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41.
W. Scheele R. E. Liesegang Knoll H. -J. Schumacher E. Wöhlisch J. Reitstötter 《Colloid and polymer science》1942,101(1):109-111
Ohne Zusammenfassung 相似文献
42.
43.
Inhomogeneous Markov chains are a relevant framework for analysing event histories. The fundamental estimator in the presence
of incompletely observed data is the Nelson-Aalen estimator of the multivariate cumulative hazards. It may be summarised in
terms of probability estimates via the empirical transition matrix. The empirical transition matrix has only slowly entered
applications, one reason being previous lack of software. In a number of applications, further summary measures are desired.
We illustrate how they may be computed from the empirical transition matrix and why bootstrapping their variance works. In
contrast, computing such summaries outside the present framework has typically led to biased results. As an example, we consider
in more detail hospital stay following infectious complication. This summary quantity is often considered by clinical decision
makers, but reliable estimates require modelling the timing of infection as in the present set-up. In this context, we also
derive new summary measures that further distinguish between patients discharged and patients deceased. 相似文献
44.
Katrin Schumacher 《Czechoslovak Mathematical Journal》2009,59(3):637-648
Given a domain Ω of class C
k,1, k ∈ ℕ, we construct a chart that maps normals to the boundary of the half space to normals to the boundary of in the sense
that (∂/∂x
n
)α(x′, 0) = − N(x′) and that still is of class C
k,1. As an application we prove the existence of a continuous extension operator for all normal derivatives of order 0 to k on domains of class C
k,1. The construction of this operator is performed in weighted function spaces where the weight function is taken from the class
of Muckenhoupt weights. 相似文献
45.
46.
The defect formation in the bcc metals W and Mo above annealing stage III and the influence of rare gases on this process
were investigated by means of the perturbed angular correlation technique using111In as radioactive probe. In both metals a relatively high electric field gradient (EFG) could be observed at the indium site,
characterized by the quadrupole interaction frequencies υQ=263 MHz, ν=0 and υQ=220 MHz, ν≈0.15 for W and Mo, respectively. The observations are assigned to the growth of threedimensional vacancy clusters
at the probe atoms with the indium atoms situated in the inner surface of this cavities, thus experiencing the corresponding
surface EFG. 相似文献
47.
J. Ahrens S. Altieri J. R. M. Annand H. -J. Arends R. Beck A. Braghieri N. d'Hose H. Dutz S. Goertz P. Grabmayr S. Hasegawa E. Heid H. Holvoet L. Van Hoorebeke N. Horikawa T. Iwata O. Jahn P. Jennewein R. Kondratiev J. Krimmer M. Lang B. Lannoy K. Livingston J. C. McGeorge W. Meyer A. Panzeri P. Pedroni T. Pinelli I. Preobrajenski G. Reicherz G. Rosner M. Rost T. Rostomyan D. Ryckbosch M. Schumacher B. Seitz G. Tamas A. Thomas R. van de Vyver Th. Walcher F. Zapadtka 《The European Physical Journal A - Hadrons and Nuclei》2005,26(1):135-140
The G asymmetry of the γp↦Nπ reaction has been measured for the first time for Eγ = 340±14 MeV. This observable, for which very scarce published data exist, plays an important role to disentangle the contributions
of the various nucleon resonances. The experiment, performed at the Mainz microtron MAMI, used a 4π-detector system, a linearly
polarized, tagged photon beam, and a longitudinally polarized proton target. 相似文献
48.
Dendritic Glycopolymer as Drug Delivery System for Proteasome Inhibitor Bortezomib in a Calcium Phosphate Bone Cement: First Steps Toward a Local Therapy of Osteolytic Bone Lesions
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49.
50.
Mechanistic Insights into the Post‐Cyclization Isomerization in Gold‐Catalyzed 7‐exo‐dig‐Hydroarylations
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M. Sc. Daniel Pflästerer Sören Schumacher Dr. Matthias Rudolph Prof. Dr. A. Stephen K. Hashmi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11585-11589
The subsequent double‐bond isomerization in the synthesis of dibenzocycloheptenes and their heteroaromatic analogues was investigated. In the case of biphenyls, a basic additive completely prevented an isomerization to the thermodynamic product. With electron‐rich intramolecular heteroaromatic nucleophiles, the isomerization was still observed, but the kinetic product can be obtained by careful control of the reaction times in most cases. Mechanistic studies demonstrated that a slow isomerization is also possible with the gold catalyst at elevated temperatures, but much faster isomerization rates were observed with acidic additives. An observed initiation period for the gold‐catalyzed isomerization indicates that not the homogenous catalyst, but a decomposition product of it may be the catalytically active species. 相似文献