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Magnetic Switching Dynamics and Tunnel Magnetoresistance Effect Based on Spin-Splitting Noncollinear Antiferromagnet Mn_(3)Pt

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Chinese Physics Letters 2024年第4期41卷 132-138页

作者：朱蒙董建艇李新录郑凡星周晔吴琨张佳 School of Physics and Wuhan National high Magnetic field Center Huazhong University of Science and TechnologyWuhan 430074China

In comparison to ferromagnets,antiferromagnets are believed to have superior advantages for applications in next-generation magnetic storage devices,including fast spin dynamics,vanishing stray fields and robust against external magnetic field,***,unlike ferromagnetic orders,which could be detected through tunneling magnetoresistance effect in magnetic tunnel junctions,the antiferromagnetic order(i.e.,Néel vector)cannot be effectively detected by the similar mechanism due to the spin degeneracy of conventional *** discovered spin-splitting noncollinear antiferromagnets,such as Mn_(3)Pt with momentum-dependent spin polarization due to their special magnetic space group,make it possible to achieve remarkable tunneling magnetoresistance effects in noncollinear antiferromagnetic tunnel *** first-principles calculations,we demonstrate that the tunneling magnetoresistance ratio can reach more than 800% in Mn_(3)Pt/perovskite oxides/Mn_(3)Pt antiferromagnetic tunnel *** also reveal the switching dynamics of Mn_(3)Pt thin film under magnetic fields using atomistic spin dynamic *** study provides a reliable method for detecting Néel vector of noncollinear antiferromagnets through the tunnel magnetoresistance effect and may pave its way for potential applications in antiferromagnetic memory devices.

关键词： tunneling magnetoresistance momentum

The behaviors of gas-liquid two-phase flow under gas kick during horizontal drilling with oil-based muds

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Petroleum 2024年第1期10卷 49-67页

作者： Yu Su Huiyun Ma Jianhua Guo Xinyu Shen Zhaoliang Yang Jie Wu Engineering Technology research Institute PetroChina Southwest Oil & Gas Field Company

Natural gas is easily soluble in oil-based muds(OBM), leading to complex flow behavior in wellbores,especially in horizontal wells. In this study, a new transient flow model considering wellbore-formation coupling and gas solubility on flow behavior is developed to simulate gas kicks during horizontal drilling with OBM. Furthermore, the effect of gas solubility on parameters such as bottom-hole pressure(BHP),gas void fraction and mixture velocity in the flow behavior is analyzed. Finally, several critical factors affecting flow behavior are investigated and compared to gas kicks in water-based muds(WBM) where the effect of solubility is neglected. The results show that the invading gas exists as dissolved gas in the OBM and as free gas in the WBM. Before the gas escapes from the OBM, the pit gain is zero and there is barely any change in the BHP, annulus return flow rate and mixture velocity, which means that detecting gas kicks through these warning signs can be challenging until they get very close to the surface and develop rapidly. However, in WBM drilling, these parameters change quickly with the increasing gas kick time. Additionally, for both cases, the longer the horizontal length and the greater reservoir permeability,the greater the decrease in BHP, and the shorter the time for gas to migrate from the bottom-hole to the wellhead. A larger flow rate contributes to a greater initial BHP and a lesser BHP reduction. This research is of value in characterizing gas kick behavior and identifying novel ways for early gas kick detection during horizontal drilling with OBM.

关键词： Flow behavior Gas solubility Gas kick Horizontal drilling Oil-based muds Water-based muds

Morphological and molecular description of a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,India

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Asian Pacific Journal of Tropical Medicine 2024年第5期17卷 226-234页

作者： Prasanta Saini Harish Kumar Shah Mathew Jessu Sonia T Tom Anns KP Amju ICMR-Vector Control research Centre(field Station) KottayamKeralaIndia

Objective:To report a new species of sandfly,Sergentomyia(Neophlebotomus)ashwanii ***.(Diptera:Psychodidae)from Western Ghats,***:A systematic sandfly survey was conducted in the Thrissur and Kollam districts of Kerala,India using mechanical aspirators,light and sticky traps,both indoor and outdoor habitats,for a period of one *** acid barcoding of samples was performed targeting mitochondrial cytochrome oxidase I(COI)gene and sequence generated was subjected to phylogenetic ***:Sergentomyia(Neophlebotomus)ashwanii,a new sandfly species is recorded and described in this communication.A single row of 10-12 pointed teeth in the cibarium with 4-6 small denticles or fore-teeth are the key characteristics that is distinctive from other members of the subgenus *** COI barcode followed by phylogenetic analysis of the nucleotide sequence confirms that specimens of the species belong to the same taxonomic group while the genetic distance(14.2%)with the congeners established it to be a different ***:The Western Ghats'being an important biodiversity hotspot and has dearth of systematic entomological surveys on *** current study tried to fill the void and also report a new sandfly species.

