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The Direct Thiation of Pyrimidinol Derivatives.
Chemical and Pharmaceutical Bulletin, 1963 The replacement of 4-hydroxyl group of aminopyrimidinols by sulfhydryl in one step, through the action of phosphorus pentasulfide in triethylamine or 3-picoline. 5-Acylamino-6-amino-4-pyrimidinols were treated with phosphorus pentasulfide in pyridine, to yield thiazolo [5, 4-d] pyrimidine and 6-purinethiol compounds.
Ueda, Takeo +2 more
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Directed Carbozincation Reactions of Cyclopropene Derivatives [PDF]
Journal of the American Chemical Society, 2009 A diastereoselective procedure has been developed for the Cu-catalyzed addition of diorganozinc reagents to cyclopropene derivatives. Ester and oxazolidinone functions direct the addition of a variety of organozinc reagents with excellent facial selectivity.
Vinod, Tarwade +3 more
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On generalized derivatives for C1,1 vector optimization problems
Journal of Applied Mathematics, 2003 We introduce generalized definitions of Peano and Riemann directional derivatives in order to obtain second-order optimality conditions for vector optimization problems involving C1,1 data.
Davide La Torre
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The Directional Derivative in General Quantum Calculus
Symmetry, 2022 In this paper, we define the β-partial derivative as well as the β-directional derivative of a multi-variable function based on the β-difference operator, Dβ, which is defined by Dβf(t)=f(β(t))−f(t)/β(t)−t, where β is a strictly increasing continuous function. Some properties are proved. Furthermore, the β-gradient vector and the β-gradient directional
Avin O. Karim +2 more
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Exponential Stabilizability of Switched Systems with Polytopic Uncertainties
Journal of Applied Mathematics, 2012 The exponential stabilizability of switched nonlinear systems with polytopic uncertainties is explored by employing the methods of nonsmooth analysis and the minimum quadratic Lyapunov function.
Xia Zhang, Zun-Quan Xia, Yan Gao
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Identification of Aircraft Lateral-Directional Derivatives
, 2021 The application of neural networks combined with partial differentiation of the neural outputs is discussed in this chapter to estimate lateral-directional flight stability and control derivatives from flight data.
Majeed Mohamed +3 more
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Saddles as rotational locks within shape-assisted self-assembled nanosheets
Nature Communications, 2023 Two-dimensional (2D) materials are a key target for many applications in the modern day. Self-assembly is one approach that can bring us closer to this goal, which usually relies upon strong, directional interactions instead of covalent bonds.
Joseph F. Woods +10 more
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Direct Corticospinal Control of Force Derivative [PDF]
The Journal of Neuroscience, 2011 During simultaneous generation of static and dynamic forces, motor cortical signals only predict the dynamic components, suggesting a key role in the coding of force changes. However, such a role is obscured by uncertainties regarding the representation of dynamic force signals in corticospinal outputs.
Oscar, Soto, Didier, Cros
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Coupled bidirectional flow for adaptive image interpolation
Tongxin xuebao, 2007 An adaptive coupled bidirectional flow process was presenfed,where an inverse diffusion was performed to enhance edges along the normal directions to the isophote lines（edges）,while a normal diffusion was done to remove ar-tifacts（“jaggies”） along the ...
FU Shu-jun 1 +3 more
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Discrete spherical means of directional derivatives and Veronese maps [PDF]
, 2011 We describe and study geometric properties of discrete circular and spherical means of directional derivatives of functions, as well as discrete approximations of higher order differential operators.
Alexander Belyaev +8 more
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