Library

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
    Electronic Resource
    Electronic Resource
    Asymptotic Behavior of a Set-Statistic (2000)
    Springer
    Discrete & computational geometry 23 (2000), S. 333-365 
    Details
    ISSN: 1432-0444
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract. The existence theorem of Minkowski for a polytope with given facet normals and areas is adapted to a data-analytic context. More precisely, we show that a centered, random point sample arising from an absolutely continuous distribution in R d can be uniquely mapped into such a polytope almost surely. With increasing sample size, the sequence of (scaled) polytopes converges almost surely to a limiting convex body that is associated with the underlying distribution. An accompanying central limit theorem is proved using methods from the theory of empirical processes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00009504
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Electrical conductivity of highly concentrated electrolytes near the critical consolute point: A study of tetra-n-butylammonium picrate in alcohols of moderate dielectric constant (2001)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 115 (2001), S. 9871-9882 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The electrical conductivity of highly concentrated solutions of tetra-n-butylammonium picrate (TBAP) in 1-dodecanol (dielectric constant cursive-epsilon=4.6) and 1,4-butanediol (cursive-epsilon=25.9), and in mixtures of both alcohols, is measured in an extended temperature range (approximate)10−5〈τ〈(approximate)10−1, where τ=(T−Tc)/Tc is the reduced temperature with Tc, the critical temperature. The electrical conductivity Λ(T) obeys the Vogel–Fulcher–Tammann (VFT) law for the temperatures far from the critical one. In the temperature range τ〈10−2 a systematic deviation of the electrical conductivity from the regular VFT behavior is observed. This deviation is attributed to a critical anomaly. At the critical point the amplitude of the critical anomaly is finite with a value which varies between (approximate)0.4 and (approximate)2.7% of Λ(Tc), depending on the solvent. The (1−α) critical exponent describes well the conductivity anomaly, α being the exponent of the specific heat anomaly at constant pressure. The value of the Walden product (Λeqvη), with Λeqv, the equivalent conductivity and η, the shear viscosity, allows the degree of dissociation αdiss of TBAP to be determined at the critical point. αdiss becomes larger for increasing values of cursive-epsilon: for TBAP in 1-dodecanol αdiss(approximate)0.25 and in 1,4-butanediol αdiss(approximate)0.73. When the degree of dissociation of the salt is accounted for the Debye screening length is found almost independent on cursive-epsilon. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1415458
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Small-angle neutron scattering from supercritical heavy water at off-critical densities (2001)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 115 (2001), S. 4660-4669 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We report the results of small-angle neutron scattering measurements performed on supercritical heavy water at wave-number transfers between 0.07 and 0.36 Å−1. The data were collected along five different isochores at temperatures about 1.15, 2.20, and 5.50 °C higher than the measured critical temperature. The density, ρ, was in the range (ρc−0.062)〈ρ〈(ρc+0.082) g cm−3, where ρc is the critical density. The shape of the scattering spectra is represented by the expression previously used for those measured along the critical isochore [Bonetti et al., J. Chem. Phys. 112, 268 (2000)]. The temperature and density dependencies of the isothermal compressibility and the correlation length can be reasonably described using a parametric representation of the thermodynamic space and corrections to scaling that include odd terms to account for the asymmetry of the system. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1392362
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Small-angle neutron scattering from heavy water in the vicinity of the critical point (2000)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 112 (2000), S. 268-274 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Small-angle neutron scattering spectra from supercritical heavy water were recorded along a near-critical isochore at temperatures between (Tc,exp+1.63 K) and (Tc,exp+22.02 K), Tc,exp being the experimental critical temperature. At low values of the wave number transfer q, the scattered intensity shows a pronounced increase due to the divergence of density fluctuations at the critical point. In the studied q range, from 0.07 to 0.36 Å−1, all the spectra can be accurately described by the Fisher–Langer correlation function provided that a multiplicative additional term describing short-range correlations between water molecules is taken into account. The value found for the amplitude of the critical correlation length is ξ0=(1.36±0.06) Å, in fair agreement with the value predicted by the two-scale hypothesis. © 2000 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.480633
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Measurement and analysis of the scattered light in the critical ionic solution of ethylammonium nitrate in n-octanol (1997)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 107 (1997), S. 550-561 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: New measurements of the static light scattering as a function of temperature in the critical ionic mixture ethylammonium nitrate+n-octanol are reported. A basic analysis indicates that the system would belong to the Ising universality class. Attempts at characterizing the corrections to the Ising scaling are made. The conclusion is that, within the experimental uncertainty, the system shows a practically pure Ising behavior in the range 10−4≤(T−Tc)/Tc≤2×10−2 with, perhaps, a slight trend to display negative corrections (i.e., opposite to a partial crossover toward the classical behavior). © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.474415
