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Pressure sensors have widespread applications across various fields in air and underwater environments. However, the drastic pressure difference makes it hard for pressure sensors to measure air and deep-sea pressure under the same mechanism. In this study, we present a design of a capacitive pressure sensor based on the soft sensing membrane bending deformation to measure air pressure or extreme hydrostatic pressure. A mechanical model was developed to analyze the relationship between the membrane capacitance and the external pressure condition on different compressible mediums of the sensor. By changing the compressible mediums, the deformability of the sensor membrane under load can be modulated, enabling rapid adjustments to the working range of the sensor by at least four to five orders of magnitude. In the experiments, the sensor demonstrated the capability to monitor gas pressures of 1 kPa in air and hydrostatic pressures of 100 MPa (equal to hydrostatic pressure at a depth of 10000 m) in the pressure vessel. With consistent and stable performance across a low-to-high measurement range, this sensor proves versatile for applications such as wind pressure, depth, and environmental pressure measurements.

Constant-current anodization of pure aluminum was carried out in non-corrosive capacitor working electrolytes to study the formation mechanism of nanopores in the anodic oxide films. Through comparative experiments, nanopores are found in the anodic films formed in the electrolytes after high-temperature storage (HTS) at 130 °C for 240 h. A comparison of the voltage−time curves suggests that the formation of nanopores results from the decrease in formation efficiency of anodic oxide films rather than the corrosion of the electrolytes. FT-IR and UV spectra analysis shows that carboxylate and ethylene glycol in electrolytes can easily react by esterification at high temperatures. Combining the electronic current theory and oxygen bubble mold effect, the change in electrolyte composition could increase the electronic current in the anodizing process. The electronic current decreases the formation efficiency of anodic oxide films, and oxygen bubbles accompanying electronic current lead to the formation of nanopores in the dense films. The continuous electronic current and oxygen bubbles are the prerequisites for the formation of porous anodic oxides rather than the traditional field-assisted dissolution model.

Immunosuppression by the tumor microenvironment is a pivotal factor contributing to tumor progression and immunotherapy resistance. Priming the tumor immune microenvironment (TIME) has emerged as a promising strategy for improving the efficacy of cancer immunotherapy. In this study we investigated the effects of noninvasive radiofrequency radiation (RFR) exposure on tumor progression and TIME phenotype, as well as the antitumor potential of PD-1 blockage in a model of pulmonary metastatic melanoma (PMM). Mouse model of PMM was established by tail vein injection of B16F10 cells. From day 3 after injection, the mice were exposed to RFR at an average specific absorption rate of 9.7 W/kg for 1 h per day for 14 days. After RFR exposure, lung tissues were harvested and RNAs were extracted for transcriptome sequencing;PMM-infiltrating immune cells were isolated for single-cell RNA-seq analysis. We showed that RFR exposure significantly impeded PMM progression accompanied by remodeled TIME of PMM via altering the proportion and transcription profile of tumor-infiltrating immune cells. RFR exposure increased the activation and cytotoxicity signatures of tumor-infiltrating CD8+T cells, particularly in the early activation subset with upregulated genes associated with T cell cytotoxicity. The PD-1 checkpoint pathway was upregulated by RFR exposure in CD8+T cells. RFR exposure also augmented NK cell subsets with increased cytotoxic characteristics in PMM. RFR exposure enhanced the effector function of tumor-infiltrating CD8+T cells and NK cells, evidenced by increased expression of cytotoxic molecules. RFR-induced inhibition of PMM growth was mediated by RFR-activated CD8+T cells and NK cells. We conclude that noninvasive RFR exposure induces antitumor remodeling of the TIME, leading to inhibition of tumor progression, which provides a promising novel strategy for TIME priming and potential combination with cancer immunotherapy.

Living tissues, such as skeletal muscles, are capable of remodeling and self-growth in response to their mechanical environment. In contrast, synthetic materials, once formed, have little ability to grow and reconstruct. Recently, mechanoresponsive self-growing hydrogel, a novel hydrogel that can grow under mechanical stresses, has been reported. However, the chemomechanics underpinning the growth and strengthening behaviors of mechanoresponsive self-growing hydrogels remains largely unexplored. Here, we present a chemomechanical model for mechanoresponsive self-growing hydrogels by developing and integrating theories of mechanoradical generation due to chain rupture, chemical kinetics of polymerization, and new network formation. The chemomechanical model is applied to theoretically investigate the concentration of mechanoradical generated by stretching hydrogels, the polymerization kinetics of monomers and cross-linkers, and the strengthened mechanical behavior of self-growing hydrogels due to new network formation. Finally, we employ the theory to predict the stress–stretch responses of self-growing hydrogels under repetitive loading–unloading and growth cycles in the closed system. The results, especially the predicted ultimate stresses of the hydrogel over cycles, agree well with experimental measurements made by Matsuda et al. and can consistently explain the experimentally observed mechanical behaviors of self-growing hydrogels.

Improved markers for predicting recurrence are needed to stratify patients with localised (stage I–III) renal cell carcinoma after surgery for selection of adjuvant therapy. We developed a novel assay integrating three modalities—clinical, genomic, and histopathological—to improve the predictive accuracy for localised renal cell carcinoma recurrence.

Amethystoidesic acid (1), a triterpenoid with an unprecedented 5/6/6/6 tetracyclic skeleton, and six undescribed diterpenoids, amethystoidins A–F (2–7), were isolated from the rhizomes of Isodon amethystoidesalong with 31 known di- and triterpenoids (8–38). Their structures were fully elucidated via extensive spectroscopic analysis including 1D and 2D NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) calculations. Compound 1is the first example of a triterpenoid possessing a rare ring system (5/6/6/6) derived from a contracted A-ring and the 18,19-seco-E-ring of ursolic acid. Compounds 6, 16, 21, 22, 24, and 27significantly inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, which could be partly mediated by the downregulation of LPS-induced inducible nitric oxide synthase (iNOS) protein expression.

