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In numerical welding modelling, it is critically important to adopt a heat source model that fits the actual welding process since the heat source model has significant influence on the calculation accuracy of the transient welding temperature field, especially near the heat source. An inappropriate source model can produce an overestimated or underestimated temperature field, leading to displacement field errors in the mechanical analysis. In this study, a new nonlinear transient peridynamic model employing a variety of heat source models is developed to predict the temperature distribution and displacement variation. More importantly, as an essential physical phenomenon in heat conduction, phase transformation is considered in the peridynamic model. The importance of how the latent heat in the phase change can affect the temperature distribution and displacement field is also emphasized. The simulation results are compared with the finite element method results. Close agreements are observed which demonstrates the capability of the proposed non-linear transient peridynamic model for thermomechanical phase change analysis for welding modelling.

In this article, we reported a novel setup treatment using nitric acid vapor to treat g-C3N4 (CN). By treatment with nitric acid vapour, the basic structure of the CN has not been destroyed. These adoptive treatments enhanced the photocatalytic performance of CN and were reflected in the elimination of rhodamine B (RhB) as well as tetracycline hydrochloride (TC). In comparison to CN, CN-6 demonstrated the highest photocatalytic yield for the breakdown of RhB (99%, in 20 min). Moreover, the excellent reuse of CN-6 for breaking down RhB was also demonstrated. This clearly demonstrated that treatment with nitric acid vapor promoted a blue shift, positively extended its valence band position, and increased the oxidizability of the holes. This also caused CN to disperse better into the aqueous phase, introducing more oxygen-containing functional groups. Thus, treatment with nitric acid vapor has the potential to be applied to delaminate the CN in order to enhance photocatalytic activity.

Bi2WO6 has become a common photocatalyst due to its advantages of simple synthesis and high activity. However, the defects of pure Bi2WO6 such as low light reception hinder its application in photocatalysis. In this study, based on the modification of Bi2WO6 with Ti(IV) as a cavity co-catalyst, new Ni- and Ti-doped nanosheets of Bi2WO6 (Ni/Ti-Bi2WO6) were prepared by a one-step wet thermal impregnation method and used for the photocatalytic degradation of tetracycline. The experimental results showed that the photocatalytic activity of Ni/Ti-Bi2WO6 modified by the two-component catalyst was significantly better than those of pure Bi2WO6 and Ti-Bi2WO6 modified with Ti(IV) only. The photocatalytic effect of Ni/Ti-Bi2WO6 with different Ni/Ti molar ratios was investigated by the degradation of TC. The results showed that 0.4Ni/Ti-Bi2WO6 possessed the best photocatalytic performance, with a degradation rate of 92.9% at 140 min TC. The results of cycling experiments showed that the catalyst exhibited high stability after five cycles. The scavenger experiment demonstrated that the h+ and O2− were the main reactive species. The enhanced photocatalytic activity of Bi2WO6 could be attributed to the synergistic effect between the Ti(IV) as a hole cocatalyst and Ni(II) as an electron cocatalyst, which effectively promoted the separation of photogenerated carriers.

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

Unlike traditional transportation, container transportation is a relatively new logistics transportation mode. Shipping containers lost at sea have raised safety concerns. In this study, finite element analysis of containers subjected to hydrostatic pressure, using commercial software ANSYS APDL was performed. A computer model that can reasonably predict the state of an ISO cargo shipping container was developed. The von Mises stress distribution of the container was determined and the yield strengthwas adopted as the failure criterion. Numerical investigations showed that the conventional ship container cannot withstand hydrostatic pressure in deep water conditions. A strengthened container option was considered for the container to retain its structural integrity in water conditions.

The numerical solution of peridynamics equations is usually done by using uniform spatial discretisation. Although implementation of uniform discretisation is straightforward, it can increase computational time significantly for certain problems. Instead, non-uniform discretisation can be utilised and different discretisation sizes can be used at different parts of the solution domain. Moreover, the peridynamic length scale parameter, horizon, can also vary throughout the solution domain. Such a scenario requires extra attention since conservation laws must be satisfied. To deal with these issues, dual-horizon peridynamics was introduced so that both non-uniform discretisation and variable horizon sizes can be utilised. In this study, dual-horizon peridynamics formulation is derived by using Euler–Lagrange equation for state-based peridynamics. Moreover, application of boundary conditions and determination of surface correction factors are also explained. Finally, the current formulation is verified by considering two benchmark problems including plate under tension and vibration of a plate.

