infection with highly pathogenic H7N9 in mice, with or without MF59. Moreover, H7N9 vaccine adjuvanted with MF59 produced high antibody levels, which lead to better protection. Conclusions: The A/ZJU01/PR8/2013 split H7N9 avian influenza vaccine based on A/Zhejiang/DTID-ZJU01/2013(H7N9) is effective in protecting against highly pathogenic H7N9. H7N9 vaccine adjuvanted with MF59 offers better protection against infection with highly pathogenic H7N9. In order to make the H7N9 vaccine applicable to humans, further clinical trials are required to evaluate MF59 adjuvanted vaccine. Meanwhile, the vaccine strain should be updated based on the highly pathogenic H7N9 gene sequence. [ABSTRACT FROM AUTHOR]

Previous researches of covalent organic frameworks (COFs) have shown their potential as fluorescent probes, but the regulation of their optical properties and recognition characteristics still remains a challenge, and most of reports required complicated post-decoration to improve the sensing performance. In this context, we propose a novel in-situ strategy to construct uracil-conjugated COFs and modulate their fluorescence properties for sensitive and selective mercury(II) detection. By using 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) and 1,3,6,8-tetrakis(4-aminophenyl)pyrene (TAPPy) as fundamental blocks and 5-aminouraci (5-AU) as the functional monomer, a series of COFs (Py-COFs and Py-U-COFs-1 to Py-U-COFs-5) with tunable fluorescence were solvothermally synthesized through an in-situ Schiff base reaction. The π-conjugated framework serves as a signal reporter, the evenly and densely distributed uracil acts as a mercury(II) receptor, and the regular pores (channels) make the rapid and sensitive detection of the mercury(II) possible. In this research, we manage to regulate the crystalline structure, the fluorescence properties, and the sensing performance of COFs by simply changing the molar ratio of precursors. We expect this research to open up a new strategy for effective and controllable construction of functionalized COFs for environmental analysis. An in-situ strategy is proposed to construct uracil-conjugated COFs and modulate their fluorescence properties for sensitive and selective mercury(II) detection. The π-conjugated framework serves as a signal reporter, the evenly and densely distributed uracil acts as a mercury(II) receptor, and the regular pores (channels) make the rapid and sensitive detection of the mercury(II) possible. [Display omitted] • A novel in-situ strategy was proposed to construct uracil-conjugated COFs. • The crystalline structure and the fluorescence property of COFs can be facilely modulated. • The functionalized COFs demonstrate tunable recognition characteristics toward mercury(II). • Mercury(II) can be sensitively and selectively detected based on the fluorescence quenching. [ABSTRACT FROM AUTHOR]

The design of carbon material-based heterojunction solar cells (HJSCs) provides a promising approach to convert and collect solar energy. With unique photonic, electronic and mechanical properties, versatile carbon materials have attracted considerable attention in the design of heterojunction structures because of the multi-functional applications of carbon materials in the booming field of photovoltaics (PVs). Significant effort has been devoted to enhancing the light absorption capacity and charge/carrier transporting ability to obtain state-of-the-art HJSCs. This review presents the basic application of various carbon materials for PVs and the basic principles of carbon materials in HJSCs. Several optimisation methods for carbon nanotube (CNT) film modification and cell performance, such as optical property and Fermi level tuning, as well as morphological design and interface engineering, are highlighted in a summary of the state-of-art progress of CNT-based HJSCs. Moreover, the representative applications of carbon materials based flexible HJSCs are discussed. Finally, promising pathways and prospects of CNTs in HJSCs and their advanced devices are proposed using film modification, mechanism modulation, and device design to achieve cost-effective, high-performance, and flexible solar cells (SCs). [Display omitted] [ABSTRACT FROM AUTHOR]

This paper presents an innovative approach for predicting timing errors tailored to near-/sub-threshold operations, addressing the energy-efficient requirements of digital circuits in applications, such as IoT devices and wearables. The method involves assessing deep path activity within an adjustable window prior to the root clock's rising edge. By dynamically adapting the prediction window and supply voltage based on error detection outcomes, the approach effectively mitigates false predictions—an essential concern in low-voltage prediction techniques. The efficacy of this strategy is demonstrated through its implementation in a near-/sub-threshold 32-bit microprocessor system. The approach incurs only a modest 6.84% area overhead attributed to well-engineered lightweight design methodologies. Furthermore, with the integration of clock gating, the system functions seamlessly across a voltage range of 0.4 V–1.2 V (5–100 MHz), effectively catering to adaptive energy efficiency. Empirical results highlight the potential of the proposed strategy, achieving a significant 46.95% energy reduction at the Minimum Energy Point (MEP, 15 MHz) compared to signoff margins. Additionally, a 19.75% energy decrease is observed compared to the zero-margin operation, demonstrating successful realization of negative margins. [ABSTRACT FROM AUTHOR]

