ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry  (7)
  • Astronomy
  • J24
  • J31
  • Lunar and Planetary Science and Exploration
  • Q11
  • 2015-2019  (12)
  • 1
    facet.materialart.
    Unknown
    Geotechnical Tests on Asteroid Simulant Orgueil (2017)
    In:  CASI
    Details
    Publication Date: 2019-07-12
    Description: In the last 100 years, the global population has more than quadrupled to over seven billion people. At the same time, the demand for food and standard of living has been increasing which has amplified the global water use by nearly eight times from approximately 500 to 4000 cu km per yr from 1900 to 2010. With the increasing concern to sustain the growing population on Earth it is necessary to seek other approaches to ensure that our planet will have resources for generations to come. In recent years, the advancement of space travel and technology has allowed the idea of mining asteroids with resources closer to becoming a reality. During the duration of the internship at NASA Kennedy Space Center, several geotechnical tests were conducted on BP-1 lunar simulant and asteroid simulant Orgueil. The tests that were conducted on BP-1 was to practice utilizing the equipment that will be used on the asteroid simulant and the data from those tests will be omitted from report. Understanding the soil mechanics of asteroid simulant Orgueil will help provide basis for future technological advances and prepare scientists for the conditions they may encounter when mining asteroids becomes reality in the distant future. Distinct tests were conducted to determine grain size distribution, unconsolidated density, and maximum density. Once the basic properties are known, the asteroid simulant will be altered to different levels of compaction using a vibrator table to see how compaction affects the density. After different intervals of vibration compaction, a miniature vane shear test will be conducted. Laboratory vane shear testing is a reliable tool to investigate strength anisotropy in the vertical and horizontal directions of a very soft to stiff saturated fine-grained clayey soil. This test will provide us with a rapid determination of the shear strength on the undisturbed compacted regolith. The results of these tests will shed light on how much torque is necessary to drill through the surface of an asteroid. Most of the known asteroids are believed to be left over material during the formation of the solar system that never accreted to form planets. Asteroids can be found in several groups such as Trojan Asteroids, Near Earth Asteroids (NEAs) and the main asteroid belt. The Trojan Asteroids orbit the 4th and 5th Lagrange points of major planets in the Solar System while the NEA's have orbits that are close to and sometimes intersect with Earths orbit and the Main Asteroid Belt which is found between the orbit of Mars and Jupiter. Gravitational perturbations can alter the orbit of asteroids in the Main Asteroid Belt causing them to move closer to earth causing them to become in the NEA class.
    Keywords: Lunar and Planetary Science and Exploration
    Type: KSC-E-DAA-TN42077
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    OSIRISREx Visible and NearInfrared Observations of the Moon (2019)
    In:  Other Sources
    Details
    Publication Date: 2020-01-04
    Description: The Origins, Spectral Interpretation, Resource Identification, and Security Regolith Explorer(OSIRISREx) mission observed the The Origins, Spectral Interpretation, Resource Identification, and SecurityRegolith Explorer (OSIRISREx) mission observed the Moon during the spacecraft's Earth gravity assist in 2017. From the spacecraft view, the lunar phase was 42, and the inview hemisphere was dominated by anorthositic highlands terrain. Lunar spectra obtained by the OSIRISREx Visible and InfraRed Spectrometer show evidence of several candidate absorption features. We observe the 2.8m hydration band, confirming the spectral results from other missions, but detected in fulldisk spectra. We also tentatively identify weak spectral features near 0.9 and 1.3 m, consistent with lunar regolith containing a mixture of plagioclase and orthopyroxene minerals, as expected for highlands terrain.
    Keywords: Lunar and Planetary Science and Exploration
    Type: GSFC-E-DAA-TN76610 , Geophysical Research Letters (ISSN 0094-8276) (e-ISSN 1944-8007); 46; 12; 6322-6326
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Ground-Based Navigation and Dispersion Analysis for the Orion Exploration Mission 1 (2016)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: This paper presents the Orion Exploration Mission 1 Linear Covariance Analysis for the DRO mission using ground-based navigation. The Delta V statistics for each maneuver are presented. In particular, the statistics of the lunar encounters and the Entry Interface are presented.
