Lipids from <Emphasis Type="Italic">Crambe amabilis</Emphasis> and <Emphasis Type="Italic">C. kotschyana</Emphasis> seeds grown with saline irrigation water

Lipids from Crambe amabilis Butk. et Majlun and C. kotschyana Boiss. grown in the open in Uzbekistan in soil imported from the Aral Sea region were studied. It was found that the seed oil content decreased with increasing salinity of irrigation water with EC 1.5 up to 9.0 dS/m. The content of polar lipids increased. The content of unsaturated acids from C. amabilis neutral lipids was 94.74–97.46%; C. kotschyana, 95.76– 96.78%.     

Reactivity and Structure of Difluorophosphine Compounds and Their Platinum Complexes

Abstract

Various novel organodifluorophosphines involving aromatic and aliphatic substituents were prepared and used as ligands in reactions with (COD)PtCl₂ or K₂PtCl₄; complexes of the type cis-dichlorobis(organodifluorophos-phine)platinum(II) or tetrakis (organodifluorophosphine)platinum(O) were formed. The ³¹P-n.m.r. data of these compounds were correlated with Pt-P bond lengths found from X-ray diffraction studies. The hydrolysis of RPF₂ and Pt(RPF₂)₄ with water leads to the formation of RP(F)(O)(H) or [RP(F)(OH)]₂[RP((F)]₂Pt. Both products were characterized by n.m.r. spectra and by X-ray structure determinations.     

Field-dependent ion transport in disordered solid electrolytes

We have carried out experimental and theoretical studies of the electric field-dependent ion transport in disordered materials and in disordered potential landscapes, respectively. In our experiments, we work in an electric field range up to 100 kV cm(-1), which is characterised by a weak nonlinear response of the mobile ions. We detect remarkable differences between different ion-conducting glasses regarding the temperature dependence of the nonlinear response. Theoretically, we study one-dimensional hopping models and continuous disordered potential models, respectively. When comparing theoretical and experimental data, we find both analogies and discrepancies.     

An adaptive boundary element method for the exterior Stokes problem in three dimensions

^** Email: vjervin{at}clemson.edu^*** Email: norbert.heuer{at}brunel.ac.uk We present an adaptive refinement strategy for the h-versionof the boundary element method with weakly singular operatorson surfaces. The model problem deals with the exterior Stokesproblem, and thus considers vector functions. Our error indicatorsare computed by local projections onto 1D subspaces definedby mesh refinement. These indicators measure the error separatelyfor the vector components and allow for component-independentadaption. Assuming a saturation condition, the indicators giverise to an efficient and reliable error estimator. Also we describehow to deal with meshes containing quadrilaterals which arenot shape regular. The theoretical results are underlined bynumerical experiments. To justify the saturation assumption,in the Appendix we prove optimal lower a priori error estimatesfor edge singularities on uniform and graded meshes.     

Nonlinear vibrations of elastic beams with external general visco-elastic devices

Vibration damping for slender beams is achieved by applying devices at external points. The latter consist of general single visco-elastic springpot elements. An approximate nonlinear boundary value problem is found in frequency domain that holds for moderately large vibrations or for linear beams with external nonlinear devices, both in the vicinity of primary resonances. The interaction force of a so-called springpot element is expressed as a sum of two separate forces: the first develops due to the external loading function at the device location, and the second contribution arises due to an imposed time-harmonic support excitation with no other external forces acting on the structure. Finally the nonlinear frequency response function follows from a (nonlinear) algebraic equation where the influence of the springpot element appears as isolated parameter. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

The boundary element method with Lagrangian multipliers

On open surfaces, the energy space of hypersingular operators is a fractional order Sobolev space of order 1/2 with homogeneous Dirichlet boundary condition (along the boundary curve of the surface) in a weak sense. We introduce a boundary element Galerkin method where this boundary condition is incorporated via the use of a Lagrangian multiplier. We prove the quasi‐optimal convergence of this method (it is slightly inferior to the standard conforming method) and underline the theory by a numerical experiment. The approach presented in this article is not meant to be a competitive alternative to the conforming method but rather the basis for nonconforming techniques like the mortar method, to be developed. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009     

pH-Triggered Recovery of Organic Polymer Photocatalytic Particles for the Production of High Value Compounds and Enhanced Recyclability

Pseudo-homogeneous polymeric photocatalysts are an emerging class of highly efficient and tunable photocatalytic materials, where the photocatalytic centers are easily accessible. The creation of highly efficient photocatalytic materials that can be rapidly separated and recovered is one of the critical challenges in photocatalytic chemistry. Here, we describe pH-responsive photocatalytic nanoparticles that are active and well-dispersed under acidic conditions but aggregate instantly upon elevation of pH, enabling easy recovery. These responsive photocatalytic polymers can be used in various photocatalytic transformations, including Cr^VI reduction and photoredox alkylation of indole derivative. Notably, the cationic nature of the photocatalyst accelerates reaction rate of an anionic substrate compared to uncharged species. These photocatalytic particles could be readily recycled allowing multiple successive photocatalytic reactions with no clear loss in activity.     

Spectral properties of hemicyanine dye in confinement by helical amylose

Hemicyanine dye structure is modified with a C₁₆-alkyl chain to amino-head and a C_1, C₈ or C₁₆ alkyl to pyridinium-tail. Spectral properties of the dyes in supramolecular inclusion complexation with amylose are studied in order to assess the mono-functional polarity sensing activity of the pyridinium cations in DMSO-H₂O mixtures. Inclusion complexation brings the γ_max of C₁₆DASPC₁ dye to a blue-shift (relative to that of the free dye state) while that of C₁₆DASP(C₈ and C₁₆) dyes remains almost unchanged.