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Magnetopause properties at the dusk magnetospheric flank from global magnetohydrodynamic simulations,the kinetic Vlasov equilibrium,and in situ observations--Potential implications for SMILE

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Earth and Planetary Physics 2024年第1期8卷 222-233页

作者： Marius Echim Costel Munteanu Gabriel Voitcu Eliza Teodorescu Institute of Space Science Măgurele 077125Romania Royal Belgian Institute for Space Aeronomy 1180 BrusselsBelgium solar-terrestrial Centre of Excellence(STCE) 1180 BrusselsBelgium

We derived the properties of the terrestrial magnetopause(MP)from two modeling approaches,one global–fluid,the other local–kinetic,and compared the results with data collected in situ by the Magnetospheric Multiscale 2(MMS2)*** used global magnetohydrodynamic(MHD)simulations of the Earth’s magnetosphere(publicly available from the NASA-CCMC[National Aeronautics and Space Administration–Community Coordinated Modeling center])and local Vlasov equilibrium models(based on kinetic models for tangential discontinuities)to extract spatial profiles of the plasma and field variables at the Earth’s *** global MHD simulations used initial solar wind conditions extracted from the OMNI database at the time epoch when the MMS2 observes the *** kinetic Vlasov model used asymptotic boundary conditions derived from the same in situ MMS measurements upstream or downstream of the *** global MHD simulations provide a three-dimensional image of the magnetosphere at the time when the MMS2 crosses the *** Vlasov model provides a one-dimensional local view of the MP derived from first principles of kinetic *** MMS2 experimental data also serve as a reference for comparing and validating the numerical simulations and *** found that the MP transition layer formed in global MHD simulations was generally localized closer to the Earth(roughly by one Earth radius)from the position of the real MP observed by the *** also found that the global MHD simulations overestimated the thickness of the MP transition by one order of magnitude for three analyzed variables:magnetic field,density,and tangential *** MP thickness derived from the local Vlasov equilibrium was consistent with observations for all three of these *** overestimation of density in the Vlasov equilibrium was reduced compared with the global MHD *** discuss our results in the context of future SMILE(solar wind Magnetosphere Ionosphere Link Explorer)campaigns for observing

关键词： magnetopause magnetohydrodynamic numerical simulations Vlasov equilibrium Magnetospheric Multiscale observations

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KRUPIN M.R.NURGALIEV A.R.NEMETS I.A.ZEMTSOV S.D.SUNTSOV T.B.MYALTON D.S.SERGEEV N.A.SOLOVEV D.V.SARYCHEV D.V.RYJAKOV S.N.TUGARINOV N.N.NAUMENKO National research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project center ITER” Moscow 123098Russia JSC“solar” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECRH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECRH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECRH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECRH regimes. Discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient R/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and R/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

Synthesis of boron nitride nanorod and its performance as a metalfree catalyst for oxidative desulfurization of diesel fuel

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Chinese Journal of Chemical Engineering 2024年第4期68卷 120-132页

作者： Tanaz Ghanadi Gholamreza Moradi Alimorad Rashidi Catalyst research center Faculty of Chemical and Petroleum EngineeringRazi UniversityKermanshahIran Nanotechnology research center Research Institute of Petroleum Industry(RIPI)TehranIran

In order to reduce the sulfur compounds in diesel fuel,boron nitride(BN)has been used as a novel metal-free catalyst in the present *** nanocatalyst was synthesized via template-free approach followed by heating treatment at 900℃ in nitrogen atmosphere that the characteristics of the sample were identified by the X-ray diffraction,Fourier-transform infrared spectroscopy,Raman spectroscopy,field emission scanning electron microscopy,transmission electron microscopy,atomic force microscopy,and N2 adsorption-desorption *** results of structural and morphological analysis represented that BN has been successfully *** efficacy of the main operating parameters on the process was studied by using response surface methodology based on the Box-Behnken design *** prepared catalyst showed high efficiency in oxidative desulfurization of diesel fuel with initial sulfur content of 8040 mg·kg^(-1)*** statistical analysis,a significant quadratic model was obtained to predict the sulfur removal as a function of efficient *** maximum efficiency of 72.4%was achieved under optimized conditions at oxidant/sulfur molar ratio of 10.2,temperature of 71℃,reaction time of 113 min,and catalyst dosage of 0.36 ***,the reusability of the BN was studied,and the result showed little reduction in activity of the catalyst after 10 times ***,a plausible mechanism was proposed for oxidation of sulfur compounds on the surface of the *** present study shows that BN materials can be selected as promising metal-free catalysts for desulfurization process.

