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For high-power piezoelectric ceramics to operate stably under high alternating electric fields, they require co-high values of the piezoelectric coefficient (d33), mechanical quality factor (Qm), and Curie temperature (Tc). Here, 0.04Pb(Mn1/3Nb2/3)O3-0.96Pb(Zr0.505Ti0.495)O3-0.005Fe2O3-0.002Sc2O3 (ceramic 1)has a tetragonal phase near the piezoelectric morphotropic phase boundary, which significantly improved the Qm value of the ceramic while maintaining high d33 and Tc. It exhibits advantages in multi-parameter co-high values, with d33 = 340 pC/N, dielectric loss tanδ = 0.24%, Qm = 2200, electromechanical coupling coefficient (kp) = 0.59, permittivity (εr) = 1450 and Tc = 377 °C. The figure of merit (FOM = Qm × d33) value of ceramic 1 is as high as 748 nC/N at room temperature, surpassing most high-power piezoelectric ceramics. Under an alternating electric field of 40 V/mm at 92 kHz, the ceramic achieves a vibration velocity of 0.4 m/s, which is 3.6 times higher than that of commercial piezoelectric ceramic under the same electric field. These results indicate that the ceramic 1 is highly suitable for advanced high-power piezoelectric applications. [ABSTRACT FROM AUTHOR]

In this study, the Lewis doping approach of polyaniline (PANI) was employed to fabricate cobait–nitrogen–carbon (Co-N-C) oxygen electrocatalysts for Zn–air batteries, aiming to enhance the active spots of Co-N-C. This resulting Co-N-C catalysts exhibited well-defined nanofiber networks, and the Brunauer-Emmett-Teller (BET) analysis confirmed their substantial specific surface area. Electrochemical experiments demonstrated that the Co-N-C catalysts achieved the half-wave potential (vs. RHE) of 0.85 V in alkaline medium, overcoming Pt/C and iron–nitrogen–carbon (Fe-N-C) counterparts in extended cycle testing with only a 25 mV change in a half-wave potential after 5000 cycles. Remarkably, the highest power density measured in the zinc (Zn)–air battery reached 227 mW/cm2, a significant improvement over the performance of 101 mW/cm2 of the platinum on activated carbon (Pt/C) catalyst. These findings highlight the advantageous stability enhancement associated with the utilization of Co in the Co-N-C catalysts. [ABSTRACT FROM AUTHOR]

Direct hydrogen production from inexhaustible seawater using abundant offshore wind power offers a promising pathway for achieving a sustainable energy industry and fuel economy. Various direct seawater electrolysis methods have been demonstrated to be effective at the laboratory scale. However, larger-scale in situ demonstrations that are completely free of corrosion and side reactions in fluctuating oceans are lacking. Here, fluctuating conditions of the ocean were considered for the first time, and seawater electrolysis in wave motion environment was achieved. We present the successful scaling of a floating seawater electrolysis system that employed wind power in Xinghua Bay and the integration of a 1.2 Nm3 h−1-scale pilot system. Stable electrolysis operation was achieved for over 240 h with an electrolytic energy consumption of 5 kWh Nm−3 H2 and a high purity (>99.9%) of hydrogen under fluctuating ocean conditions (0~0.9 m wave height, 0~15 m s−1 wind speed), which is comparable to that during onshore water electrolysis. The concentration of impurity ions in the electrolyte was low and stable over a long period of time under complex and changing scenarios. We identified the technological challenges and performances of the key system components and examined the future outlook for this emerging technology. Seawater electrolysis shows promising potential toward sustainable energy generation, but large-scale in-situ demonstrations are still lacking. Here, authors report a floating platform integrating a 1.2 Nm3h−1 seawater direct electrolysis system with wind power for energy input in the Xinghua Bay. [ABSTRACT FROM AUTHOR]