This paper applies the incomplete contracts model to study an optimal banking structure corresponding to different levels of technological development from the perspective of technological innovati...

As a new continuum mechanics formulation, peridynamics has a non-local character by having an internal length scale parameter called horizon. Although the effect of the size of the horizon has been studied earlier, the shape of the horizon can also be influential. In this study, the effect of horizon shape is investigated for both ordinary state-based and non-ordinary state-based peridynamics. Three different horizon shapes are considered including circle, irregular and square. Both static and dynamic analyses are studied by considering plate under tension and vibration of a plate problems. For both static and dynamic conditions, square shape could not capture accurate vertical displacements for ordinary-state based peridynamics. On the other hand, results obtained for all three horizon shapes agree very well with finite element analysis results for non-ordinary state-based peridynamics.

With the development of the vehicle industry and the diversification of lifestyles, as well as the prevalence of the sharing economy, the demand for intelligent cockpits is growing rapidly. If we still design from the perspective of the traditional car cockpit layout, the design of intelligent interaction and connected services will be strongly constrained. This also makes user behavior, new business models and future scenarios become the focus of this research. This paper investigates the above by questionnaire survey method as well as literature method. In this study, user knowledge of smart cockpits is obtained and the scenarios of smart cockpit usage in the sharing economy are predicted. Our findings show that user needs, user experience, EV market and business models have significant effects on the intention of smart cockpits to serve future usage scenarios and their reuse. Our findings also provide guidance and implications for the development of smart cockpits.Keywords: Smart cockpits, Sharing economy, User needs, Future scenarios

Glycinebetaine alleviates chilling stress by protecting photosystems I and II in BADH-transgenic and GB-treated tomato plants, which can be an effective strategy for improving crop chilling tolerance. Tomato (Solanum lycopersicum) is one of the most cultivated vegetables in the world, but is highly susceptible to chilling stress and does not naturally accumulate glycinebetaine (GB), one of the most effective stress protectants. The protective mechanisms of GB on photosystem I (PSI) and photosystem II (PSII) against chilling stress, however, remain poorly understood. Here, we address this problem through exogenous GB application and generation of transgenic tomatoes (Moneymaker) with a gene encoding betaine aldehyde dehydrogenase (BADH), which is the key enzyme in the synthesis of GB, from spinach. Our results demonstrated that GB can protect chloroplast ultramicrostructure, alleviate PSII photoinhibition and maintain PSII stability under chilling stress. More importantly, GB increased the electron transfer between Q

Ontologies, as formal specifications of conceptualisation, are widely used in software engineering to manage software development, maintenance and security concerns. Recently, some ontology services were proposed for software vulnerability detection and showed to be effective. Some could detect more bugs compared to static analysis tools; some could predict hidden bugs based on ontology reasoning. In this paper, we review existing ontology-based services for vulnerability detection techniques, describe their main ideas and design principles, and provide background knowledge for further research in this area.

Efficient multicast support is very important in data center (DC) networks, as many big data systems in data centers are bandwidth-hungry. Multicast implementations in DC networks are usually overlay-based. The major challenges are how can we accurately infer the topology of DC networks with both wired and wireless millimeter wavelength (MMW) links and how to design multicast algorithm for these topologies. In this paper, we first use hierarchical clustering to accurately infer the topology. Then, we propose the Inter-Rack First Multicast (IRFM) algorithm to match the fan-in nature of DC topologies. Evaluation results demonstrate that IRFM is $$3.7{-}11.2{\times }$$ faster than naive multicast implementations in the pure wired case, and $$4.8{-}14.6{\times }$$ faster in the case of MMW enhancement.

A series of new 4-hydroxycoumarin platinum(IV) complexes were designed, synthesized and evaluated as antitumor agents. All the title compounds display moderate to effective antitumor activities toward the tested cell lines and two prominent compounds were screened out with activities comparable to cisplatin and oxaliplatin. The mechanism investigation demonstrates that the platinum(IV) compounds could be reduced to bivalence and exert significant genotoxicity to tumor cells. Meanwhile the coumarin moiety endows the title compounds with cyclooxygenase inhibitory competence which might favour the reduction of tumor-related inflammation and further influence tumor proliferation. The coumarin platinum(IV) complex could effectively induce apoptosis of SKOV-3 cells through up-regulating the expression of caspase3 and caspase9. Furthermore, the conversion of platinum(II) drugs to platinum(IV) form via the conjunction with 4-hydroxycoumarin enhances the drug uptake in whole cells and DNA simultaneously. Moreover, the 4-hydroxycoumarin platinum(IV) complex could combine with human serum albumin via van der Waals force and hydrogen bond, which would influence their transport and bioactivities in vivo.