LZTFL1 is a tumor suppressor located in chromosomal region 3p21.3 that is deleted frequently and early in various cancer types including the kidney cancer. However, its role in kidney tumorigenesis remains unknown. Here we hypothesized a tumor suppressive function of LZTFL1 in clear cell renal cell carcinoma (ccRCC) and its mechanism of action based on extensive bioinformatics analysis of patients’ tumor data and validated it using both gain- and loss-functional studies in kidney tumor cell lines and patient-derive xenograft (PDX) model systems. Our studies indicated that LZTFL1 inhibits kidney tumor cell proliferation by destabilizing AKT through ZNRF1-mediated ubiquitin proteosome pathway and inducing cell cycle arrest at G1. Clinically, we found that LZTFL1 is frequently deleted in ccRCC. Downregulation of LZTFL1 is associated with a poor ccRCC outcome and may be used as prognostic maker. Furthermore, we show that overexpression of LZTFL1 in PDX via lentiviral delivery suppressed PDX growth, suggesting that re-expression of LZTFL1 may be a therapeutic strategy against ccRCC.

The discontinuous Galerkin time-domain (DGTD) method accelerated by local time-stepping (LTS) and parallel techniques is employed to analyze the time-domain shielding effectiveness (TDSE) of metallic enclosures. The detailed formulations and implementation procedures of the DGTD method and LTS and parallel techniques are introduced. Numerical results validate the correctness of the proposed method. Moreover, the influence of various design parameters of the metallic enclosure, including aperture dimensions, wall thickness, spacing of aperture arrays, etc., on the TDSE are analyzed by the proposed method. Some rules are given for the design of the enclosure with rectangular apertures from the perspective of TDSE. The proposed method provides an extremely powerful tool for the evaluation of TDSE.

Mixed integer linear programming (MILP) is an NP-hard problem, which can be solved by the branch and bound algorithm by dividing the original problem into several subproblems and forming a search tree. For each subproblem, linear programming (LP) relaxation can be solved to find the bound for making the following decisions. Recently, with the increasing dimension of MILPs in different applications, how to accelerate the solution process becomes a huge challenge. In this survey, we summarize techniques and trends to speed up MILP solving from two perspectives. First, we present different approaches in simplex initialization, which can help to accelerate the solution of LP relaxation for each subproblem. Second, we introduce the learning-based technologies in branch and bound algorithms to improve decision making in tree search. We also propose several potential directions and extensions to further enhance the efficiency of solving different MILP problems.

Ionic conductive elastomers (ICEs), thanks to their liquid-free nature, have emerged as one of the most promising candidates for conductors in soft ionotronics. Notably, most ionotronic devices need to work in ambient environments where the presence of water molecules is ubiquitous. Thus far, the long-term impact of ambient water on the performances of ICEs remains virtually unexplored. Here, we show that air-aged ICEs absorb a very low amount of environmental water (∼0.3–0.6 wt % of the ICEs), which endows ICEs with stable mechanical performance and strongly boosted conductivity. We study the underlying molecular mechanism and clarify that the scission of lithium bonds between lithium ions and elastomer chains provoked by diffusing water molecules accounts for the observed changes in ICE properties. This work provides guidance for the practical mass application of ICE-based soft ionotronics in ambient environments.

Eyewear displays have been gradually adopted in entertainment, industrial, and medical applications. The optical performance and image quality of the eyewear displays are required to be precisely evaluated and quantified. This challenges the conventional light measuring devices since the displays are viewed in an immersed environment and at a much closer viewing distance from the display to the eye. In eyewear display, measurement within the eye box and the LMD to mimic the eyeball movement is the first step to ensure an accurate measurement. This paper explained the difference of eyeball location in LMD measurement. The comparison between the eye pupil center and eyeball rotation center which are currently included in the IEC 63145 series standards is discussed. We experimented with the setups in the measurement system and set eye rotation at the pupil and at the eyeball center for contrast ratio and Michelson contrast. The experimental results were discussed to understand the differences between eye pupil center rotation and eyeball center rotation.

Surface plasmon resonance (SPR) bridges photonics and photoelectrochemistry by providing an effective interaction between absorption and confinement of light to surface electrons of plasmonic metal nanostructures (PMNs). SPR enhances the Raman intensity enormously in surface-enhanced Raman spectroscopy (SERS) and leads to the plasmon-mediated chemical reaction on the surface of nanostructured metal electrodes. To observe variations in chemical reactivity and selectivity, we studied the SPR photoelectrochemical reactions of para-aminobenzoic acid (PABA) on nanostructured gold electrodes. The head-to-tail coupling product “4-[(4-imino-2,5-cyclohexadien-1-ylidene)amino]benzoic acid (ICBA)” and the head-to-head coupling product p,p′–azodibenzoate (ADBA) were obtained from PABA adsorbed on PMN-modified gold electrodes. In particular, under acidic and neutral conditions, ICBA was obtained as the main product, and ADBA was obtained as the minor product. At the same time, under basic conditions, ADBA was obtained as the major product, and ICBA was obtained as the minor product. We have also provided sufficient evidence for the oxidation of the tail-to-tail coupling reaction product that occurred in a nonaqueous medium rather than in an aqueous medium. The above finding was validated by the cyclic voltammetry, SERS, and theoretical calculation results of possible reaction intermediates, namely, 4-aminophenlylenediamine, 4-hydroxyphenlylenediamine, and benzidine. The theoretical adsorption model and experimental results indicated that PABA has been adsorbed as para-aminobenzoate on the gold cluster in a bidentate configuration. This work offers a new view toward the modulation of selective surface catalytic coupling reactions on PMN, which benefits the hot carrier transfer efficiency at photoelectrochemical interfaces.

