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排序方式: 共有249条查询结果,搜索用时 15 毫秒
61.
M. J. Lehner C. Alcock T. Axelrod F. Bianco Y.‐I. Byun W.‐P. Chen K. H. Cook R. Dave I. de Pater J. Giammarco S.‐K. King T. Lee J. Lissauer S. L. Marshall S. Mondal T. Nihei J. Rice M. Schwamb A. Wang S.‐Y. Wang C.‐Y. Wen Z.‐W. Zhang 《Astronomische Nachrichten》2006,327(8):814-817
The Taiwanese‐American Occultation Survey (TAOS) seeks to determine the number and size spectrum for small (∼3 km) bodies in the Kuiper Belt. This will be accomplished by searching for the brief occultations of bright stars (R ∼ 14) by these objects. We have designed and built a special purpose photometric monitoring system for this purpose. TAOS comprises four 50 cm telescopes, each equipped with a 2048 × 2048 pixel CCD camera, in a compact array located in the central highlands of Taiwan. TAOS will monitor up to 2 000 stars at 5 Hz. The system went into scientific operation in the autumn of 2005. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
62.
Christian Theis Werner Zeilinger Susanne Hüttemeister 《Astronomische Nachrichten》2005,326(7):485-521
Posters: Because of the large number of contributions, some oral presentations had to be transferred into Posters. The reader is referred to the final programme for the actual allocation of Posters. A01 Chemical Enrichment of the Intracluster Medium A02 Structural analysis of high‐velocity clouds – Evidence for an interaction between the Milky Way and the Magellanic System A03 Multi‐Phase Chemo‐Dynamical SPH code for galaxy evolution A04 The proper motion of M33 A05 Wavelet analysis of Intra–group Light in Hickson Compact Groups A06 Evidence for an evolutionary connection between early and late type dwarf galaxies A07 Dwarf Galaxies in the NGC 5846 Group A08 X‐ray spectroscopy of serendipitous clusters of galaxies in XMM‐Newton observations A09 Evolution of smale scale systems of galaxies: X‐ray detected E+S galaxy pairs A10 Modelling Star Formation in Interacting Galaxies A11 NGC 1427A – the beginning of the end: a lonely dwarf irregular entering the dense core of the Fornax cluster A12 Dwarf galaxies in galaxy groups: Photo‐evaporation, orbits and gas stripping A13 High resolution stellar kinematics for the central component of the Polar Ring Galaxy NGC 4650A A14 The Influence of Environment on the Morphological Evolution of Disk‐Dominated Galaxies A15 Interactions and star formation in galaxies A16 Dust Condensations and Molecular Clouds in Interacting Spirals A17 Star formation rates and kinematics of modelled interacting galaxies A18 Evolution of Galaxies and the Tully–Fisher Relation A19 Evolution and Collision of Galaxies on the GRID A20 Multiwavelength observations of two S+E merger candidates: the Medusa and NGC 4441 A21 Interacting Galaxies in Small Galaxy Groups A22 Virial and total masses of galaxy triplets in the Local Supercluster A23 Simulations of Interaction Processes of Galaxies with the Intra‐Cluster Medium A24 Chemical evolution of the thick and thin disks of our Galaxy A25 Dust properties of UV‐bright galaxies at z ∼ 2 A26 Simulation of the Gravitational Collapse and Fragmentation of Rotating Molecular Clouds A27 NGC 5719/13: interacting spirals forming a counter‐rotating stellar disc A28 Starbursts in very metal‐poor dwarfs due to interactions and mergers: link to the processes in the high‐redshift young galaxies A29 Testing galaxy evolution in the field: morphology and properties of the diffuse X‐ray emission in shell galaxies A30 Effects of galactic winds on dIrrs with particular emphasis on NGC 1569 and the refill of superbubble cavities A31 Galaxy formation through merging at z ≈ 2 A32 3D simulations of the ISM‐ICM interaction of disk galaxies in clusters A33 Gas replenishment in ram pressure stripped disk galaxies A34 New Results on the Kinematics of the Outer Cluster System of NGC 1399 A35 Chemical gradient evolution in massive galaxy disk due to its minor merger with dwarf galaxy A36 The complex kinematics of galaxies in Hickson 62 A37 Dust in the outer regions of interacting galaxies A38 Dynamical interaction of M31 and M32 A39 A comparative study of galaxy properties in low‐ and high density environment A40 Compact Groups in Dense Environment: The Case of IC1370 A41 The Star Formation History of CG J1720‐67.8 A42 Galaxy populations in the infall regions of intermediate redshift clusters A43 The study of gravitational fragmentation in two‐clumps collisions A44 Star Formation Activity in Galaxy Clusters Near and Far A45 An Exploration of the Merging History of the Local Starburst Galaxy, NGC 3310 A46 The high‐velocity clouds of M31: tracers of galactic evolution A47 The Properties of Fossil Groups 相似文献
63.
