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The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa W.R.dunn A.Foster F.S.Porter d.G.Sibeck B.Walsh The Henry A.Rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATmOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SmILE’s(Solar wind magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission mapper(LEm),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEm will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SmILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Enhanced quantum resources via two distant atom-cavity systems under the influence of atomic dissipation

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Communications in Theoretical Physics 2024年第2期76卷 62-73页

作者： m Setodeh Kheirabady m K Tavassoly m Rafeie E Ghasemian Laser and Optics Group Faculty of PhysicsYazd UniversityYazd 89195-741Iran department of Electrical Engineering Faculty of Intelligent Systems Engineering and Data SciencePersian Gulf UniversityBushehrIran

Quantum resources such as entanglement and coherence are the holy grail for modern quantum technologies. Although the unwanted environmental effects tackle quantum information processing tasks, suprisingly these key quantum resources may be protected and even enhanced by the implementation of some special hybrid open quantum systems. Here, we aim to show how a dissipative atom-cavity-system can be accomplished to generate enhanced quantum *** do so, we consider a couple of dissipative cavities, where each one contains two effective two-level atoms interacting with a single-mode cavity field. In practical applications, a classical laser field may be applied to drive each atomic subsystem. After driving the system, a Bell-state measurement is performed on the output of the system to quantify the entanglement and coherence. The obtained results reveal that the remote entanglement and coherence between the atoms existing inside the two distant cavities are not only enhanced, but can be stabilized, even under the action of dissipation. In contrast, the local entanglement between two atoms inside each dissipative cavity attenuates due to the presence of unwanted environmental ***, the local coherence may show the same behavior as the remote ***, the system provides the steady state entanglement in various interaction regimes,particularly in the strong atom-cavity coupling and with relatively large detuning. more interestingly, our numerical analyses demonstrate that the system may show a memory effect due to the fact that the death and revival of the entanglement take place during the interaction. Our proposed model may find potential applications for the implementation of long distance quantum networks. In particular, it facilitates the distribution of quantum resources between the nodes of large-scale quantum networks for secure communication.

关键词： remote entanglement and coherence atomic dissipation steady state entanglement Bell-statemeasurement

Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

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Applied mathematics and mechanics(English Edition) 2024年第2期45卷 373-388页

作者： m.RAHmAN m.TURKYILmAZOGLU Z.mUSHTAQ department of mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan department of mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(PdEs))are transformed to the nonlinear ordinary differential equations(OdEs)with the help of similarity *** system of equations takes the form of OdEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c mATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are Pr=6.2,Re=2,m=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Reflection sensitivity of dual-state quantum dot lasers

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Photonics Research 2023年第10期11卷 1713-1722页

作者： ZHIYONG JIN HEmING HUANG YUEGUANG ZHOU SHIYUAN ZHAO SHIHAO dING CHENG WANG YONG YAO XIAOCHUAN XU frÉdÉric GRILLOT JIANAN dUAN State Key Laboratory on Tunable Laser Technology School of Electronic and Information EngineeringHarbin Institute of TechnologyShenzhen 518055China LTCI Telecom ParisInstitut Polytechnique de Paris91120 PalaiseauFrance dTU Electro Department of Electrical and Photonics EngineeringTechnical University of Denmark2800 LyngbyDenmark School of Information Science and Technology ShanghaiTech UniversityShanghai 201210China Center for High Technology materials The University of New-MexicoAlbuquerqueNew Mexico 87106USA

This work experimentally and theoretically demonstrates the effect of excited state lasing on the reflection sensitivity of dual-state quantum dot lasers,showing that the laser exhibits higher sensitivity to external optical feedback when reaching the excited state lasing *** sensitivity can be degraded by increasing the excited-to-ground-state energy separation,which results in a high excited-to-ground-state threshold *** addition,the occurrence of excited state lasing decreases the damping factor and increases the linewidth enhancement factor,which leads to a low critical feedback *** findings illuminate a path to fabricate reflectioninsensitive quantum dot lasers for isolator-free photonic integrated circuits.

关键词： state excited quantum

Quaternionic monge–Ampère measure on Pluripolar Set

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Acta mathematica Sinica,English Series 2024年第6期40卷 1431-1457页

作者： Hichame AmAL Saïd ASSERdA Fadoua BOUKHARI department of mathematics Laboratory LaREAMIRegional Centre of Trades of Education and TrainingKenitraMorocco Ibn Tofail University Faculty of SciencesDepartment of MathematicsPO 242 KenitraMorroco

In this paper, we prove that in a hyperconvex domain Ω in H^(n), if a non-negative Borel measure is dominated by a quaternionic monge–Ampère measure, then it is a quaternionic monge–Ampère measure of a function i... 详细信息

关键词： Quaternion space monge-Amp`ere operator plurisubharmonic function

microscale shaping and rounding of ridge arrays and star pattern features on nickel mould via electrochemical polishing

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Advances in manufacturing 2024年第2期12卷 207-226页

