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
  • National Academy of Sciences  (11)
  • American Institute of Physics (AIP)  (8)
  • 2000-2004  (9)
  • 1985-1989  (10)
  • 1
    Electronic Resource
    Electronic Resource
    A vacuum gauge using positive temperature coefficient thermistor as the sensor (2000)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 71 (2000), S. 4670-4673 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A vacuum gauge has been designed and fabricated using a new type of sensor element, the semiconducting barium titanate positive temperature coefficient (PTC) thermistor. It covers a much wider range and better resolution compared to conventional Pirani gauge and other thermistor vacuum gauges particularly in the low vacuum levels due to its extreme high temperature coefficient. The details of design criteria of the instrument and its performance characteristics have been discussed. Due to the unique autocurrent limiting and stabilizing capabilities of a PTC thermistor, the fabrication of the instrument appears to be much cheaper. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1287619
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Self-consistent T-matrix solution for the effective elastic properties of perfectly disordered multiphase solids (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 1809-1813 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A self-consistent solution for the effective elastic properties of polycrystalline and perfectly disordered multiphase composites has been discussed by using the T-matrix method under certain suitable approximations. Compared to the existing formulas these new relations for the disordered composites are very useful in practical situations for a quick and more accurate estimate of the effective elastic properties, in particular for a case where the composite has components with widely different values of the elastic constants. For comparison we have discussed the results based on Kröner's theory which also purports to solve the same problem. It is found that the two solutions do not agree. To resolve the difference we take help of Hill's exact solution of the composite problem when the components have equal rigidities. It is found that while Kröner's theory is inconsistent with the exact result the present self-consistent solution analytically reproduces it. Another interesting finding of the present investigation is that the approximations made in obtaining the self-consistent solution are exact in the limit of composites with equal-shear moduli. Finally it is indicated that although the results for composites have been derived for isotropic and cubic components it can be easily adapted for a composite with noncubic components.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.336032
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Method for producing neutral and negative hydrogen particles applicable to hot plasma diagnosis (1988)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 59 (1988), S. 2158-2162 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A method is described whereby a beam of positive hydrogen ions incident at grazing angles on an array of cesium-covered tungsten foils is used to produce H0 and H− particles by negative surface ionization. The results of these experiments indicate that the method can provide diagnostic beams of particles to hot plasmas and can also energy-analyze charge exchange neutrals emerging from hot plasmas.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1139979
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    A Green's function approach to third-order elastic constants of disordered solids (1986)
    College Park, Md. : American Institute of Physics (AIP)
    Journal of Mathematical Physics 27 (1986), S. 2807-2812 
    Details
    ISSN: 1089-7658
    Source: AIP Digital Archive
    Topics: Mathematics , Physics
    Notes: Starting from a Lippmann–Schwinger-type equation, which is very similar to that of quantum mechanical multiple scattering theory, Zeller and Dederichs [Phys. Status Solidi B 55, 831 (1973)] have developed the effective medium theory. This theory has found wide application in understanding the mechanical behavior of disordered solids. However, unlike the problem in quantum mechanics, this equation of the random elasticity is only approximate since this is a linear response theory. So, it is proposed in this work for the first time to go beyond this approximation to treat nonlinear properties of such solids of which the third-order elastic constant is a generic. Again, so far as the nonlinear elastic behavior of these solids is concerned, no work has been done except the simple Voigt- and Reuss-type averaging. Both are extreme approximations and are, moreover, known to lead to violation of the equilibrium condition. The salient feature of the present calculation is to get an exact formal solution of the problem in terms of an appropriate Green's function in a closed form. The result obtained is quite general and may be adopted to treat nonlinearity in any tensor property of disordered materials. Finally several approximations, including a self-consistent solution, have been discussed for obtaining the effective nonlinear static mechanical susceptibility.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.527256