Andrew Curtis Jayakrishnan Ajayakumar Eric Jefferis Susanne Mitchell 《International journal of geographical information science》2019,33(6):1224-1250
ABSTRACTThe importance of including a contextual underpinning to the spatial analysis of social data is gaining traction in the spatial science community. The challenge, though, is how to capture these data in a rigorous manner that is translational. One method that has shown promise in achieving this aim is the spatial video geonarrative (SVG), and in this paper we pose questions that advance the science of geonarratives through a case study of criminal ex-offenders. Eleven ex-offenders provided sketch maps and SVGs identifying high-crime areas of their community. Wordmapper software was used to map and classify the SVG content; its spatial filter extension was used for hot spot mapping with statistical significance tested using Monte Carlo simulations. Then, each subject’s sketch map and SVG were compared. Results reveal that SVGs consistently produce finer spatial-scale data and more locations of relevance than the sketch maps. SVGs also provide explanation of spatial-temporal processes and causal mechanisms linked to specific places, which are not evident in the sketch maps. SVG can be a rigorous translational method for collecting data on the geographic context of many phenomena. Therefore, this paper makes an important advance in understanding how environmentally immersive methods contribute to the understanding of geographic context. 相似文献
64.
Porous,S‐bearing silica in metal‐sulfide nodules and in the interchondrule clastic matrix in two EH3 chondrites
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S. W. Lehner P. Németh M. I. Petaev P. R. Buseck 《Meteoritics & planetary science》2017,52(11):2424-2436
Two new occurrences of porous, S‐bearing, amorphous silica are described within metal‐sulfide nodules (MSN) and as interchondrule patches in EH3 chondrites SAH 97072 and ALH 84170. This porous amorphous material, which was first reported from sulfide‐bearing chondrules, consists of sinewy SiO2‐rich areas containing S with minor Na or Ca as well as Fe, Mg, and Al. Some pores contain minerals including pyrite, pyrrhotite, and anhydrite. Most pores appear vacant or contain unidentified material that is unstable under analytical conditions. Niningerite, olivine, enstatite, albite, and kumdykolite occur enclosed within porous silica patches. Porous silica is commonly interfingered with cristobalite suggesting its amorphous structure resulted from high‐temperature quenching. We interpret the S‐bearing porous silica to be a product of silicate sulfidation, and the Na, Ca, Fe, Mg, and Al detectable within this material are chemical residues of sulfidized silicates and metal. The occurrence of porous silica in the cores of MSN, which are considered to be pre‐accretionary objects, suggests the sulfidizing conditions occurred prior to final parent‐body solidification. Ubiquitous S‐bearing porous silica among sulfide‐bearing chondrules, MSN, and in the interchondrule clastic matrix, suggests that similar sulfidizing conditions affected all the constituents of these EH3 chondrites. 相似文献
65.
Susanne Aalto 《Astrophysics and Space Science》2005,295(1-2):143-153
The molecular phase of the ISM constitutes the main source of fuel for the activity in starburst and AGNs. The physical conditions and chemical constitution of the molecular gas will change with, and respond to, the evolution of the activity. This paper includes a short discussion of the 12CO/13CO 1–0 line intensity ratio as a diagnostic tool of the molecular gas properties of luminous galaxies – paired with examples of high-resolution studies of how the line ratio varies within galaxies. A possible connection between the OH megamasers and galaxies with unusually high 12CO/13CO 1–0 line intensity ratios are also briefly discussed.The relative intensities of the dense gas tracers HNC, HCN, HCO+ and CN are a result of both chemistry and starburst evolution. The discussion on the interpretation of HNC 1–0 emission includes the importance of ion-neutral chemistry in a luminous starburst region. Finally, simple cartoon ISM models and how they can be applied to LIRGs and ULIRGs, are presented. 相似文献
66.
