An effective synthesis of the hitherto unknown 1-imidoalkylphosphonium salts has been developed in the reported study. The crucial step in the method included the decarboxylative α-methoxylation of N-phthaloyl- or N-succinylamino acids to the corresponding N-(1-methoxyalkyl)imides, followed by the displacement of the methoxy group by the triarylphosphonium group through melting of the imide der...

The interaction of structurally different carotenoids with a membrane molecular model was examined by X-ray diffraction. The selected compounds were beta-carotene, lycopene, lutein, violaxanthin, zeaxanthin, and additionally carotane, a fully saturated derivative of beta-carotene. They present similarities and differences in their rigidity, the presence of terminal ionone rings and hydroxy and ...

The chemical analysis of gamma-hydroxybutyric acid (GHB) in most forensic laboratories is complicated by the highly polar nature of the GHB molecule, which makes it unsuitable for direct analysis by gas chromatography (GC). Consequently, a popular analytical approach is to convert GHB into the corresponding lactone or a derivative compound that is then identified by mass spectrometry employed i...

Inspired by the previous work of Aicardi et al.[1] a path following controller for underactuated planar vehicles is designed by adopting a polar-like kinematic model of the system. The solution proposed does not generally guarantee null asymptotic path following error, but only its boundedness below an adjustable upper threshold. However, knowledge of the path curvature is not necessary, thus r...

buprenorphine is a partial mu agonist and kappa antagonist which is used for the treatment of pain and opioid addiction. a mixture of buprenorphine hydrochloride and naloxone hydrochloride has been approved for the treatment of opioid dependence.in this study a third order derivative spectrophotometric method based on zero-crossing technique has been used for the simultaneous determination of b...

This is a pioneering work, introducing special class of complex numbers, wherein their absolute values and arguments given in Polar coordinate system are integers, which when considered within the plane, constitute Unicentered Radial Lattice similarly for quaternions Euclidean R2 R3 Spaces. The corresponding Optimization Problems introduced as well.

Starting from second-order conditions for C scalar unconstrained optimization problems described in terms of the second-order Dini directional derivative, we pose the problem, whether similar conditions for C vector optimization problems can be derived. We define second-order Dini directional derivatives for vector functions and apply them to formulate such conditions as a Conjecture. The proof...

The computational cost of conventional lter methods for junction characterization is very high. This burden can be attenuated by using steerable lters. However, in order to achieve a high orientational selectivity to characterize complex junctions a large number of basis lters is necessary. From this results a yet too high computational eeort for steerable lters. In this paper we present a new ...