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21.
Zusammenfassung Die Struktur der Spiro-(2-oxo- bzw. 2-thionohexahydropyrimidin-4,2-chromane) wird durch Synthese gesichert.
The structure of spiro-2-oxohexahydropyrimidine-4,2-chromanes and spiro-2-thionohexahydropyrimidine-4,2-chromanes is proved by synthesis.相似文献
22.
Alexander Swoboda Lukas Johannes Pfeifenberger Zerina Duhović Moritz Bürgler Dr. Isabel Oroz-Guinea Klara Bangert Florian Weißensteiner Lena Parigger Katharina Ebner Prof. Dr. Anton Glieder Prof. Dr. Wolfgang Kroutil 《Angewandte Chemie (International ed. in English)》2023,62(46):e202312721
Identifying (bio)catalysts displaying high enantio-/stereoselectivity is a fundamental prerequisite for the advancement of asymmetric catalysis. Herein, a high-throughput, stereoselective screening assay is reported that gives information on enantioselectivity, stereopreference and activity as showcased for peroxygenase-catalyzed hydroxylation. The assay is based on spectrophotometric analysis of the simultaneous formation of NAD(P)H from the alcohol dehydrogenase catalyzed enantioselective oxidation of the sec-alcohol product formed in the peroxygenase reaction. The assay was applied to investigate a library comprising 44 unspecific peroxygenases (UPOs) containing 25 UPOs not reported yet. Thereby, previously non-described wild-type UPOs displaying (S)- as well as (R)-stereoselectivity for the hydroxylation of representative model substrates were identified, reaching up to 98 % ee for the (R)- and 94 % ee for the (S)-enantiomer. Homology models with concomitant docking studies indicated the structural reason for the observed complementary stereopreference. 相似文献
23.
J. Swoboda 《Optics and Spectroscopy》2007,103(3):343-348
Given a compact, connected Lie group G with Lie algebra
. We discuss time-optimal control of bilinear systems of the form
where H
d
, H
j
∈
, U ∈ G, and the v
j
act as control variables. The case G = SU(2
n
) has found interesting applications to questions of time-optimal control of spin systems. In this context Eq. (I) describes
the dynamics of an n-particle system with fixed drift Hamiltonian H
d
, which is to be controlled by a number of exterior magnetic fields of variable strength, proportional to the parameters v
j
. The question of interest here is to transfer the system from a given initial state U
0 to a prescribed final state U
1 in least possible time. Denote by
the Lie algebra spanned by H
1, ..., H
m
, and by K the corresponding Lie subgroup of G. After reformulating the optimal control problem for system (I) in terms of an equivalent problem on the homogeneous space
G/K we discuss in detail time-optimal control strategies for system (I) in the case where G/K carries the structure of a Riemannian symmetric space.
The text submitted by the author in English. 相似文献
((I)) |
24.
We prove a coisotropic intersection result and deduce the following: (a) Lower bounds on the displacement energy of a subset of a symplectic manifold, in particular a sharp stable energy-Gromov-width inequality. (b) A stable non-squeezing result for neighborhoods of products of unit spheres. (c) Existence of a “badly squeezable” set in ${\mathbb R^{2n}}$ of Hausdorff dimension at most d, for every n ≥ 2 and d ≥ n. (d) Existence of a stably exotic symplectic form on ${\mathbb R^{2n}}$ , for every n ≥ 2. (e) Non-triviality of a new capacity, which is based on the minimal action of a regular coisotropic submanifold of dimension d. 相似文献
25.
An optical receiver with automatic-gain-control transimpedance amplifier, linear post amplifier and linear line driver suitable for multilevel signals is presented. A large-diameter photodiode (400 μm) with an antireflection coating optimized for red light was integrated. These features enable the presented optical receiver to be a promising plastic optical fiber receiver. An error free (<10−8) 400 Mbit/s data rate over 50 m PMMA-step index plastic optical fiber (1 mm diameter) is achieved with eight-level pulse amplitude modulation (8-PAM). 相似文献
26.
A. Swoboda 《Analytical and bioanalytical chemistry》1897,36(1):518-519
27.
G. L. Kelley J. A. Wiley R. T. Bohm W. C. Wright H. H. Willard Florence Fenwick J. M. Kolthoff O. Tomicek H. Tusker W. Chlopin L. Kaufmann H. D. Newton J. L. Hughes K. Swoboda C. Gallego A. T. Etheridge Hammer Koch A. Fölsner K. Ries W. Singleton A. Kropf G. Misson W. Silberminz E. Roshkowa A. H. Low Julius Meyer O. Kropf S. G. Clarke G. E. F. Lundell J. I. Hoffman H. A. Bright A. Pawletta L. Pisarjewski P. Düllberg und W. M. Hartmann 《Fresenius' Journal of Analytical Chemistry》1932,88(5-6):206-237
Ohne Zusammenfassung 相似文献
28.
Ohne Zusammenfassung 相似文献
29.
Zusammenfassung Es wird gezeigt, daß die Methode der Bromtitration nachB. Smith bei Methylsulfonylphenolen in etwas modifizierter Form gut zur Bestimmung der Zahl freier o- und p-Stellen geeignet ist. Bei Phenylsulfonylphenolen (Hydroxydiphenylsulfonen) ist dieses Verfahren nur beschränkt verwendbar. 相似文献
30.