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Observational appearance and extra photon rings of an asymmetric thin-shell wormhole with a Bardeen profile

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Chinese Physics C 2024年第6期48卷 211-221页

作者：何柯腱罗智郭森李国平 Department of Physics Chongqing UniversityChongqing 401331China Guangxi key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China School of Physics and Astronomy China West Normal UniversityNanchong 637000China

In this work,the optical appearance of an asymmetric thin-shell wormhole with a Bardeen profile is *** initiate the process,we need to construct an asymmetric thin-shell wormhole utilizing the cut-and-paste technique proposed by Visser and subsequently ascertain its pertinent physical quantities such as the radius of the photon sphere and critical impact parameters for different values of magnetic charge ***,the effective potential and motion behavior of photons are also investigated within the framework of asymmetric thin-shell wormholes with a Bardeen *** can be found that the effective potential,ray trajectory,and azimuthal angle of the thin-shell wormhole exhibit a strong correlation with the mass ratio of black *** considering the accretion disk as the sole background light source,we observe additional photon rings and lensing bands in the optical appearance of the asymmetric thin-shell wormhole with a Bardeen profile compared to those exhibited by the Bardeen black *** can find that there is an increase in the size of the specific additional light bands with increasing magnetic charge g,which is different from the black hole *** exceptionally luminous rings can serve as a robust criterion for the identification and characterization of the thin-shell wormhole spacetime.

关键词： shadow asymmetric thin-shell wormhole Bardeen black hole

Control of temperature dependent viscosity for manufacturing of Bi-doped active fiber

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International Journal of Extreme Manufacturing 2024年第3期6卷 522-530页

作者： Rui Duan Jingfei Chen Hao ke Tianxia Wei ke Zhang Xueliang li Xu Feng Qiuju Zheng Zhixue He Jianrong Qiu Shifeng Zhou State key Laboratory of Luminescent Materials and Devices School of Materials Science and EngineeringSouth China University of TechnologyGuangzhou 510640People’s Republic of China Guangdong Provincial key Laboratory of Fiber Laser Materials and Applied Techniques Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesGuangzhou 510640People’s Republic of China School of Materials Science and Engineering Qilu University of TechnologyJinanPeople’s Republic of China Peng Cheng Laboratory Shenzhen 518000People’s Republic of China College of Optical Science and Engineering State Key Laboratory of Modern Optical InstrumentationZhejiang UniversityHangzhou 310027People’s Republic of China

Bi-activated photonic materials are promising for various applications in high-capacity telecommunication,tunable laser,and advanced bioimaging and *** various Bi-doped material candidates have been explored,manufacturing of Bi heavily doped fiber with excellent optical activity remains a long-standing ***,a novel viscosity evolutional behavior mediated strategy for manufacturing of Bi-doped active fiber with high dopant solubility is *** intrinsic relation among the evolution of Bi,reaction temperature and viscosity of the glass system is ***,the effective avenue to prevent the undesired deactivation of Bi during fiber drawing by tuning the temperature dependent viscosity evolution is *** applying the strategy,for the first time we demonstrate the success in fabrication of heavily doped Bi active ***,the principal fiber amplifier device is constructed and broadband optical signal amplification is *** findings indicate the effectiveness of the proposed temperature dependent viscosity mediated strategy for developing novel photonic active fiber,and they also demonstrate the great potential for application in the next-generation high-capacity telecommunication system.

关键词： infrared luminescence active fiber optical amplification

AB_(2)-type rare earth-based compounds with C-15 structure:Looking for reversible hydrogen storage materials

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Journal of Rare Earths 2024年第5期42卷 803-816,I0001页

作者： Hao Shen Junxian Zhang Valerie Paul-Boncour ping li Zhinian li Yuanfang Wu lijun Jiang National Engineering Research Center of Nonferrous Metals Materias and Products for New Energy GRINM Group Co.LtdBeijing00088China Univ Paris Est Creteil CNRSICMPEUMR 71822 rue Henri Dunant94320ThiaisFrance Institute for Advanced Materials and Technology University of Science and TechnologyBeijing100083China GRIMAT Engineering Institute Co. Ltd.Beijing101407China

AB_(2)-type(A=rare earth,B=transition metal)intermetallic compounds with C15 structure can easily absorb large amount of hydrogen,showing their potential use as hydrogen storage *** crucial problem hindering their application is hydrogen induced amorphization(HIA),which leads to the irreversible hydrogen sorption *** stability of the AB_2 Laves phase compounds,the structural properties,the hydrogenation properties and the controlling factors of HIA are discussed in this *** with other factors,the atomic radii ratio r_A/r_B is the most important one influencing the ***-element substitution is an efficient way to suppress or limit HIA and may enable AB_2 compounds to be suitable for hydrogen storage.

