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The effects of hot-rolling (HR), cold-rolling (CR), and HR + CR followed by aging on the microstructure and mechanical properties of the medium-entropy alloy (MEA) Ni43.4Co25.3Cr25.3Al3Ti3were investigated. The geometrically-necessary dislocation (GND) density increased with increasing cold rolling reduction to 1.8–2.4 × 1014m−2, which is eight times the 2.9 × 1013m−2found in the as-hot-rolled MEA. Higher dislocation density before aging led to a finer, higher volume fraction of L12nanoparticles as well as finer grains, which resulted from both accelerated nucleation on dislocations and, possibly, accelerated pipe diffusion via the dislocations. The aged CR MEA exhibited an excellent strength-ductility combination (yield strength ~ 1414 MPa, ultimate tensile strength ~ 1605 MPa, elongation ~ 15%) with precipitate strengthening accounting for 26% of the yield strength, which was better than the mechanical properties of the aged HR MEA (yield strength ~ 897 MPa, ultimate tensile strength ~ 1217 MPa, elongation ~ 32.3%). A combination of hot-rolling and cold-rolling also leads to a good strength-ductility combination (yield strength ~ 1501 MPa, ultimate tensile strength ~ 1651 MPa, elongation ~ 20.8%), with grain boundary strengthening and precipitate strengthening accounting for 62% and 25% of the yield strength, respectively. Substantial partitioning and fluctuations of the principle atoms were observed in as-CR sample due to dislocations interacting with the alloying atoms, i.e. several nano-scaled regions were enriched in Ni, Al, and Ti, and depleted in Cr and Co. In addition, Al and Ti have more substantial local fluctuations in composition than Ni, Co, and Co.

• A novel Al-La-Mg-Mn alloy was designed for selective laser melting. • The formation of hierarchical intermetallic was investigated. • The SLM-printed Al-La-Mg-Mn alloy exhibits an excellent tensile strength and appreciable failure strain. • The effect of hierarchical intermetallic on ductility was investigated. Developing high-strength Al-(La, Ce) alloys for additive manufacturing (AM) would entail considerable economic benefits. In this work, a novel near-eutectic Al-La alloy containing 5.50 wt.% Mg and 0.60 wt.% Mn was designed and fabricated via selective laser melting (SLM). Submicron Al 11 La 3 intermetallics with 3D continuous cellular-dendritic and granular morphologies were observed at the interior and boundary of the melt pool, respectively. Interestingly, these intermetallics are hierarchical and contained numerous Al 6 Mn and Mg 2 Si secondary nanoprecipitates. The as-fabricated alloy exhibited a tensile yield strength (YS) of 334 MPa and ultimate tensile strength (UTS) of 588 MPa at room temperature, which is the highest UTS reported for Al-(La, Ce) alloys with an appreciable failure strain of ∼6.4%. The 3D continuous cellular dendritic intermetallic and high Mg content afford significant strengthening and work hardening ability. In addition, the hierarchical feature of the intermetallics generated additional microcracks to coordinate the deformation. [ABSTRACT FROM AUTHOR]

This article develops an efficient fault diagnostic scheme for battery packs using a novel sensor topology and signal processing procedure. Cross-cell voltages are measured to capture electrical abnormalities, and recursive correlation coefficients between adjacent voltages are calculated to embody system state. Then discrete wavelet packet transform is applied on the correlation sequences to extract diverse characteristic indexes, wherein the most representative components are refined as fault features by principal component analysis. Afterward, resorting to multiclass relevance vector machine, sparse classification models are constructed to cognize fault patterns, and accordingly, fault types and grades are evaluated. Common faults, including external and internal short-circuit, thermal abuse, and loose connection, are physically triggered on a series pack to acquire realistic data set. Experimental verifications under different conditions and algorithmic configurations suggest that the proposed diagnosis scheme can give accurate and reliable assessments on different fault specifics, with a fault isolation success rate of 84% and a fault severity grading success rate of 90%.

