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This article aims at experimentally investigating a cycle behaviour of a new lateral force-resisting structural system, that is, precast composite walls with ecological filled blocks. For this purpose, a total of five low cyclic loading tests were conducted for the 1:2-scaled precast composite wall specimens with five different kinds of ecological filled blocks, namely, the wheat straw fibre raw soil–based block, the recycled expanded polystyrene lightweight concrete block, the wheat straw fibre cement–based block, the autoclaved aerated concrete block and the cotton straw block. In the test, the failure patterns, hysteretic loops, characteristic points, skeleton curves, ductility and relative deformation, stiffness degradation and energy dissipation capacity of the tested specimens were obtained and further analysed. The test results show that (1) the failure modes and mechanisms of the tested specimens are primarily affected by the strength of the filled blocks and the connection performance of the concrete ribbed grids; (2) the filled blocks, ribbed grids and the concealed frame can work cooperatively and interact and they play roles in the three stages of elastic, elastic–plastic, and ultimate destruction in turn; (3) the compressive strength, crack resistance, modulus of elasticity of filled blocks and bonding capacity with the ribbed grids are the main factors affecting the characteristic point, displacement ductility, stiffness degradation and other seismic performance index of the precast composite wall; (4) the five wall specimens have different energy dissipation capacities with the increase of displacement and also have the strong ability to resist collapse, which reflect the precast composite walls' good behaviour in terms of earthquake resistance. [ABSTRACT FROM AUTHOR]

This study investigated the mechanical and thermal properties of glass fibre-reinforced ceramsite-foamed concrete with a volume of entrained air generated by hydrogen peroxide. The effects of hydrogen peroxide content, glass fibre content, glazed hollow bead content and ceramsite content on the compressive strength, splitting tensile strength and thermal conductivity were investigated. The results indicated that with the addition of hydrogen peroxide and an increase in glazed hollow bead and ceramsite content, there was a significant increase in the brittleness of foamed concrete. Glass fibre can obviously improve the splitting tensile strength and reduce the thermal conductivity of foamed concrete. In addition, an empirical compressive strength formula of glass fibre-reinforced ceramsite-foamed concrete was recommended. [ABSTRACT FROM AUTHOR]

We report a facile and general approach for the synthesis of boron nitride nanosheet (BNNS)–metal nanoparticle (NP) composites at room temperature without adding any reducing agent. BNNS was exfoliated in hydroxide aqueous media using tip-sonication. The resulting BNNS possessed abundant hydroxyl groups which reduced the gold salt and enabled the in situ growth of uniform Au NPs on BNNS (average diameter of 17 nm). The as-synthesised BNNS–Au NP composite exhibited outstanding catalytic and electrocatalytic activities which were confirmed by its excellent performance in the chemical degradation of Rhodamine B and electrocatalytic oxidation of hydrazine, respectively. This method was also demonstrated to be a general approach for the preparation of other BNNS–metal NP composites by the in situ growth of Ag, Pd and Pt NPs on BNNS. [ABSTRACT FROM AUTHOR]

P-type Bi[sub 0.48]Sb[sub 1.52]Te[sub 3] alloys added with WSe[sub 2] were achieved via the zone melting method. The electrical performance was improved due to the increased carrier concentration, while the lattice thermal conductivity was simultaneously decreased, mainly due to the numerous types of nanoprecipitates produced, such as the second phase, antisite substitution and interfaces with different scales. As a result, a 23% improvement in the thermoelectric figure of merit zT was obtained with the addition of WSe[sub 2], making these composites more attractive for commercial applications. [ABSTRACT FROM AUTHOR]

