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Summary: The energy coupling behavior is propagated through the magnetic field and would seriously affect the operation performance of two‐degree‐of‐freedom motion system based on linear‐rotary motor. This paper proposes a novel double‐stator linear‐rotary switched reluctance motor (DSLR‐SRM) to suppress the energy coupling behavior. First, the structure and operation principles of DSLR‐SRM are presented. The two stators of DSLR‐SRM are radially arranged to perform the independent magnetic circuit and suppress the energy coupling behavior through the magnetic field. Then, an equivalent circuit model is established to shorten the modeling and calculation time. It could be found that the energy coupling behavior directly affects the torque and force performance. Next, the sensitivity of the DSLR‐SRM dimensions is developed. Meanwhile, the dimensions of DSLR‐SRM are optimized to enhance the torque and force output via TOPSIS decision‐making. Finally, the validity of equivalent circuit modeling analysis and optimization results are verified through three‐dimensional finite element model. [ABSTRACT FROM AUTHOR]

This paper reports the application of multi-component hydrocracking catalyst grading technology in diesel hydrocracking system to increase naphtha, and studies the influence of catalyst systems with different number of graded beds on the reaction process of diesel hydrocracking. Three hydrocracking catalysts with different physicochemical properties as gradation components, the diesel hydrocracking reaction on catalyst systems of one-component, two-component and three-component graded beds with different loading sequences are carried out and evaluated, respectively. The catalytic mechanism of the multi-component grading system is analyzed. The results show that, with the increase of the number of grading beds, the space velocity of reaction on each catalyst increases, which can effectively control the overreaction process; along the flow direction of feedstock, the loading sequences of catalysts with acidity decreasing and pore properties increasing can satisfy the demand of different catalytic activity for the conversion of reactant with changing composition to naphtha, which has a guiding role in the conversion of feedstock to target products. Therefore, the conversion of diesel, the selectivity and yield of naphtha all increase significantly on the multi-component catalyst system. The research on the grading technology of multi-component catalysts is of great significance to the promotion and application of catalyst systems in various catalytic fields. [ABSTRACT FROM AUTHOR]

Thin-walled tubular structures are widely employed in applications. The current study proposes an innovative cost-saving and eco-friendly thin-walled cylinder concept using recycled beverage cans. Axial compression experiments are conducted to characterize the crushing performance under quasi-static and dynamic loading. Besides, the polyurethane foam (PUF)-filled beverage cans are fabricated to improve the compression resistance and energy absorption capacity. Experimental results show that empty beverage cans behave as a typical Type-II absorber and fail by local buckling of the cylinder belly. The initial peak force increases with deformation rates while the highest mean crushing force is obtained at compressive velocity of 50 mm/min. In contrast, PUF-filled beverage cans collapse with a progressive folding process and present significant improvement in crashworthiness. Experimental results are compared with theoretical analysis and conventional energy absorbers to clarify the crashworthiness. In addition, the interaction effect between the PUF fillings and the recycled beverage cans is discussed comprehensively. [ABSTRACT FROM AUTHOR]

Chrysanthemum morifolium ‗Chuju' is a famous medicinal species in traditional Chinese medicine. ‗Chuju' contains various active ingredients that can be used to treat multiple diseases without toxic side effects. In the present study, we combined metabolomics and network pharmacology to further explore the active ingredients in ‗Chuju', as well as the target and pharmacological mechanisms of the active ingredients. A visualized network analysis model based on chemistry, pharmacokinetics, and pharmacology was constructed to predict the potential pharmacological mechanism of ‗Chuju'. A total of 424 metabolites of ‗Chuju' were identified, of which 21 ingredients had positive pharmacological effects after ADME screening. The network pharmacology revealed that acacetin and beta-sitosterol in ‗Chuju' could act on GSK3B, MAPK14, ADRA1R, and NOS2 to regulate diabetes mellitus, Alzheimer's disease, breast cancer, and inflammatory diseases. These results indicated the potential pharmacological effects of the active components in ‗Chuju'. [ABSTRACT FROM AUTHOR]