In this work, the 0.04Pb(Zn1/3Nb2/3)O3-0.05Pb(Mn1/3Sb2/3)O3–xPbZrO3–(0.91−x)PbTiO3 + ymol%Fe2O3 (xPZ-PZNMST + y%Fe; x = 0.440–0.460, y = 0.00–0.15) piezoelectric ceramics were synthesized by solid-state reaction method. The 0.45PZ-PZNMST + 0.10%Fe ceramic with morphotropic phase boundary shows optimum comprehensive electromechanical properties with d33 = 401 pC/N, kp=0.6, tan δ = 0.39%, Qm=921, and Tc = 314 °C. In addition, a low high-field tanδ of 0.78% at 200 V/mm is achieved in the 0.45PZ-PZNMST + 0.10%Fe ceramic. Therefore, a high vibration velocity of 0.80 m/s is obtained in 0.45PZ-PZNMST + 0.10%Fe ceramic. The maximum mechanical energy density of 0.45PZ-PZNMST + 0.10%Fe ceramic reaches 2500 J/m3, which is about four times that of commercial PZT4 ceramics (620 J/m3). The 0.45PZ-PZNMST + 0.10%Fe ceramic with good high-power performance shows a potential application in high-power ultrasonic transducers. [ABSTRACT FROM AUTHOR]

Hydraulic asphalt concrete (HAC), extensively employed in impervious structures of embankment dams, typically experiences dynamic compression-shear loads during service with limited studies. By utilizing a servo-hydraulic test device, this study investigated the dynamic compression-shear behaviors of HAC under four strain rates (10–5/s, 10–4/s, 10–3/s and 10–2/s) and five axial compressive stresses (0 MPa, 0.25 MPa, 0.5 MPa, 0.75 MPa and 1 MPa) and explored the associated failure modes and stress–strain curves. Corresponding to axial stresses of 0 MPa and 1 MPa, peak shear stresses were determined to be 0.41 MPa and 1.25 MPa at 10–5/s, and 0.74 MPa and 1.98 MPa at 10–2/s. Peak shear stresses were found to be increased by factors of 3.05 and 2.67 influenced by axial compressive stress. Enhancements of 180% and 158% were observed in peak shear stresses, attributed to the strain rate effect. Based on the Mohr–Coulomb criterion, the compressive-shear strength of HAC comprises the cohesion strength of asphalt matrix and the interfacial adhesion strength between aggregates and asphalt. Moreover, effects of axial stress and strain rate on failure mechanism were illustrated. The failure criteria of HAC under compression-shear stresses were introduced based on the principal stress, octahedral stress and stress invariant. The investigation provides both theoretical and experimental insights for the applications of HAC in hydraulic structures. [ABSTRACT FROM AUTHOR]

Integrated nanoelectromechanical systems (NEMS) with nm-scale piezoelectric films exhibit enormous advantages compared with traditional microelectromechanical systems. Herein, the flexible PZT ferroelectric films with 50–200 nm thickness were achieved, and their piezoelectric d33 rapidly enhanced with the thickness of film increasing and the thickness of mica substrate decreasing. The d33 value of the 80 nm-thick PZT film increases from 180 to 220 pC/N with the thickness of mica substrate reducing from 0.2 mm to 10 μm to largely decrease clamping strain between substrate and PZT film. Furthermore, the flexible mica substrate largely increases both the piezoelectric effect and the inverse piezoelectric effect of PZT films. These nm-scale PZT films with robust piezoelectricity will encourage the creation of new NEMS and piezoelectric devices that are flexible. [ABSTRACT FROM AUTHOR]

In recent years, non-noble metal catalysts such as Fe–N–C have received a lot of interest due to their excellent oxygen reduction (ORR) activity. However, the active sites of Fe–N–C still need to be further improved. Here, by adopting Lewis doping and double nitrogen source strategies to increase the density of accessible active sites, the catalyst exhibits excellent ORR activity. The ORR half-wave potential (E1/2) in 0.1 mol/L KOH solution can reach 0.92 V (vs. RHE), and the maximum power density of the Zn–air battery with Fe–N–C@MA-950 as the air electrode can reach 220 mW cm−2. The strategies provide a novel approach to the design of carbon-based catalysts for efficient energy conversion. [ABSTRACT FROM AUTHOR]