关键词： Rare earth-based AB_2-type compounds Hydrogenation properties Hydrogen induced amorphization Elemental substitution

A general synthetic strategy for N, P co-doped graphene supported metal-rich noble metal phosphides for hydrogen generation

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Green Energy & Environment 2024年第1期9卷 152-162页

作者： Jingwen Ma Xiang li Guangyu Lei Jun Wang Juan Wang Jian liu Ming ke Yang li Chunwen Sun School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing100083China State key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Lab of Advanced Nano-structures&Transfer Processes Department of Chemical EngineeringTianjin UniversityTianjin300354China PetroChina Planning and Engineering Institute Beijing100083China

The exploitation of electrocatalysts with high activity and durability for HER is desirable for future energy systems,but it is still a *** have attracted increasing attentions,but the preparation process often needs toxic regents or dangerous reaction ***,we develop a general green method to fabricate metal-rich NMPs anchored on NPG through pyrolyzing DNA cross-linked *** obtained Ru_(2) P-NPG exhibits an ultrasmall overpotential of 7 mV at 10 mA cm^(2) and ultralow Tafel slope of 33 mV dec^(-1) in 1.0 mol L?1 KOH,even better than that of commercial Pt/*** addition,Ru 2 P-NPG also shows low overpotentials of 29 and 78 mV in 0.5 mol L^(-1) H_(2)SO_(4) and 1.0 mol L^(-1) PBS,*** superior activity can be attributed to the ultrafine dispersion of Ru 2 P nanoparticles for more accessible sites,more defects formed for abundant active sites,the two-dimensional plane structure for accelerated electron transfer and mass transport,as well as the regulation of electron distribution of the ***,the synthetic method can also be applied to prepare other metal-rich noble metal phosphides(Pd_(3)P-NPG and Rh_(2)P-NPG),which also exhibits high activity for *** work provides an effective strategy for designing NMP-based electrocatalysts.

关键词： Noble metal phosphides Electrocatalyst Deoxyribonucleic acid Hydrogen evolution pH universal

Electrochemical Cascade Annulation for the Synthesis of 3-Sulfanylquinoline Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2024年第16期42卷 1833-1838页

作者： ke li Ming-Zhong Guo Zhuo Chen Hao-Ran li Weisi Guo Ming li lin-Bao Zhang State key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong 266042China

An efficient electrochemical approach has been developed for the construction of 3-sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided *** protocol provided a convenient route to functionalized quinolines with good functional group ***,it does not require any metal catalysts or additives,furnishing a series of biologicalquinolines inmoderatetogoodyields.

关键词： Electrocatalysis Electrooxidation Annulation 3-Sulfany quinoline C3-thioetherification

Mechanical property and thermal shock behavior of tungsten-yttria-stabilized zirconia cermet fabricated by spark plasma sintering

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Tungsten 2024年第1期6卷 134-140页

作者： lin-Chao Zhang ke Jing Rui liu Zhuo-Ming Xie Jun-Feng Yang Gang li Xian-ping Wang Xue-Bang Wu Qian-Feng Fang Chang-Song liu key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China Science and Technology on Reactor Fuel and Materials Laboratory Nuclear Power Institute of ChinaChengdu 610041China

The cermet fuels have been considered as a potential key component for the nuclear thermal propulsion,and the homogeneity of the fuel particles in the metal matrix plays a crucial role in stabilizing the structure at extremely high *** this work,liquid paraffin was used as additive to improve the distribution of yttria-stabilized zirconia(YSZ,an appropriate surrogate for UO_(2) fuel)microspheres in the tungsten(W)matrix,and the W-YSZ cermet wafers(volume ratio 1:1)with a relative density of 97.6%were fabricated by spark plasma sintering with a specifically designed *** effects of the paraffin dosage(0-5 wt.%)on the homogeneity,microstructure,mechanical properties,and the thermal conductivity of W-YSZ cermet were *** W-YSZ sample with 2 wt.%paraffin shows the highest homogeneity and exhibits the best comprehensive properties,including the ultimate tensile strength of 132.2 MPa at 600℃,the bending strength of455 MPa and thermal conductivity of 50 W·m^(-1)·K^(-1)at room ***,the cermet could keep structurally sound after thermal shocked at a heat load of 20 MW·m^(-2).These results would be helpful for the design and optimization of the cermet fuels in the nuclear thermal propulsion.

关键词： Nuclear thermal propulsion Tungsten Cermet liquid paraffin Thermal shock

Bone marrow-derived mesenchymal stem cell-derived exosomeloaded miR-129-5p targets high-mobility group box 1 attenuates neurological-impairment after diabetic cerebral hemorrhage

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World Journal of Diabetes 2024年第9期15卷 1979-2001页