BACKGROUND The incorporation of β-carotene, one of the most common pigments or bioactives, into food formulations has attracted increasing interest from the food industry, due to its good nutrition and potential health effects. However, it is poorly soluble and unstable in water, which greatly limits its applications in foods. This work presented an effective approach to improve the water dispersibility, stability and even bioaccessibility of β-carotene, using soy protein isolate ( SPI) to perform as effective nanocarriers for this molecule. RESULTS The complexation with SPI remarkably improved the water dispersibility and stability against heating and freeze-drying of β-carotene. However, the encapsulation efficiency and stability of β-carotene in the nanocomplexes with SPI were closely dependent on the applied β-carotene-to-protein ratio, at which the complexation occurred. The best improvement of stability was observed at appropriate β-carotene-to-protein ratios, e.g. 10-20 g kg−1. The complexation with β-carotene mainly occurred on the surface of SPI nanoparticles, through hydrophobic interactions. The complexation resulted in inter-particle aggregation, in a concentration-dependent manner. Almost all of the β-carotene molecules in the nanocomplexes could be progressively released into the aqueous phase. CONCLUSION SPI exhibits a good potential to perform as a nanocarrier for enhanced water dispersibility, stability and bioaccessibility of β-carotene. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

We propose a novel Mach-uniform numerical model for 2D Euler equations on unstructured grids by using multi-moment finite volume method. The model integrates two key components newly developed to solve compressible flows on unstructured grids with improved accuracy and robustness. A new variant of AUSM scheme, so-called AUSM + -pcp ( AUSM + with pressure-correction projection), has been devised including a pressure-correction projection to the AUSM + flux splitting, which maintains the exact numerical conservativeness and works well for all Mach numbers. A novel 3th-order, non-oscillatory and less-dissipative reconstruction has been proposed by introducing a multi-dimensional limiting and a BVD (boundary variation diminishing) treatment to the VPM (volume integrated average (VIA) and point value (PV) based multi-moment) reconstruction. The resulting reconstruction scheme, the limited VPM-BVD formulation, is able to resolve both smooth and non-smooth solutions with high fidelity. Benchmark tests have been used to verify the present model. The numerical results substantiate the present model as an accurate and robust unstructured-grid formulation for flows of all Mach numbers. [ABSTRACT FROM AUTHOR]

The scale-resolving simulation of high speed compressible flow through direct numerical simulation (DNS) or large eddy simulation (LES) requires shock-capturing schemes to be more accurate for resolving broadband turbulence and robust for capturing strong shock waves. In this work, we develop a new paradigm of dissipation-adjustable, shock capturing scheme to resolve multi-scale flow structures in high speed compressible flow. The new scheme employs a polynomial of n-degree and non-polynomial THINC (Tangent of Hyperbola for INterface Capturing) functions of m-level steepness as reconstruction candidates. These reconstruction candidates are denoted as P n T m. From these candidates, the piecewise reconstruction function is selected through the boundary variation diminishing (BVD) algorithm. Unlike other shock-capturing techniques, the BVD algorithm effectively suppresses numerical oscillations without introducing excess numerical dissipation. Then, an adjustable dissipation (AD) algorithm is designed for scale-resolving simulations. This novel paradigm of shock-capturing scheme is named as P n T m − BVD − AD. The proposed P n T m − BVD − AD scheme has following desirable properties. First, it can capture large-scale discontinuous structures such as strong shock waves without obvious non-physical oscillations while resolving sharp contact, material interface and shear layer. Secondly, the numerical dissipation property of P n T m − BVD − AD can be effectively adjusted between n+1 order upwind-biased scheme and non-dissipative n+2 order central scheme through a simple tunable parameter λ. Thirdly, with λ = 0.5 the scheme can recover to n+2 order non-dissipative central interpolation for smooth solution over all wavenumber, which is preferable for solving small-scale structures in DNS as well as resolvable-scale in explicit LES. Finally, the under-resolved small-scale can be solved with the dissipation adjustable algorithm through the so-called implicit LES (ILES) approach. Through simulating benchmark tests involving multi-scale flow structures and comparing with other central-upwind schemes, the superiority of the proposed scheme is evident. For instance, the simulation results of the supersonic planar jet show that P n T m − BVD − AD schemes can achieve competitive results as P n + 2 T m − BVD schemes which utilize a higher degree of reconstruction polynomial. Thus, in comparison with the previous work, the proposed P n T m − BVD − AD schemes have the benefit of a more compact stencil and lower cost. In summary, this work provides an alternative scheme for solving multi-scale problems in high speed compressible flows. • Novel dissipation-adjustable schemes for scale-resolving simulation. • Numerical dissipation is effectively adjusted between high order upwind and central scheme. • Capture discontinuous large-scale structures such as strong shocks without oscillations, and contact with less dissipation. • Small-scale is resolved by non-dissipative central interpolation which can be retrieved over all wavenumber. • Under-resolved scale can be solved with dissipation-adjustable algorithm through ILES approach. [ABSTRACT FROM AUTHOR]