다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Metal Oxides and Oxysalts as Anode Materials for Li Ion Batteries

A promising family of mixed transition-metal oxides (MTMOs) (designated as Ax B3-x O4 ; A, B=Co, Ni, Zn, Mn, Fe, etc.) with stoichiometric or even non-stoichiometric compositions, typically in a spinel structure, has recently attracted increasing research interest worldwide. Benefiting from their remarkable electrochemical properties, these MTMOs will play significant roles for low-cost and environmentally friendly energy storage/conversion technologies. In this Review, we summarize recent research advances in the rational design and efficient synthesis of MTMOs with controlled shapes, sizes, compositions, and micro-/nanostructures, along with their applications as electrode materials for lithium-ion batteries and electrochemical capacitors, and efficient electrocatalysts for the oxygen reduction reaction in metal-air batteries and fuel cells. Some future trends and prospects to further develop advanced MTMOs for next-generation electrochemical energy storage/conversion systems are also presented.

Mixed transition-metal oxides: design, synthesis, and energy-related applications.

The room-temperature manipulation of magnetization by an electric field using the multiferroic BiFeO3 represents an essential step towards the magnetoelectric control of spintronics devices.

Multiferroics: Towards a magnetoelectric memory

Structural symmetry-breaking plays a crucial role in determining the electronic band structures of two-dimensional materials. Tremendous efforts have been devoted to breaking the in-plane symmetry of graphene with electric fields on AB-stacked bilayers or stacked van der Waals heterostructures. In contrast, transition metal dichalcogenide monolayers are semiconductors with intrinsic in-plane asymmetry, leading to direct electronic bandgaps, distinctive optical properties and great potential in optoelectronics. Apart from their in-plane inversion asymmetry, an additional degree of freedom allowing spin manipulation can be induced by breaking the out-of-plane mirror symmetry with external electric fields or, as theoretically proposed, with an asymmetric out-of-plane structural configuration. Here, we report a synthetic strategy to grow Janus monolayers of transition metal dichalcogenides breaking the out-of-plane structural symmetry. In particular, based on a MoS2 monolayer, we fully replace the top-layer S with Se atoms. We confirm the Janus structure of MoSSe directly by means of scanning transmission electron microscopy and energy-dependent X-ray photoelectron spectroscopy, and prove the existence of vertical dipoles by second harmonic generation and piezoresponse force microscopy measurements.

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Janus monolayers of transition metal dichalcogenides

Influence of Li-dopants on the luminescent and ferroelectric properties of ZnO thin films

In this paper, acoustic emission (AE) and digital image correlation methods were applied to monitor interface cracking in thermal barrier coatings under compression. The interface failure process can be identified via its AE features, including buckling, delamination incubation and spallation. According to the Fourier transformation of AE signals, there are four different failure modes: surface vertical cracks, opening and sliding interface cracks, and substrate deformation. The characteristic frequency of AE signals from surface vertical cracks is 0.21 MHz, whilst that of the two types of interface cracks are 0.43 and 0.29 MHz, respectively. The energy released of the two types of interface cracks are 0.43 and 0.29 MHz, respectively. Based on the energy released from cracking and the AE signals, a relationship is established between the interface crack length and AE parameters, which is in good agreement with experimental results.

Acoustic emission assessment of interface cracking in thermal barrier coatings

Thermal damage of SiC particulate-reinforced aluminum composites (MMCs) caused by laser thermal shock was investigated. The damage was induced by a combination of laser beam thermal shock and mechanical loads. The MMCs have two kinds of particle distributions, one is uniform and another is heterogeneous. The damage initiation, crack propagation, as well as the failure evolution, were observed. A damage parameter was defined and it was tested. One found that the damage mechanism was very different for crack initiation and crack propagation and for MMCs with different spatial particle distributions. The mechanism of MMCs failure is discussed by the ideas of shear stress transfer between matrix and reinforcement. The discussion can explain the distinct mechanism of damage and failure in SiC particulate-reinforced aluminum composites.

Yichun Zhou

Papers

Influence of Li-dopants on the luminescent and ferroelectric properties of ZnO thin films

Acoustic emission assessment of interface cracking in thermal barrier coatings

Thermal Damage in Particulate-Reinforced Metal Matrix Composites

Thermopiezoelectric response of a piezoelectric thin film PZT-6B deposited on MgO (1 0 0) substrate due to a continuous laser

Mathematical Analysis on the Uniqueness of Reverse Algorithm for Measuring Elastic-plastic Properties by Sharp Indentation