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
  • 1
    facet.materialart.
    Unknown
    A closer look at water-related geologic activity on Mars (2007)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2007-09-22
    Description: Water has supposedly marked the surface of Mars and produced characteristic landforms. To understand the history of water on Mars, we take a close look at key locations with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter, reaching fine spatial scales of 25 to 32 centimeters per pixel. Boulders ranging up to approximately 2 meters in diameter are ubiquitous in the middle to high latitudes, which include deposits previously interpreted as finegrained ocean sediments or dusty snow. Bright gully deposits identify six locations with very recent activity, but these lie on steep (20 degrees to 35 degrees) slopes where dry mass wasting could occur. Thus, we cannot confirm the reality of ancient oceans or water in active gullies but do see evidence of fluvial modification of geologically recent mid-latitude gullies and equatorial impact craters.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉McEwen, A S -- Hansen, C J -- Delamere, W A -- Eliason, E M -- Herkenhoff, K E -- Keszthelyi, L -- Gulick, V C -- Kirk, R L -- Mellon, M T -- Grant, J A -- Thomas, N -- Weitz, C M -- Squyres, S W -- Bridges, N T -- Murchie, S L -- Seelos, F -- Seelos, K -- Okubo, C H -- Milazzo, M P -- Tornabene, L L -- Jaeger, W L -- Byrne, S -- Russell, P S -- Griffes, J L -- Martinez-Alonso, S -- Davatzes, A -- Chuang, F C -- Thomson, B J -- Fishbaugh, K E -- Dundas, C M -- Kolb, K J -- Banks, M E -- Wray, J J -- New York, N.Y. -- Science. 2007 Sep 21;317(5845):1706-9.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, USA. mcewen@lpl.arizona.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17885125" target="_blank"〉PubMed〈/a〉
    Keywords: Extraterrestrial Environment ; Geological Phenomena ; Geology ; *Mars ; *Water
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    Seasonal erosion and restoration of Mars' northern polar dunes (2011)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2011-02-05
    Description: Despite radically different environmental conditions, terrestrial and martian dunes bear a strong resemblance, indicating that the basic processes of saltation and grainfall (sand avalanching down the dune slipface) operate on both worlds. Here, we show that martian dunes are subject to an additional modification process not found on Earth: springtime sublimation of Mars' CO(2) seasonal polar caps. Numerous dunes in Mars' north polar region have experienced morphological changes within a Mars year, detected in images acquired by the High-Resolution Imaging Science Experiment on the Mars Reconnaissance Orbiter. Dunes show new alcoves, gullies, and dune apron extension. This is followed by remobilization of the fresh deposits by the wind, forming ripples and erasing gullies. The widespread nature of these rapid changes, and the pristine appearance of most dunes in the area, implicates active sand transport in the vast polar erg in Mars' current climate.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hansen, C J -- Bourke, M -- Bridges, N T -- Byrne, S -- Colon, C -- Diniega, S -- Dundas, C -- Herkenhoff, K -- McEwen, A -- Mellon, M -- Portyankina, G -- Thomas, N -- New York, N.Y. -- Science. 2011 Feb 4;331(6017):575-8. doi: 10.1126/science.1197636.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Planetary Science Institute, Tucson, AZ 85719, USA. cjhansen@psi.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/21292976" target="_blank"〉PubMed〈/a〉
    Keywords: *Carbon Dioxide ; Dry Ice ; Extraterrestrial Environment ; *Mars
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    Electronic Resource
    Electronic Resource
    Hydration of stratum corneum (1973)
    New York : Wiley-Blackwell
    Biopolymers 12 (1973), S. 2789-2802 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A model for the hydration behavior of human stratum corneum has been developed from measurements on in vitro samples isolated in a manner which minimized tissue treatment and trauma. Water sorption/desorption rate measurements as a function of water activity, temperature, and tissue integrity are reported. These data, together with thermodynamic data (infrared and nmr results reported earlier) are consistent with a model in which rapidly sorbed/desorbed water (ca. 0.5 mg water/mg stratum corneum) is associated with (“bound” by) the tissue, while slowly sorbed/desorbed “free” water (up to 12 mg water/mg stratum corneum) is kinetically restricted and probably intracellular in location. Both equilibrium water binding and desorption kinetic data suggest structural changes of this cellular water barrier upon hydration. Evidence for hysteresis in water sorption isotherms (reported by others) could not be reproduced.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1973.360121212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The influence of ionic strength and pH on the aggregation properties of zinc-free insulin studied by static and dynamic laser light scattering (1993)