The deep sea remains the largest unknown territory on Earth because it is so difficult to explore1–4. Owing to the extremely high pressure in the deep sea, rigid vessels5–7and pressure-compensation systems8–10are typically required to protect mechatronic systems. However, deep-sea creatures that lack bulky or heavy pressure-tolerant systems can thrive at extreme depths11–17. Here, inspired by the structure of a deep-sea snailfish15, we develop an untethered soft robot for deep-sea exploration, with onboard power, control and actuation protected from pressure by integrating electronics in a silicone matrix. This self-powered robot eliminates the requirement for any rigid vessel. To reduce shear stress at the interfaces between electronic components, we decentralize the electronics by increasing the distance between components or separating them from the printed circuit board. Careful design of the dielectric elastomer material used for the robot’s flapping fins allowed the robot to be actuated successfully in a field test in the Mariana Trench down to a depth of 10,900 metres and to swim freely in the South China Sea at a depth of 3,224 metres. We validate the pressure resilience of the electronic components and soft actuators through systematic experiments and theoretical analyses. Our work highlights the potential of designing soft, lightweight devices for use in extreme conditions.

The 2024 aluminum alloy was prepared with different ultrasonic processes. Effects of ultrasonic treatment parameters including ultrasonic power, treatment time, treatment temperature, and frequency resonance, as well as C2Cl6degasser on degassing of the 2024 aluminum alloy were investigated. Results indicate that increasing ultrasonic power at the same ultrasonic treatment time can improve the degassing effect. The optimum degassing efficiency can be obtained under the resonant ultrasound condition. With the combination of 1% C2Cl6addition and 150 W ultrasonic treatment for 40 s, the hydrogen content of the alloy is decreased by 52.9%. At the same time, the tensile strength and elongation are increased by 28.3% and 92.3%, respectively, and the yield strength is slightly increased by 6.7%. The degassing mechanism is also discussed.

An attractive field of plasmon-mediated chemical reactions (PMCRs) is developing rapidly, but there is still incomplete understanding of how to control the kinetics of such a reaction related to hot carriers. Here, we chose 8-bromoadenine (8BrAd) as a probe molecule of hot electrons to investigate the influence of the electrode potential, laser wavelength, and power on the PMCR kinetics on silver nanoparticle-modified silver electrodes. Plasmonic hot electron-mediated cleavage of the C–Br bond in 8BrAd has been investigated by combining in situ electrochemical surface-enhanced Raman spectroscopy and density functional theory calculations. The experimental and theoretical results reveal that the energy position of plasmon relaxation-generated hot electrons can be modulated conveniently by applied potentials and laser light. This allows the proposal of a mechanism of modulating the matching energy of the hot electron of plasmon relaxation to promote the efficiency of PMCRs in electrochemical interfaces. Our work will be helpful to design surface plasmon resonance photoelectrochemical reactions on metal electrode surfaces of nanostructures with higher efficiency.

A new type of AZ31-1.3Ca-1.0Sm-0.3La alloy was obtained in this study by adding Ca, Sm and La to AZ31 alloy. Detailed analysis results on second phases showed that Al2Ca phases, Al2Sm phases with two kinds of morphologies formed in as-cast AZ31-1.3Ca-1.0Sm-0.3La alloy besides Mg17Al12 phases, and La atoms mainly dissolved in Al2Ca/Sm phases. The average grain size of as-cast AZ31-1.3Ca-1.0Sm-0.3La alloys was 212 μm and the grain sizes distributions were uniform. After the hot extrusion, the average grain size decreased to 5.4 μm and the grain sizes distributions were uneven. The base texture of as-extruded AZ31-1.3Ca-1.0Sm-0.3La alloy was strong, and the maximum density value was 3.25. The yield strength, ultimate tensile strength and elongation of as-extruded AZ31-1.3Ca-1.0Sm-0.3La alloy was 216 MPa, 280 MPa and 16% at RT, and 145 MPa, 188 MPa and 42% at 150°C, respectively, which are much higher than those of the common MB2 alloy both at the room temperature and 150 °C.

As one of the most promising drug delivery carriers, hydrogels have received considerable attention in recent years. Many previous efforts have focused on diffusion-controlled release, which allows hydrogels to load and release drugs in vitro and/or in vivo. However, it hardly applies to lipophilic drug delivery due to their poor compatibility with hydrogels. Herein, we propose a novel method for lipophilic drug release based on a dual pH-responsive hydrogel actuator. Specifically, the drug is encapsulated and can be released by a dual pH-controlled capsule switch. Inspired by the deformation mechanism of Drosera leaves, we fabricate the capsule switch with a double-layer structure that is made of two kinds of pH-responsive hydrogels. Two layers are covalently bonded together through silane coupling agents. They can bend collaboratively in a basic or acidic environment to achieve the “turn on” motion of the capsule switch. By incorporating an array of parallel elastomer stripes on one side of the hydrogel bilayer, various motions (e.g., bending, twisting, and rolling) of the hydrogel bilayer actuator were achieved. We conducted an in vitro lipophilic drug release test. The feasibility of this new drug release method is verified. We believe this dual pH-responsive actuator-controlled drug release method may shed light on the possibilities of various drug delivery systems.

Conclusions: Computed tomography angiography is essential for assessing the condition of the remaining embolic coils. In cases with thrombosed parent arteries, a conservative approach, like the transection of exposed coils, can be employed as part of the management strategy.

Maintaining the concentrations of various ions in body fluids is critical to all living organisms. In this contribution, we designed a flexible microneedle patch coupled electrode array (MNP-EA) for the in situ multiplexed detection of ion species (Na+, K+, Ca2+, and H+) in tissue interstitial fluid (ISF). The microneedles (MNs) are mechanically robust for skin or cuticle penetration (0.21 N/needle) and highly swellable to quickly extract sufficient ISF onto the ion-selective electrochemical electrodes (∼6.87 μL/needle in 5 min). The potentiometric sensor can simultaneously detect these ion species with nearly Nernstian response in the ranges wider enough for diagnosis purposes (Na+: 0.75–200 mM, K+: 1–128 mM, Ca2+: 0.25–4.25 mM, pH: 5.5–8.5). The in vivo experiments on mice, humans, and plants demonstrate the feasibility of MNP-EA for timely and convenient diagnosis of ion imbalances with minimal invasiveness. This transdermal sensing platform shall be instrumental to home-based diagnosis and health monitoring of chronic diseases and is also promising for smart agriculture and the study of plant biology.

