ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 353-358 (Sept. 2007), p. 3059-3062 
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: In this paper, a new low-pressure die-casting with degassing function, casting underadjusted pressure (CAP), is proposed. The working principle of CAP process is introduced in details.This paper focuses on the influences of moisture of compressed air on the hydrogen content within themelt aluminum during the cyclic vacuum-pressurizing programs for CAP process. The experimentalresults indicate that degassing under vacuum acts positive in refining aluminum melt. The relativemoisture of compressed air exerts a significant influence on the hydrogen content of aluminum melt.After the melt aluminum is exposed to the air with a relative moisture of 85% for 90 min, thehydrogen content of the melt aluminum can get to 0.4 ml/100g/Al; while under the circumstance ofCAP process, the hydrogen content is maintained between 0.05 and 0.15 ml/100g/Al depending onthe moisture capacity of the air, which virtually has no more influence on the casting qualities. Underthe condition of dry compressed air, the hydrogen content can be kept at a level as low as0.05ml/100g/Al, which facilitates to obtain high air-tightness castings
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: The effects of cold working and heat treatment on caustic stress corrosion cracking (SCC) of mill annealed (MA) alloy 800M in boiling solution of 50%NaOH+0.3%SiO2+0.3%Na2S2O3 were investigated by means of microstructure examination, tensile test, X-ray stress analysis, SCC testing of C-rings, Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and metallography.The microstructure of alloy 800M under tested conditions was austenite. With a train of 25% by cold working, the grains of alloy 800M became longer, yield strength (YS) and ultimate tensile strength (UTS) increased, elongation (δ ) decreased, residual stress and the susceptibility to SCC increased. With increasing temperature of heat treatment of alloy 800M with cold working, the grains became bigger , residual stress, YS and UTS decreased and δ increased, the susceptibility to SCC of alloy 800M decreased. In boiling caustic solution, SCC cracks on the surfaces of C-ring specimens polarized potentiostatically at –20mV/SCE initiated from pitting and propagated along grain boundaries. AES analysis indicated that the surface films on MA alloy 800M were enriched in nickel and depleted in iron and chromium
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 353-358 (Sept. 2007), p. 3063-3066 
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: The influences of Sn addition of 3%-30% on the friction and thermal expansion propertiesof Al-Sn bearing alloys were investigated in this paper. The experiments were carried out on aspecially designed friction testing machine and a dilatometer. It is shown by the experiments that thefriction coefficient and hardness of the alloys decrease with the increasing of Sn content. The frictioncoefficient decreases dramatically when Sn content is higher than 6%. On the other hand, the frictioncoefficient is also dependent on the load. The friction coefficient increases as the load rises. The linearCTE is also a function of temperature and Sn contents. CTE increases when the temperature rises buthas no obvious differences for the alloy system when the temperature is below 80°C. As thetemperature rises, the differences become large among the alloy system. The higher the Sn content,the lower the CTE
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: In the present paper, TiB2/Al composite with 5% volume fraction of TiB2 was fabricated byLSM method. The effects of purification and degassing methods on TiB2/Al composite wereexamined by means of X-ray diffraction (XRD) and image analysis. Hydrogen contents in the moltencomposites were detected and compared among flux, inert gas and vacuum purification processes.The experimental results indicate that under general cast condition a majority of the TiB2 particlesdistribute on grain boundary, and only a few particles disperse within grains. The flux and vacuumpurifications have no virtual impact on the distribution of TiB2 and the fraction of TiB2 remains thesame after purification. However, degassing with inert gas will be detrimental; the TiB2 particles willbe separated and removed from the matrix. The hydrogen contents for flux, inert gas and vacuumprocesses are 0.15ml/100g/Al, 0.12ml/100g/Al and 0.12ml/100g/Al respectively
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Advanced materials research Vol. 51 (June 2008), p. 85-92 
    ISSN: 1662-8985
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: In this investigation, experiments were carried out to study the relationship ofsolidification parameters and the secondary dendrite arm spacing (SDAS) in A357 alloy casting withvarious thicknesses under the same solidification condition. The results show that the cooling ratedecreases as the thickness of specimens increases, the local solidification time increased, and SDASincreased. The relationships between the SDAS and cooling rate and local solidification time underthe condition of furan resin self-hardening sand casting were obtained: SDAS = 20.8 tf 0.3, SDAS =69.34 v -0.3. The mechanical properties have some linear relations with SDAS of A357 alloy afteraging heat treatment. The correlations can be expressed: UTS=410.4-0.8SDAS andEl%=7.9-0.05SDAS
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    s.l. ; Stafa-Zurich, Switzerland
    Advanced materials research Vol. 51 (June 2008), p. 93-98 
    ISSN: 1662-8985
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Hydrogen is the only gas that is appreciably soluble in aluminum and its alloy. Its solubilityis small but its effects on the mechanical properties and finishing characteristics of aluminum alloysare significant. In this paper, a patented degassing process, which is based on the vacuum metallurgyprinciple, is proposed. The diffusion equation was used for explaining hydrogen transfer in the liquidaluminum under the function of a porous sucking head. RPT experiment was carried out to evaluateeffectiveness of the process. The experiment indicates that the hydrogen content can be dramaticallyreduced to 0.05ml/100gAl owing to the use of this new process
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2019-07-13
    Description: The TROPspheric Monitoring Instrument (TROPOMI) on the Sentinel-5 Precursor (Sentinel-5P) is the first of the Atmospheric Composition Sentinels by the European Space Agency (ESA) that provides measurements of ozone, NO2, SO2, CH4, CO, formaldehyde, aerosols and cloud at high spatial, temporal and spectral resolutions. The early afternoon orbit of Sentinel-5P mission provides a strong synergy with the U.S. Suomi National Polar-orbiting Partnership (S-NPP) satellite, especially in that the S-NPP Ozone Monitoring and Profiling Suite (OMPS) facilitates high vertically resolved stratospheric and lower mesospheric ozone profiles. The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) supports over a thousand data collections in the Focus Areas of Atmospheric Composition, Water & Energy Cycles, and Climate Variability and it is the Distributed Active Archive Center (DAAC) that is curating both offline Sentinel-5P TROPOMI and S-NPP OMPS Level-1B (L1B) and Level-2 (L2) products. Through its convenient and enhanced tools/services such as OPeNDAP and L2 Subsetting, GES DISC offers air quality remote sensing user communities facile solutions for complex Earth science data and applications. This presentation will demonstrate TROPOMI and OMPS products including earthview radiance, solar irradiance, and currently available L2 datasets, as well as easy ways to access, visualize and subset data. The implementation of the End User License Agreement (EULA) between NASA GES DISC and all data users accessing data at GES DISC will be emphasized as well.