A large gas reservoir in the Sinian Dengying Fm was recently discovered in Anyue area, central Sichuan Basin. In order to promote the oil and gas exploration in this area, it is of great significance to sustainably deepen the analysis on its high-quality reservoir distribution and source-reservoir assemblage. In this paper, a series of studies were performed on the sequence frameworks and sedimentary filling evolution characteristics of the Dengying Fm in central–western Sichuan Basin, and their controlling effects on the reservoir development and distribution and source-reservoir assemblage during its sedimentation. It is shown that the Deyang–Anyue paleo-rift is, on the whole, distributed in a NW direction, and is morphologically wide and steep in the north, but narrow and gentle in the south. There are two rift boundaries of the second and fourth members of Dengying Fm (Deng 2 Member and Deng 4 Member, respectively). The rift of Deng 2 Member is distributed in the shape of “U” in Deyang–Neijiang area. Dengying Fm is divided into four third-order sequences (SQ1–SQ4). In SQ3 of Gaoshiti–Moxi area, central Sichuan Basin, a complete sedimentation reflection structure of transgressive overlap and regressive progradation can be identified with early–middle Deng 4 Member platform margin. The paleo-rift was in embryo before the sedimentation of Sinian, so the sedimentary filling and lithofacies distribution of the Sinian were influenced by the inherited activities of pre-Sinian rifts. The favorable distribution zones of high-quality reservoirs are located at the rift margins of Deng 2 and Deng 4 Members that were formed respectively during the SQ2 and SQ4 and the platform margin of early Deng 4 Member that was formed during the SQ3. A laterally connected source-reservoir assemblage occurs at the margins of Deng 2 and Deng 4 Members around the Lower Cambrian source rocks of the paleo-rift. The northwestward extending margin zone along the eastern flank of the paleo-rift shows a good potential for hydrocarbon accumulation.

A butt-coupled low dispersion slow light photonic crystal waveguide has been proposed in this paper. It is comprised of two types of photonic crystal waveguides which have opposite dispersion curve. These two types of photonic crystal waveguides have been solely adjusted the radius of air-holes rather than change its position. Based upon our analysis, the average group index achieves 35 with =6nm and this scope can be enlarged by fine adjustment. Finite-different timedomain method has been adopted to execute the simulation and the result demonstrates that the pulse has been modified when it propagates in this butt-coupled photonic crystal waveguide.

Since the Anyue Gasfield, located in the central Sichuan paleo-uplift of the Sichuan Basin, was discovered, great efforts have been made to work on natural gas exploration and discovery in the Sinian–Lower Paleozoic in the north slope of present paleo-uplift which has similar depositional settings. It is verified by the breakthrough of natural gas exploration in the second Member of Upper Sinian Dengying Formation in the north slope of central Sichuan paleo-uplift by wildcat well PT1 and the new sign of natural gas exploration in the Canglangpu Formation of Lower Cambrian and the fourth Member of Dengying Formation by Well JT1 that there are also favorable conditions for the formation of large-scale gas province in the north slope. In order to determine the natural gas exploration potential of Sinian–Lower Paleozoic in the central Sichuan paleo-uplift and provide the guidance for the following exploration deployment, this paper analyzed the petroleum geological conditions of Sinian–Lower Paleozoic in the north slope. And the following research results were obtained. First, the marginal platform belts in the second and the fourth Member of Sinian Dengying Formation in the north slope are basically separated areally, and they are superior to the Gaoshiti–Moxi area in terms of marginal platform width and sedimentary thickness and are intrinsically advantageous in sedimentation. Second, compared with the Gaoshiti–Moxi area, the reservoirs of Sinian Dengying Formation in the north slope are better in reservoir conditions, and many sets of quality reservoirs are developed vertically in Sinian–Cambrian. Third, hydrocarbon accumulation elements of Sinian Dengying Formation are better allocated in the north slope. Lithological traps are developed with a larger cumulative area. Wells JT1 and PT1 verify that there is gas in the lithological trap of the fourth and the second Member of Dengying Formation and large-scale lithological gas reservoirs are developed in the slope setting. In conclusion, compared with the Gaoshiti–Moxi area, the Sinian–Lower Paleozoic in the north slope is superior in petroleum geological conditions and has the advantage of multi-layer stereoscopic exploration vertically, presenting a great natural gas exploration potential and promising exploration prospects, so it is a new important strategic zone of conventional natural gas exploration in the Sichuan Basin.

In this paper, a simple method of phase correction by using a micromachined deformable mirror (MMDM) is demonstrated. With correction of high-order phases due to propagating through medium, we obtained a clean pulse shape, flattened spectral phase and decreased the femtosecond laser pulse duration. It is shown by our experiment that the deformable mirror is an effective and easy method for adaptive phase correction.