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The shear transformation zone (STZ) and ductility of Zr-based bulk metallic glass with varying hydrogen content were analyzed using serrated flow in nanoindentation, with each serration representing the formation and expansion of one or more shear bands. An exponential model was employed to extract the serrations and obtain a certain range of shear stress, and STZ size was estimated via thorough statistical data analysis. The experimental results demonstrated a striking decrease in the serration number and width of the load-displacement curve after hydrogenation, which is similar to the effects of the nanoindentation loading rate. The calculated STZ volume and atomic number were in good agreement with those reported in the literature. The STZ volume, size, activation energy, and activation volume also increased with the increased hydrogen content, leading to shear band formation and proliferation as well as increased shear band density, plastic zone, and plasticity. At the microscopic level, the hydrogen addition accelerated free volume formation and enhanced flow ability between the atoms, as characterized by the improvement of plasticity. At the macroscopic level, hydrogen addition promoted shear band nucleation and multiplication and increased shear band density, plastic zones, and plasticity. The metallic glass plasticity was greatly improved after hydrogenation as assessed via compression tests at room temperature, confirming the rationale of the experimental results.

Al2O3 ceramics were successfully brazed under high vacuum conditions using the active Ni50Ti50 master alloy at 1320 °C with different holding time. The interfacial microstructure of the joint was characterized using SEM, EDS and TEM. The effects of holding time on the microstructure evolution and mechanical properties of the joints were investigated. The results revealed that the typical structure of the Al2O3/Ni–Ti joint brazed at 1320 °C for 45 min was Al2O3/AlNi2Ti + Ni2Ti4O/Ni2Ti4O/TiNi. Ni2Ti4O was continuously distributed as a layer adjacent to the Al2O3 substrate, whereas columnar AlNi2Ti phase existed in the Ni2Ti4O layer near the Al2O3 side. With the prolongation of holding time, the thickness of Ni2Ti4O layer increased obviously, and AlNi2Ti became longer and coarser. The maximum shear strength of 109 MPa was obtained when the joint was brazed at 1320 °C for 45 min. The hardness, Young's modulus and elastic recovery of the phases across the joints became a gradient property. The interfacial reaction layer with appropriate thickness was found beneficial for enhancing the Al2O3/Ni–Ti/Al2O3 joint strength.

We utilized the pair distribution function method to characterize the pressure-induced polyamorphic transition in Ce60Al20Cu20 and Ce55Al45 metallic glass at room temperature. Using synchrotron high-energy x-ray diffraction we collected scattering information from a large Q-space coverage, which in turn gave a high resolution g(r) that provided accurate local structure information. We observed a sudden change in compressibility and the nearest neighbor distance at 3.50–6.32 GPa for Ce60Al20Cu20 and 2.20–6.89 GPa for Ce55Al45. The origin of the volume collapse seemed to be pressure-induced qualitative changes in bond shortening that corresponded to different coordination spheres. The polyamorphic transitions in these two systems from low-density glass (LDG) to high-density glass (HDG) are associated with local atomic rearrangements.

In situ high-energy X-ray diffraction of Nd60Fe30Al10 and Ce70Al10Cu20 metallic glasses is carried out under high pressure. During compression, Ce70Al10Cu20 and Nd60Fe30Al10 exhibit a polyamorphic transition from low-density state below 2.0 and 10.0 GPa, to high-density state above 8.4 and 21.1 GPa, respectively. The intermediate hysteresis regions are the mixture of both phases. Electrical resistance measurements under high pressure show that Ce70Al10Cu20 display a discontinuous change in pressure dependence curve of resistivity at around 1.7 GPa. The addition of Fe atom gives a significant standoff of phase transition pressure in Nd60Fe30Al10. The results in this work suggest that the solute element and microstructure of lanthanide solvent aggregates have implications on the polyamorphic transition in metallic glasses.

After the electric vehicle battery swapping station (BSS) is connected to microgrid, the battery in the BSS can provide auxiliary services through the battery to grid(B2G) technology. It is not only able to reduce the configuration capacity of the energy storage system and the construction cost of the microgrid, but also can improve the operating profit of BSS. In this context, this paper proposes a method for full battery to participate in B2G service. Secondly, we propose a coordinated charging strategy for BSS in the microgrid with the goal of minimum daily charging cost. Finally, an example is given to analyze the effectiveness of the proposed B2G method and the coordinated charging strategy.