• Exact analytical solutions of stress distributions in a hollow cylinder under contact interactions are established. • Governing equations are analytically uncoupled by introducing displacement functions. • Hertz contact is re-written as Fourier series to create a versatile description of contact interactions. • Effects of design parameters on stress fields are comprehensively discussed. • Novel maximum normalized stress maps are created for stress distribution mechanism analysis. Bundled hollow cylinders are extensively found in natural materials and engineering structures. Aiming at a theoretical basis of structural rigidity and integrity, the present study provides exact analytical solutions of stress distribution within a hollow cylinder under contact tractions by the neighbors in one-dimensional chains. Displacement functions are introduced to uncouple the governing equations, and explicit expressions of stress components are obtained. Hertz contact at the interaction surface is considered and re-written by Fourier series to determine the unknown coefficients. Traits of stress distribution within the hollow cylinder are addressed and significant non-uniformity is indicated along both the radius and circumference. Parameter studies are conducted to investigate the effects of material and geometry on the stress distribution. Furthermore, novel maximum normalized stress maps are developed, providing an effective approach to understand stress distribution mechanisms. The ultimate stress transits from the circumferential compressive type to the radial compressive type with the increasing thickness-diameter ratio. If excluding compressive stresses, the hoop tensile and the in-plane shear types are predominant for different thickness-diameter ratios, respectively. The present investigation should help to understand the failure mechanisms and can be utilized to create a versatile method of engineering materials constructed by bundled hollow cylinders. [Display omitted] [ABSTRACT FROM AUTHOR]

• An eco-friendly and low-cost sustainable sandwich structure with cork stopper cores is proposed. • Natural frequencies of the sustainable sandwich panel are theoretically predicted. • Effect of the cork stopper geometric parameters on modal performance is comprehensively addressed. • Influence of packing configuration of cork stoppers on dynamic behaviors is determined. Cork is a natural sustainable material, which is widely used for wine bottle stopper. This paper proposes an environment-friendly and low-cost sandwich concept consisting of cork stoppers and aluminum covering skins for a novel building material solution. A set of prototypes with natural and agglomerated cork stopper cores are fabricated respectively. Modal tests are carried out to address the effect of arrangement orientations in the cores on natural frequencies. Besides, theoretical and finite element analysis are conducted to determine vibration behaviors of the sustainable sandwich structures. The results show that the natural frequencies of the sustainable sandwich panels are highly affected by the parent materials and packing configurations. Furthermore, the effects of cork stopper core dimensions on the vibration performance are determined by a parametric study, providing comprehensive information for sustainable building structure development and waste management. [ABSTRACT FROM AUTHOR]

4D printing enables 3D printed structures to change shape over "time" in response to environmental stimulus. Because of relatively high modulus, shape memory polymers (SMPs) have been widely used for 4D printing. However, most SMPs for 4D printing are thermosets, which only have one permanent shape. Despite the efforts that implement covalent adaptable networks (CANs) into SMPs to achieve shape reconfigurability, weak thermomechanical properties of the current CAN-SMPs exclude them from practical applications. Here, we report reconfigurable 4D printing via mechanically robust CAN-SMPs (MRC-SMPs), which have high deformability at both programming and reconfiguration temperatures (>1400%), high Tg (75°C), and high room temperature modulus (1.06 GPa). The high printability for DLP high-resolution 3D printing allows MRC-SMPs to create highly complex SMP 3D structures that can be reconfigured multiple times under large deformation. The demonstrations show that the reconfigurable 4D printing allows one printed SMP structure to fulfill multiple tasks.. [ABSTRACT FROM AUTHOR]

Needle-punched carbon/carbon (NP C/C) composite is widely used in rocket-engine nozzles and re-entry vehicles. Recyclable technology expedited the research on repeated oxidation and residual mechaincal properties of thermal-protection materials. In this study, the critical longitudinal compression strengths before and after oxidation are derived based on the Timoshenko beam theory. Three repetitions of short-term oxidation cycles and compression experiments are investigated. The average oxidation rate of this composite was 5∼6% in 10 min and kept linear increase. In-plane and out-of-plane compressive strengths of NP C/C composite diminish quasi-linearly due to oxidation at 1000°C, with their moduli decreasing in a periodically slow-sharp pattern. After three oxidation cycles, the levels of residual in-plane modulus and strength were 55.20% and 56.89%, respectively, while the resudual out-of-plane modulus and strength were 44.65% and 47.23%, respectively. The results showed that the material exhibited the pesudo-plastical behaviour after oxidation, cracks grew along the punched conical structures formed by the punching technology. In-plane and out-of-plane modulus were more sensitive than their strengths after first oxidation cycle. [ABSTRACT FROM AUTHOR]