关键词： Sergentomyia(Neophlebotomus)ashwanii COI barcode Western Ghats Phlebotomine sandflies

Hole mobility enhancement in monolayer WSe2 p-type transistors through molecular doping

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Science China(Information Sciences) 2024年第6期67卷 207-213页

作者： Shiyuan LIU Xiong XIONG Xin WANG Xinhang SHI Ru HUANG Yanqing WU School of Integrated Circuits and Beijing Advanced Innovation Center for Integrated Circuits Peking University Wuhan National high Magnetic field Center and School of Integrated Circuits Huazhong University of Science and Technology

Two-dimensional （2D） transition metal dichalcogenide （TMDC） semiconductor materials exhibit extraordinary electrical properties,holding promise for the realization of next-generation complementary metal-oxide-semiconductor （CMOS） devices at ultimate ***,constrained by effective device doping strategies,the hole mobility and device performance of tungsten diselenide （WSe2） p-type transistors,especially monolayer chemical vapor deposition （CVD）-grown WSe2,have not met *** this paper,an effective performance enhancement of monolayer WSe2p-type transistor was achieved through a molecular doping *** monolayer WSe2directly on SiO2back-gated substrates and leveraging energy band alignment design,4-nitrobenzenediazonium tetrafluoroborate （4-NBD） molecular dopant with a concentration of 10 m M was utilized to modulate the Fermi level position of monolayer WSe2for hole *** devices demonstrated a more than 98%increase in hole mobility,reaching up to 97 cm2·V-1·s-1while maintaining the current on/off ratio of *** p-type WSe2transistors with 1μm channel length exhibit a high drive current surpassing 176μA·μm-1,exceeding previous CVD-WSe2devices with similar channel *** straightforward and effective approach to improving the electrical performance of WSe2transistors paves the way for advanced logic technologies based on transition metal dichalcogenide semiconductors.

关键词： CVD-grown WSe$_2$ molecular doping 4-NBD p-type transistors hole mobility

Acetaminophen overdose-induced acute liver injury can be alleviated by static magnetic field

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Zoological research 2024年第3期45卷 478-490页

作者： Han-Xiao Chen Xin-Yu Wang Biao Yu Chuan-Lin Feng Guo-Feng Cheng Lei Zhang Jun-Jun Wang Ying Wang Ruo-Wen Guo Xin-Miao Ji Wen-Jing Xie Wei-Li Chen Chao Song Xin Zhang CAS Key Laboratory of high Magnetic field and Ion Beam Physical Biology High Magnetic Field LaboratoryHefei Institutes of Physical ScienceChinese Academy of SciencesHefeiAnhui 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefeiAnhui 230026China Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China

Acetaminophen(APAP),the most frequently used mild analgesic and antipyretic drug worldwide,is implicated in causing 46%of all acute liver failures in the USA and between 40%and 70%in *** predominant pharmacological intervention approved for mitigating such overdose is the antioxidant N-acetylcysteine(NAC);however,its efficacy is limited in cases of advanced liver injury or when administered at a late *** the current study,we discovered that treatment with a moderate intensity static magnetic field(SMF)notably reduced the mortality rate in mice subjected to high-dose APAP from 40%to 0%,proving effective at both the initial liver injury stage and the subsequent recovery *** the early phase of liver injury,SMF markedly reduced APAPinduced oxidative stress,free radicals,and liver damage,resulting in a reduction in multiple oxidative stress markers and an increase in the antioxidant glutathione(GSH).During the later stage of liver recovery,application of vertically downward SMF increased DNA synthesis and hepatocyte ***,the combination of NAC and SMF significantly mitigated liver damage induced by high-dose APAP and increased liver recovery,even 24 h post overdose,when the effectiveness of NAC alone substantially ***,this study provides a noninvasive non-pharmaceutical tool that offers dual benefits in the injury and repair stages following APAP *** note,this tool can work as an alternative to or in combination with NAC to prevent or minimize liver damage induced by APAP,and potentially other toxic overdoses.

关键词： Acetaminophen Acute liver injury Static magnetic fields Oxidative stress DNA synthesis

Optical PAM-4/PAM-8 generation via dual-Raman process in Rydberg atoms

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Chinese Physics B 2024年第6期33卷 383-388页

作者：宋晓云尹政任冠宇韩明志杨艾红祁义红彭延东 Qingdao Key Laboratory of terahertz Technology College of Electronic and Information EngineeringShandong University of Science and TechnologyQingdao 266590China School of Physics East China University of Science and TechnologyShanghai 200237China MIIT Key Laboratory of Complex-field Intelligent Exploration Beijing Institute of TechnologyBeijing 100081China

A scheme of optical four-level pulse amplitude modulation(PAM-4) is proposed based on dual-Raman process in Rydberg atoms. A probe field counter-propagates with a dual-Raman field which drives the ground and the excited states transition, respectively, and the Rydberg transition is driven by a microwave(MW) field. A gain peak appears in the probe transmission and is sensitive to the MW field strength. Optical PAM-4 can be achieved by encoding an MW signal and decoding the magnitude of a probe signal. Simulation results show that the differential nonlinearity and the integral nonlinearity of the proposed scheme can be reduced by 5 times and 6 times, respectively, compared with the counterparts of previous scheme, and the ratio of level separation mismatch is close to the ideal value 1. Moreover, the scheme is extended to optical PAM-8 signal, which may further improve the spectral efficiency.

