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Unconventional metamagnetic phase transition in R_(2)In(R=Nd, Pr)with lambda-like specific heat and nonhysteresis

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Journal of Materials Science & Technology 2022年第6期101卷 80-84页

作者： Weibin cui Guiquan Yao Shengyu Sun qiang Wang Jie Zhu Sen Yang Key Laboratory of Electromagnetic Processing of Materials Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China State Key Laboratory of Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China

The phase transition of Nd_(2)In and Pr_(2)In has been studied and found to be between the first-order and second-order *** any hysteresis nor obvious cell volume changes are *** the field-triggered metamagnetism is demonstrated with lambda-like peak on specific heat *** the field change of 7 T,giant magnetic entropy changes of 13.2 J kg^(-1)K^(-1) and 19.5 J kg^(-1)K^(-1) and adiabatic temperature changes of 6.5 K and 7.4 K have been achieved in Nd_(2)In and Pr_(2) In alloys respectively,which is partially contributed by strong magnetoelastic coupling represented by high saturation magnetostriction of~450 *** unique feature is proposed to be originated from the delocalized 5d electrons,as evidenced by the negative magnetoresistance caused by the phase transition.

关键词： Metamagnetic transition Magnetic entropy change Magnetocaloric effects Magnetostriction

Enhanced hydrogen evolution reaction over molybdenum carbide nanoparticles confined inside single-walled carbon nanotubes

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Journal of Energy Chemistry 2019年第1期28卷 123-127页

作者： Tingting cui Jinhu Dong Xiulian Pan Tie Yu qiang Fu Xinhe Bao State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

Carbon nanotubes(CNTs) have shown as unique nanoreactors to tune the catalytic activity of confined nano-catalysts. Here we report that the catalytic performance of molybdenum carbide nanoparticles(MoC_x NPs) for the hydrogen evolution reaction(HER) process can be enhanced by encapsulation within single-walled carbon nanotubes(SWNTs) with a diameter of 1–2 nm. The catalyst with MoC_x NPs located on the interior surface of SWNTs(MoCx@SWNTs) exhibits a lower onset over-potential and a smaller Tafel slope than the one with MoC_x NPs attached on the exterior surface(MoCx/SWNTs). This is likely attributed to the much smaller particle size and the more reduced states of the confined MoC_x NPs, as well as the larger specific surface area of MoCx@SWNTs compared with Mo Cx/SWNTs. In addition, the electronic structure of the confined MoC_x NPs might be modified by the confinement effects of SWNTs, and hence the adsorption free energy of H atoms on the confined MoC_x NPs, which could also contribute to their higher performance. These results suggest that the SWNTs can be further explored for constructing novel catalysts with beneficial catalytic performance.

关键词： Single-walled carbon nanotubes Confined catalysis Molybdenum carbide Nanoparticles Hydrogen evolution reaction

Early Triassic Legoupil Formation in Schmidt Peninsula,Antarctic Peninsula:Provenance and Depositional Settings

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Journal of Earth Science 2024年第2期35卷 317-331页

作者： Chao Zhang Ying-Chun cui Chen-Guang Liu Fang-Hua cui Lu-Yuan Wang Wei-qiang Zhang School of Resources and Environmental Engineering Shandong University of TechnologyZibo255049China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai201209China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyState Oceanic AdministrationQingdao266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao266061China Key Laboratory of Mineral Resources Evaluation in Northeast Asia Ministry of Land and ResourcesChangchun130061China

Geochemical compositions can be used to determine the tectonic setting of sedimentary basins,while where the link of source to sink is no longer preserved,detrital zircon age patterns can aid in resolving the original basin *** metasedimentary Legoupil Formation,located at Cape Legoupil and the Schmidt Peninsula,could give a hint for the tectonic evolution of Antarctic *** this contribution,we constrain the sedimentary provenance of the Legoupil Formation through geochemistry and detrital zircon U-Pb *** petrography and geochemical features indicate that the provenance of the Legoupil Formation could be felsic *** zircon grains record a steady supply of Permian and Ordovician material into the Legoupil *** youngest concordant zircon ages of 262 Ma suggest that the depositional time of Legoupil Formation is no older than Late *** detrital zircon age spectrum of Legoupil Formation suggests that the Legoupil Formation sediments should be derived from regional sources endemic to western Gondwana prior to its *** with the previous studies,geochemistry and detrital zircons reflect an active continental margin tectonic setting and the detrital zircon spectra of Legoupil Formation are similar to the ones deposited in forearc tectonic setting.