Renal cancer is a common malignancy of the urinary system, and renal clear cell carcinoma (RCCC) is the most common pathological type. Transmembrane channel-like (TMC) protein is an evolutionarily conserved gene family containing 8 members, however there is still a lack of comprehensive analysis about TMC family members in RCCC. In this study, we analyzed the expression of TMC family members in RCCC from TCGA and investigated the prognosis values and immune infiltration of TMC family members in RCCC. We found that TMC2, TMC3, TMC5, TMC7 and TMC8 were significantly related with overall survival (OS) of RCCC patients. TMC3, TMC6, and TMC8 was positively correlated with the degree of immune infiltration in RCCC. TMC2, TMC6, TMC7, and TMC8 were positively correlated with immune checkpoint genes, whereas TMC4 was negative. According to KEGG and GO analysis, almost all TMCs except TMC4 were involved in the immune response. Thus, we may regard the TMC family members as novel biomarkers to predict potential prognosis and immunotherapeutic response in RCCC patients. [ABSTRACT FROM AUTHOR]

High-power ultrasonic transducers need piezoelectric ceramics with a high piezoelectric coefficient, d33, high quality factor, Qm, large coercivity field, EC, high Curie temperature TC , etc, so that they can work in a high electric field for a long time. Here, 0.04Pb (Mn1/3Nb2/3) O3–0.96Pb (Zr0.515Ti0.485) O3-xmol%Nb2O5 (PMN–PZT-x%Nb2O5, x = 0.0–1.0) ceramics with high piezoelectric performance and cost-effective merits were prepared using low-cost industry-grade raw materials. The PMN–PZT-0.6%Nb2O5 ceramic shows the optimal comprehensive electrical properties, such as a high d33 of 411 pC/N, a Qm of 653, a dielectric loss tanδ of 0.30%, a relative permittivity εr of 1457, an electromechanical coupling factor kp of 0.58, a high TC of 355°C, and a large EC of 1.3 kV/mm. Under the electric field of 100 V/mm, the PMN–PZT-0.4%Nb2O5 ceramic shows a large vibration velocity of 0.9 m/s. Since PMN–PZT-x%Nb2O5 ceramics have the merits of high quality, high-cost performance ratio, and easy mass production, they are promising for applications of high-power devices. [ABSTRACT FROM AUTHOR]

The computer-aided design (CAD) models contain abundant domain knowledge, either structure, material, or process information. An efficient retrieval ability for these reusable design resources will provide designers invaluable support for efficient product development. With this goal, this paper proposed a novel CAD model retrieval framework based on correlation network and relevance ranking. First, a multi-layer network was constructed to express the high-level local correlation between CAD models. Then, the global shape comparison method is employed to determine the CAD models most similar to the query, called the relevant subset. Finally, the relevance ranking based on the Bayesian theory can be performed by analyzing the correlation between the relevant subset and other CAD models. The relevance probability determines which CAD model is the most relevant to the query, and the ranking list can be finally obtained. Experimental results and comparisons with state-of-the-art methods demonstrate the superiority and user-friendliness of the proposed method. [ABSTRACT FROM AUTHOR]

The final closure of oceans in accretionary orogens is a transformative process for continental crustal growth. The geodynamic mechanism is still controversial. This study synthesizes the Permo-Carboniferous tectono-stratigraphy, detrital zircon U–Pb dating and magmatism in the Junggar terranes to determine their interlinkage during ocean closure. The tectono-stratigraphy shows a transition from a late Mississippian regressive to an early Pennsylvanian transgressive and late Pennsylvanian transgressive–regressive sequences controlled by the basin-bounding transtensional faults. Detrital zircon U–Pb chronology displays a change of the provenance area from distant in the late Mississippian to more proximal in the Pennsylvanian. The magmatism indicates that the late Mississippian island-arc volcanic successions, related to subduction, progressively gave way to early Pennsylvanian magmatic activity indicative of regional asthenosphere upwelling, which suggests back-arc basins opened since ~ 319 Ma. The termination of the subduction is constrained by A-type granite plutons (~ 307 Ma). The Junggar terranes changed from an active back-arc basin behind an active subduction zone (319–307 Ma), to a post-subduction back-arc basin that continued to extend in 307–290 Ma. This back-arc basin extension is synchronous with voluminous Pennsylvanian–early Permian granite emplacement in both West Junggar and East Junggar blocks. Asthenospheric upwelling in the back-arc area was triggered by subduction, but continued after subduction had ceased. Transfer of juvenile magma to the crust was enhanced by crustal thinning, high thermal gradient, decompression melting and magma pathways along strike-slip faults. The prolonged back-arc setting provided a mechanism for rapid continental crust generation in the Paleozoic southwestern part of Central Asian Orogenic Belt. [ABSTRACT FROM AUTHOR]