Introduction: Unilateral condylar hyperplasia (UCH) is a progressive, nonneoplastic overgrowth of the condyle of the temporomandibular joint. For treating active UCH, a popular method combines orthognathic surgery with high condylectomy and orthodontic treatment. The goal of this study was to introduce a new method to correct asymmetry for active UCH.Methods: Retrospectively, 47 patients with active UCH were divided into horizontal-type, vertical-type, and combined-type. All patients were treated with condylectomy plus postsurgery standard orthodontics (CPSO) with applied miniscrews implanted in infrazygomatic crest and hard palate to intrude affected side of maxillary molars and apply intermaxillary traction for contralateral molars. Cone-beam computed tomography was taken at presurgery, postsurgery, and the end of orthodontics (T3).Results: In the vertical (n = 10) and combined (n = 28) types, deviation of the chin and the canting of the mandible and maxillary occlusal plane were significantly reduced at T3. A difference in the torque of bilateral maxillary first molar (U6) and bilateral mandibular first molar (L6) was significantly reduced at T3. The anterior, superior, and posterior joint spaces in the vertical-type and combined-type were significantly decreased at T3 compared with postsurgery. In contrast, in the horizontal-type group (n = 9), the deviation of the chin was corrected; however, the canting of the mandible and maxillary occlusal plane was significantly increased at T3 compared with presurgery.Conclusions: CPSO restored facial and occlusal symmetry for vertical-type and combined-type active UCH and returned affected-side condyle to the glenoid fossa. However, CPSO was not suitable for treating the horizontal-type UCH. [ABSTRACT FROM AUTHOR]

The macro- and micro-physical properties of cement-stabilized steel slag (CSS) base materials in a highway project were studied. A discrete element model of CSS with a real steel slag shape was constructed using Particle Flow Code 3D and 3D scanning technology. The sensitivity between the macro- and micro-parameters of the sample was explored, and a nonlinear regression equation was established to analyze the relationship between these parameters. Uniaxial compression simulation tests were conducted on CSS with steel slag contents of 0%, 10%, 30%, and 50%. By combining contact calculation, crack location, energy tracking, acoustic emission (AE) monitoring, and other program systems, the macro- and micro-mechanical properties and micro-crack evolution law of the samples in the failure process were analyzed in terms of strength, energy, and fracture damage. The damage mechanism of CSS was also revealed. Results showed that with the increase in steel slag content, the elastic modulus and peak stress of the samples increased, the Poisson's ratio decreased, and the post-peak stress curve steepened, indicating obvious brittle failure characteristics. With the increase in steel slag content, the crack initiation stress, thickness of the fracture surface, and number of internal micro-cracks in CSS increased exponentially. In the uniaxial compression test, AE intensity underwent five stages, in which the peak moment of AE intensity exhibited hysteresis compared with the moment of the peak stress. Absorption and release phenomena of strain energy were observed in the process of specimen failure. When the steel slag content increased, the total strain energy absorbed by the specimen increased. When the absorbed energy exceeded the bond strength, the bond ruptured with the release of energy. The main crack of the sample penetrated and stretched to the direction of strain energy release to form a macroscopic fracture surface. [Display omitted] • The discrete element model of materials is established by 3D scanning technology. • Porosity is an important factor affecting the mechanical properties of samples. • The crack initiation stress increases from the increase in steel slag content. • There is a hysteresis between acoustic emission event peak and stress peak. • The root cause of material failure is the absorption and dissipation of energy. [ABSTRACT FROM AUTHOR]

Lithium-ion migration at the WO 3 /electrolyte interface is governed by the phase transformation mechanism by which metastable states are replaced from one phase to another. Herein, an in situ single nanowire-based cell is constructed to investigate the dynamic phase transformation and morphology evolution of h-WO 3 nanowire in real-time during its deep lithiation. One of the most significant features of h-WO 3 lithiation is the irreversible transformation from h-WO 3 to Li 2 WO 4. There are a large number of deep ion-trapping sites composed of 4 O atoms in Li 2 WO 4 crystal structure, that is, inserted lithium ions are irreversibly bound in these traps and nearly cannot be deintercalated. A mechanism on irreversible WO 3 -to-Li 2 WO 4 transformation in deep lithiation reaction is demonstrated. With the aid of in situ transmission electron microscopy, we controllably triggered lithium-ion migration at the WO 3 /electrolyte interface and directly visualized the nanoscale lithium-ion migration as a stop motion movie. Hexagonal WO 3 irreversible transformation to Li 2 WO 4 can be experimentally demonstrated via in situ HRTEM in the deep lithiation process including the initial activation of the lithium metal, the wetting of a single WO 3 nanowire and the migration of lithium ions into WO 3 , and the restructuring of hexagonal WO 3. [Display omitted] [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3) usually fractures in the brittle form, and achieving large plastic deformability to avoid catastrophic failure is in high demand. Here, ε‐Ga2O3 thin films with columnar crystals and partial unoccupied Ga sites are synthesized, and it is demonstrated that the ε‐Ga2O3 at the submicron scale can be compressed to an ultra‐large plastic strain of 48.5% without cracking. The compressive behavior and related mechanisms are investigated by in situ transmission electron microscope nanomechanical testing combined with atomic‐resolution characterizations. The serrated plastic flow and large strain burst are two major deformation forms of ε‐Ga2O3 during compression, which are attributed to the dislocation nucleation and avalanches, formation of new grains, and amorphization. The ultra‐large compressive plasticity of ε‐Ga2O3 thin films at the submicron scale can inspire new applications of Ga2O3 in micro‐ or nano‐ electronic and optoelectronic devices, especially those that require impact resistance during processing or service. [ABSTRACT FROM AUTHOR]