关键词： Schmidt Peninsula Legoupil Formation Trinity Peninsula Group detrital zircons Antarctic Peninsula geochemistry

Progress on elliptical magnetic skyrmions

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Rare Metals 2023年第2期42卷 359-367页

作者： Bao-Shan cui Yong-qiang Yang Xiao-Bin Guo Shi-Heng Liang Hao Wu Guo-qiang Yu Songshan Lake Materials Laboratory Dongguan523808China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China Faculty of Physics and Electronic Science Hubei UniversityWuhan430062China School of Physics&Optoelectric Engineering Guangdong University of TechnologyGuangzhou510006China

Magnetic skyrmions,the topological spin textures firstly observed in chiral magnets,have aroused huge interest due to their emergent electromagnetism and potential applications in *** the last decade,significant efforts have been devoted to skyrmion generation,stabilization,and *** most cases,the theoretical and experimental investigations have been performed in the materials where the skyrmions have a circular *** we know,magnetic anisotropy(K_(u))and Dzyaloshinskii-Moriya interaction(DMI)play key roles in the stabilization of the skyrmions in chiral ***,modifying the Kand DMI provide new degrees of freedom for studying the related physics and applications of skyrmions in addition to engineering their energetics and *** this review,the latest progress on the study of the anisotropic deformation of magnetic skyrmions(i.e.,elliptical magnetic skyrmions)is *** physical origins and important advantages of elliptical magnetic skyrmions are mainly focused *** review gives an insight into the understanding of the physical mechanisms of elliptical magnetic skyrmion-hosting systems.

关键词： Dzyaloshinskii-Moriya interaction(DMI) Elliptical magnetic skyrmion Magnetic anisotropy(K_(u)) Skyrmion Hall effect

Expression and effect of proline hydroxylase domain 2 in retina of diabetic rats

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International Journal of Ophthalmology(English edition) 2016年第3期9卷 357-362页

作者： Zhen Li Yi-Qiao Xing Wei cui qiang Lu Department of Ophthalmology Renmin Hospital of Wuhan University Wuhan 430060 Hubei Province China Department of Ophthalmology Inner Mongolia People's Hospital Hohhot 010017 Inner Mongolia Autonomous Region China

AIM： To observe the expression of proline hydroxylase domain 2 （PHD2） in the retina of diabetic rats and investigate the relationship between PHD2 and relevant intraocular vascular proliferation factors, METHODS： Sixty male specific pathogen free （SPF） Sprague-Dawley （SD） rats were randomly divided into two groups： the diabetic group and the control group. The rats in the diabetic group were intraperitoneally injected with 60 mg/kg （0.60 mL/100 g） of streptozotocin to induce a diabetic rat model. The rats in the control group were injected with an equal volume of sodium citrate buffer solution by the same method. Hematoxylin- eosin （HE） staining and immumofiuorescence （IF） method were adopted to observe the pathological changes of retinal tissues and the expression of PHD2, glial fibrillary acidic protein （GFAP）, vascular endothelial growth factor （VEGF） by 8wk. RT-PCR method was applied to detect the expressions of mRNA of PHD2, VEGF and GFAP. The relationship between PHD2 and other vascular proliferation factors was analyzed. RESULTS： HE staining showed that there was the retinal tissue edema in the diabetic group, and the arrangement was in disorder, and proliferation could be seen. IF staining： in the retina of normal rats, PHD2 was not expressed, GFAP and VEGF were mainly expressed in astrocytes; while in the diabetic rats, PHD2, GFAP and VEGF staining showed strong positivity in all retinal layers, mainly in neurogliocytes. PHD2 was co-expressed with VEGF and GFAP. The mRNA expression levels of PHD2, GFAP and VEGF in the diabetic group were obviously higher than that in the control group, respectively 1.83 times, 1.75 times and 2.08 times. The difference had statistical significance （P〈0.01）. CONCLUSION： The high expression of PHD2 in the retina of early-stage diabetic rats might result from secretion of neurogliocytes induced by local high- concentration blood glucose, thus promoting the expression of VEGF and GFAP, PHD2 plays an important role during the occ

关键词： proline hydroxylase domain 2 diabeticretinopathy retinal neovascularization

Phase field modeling of multiple dendrite growth of Al-Si binary alloy under isothermal solidification

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China Foundry 2008年第4期5卷 265-267页

作者： Sun qiang Zhang Yutuo cui Haixia Wang Chengzhi Shenyang Ligong University Shenyang 110168 China

Phase field method offers the prospect of being able to perform realistic numerical experiments on dendrite growth in metallic systems. In this study, the growth process of multiple dendrites in AI-2-mole-%-Si binary alloy under isothermal solidification was simulated using phase field model. The simulation results showed the impingement of arbitrarily oriented crystals and the competitive growth among the grains during solidification. With the increase of growing time, the grains begin to coalesce and impinge the adjacent grains. When the dendrites start to impinge, the dendrite growth is obviously inhibited.