Development of stresses in silicon (Si) anodes of lithium-ion batteries is strongly affected by its mechanical properties. Recent experiments reveal that the mechanical behavior of lithiated silicon is viscoplastic, thereby indicating that lithiation-induced mechanical stresses are dependent on the lithiation reaction rate. Experimental evidence also accumulates that the rate of lithiation reaction is conversely affected by the magnitude of mechanical stresses. These experimental observations demonstrate that lithiation reaction and stress generation in silicon anodes are fully coupled. In this work, we formulate a chemo-mechanical model considering the two-way coupling between lithiation reaction and viscoplastic deformation in silicon nanoparticle anodes. Based on the model, the position of the lithiation interface, the interface velocity, and the lithiation-induced stresses can be solved simultaneously via numerical methods. The predicted interface velocity is in line with experimental measurements reported in the literature. We demonstrate that the lithiation-induced stress field depends on the lithiation reaction through two parameters: the migration velocity and the position of the lithiation interface. We identify a stress-mitigation mechanism in viscoplastic silicon anodes: the stress-regulated lithiation reaction at the interface serves as a “brake” to reduce the interface velocity and mitigate the lithiation-induced stresses, protecting the Si nanoparticle anode from being subjected to excessive mechanical stresses.

ABSTRACTA novel Mo/Al2O3spectrally selective solar absorber coating is deposited onto stainless steel (SS) substrates using magnetron sputtering method, which exhibits a high absorptance (α) of 0.90 and a low emittance (ε) of 0.08. In order to investigate the thermal stability, the SS/Mo/Al2O3coatings are annealed in air and vacuum at different temperatures. The surface morphology, microstructure, composition distribution, diffusion and optical properties before and after high-temperature annealing are characterised by scanning electronic microscopy (SEM), atom force microscopy (AFM), X-ray diffraction (XRD), micro-Raman spectroscopy, UV–vis spectrophotometer and emissometer. Experimental results indicate that the coatings are stable in air at 350°C. The values of solar absorptance and emittance below 350°C are 0.87–0.90 and 0.06–0.08, respectively. The coatings remain stable after annealed at 600°C in vacuum for 2 h with a good spectral selectivity (α/ε) of 0.89/0.06.

Abstract The stretchability of metal materials is often limited by the onset and development of necking instability. For instance, necking of lithium metal often occurs at low strains and thus hinders its practical applications in stretchable lithium batteries. Substrate/metal bilayers are emerging as a promising solution to the stringent stretchability requirement of metal electrodes and current collectors in flexible and stretchable batteries. So far, a comprehensive understanding of the bifurcation instability of substrate-supported metal layers under arbitrary biaxial in-plane tensile loading still remains elusive. Most existing theoretical and numerical studies of the bifurcation instability of substrate-supported metal layers assume either plane strain condition or single-necking mode (i.e., a single diffusive neck occurs). However, in conducted experiments, substrate/metal bilayers are subjected to uniaxial tensile loading and formation of multiple necks is observed during the tests. This paper presents an all-wavelength bifurcation analysis to understand the deformation instability of substrate/metal bilayers under arbitrary biaxial tensile loadings, from equi-biaxial tension, to plane-strain tension, and to uniaxial tension. Two representative bilayer structures are investigated, namely, a metal layer supported by a plastic substrate and a metal layer supported by an elastomer substrate. The analysis predicts three bifurcation modes of substrate/metal bilayers, including single-necking mode, multiple-necking mode, and surface mode. The results quantitatively demonstrate the bifurcation retardation effect of the supporting substrate: the stiffer/thicker is the substrate, the higher is the bifurcation limit. More importantly, it is further shown that there exists a theoretical upper bound of the bifurcation limit of a substrate/metal bilayer structure, which has not been reported before. Understandings from the present study may shed light on the optimal design of substrate/metal bilayer structures with enhanced deformability under complex biaxial loading conditions. [ABSTRACT FROM AUTHOR]

Abstract When inflating a rubber balloon, it is commonly concluded that a sudden expansion in balloon size (i.e., the burst) occurs once the inner pressure reaches a critical threshold, the instantaneous burst pressure. Such burst phenomena are usually attributed to the snap-through instability. In this work, we demonstrate that when a hydrogel balloon is subject to a subcritical pressure lower than the instantaneous burst pressure, the hydrogel balloon may remain stable for a span of time, and then burst suddenly. We refer to such burst phenomena as the delayed burst of the gel balloon. When subject to such a subcritical inner pressure, a hydrogel balloon slowly and continuously absorbs solvent and swells. We find the instantaneous burst pressure of the hydrogel balloon to be a decreasing function of swelling ratio. The criterion for the onset of burst is that the swelling-related instantaneous burst pressure drops to the applied inner pressure. The delayed burst can, therefore, be attributed to the time needed for the hydrogel swelling to reduce the instantaneous burst pressure to the level of applied pressure. We further delineate a map indicating three distinct deformation modes of gel balloons, i.e., instantaneous burst, delayed burst, and steady deformation without burst (safe mode), in the parameter space of applied pressure and mechanical properties of the hydrogel. The delayed burst of a hydrogel balloon is counterintuitive and a crucial aspect in developing hydrogel-shell-based soft actuators and soft machines. The research findings may shed light on the understanding of the complex failure mechanisms of hydrogel actuators and also facilitate the design of hydrogel-based tissue delivery capsules. [ABSTRACT FROM AUTHOR]