    New York : Wiley-Blackwell
    Biopolymers 33 (1993), S. 1643-1657 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The aggregation properties of zinc-free insulin have been studied using static and dynamic light scattering. The aggregation has been investigated as a function of three parameters, the concentration of sodium chloride (in the range 10-100 mM), the pH value (in the range pH 7.5-10.5), and the insulin concentration (1.8-13.4 mg/mL). The measured homodyne autocorrelation function was used to determine the apparent mean hydrodynamic diameter as well as the apparent weight-averaged molar mass of the insulin species in solution. A method of data analysis was employed, which allows the separation of light scattering contributions from the insulin oligomers and from irrelevant macromolecules and possible impurities present in the sample solutions. Also, a simple phenomenological equilibrium model describing the association of oligomers of insulin is presented. One aspect of this model is that it makes it possible to determine weight average molar masses corrected for virial effects on the Rayleigh ratio. This was necessary because virial effects cannot be isolated and corrected for by dilution since this would change the equilibrium distribution of oligomers. The basis of the model is a positive contribution to Gibbs free energy from charge repulsion depending on the protein charge and the number of monomers in the oligomers, and an assumed constant negative contribution to Gibbs free energy arising from either an entropic gain or hydrogen bonding upon association. The equilibrium model gives a good description of both the apparent weight average molar masses and the apparent hydrodynamic diameters, when the effect of the insulin concentration is taken into account by including virial effects arising from charge-charge repulsion (Donnan effect). The result shows that the association of insulin as a function of pH and ionic strength can be described by an effective charge equal to the charge derived from proton titration reduced by the number of sodium ions binding to insulin. At the lowest pH and highest salt concentration (pH 7.5, 100 mM NaCl, 12 mg/mL insulin), the weight average molar mass is close to that of the hexamer, and at the highest pH and lowest salt concentration (pH 10.5, 10 mM NaCl, 1.9 mg/mL), the weight average molar mass is close to that of the monomer. In all cases, however, a distribution of oligomers is present with a relative Gaussian width of about 30%. Neglecting the positive term in Gibbs free energy, an upper bound to the association constant for insulin can be calculated: The negative term in Gibbs free energy corresponds to an association constant of (0.8 ± 0.3)·105M-1, which is in agreement with published values for the monomer-to-monomer association. The satisfactory agreement between theory and experiments for the weight average molar mass suggests that it should be possible to predict the aggregational properties of mutant forms of insulin. © 1993 John Wiley & Sons, Inc.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360331103
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A study of the enhanced oxidation of poly-N-vinylimidazole films on copper (1996)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 34 (1996), S. 611-621 
    Details
    ISSN: 0887-6266
    Keywords: copper ; corrosion ; poly-N-vinylimidazole ; oxidation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The degradation of poly-N-vinylimidazole films on copper substrates was studied by Fourier transform infrared spectroscopy and x-ray photoelectron spectroscopy. Infrared measurements on samples heated at 300°C for 15 minutes revealed that the oxidation of the polymer was accelerated by the copper. X-ray photoelectron spectroscopy showed that a layer of copper oxide was formed on top of the oxidized film. Copper ions were also detected within the polymer layer. © 1996 John Wiley & Sons, Inc.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
  • 6
    Electronic Resource
    Electronic Resource
    The formation of polymerizable tubules (1990)
    New York, NY : Wiley-Blackwell
    Polymers for Advanced Technologies 1 (1990), S. 27-32 
    Details
    ISSN: 1042-7147
    Keywords: Crystallization ; Phospholipids ; Diacetylene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: We have been investigating the crystallization behavior of the phospholipid amphiphile, 1,2 bis (10, 12-tricosadiynol)-sn-glycero-3-phosphocholine, DC8,9PC, which forms both vesicles and hollow tubules as well as Langmuir Blodgett monolayers and multilayers. This material has polymerizable diacetylene groups in equivalent positions on the two hydrocarbon tails. The direct crystallization from solution of this amphiphile has been studied using different solvent mixtures and temperatures. The Langmuir Blodgett technique was also used to compress and orient the tubules.