    Keywords: Lunar and Planetary Science and Exploration
    Type: JSC-CN-35077 , AAS/AIAA Space Flight Mechanics Meeting; Feb 14, 2016 - Feb 18, 2016; Napa, CA; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    A Low-Power Correlator ASIC for Arrays with Many Antennas (2016)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: We report the design of a new application-specific integrated circuit (ASIC) for use in radio telescope correlators. It supports the construction of correlators for an arbitrarily large number of signals. The ASIC uses an intrinsically low-power architecture along with design techniques and a process that together result in unprecedentedly low power consumption. The design is flexible in that it can support telescopes with almost any number of antennas N. It is intended for use in an "FX" correlator, where a uniform filter bank breaks each signal into separate frequency channels prior to correlation.
    Keywords: Astronomy
    Type: United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM); Jan 06, 2016 - Jan 09, 2016; Boulder, CO; United States
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    An Integrated Circuit for Radio Astronomy Correlators Supporting Large Arrays of Antennas (2016)
    In:  Other Sources
    Details
    Publication Date: 2019-08-26
    Description: Radio telescopes that employ arrays of many antennas are in operation, and ever larger ones are being designed and proposed. Signals from the antennas are combined by cross-correlation. While the cost of most components of the telescope is proportional to the number of antennas N, the cost and power consumption of cross-correlationare proportional to N2 and dominate at sufficiently large N. Here we report the design of an integrated circuit (IC) that performs digital cross-correlations for arbitrarily many antennas in a power-efficient way. It uses an intrinsically low-power architecture in which the movement of data between devices is minimized. In a large system, each IC performs correlations for all pairs of antennas but for a portion of the telescope's bandwidth (the so-called "FX" structure). In our design, the correlations are performed in an array of 4096 complex multiply-accumulate (CMAC) units. This is sufficient to perform all correlations in parallel for 64 signals (N=32 antennas with 2 opposite-polarization signals per antenna). When N is larger, the input data are buffered in an on-chipmemory and the CMACs are re-used as many times as needed to compute all correlations. The design has been synthesized and simulated so as to obtain accurate estimates of the IC's size and power consumption. It isintended for fabrication in a 32 nm silicon-on-insulator process, where it will require less than 12mm2 of silicon area and achieve an energy efficiency of 1.76 to 3.3 pJ per CMAC operation, depending on the number of antennas. Operation has been analyzed in detail up to N = 4096. The system-level energy efficiency, including board-levelI/O, power supplies, and controls, is expected to be 5 to 7 pJ per CMAC operation. Existing correlators for the JVLA (N = 32) and ALMA (N = 64) telescopes achieve about 5000 pJ and 1000 pJ respectively usingapplication-specific ICs in older technologies. To our knowledge, the largest-N existing correlator is LEDA atN = 256; it uses GPUs built in 28 nm technology and achieves about 1000 pJ. Correlators being designed for the SKA telescopes (N = 128 and N = 512) using FPGAs in 16nm technology are predicted to achieve about 100 pJ.
    Keywords: Astronomy
    Type: Journal of Astronomical Instrumentation; 5; 2; 1650002
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    So close, so different: geothermal flux shapes divergent soil microbial communities at neighbouring sites (2016)
    Wiley-Blackwell
    Details
    Publication Date: 2021-06-14
    Description: This study is focused on the (micro)biogeochemical features of two close geothermal sites (FAV1 and FAV2), both selected at the main exhalative area of Pantelleria Island, Italy. A previous biogeochemical survey revealed high CH4 consumption and the presence of a diverse community of methanotrophs at FAV2 site, whereas the close site FAV1 was apparently devoid of methanotrophs and recorded no CH4 consumption. Next-Generation Sequencing (NGS) techniques were applied to describe the bacterial and archaeal communities which have been linked to the physicochemical conditions and the geothermal sources of energy available at the two sites. Both sites are dominated by Bacteria and host a negligible component of ammonia-oxidizing Archaea (phylum Thaumarchaeota). The FAV2 bacterial community is characterized by an extraordinary diversity of methanotrophs, with 40% of the sequences assigned to Methylocaldum, Methylobacter (Gammaproteobacteria) and Bejerickia (Alphaproteobacteria); conversely, a community of thermo-acidophilic chemolithotrophs (Acidithiobacillus, Nitrosococcus) or putative chemolithotrophs (Ktedonobacter) dominates the FAV1 community, in the absence of methanotrophs. Since physical andchemical factors of FAV1, such as temperature and pH, cannot be considered limiting for methanotrophy, it is hypothesized that the main limiting factor for methanotrophs could be high NH4+ concentration. At the same time, abundant availability of NH4+ and other high energy electron donors and acceptors determined by the hydrothermal flux in this site create more energetically favourable conditions for chemolithotrophs that outcompete methanotrophs in non-nitrogen-limited soils.
