Topological transition metal dichalcogenides (TMDCs) have attracted much attention due to their potential applications in spintronics and quantum computations. In this work, the structural and ...electronic properties of topological TMDCs candidate ZrTe
are systematically investigated under high pressure. A pressure-induced Lifshitz transition is evidenced by the change of charge carrier type as well as the Fermi surface. Superconductivity is observed at around 8.3 GPa without structural phase transition. A typical dome-shape phase diagram is obtained with the maximum T
of 5.6 K for ZrTe
. Furthermore, the theoretical calculations suggest the presence of multiple pressure-induced topological quantum phase transitions, which coexists with emergence of superconductivity. The results demonstrate that ZrTe
with nontrivial topology of electronic states displays new ground states upon compression.
Nanosized CeNbNiO catalysts have been prepared by a modified sol-gel method and investigated in the oxidative dehydrogenation of propane to propene (ODHP). The addition of Nb into NiO can enhance the ...propene selectivity, while Ce introduction can largely increase propane conversion at low temperature. With 1.5Ce3NbNiO catalyst, a propene yield of 10.4% was obtained at 250 °C. XRD, N₂-adsorption, H₂-TPR, XPS, O₂-TPD, NH₃-TPD and pulse reaction have been performed to study the intrinsic difference between these NiO-based catalysts. A strong interaction between Ni and Ce/Nb species was clearly evidenced for the doped NiO samples. The doped elements affected greatly the catalyst properties such as surface acidity and the reactivity of oxygen species, which are closely related to the catalytic performance of the catalysts. Graphical Abstract Nanosized CeNbNiO catalysts have been prepared by a modified sol-gel method and investigated in the oxidative dehydrogenation of propane to propene. With 1.5Ce3NbNiO catalyst, a propene yield of 10.4% was obtained at 250 °C. The effects of doped elements (Ce, Nb) on the catalytic performance have been discussed. graphic removed
The correlation between meteorological parameters and intracerebral hemorrhage (ICH) occurrence is controversial. Our research explored the effect of daily meteorological parameters on ICH risk in a ...subtropical monsoon basin climate.
We retrospectively analyzed patients with ICH in a teaching hospital. Daily meteorological parameters including temperature (TEM), atmospheric pressure (PRE), relative humidity (RHU), and sunshine duration (SSD) were collected, with the diurnal variation (daily maximum minus minimum) and day-to-day variation (average of the day minus the previous day) calculated to represent their fluctuation. We adopted a time-stratified case-crossover approach and selected conditional logistic regression to explore the effect of meteorological parameters on ICH risk. The influence of monthly mean temperature proceeded via stratified analysis. Air pollutants were gathered as covariates.
Our study included 1052 eligible cases with ICH. In a single-factor model, the risk of ICH decreased by 5.9% (
<0.001) for each 1°C higher of the daily mean TEM, and the risk increased by 2.4% (
=0.002) for each 1hPa higher of the daily mean PRE. Prolongation of daily SSD inhibited the risk of ICH, and OR was 0.959 (
=0.007). The risk was raised by 7.5% (
=0.0496) with a 1°C increment of day-to-day variation of TEM. In a two-factor model, the effect of daily mean TEM or daily SSD on ICH risk was still statistically significant after adjusting another factor. The influence of meteorological parameters on ICH risk continued in cold months but disappeared in warm months after stratified analysis.
This research indicates daily TEM and SSD had an inverse correlation to ICH risk in a subtropical monsoon basin climate. They were independent when adjusted by another factor. Daily PRE and day-to-day TEM variation were positively related to ICH risk. The correlation of daily meteorological factors on ICH risk was affected by the monthly thermal background.