In order to select and cultivate germplasm resources of Leymus chinensis suitable for planting in Hinggan League area, four wild Leymus chinensis germplasm resources from different geographical distribution in Hinggan League were tested for phenological characteristics, morphological indexes, quantitative indexes and nutritional indexes, and correlation analysis and comprehensive evaluation were carried out. The results showed that both morphological and quantitative traits had different degrees of variation, ranging from 2.11%~43.10%. Among the nutritional indexes, the coefficient of variation of dry matter is the smallest, which is 0.26%. The coefficient of variation of crude protein is the highest, which is 20.94%. There was a significant positive correlation between plant height and leaf width (P<0.05) and extremely significant positive correlation with dry weight (P<0.01). The ranking of weighted correlation degree was YC01> YC02>YC04>YC03. The study indicates that YC01 germplasm has good production performance and comprehensive performance in Hinggan League. [ABSTRACT FROM AUTHOR]

Some cancers such as human breast cancer, prostate cancer, and lung cancer easily metastasize to bone, leading to osteolysis and bone destruction accompanied by a complicated microenvironment. Systemic administration of bisphosphonates (BP) or denosumab is the routine therapy for osteolysis but with non-negligible side effects such as mandibular osteonecrosis and hypocalcemia. Thus, it is imperative to exploit optimized drug delivery systems, and some novel nanotechnology and nanomaterials have opened new horizons for scientists. Targeted and local drug delivery systems can optimize biodistribution depending on nanoparticles (NPs) or microspheres (MS) and implantable biomaterials with the controllable property. Drug delivery kinetics can be optimized by smart and sustained/local drug delivery systems for responsive delivery and sustained delivery. These delicately fabricated drug delivery systems with special matrix, structure, morphology, and modification can minimize unexpected toxicity caused by systemic delivery and achieve desired effects through integrating multiple drugs or multiple functions. This review summarized recent studies about optimized drug delivery systems for the treatment of cancer metastatic osteolysis, aimed at giving some inspiration in designing efficient multifunctional drug delivery systems. [ABSTRACT FROM AUTHOR]

Figuring out rock strength plays essential roles in the sub ground mining activities, such as oil and gas well drilling and hydraulic fracturing, coal mining, tunneling, and other civil engineering scenarios. To help understand the effects of the mineralogical composition on evaluating the rock strength, this research tries to establish indirect prediction models of rock strength by specific input mineral contents for common sedimentary rocks. Using rock samples collected from the outcrops in the Sichuan Basin, uniaxial compression tests have been conducted to sandstone, carbonate, and shale cores. Combining with statistical analysis, the experimental data prove it true that the mineralogical composition can be utilized to predict the rock strength under specific conditions but the effects of mineralogical composition on the rock strength highly depend on the rock lithologies. According to the statistical analysis results, the predicted values of rock strengths by the mineral contents can get high accuracies in sandstone and carbonate rocks while no evidences can be found in shale rocks. The best indicator for predicting rock strength should be the quartz content for the sandstone rocks and the dolomite content for the carbonate rocks. Especially, to improve the evaluation accuracy, the rock strengths of sandstones can be obtained by substituting the mineral contents of quartz and clays, and those of carbonates can be calculated by the mineral contents of dolomite and calcite. Noticeably, the research data point out a significant contrast of quartz content in evaluating the rock strength of the sandstone rocks and the carbonate rocks. Increasing quartz content helps increase the sandstone strength but decrease the carbonate strength. As for shale rocks, no relationship exists between the rock strength and the mineralogical composition (e.g., the clay fractions). To provide more evidences, detailed discussion also provides the readers more glances into the framework of the rock matrix, which can be further studied in the future. These findings can help understand the effects of mineralogical composition on the rock strengths, explain the contrasts in the rock strength of the responses to the same mineral content (e.g., the quartz content), and provide another indirect method for evaluating the rock strength of common sedimentary rocks. [ABSTRACT FROM AUTHOR]