作者： Sana Zaki Nan Zhang michael d.Gilchrist School of mechanical and materials Engineering University College DublinBelfieldDublin 4Ireland

High quality micro mould tools are critical for ensuring defect-free production of micro injection moulded *** demoulding stage of the micro injection moulding can adversely affect the surface integrity due to friction,adhesion and thermal stresses between the metallic mould and polymeric replicated *** the present work,we propose the use of precision electropolishing(EP)as a shaping and polishing process to control the draft angle and fillet radius of micro features in order to ease *** defects that occur in replicated polymer parts include cracks,burrs and distorted features.A nickel mould having multiple linear ridges and star shape patterns was designed for the present investigation to have characteristic dimensions ranging from 10μm to 150μm and with various aspect ratios to study the effect of electropolishing on modifying the shape of micro features and surface morphology.A transient 2d computational analysis has been conducted to anticipate the effect of shaping on the Ni mould after electrochemical polishing with non-uniform material removal rates,based on the distribution of current *** experimental results indicate that after shaping using EP,the draft angle of star-patterns and linear patterns can be effectively increased by approximately 3.6°,while the fillet radius increases by up to 5.0μ*** controlling the electropolishing process,the surface roughness can be maintained under 50 *** work uses a green and environmental friendly nickel sulfamate electrolyte which can be effective for shaping of nickel micro features without causing any surface deposition.

关键词： micro feature shaping and electropolishing micro mould tools Green electrolyte demoulding micro patterns

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied mathematics and mechanics(English Edition) 2024年第5期45卷 819-836页

作者： d.LEE S.CHANG J.LEE department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea department of mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPCE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPCE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPCE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPCE) static reanalysis method static condensation substructuring

dNP NmR reveals the hidden surface C–C bond growth mechanism over ZnAlO_(x) during syngas conversion

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Journal of Energy Chemistry 2022年第4期31卷 640-644页

作者： Pan Gao dong Xiao Zhenchao Zhao Subhradip Paul frédéric Blanc Xiuwen Han Guangjin Hou Xinhe Bao State Key Laboratory of Catalysis National Laboratory for Clean Energy2011-Collaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of Sciences457 Zhongshan RoadDalian 116023LiaoningChina dNP mAS NmR Facility Sir Peter Mansfield Imaging CentreUniversity of NottinghamNottingham NG72RDUnited Kingdom department of Chemistry University of LiverpoolCrown StreetLiverpool L697ZDUnited Kingdom Stephenson Institute for Renewable Energy University of LiverpoolCrown StreetLiverpool L697ZDUnited Kingdom

direct catalytic transformation of syngas(CO/H_(2)) into high value-added hydrocarbons has been one of the most attractive,yet challenging issues in C1 chemistry. In recent years, the concept of oxide-zeolite(OXZEO) bifunctional catalysis has emerged and spurred renewed enthusiasm in this field [1,2]. This method describes the use of selected oxide-zeolite-based composite catalysts for the direct syngas-to-hydrocarbons conversion.

关键词： zeolite hydrocarbons syngas

Assessment of the Level of Knowledge about Chronic Renal Failure in 271 Hypertensive Patients in Brazzaville

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Open Journal of Nephrology 2024年第1期14卷 25-36页

作者： daniel Tony Eyeni Sinomono Ange Niama Gaël Honal mahoungou Éric Gandzali-Ngabé Ndinga Berline Ngoma Precieux dalia mboungo richard Loumingo department of Nephrology University Hospital Center Faculty of Health Sciences Marien Ngouabi University Brazzaville Congo department of Public Health Faculty of Health Sciences Marien Ngouabi University Brazzaville Congo

Background and Objectives: Chronic kidney disease (CKd) is now a global public health problem. In low- and middle-income countries such as the Congo, access to dialysis is low and inequitable. The prevention of CKd involves raising awareness among patients at risk, such as those suffering from arterial hypertension (AH), by improving their knowledge of CKd. The objectives of our work were to determine the level of knowledge about CKd among hypertensive patients and to identify the factors associated with a low level of knowledge. methodology: We conducted a 3-month descriptive and analytical cross-sectional study from 1 August to 30 October 2023 in 3 large public hospitals in Brazzaville (capital of the Republic of Congo). We included: hypertensive patients aged 18 and over who had freely consented to participate in our study and were able to answer the questions on the survey form. Patients with known hypertension who had been followed for less than 3 years and those with known chronic renal failure were not included. Results: The mean age was 58.4 ± 14.4 years (29 - 88 years). There were 121 men and 150 women (sex ratio = 0.8). All the patients were educated;37.2% with a higher level of education and 13.6% with primary education. 24 patients (9%) had a good level of knowledge about CKd and 153 (56%) had poor knowledge. A good level of knowledge was associated with the duration of hypertension, intellectual level and the existence of associated heart disease. Conclusion: Our study reveals a significant lack of knowledge about chronic kidney disease among hypertensive patients in Brazzaville.

关键词： Knowledge Chronic Renal Failure Hypertensives Brazzaville