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111.
New historical aspects of the classification, by Cayley and Cremona, of ruled quartic surfaces and the relation to string
models and plaster models are presented. In a ‘modern’ treatment of the classification of ruled quartic surfaces the classical
one is corrected and completed. The string models of Series XIII of some ruled quartic surfaces (manufactured by L. Brill
and by M. Schilling) are based on a result of Rohn concerning curves in
\mathbbP1×\mathbbP1{\mathbb{P}^1\times \mathbb{P}^1} of bi-degree (2, 2). This is given here a conceptional proof. 相似文献
112.
We consider the three-dimensional motion of a self-propelled deformable structure into a viscous incompressible fluid. The
deformation of the solid is given whereas its position is unknown. Such a system could model the propulsion of fish-like swimmers.
The equations of motion of the fluid are the Navier-Stokes equations and the equations for the structure are deduced from
Newton’s laws. The corresponding system is a free boundary problem and the main result of the paper is the existence of weak
solutions for this problem. 相似文献
113.
We address the global persistence of analyticity and Gevrey-class regularity of solutions to the two and three-dimensional
visco-elastic second-grade fluid equations. We obtain an explicit novel lower bound on the radius of analyticity of the solutions
that does not vanish as t → ∞, and which is independent of the Rivlin–Ericksen material parameter α. Applications to the damped incompressible Euler equations are also given. 相似文献
114.
Marius Stroe 《Molecular physics》2013,111(12):1617-1625
115.
Dr. Eduard Baal Marius Klein Dr. Klaus Harms Prof. Dr. Jörg Sundermeyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12610-12618
The synthesis of 2,9-diaza-1,3,8,10-tetratriflato-dibenzoperylene (DDP 3 a ) and corresponding 2,9-dimethyl-1,3,8,10-tetratriflato-dibenzoperylene (DBP 3 b ) has been developed at multigram scale via reduction of one of the industrially most important high-performance dyes, perylene-3,4,9,10-tetracarboxylic diimide (PTCDI), and of the corresponding dihydroxy peropyrenequinone precursor. The focus of this paper is on the reactivity pattern of 3 a as key intermediate towards highly functionalized 2,9-diazadibenzopyrelenes (DDPs) obtained via catalytic substitution of four triflate by aryl, heteroaryl, alkynyl, aminyl, and O-phosphanyl substituents. The influence of electron-donating substituents (OSiMe3, OPt-Bu2, N-piperidinyl), electron-withdrawing (OTf, 3,5-bis-trifluoromethyl-phenyl), and of electron-rich π-conjugated (2-thienyl, 4-tert-butylphenyl, trimethylsilyl-ethynyl) substituents on optoelectronic and structural properties of these functionalized DDPs has been investigated via XRD analyses, UV/Vis, PL spectroscopy, and by electroanalytical CV. These results were correlated to results of DFT and TD-DFT calculations. Thus, functionalized DPPs with easily tunable HOMO and LUMO energies and gap became available via a new and reliable synthetic strategy starting from readily available PTCDI. 相似文献
116.
Hu Xing Yiting Zhang Markus Krmer Ann-Kathrin Kissmann Marius Henkel Tanja Weil Uwe Knippschild Frank Rosenau 《Molecules (Basel, Switzerland)》2022,27(17)
Recent studies have demonstrated that changes in the abundance of the intestinal bacterium Blautia producta, a potential probiotic, are closely associated with the development of various diseases such as obesity, diabetes, some neurodegenerative diseases, and certain cancers. However, there is still a lack of an effective method to detect the abundance of B. producta in the gut rapidly. Especially, DNA aptamers are now widely used as biometric components for medical testing due to their unique characteristics, including high chemical stability, low production cost, ease of chemical modification, low immunogenicity, and fast reproducibility. We successfully obtained a high-affinity nucleic acid aptamer library (B.p-R14) after 14 SELEX rounds, which efficiently discriminates B. producta in different analysis techniques including fluorometric suspension assays or fluorescence microscopy from other major gut bacteria in complex mixtures and even in human stool samples. These preliminary findings will be the basis towards aptamer-based biosensing applications for the fast and reliable monitoring of B. producta in the human gut microbiome. 相似文献
117.
József Kaizer József Pap Gábor Speier Marius Réglier Michel Giorgi 《Transition Metal Chemistry》2004,29(6):630-633
The preparation, spectroscopic properties, and crystal structure of [Cu(ind)(mco)] [ind is the anion of 1,3-bis(2-pyridylimino)isoindoline and mco is the anion of 3-hydroxy-(4H)-benzopyran-4-one] are reported. The complex exhibits a distorted square pyramidal geometry. The oxygenation of the title compound results in oxidative cleavage of the heterocyclic ring to give the (acetylsalicylato)copper(II) complex [Cu(asp)(ind)] (asp is the anion of acetylsalicylic acid) and CO as primary products, which reaction resembles the enzymatic reaction of quercetinase. 相似文献
118.
Christian Schreiner Dipl.‐Chem. Marius Amereller Dipl.‐Chem. Heiner J. Gores Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(10):2270-2272
Chloride avoided! A new chloride‐free method to synthesise ionic liquids (ILs) with mixed borate anions, starting from tetrafluoroborate compounds, has been developed and a number of examples including some new ILs are presented (see scheme; [CAT]+=cation). It is widely applicable and allows access to mixed borates with various types of ligands in a straightforward manner.
119.
In this paper we consider operators of the form H=λ(-i∇), with λ analytic in a strip and with some specific growth conditions at infinity, and prove Hardy type estimates in L
2(ℝ
n
) with exponential weights. In fact we extend our previous results [19] from bounded analytic functions on a strip to analytic
functions with polynomial growth in that strip. 相似文献