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紫金山天文台台刊 1996年第3期15卷 12-19页

作者： W.K.H Schmidt max-planck-institut fur Aeronomie 37191 katl enburg- LindauGermany

A short review of the Assessment Study results of a Mercury Obriter mission which ws propoesd to ESA in 1993 is given.

关键词：侧切肠面吐血加成比压旧址田令幻山

Many faces of neuronal activity manipulation in Drosophila

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Neural Regeneration Research 2025年第9期20卷 2574-2576页

作者： Amber Krebs Steffen Kautzmann Christian Klämbt institut für Neuro-und Verhaltensbiologie MünsterGermany

Animals exhibit complex responses to external and internal *** information is computed by interconnected neurons that express numerous ion channels,which modulate the neuronal membrane *** can neuronal activity orchestrate complex motor patterns or allow learning from previous experience?To answer such questions,we need the ability not only to record,but also to modulate neuronal activity in both space(e.g.,neuronal subsets)and time.

关键词： manipulation potential. neuronal

CWA Formalizations in Multi-Valued Logics

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Journal of Computer Science & Technology 2001年第3期16卷 263-269页

作者：吴尽昭 max-planck-institut für Informatik Saarbrücken Germany

To enhance the expressive power and the declarative ability of a deductive database, various CWA (Closed World Assumption) formalizations including the naive CWA, the generalized CWA and the careful CWA are extended to multi-valued logics. The basic idea is to embed logic formulas into some polynomial ring. The extensions can be applied in a uniform manner to any finitely multi-valued logics. Therefore they are also of computational significance.

关键词： CWA formalization multi-valued logic polynomial form query evaluation

Mode structure symmetry breaking of reversed shear Alfvén eigenmodes and its impact on the generation of parallel velocity asymmetries in energetic particle distribution

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Plasma Science and Technology 2022年第2期24卷 17-27页

作者： Guo MENG Philipp LAUBER Xin WANG Zhixin LU max-planck-institut fiir Plasmaphysik D-85748 GarchingGermany

In this work,the gyrokinetic eigenvalue code LIGKA,the drift-kinetic/MHD hybrid code HMGC and the gyrokinetic full-f code TRIMEG-GKX are employed to study the mode structure details of reversed shear Alfvén eigenmodes(RSAEs).Using the parameters from an ASDEXUpgrade plasma,a benchmark with the three different physical models for RSAE without and with energetic particles(EPs)is carried *** agreement has been found for the mode frequency and the growth *** structure symmetry breaking(MSSB)is observed when EPs are included,due to the EPs’non-perturbative *** is found that the MSSB properties are featured by a finite radial wave phase velocity,and the linear mode structure can be well described by an analytical complex Gaussian expressionФ(s)=e^(-σ(s-s_(0))^(2))with complex parametersσand s_(0),where s is the normalized radial *** mode structure is distorted in opposite manners when the EP drive shifted from one side of qminto the other side,and specifically,a non-zero average radial wave number with opposite signs is *** initial EP density profiles and the corresponding mode structures have been used as the input of HAGIS code to study the EP *** parallel velocity of EPs is generated in opposite directions,due to different values of the average radial wave number,corresponding to different initial EP density profiles with EP drive shifted away from the qmin.

关键词： reversed shear Alfvén eigenmode symmetry breaking energetic particles non-perturbative effects

Stable and Unstable Eigensolutions of Laplace's Tidal Equations for Zonal Wavenumber Zero

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Advances in Atmospheric Sciences 1993年第1期10卷 21-40页

作者： RolfMüller max-planck-institut fur Chemie Abt. Luftchemie Postfach 3060 D-6500 Mainz FRG

Laplace's tidal equations are of great importance in various fields of geophysics. Here, the special case of zonal symmetry (zonal wavenumber m = 0) is investigated, where degenerate sets of eigensolutions appear. New results are presented for the inclusion of dissipative processes and the case of unstable conditions. In both instances the (nonzero) eigenfrequencies are complex. In the latter case, additional stable (i.e. real) eigenfrequencies appear in the numerical results for the absolute value of the Lambparameter ε being larger than a critical value εc. further, it is shown that any degeneracies are removed through the inclusion of dissipation. Moreover, asymptotic relations are derived employing the relation of Laplace's tidal equations for m = 0 to the spheroidal differential equation. The implications of these findings to numerical techniques are demonstrated and results of computations are presented.

关键词： Stable and Unstable Eigensolutions of Laplace’s Tidal Equations for Zonal Wavenumber Zero Zn

Progress of research on AGNs at the Urumqi Observatory

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Science China(Physics,Mechanics & Astronomy) 2010年第S1期53卷 244-246页

作者： T.P.KRICHBAUM L.FUHRMANN N.MARCHILI max-planck-institut fur Radioastronomie Auf dem Hugel 6953121 BonnGermany

We report the progress on Very Long Baseline Interferometry(VLBI) observations of Gigahertz Peaked Spectrum(GPS) radio sources,and single-dish observations of active galactic nuclei(AGNs).The GPS sources are a kind of young AGNs observable in *** our VLBI observations at 1.6 and 5 GHz with the European VLBI Network(EVN) including the Urumqi and Shanghai stations,most GPS sources show compact doubles with sizes less than 1 *** have classified the sources into double-lobes,core-jets,and complex structures according to the spectral indices as well as *** also estimated the values of the jet viewing angle for the symmetric *** addition,we are monitoring a few samples of AGNs with the Urumqi 25-meter radio telescope,in order to find flux *** detected rapid flux variability in quasar 1156+295,and relatively slow variability in a few of the *** origin of the rapid variability is ***,we launched a radio-optical monitoring program called Fermi-AGN in 2009.