Since first developed, the conducting materials in wireless communication and electromagnetic interference (EMI) shielding devices have been primarily made of metal-based structures. Here, we present a graphene-assembled film (GAF) that can be used to replace copper in such practical electronics. The GAF-based antennas present strong anticorrosive behavior. The GAF ultra-wideband antenna covers the frequency range of 3.7 GHz to 67 GHz with the bandwidth (BW) of 63.3 GHz, which exceed ~110% than the copper foil-based antenna. The GAF Fifth Generation (5G) antenna array features a wider BW and lower sidelobe level compared with that of copper antennas. EMI shielding effectiveness (SE) of GAF also outperforms copper, reaching up to 127 dB in the frequency range of 2.6 GHz to 0.32 THz, with a SE per unit thickness of 6,966 dB/mm. We also confirm that GAF metamaterials exhibit promising frequency selection characteristics and angular stability as flexible frequency selective surfaces. [ABSTRACT FROM AUTHOR]

In this study, an epoxy resin, YZ-05, designed specifically for carbon fiber reinforced polymer prepregs, was characterized and modeled. A degassing method for the highly viscous YZ-05 was established for specimen preparation. To numerically model the behavior of YZ-05 in curing, several components, including the heat transfer, curing kinetics, and viscoelastic constitutive law ones, were developed, and the corresponding material properties to be input were tested. As YZ-05 shows severe creep at high temperature under mechanical loading, the combination of digital image correlation (DIC) and thermography technique was utilized to obtain its thermal expansion and chemical shrinkage. In the aspects of viscoelastic behavior, stress relaxation tests were performed based on time-temperature superposition principle with a numerical method to calculate shift factors. After development and input identification, these modeling components for YZ-05 resin were integrated and the modeling results were validated using experiments, where bending of resin beams was induced during curing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Simple blade coating technique to achieve large-scale self-assembly of graphene oxide (GO) flakes into anisotropic films with gradient structures and controlled patterning. • Statistical analysis method utilizing scanning electron microscopy images for the characterization of materials with macroscopic surface morphology. • Sensing/actuation behavior, responding to external stimuli such as temperature, humidity, and light. • Robust and flexible materials are suitable for application as integral building elements in the bioinspired design of sustainable smart housing and green constructs. Sustainable structural design, utilizing material to imitate natural biological systems, presents both promise and challenges. By avoiding interfacial problems encountered in composite counterparts, such designs offer self-adaptive materials for smart housing and green architecture, etc. In this study, we demonstrate the feasibility of large-scale self-assembly of graphene oxide (GO) flakes into anisotropic films through a simple blade coating technique. Through the application of blade coating to a highly concentrated nematic GO suspension, we successfully fabricate GO films with morphological gradient and patterning. Additionally, we propose a statistical analysis method utilizing scanning electron microscopy (SEM) images for the characterization of materials with macroscopic surface morphology. Furthermore, we explore the application of these GO films as low-dimensional soft actuators, revealing their outstanding stimuli-responsive performance and self-adaptation to environment. Such robust and flexible films can be used as integral building elements in the bioinspired design of sustainable smart housing facilitating remote robotization and sensing capabilities. [ABSTRACT FROM AUTHOR]

• Novel bolt-connected precast concrete walls (PCWs) enhanced by UHPC were proposed. • The PCW enhanced by UHPC exhibited similar seismic behavior to the monolithic wall. • Theoretical calculations for the flexural strength of PCWs were formulated. Existing bolted precast concrete walls (PCWs) have shown disadvantages in terms of high precision in production or insufficient seismic performance compared with cast-in situ walls. Based on this background, new bolt-connected PCWs enhanced by ultra-high performance concrete (UHPC) and connected by spliced bolted joints for use in low-to mid-rise residential systems were proposed. Seven specimens, including one monolithic concrete wall and six bolt-connected PCWs, were tested at a low axial compression ratio and reversed cyclic loads. The effects of the UHPC enhancement area, bolt arrangement, joint position and bolt hole shape of the steel plate on the seismic performance of the PCW were evaluated. The test results indicate that three types of failure patterns could be observed in PCWs, i.e., wall toe compressive failure, joint shear failure and flexural failure. The PCW enhanced by UHPC was able to achieve equivalent performance to the monolithic wall in terms of lateral resistance and energy dissipation. In addition, theoretical calculations for the flexural strength of PCWs corresponding to different failure modes were proposed. The predicted results approximated the test values and were all within the safe range. [ABSTRACT FROM AUTHOR]