Surface charge density of nanopore walls plays a critical role in DNA capture in nanopore-based sensing platforms. This paper studied the effect of surface charge density on the capture of double-stranded (ds) DNA molecules into a polymer planar nanopore numerically and experimentally. First, we simulated the effective driving force (Feff) for the translocation of a dsDNA through a planar nanopore with different sizes and surface charge densities. Focus was given on the capture stage from the nanopore mouth into the nanopore by placing a rodlike DNA at the nanopore mouth rather than inside the nanopore. For negatively charged DNA and nanopore walls, electrophoretic driving force (FEP) under an electric field is opposed by the viscous drag force by electroosmotic flow (FEOF). As the surface charge density of the nanopore wall becomes more negative, FEOFexceeds FEPbeyond a threshold surface charge density, σthreshold, where DNA molecules cannot be driven through the nanopore via electrophoretic motion. For a 10 nm diameter nanopore filled with 1× TE buffer, σthresholdwas determined to be −50 mC/m2. The simulation results were verified by performing dsDNA translocation experiments using a planar nanopore with 10 nm equivalent diameter imprinted on three polymer substrates with different surface charge densities. Both fluorescence observation and ionic current measurement confirmed that only nanopore devices with the surface charge density less negative than σthresholdallowed DNA translocation, indicating that the simulated σthresholdvalue can be used as a parameter to estimate the translocation of biopolymers in the design of nanopore devices.

Designing capacitive force sensors with an enhanced and in situtunable sensitivity is important in many fields such as robotic grippers but has been challenging. Existing capacitive force sensors mainly rely on ingenious but complex structural designs, posing tremendous difficulty in fabrication and usually featuring a fixed sensitivity. We present a facile design of capacitive tactile force sensor with an enhanced and tunable sensitivity using electro-mechanically responsive dielectric elastomer as the sensing medium. Dielectric elastomer exhibits tunable mechanical properties when subject to voltage and pre-stretch: increasing voltage and pre-stretch level leads to a more compliant response to the external pressure. Effectively, the sensitivity of the dielectric elastomer sensor can be continuously increased over one order of magnitude by properly exerting voltage and pre-stretch to the dielectric elastomer tactile sensor.

Synthetic structural materials with exceptional mechanical performance suffer from either large weight and adverse environmental impact (for example, steels and alloys) or complex manufacturing processes and thus high cost (for example, polymer-based and biomimetic composites). Natural wood is a low-cost and abundant material and has been used for millennia as a structural material for building and furniture construction. However, the mechanical performance of natural wood (its strength and toughness) is unsatisfactory for many advanced engineering structures and applications. Pre-treatment with steam, heat, ammonia or cold rolling followed by densification has led to the enhanced mechanical performance of natural wood. However, the existing methods result in incomplete densification and lack dimensional stability, particularly in response to humid environments, and wood treated in these ways can expand and weaken. Here we report a simple and effective strategy to transform bulk natural wood directly into a high-performance structural material with a more than tenfold increase in strength, toughness and ballistic resistance and with greater dimensional stability. Our two-step process involves the partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3followed by hot-pressing, leading to the total collapse of cell walls and the complete densification of the natural wood with highly aligned cellulose nanofibres. This strategy is shown to be universally effective for various species of wood. Our processed wood has a specific strength higher than that of most structural metals and alloys, making it a low-cost, high-performance, lightweight alternative.

Dipolarization fronts (DFs), earthward propagating structures in the magnetotail current sheet characterized by sharp enhancements of northward magnetic field, are capable of converting electromagnetic energy into particle kinetic energy. The ions previously accelerated and reflected at the DFs can contribute to plasma flows ahead of the fronts, which have been identified as DF precursor flows in both the near‐equatorial plasma sheet and far from it, near the plasma sheet boundary. Using observations from the THEMIS (Time History of Events and Macroscale Interactions during Substorms) spacecraft, we show that the earthward particle and energy flux enhancements ahead of DFs are statistically larger farther away from the neutral sheet (at high latitudes) than in the near‐equatorial region. High‐latitude particle and energy fluxes on the DF dawnside are found to be significantly greater than those on the duskside, which is opposite to the dawn‐dusk asymmetries previously found near the equatorial region. Using forward and backward tracing test‐particle simulations, we then explain and reproduce the observed latitude‐dependent characteristics of DF precursor flows, providing a better understanding of ion dynamics associated with dipolarization fronts. Ions reflected from dipolarization fronts (DFs) contribute to the high‐latitude DF precursor flows near the plasma sheet boundary layerHigh‐latitude ion fluxes on DF dawnside are greater than those on duskside, which is opposite to the dawn‐dusk asymmetries near the equatorThe reversed dawn‐dusk asymmetry is caused by the nature of ion DF reflection and by ion dawnward accumulation in the ambient plasma sheet

Welding is one of the most important ways to connect metal materials. The mechanical properties of the welded joint are not uniform, which affects the overall strength of the joint. Through the traditional experimental method, it is difficult to test the mechanical properties of materials in different regions of welded joint. With 2219 aluminum alloy friction stir welding (FSW) joint as the research object, two kinds of micro sample methods, nanoindentation test and micro specimen tensile test, were respectively adopted for testing. Through these experimental studies, the mechanical properties of materials were obtained in different regions of welded joint: such as the elastic modulus, yield limit, ultimate strength and so on. The changes of the mechanical properties of the welded joint were analyzed from the weld center to the base metal. Through the data comparison, the results of the two kinds of micro test methods are basically consistent with each other. The elastic modulus in the center of the weld is relatively large, and decreases gradually with the transition to the base material. The yield limit and the ultimate strength in the center of the weld are relatively small, and increase gradually with the transition to the base material. The elongation is relatively high in the heat affected zone and relatively low in the weld zone and the base metal zone. These studies also provided the data basis for the research on the strength of welded joint.