关键词： Desulfurization Boron nitride(BN)nanostructure Experimental design BoxeBehnken

Design and synthesis of polyoxovanadate-based framework for efficient dye degradation

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Tungsten 2024年第2期6卷 447-453页

作者： Qing Lan Su-Juan Jin Zheng Wang Xu-Yang Li Yan Xiong Zhuo-Cheng Wang Shan-Shan Liu Zhi-Ming Zhang Qiang Zhao Engineering Technology research center of Henan Province for solar Catalysis School of Chemical and Pharmaceutical EngineeringNanyang Normal UniversityNanyang 473061China Institute of New Energy Materials&Low Carbon Technology Tianjin University of TechnologyTianjin 300384China

A new polyoxovanadate-based framework material[Cu(en)_(2)]_(4)V_(18)O_(42)(H_(2)O)·6H_(2)O(1)was designed and synthesized by hydrothermal reaction of NaVO_(3),Cu(NO_(3))_(2)·6H_(2)O and 1,2-diaminoethane(en)via carefully adjusting the pH value of the reaction *** structure of the title compound has been determined by single-crystal X-ray diff raction analysis,thermogravimetric analysis,infrared spectra and elemental *** structural analysis demonstrate the three-dimensional(3D)framework structure of compound 1,which was composed of the[V_(18)O_(42)(H_(2)O)]_(8)−({V_(18)O_(42)(H_(2)O)})anions linked by the Cu^(2+)*** 1 represents the fi rst 3D framework based on{V_(18)O_(42)(H_(2)O)}polyoxoanions and copper ***-driven degradation of residual organic pollutants in industrial wastewater is still a major problem for human *** experiments reveal that compound 1 possesses of excellent photocatalytic activity for the degradation of methylene blue and rhodamine B.

关键词： Polyoxovanadate Framework Polyoxovanadate-based framework Photocatalytic Organic pollutants

Promoted monolithic perovskite/organic tandem solar cells through elaborate manipulation of light transmission and carrier tunneling in interconnect junction

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Science China Chemistry 2024年

作者： Rongbo Wang Jiawei Zhang Juntao Zhao Ya Wang Yi Ding Ying Zhao Xiaodan Zhang Guofu Hou Institute of Photoelectronic Thin Film Devices and Technology Renewable Energy Conversion and Storage Center Solar Energy Conversion Center Nankai University Key Laboratory of Photoelectronic Thin Film Devices and Technology of Tianjin Engineering research center of Thin Film Photoelectronic Technology of Ministry of Education State Key Laboratory of Photovoltaic Materials and solar Cells Tianjin

Monolithic perovskite/organic tandem solar cells（TSCs） have emerged as promising thin film solar cells. It is recognized that interconnect junction plays a pivotal role in tandem devices. Consequently, wide bandgap Cs0.25FA0.75Pb(I0.6Br0.4)3perovskite top-cell and narrow bandgap PM6:Y6:PC61BM ternary organic bottom-cell were integrated in this study with several kinds of thin metal interconnect layers, which provides feasibility to elaborately manipulate light transmission and carrier tunneling process in interconnect junction. It is confirmed that, in comparison with Au, employing an Ag interconnect layer elevates integrated transmittance of light in longer wavelength regions, mainly because of the alleviated screening effect with a lower free electron concentration, which offers sufficient light harvest for the bottom-cell. Meanwhile, established energy barriers with moderate height afford convenient extraction and recombination for both holes and electrons. Hence, the performance of TSCs is promoted substantially. Moreover, an innovative Ag/Au double interconnect layer is proposed accordingly, which can preserve exceptional conductivity and light transmission and further reduce barrier height, especially for hole tunneling, by optimizing the band alignment between the interconnect layer and bottom-cell. Resultantly, the monolithic perovskite/organic TSC with a striking efficiency of 23.26% is achieved. In a word, this study can pave a general approach toward high-performance TSCs integration.

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Scientific objectives and payload configuration of the Chang'E-7 mission

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National Science Review 2024年第2期11卷 285-300页

作者： Chi Wang Yingzhuo Jia Changbin Xue Yangting Lin Jianzhong Liu Xiaohui Fu Lin Xu Yun Huang Yufen Zhao Yigang Xu Rui Gao Yong Wei Yuhua Tang Dengyun Yu Yongliao Zou China Aerospace Science and Technology Corporation State Key Laboratory of Space Weather National Space Science Center Chinese Academy of Sciences National Space Science center Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences Institute of Geochemistry Chinese Academy of Sciences Shandong Provincial Key Laboratory of Optical Astronomy and solar-terrestrial Environment School of Space Science and Physics Institute of Space SciencesShandong University Institute of Drug Discovery Technology Ningbo University State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences School of Earth Science and Engineering Sun Yat-sen University Lunar Exploration and Space Engineering center