Main conclusion: Fine mapping of wheat powdery mildew-resistance genePm4eto a 0.19 cM interval with sequence-based markers provides the foundation for map-based cloning and marker-assisted selection with breeder-friendly markers.Powdery mildew caused by Blumeria graminis f. sp. tritici is a wheat foliar disease that poses a serious threat to global wheat production. Pm4 is a resistance gene locus that has played a key role in controlling this disease in wheat production and a few resistance alleles of this locus have been identified. We have previously mapped the Pm4e allele to a 6.7 cM interval on chromosome 2AL. In this study, Pm4e was delimited to a 0.19 cM interval flanked by Xwgrc763 and Xwgrc865, through employment of a larger segregating population, derived from the cross of resistant parent D29 with susceptible parent Yangmai 158 (Y158), and enrichment of the genetic interval with markers developed on Chinese Spring (C.S.) survey sequence. In this interval, Pm4e co-segregated with a few markers, some of which were either D29-dominant or Y158-dominant, implying great sequence variation in the interval between D29 and Y158. Most of these co-segregation markers could not differentiate the Pm4 alleles from each other. Survey of 55 wheat cultivars with four co-dominant markers showed that the Pm4e-co-segregating loci always co-exist. Annotation of the Pm4e interval-corresponding C.S. sequence revealed more than a dozen resistance gene analogs clustered in a 2.4 Mb region, although C.S. is susceptible to the Pm4e-avirulent isolate Bgt2. This study has established the foundation for map-based cloning of Pm4e. Moreover, some of the co-dominant markers developed in this study could help in marker-assisted transfer of Pm4e into elite cultivars. [ABSTRACT FROM AUTHOR]

Sn-Ag-Cu based solder alloys are replacing Sn-Pb solders in electronic packaging structures of commercial electric devices. In order to evaluate the structural reliability, the mechanical property of solder material is critical to the numerical simulations. Annealing process has been found to stabilize material properties of Sn-37Pb solder material. In the current study, the annealing effect on tensile behaviour of Sn-3.0Ag-0.5Cu (SAC305) solder material is investigated and compared with Sn-37Pb solder. It is found that the tensile strength for both materials are more stabilized and consistent after the annealing process, nevertheless, the annealing process will improve the plasticity of SAC305 solder dominated by dislocation motion, and impede the occurrence of hardening deformation in Sn-37Pb solder dominated by grain-boundary sliding mechanism. Furthermore, the annealing effect is quantified in the proposed constitutive model based on unified creep-plasticity theory. The parameters are calibrated against the measured stress-strain relationships at the tensile strain rates ranging from 1 × 10−4 to 1 × 10−3 s−1. The numerical regressions for dominant parameters in the proposed model reveal the intrinsic differences between SAC305 and Sn-37Pb solders under annealing treatment. [ABSTRACT FROM AUTHOR]

The creep behaviour of Sn–3.0Ag–0.5Cu lead-free solder specimens with a diameter of 1.0 mm is investigated subjected to tensile forces from 10 to 25 N under electric currents ranging from 0 to 20 A. Due to the Joule heating effect, the solder temperature induced by electric current is measured to quantify the deterioration of tensile behaviour. Based on the observed steady-state creep deformation, the creep strain rate varies linearly with the tensile stress in the natural logarithmic coordinate with a stress threshold for the electric current between 0 and 10 A, and the natural logarithm of creep rate has a linear relationship with the square of current density. By revealing the dislocation climbing as the dominate creep mechanism under the coupled mechanical–electric–thermal loading, a modified Norton’s model is proposed which shows exponential dependence on the square of current density and the natural logarithm of tensile stress with the stress exponent enriched as a quadratic function of current density. [ABSTRACT FROM AUTHOR]