Well-preserved cryptospore and chitinozoan assemblages were recovered from the Tierekawati Formation (late Katian, Late Ordovician) of the Mannan-1 borehole, south Tarim basin (Tarim Block), China. The chitinozoan assemblage is low in abundance and diversity (two genera, five species), and its age is restricted to the late Katian (Late Ordovician). The cryptospore assemblage consists of the tetrads (three genera, five species) and dyads (three genera, four species), with a low abundance and diversity. It has similarities to the previous records from the coeval deposits around the world. Comparison of two coeval cryptospore assemblages from two boreholes more than 300km apart within the Tarim Block shows the separate landmasses of the south and north Tarim Block were covered with much the same cryptophyte vegetation. The different elements in the vegetation might be caused by the local palaeogeography and palaeoenvironment.

This study aimed to explore the changes in phytochemical composition and inflammatory response of Camellia vietnamensisoil (CO) during refining. Four refined CO samples [degummed (DGO), deacidified (DAO), decolorized (DCO), and deodorized (DOO)] were prepared from crude CO (CCO). Five CO samples were measured for their composition of fatty acids, sterols, tocopherols, polyphenols, and oxidation products as well as anti-inflammatory activity in lipopolysaccharide (LPS)-induced THP-1 macrophages. The content of phytochemicals was significantly decreased with the deepening of the refining degree, especially after deacidification. CCO and DGO showed anti-inflammatory activity by inhibiting the production of pro-inflammatory cytokines and activation of NF-κB induced by LPS. Deacidification and decolorization of CO decreased its anti-inflammatory activity. The accumulation of oxidation products after deodorization in CO aggravated the inflammatory response. Trans-cinnamic, kaempferol, and protocatechuic acid in CO were crucial for their anti-inflammatory effects. These findings underlined that moderate refinement is suggested to retain its bioactive ingredients and anti-inflammatory ability.

To investigate the feasibility and clinical utility of a compressed-sensing-accelerated subtractionless whole-body MRA (CS-WBMRA) protocol with only contrast injection for suspected arterial diseases, by comparison to conventional dual-pass subtraction-based whole-body MRA (conventional-WBMRA) and available computed tomography angiography (CTA).

Rheum officinale, a member of the Polygonaceae family, is an important medicinal plant that is widely used in traditional Chinese medicine. Here, we report a 7.68-Gb chromosome-scale assembly of R. officinalewith a contig N50 of 3.47 Mb, which was clustered into 44 chromosomes across four homologous groups. Comparative genomics analysis revealed that transposable elements have made a significant contribution to its genome evolution, gene copy number variation, and gene regulation and expression, particularly of genes involved in metabolite biosynthesis, stress resistance, and root development. We placed the recent autotetraploidization of R. officinaleat ∼0.58 mya and analyzed the genomic features of its homologous chromosomes. Although no dominant monoploid genomes were observed at the overall expression level, numerous allele-differentially-expressed genes were identified, mainly with different transposable element insertions in their regulatory regions, suggesting that they functionally diverged after polyploidization. Combining genomics, transcriptomics, and metabolomics, we explored the contributions of gene family amplification and tetraploidization to the abundant anthraquinone production of R. officinale, as well as gene expression patterns and differences in anthraquinone content among tissues. Our report offers unprecedented genomic resources for fundamental research on the autopolyploid herb R. officinaleand guidance for polyploid breeding of herbs.

Recent experiments show that a thin film anode on a compliant substrate can significantly mitigate mechanical degradation and capacity fading of lithium-ion and sodium-ion batteries in service. The enhanced cycle performance of such a substrate-supported thin film anode is attributed to the wrinkling-induced stress relaxation. While the experimental evidence is suggestive, there lacks a systematic mechanistic study of the wrinkling of the substrate-supported thin film anode and its influence on anode cycle performance. We report a comprehensive study of the charging/discharging induced wrinkling formation and subsequent morphologic evolution of a substrate-supported thin film anode, using theoretical analysis and finite element simulations. We reveal that necking bands may form near wrinkling troughs or peaks and further develop to cause fragmentation of the anode over charging/discharging cycles, a failure mode not reported in the existing literature. The density and distribution of the wrinkling-associated necking bands in the substrate-supported thin film anode can be regulated by the substrate stiffness. Moreover, the wrinkling-induced necking in such a thin film anode can be deferred by regulating the charging capacity. These findings offer new mechanistic understanding of substrate-supported thin film anodes and thus shed light on novel design of high performance anodes in batteries.

Recent experiments and first-principles calculations show the two-step lithiation of amorphous silicon (a-Si). In the first step, the lithiation progresses by the movement of a sharp phase boundary between a pristine a-Si phase and an intermediate L i η Si phase until the a-Si phase is fully consumed. Then the second step sets in without a visible interface, with the L i η Si phase continuously lithiating to a L i 3 . 75 Si phase. This unique feature of lithiation is believed to have important consequences for mechanical durability of a-Si anodes in lithium ion batteries, however the mechanistic understanding of such consequences is still elusive so far. Here, we reveal an intrinsic stress mitigation mechanism due to elastic softening during two-step lithiation of a-Si, via chemo-mechanical modeling. We find that lithiation-induced elastic softening of a-Si leads to effective stress mitigation in the second step of lithiation. These mechanistic findings allow for the first time to quantitatively predict the critical size of an a-Si anode below which the anode becomes immune to lithiation-induced fracture, which is in good agreement with experimental observations. Further studies on lithiation kinetics suggest that the two-step lithiation also results in a lower stress-induced energy barrier for lithiation. The present study reveals the physical underpinnings of previously unexplained favorable lithiation kinetics and fracture behavior of a-Si anodes, and thus sheds light on quantitative design guidelines toward high-performance anodes for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Despite various Si-based anode designs proposed by different researchers, the low areal capacity of these anodes remains an obstacle to their utilization as they still fail to meet the requirements for commercial Li-ion batteries. To tackle this challenge, a novel design of pomegranate-inspired Si-C yolk-shell composite anodes was developed recently, where single silicon nanoparticles are encapsulated by conductive carbon shells with void spaces between particles and shells to accommodate expansion. Despite overall excellent cycling performance, lithiation halting and carbon shell pulverization are experimentally observed in some Si-C yolk-shell anode designs, which undermine the structural integrity and limit the battery performance. Quantitative understanding of these failure modes is still lacking despite being critical to improve the yolk-shell anode designs. We present a theoretical study on lithiation-induced stress field in Si-C yolk-shell composite anodes and its influence on lithiation kinetics and mechanical degradation. For the first time, it is demonstrated that the contribution of surface stresses to the lithiation-induced stress field in nano-sized silicon anodes is negligible. We identify promising designs to achieve full anode capacity without carbon shell fracture while reducing consumption of carbon material. Results from the present study may offer insight on improving designs of Si-C yolk-shell composite anodes.