This paper presents an experimental investigation into shockwave and flame characteristics of compressed hydrogen released through various types of pressure relief devices (PRDs) for which data have not been previously reported. Burst disks and safety valves with different set pressure (P0) of 22–140 MPa were tested. Shockwave intensity/velocity spontaneous ignition/flame behavior was monitored by in-situ pressure/light sensors, respectively. Previous works have mostly focused on burst disks with low P0 (under 10 MPa), leaving safety valves and high-pressure burst disks uninvestigated. It was found that shockwave/spontaneous ignition behavior differs with PRD types. Spontaneous ignition occurs in all burst disk cases, along with an ignition/self-extinguishment/reignition process with relatively low P0, which has not been revealed previously. In contrast, none of the safety valves cause spontaneous ignition, resulting from the absence of shockwave due to lower overpressure values/rise rate during release. This suggests that shockwave formed by sudden release is the most dominant factor in spontaneous ignition. Also, the occurrence of self-extinguishment does not guarantee the absence of jet flame. This work provides a comprehensive database revealing shockwave and flame characteristics of hydrogen released through different PRDs, which offers basic data and theoretical support for the safety and risk assessment of high-pressure hydrogen facilities. [ABSTRACT FROM AUTHOR]

• The liquid film spreading width for the superhydrophilic tube is two times higher than that of plain surface and little relevance to spray density. • The increment of flow rate leads to the increase in frequency of the impacting droplet instead of droplet volume. • The periodic behavior of liquid film fluctuation in droplet mode was observed. Falling film on horizontal tube banks is widely used in heat transfer exchangers and absorbers due to its high heat and mass transfer performance. The superhydrophilic surface can effectively ameliorate the wettability of the tube wall and maintain thin film even at a very low spray density. Both of them play the dominating role in heat and mass transfer process. In this paper, a thermal tracing method was employed to investigate the liquid spreading feature and film fluctuation characteristics over a horizontal superhydrophilic tube. The results showed that the liquid film spreading width for the superhydrophilic tube was two times higher than that of the plain surface. Interestingly, as the liquid film extended continuously along the tube surface, the spreading width exhibited little relevance to the spray density under the current experimental condition for the superhydrophilic tube. Furthermore, in the case of droplet mode, the increment of flow rate leaded to an increase in the frequency of the impacting droplet instead of the droplet volume. Finally, the periodic behavior of liquid film fluctuation in droplet mode was observed as well, which demonstrated higher fluctuation intensity than that of other flow modes. The superhydrophilic-aided drop mode is of value in exploring the efficient, precise, and feasible technique for falling liquid film on a horizontal tube especially for ultralow spray density. [ABSTRACT FROM AUTHOR]

Owing to the accumulation of trapped ions in host structures, electrochromic devices (ECDs) suffer from diminished optical modulation and reduced device efficiency under long-term charge insertions and extractions. The accumulation of trapped ions also results in structural changes and mechanical degradation of the electrochromic film, for which very few studies are currently on hand. Here, we report on an explorative study about the mechanical degradation for a WO 3 -based monolithic ECD: glass/ITO/WO 3 /LiClO 4 (PEO)/TiO 2 /ITO/glass. For the WO 3 EC film, both the electrochemical degradation from cyclic voltammetry and the volume expansion by in-situ AFM monitoring were studied. Under the collective effects of these two aspects, the mechanical degradation process of the ECD was recorded through surface morphology evolutions of the WO 3 film during life cycling of the ECD to its final failure for up to 90 000 cycles. The surface morphology of the WO 3 film underwent three stages: (I) it first became increasingly denser and denser when the cycles were low, approximately 10 000 times; (II) when the cycles went up to 30 000 times or more, the surface of the WO 3 film had an uneven distribution, with some dense islands surrounded by loose areas; and (III) when the cycling continued, this situation got worse, and finally, the WO 3 film started to crack. This exploration provides new insights into the degradation mechanism of WO 3 -based ECDs upon repetitive insertions and extractions of Li ions in practical use. • The ratio Q ex /Q in decreased from an original 54 % to the final 23 % after 1200 cycles at a higher rate than both Q ex and Q in. • A ratio of 5.8 % of the volume expansion for the deeply-colored WO 3 film was in-situ observed. • Mechanical degradation process of the ECD was first recorded through surface morphology evolution of the WO 3 films. • The surface morphology evolution showed three stages: first densification, uneven distribution and final cracking. [ABSTRACT FROM AUTHOR]