Powdery mildew, a wheat ( Triticum aestivum L.) foliar disease caused by Blumeria graminis (DC.) E.O. Speer f. sp. tritici, imposes a constant challenge on wheat production in areas with cool or maritime climates. This study was conducted to identify and transfer the resistance gene in the newly identified common wheat accession 'D29'. Genetic analysis of the F population derived from a cross of D29 with the susceptible elite cultivar Y158 suggested a single dominant gene is responsible for the powdery mildew resistance in this germplasm. This gene was mapped to chromosome 2AL in a region flanked by microsatellite markers Xgdm93 and Xhbg327, and co-segregated with sequence-tagged site (STS) markers Xsts_bcd1231 and TaAetPR5. An allelic test indicated that the D29 gene was allelic to the Pm4 locus. To further evaluate the resistance conferred by this gene and develop new germplasms for breeding, this gene, as well as Pm4a and Pm4b, was transferred to Y158 through backcross and marker-assisted selection. In the resistance spectrum analysis, the D29 gene displayed a resistance spectrum distinguishable from the other Pm4 alleles, including Pm4a, Pm4b, and Pm4c, and thus was designated as Pm4e. The identification of new allelic variation at the Pm4 locus is important for understanding the resistance gene evolution and for breeding wheat cultivars with powdery mildew resistance. [ABSTRACT FROM AUTHOR]

In rectilinear locomotion, snakes propel themselves by extending or contracting parts of the body. It is interesting that some large snakes will lift the activated part of the body during rectilinear motion. We hypothesize that snakes use this unique strategy named 'lifting behavior" to improve the performance of rectilinear motion on a rough horizontal surface. The purpose of this paper is to examine our hypothesis by examining whether rectilinear motion benefits from lifting behavior. In this study, we derive equations to estimate the energy consumption of rectilinear motion on a simplified 4-link snake robot model. We consider not only mechanical energy dissipation but also heat energy loss during motion. A criterion of minimum energy loss is used as a candidate for the strategy to show how much lifting behavior improves energy efficiency. Our analysis provides a framework for theoretical analysis of the energy cost of rectilinear locomotion for snakes, which can help biologists to further understand the behaviors of snakes. This study also provides some new insights into rectilinear locomotion. [ABSTRACT FROM AUTHOR]

This study analyzes the effects of listing changes within NASDAQ market segments during the period of 1998 to 2005. We find that firms phased up from the NASDAQ Small Capital Market (SmallCap) to the NASDAQ National Market (NNM) experienced significant declines in bid-ask spreads, the volatility of returns, and the probability of informed trading, and firms that phased down from NNM to the SmallCap experienced decreases in bid-ask spreads, but insignificant changes in the volatility of returns and the probability of informed trading. We also estimate simultaneous equations models of bid-ask spreads, return volatility, and trading volume for both groups of firms. The results confirm that improved liquidity is associated with the listing changes for the phase-up firms. However, the simultaneous equations model suggests that the decreases in bid-ask spreads for the phase-down firms are caused by the changes in share prices. [ABSTRACT FROM AUTHOR]

We study the extent to which social ties between people can be inferred in large social network, in particular via active user interactions. In most online social networks, relationships are lack of meaning labels (e.g., 'colleague' and 'intimate friends') due to various reasons. Understanding the formation of different types of social relationships can provide us insights into the micro-level dynamics of the social network. In this work, we precisely define the problem of inferring social ties and propose a Partially-Labeled Pairwise Factor Graph Model (PLP-FGM) for learning to infer the type of social relationships. The model formalizes the problem of inferring social ties into a flexible semi-supervised framework. We test the model on three different genres of data sets and demonstrate its effectiveness. We further study how to leverage user interactions to help improve the inferring accuracy. Two active learning algorithms are proposed to actively select relationships to query users for their labels. Experimental results show that with only a few user corrections, the accuracy of inferring social ties can be significantly improved. Finally, to scale the model to handle real large networks, a distributed learning algorithm has been developed. [ABSTRACT FROM AUTHOR]

Unfortunately, the style of the units was incorrectly published (“cm” instead of “cM”) throughout the original article. [ABSTRACT FROM AUTHOR]