A series of bi-functional 7-hydroxycoumarin platinum(IV) complexes were synthesized, characterized, and evaluated for antitumor activities. The 7-hydroxycoumarin platinum(IV) complexes display moderate to effective antitumor activities toward the tested cell lines and show much potential in overcoming drug resistance of platinum(II) drugs. In reducing microenvironment, the title compounds could be reduced to platinum(II) complex accompanied with two equivalents of coumarin units. By a unique mechanism, the 7-hydroxycoumarin platinum(IV) complex attacks DNA via the released platinum(II) compound, meanwhile it also inhibits the activities of cyclooxygenase by coumarin fragment. This action mechanism might be of much benefit for reducing tumor-related inflammation in the progress of inhibiting tumor proliferation and overcoming cisplatin resistance. The incorporation of 7-hydroxycoumarin leads to significantly enhanced platinum accumulation in both whole tumor cells and DNA. The HSA interaction investigation reveals that the tested coumarin platinum(IV) compound could effectively combine with HSA via van der Waals force and hydrogen bond.

As an important optical component in laser system, silicon mirror surface is required to have micron-level flatness and subnanometer-level roughness. The research concentrates on how to improve roughness as far as possible while maintaining flatness of silicon mirror surface during chemical mechanical polishing (CMP) process. A polishing edge effect model is established to explain the reason of flatness deterioration, and a roughness theoretical model is set up to get the limit of perfect surface roughness. Based on the models above, a polishing device is designed to maintain the surface flatness, and the optimized polishing process parameters are obtained by orthogonal tests to get a near-perfect surface roughness. Finally the maintenance of flatness and the improvement of roughness can be achieved at the same time in one step of CMP process. This work can be a guide for silicon mirror manufacture to improve optical reflection performance significantly.

Mitochondria-targeting nanotherapy receives great attention these days for its capacity in disrupting mitochondria function and inducing tumor cell apoptosis through external magnetic and optical stimulations. However, the effect is significantly diminished when applied to animal models. The key factors include environmental complexity in vivo and intrinsic protective features of tumor tissues. To address these obstacles and reduce expenses on drug screening, we herein introduce a methodology for producing millimeter-sized spheroids with structural and functional characteristics of tumor tissues in vivo. The necessity of spheroid as a liver tumor model is demonstrated by comparing the effect of TPP-SPIONs (triphenylphosphonium cation-superparamagnetic iron oxide nanoparticles) on monolayer-cultured HepG2 cells and spheroids. Our study reveals that large-scale spheroid, in contrast to monolayer cells, reflects more in vivo tumor characters and is less responsive to TPP-SPIONs during magnetic hyperthermia treatment.

Dark-field microscopy directly detects scattered light from a sample, and therefore requires no fluorescent labeling for single molecule detection. The technique has been extensively used for spectral characterization of nanoscopic particles, but its sensitivity to variations in molecular density has not been explored. 3D chromosome topology plays important roles in regulating life processes. Physical characteristics of DNA (e.g. persistence length) and its interaction with numerous proteins and polyamines determine chromosome and chromatin 3D topology. We herein demonstrate the capacity of dark-field microscopy in real-time monitoring of single DNA molecules' conformation and dynamics. Without fluorescent staining, DNA molecules remain intact in physical characteristics like persistence length, net charges and width of the chain. Exclusion of photobleaching and photocleavage effects allows long-term imaging of bare DNA chains at high ionic strength, in shear flows and in the presence of condensing and stretching agents. Furthermore, our studies reveal that the brightness of single molecules during dark-field imaging is determined by DNA conformation, dark when being stretched and bright upon condensation. The sensitivity of dark-field microscopy to nonuniform distribution of molecular density allows us to study the dynamic activities of the transcriptional factor within the cell membrane. In contrast to a fluorescently tagged antibody, which binds to a specific signaling pathway, variations in molecular density across the nuclear envelope can better represent cellular responses upon stimulation.