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71.
A. Mayrhofer Ch. Schneider A. Wasitzky F. Vieböck N. Berend S. Raszeja L. Wacker F. W. Sunderman P. Williams A. Born E. Obermer und R. Milton 《Fresenius' Journal of Analytical Chemistry》1934,99(3-4):154-160
Ohne Zusammenfassung 相似文献
72.
Leonh Wacker und Bölsing 《Fresenius' Journal of Analytical Chemistry》1903,42(8):524-525
Ohne Zusammenfassung 相似文献
73.
Eine Mikroarray‐Strategie zur Untersuchung der Substratspezifitäten von Protein‐Tyrosin‐Phosphatasen
74.
The formation of electric field domains in doped semiconductor superlattices is described within a microscopic model. Due to the presence of impurity bands in low-doped samples the current–voltage characteristic is essentially different compared to medium-doped samples. 相似文献
75.
Sabrina Loschonsky Tobias Wacker Simon Waltzer Pier Paolo Giovannini Michael J. McLeish Susana L. A. Andrade Michael Müller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(52):14630-14634
ThDP‐dependent cyclohexane‐1,2‐dione hydrolase (CDH) catalyzes the C C bond cleavage of cyclohexane‐1,2‐dione to 6‐oxohexanoate, and the asymmetric benzoin condensation between benzaldehyde and pyruvate. One of the two reactivities of CDH was selectively knocked down by mutation experiments. CDH‐H28A is much less able to catalyze the C C bond formation, while the ability for C C bond cleavage is still intact. The double variant CDH‐H28A/N484A shows the opposite behavior and catalyzes the addition of pyruvate to cyclohexane‐1,2‐dione, resulting in the formation of a tertiary alcohol. Several acyloins of tertiary alcohols are formed with 54–94 % enantiomeric excess. In addition to pyruvate, methyl pyruvate and butane‐2,3‐dione are alternative donor substrates for C C bond formation. Thus, the very rare aldehyde–ketone cross‐benzoin reaction has been solved by design of an enzyme variant. 相似文献
76.
Benjamin Wacker 《Mathematical Methods in the Applied Sciences》2019,42(13):4554-4569
We consider the time‐dependent magnetic induction model where the sought magnetic field interacts with a prescribed velocity field. This coupling results in an additional force term and time dependence in Maxwell's equation. We propose two different magnetic diffusivity stabilized continuous nodal‐based finite element methods for this problem. The first formulation simply adds artificial magnetic diffusivity to the partial differential equation, whereas the second one uses a local projected magnetic diffusivity as stabilization. We describe those methods and analyze them semi‐discretized in space to get bounds on stabilization parameters where we distinguish equal‐order elements and Taylor‐Hood elements. Different numerical experiments are performed to illustrate our theoretical findings. 相似文献
77.
Sandstede JJ Pabst T Wacker C Wiesmann F Hoffmann V Beer M Kenn W Bauer W Hahn D 《Magnetic resonance imaging》2001,19(2):201-205
Demonstration of the initial results of breath-hold 3D MR coronary angiography with patients using a new intravascular contrast agent (feruglose). Contrast-enhanced 3D MR-coronary angiography was performed in 5 patients with coronary artery disease after administration of feruglose in three different doses (0.5 (n = 3), 2, 5 mg Fe/kg body weight for each patient). MR coronary angiography was performed with an ECG-triggered 3D-FLASH-sequence during breath-hold at 1.5 T (TR 6.8 ms, TE 2.5 ms, flip-angle 30 degrees ). To reduce data acquisition time, only the two anterior elements of the phased-array body coil were activated. The data acquisition window within the cardiac cycle ranged between 217-326 ms depending on the matrix. Signal-to-noise (SNR) and contrast-to-noise ratios (CNR) of the coronary arteries were analyzed, and the results for the detection of coronary artery stenoses were compared with those obtained by conventional coronary angiography. SNR and CNR revealed an improved image quality at a dose of 2 mg Fe/kg compared with the lower dose, but no further improvement was obtained by rising the dose to 5 mg Fe/kg. Except for the left circumflex artery of one patient, at minimum the proximal parts of all four main coronary arteries could be imaged for all patients. Within the visible parts of the coronary arteries, six of eight significant coronary stenoses were identified correctly. Imaging of the proximal parts of the coronary arteries including detection of stenoses is possible during breath-hold using an intravascular contrast agent. 相似文献
78.
79.
M. Feilmeier P. Gessner H. J. Wacker 《Mathematical Methods of Operations Research》1970,14(1):263-275
Zusammenfassung Es wird eine große Klasse von linearen Kontrollproblemen unter einem einheitlichen Gesichtspunkt betrachtet. Wir geben hierfür ein allgemeines Lösungsprinzip an. Wichtige Spezialfälle werden näher erläutert und die resultierenden Rechenvorschriften angegeben.
Vorgel. v.:J. Heinhold 相似文献
Summary The paper treats a vast number of linear control problems under one unifying aspect. A general principle of solution as well as a certain number of interesting special cases together with their computational algorithms will be given.
Vorgel. v.:J. Heinhold 相似文献
80.
Franziska Kü hnemund Markus Wacker 《Proceedings of the American Mathematical Society》2001,129(12):3569-3582
In this paper we investigate commutator conditions for two strongly continuous semigroups and on a Banach space implying the convergence of the Lie-Trotter products . The results are then applied to various examples and, in particular, to the Ornstein-Uhlenbeck operator.