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Sensitive measurement of absolute two-photon absorption cross sections (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 112 (2000), S. 9201-9205 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We develop a method for measuring absolute two-photon absorption cross sections (σ2) and employ it to determine the σ2 of Rhodamine-6G in methanol (16.2±2.4 GM at 806 nm). Our measurement calibrates the relative excitation spectrum previously reported for this chromophore. The method is based on our derivation of an analytical expression describing the transmission of Gaussian laser pulses through a two-photon absorbing medium. The expression is valid for arbitrary absorber thickness, at all distances from the focus. This generalizes the prevalent "z-scan" (translation of the sample along the beam direction) technique for measuring two-photon absorbance, removing the requirements of a "thin" (thickness (very-much-less-than) Rayleigh range of the focused laser beam) sample and of placing the sample at the focus. This leads to an improvement of the sensitivity of the technique by over two orders of magnitude, enabling measurement of the two-photon absorption cross sections of even weakly absorbing specimens at moderate intensities. The results are significant for applications such as nonlinear microscopy, optical data storage and optical power limiting. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.481540
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Humidity sensor using porous tape cast alumina substrate (2001)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 72 (2001), S. 2792-2795 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Moisture sensors based on porous alumina were designed and fabricated to detect and measure the concentration of moisture in gases. In the thin alumina disks taken, the surface and penetration effect has been considered during the process of adsorption and absorption of water molecules through pores and grain boundaries. Three different fabrication techniques, the tape casting technique, pelletization, and porous thick film, have been tried to achieve the desired moisture-sensing property of the samples. Different types of electrode structures and designs were also investigated and optimized to obtain maximum sensitivity. Electrodes were formed by screen printing the samples with thick film conductive pastes. The planar porous alumina sensor so obtained is found to be sensitive in the range of the 100–1000 ppmv level of moisture. The response time of the sensor in the ppmv range is approximately 2 min, and at higher concentrations of moisture it shows quasilinear dependency on the moisture content. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1367357
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Elastic properties of a computer-simulated polycrystalline aggregate of a single component (1985)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 57 (1985), S. 1844-1848 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A simple procedure involving sound velocities in component crystallites has been developed to calculate the effective elastic properties of a hypothetical aggregate which is macroscopically homogeneous but has fluctuations on a microscopic scale, with the underlying assumption that the sound wave can distinguish between the different crystallites oriented at random. For comparison we have also employed the effective medium theory based on a static deformation scheme to calculate the effective elastic properties of the same hypothetical aggregate. Both the procedures use the identical set of input data. Although the assumptions on which the above dynamic and static methods are based are entirely different the results obtained from them for seventeen different aggregates are remarkably close to each other and also to experiments done on polycrystalline specimens using ultrasonic velocities. Finally, a critical discussion of the results and their consequences is presented.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.334413
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Two-dimensional turbulent boundary layers over rigid and moving swept wavy surfaces (1986)
    [S.l.] : American Institute of Physics (AIP)
    Physics of Fluids 29 (1986), S. 964-970 
    Details
    ISSN: 1089-7666
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The two-dimensional, incompressible, turbulent boundary layer over a flexible wall is analyzed. The wall consists of sinusoidal waves that are swept with respect to the flow direction. The mean flow is a boundary layer with wave-induced stresses. These stresses are evaluated from the solution of the linear problem. It is found that the small mean skin friction reduction, observed for the case of zero sweep, persists. The pressure drag reduces for swept wavy wall from its value for no sweep. There is a small drag reduction for the moving wall cases even for the lowest phase speed considered. Within the assumptions of the turbulence model used, a possible drag reduction mechanism is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.865691
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    facet.materialart.
    Unknown
    Specificity and robustness in transcription control networks (2002)
    National Academy of Sciences
    Details
    Publication Date: 2002-02-19
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Identification and subcellular localization of proteins that are rapidly phosphorylated in tyrosine in response to colony-stimulating factor 1. (1988)
    National Academy of Sciences
    Details
    Publication Date: 1988-11-01
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...