Antidipolarization fronts (ADFs), tailward moving structures in the Earth's magnetotail with sharp decreases in their magnetic Bzcomponent, are thought to be mirror images of earthward propagating dipolarization fronts (DFs) generated on the opposite side of the reconnection site. We use ARTEMIS (Acceleration, Reconnection, Turbulence, and Electrodynamics of the Moon's Interaction with the Sun) observations and numerical simulations to study the role of ADFs in accelerating and reflecting ambient plasma sheet ions. In both case and statistical observations before ADF arrival, tailward streaming, energy‐dispersed ions are seen first. After about 1 min, the ion fluxes are enhanced significantly with the peak shifted duskward, and then the peak gradually shifts back to the tailward direction until the ADF arrives. All these signatures are reproduced by our simulation model of ion acceleration and reflection on ADFs. We further examine typical ion trajectories before and after ADF reflection, to understand these seemingly complicated ion signatures as well as their similarities with and differences from the DF preceding signatures. Ion distributions before ADF arrival are complicated and different from DF precursor signaturesSuch signatures are reproduced by simulation model of ion acceleration and reflection on ADFsSimilarities and differences between ADF and DF precursor signatures are discussed

Hydrometallurgy is a popular metallurgical technology. Filter press is common but vital to the production of hydrometallurgy. Hence, the process monitoring of filter press is of great significance for hydrometallurgy. Due to data analysis and related knowledge of filter press, Principal component analysis (PCA) is applied to process monitoring of the filter press via two traditional statistics. However, modeling and test data collected from actual production suffers from outliers, missing data, inconsistent sampling period between variables. Based on these practical problems, corresponding data proceeding technique is proposed. The final application simulation illustrates the validity of the proposed method.

Torsion applied to a slender soft rod can cause the rod to lose its stability and knot — a phenomenon widely referred to as the torsional instability of elastic rods. Previous studies mainly focus on predicting the critical load, at which the torsional instability occurs, and investigating the post-instability deformation of the rod. Thus far, little attention, if any, has been paid to exploiting the torsional instability of hyperelastic soft rods to realize functions such as actuation. In this work, we study the twisting process of hyperelastic soft rods through dimensional analysis and explicit finite element method, and find that the axial pulling force of the soft rod suddenly rises drastically immediately after the torsional instability occurs. Further simulations demonstrate that the sharply increased pulling force can be utilized to achieve a large-stroke pulling actuation. The influence of the rod geometry and material properties of the rod on the actuation forces/strains is also discussed. The results of this work are expected to guide the design of novel actuators based on the torsional instability of hyperelastic soft rods.

Seepage control is one of the important problems when designing a hydropower station. The upper reservoir of one hydropower station was built by excavation and backfill partly. Its impermeable program is the combination by concrete panel, geomembrane and vertical curtain. With the finite element method , the model of the dam has been built. The potential distribution of groundwater in the library on the seepage filed is analyzed. It also analyzes the seepage slope of dam body, dam foundation and reservoir and calculates the seepage discharge and replenishment at the situation of normal storage level. The results show that potential distribution law of reservoir seepage field is clear and definite. The effect of cutting water head by anti-seepage curtain and curtain downstream under protective layer at the bottom of the coarse sand and back packing drainage is remarkable. The panel and geomembrane have an effect on cutting waterhead. The seepage flow of upper reservoir is 488.16m3/d and the supply flow is 1019.52m3/d. So the control scheme of the upstream seepage is reasonable technically.

Supplier management is an important part of supply chain management, combined with the feature of the power industry, the paper design supplier comprehensive evaluation system of power grid enterprises, and put forward comprehensive green degree into supplier evaluation index system to conform to the national grid company production requirements. Firstly, according to the index system, the analytic hierarchy process evaluation method to draw the initial weights, secondly, the modification of entropy weight method to reduce the subjective factor influence on the evaluation results by AHP , finally, an example is given to demonstrate the feasibility of the evaluation index system for the power grid enterprise, it aslo provides a theoretical basis for decision-makers during the vendor selection.

Development of china's higher education is shifting from the connotation construction of the expansion, As colleges and universities, In order to meet the needs of the national education strategy, Comprehensive reform must start from the professional, This article from a regional university to build a professional cooperation, The perspective of building experimental zone for comprehensive reform of professional studies.

More and more countries are focusing on the lack of resources with the consumption of large quantities of fossil energy. The Chinese government is actively promoting the policies related to the transformation of the energy structure which will increase the proportion of clean energy consumption and reduce the proportion of fossil energy consumption in order to relieve the pressure on domestic energy. Interest in the generation of biogas from agricultural residues is increasing rapidly due to its climate benefits. This article is committed to analysis the economic performance of the biogas cogeneration energy supply system of livestock and poultry breeding plants in southern China. The model of the biogas cogeneration energy supply system of livestock and poultry breeding plants in southern China and the advices to the government will also been proposed as a result. According to the results, biogas cogeneration system is feasible in economy with reasonable device configuration and operating strategy.

