Search

Your search keyword '"He, Xijia"' showing total 115 results
Start Over Author "He, Xijia"
115 results on '"He, Xijia"'

31. Effect of Cu Doping on Phase Transition, Thermal Strain, and Thermal Expansion Property in Polycrystalline Ni50Mn23−xCuxGa27 Alloys.

Author

Wei, Shengxian, Hu, Fene, Deng, Liping, Yue, Bao, Cao, Yiming, He, Xijia, Zhang, Yuanlei, Kang, Yanru, Xu, Kun, and Li, Zhe

Subjects
PHASE transitions, THERMAL strain, COPPER, THERMAL expansion, TRANSITION metals, THERMAL properties, GALLIUM alloys, IRON-manganese alloys
Abstract

The influence of Cu doping on phase transition, thermal strain, and thermal expansion property of polycrystalline Ni50Mn23−xCuxGa27(x = 1, 3, 5, 6 and 7) alloys is investigated. The results show that with increasing Cu concentration, martensitic transformation gradually gets close to Curie transition. A magnetostructural transition (MST) is observed in samples with x = 6 and 7. Such MST can enhance magnitude of transformation strain. Besides, Ni50Mn23−xCuxGa27 alloys possess an isotropic, recoverable, and thermally stable thermal strain. Excitedly, Cu doping can effectively tune the phase transition, thermal strain, and thermal expansion properties of Ni50Mn23−xCuxGa27 alloys. Adjustable coefficients of thermal expansion from positive to negative are obtained by Cu‐doped Ni50Mn23−xCuxGa27 alloys. The average linear expansion coefficient (α) between −140.44 and −207.70 ppm K−1 is observed in samples with x = 6 and 7 for a narrow temperature span of 11–14 K. When the temperature span is about 72 K (x = 6) and 73 K (x = 7), which is the largest temperature span observed in Ni–Mn–Ga‐based alloys recently, the α values decrease to about −36 ppm K−1. These findings are beneficial for manipulating the thermal expansion property of Ni–Mn–Ga–Cu alloys and their multifunctional applications. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

36. An Intelligent Information Management System for Retinal Image Storage and Recognition in Chronic Disease using Digital Signal and Image Processing

Author

Anil Sharma, Xiaojun Xu, Haixuan Wang, Tang Zhong, and He Xijia

Subjects
Hypertext Transfer Protocol, Computer science, business.industry, computer.internet_protocol, ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, Digital imaging, Image processing, Communications system, Computer Science Applications, Theoretical Computer Science, DICOM, Digital image, Picture archiving and communication system, Artificial Intelligence, health services administration, Digital signal, Computer vision, Artificial intelligence, business, computer, Software
Abstract

Retinal imaging plays a very significant role in the study of retinal vasculature changes indicative of chronic disease information related to vision. This study investigates the invulnerability of retinal image information in the disease information system and assesses the quantitative method of the morphological changes in the retinal vascular network. In this work, the medical digital image transmission protocol Digital Imaging & Communications in Medicine (DICOM) version 3.0 and the retinal image Picture Archiving & Communication System (PACS) were constructed in the laboratory using browser/server mode. Also, the DICOM-SR document was designed in this article using a list or hierarchy, and the retinal images to report the information of patients by using the Hypertext Transfer Protocol (HTTP) – based Web Access to DICOM Persistent Objects (WADO) approach. The results showed that the retinal image PACS system constructed in Browser/Server mode can effectively store and transmit DICOM images. When the imaging device is combined with the application program, special adapters are used to negotiate the transmission syntax. The message flow is decoded in the communication process, which can be connected with the realization to improve the efficiency of information collection. The proposed PACS system integrates the quantitative features of retina providing more meaningful research data for data mining in comparison to the traditional state of the art methods based on chronic disease management system. The diagnostic ability of the retinal imaging procedure using the DICOM images is justified by obtaining 98.51%, 98.04%, 99% and 99.01% of accuracy, sensitivity, specificity and precision values respectively.

Published
2021
Full Text
View/download PDF

43. Achievement of a reversible giant magnetocaloric effect via exerting external hydrostatic pressure on a Ni45Co5Mn35In15 metamagnetic Heusler alloy.

Author

He, Xijia, Zhang, Yuanlei, Wei, Shengxian, Cao, Yiming, Xu, Kun, and Li, Zhe

Subjects
*MAGNETOCALORIC effects, *MANGANESE alloys, *HEUSLER alloys, *HYDROSTATIC pressure, *FIRST-order phase transitions, *MAGNETIC fields
Abstract

Magnetocaloric materials with first-order phase transition are potential refrigerant media for solid state refrigeration. In this work, the Ni45Co5Mn35In15 alloy possesses a representative first-order martensitic transition (MT), which is found to be sensitive to both magnetic field and isostatic pressure with rates of ∼−6.4 K T−1 and ∼4.24 K kbar−1. Such an active response to multi-stimuli derives from the strong coupling of the spin and the lattice. A low magnetic field of 1 T can drive nearly 100% of the total entropy change corresponding to the whole transformation in this alloy. However, the prominent magnetocaloric effect (MCE) is almost irreversible owing to the intrinsic hysteresis of the first-order phase transition. By virtue of the strong magnetostructural coupling during the MT, a hydrostatic pressure assisted magnetic field loading loop has been constructed for eliminating the hysteresis and to a large extent improve the reversibility of the MCE. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

48. Electrical transport properties and giant baroresistance effect at martensitic transformation of Ni43.7Fe5.3Mn35.4In15.6 Heusler alloy.

Author

Zhang, Yuanlei, He, Xijia, Li, Zhe, Xu, Kun, Liu, Changqin, Huang, Yinsheng, and Jing, Chao

Subjects
*MARTENSITIC transformations, *HYDROSTATIC pressure, *CONDENSED matter physics, *MICROSTRUCTURE, *CRYSTAL structure
Abstract

The electrical transport properties at martensitic transformation (MT) in polycrystalline Ni43.7Fe5.3Mn35.4In15.6 have been intensively investigated under different hydrostatic pressures. For this alloy, the experimental results show that applying a higher hydrostatic pressure can convert its MT from the metamagnetic type into the paramagnetic type. It provides a unique opportunity to separate the relative contributions of electron-spin and electron-lattice scatterings across the metamagnetic MT based on the dynamical Clausius-Clapeyron equation, which delivers a deeper insight into the resistivity change of metamagnetic MT for the Mn-rich Ni-Mn based Heusler alloys. In addition, the studied alloy also reveals a giant positive baroresistance (BR) effect with a saturated value of 115% at 242 K. This performance originates from the combined effect of electron-spin and electron-lattice scatterings associated with a prominent hydrostatic pressure-induced MT, which contribute 46% and 69% to the overall BR ratio, respectively. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results