David Schmidt Susanne T. Schmidt Joseph Mullis Rafael Ferreiro Mählmann Martin Frey 《Contributions to Mineralogy and Petrology》1997,129(4):385-403
The andesitic early Oligocene Taveyanne metagreywacke of the Helvetic nappes of western Switzerland shows an increase of
metamorphic grade from zeolite facies through lower greenschist facies. Electron microprobe analysis, fluid inclusion thermometry,
stable isotope analysis, coal rank, illite and chlorite crystallinity and thermodynamic calculations were carried out to determine
metamorphic conditions. Evaluation of all techniques used in this study suggest that only combinations of different parameters
yield reliable information to constrain very low-grade metamorphic conditions. Electron microprobe analyses are presented
for actinolite, chlorite, epidote, phengite, laumontite, prehnite, pumpellyite, and titanite. With increasing metamorphic
grade, chlorite is enriched in tetrahedral Al, pumpellyite becomes poorer in Fetot and more homogeneous in chemical composition, and titanite tends to incorporate Ti at the expense of Al and Fe3+. Metamorphic P-T conditions were determined by a combination of fluid inclusion microthermobarometry, stable isotope thermometry on quartz-calcite
veins, chlorite “geothermometry” and thermodynamic calculations. Peak temperatures range from 210–250 °C for zeolite facies
to 270–300 °C for prehnite-pumpellyite facies to 300–360 °C for pumpellyite-actinolite facies. An evaluation of 289 chlorite
analyses indicates that the tetrahedral Al content is negatively correlated with the saponite component. Temperatures derived
from chlorite “geothermometry” match maximum temperature conditions mentioned above. Illite crystallinity data for shales
and slates intercalated with the Taveyanne metagreywacke indicate that the diagenetic zone correlates with the zeolite facies,
the upper anchizone with the prehnite-pumpellyite facies, and the lower epizone with the pumpellyite-actinolite facies. A
comparison of coal rank and illite crystallinity data (n=12,r=0.91) yielded R
max values of 2.9 and 5.5% for the lower and upper boundary of the anchizone, respectively.
Received: 2 August 1996 / Accepted: 16 July 1997 相似文献
67.
This article addresses the importance and meanings of formal and informal social support relationships and neighbourhood ties for older adults ‘ageing in place’ in urban neighbourhoods in two different welfare state settings: Portland (Oregon, the United States) and Amsterdam (the Netherlands). The rising number of people growing old(er) in urban environments raises new demands and pressing challenges for urban development. The majority of older adults are and will be ageing in their homes and communities, as opposed to institutionalized care facilities and settings. At the same time, the provision of formal and public care is being increasingly challenged by government cutbacks. On top of this, the formerly strong welfare states in many European countries have weakened. In-depth interviews with 40 older adults and key informants in two neighbourhoods in each city provide the empirical basis for this study. In Portland, there are widespread local civic initiatives related to care provision for older adults. The city has a long tradition both of individual responsibility and community culture, which has emerged from and appears to compensate for the overall lack of state services and support. Amsterdam has a long tradition of state provision, but is experiencing a policy shift towards a stronger reliance on private market-led services, and an emphasis on family and community as providers of support. Although a few emerging local initiatives for elderly care in Amsterdam were identified, it is unclear whether this form of community support can compensate for decreasing state provision in Amsterdam. This study raises concerns about the future of care provision for older adults living in unsupportive urban neighbourhoods, without financial resources or nearby relatives. 相似文献
68.
69.
70.
Differential recruitment of introduced Pacific oysters and native mussels at the North Sea coast: coexistence possible? 总被引:5,自引:3,他引:5
Susanne Diederich 《Journal of Sea Research》2005,53(4):269-281
Pacific oysters (Crassostrea gigas Thunberg 1793) have been introduced into the Wadden Sea (North Sea), where they settle on native mussel beds (Mytilus edulis L.), which represent the only extensive insular hard substrata in this soft-sediment environment. As abundances of C. gigas rose, some mussel beds became increasingly overgrown with oysters, whereas others did not. Field experiments revealed that recruitment of C. gigas was higher in the lower intertidal than in the upper subtidal zone, that it was higher on conspecifics than on mussels, and that it was not affected by barnacle epigrowth except when settling on mussels. Mussel recruitment is known from inter- and subtidal zones. It occurred equally on oyster and mussel shells but showed a clear preference for barnacle epigrowth over clean shells. Assuming that settlement and recruitment are key processes for species abundances on the North Sea coast, it is predicted that the positive feedback in oyster settlement will lead to rapid reef formation of this invader at the expense of mussel beds. Mussels, however, may escape competitive exclusion by settling between or on the larger oysters especially when barnacles are abundant. Experimental patches with mussels were more often covered by fucoid algae (Fucus vesiculosus forma mytili Nienburg) than patches with oysters, and oyster recruitment was poor underneath such algal canopies. Thus, fucoids may provide the native mussels with a refuge from the invading oysters and the two bivalves may coexist, provided food is not limiting. 相似文献