关键词： active galactic nuclei VLBI intra-day variability

On the character of certain tilting modules

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Science China Mathematics 2018年第2期61卷 295-298页

作者： George Lusztig Geordie Williamson Department of Mathematics Massachusetts Institute of Technology Cambridge MA 02139-4307 USA max planck institut fur Mathematik Bonn 53111 Germany

Let G be a semisimple group over an algebraically closed field of characteristic p > 0. We give a(partly conjectural) closed formula for the character of many indecomposable tilting rational G-modules assuming that p ... 详细信息

关键词： semisimple group tilting module character formula

Models and observations of sunspot penumbrae

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Science China(Physics,Mechanics & Astronomy) 2009年第11期52卷 1670-1677页

作者： BORRERO Juan Manuel max planck institut fr Sonnensystemforschung Max Planck Strasse 2 D 37191 Katlenburg-Lindau Germany

The mysteries of sunspot penumbrae have been under an intense scrutiny for the past 10 years. During this time, some models have been proposed and refuted, while the surviving ones had to be modified, adapted and evolved to explain the ever-increasing array of observational constraints. In this contribution I will review two of the present models, emphasizing their contributions to this field, but also pinpointing some of their inadequacies to explain a number of recent observations at very high spatial resolution (0.32 ). To help explaining these new observations I propose some modifications to each of those models. These modifications bring those two seemingly opposite models closer together into a general picture that agrees well with recent 3D magneto-hydrodynamic simulations.

关键词： sunspots magnetic fields spectropolarimetry magnetohydrodynamics

Search for H I emission from superdisk candidates associated with radio galaxies

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Research in Astronomy and Astrophysics 2019年第6期19卷 71-78页

作者： Abhijeet Anand Nirupam Roy Gopal-Krishna max-planck-institut fur Astrophysik Karl-Schwarzschild-Str. 1 D-85741 Garching Germany Department of Physics Indian Institute of Science Bangalore - 560012 India Aryabhatta Research institute of Observational Sciences (ARIES) Manora Peak Nainital - 263129 India max-planck-institut fur Radioastronomie Auf dem Hugel 69 53121 Bonn Germany

Giant gaseous layers(termed “superdisks”) have been hypothesized in the past to account for the strip-like radio emission gap(or straight-edged central brightness depression) observed between twin radio lobes, in over a dozen relatively nearby powerful Fanaroff-Riley Class II radio galaxies. They could also provide a plausible alternative explanation for a range of observations. Although a number of explanations have been proposed for the origin of the superdisks, little is known about their material content. Some X-ray observations of superdisk candidates indicate the presence of hot gas, but a cool dusty medium also seems to be common. If they are entirely or partly composed of neutral gas, then it may be directly detectable and we report here a first attempt to detect/image any neutral hydrogen gas present in the superdisks that are inferred to be present in four nearby radio galaxies. We have not found a positive H I signal in any of the four sources, resulting in tight upper limits on the H I number density in the postulated superdisks,estimated directly from the central rms noise values of the final radio continuum subtracted image. The estimated ranges of the upper limit on neutral hydrogen number density and column density are 10^-4-10^-3 atoms per cm3 and 10^19-10^20 atoms per cm^2, respectively. No positive H I signal is detected even after combining all the four available H I images(with inverse variance weighting). This clearly rules out an H I dominated superdisk as a viable model to explain these structures, however, the possibility of a superdisk being composed of warm/hot gas still remains open.

关键词： galaxies:active galaxies:general galaxies:structure radio lines:galaxies

Mechanical Properties of Single-Walled （5,5） Carbon Nanotubes with Vacancy Defects

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Chinese Physics Letters 2007年第7期24卷 2036-2039页

作者：袁士俊孔勇李发伸 Key Lab on Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University Lanzhou 730000 max-planck-institut fur Metallforschung Heisenbergstrasse 3 70569 Stuttgart Germany

First-principles simulation is used to investigate the structural and mechanical properties of vacancy defective single-walled （5,5） carbon nanotubes. The relations of the defect concentration, distribution and characteristic of defects to Young＇s modulus of nanotubes are quantitatively studied. It is found that each dangling-bond structure （per supercell） decreases Young＇s modulus of nanotube by 6.1% for symmetrical distribution cases. However the concentrative vacancy structure with saturated atoms has less influence on carbon nanotubes. It is suggested that the mechanical properties of carbon nanotubes depend strongly upon the structure and relative position of vacancies in a certain defect concentration.

关键词： Mechanical Properties Single-Walled