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
    ISSN: 1434-601X
    Keywords: 23.20.Lv ; 27.60.+j ; 21.60.Cs
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract An extended level scheme of109Sn is presented showing high-spin states up to Ex≈ 8 MeV and spins up toJπ=(41/2+). Their decay to the 5/2+ ground state has been observed identifying a 12.8 keV 7/2+ → 5/2+ transition. A half-life of T1/2=7(1) ns has been measured for the 17/2+ state atE x =2114 keV. The experimental data are compared with the predictions of shell-model calculations.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 339 (1991), S. 231-238 
    ISSN: 1434-601X
    Keywords: 21.10.Pc ; 25.70.−z ; 25.85.−w
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The correspondence of classical dynamical chaos and statistical properties of the energy spectrum has been investigated for the single-particle motion in strongly deformed nuclear potentials with axial symmetry. The properties of the classical and of the quantized system were analyzed for two potentials: the two-center well potential of finite depth and the two-center oscillator shell model. It has been found that in such mean fields the occurrence of fully developed random matrix statistics is a generic feature corresponding to a global instability of classical trajectories. But due to the absence of scaling invariance, for the general case with a mixed phase space a significant energy dependence of the chaotic phase-space volume has been obtained so that the over-all level-spacing distribution cannot be specified by the chaotic volume as a single parameter. The reason for the appearance of chaoticity turns out to be rather complex. Besides the expected important role of large deformations of high multipolarity, including the neck degree of freedom, the spin-orbit part of the nuclear interaction can also be responsible for the occurrence of dynamical chaos.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1434-601X
    Keywords: 23.20.Ck ; 27.50+e ; 21.60.−n
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Low-lying states of theN=50 nucleus87Rb have been investigated in the (α, α') reaction measuringγγ- and delayedγ-rf-coincidences. A half-life ofT 1/2=6(1) ns was obtained for the level at 1578.1 keV. This experimental result confirms the 9/2+ assignment and the proton 1g9/2 single-particle character of this state. Experimental M2 transition strengths in85,87Rb are compared with predictions of the shell model and the particle-core coupling model.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 2005-2007 
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The technique of intensity dependent photoacoustic probe beam deflection has been applied to the determination of surface damage thresholds. We take advantage of an unambiguous correlation between the degree of laser damage and the energy in the generated acoustic pulse. The high sensitivity of this method, cross checked by measuring scatter losses in reflection, is independent of any surface optical properties. As an example for optical materials, damage thresholds for MgF2 and CaF2 have been determined to be about 1.4 GW/cm2 , and for LiF to be about 0.2 GW/cm2 .
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 10049-10060 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The adsorption dynamics of water on NaCl(100) is studied by molecular dynamics calculations as a function of coverage. We find that, starting from a critical coverage of about 1/2 monolayer, a coupling of the water dipoles sets in and the interaction between the water molecules wins over the interaction between adsorbate and substrate leading via percolation to formation of infinite cluster networks. This effect is confirmed qualitatively by surface sensitive optical second harmonic measurements with well-controlled water exposure. At a coverage of one bilayer, a two-dimensional "ice'' structure is found to be stable. Simulated low-energy electron diffraction (LEED) patterns for this configuration are in excellent agreement with recent observation of a c(4×2) overstructure.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 0021-9991
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Computer Science , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0169-4332
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 0042-207X
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Algorithmica 25 (1999), S. 142-175 
    ISSN: 1432-0541
    Keywords: Key words. Parallel computation, Parallel RAM, Nondeterministic computation, NP, Biomolecular computation, Biotechnology, DNA, Recombinant DNA.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract. This paper is concerned with the development of techniques for massively parallel computation at the molecular scale, which we refer to as molecular parallelism. While this may at first appear to be purely science fiction, Adleman [Ad1] has already employed molecular parallelism in the solution of the Hamiltonian path problem, and successfully tested his techniques in a lab experiment on DNA for a small graph. Lipton [L] showed that finding the satisfying inputs to a Boolean expression of size n can be done in O(n) lab steps using DNA of length O(n log n) base pairs. This recent work by Adleman and Lipton in molecular parallelism considered only the solution of NP search problems, and provided no way of quickly executing lengthy computations by purely molecular means; the number of lab steps depended linearly on the size of the simulated expression. See [Re3] for further recent work on molecular parallelism and see [Re4] for an extensive survey of molecular parallelism. Our goal is to execute lengthy computations quickly by the use of molecular parallelism. We wish to execute these biomolecular computations using short DNA strands by more or less conventional biotechnology engineering techniques within a small number of lab steps. This paper describes techniques for achieving this goal, in the context of well defined abstract models of biomolecular computation. Although our results are of theoretical consequence only, due to the large amount of molecular parallelism (i.e., large test tube volume) required , we believe that our theoretical models and results may be a basis for more practical later work, just as was done in the area of parallel computing. We propose two abstract models of biomolecular computation. The first, the Parallel Associative Memory (PAM) model, is a very high-level model which includes a Parallel Associative Matching (PA-Match) operation, that appears to improve the power of molecular parallelism beyond the operations previously considered by Lipton [L]. We give some simulations of conventional sequential and parallel computational models by our PAM model. Each of the simulations use strings of length O(s) over an alphabet of size O(s) (which correspond to DNA of length O(s log s) base pairs). Using O(s log s) PAM operations that are not PA-Match (or O(s) operations assuming a ligation operation) and t PA-Match operations, we can: 1. simulate a nondeterministic Turing Machine computation with space bound s and time bound 2 O(s) , with t = O(s) , 2. simulate a CREW PRAM with time bound D, with M memory cells, and processor bound P, where here s = O( log (PM)) and t = O(D+s), 3. find the satisfying inputs to a Boolean circuit constructible in s space with n inputs, unbounded fan-out, and depth D, where here t = O(D+s). We also propose a Recombinant DNA (RDNA) model which is a low-level model that allows operations that are abstractions of very well understood recombinant DNA operations and provides a representation, which we call the complex , for the relevant structural properties of DNA. The PA-Match operation for lengthy strings of length s cannot be feasibly implemented by recombinant DNA techniques directly by a single step of complementary pairing in DNA; nevertheless we show this Matching operation can be simulated in the RDNA model with O(s) slowdown by multiple steps of complementary pairing of substrings of length 2 (corresponding to logarithmic length DNA subsequences). Each of the other operations of the PAM model can be executed in our RDNA model, without slowdown. We further show that, with a further O(s)/ log (1/ε) slowdown, the simulations can be done correctly with probability 1/2 even if certain recombinant DNA operations (e.g., Separation) can error with a probability ε. We also observe efficient simulations can be done by PRAMs and thus Turing Machines of our molecular models.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Algorithmica 28 (2000), S. 271-287 
    ISSN: 1432-0541
    Keywords: Key words. Spatial decomposition, Computational geometry, Closest pair, n -Body problem.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract. In this paper we show that if the input points to the geometric closest pair problem are given with limited precision (each coordinate is specified with O( log n) bits), then we can compute the closest pair in O(n log log n) time. We also apply our spatial decomposition technique to the k -nearest neighbor and n -body problems, achieving similar improvements. To make use of the limited precision of the input points, we use a reasonable machine model that allows ``bit shifting'' in constant time—we believe that this model is realistic, and provides an interesting way of beating the Ω(n log n) lower bound that exists for this problem using the more typical algebraic RAM model.
    Type of Medium: Electronic Resource
    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...