    Description: Published
    Description: 150–162
    Description: 4V. Vulcani e ambiente
    Description: JCR Journal
    Description: restricted
    Keywords: geothermal soils ; geomicrobiology ; chemolithotrophs ; methanotrophs ; Pantelleria ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    New mafic magma refilling a quiescent volcano: Evidence from He-Ne-Ar isotopes during the 2011–2012 unrest at Santorini, Greece (2015)
    Details
    Publication Date: 2017-04-04
    Description: n 2011-2012 Santorini was characterized by seismic-geodetic-geochemical unrest, which was unprecedented since the most-recent eruption occurred in 1950 and led to fear an eruption was imminent. This unrest offered a chance for investigating the processes leading to volcanic reactivation and the compositional characteristics of involved magma. We have thus analyzed the He-Ne-Ar-isotope composition of fluid inclusions in olivines and clinopyroxenes from cumulate mafic enclaves hosted in cogenetic dacitic lavas of the 1570–1573 and 1925–1928 eruptions of Nea Kameni. These unique data on Aegean volcanism were compared with those of gases collected in quiescent periods and during the unrest. The 3He/4He-ratios (3.1–4.0Ra) are significantly lower than the typical arc-volcano values (R/Ra~7–8), suggesting the occurrence of magma contamination in Santorini plumbing system, which would further modify the 3He/4He-ratio of parental magmas generated in the local metasomatized mantle. The 3He/4He-values of enclaves (3.1–3.6Ra) are comparable to those measured in gases during quiescent periods, confirming that enclaves reflect the He-isotope signature of magma residing at shallow depths and feeding passive degassing. A significant increase in soil CO2 flux from Nea Kameni and anomalous compositional variations in the fumaroles were identified during the unrest, accordingly with previous studies. Simultaneously, 3He/4He-ratios up to 4.0Ra were also measured, demonstrating that the unrest was due to the intrusion into the shallow plumbing system of a more-primitive 3He-rich magma, which is even volatile richer and less contaminated than mafic magma erupted as enclaves. This new intrusion did not however trigger an eruption.
    Description: Published
    Description: 798–814
    Description: 1V. Storia e struttura dei sistemi vulcanici
    Description: 2V. Dinamiche di unrest e scenari pre-eruttivi
    Description: JCR Journal
    Description: restricted
    Keywords: Santorini ; 3He/4He ratio ; enclave ; fluid inclusion ; mafic magma ; magma intrusion ; unrest ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases ; 04. Solid Earth::04.08. Volcanology::04.08.05. Volcanic rocks ; 04. Solid Earth::04.08. Volcanology::04.08.06. Volcano monitoring
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    GEOCHEMISTRY OF THE GAS MANIFESTATIONS OF GREECE: METHANE AND LIGHT HYDROCARBONS (2016)
    Bulletin of the Geological Society of Greece
    Details
    Publication Date: 2019-01-09
    Description: Greece has a very complex geodynamic setting deriving from a long and complicat-ed geological history being characterized by intense seismic activity and enhanced geothermal gradient. This activity, with the contribution of an active volcanic arc, favours the existence of many gas manifestations. Depending on the prevailing gas species, the latter can be subdivided in three main groups: CO2-, N2- and CH4-dominated. In the present work, we focus on methane and light hydrocarbons (C2-C6) to define their origin. CH4 concentrations (〈2 to 915,200 μmol/mol) and isotop-ic ratios (δ13C -79.8 to +16.9 ‰, δD -298 to +264‰) cover a wide range of values indicating different origins and/or secondary post-genetic processes. Samples from gas discharged along the Ionian coast and in northern Aegean Sea have a prevail-ing microbial origin. Cold and thermal gas manifestations of central and northern Greece display a prevalent thermogenic origin. Methane in gases released along the active volcanic arc is prevailingly abiogenic, although thermogenic contributions cannot be excluded. Gases collected in the geothermal areas of Sperchios basin and northern Euboea are likely affected by strong secondary oxidation processes, as suggested by their highly positive C and H isotopic values (up to +16.9‰ and +264‰ respectively) and low C1/(C2+C3) ratios.