In this letter, an n+/p junction on a germanium substrate, formed by phosphorous implantation and subsequent laser thermal annealing process, is demonstrated. The effects of laser energy fluence and irradiation pulse number on the redistribution of dopant atoms have been investigated. The secondary-ion-mass-spectrometry results indicate that steplike dopant profiles are formed with dopant atoms extending deeper upon increased laser energy fluence and successive pulse number. After being irradiated at a laser energy fluence of 0.16 J/cm2 with two successive pulses, the junction exhibits a sheet resistance of ∼50 Ohm/sq for n+ region, a comparable current-voltage characteristic, and much less phosphorus dopant diffusion in comparison with those formed by rapid thermal process annealing. [ABSTRACT FROM AUTHOR]

BaCe 0.7 Zr 0.1 Y 0.1 Yb 0.1 O 3-δ (BCZYYb) is one of the most popular electrolyte materials in proton ceramic fuel cells (PCFCs). The synthesizing method and properties of BCZYYb powders have a significant impact on the sintering activity of electrolyte materials. In this work, the BCZYYb electrolyte was synthesized by ammonium bicarbonate co-precipitation method (CPT), and was compared with the powder produced by solid-state reaction (SSR) and sol-gel (SG) methods. XRD results show the BCZYYb powder synthesized by the CPT method belongs to orthorhombic crystal system with a space group of Pmcn (No. 62) and the refined lattice parameters are a = 8.774 Å, b = 6.173 Å, and c = 6.203 Å. In humid air atmosphere, the total conductivity at 650 °C and the activation energy for the BCZYYb powder prepared via the CPT method was 2.1 × 10−2 S cm−1 and 0.46 eV, respectively, as compared with 1.9 × 10−2 S cm−1 and 0.45 eV for the SSR method, and 1.8 × 10−2 S cm−1 and 0.44 eV for the SG method. Under similar testing conditions, the measured peak power densities were 0.51, 0.35, and 0.40 W cm−2 at 650 °C for the anode supported PCFCs using electrolyte powder prepared via CPT, SSR and SG methods, respectively, which proves the CPT method is an effective and viable route for PCFCs applications. • BCZYYb powders are successfully prepared by CPT, SG, and SSR methods. • The CPT method shows better conductivity and performance than the other methods under similar testing conditions. • A 600-h test showed the cell with electrolyte prepared by the CPT method has a good long-term stability. [ABSTRACT FROM AUTHOR]

Achieving simultaneous control over multiple functional properties, such as magnetic anisotropy, magnetoresistance, and metal-insulator transition, with atomic precision remains a major challenge for realizing advanced spintronic functionalities. Here, we demonstrate a unique approach to cooperatively tune these multiple functional properties in highly strained La0.7Sr0.3MnO3 (LSMO) thin films. By inserting varying perovskite buffer layers, compressively strained LSMO films transition from a ferromagnetic insulator with out-of-plane magnetic anisotropy to a metallic state with in-plane anisotropy. Remarkably, atomic-scale control of the buffer layer thickness enables precise tuning of this magnetic and electronic phase transformation. We achieve a colossal magnetoresistance tuning of 10,000% and an exceptionally sharp transition from out-of-plane to in-plane magnetic anisotropy within just a few atomic layers. These results demonstrate an unprecedented level of control over multiple functional properties, paving the way for the rational design of multifunctional oxide spintronic devices. [ABSTRACT FROM AUTHOR]