As the cornerstone mission of the fourth phase of the Chinese Lunar Exploration Program, Chang'E-7(CE-7) was officially approved, and implementation started in 2022, including a main probe and a communication relay satellite. The main probe, consisting of an orbiter, a lander, a rover and a mini-flying probe, is scheduled to be launched in 2026. The lander will land on Shackleton crater's illuminated rim near the lunar south pole, along with the rover and mini-flying probe. The relay satellite(named Queqiao-2) will be launched in February 2024 as an independent mission to support relay communication during scientific exploration undertaken by Chang'E-4, the upcoming Chang'E-6 in 2024 and subsequent lunar *** CE-7 mission is mainly aimed at scientific and resource exploration of the lunar south pole. We present CE-7's scientific objectives, the scientific payloads configuration and the main functions for each scientific payload with its key technical specifications.

关键词： Chang’ E-7 scientific objectives scientific payloads

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel research center Research Institute of Highway Ministry of TransportBeijing 100088China Tunnel and Underground Engineering research center of Ministry of Education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service *** aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single *** used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track ***,the numerical method was verified by comparing the results of numerical simulation and on-site ***,the characteristics of aerodynamic pressure were ***,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was *** results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel *** addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel *** pressure amplitude in the two-train case is higher than that for a single *** maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage *** P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage *** P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Cognitive impairment in cerebral small vessel disease induced by hypertension

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Neural Regeneration research 2024年第7期19卷 1454-1462页

作者： Weipeng Wei Denglei Ma Lin Li Lan Zhang Department of Pharmacy Xuanwu Hospital of Capital Medical UniversityBeijingChina Beijing Geriatric Medical research center Beijing Engineering Research Center for Nervous System DrugsNational Center for Neurological DisordersNational Clinical Research Center for Geriatric DiseasesBeijingChina

Hypertension is a primary risk factor for the progression of cognitive impairment caused by cerebral small vessel disease,the most common cerebrovascular *** r,the causal relationship between hypertension and cerebral small vessel disease remains *** has substantial negative impacts on brain health and is recognized as a risk factor for cerebrovascular *** hypertension and lifestyle factors are associated with risks for stro ke and dementia,and cerebral small vessel disease can cause dementia and *** is the main driver of cerebral small vessel disease,which changes the structure and function of cerebral vessels via various mechanisms and leads to lacunar infarction,leukoaraiosis,white matter lesions,and intracerebral hemorrhage,ultimately res ulting in cognitive decline and demonstrating that the brain is the to rget organ of *** review updates our understanding of the pathogenesis of hypertensioninduced cerebral small vessel disease and the res ulting changes in brain structure and function and declines in cognitive *** also discuss drugs to treat cerebral small vessel disease and cognitive impairment.

关键词： blood-brain barrier cerebral small vessel disease cognitive impairment dementia endothelial dysfunction enlarged perivascular space hypertension lacunar infarction neuroinflammation treatment white matter high signal intensity

Design of Resilient Sensor Networks Balancing Resilience and Efficiency

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International Journal of Disaster Risk Science 2024年第1期15卷 107-115页

作者： Sergey N.Vecherin Kiril D.Ratmanski Luke Hogewood Igor Linkov Cold Regions research and Engineering Laboratory Engineering Research and Development CenterHanoverNH 03755USA Environmental Laboratory Engineering Research and Development CenterVicksburgMS 39180USA

In recent years,the notion of resilience has been developed and applied in many technical areas,becoming exceptionally pertinent to disaster risk *** a disaster situation,accurate sensing information is the key to efficient recovery *** general,resilience aims to minimize the impact of disruptions to systems through the fast recovery of critical functionality,but resilient design may require redundancy and could increase *** this article,we describe a method based on binary linear programming for sensor network design balancing efficiency with *** application of the developed framework is demonstrated for the case of interior building surveillance utilizing infrared sensors in both twoand three-dimensional *** method provides optimal sensor placement,taking into account critical functionality and a desired level of resilience and considering sensor type and *** problem formulation,resilience requirements,and application of the optimization algorithm are described in *** of sensor locations with and without resilience requirements shows that resilient configuration requires redundancy in number of sensors and their intelligent *** tasks are successfully solved by the described method,which can be applied to strengthen the resilience of sensor networks by *** proposed methodology is suitable for large-scale optimization problems with many sensors and extensive coverage areas.

关键词： Binary linear programming Optimal sensor placement Redundant networks Resilience and efciency Resilient sensor networks