Jiedu Huoxue Decoction (JHD), a recommended traditional prescription for patients with severe COVID-19, has appeared in the treatment protocols in China. Based on bioinformatics and computational chemistry methods, including molecular docking, molecular dynamics (MD) simulation, and Molecular Mechanics Generalized Born Surface Area (MM/GBSA) calculation, we aimed to reveal the mechanism of JHD in treating severe COVID-19. The compounds in JHD were obtained and screened on TCMSP, SwissADME, and ADMETLab platforms. The compound targets were obtained from TCMSP and STITCH, while COVID-19 targets were obtained from Genecards and NCBI. The protein-protein interaction network was constructed by using STRING. Gene Ontology (GO) and KEGG enrichment were performed with ClueGO and R language. AutoDock vina was employed for molecular docking. 100 ns MD simulation of the optimal docking complex was carried out with AmberTools 20. A total of 84 compounds and 29 potential targets of JHD for COVID-19 were collected. The key phytochemicals included quercetin, luteolin, β-sitosterol, puerarin, stigmasterol, kaempferol, and wogonin, which could regulate the immune system. The hub genes included IL6, IL10, VEGFA, IL1B, CCL2, HMOX1, DPP4, and ACE2. ACE2 and DPP4 were related to SARS-CoV-2 entering cells. GO and KEGG analysis showed that JHD could intervene in cytokine storm and endothelial proliferation and migration related to thrombosis. The molecular docking, 100 ns MD simulation, and MM/GBSA calculation confirmed that targets enriched in the COVID-19 pathway had high affinities with related compounds, and the conformations of the puerarin-ACE2, quercetin-EGFR, luteolin-EGFR, and quercetin-IL1B complexes were stable. In a word, JHD could treat COVID-19 by intervening in cytokine storm, thrombosis, and the entry of SARS-CoV-2, while regulating the immune system. These mechanisms were consistent with JHD's therapeutic concept of “detoxification” and “promoting blood circulation and removing blood stasis” in treating COVID-19. The research provides a theoretical basis for the development and application of JHD.

To explore the deepest regions of the ocean with high flexibility and environmental adaptability, deep-sea soft robots have been developed recently. One prominent example is the self-powered soft robot that successfully operated in the Mariana Trench at a depth of 11,000 meters. Notably, many functional electronic components such as resistive elements, capacitors, and crystal oscillators may fail under extreme hydrostatic pressure, posing significant challenges for the practical massive deployment of deep-sea soft robots. Consequently, designing miniature pressure vessels on the printed circuit board to protect these vulnerable electronic components is vital for enhancing the reliability of deep-sea soft robots. However, traditional structure design methods – which often rely on theoretical analysis, experimental testing and numerical simulations – are often costly and time-consuming, especially for design problems in high-dimensional design spaces. Herein, we demonstrate a machine-learning-accelerated design method for devising miniature pressure vessels for vulnerable electronic components in deep-sea soft robots. Machine learning algorithms including decision trees and neural network models are employed and compared. The resulting design algorithm can predict whether a specific design can survive the deep-sea hydrostatic pressure with high accuracy in ∼0.35 ms, roughly seven orders of magnitude faster than traditional design methods.

The water soluble grinding fluids (coolants) with 3MTM TrizactTM Diamond Tile（TDT）used in thinning process of the flat glass contains lubricants, extreme pressure antiwear agents, surfactants and anti-rust additives, which are expected to provide the functions of lubricating, cooling, cleaning, anti-rust. The results showed that the water soluble grinding fluids can improve the processing performance of 3M TDT effectively, keep excellent self-sharpening, increase processing efficiency, extend the service life of the abrasive pads and reduce surface roughness of the glass .

Accurate detection of the direction of hydraulic fracturing cracks in the oil field is one of the crucial factors in rational exploitation of the remaining oil and enhanced oil recovery. In this paper, using the potential and the potential gradient test methods and virtual instrument technology, we design and develop an intelligent borehole-surface electrical method multi-parameters detection system (BEMDS), which can achieve multi-channel, multi-parameter and high-precision borehole-surface electrical method data acquisition. Joint programming technology of Labview and Matlab gains the simultaneously measurement of the parameters of resistivity and induced polarization. As a result, the drawbacks of the original instrument that measuring single parameters and cannot mutually authenticate has been overcome.

Interfacial instability is a fundamental issue in heterostructures ranging from biomaterials to joint replacement and electronic packaging. This challenge is particularly intriguing for lithium ion battery anodes comprising silicon as the ion storage material, where ultrahigh capacity is accompanied by vast mechanical stress that threatens delamination of silicon from the current collectors at the other side of the interface. Here, we describe Si-beaded carbon nanotube (CNT) strings whose interface is controlled by chemical functionalization, producing separated amorphous Si beads threaded along mechanically robust and electrically conductive CNT. In situtransmission electron microscopy combined with atomic and continuum modeling reveal that the chemically tailored Si–C interface plays important roles in constraining the Si beads, such that they exhibit a symmetric “radial breathing” around the CNT string, remaining crack-free and electrically connected throughout lithiation–delithiation cycling. These findings provide fundamental insights in controlling nanostructured interfaces to effectively respond to demanding environments such as lithium batteries.

Using self-designed indoor detecting methods, the performance test of shotcrete doped compound admixture and crude fiber were carried out. The results showed that compound admixture and crude fiber can improve the compressive strength, flexural toughness and crack resistance of shotcrete. Axial bond strengths of shotcrete with rock were more than 1.0MPa, and that can be increased by combined-doped compound admixture and crude fiber. Rebound rates of shotcrete were 23% and 20%, layer thickness in one shot cycle were 22cm and 25cm, and combined-doped compound admixture and fiber can increase the cohesiveness and reduce rebound rate. Self-designed methods can be used to compare construction performance of different shotcretes.

The energy gradually become the mainstream of the development of the new century automobile. Worsen environmental problems and increases nervous energy issues forcing people to continue to seek a clean alternative fuels, in order to improve the traffic situation. Energy to become the focus of attention of Governments and car manufacturers. People have spared no effort to carry out energy vehicles.