关键词： phase field model multiple dendrite growth binary alloy isothermal solidification

Experiment Study on Shock Induced Reaction Process of Ti+Si Reactive Powder

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Journal of Beijing Institute of Technology 2017年第3期26卷 292-296页

作者： naifu cui Pengwan Chen qiang Zhou Bingbing Zhou State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

A phenomenon of shock wave reacceleration was studied when Ti＋Si reactive powder is loaded by a high-speed *** self-propagating reaction in the Ti＋Si reactive powder was triggered by the high speed impaction of the flyer launched by a two-stage gas *** the process of self-propagating reaction,a strand of optical fiber and the electric pins were used to measure the velocity of shock wave *** experimental results showed that the initial velocity of shock wave in the reactive powder was a few hundred meters per second,and then it decreased obviously with the increase of propagation *** phenomenon was also verified in the process of a pure Si powder loaded by a shock,while the phenomenon of shock wave reacceleration was not observed in the Ti＋Si reactive powder.

关键词： reactive powder electric pin optical fiber shock wave combustion wave

The effect of hydrogen peroxide on properties of Ce0.35Zr0.55La0.055Pr0.045O2 oxides and the catalytic performance usedon Pd supported three-way catalyst

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Journal of Rare Earths 2017年第11期35卷 1092-1101页

作者： Qi wang Meisheng cui Xiaowei Huang Yongke Hou Mei Yue qiang Zhong YongqiZhang General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Co. Ltd Beijing 100088 China

In this study,two series of cerium zirconium mixed oxides CeZrLaPrOwere prepared under traditional co-precipitation and oxidation co-precipitation methods respectively. The physicochemical properties of the samples were compared under these two methods and assessed by XRD,Raman,BET,TEM,HTPR,OSC,XPS and catalysts measurements. The formation of homogeneity phase structure can be facilitated by changing the precipitating properties of Ce3+ under oxidation coprecipitation method, which is helpful to enhance the homogeneity of Ce and Zr at atomic ***’s more, it is conducive to remove impurities Na~+ and Cl~-by oxidation co-precipitation with hydrogen peroxide. The catalysts activities are related to both the redox properties and the textural properties of mixed oxides. The Pd-only TWCs supported on the CZLP-H-F exhibits better catalytic performance and thermal stability with wider air/fuel ratio operation window, lower light-off and full conversion temperatures of CHand NO. The homogeneity of phase structure for cerium zirconium mixed oxide can be predicted and deduced from detecting the atomic distribution uniformity of its precursor. So this work not only provides insights into the mechanisms for phase segregation of cerium zirconium mixed oxide, but also provides a guidance to improve homogeneity of cerium zirconium mixed oxide by adding additives.

关键词： Cerium zirconium mixed oxides Co-precipitation Hydrogen peroxide Catalytic performance

Morphology evolution and crystallographic feature of Nb nanowire in an in-situ NiTi-Nb nanocomposite

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Rare Metals 2014年第5期33卷 563-567页

作者： Zhen-Yang Liu Fang-Min Guo Zhong-qiang Wang Li-Shan cui Department of Materials Science and Engineering China University of Petroleum

In–situ NiTi shape memory alloy–Nb nanowire nanocomposite was revealed to exhibit exceptional mechanical properties. The properties of high strength and ultra-large elastic strains are closely related with the high performance of in situ-formed Nb nanowire reinforcements. In this study, the morphology evolution and crystallographic feature of Nb nanowires in NiTi shape memory alloy matrix during cold drawing were investigated by means of transmission electron microscopy（TEM）. It is revealed that, as a result of the severe work hardening and amorphization of NiTi matrix, the cold work reduction of nanowire reinforcements can exceed that of the entire composite. The irregular-shaped Nb nanowires are reshaped to straight and smooth nanowires during cold drawing process. By means of TEM nanobeam diffraction,it is revealed that the in situ-formed Nb nanowire in such top-down processed NiTi–Nb composite keeps single crystalline over 1,000 nm at length direction. As a consequence, the aspect ratio of nanowire reinforcements in NiTi matrix exceeds 25：1.

关键词： Deep drawing Nanowire Metal matrix composite TEM