    Additional Material: 15 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pat.1990.220010105
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Osmotic pressure measurements of ethyl acrylate polymers. I. Dependence of molecular weight on conversion (1951)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 7 (1951), S. 77-82 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: By employing the solution polymerization method, ethyl acrylate was readily polymerized, giving a product soluble in a number of organic solvents. By using benzene as the solvent, polymers of exceptionally high molecular weights were produced. The polymer samples were obtained by precipitation after the polymerization had proceeded for various periods of time. The slopes of the osmotic pressure curves were substantially constant for all the polymers. It is concluded that chain transfer to polymer during the polymerization process is insignificant and that the ethyl acrylate polymers do not contain any branched sites. It can be inferred from these data that the insolubility of ethyl polyacrylates frequently encountered is predominantly due to the extremely high molecular weights of the polymers.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1951.120070106
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Mechanism of emulsion polymerization of styrene with persulfate as activator in the absence and presence of mercaptan and a retarderThe work discussed herein was performed as a part of the research project sponsored by the Reconstruction Finance Corporation, Office of Synthetic Rubber, in connection with the Government Synthetic Rubber Program. (1955)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 15 (1955), S. 459-473 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: With the use of persulfate containing radioactive sulfur it is shown that the termination reaction of the polymerization of styrene is a coupling of the free radical chains. In the presence of m-dinitrobenzene as a retarder evidence has been presented that the termination reaction is a disproportionation and not a combination of two free radical chains. Mercaptan in the emulsion polymerization of styrene acts solely as a chain transfer agent. Any chemical reaction between persulfate and mercaptan does not contribute to the initiation. In the presence of detergent the rate of initiation of the polymerization of styrene is equal to the rate of thermal dissociation of persulfate: \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm S}_2 {\rm O}_{\rm 8}^{ - - } \to 2{\rm SO}_4 ^ - . $\end{document} Thus, any reaction between persulfate with monomer and detergent does not contribute to the initiation. The much smaller rate of initiation in the absence of detergent is attributed to the slight solubility of styrene, the concentration of the monomer being so small that it cannot capture all the free radicals. The effect of the detergent is a physical one, by its solubilizing action it increases the solubility of the monomer in the water layer to such an extent that the “activator” now becomes 100% efficient.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1955.120158012
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    The ice-core record - Climate sensitivity and future greenhouse warming (1990)
    In:  Other Sources
    Details
    Publication Date: 2011-08-19
    Description: The prediction of future greenhouse-gas-warming depends critically on the sensitivity of earth's climate to increasing atmospheric concentrations of these gases. Data from cores drilled in polar ice sheets show a remarkable correlation between past glacial-interglacial temperature changes and the inferred atmospheric concentration of gases such as carbon dioxide and methane. These and other palaeoclimate data are used to assess the role of greenhouse gases in explaining past global climate change, and the validity of models predicting the effect of increasing concentrations of such gases in the atmosphere.
    Keywords: GEOPHYSICS
    Type: Nature (ISSN 0028-0836); 347; 139-145
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 10
    facet.materialart.
    Unknown
    Light scattering in planetary atmospheres (1974)
    In:  Other Sources
    Details
    Publication Date: 2011-08-16
    Description: This paper reviews scattering theory required for analysis of light reflected by planetary atmospheres. Section 1 defines the radiative quantities which are observed. Section 2 demonstrates the dependence of single-scattered radiation on the physical properties of the scatterers. Section 3 describes several methods to compute the effects of multiple scattering on the reflected light.
    Keywords: GEOPHYSICS
    Type: Space Science Reviews; 16; Oct. 197
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...