    Keywords: Earth Resources and Remote Sensing
    Type: GSFC-E-DAA-TN64131 , 2018 ATMOS Conference; 25-29 Nov. 2018; Salzburg; Austria
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2019-07-13
    Description: The Ozone Monitoring Instrument (OMI) is one of the instruments aboard NASA's Aura satellite. It measures ozone total column and vertical profile, aerosols, clouds, and trace gases including NO2, SO2, HCHO, BrO, and OClO using absorption in the ultraviolet electromagnetic spectrum (280 - 400 nm). OMI Level-2G (L2G) products are based on the pixel-level OMI granule satellite measurements stored within global 0.25 deg. X 0.25 deg. grids, therefore they conserve all the Level 2 (L2) spatial and temporal details for 24 hours of scientific data in one file. The second Modern-Era Retrospective analysis for Research and Applications (MERRA-2) is NASA's atmospheric reanalysis, using an upgraded version of Goddard Earth Observing System Model, version 5 (GEOS-5) data assimilation system. MERRA-2 includes aerosol data reanalysis and improved representations of stratospheric ozone, compared with its predecessor MERRA, in both instantaneous and time-averaged collections. It is found that simply comparing satellite Level-3 products might cause biases, due to lack of detailed temporal and original retrieval information. It is therefore preferable to inter-compare or implement satellite derived physical quantities directly with/to model assimilation with as high temporal and spatial resolutions as possible. This study will demonstrate utilization of OMI L2G daily aerosol and ozone products by comparing them with MERRA-2 hourly aerosol/ozone simulations, matched in both space and time aspects. Both OMI and MERRA-2 products are accessible online through NASA Goddard Earth Sciences Data Information Services Center (GES DISC, https://disc.gsfc.nasa.gov/).
    Keywords: Earth Resources and Remote Sensing
    Type: GSFC-E-DAA-TN51980 , American Meteorological Society (AMS) Annual Meeting; 7-11 Jan. 2018; Austin, TX; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2019-07-13
    Description: This paper evaluates the first 15 months of the Ozone Mapping and Profiler Suite (OMPS) Sensor Data Record (SDR) acquired by the nadir sensors and processed by the National Oceanic and Atmospheric Administration Interface Data Processing Segment. The evaluation consists of an inter-comparison with a similar satellite instrument, an analysis using a radiative transfer model, and an assessment of product stability. This is in addition to the evaluation of sensor calibration and the Environment Data Record product that are also reported in this Special Issue. All these are parts of synergetic effort to provide comprehensive assessment at every level of the products to ensure its quality. It is found that the OMPS nadir SDR quality is satisfactory for the current Provisional maturity. Methods used in the evaluation are being further refined, developed, and expanded, in collaboration with international community through the Global Space-based Inter-Calibration System, to support the upcoming long-term monitoring.
    Keywords: Earth Resources and Remote Sensing
    Type: GSFC-E-DAA-TN21489 , Journal of Geophysical Research: Atmospheres; 119; 10; 6170-6180
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2019-07-13
    Description: The recently launched Sentinel satellite mission, the Sentinel-5 Precursor (Sentinel-5P), is one of the European Space Agency's (ESA) new mission family Sentinels. The sole payload on Sentinel-5P is the TROPOspheric Monitoring Instrument (TROPOMI), a nadir-viewing 108 field-of-view push-broom grating hyperspectral spectrometer, covering the wavelengths of ultraviolet-visible (270 nm - 495 nm), near infrared (675 nm - 775 nm), and shortwave infrared (2305 nm - 2385 nm). Sentinel-5P is the first of the Atmospheric Composition Sentinels, and is providing measurements of atmospheric chemistry, aerosols, and clouds at high spatial, temporal, and spectral resolution. The NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) supports over a thousand data collections in the focus areas of Atmospheric Composition, Water & Energy Cycles, and Climate Variability. Sentinel-5P TROPOMI Level-1B (L1B) and Level-2 (L2) products are curated at the GES DISC. Sentinel-5P data are provided by the European Union and the European Space Agency (ESA) through an agreement between ESA and NASA. Through its convenient and enhanced tools/services, such as OPeNDAP and L2 Subsetting, GES DISC offers the air quality remote sensing user community facile solutions for using complex Earth science data and applications. This presentation will demonstrate up-to-date TROPOMI products including EarthView (EV) radiance, solar irradiance, Aerosol Index, Carbon Monoxide, Total column Ozone, Nitrogen Dioxide, and cloud, as well as easy ways to access, visualize and subset TROPOMI data.
    Keywords: Earth Resources and Remote Sensing
    Type: GSFC-E-DAA-TN64130 , AGU Fall Meeting 2018; 10-14 Dec. 2018; Washington, DC; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...