Abstract
Controllable interfacial strain can manipulate the physical properties of epitaxial films and help understand the physical nature of the correlation between the properties and the atomic ...microstructures. By using a proper design of vicinal single-crystal substrate, the interface strain in epitaxial thin films can be well controlled by adjusting the miscut angle via a surface-step-terrace matching growth mode. Here, we demonstrate that LaAlO
3
(LAO) substrates with various miscut angles of 1.0°, 2.75°, and 5.0° were used to tune the dielectric properties of epitaxial CaCu
3
Ti
4
O
12
(CCTO) thin films. A model of coexistent compressive and tensile strained domains is proposed to understand the epitaxial nature. Our findings on the self-tuning of the compressive and tensile strained domain ratio along the interface depending on the miscut angle and the stress relaxation mechanism under this growth mode will open a new avenue to achieve CCTO films with high dielectric constant and low dielectric loss, which is critical for the design and integration of advanced heterostructures for high performance capacitance device applications.
Portal vein ligation (PVL) induces atrophy/hypertrophy complex (AHC). We hypothesised that simultaneous bile duct and portal vein ligation (BPL) might induce proper bile acid (BA) retention to ...enhance AHC by activating BA-mediated FXR signalling in the intact liver and promoting apoptosis in the ligated liver. We established rat models of 90% BPL and 90% PVL and found that BPL was well-tolerated and significantly accelerated AHC. The enhanced BA retention in the intact liver promoted hepatocyte proliferation by promoting the activation of FXR signalling, while that in the ligated liver intensified caspase3-mediated apoptosis. Decreasing the BA pools in the rats that underwent BPL could compromise these effects, whereas increasing the bile acid pools of rats that underwent PVL could induce similar effects. Second-stage resection of posterior-caudate-lobe-spearing hepatectomy was performed 5 days after BPL (B-Hx), PVL (V-Hx) or sham (S-SHx), as well as whole-caudate-lobe-spearing hepatectomy 5 days after sham (S-Hx). The B-Hx group had the most favourable survival rate (93.3%, the S-SHx group 0%, the S-Hx group 26.7%, the V-Hx group 56.7%, P < 0.01) and the most sustained regeneration. We conclude that BPL is a safe and effective method, and the acceleration of AHC was bile acid-dependent.
To study the integral forming process of torsion damper shell pulley with characteristic structure is of great significance for producing and developing of the rotational part such as shell pulley. A ...processing way was proposed by combining plate bending forming and roller structure design, to integral forming torsion damper shell pulley. A model for two-step bending forming was establishedvia finite element method. Under the radial feeding of roller, the outer edge of plate was subjected to compress thickening and secondary thickened after bending, and effective stress and metal flow in the deformation zone were analyzed by using marking point. Combining with the structural characteristics of shell pulley, a design criterion "rotating thickening, gathering thickening" of roller was proposed. The metal flow in deformation zone was effectively controlled through the characteristic structure of roller, thereby the specific region to forming multi-wedge toothwas obtained. The quantitative analysis of the instantaneous part section in the forming process, combining with the design criteria of roller structure and material flow rate, radius and arc angle of roller were determined. With the objective forming parameters, the comparison between the simulation results and the experimental are basically coincided, the ribs were fully formed and the specific regions was thickened to minimum value, which verified the feasibility of sheet-bulk metal rotary bending forming theory and the design criterion of roller structure.
针对具有特征结构的扭转减振器壳体带轮的整体成形工艺研究，对壳体带轮这类回转体零件的生产与开发具有重要意义。提出一种结合板材旋弯成形工艺和旋轮结构设计，整体成形扭转减振器壳体带轮。通过有限元模拟，建立两道次旋弯成形模型，旋轮沿径向进给过程中，使板坯外缘发生压缩增厚和弯曲聚料后的二次增厚，并采用标记点法分析变形区等效应力和材料流动。结合壳体带轮结构特点，提出一种"旋弯增厚、聚料增厚"旋轮结构设计准则，通过旋轮特征结构有效控制变形区金属流动，由此获得用于成形多楔齿的特定区域。对成形过程中零件瞬时截面的定量分析，结合旋轮结构设计准则和材料流动速率，确定旋轮弧面半径和圆心角。在目标成形工艺参数下，有限元数值模拟和试验结果基本一致，凸筋成形饱满，特征区域增厚到最小厚度值，验证了金属板材旋弯成形理论和旋轮结构设计准则的可行性。
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