    Description: Submitted
    Description: Thessaloniki, Greece
    Description: 4V. Vulcani e ambiente
    Description: open
    Keywords: Hellenic territory ; hydrothermal gases ; cold gas emissions ; origin of hydrocarbon gases ; 03. Hydrosphere::03.04. Chemical and biological::03.04.05. Gases ; 03. Hydrosphere::03.04. Chemical and biological::03.04.06. Hydrothermal systems ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry ; 04. Solid Earth::04.08. Volcanology::04.08.01. Gases
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: Conference paper
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    Dissolved inert gases (He, Ne and N2) as markers of groundwater flow and degassing areas at Mt Etna volcano (Italy) (2016)
    Elsevier Science Limited
    Details
    Publication Date: 2017-04-04
    Description: Fractions of the volatiles ascending from magma chambers meet groundwaters flowing away from the volcano summit and are carried to great distance as dissolved gases. The complex interactions between ascending magmatic volatiles, tectonic structures, heterogeneities in rock permeability and flow lines of aquifers deeply affect the dispersion of the dissolved species. Studying the spatial distribution of such species can therefore provide valuable information on the circulation of fluids inside volcanic edifices. Our study focussed on the composition of dissolved inert gases (He, Ne and N2) and He isotope ratio (3He/4He) in groundwaters circulating at Mt Etna volcano (Italy), because the concentrations of these species differ markedly between magmatic and shallow(crustal and atmospheric) sources, and they do not interact chemically with rocks. We identified groundwaters that flow through anomalously degassing areas associated with clearly evident or known tectonic structures. These waters show a typically magmatic He isotope composition (high 3He/4He ratios) and high proportions of dissolved magmatic gases (He and CO2) compared to the atmospheric ones (Ne and N2). Downstream of the degassing structures, along the hydrological outflows, we found groundwaters that are progressively enriched in atmospheric-derived gases (Ne and N2) and exhibited lower 3He/4He ratios. On this basis, we set up a model of unidimensional dispersion-advection of inert volatile solutes, coupled with a two-layer model for the dynamic exchange of volatiles through the aquifer–atmosphere interface. The model is able to quantitatively explain the progressive dilution of the magmatic signal over distances of several kilometres from the source location of the anomaly towards the final part of the flow lines at the coast. Typical hydrogeological parameters such as the flow velocity, rock permeability and rate of air–groundwater interaction can be constrained, and underground pathways of waters can be identified. Waters that are anomalously rich in magmatic tracers with respect to their peripheral position along the flowlines reflect arrival of deep gases frombelow, and they therefore offer a powerful tool for revealing hidden tectonic structures.
    Description: Published
    Description: 10-21
    Description: 1V. Storia e struttura dei sistemi vulcanici
    Description: JCR Journal
    Description: restricted
    Keywords: Dissolved gas in water ; Noble gas geochemistry ; Groundwater flow ; Nitrogen geochemistry ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Trace elements mobility in soils from the hydrothermal area of Nisyros (Greece) (2015)
    Details
    Publication Date: 2019-01-09
    Description: Nisyros Island, Greece, is a stratovolcano known for its intense hydrothermal activity. On June 2013, during a multidisciplinary field campaign, soil samples were collected in the caldera area to determinate the main mineralogical assemblages and to investigate the distribution of trace element concentrations and the possible relationship to the contribution of fluids of deep origin. Soil samples were analysed with XRD and for the chemical composition of their leachable (deionized water) and pseudo total (microwave digestion) fraction both for major and trace elements. The results allow to divide the samples in 2 groups: Lakki Plain and Stefanos Crater. The latter, where a fumarolic area is located, shows a mineralogical assemblage dominated by phases typical of hydrothermal alteration. Their very low pH values (1.9 – 3.4) show the strong impact of fumarolic gases which are probably also the cause of strong enrichments in these soils of highly volatile elements like S, As, Se, Bi, Sb, Tl and Te.
    Description: Published
    Description: 2SR. VULCANI - Servizi e ricerca per la Società
    Description: JCR Journal
    Description: open
    Keywords: Trace elements ; Hydrothermal alteration ; 01. Atmosphere::01.01. Atmosphere::01.01.07. Volcanic effects ; 03. Hydrosphere::03.04. Chemical and biological::03.04.06. Hydrothermal systems ; 04. Solid Earth::04.02. Exploration geophysics::04.02.01. Geochemical exploration ; 04. Solid Earth::04.04. Geology::04.04.12. Fluid Geochemistry
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...