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    The viscosity anomaly near the critical consolute point of the ionic ethylammonium nitrate-n-octanol mixture (1996)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 3111-3119 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Measurements of the temperature dependence of the shear viscosity of the ionic binary mixture ethylammonium nitrate in n-octanol near the critical consolute point are reported. The kinematic viscosity is measured with a capillary viscometer in the range of reduced temperature 3×10−5≤t=(T−Tc)/Tc≤6.2×10−2. The temperature dependence of the density is measured by a volume dilatometer. No critical density anomaly is observed within the temperature range 5×10−4≤t≤4×10−2. Shear viscosity data are consistent with a power law divergence η=η0 (Qξ0)−y/νt−yF predicted by the mode-coupling and the dynamic renormalization group theories. The value of the critical exponent y agrees with the theoretical value y=0.032 when the critical temperature Tc is fixed at the experimental value. When Tc is set as a free parameter the fits give 0.0385≤y≤0.0438, depending on the forms chosen for the background viscosity η0 and the crossover function F. Estimation of the wave number Q is found in agreement with data obtained for neutral fluids. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.471076
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    A very precisely regulated compact thermostat for small-angle neutron scattering (1997)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 68 (1997), S. 4163-4168 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We have built a simple two-stage thermostat for measuring small-angle neutron scattering from liquids or solids in the vicinity of a phase transition. The thermostat was tested between 20 and 75 °C. The long-term temperature stability varies within ±0.2 and ±0.5 mK, depending on the set-point temperature. Positive and negative temperature steps of 0.5 mK and more can be obtained without overshoot. Small-angle neutron spectra from a binary ionic mixture in the critical domain are also reported. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1148362
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A small-angle neutron scattering cell for the study of supercritical fluids at elevated pressure and high temperature: A study of heavy water (1999)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 70 (1999), S. 4015-4019 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The main characteristics of a cell optimized for small-angle neutron scattering experiments on supercritical fluids are presented. The cell operates satisfactorily at pressures up to 300 bar at 400 °C and 750 bar at 90 °C. It has large apertures sealed by thick synthetic sapphire windows. The maximum forward scattering angle is 16° and the sample path length is 5.1 mm. It has been used to study scattering from supercritical heavy water close to its critical point at wave number transfers up to 0.34 Å−1. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1150027
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Rhinopharyngoscopy, computed tomography and magnetic resonance imaging (1997)
    Oxford, UK : Blackwell Publishing Ltd
    Allergy 52 (1997), S. 0 
    Details
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Rhinitis is defined as nasal congestion, sneezing, itching and rhinorrhoea, recently classified as allergic, infective, structural or “other”. The increasing employment of flexible rhynolaringoscopy may represent one of the most useful diagnostic tools in the complex differential diagnosis between allergic and nonallergic rhinitis. Furthermore, chronic allergic rhinitis, with secondary impairment of mucociliary clearance and the plethora of frequent anatomical variations, especially in the ostiomeatal complex, appear to predispose the patient to recurrent rhinosinusitis. In the last two decades, a better understanding of mucociliary clearance of nasal cavity and paranasal sinuses has shifted the attention from the maxillary sinuses to the area of the antherior ethmoid sinuses. Plain fiim radiographic examination, the historical standard, due to its inability to individualize ethmoid and sphenoid disease, is being rapidly supplanted by computed tomography and magnetic resonance imaging in the diagnosis of rhinosinusitis In allergic and non-allergic rhinitis the diagnostic role of magnetic resonance imaging and computed tomography is still under debate. Computed tomography and magnetic resonance imaging are more efficient in demonstrating the bone wall, mucosal layer and sinus content than classical and computerized radiology; they have a higher diagnostic performance index in spite of a higher cost and, for computed tomography, a higher radiation dose.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1398-9995.1997.tb04802.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    99mTc HM-PAO brain perfusion SPECT in brain death (1995)
    Springer
    Neuroradiology 37 (1995), S. 365-369 
    Details
    ISSN: 1432-1920
    Keywords: Key words Brain death ; Cerebral blood flow ; HM-PAO SPECT
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Diagnosis of brain death must be certain to allow discontinuation of artificial ventilation and organ transplantation. Brain death is present when all functions of the brain stem have irreversibly ceased. Clinical and electrophysiological criteria may be misinterpreted due to drug intoxication, hypothermia or technical artefacts. Thus, if clinical assessment is suboptimal, reliable early confirmatory tests may be required for demonstrating absence of intracranial blood flow. We have easily carried out and interpreted 99mTc HM-PAO SPECT in a consecutive series of 40 comatose patients with brain damage, without discontinuing therapy. Brain death was diagnosed in 7 patients, by recognising absence of brain perfusion, as shown by no intracranial radionuclide uptake. In patients in whom perfusion was seen on brain scans, HM-PAO SPECT improved assessment of the extent of injury, which in general was larger than suggested by CT.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00588013
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...