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Artificial vision is crucial for most artificial intelligence applications. Conventional artificial visual systems have been facing challenges in terms of real-time information processing due to the physical separation of sensors, memories, and processors, which results in the production of a large amount of redundant data as well as the data conversion and transfer between these three components consuming most of the time and energy. Emergent optoelectronic memristors with the ability to realize integrated sensing-computing-memory (ISCM) are key candidates for solving such challenges and therefore attract increasing attention. At present, the memristive ISCM devices can only perform primary-level computing with external light signals due to the fact that only monotonic increase of memconductance upon light irradiation is achieved in most of these devices. Here, we propose an all-optically controlled memristive ISCM device based on a simple structure of Au/ZnO/Pt with the ZnO thin film sputtered at pure Ar atmosphere. This device can perform advanced computing tasks such as nonvolatile neuromorphic computing and complete Boolean logic functions only by light irradiation, owing to its ability to reversibly tune the memconductance with light. Moreover, the device shows excellent operation stability ascribed to a purely electronic memconductance tuning mechanism. Hence, this study is an important step towards the next generation of artificial visual systems.

• Although the nano-dispersed precipitation of G-phase within the grain hardens the alloy remarkably, its large amount of precipitation at the grain boundary leads to serious alloy embrittlement. • For the first time, the crystal structure transition of nano-dispersed precipitates from the Fe 2 TiSi-L2 1 to the Ni 16 Ti 6 Si 7 -G phase is observed within the ferrite at the early stage of aging. • Guided by current TEM and DFT results, the interfacial energy is predicted to play a leading role in forming the cube-on-cube orientation relationship between α-Fe and G-phase. • Adopting the "cold-rolling and aging" process to effectively avoid its precipitation at grain boundaries, a class of high-performance ferroalloys with both high strength and good ductility is realized. A typical G-phase strengthened ferritic model alloy (1Ti:Fe-20Cr-3Ni-1Ti-3Si, wt.%) has been carefully studied using both advanced experimental (EBSD, TEM and APT) and theoretical (DFT) techniques. During the classic "solid solution and aging" process, the superfine (Fe, Ni) 2 TiSi-L2 1 particles densely precipitate within the ferritic grain and subsequently transform into the (Ni, Fe) 16 Ti 6 Si 7 -G phase. In the meanwhile, the elemental segregation at grain boundaries and the resulting precipitation of a large amount of the (Ni, Fe) 16 Ti 6 Si 7 -G phase are also observed. These nanoscale microstructural evolutions result in a remarkable increase in hardness (100–300 HV) and severe embrittlement. When the "cold rolling and aging" process is used, the brittle fracture is effectively suppressed without loss of nano-precipitation strengthening effect. Superhigh yield strength of 1700 MPa with 4% elongation at break is achieved. This key improvement in mechanical properties is mainly attributed to the pre-cold rolling process which effectively avoids the dense precipitation of the G-phase at the grain boundary. These findings could shed light on the further exploration of the precipitation site via optimal processing strategies. [Display omitted] [ABSTRACT FROM AUTHOR]

Inversion domains (IDs) are common defects in N-polar III-nitride thin films grown on sapphire substrates. In this work, the atomic structure and lateral migration of the randomly distributed Al-polar nanoscale IDs in N-polar AlN films subjected to high-temperature thermal annealing are investigated. With the increasing annealing temperature and time, Al-polar AlN IDs gradually shrunk in sizes. The vertical stripes transformed into cone-shaped caps on top of the AlN columns and were completely removed at last. The annihilation of the IDs was explained in terms of the lateral migration of the inversion domain boundary (IDB) induced by the imbalance of the strain state on two sides of the IDB. This work clarifies the evolution mechanism of AlN IDs during high-temperature annealing, providing a promising approach in the realization of uniform-polar AlN template for the development of high-efficiency optoelectronic and electronic devices.

