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The binary high-pressure phase diagram of the Ta–Sb system was constructed for the first time in this study, utilizing the evolutionary algorithm USPEX and density functional theory (DFT). Ten pressurized dynamically and mechanically stable or metastable novel phases of Ta–Sb were discovered, including I4/mmm-TaSb2, P4/nmm-TaSb, P-3-Ta2Sb7, I4/mmm-Ta2Sb3, P-4m2-Ta7Sb, Pm-3-Ta7Sb, Pmm2-Ta15Sb, P4/nmm-TaSb3, I4/mmm-Ta3Sb4, and I4/mmm-Ta2Sb5. The compounds P-4m2-Ta7Sb and Pmm2-Ta15Sb exhibit promising characteristics as non-centrosymmetric superconductors (NCSs), with their superconducting critical temperature (TC) being 3.831 and 3.221 K, respectively. The application of pressure tuning is predicted to transform the topological characteristics of P4/nmm-TaSb, causing it to transition from a topological insulator state to a Dirac semimetal state and ultimately reverting back to a topological insulator state. Therefore, the P4/nmm-TaSb compound is considered a promising candidate to investigate topological and superconducting excitations. Moreover, the mechanical and thermal properties of Ta–Sb binary phases were also investigated. The thermal conductivity of I4/mmm-TaSb2, P4/nmm-TaSb, and P4/nmm-TaSb3 all surpasses 20 W m−1 K−1 at 1000 K, showcasing their excellent thermal conductivity properties. The present study addresses the research gap concerning high-pressure structures in the Ta–Sb binary system, thereby offering valuable insights for the design and development of intermetallic compounds within this binary system. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) are a promising class of two-dimensional (2D) materials with tunable electronic and transport properties. In this paper, a first principles calculation of ReClI, ReClBr, and ReIBr Janus 2D materials was carried out in view of structural design and electronic properties. In addition, the structural stability and electronic characteristics of ReClI, ReClBr, and ReIBr were explored under the condition of tensile strain. The conclusions are described as follows: ReIBr maintains excellent lattice structural stability under external forces and possesses the strongest resistance to strain; ReClBr has the highest surface activity, and electrons are more likely to escape and participate in surface chemical reactions; ReClI, ReClBr, and ReIBr are two-dimensional materials that exhibit semiconductor properties while showing varying degrees of tuning under strain conditions. [ABSTRACT FROM AUTHOR]

Purpose: To develop an efficient simultaneous multislab imaging method with blipped‐controlled aliasing in parallel imaging (blipped‐SMSlab) in a 4D k‐space framework, and to demonstrate its efficacy in high‐resolution diffusion MRI (dMRI). Theory and Methods: First, the SMSlab 4D k‐space signal expression is formulated, and the phase interferences from intraslab and interslab encodings on the same physical z‐axis are analyzed. Then, the blipped‐SMSlab dMRI sequence is designed, with blipped–controlled aliasing in parallel imaging (blipped‐CAIPI) gradients for interslab encoding, and a 2D multiband accelerated navigator for inter‐kz‐shot phase correction. Third, strategies are developed to remove the phase interferences, by RF phase modulation and/or phase correction during reconstruction, thus decoupling intraslab and interslab encodings that are otherwise entangled. In vivo experiments are performed to validate the blipped‐SMSlab method and preliminarily evaluate its performance in high‐resolution dMRI compared with traditional 2D imaging. Results: In the 4D k‐space framework, interslab and intraslab phase interferences of blipped‐SMSlab are successfully removed using the proposed strategies. Compared with non–CAIPI sampling, the blipped‐SMSlab acquisition reduces the g‐factor and g‐factor‐related SNR penalty by about 12%. In addition, in vivo experiments show the SNR advantage of blipped‐SMSlab dMRI over traditional 2D dMRI for 1.3‐mm and 1.0‐mm isotropic resolution imaging with matched acquisition time. Conclusion: Removing interslab and intraslab phase interferences enables SMSlab dMRI with blipped‐CAIPI in a 4D k‐space framework. The proposed blipped‐SMSlab dMRI is demonstrated to be more SNR‐efficient than 2D dMRI and thus capable of high‐quality, high‐resolution fiber orientation detection. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to propose a novel algorithm for slab boundary artifact correction in both single‐band multislab imaging and simultaneous multislab (SMSlab) imaging. Theory and Methods: In image domain, the formation of slab boundary artifacts can be regarded as modulating the artifact‐free images using the slab profiles and introducing aliasing along the slice direction. Slab boundary artifact correction is the inverse problem of this process. An iterative algorithm based on convolutional neural networks (CNNs) is proposed to solve the problem, termed CNN‐enabled inversion for slab profile encoding (CPEN). Diffusion‐weighted SMSlab images and reference images without slab boundary artifacts were acquired in 7 healthy subjects for training. Images of 5 healthy subjects were acquired for testing, including single‐band multislab and SMSlab images with 1.3‐mm or 1‐mm isotropic resolution. CNN‐enabled inversion for slab profile encoding was compared with a previously reported method (i.e., nonlinear inversion for slab profile encoding [NPEN]). Results: CNN‐enabled inversion for slab profile encoding reduces the slab boundary artifacts in both single‐band multislab and SMSlab images. It also suppresses the slab boundary artifacts in the diffusion metric maps. Compared with NPEN, CPEN shows fewer residual artifacts in different acquisition protocols and more significant improvements in quantitative assessment, and it also accelerates the computation by more than 35 times. Conclusion: CNN‐enabled inversion for slab profile encoding can reduce the slab boundary artifacts in multislab acquisitions. It shows better slab boundary artifact correction capacity, higher robustness, and computation efficiency when compared with NPEN. It has the potential to improve the accuracy of multislab acquisitions in high‐resolution DWI and functional MRI. [ABSTRACT FROM AUTHOR]