A new Al-based composite consisting of submicron-sized α-Al matrix embedded with precipitated intermetallic phases was developed by controlling the devitrification process of an Al–Ni–Y–Co–La amorphous alloy. Such a homogeneous composite structure presented an ultrahigh strength of about 1.34 GPa and a large compressive plastic strain up to 22%. The unique mechanical properties during compression are mainly attributed to the dislocation slip deformation of ductile α-Al matrix and the shear-induced refinement of strengthening intermetallic phases.

Distribution network is the connection of the generate system and transmission line, which is at the last stage of the process of the energy transportation. It is complex to judge the direction of the power flow, so that it is significant to study a more effective method to judge the direction of the power flow in the Overhead power line. This paper introduces the principle of the Biot-Savart Law firstly and then introduces the necessity of power system simulation,. To complete the analysis and calculation of electromagnetic field around Overhead power line when Signals Phase Earth Fault occur in the power system, the spatial rectangular coordinate system was established based on the arrangement of the Overhead power line. After the study of 10KV distribution network we create fault simulation platform ATPDraw and based on MATLAB simulation software, we use the electromagnetic transient program graphical input function and the strong calculation function of MATLAB to calculate electromagnetic field around Overhead power line, so as to provide the basis for further analysis. − × π and the direction is perpendicular to the surface determined by the current element and vector r,curve the finger and the direction of thumb is the direction of dB.That is Idl ,dB and r accord the right-hand screw rule. The law of Biot Savart is proved by the H.C. Oster experiment. The experiment illustrate that the force which is given by long straight current-carrying to the magnetic pole is horizontal force. J.B. Biot and F.Savart believe that the force that current element gives to magnetic pole is perpendicular to the surface determined by current element and the magnetic pole, in a same way, a horizontal force. They make a conclusion about the relationship between the force and the angle of the bucking current-carrying,as well as the relationship with distance via the experiment that measure the force given by straight and curve current-carrying to the magnetic sole. With the help of P.S.M. Laplace, they got the rule of the effect of the current element to the magnetic pole. According to the view of the close range function ,the conclusion is understand by public as a rule of the production of magnetic field .

Although aerobic glycolysis (the Warburg effect) is a hallmark of cancer, key questions, including when, how, and why cancer cells become highly glycolytic, remain less clear. For a largely unknown regulatory mechanism, a rate-limiting glycolytic enzyme pyruvate kinase M2 (PKM2) isoform is exclusively expressed in embryonic, proliferating, and tumor cells, and plays an essential role in tumor metabolism and growth. Because the receptor tyrosine kinase/PI3K/AKT/mammalian target of rapamycin (RTK/PI3K/AKT/mTOR) signaling cascade is a frequently altered pathway in cancer, we explored its potential role in cancer metabolism. We identified mTOR as a central activator of the Warburg effect by inducing PKM2 and other glycolytic enzymes under normoxic conditions. PKM2 level was augmented in mouse kidney tumors due to deficiency of tuberous sclerosis complex 2 and consequent mTOR activation, and was reduced in human cancer cells by mTOR suppression. mTOR up-regulation of PKM2 expression was through hypoxia-inducible factor 1α (HIF1α)-mediated transcription activation, and c-Myc–heterogeneous nuclear ribonucleoproteins (hnRNPs)-dependent regulation of PKM2 gene splicing. Disruption of PKM2 suppressed oncogenic mTOR-mediated tumorigenesis. Unlike normal cells, mTOR hyperactive cells were more sensitive to inhibition of mTOR or glycolysis. Dual suppression of mTOR and glycolysis synergistically blunted the proliferation and tumor development of mTOR hyperactive cells. Even though aerobic glycolysis is not required for breach of senescence for immortalization and transformation, the frequently deregulated mTOR signaling during multistep oncogenic processes could contribute to the development of the Warburg effect in many cancers. Components of the mTOR/HIF1α/Myc–hnRNPs/PKM2 glycolysis signaling network could be targeted for the treatment of cancer caused by an aberrant RTK/PI3K/AKT/mTOR signaling pathway.

The effect of chamber gas pressure on the amorphicity of Al85Ni5Y10 alloy was studied for the melt-spinning process. The amorphicity of as-quenched ribbons was characterized by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The chamber atmosphere pressure is crucial to the cooling rate of melt spinning. At high vacuum, at pressure less than 0.001 atm, fully crystalline fragments are obtained. Monolithic amorphous ribbons were only obtained at a gas pressure of 0.1 atm, 0.2 atm or higher. The extended contact length between ribbons and the copper wheel contributes to the high cooling rate of melt spinning in Al-based glass forming alloys; that is supported by images recorded by a high-speed camera. Higher chamber pressure increases contact length between ribbons and the wheel, which is qualitatively elucidated by Bernoulli's equation. Accepted version