作者： Yue-Ying Wang ke li Jia-Jun Wang Wei Hua Qi liu Yu-Lan Sun Ji-ping Qi Yue-Jia Song Department of Pathology The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina Department of Endocrinology The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Diabetic intracerebral hemorrhage(ICH)is a serious complication of *** role and mechanism of bone marrow mesenchymal stem cell(BMSC)-derived exosomes(BMSC-exo)in neuroinflammation post-ICH in patients with diabetes are *** this study,we investigated the regulation of BMSC-exo on hyperglycemia-induced *** To study the mechanism of BMSC-exo on nerve function damage after diabetes complicated with cerebral *** BMSC-exo were isolated from mouse BMSC *** was followed by transfection with microRNA-129-5p(miR-129-5p).BMSC-exo or miR-129-5poverexpressing BMSC-exo were intravitreally injected into a diabetes mouse model with ICH for in vivo analyses and were cocultured with high glucoseaffected BV2 cells for in vitro *** dual luciferase test and RNA immunoprecipitation test verified the targeted binding relationship between miR-129-5p and high-mobility group box 1(HMGB1).Quantitative polymerase chain reaction,western blotting,and enzyme-linked immunosorbent assay were conducted to assess the levels of some inflammation factors,such as HMGB1,interleukin 6,interleukin 1β,toll-like receptor 4,and tumor necrosis factorα.Brain water content,neural function deficit score,and Evans blue were used to measure the neural function of *** Our findings indicated that BMSC-exo can promote neuroinflammation and functional *** chip analysis of BMSC-exo identified miR-129-5p as the specific microRNA with a protective role in *** of miR-129-5p in BMSC-exo reduced the inflammatory response and neurological impairment in comorbid diabetes and ICH ***,we found that miR-129-5p had a targeted binding relationship with HMGB1 *** We demonstrated that BMSC-exo can reduce the inflammatory response after ICH with diabetes,thereby improving the neurological function of the brain.

关键词： Bone marrow mesenchymal stem cells Exosome Diabetic cerebral hemorrhage Neuroinflammation MicroRNA-129-5p High mobility group box 1

Energy Absorption by 3D-Printed Mesh Structures with a Negative Poisson’s Ratio

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 205-212页

作者： Wenyu li Weiming Yang Mingze li Xiang Zhang ping Zhang Yucheng Zhao Peijian Chen Haishun liu School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou221116China School of Materials Sciences and Physics China University of Mining and TechnologyXuzhou221116China

A negative Poisson's ratio(NPR)structure represents optimal impact-resistance with applications in various fields,including the crash box in vehicles,which absorbs impact kinetic *** crash box is designed to deform in response to impact,increasing local structural density,which enhances impact resistance *** studies have only focused on the NPR effect in the plane dimension at low-speed *** studies have considered high-speed impact loads on three-dimensional NPR *** have developed two types of AlSi10Mg alloy energy-absorbing structures with NPR using three-dimensional printing technology,and have compared our systems with a conventional hexagonal mesh *** testing involved split-Hopkinson pressure bar measurements,which showed good agreement with dynamic numerical *** subjected to an impact load,the NPR structure exhibited better impact resistance and energy absorption compared with the positive Poisson's ratio *** proposed dual-layer hexagonal structure ensures an NPR effect while exhibiting higher strength and improved stability relative to the conventional concave hexagon structure.

关键词： Negative Poisson’s ratio Energy absorption 3D printing Split-Hopkinson pressure bar Numerical simulation

Optimization on magnetic properties of Nd-doped Fe_(3)O_(4) nanoparticles for magnetic shielding fabrics

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Journal of Rare Earths 2024年第4期42卷 683-689页

作者： Xiaolei Song Congzhu Xu Yuyan Wang Huizhen ke Yonggui li Qufu Wei Xinqun Feng Faculty of Clothing and Design Minjiang UniversityFuzhou350108China Fujian key Laboratory of Novel Functional Textile Fibers and Materials Minjiang UniversityFuzhou350108China College of Textile and Clothing Jiangnan UniversityWuxi214122China College of Fashion and Design Donghua UniversityShanghai201620China

High magnetic protective fabrics with rare earth Nd doped Fe_(3)O_(4) nanoparticles were fabricated via a grafting *** structure,crystal form,and elemental composition of nanoparticles were investigated by transmission electron microscopy,energy dispersive X-ray,X-ray powder diffraction,and X-ray photoelectron *** obtained NdFe_(2)O_(4) nanoparticles show spherical shape with fine dispersion and reasonable element ***,they demonstrate fine superparamagnetic properties with a magnetic saturation value of 29.25 A·m^(2)/g and low coercivity of 1.902 mT through the vibrating sample magnetometry technique,which can be well developed in magnetic shielding protective ***,the cotton fabrics with plain weave were finished by a proofing rapier loom as a *** NdFe_(2)O_(4) nanoparticles underwent some appropriate surface modification and then were grafted onto the cotton fabrics by a bridge agent of N,N’-dissuccinimidyl *** morphology,structure,dispersion effect,and electromagnetic protective properties of the fabrics were observed through scanning electron microscopy,Fourier infrared spectroscopy,thermogravimetric analysisdifferential scanning calorimetry(TG-DSC),and a vector network *** reliable fabrics with grafting reaction on the interface are expected to have potential applications in the field of electromagnetic protection and biomedicine fields.

关键词： Magnetic property Nd Fe_(3)O_(4)nanoparticles Magnetic shielding Fabrics Rare earths