关键词： Rydberg atoms PAM-4/PAM-8 dual-Raman process

GLOBAL BOUND ON THE GRADIENT OF SOLUTIONS TO p-LAPLACE TYPE EQUATIONS WITH MIXED DATA

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Acta Mathematica Scientia 2024年第4期44卷 1394-1414页

作者： Minh-Phuong TRAN The-Quang TRAN Thanh-Nhan NGUYEN Applied Analysis research group Faculty of Mathematics and StatisticsTon Duc Thang UniversityHo Chi Minh CityVietnam Nguyen Huu Huan high School Thu Duc CityVietnam group of Analysis and Applied Mathematics Department of MathematicsHo Chi Minh City University of EducationVietnam

In this paper,the study of gradient regularity for solutions of a class of elliptic problems of p-Laplace type is *** particular,we prove a global result concerning Lorentz-Morrey regularity of the non-homogeneous boundary data problem:-div((s^(2)+|▽u|^(2)p-2/2)▽u)=-div(|f|^(p-2)f)+g inΩ,u=h in■Ω,with the(sub-elliptic)degeneracy condition s∈[0,1]and with mixed data f∈L^(p)(Q;R^(n)),g∈Lp/(p-1)(Ω;R^(n))for p∈(1,n).This problem naturally arises in various applications such as dynamics of non-Newtonian fluid theory,electro-rheology,radiation of heat,plastic moulding and many *** on the idea of level-set inequality on fractional maximal distribution functions,it enables us to carry out a global regularity result of the solution via fractional maximal *** to the significance of M_(α)and its relation with Riesz potential,estimates via fractional maximal functions allow us to bound oscillations not only for solution but also its fractional derivatives of orderα.Our approach therefore has its own interest.

关键词： gradient estimates p-Laplace quasilinear elliptic equation fractional maximal operators Lorentz-Morrey spaces

Enhanced conductivity and weakened magnetism in Pb-doped Sr2IrO4

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Chinese Physics B 2024年第1期33卷 696-701页

作者：岳智来甄伟立牛瑞焦珂珂朱文卡皮雳张昌锦 high Magnetic field Laboratory Hefei Institutes of Physical ScienceChinese Academy of Sciences Science Island Branch of Graduate School University of Science and Technology of China Collaborative Innovation Center of Advanced Microstructures Nanjing University

group IV element Pb has been selected as the dopant to dope at the Sr site of Sr2IrO4. It is exciting to find that the single-phase crystal structure could be maintained with a high Pb doping level of up to x=0.3 in Sr2-xPbxIrO4. The mapping data obtained from energy-dispersive x-ray spectroscopy analyses give solid evidence that the Pb ions are uniformly distributed in the Sr2IrO4matrix. The incorporation of Pb leads to a moderate depression of the canted antiferromagnetic ordering state. The electrical conductivity could be greatly enhanced when the Pb doping content is higher than x=*** present results give a fresh material base to explore new physics in doped Sr2IrO4systems.

关键词： iridates doping conductivity magnetism

Synergic action of linear dispersion, second-order nonlinearity, and third-order nonlinearity in shaping the spectral profile of a femtosecond pulse transporting in a lithium niobate crystal

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Photonics research 2024年第4期12卷 774-783页

作者： LIHONG HONG YUANYUAN LIU ZHI-YUAN LI State Key Laboratory of high field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

We present a detailed theoretical and numerical analysis on the temporal-spectral-spatial evolution of a highpeak-power femtosecond laser pulse in two sets of systems:a pure lithium niobate(LN)plate and a periodically poled lithium niobate(PPLN)*** develop a modified unidimensional pulse propagation model that considers all the prominent linear and nonlinear processes and carried out the simulation process based on an improved split-step Fourier transformation *** theoretically analyze the synergic action of the linear dispersion effect,the second-order nonlinearity(2nd-NL)second-harmonic generation(SHG)effect,and the third-order nonlinearity(3rd-NL)self-phase modulation(SPM)effect,and clarify the physical mechanism underlying the peculiar and diverse spectral broadening patterns previously reported in LN and PPLN thin plate *** analysis and discussion provides a deeper insight into the synergetic contribution of these linear and nonlinear effects brought about by the interaction of a femtosecond laser pulse with the LN nonlinear crystal and helps to draw a picture to fully understand these fruitful optical physical processes,phenomena,and laws.

关键词： pulse nonlinearity lithium