The microstructure of twinning as well as the phase boundary between 1:5H and 2:17R phase in Fe-rich Sm2Co17-type magnets was characterized at atomic scale using nanobeam diffraction and high-resolution STEM-HAADF imaging, and the reason for the dramatic increase of coercivity during slow cooling was investigated based on the microchemistry analysis. The twinning relationship in the 2:17R phase originates from ordered substitution of Sm atoms by Co–Co atomic pairs on every three (3¯033) and (303¯3) planes, leading to formation of two corresponding equivalent twin variants. The basal plane of the 2:17R phase, the 1:3R platelet phase across the 2:17R cell and the 1:5H cell boundary phase between two adjacent 2:17R cells all can act as effective twin boundary. The cell boundary phase is precipitated along the pyramidal habit plane, and a fully coherent phase boundary (PB) is formed between the 1:5H and 2:17R phases with the orientation relationship to be PB//(112¯1)1:5H//(101¯1)2:17R. The phase boundary may either be parallel to or intersect with the pyramidal planes occupied by Co–Co atomic pairs. The substantial increase of coercivity during slow cooling is ascribed to the development of large gradient of the elements concentration within the cell boundary phase, resulting in large gradient of domain wall energy, and thus the pinning strength of the cell boundary phase against magnetic domain wall motion is significantly enhanced.

The real time analysis structure evolution of BNNT with compression showed that the formation of V-shape in the post-buckling before BNNT fracture was reversible.

For the accuracy of experimental results, preparing a high quality polished surface and cross-section of the materials for further analysis using electron back-scattered diffraction (EBSD), electron probe microanalysis (EPMA), and scanning probe microscopy (SPM) is extremely important. Broad ion beam (BIB) polishing, a method based on the principle of ion bombardment, has irreplaceable advantages. It makes up for the drawbacks and limitations of traditional polishing methods such as mechanical polishing, electrochemical polishing, and chemical polishing. The ions will not leave the bombardment area during polishing, which makes the BIB method suitable for porous materials. The energy of the ion beam can be adjusted according to the sample to reduce the deformation and strain of the polishing area, especially for fragile, soft, and hard materials. The conditions that need to be controlled during BIB polishing are simple. This paper demonstrated the unique advantages of BIB polishing technology in porous, layered and powder materials characterization through some typical application examples, and guided more researchers to understand and utilize BIB polishing technology in the development of new applications.

A novel Cu-SnO2anode material derived from Cu6Sn5alloy, retaining high conductivity of Cu and high theoretical capacity of SnO2with a facile synthesizing process by oxidation and reduction method. The novel Cu structure penetrates in the composite particles inducing high conductivity and space-confined SnO2, which restrict the pulverization of SnO2during lithiation/delithiation process.

The thermal warpage of nitrogen-doped Czochralski (NCZ) silicon wafers affected by preannealing was investigated. After preannealing at 1000 °C for 6 h, the warpage of the NCZ silicon wafers was suppressed during subsequently thermal warping tests, while the silicon wafers grown under an argon ambient (ACZ) showed an increase in warpage. Nitrogen was considered to be very effective to increase the mechanical strength of silicon wafers because of the formation of nitrogen–oxygen clusters with smaller sizes. After preannealing at 1000 °C for 16 h, both ACZ and NCZ silicon wafers showed a large increase of warpage due to the large amount of oxygen precipitation.

Aluminum is a typical metal with a quick and self-healing passivation course. The dense oxidation film effectively prevents aluminum from being continuously oxidized by oxygen or water vapor. In this study, we report a kind of aluminum alloy powders that shows popcorn-like shape transformation in the reaction with low-temperature water vapor, which demonstrates that circumventing the passivation of aluminum alloy through the self-sustaining shape changes in hydrolysis reaction can become a reality. In-situ experiments disclosed that the hydrogen-assisted cracking and the interfacial corrosion play important roles in facilitating aluminum reactivity and cause a popcorn-like shape transformation. Moreover, the amorphous hydrated layer may enhance water transportation through the oxidation layer by the ‘spongy’ behavior. This study reveals a special corrosion mechanism of aluminum and provides a promising perspective of using aluminum in the energy field.