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Nanostructured non-lamellar lipid particles are widely studied in various fields of application, although their self-assembled structure is sensitive to internal and external conditions, which may limit their applicability. The aim of this study was to overcome these limitations and create particles with non-lamellar nanostructures which are stable over time, upon drying and heating. This was achieved by the combination of two approaches: self-assembly of lipids and polymerization of alkoxysilanes. Precursors containing one or two unsaturated acyl chains were functionalized with trialkoxysilane headgroups. Contrarily to previous studies, the use of unsaturated acyl chains led to the formation of hybrid particles with non-lamellar internal nanostructures. These particles showed a sponge or a hexagonal arrangement and were named spongosomes and hexosomes. Due to the covalent linking of the precursors, durable structures were obtained. The particles were stable for at least several months and maintained their nanostructures even when they were dried or exposed to high temperatures. The inorganic functionalization of lipids enabled the fixation of the self-assembled nanostructures.

In the past, the electrochemical properties of organosilicon compounds were investigated for both fundamental reasons and synthesis purposes. Little is, however, known about the electrochemical behaviour of hydrogen-bearing arylsilanes. Here, we throw light on the electrochemical properties of 11 arylsilanes compounds, 2 of them synthesized for the first time. The oxidation potentials are found to depend on both the nature and number of the aryl groups. Based on these findings it was possible to establish some variation trends that match the expected structure–property correlations. Furthermore, we present first insights into the electrochemical reaction kinetics behind and identify several soluble electrochemical oxidation products. Keywords: Arylsilanes, Synthesis, Oxidation potential, Thermodynamics, Kinetics, Fluorination

Computation of eigenvalues as well as corresponding eigenvectors of a time-varying matrix (i.e., with time-dependent elements) is attractive. A continuous Zhang neural network (ZNN) model is developed for computing the eigenvalues and corresponding eigenvectors of a time-varying real symmetric matrix. The global convergence to the theoretical eigenvalues and corresponding eigenvectors is proved by theoretical analysis. Meanwhile, the robustness analysis is also presented. In addition, the ZNN model is a dynamic system in essence, which indicates the potential practical implementations and applications. Moreover, numerical experiments are conducted in this paper, and the results verify the effectiveness of the ZNN model. Besides, an extensional ZNN model is discussed in the Appendix.

The optimization of the thermal treatment of cationic starch in the paper industry offers the opportunity to reduce the energy consumption of this process. Four different industrially relevant cationic starches, varying in source, cationization method and degree of substitution were treated by a steam-jet cooking procedure, comparable to industrially employed starch cooking processes. The influence of the starch properties and cooking parameters on the adsorption behavior of the starches on cellulosic pulp was investigated. The adsorbed amount was affected by the cooking temperature and the type of starch. For some starch grades, a cooking temperature of 115 &deg, C can be employed to achieve sufficient starch retention on the pulp fibers. The energy consumption could further be reduced by cooking at higher starch concentrations without loss of adsorption efficiency.

A new method was developed to achieve highly selective monochlorination of α,ω-dihydridosiloxanes, ((H)Me2SiO-(SiMe2O)n-SiMe2(H), n = 0–2; (H)R2Si O-SiR2(H); R = Me, iPr, Ph; 3,5-dihydridooctamethyltetrasiloxane, Me3SiO-(Si(H)MeO)2 SiMe3) with trichloroisocyanuric acid (TCCA). The dependence of the selectivity of the monochlorination on the siloxane chain length is also discussed.

A novel synthetic pathway involving the desilylation of a tin trimethylsilyl species (Ph2Sn(SiMe3)2) towards nonprotected di(3-aminopropyl)tin dichloride ((H2N(CH2)3)2SnCl2) is described. Di(3-aminopropyl)tin dichloride is then converted to the respective dicarboxylates species (H2N(CH2)3)2Sn(OCOR)2 containing carboxylic acids of different lengths (R = –CH3, –(CH2)10CH3). Depending on the nature of R, discrete packing effects are observed in the solid state of di(3-aminopropyl)tin dicarboxylate derivatives. All the synthesized substances were characterized by 1H, 13C, and 119Sn nuclear magnetic resonance data and also single crystal X-ray analysis. These compounds are a promising class of substances for biological, pharmaceutical, and technical applications.

The rational control of the electronic and optical properties of small functionalized diamond-like molecules, the diamondoids, is the focus of this work. Specifically, we investigate the single- and double- functionalization of the lower diamondoids, adamantane, diamantane, and triamantane with −NH2 and −SH groups and extend the study to N-heterocyclic carbene (NHC) functionalization. On the basis of electronic structure calculations, we predict a significant change in the optical properties of these functionalized diamondoids. Our computations reveal that −NH2 functionalized diamondoids show UV photoluminescence similar to ideal diamondoids while −SH substituted diamondoids hinder the UV photoluminescence due to the labile nature of the S–H bond in the first excited state. This study also unveils that the UV photoluminescence nature of −NH2 diamondoids is quenched upon additional functionalization with the −SH group. The double-functionalized derivative can, thus, serve as a sensitive probe for biomolecu...

We present an ab initio parametrization scheme for explicitly dipole-polarizable force fields for the simulation of molecular liquids. The scheme allows for, in principle, arbitrarily coarse-grained representations. All parameters in the force field are derived from first-principles, based on simple physical arguments. Only one fit parameter enters the parametrization, a global scaling factor for the size of the particles, which is adjusted to reproduce the experimental mass density. As important examples and for the first time, polarizable coarse-grained force fields are derived for 1-alkyl-3-methylimidazolium cations with varying alkyl-chain lengths (alkyl = ethyl, butyl, hexyl) and hexafluorophosphate and tetrafluoroborate anions. Our findings are in good agreement with experimental results and results of further atomistic simulations. Hence, the force fields can be faithfully used where polarizability is expected to play a significant role, such as simulations of energy storage devices.

A series of novel and previously published tetraarylgermanes aryl4Ge (aryl = m-tolyl, 3,4-xylyl, 3,5-xylyl, 2-naphthyl) and triarylgermanium halides aryl3GeX (aryl = o-tolyl, 2,4-xylyl, 2,5-xylyl, 2,6-xylyl, 1-naphthyl, 2,4,6-mesityl, X = Cl, Br) were synthesized and characterized. All solids were investigated using single crystal X-ray diffractometry in order to elucidate the molecular structures. Effects of the substitution pattern of the aryl residue employed have been studied in terms of the impact on the product formation.

A series of bis(phenylacetylido)(porphyrinato) E(IV) (E=Si, Ge, Sn) derivatives were obtained by reacting lithium phenylacetylide with the corresponding bis(chlorido)(porphyrinato) E(IV) precursors. Crystal structure determinations demonstrated that thetrans-coordinated acetylide ligands deviate from their expected ideal geometry. Density functional theory calculations and comparison of the packing of the molecules among the homologous series of Si(IV), Ge(IV) and Sn(IV) revealed causes for the deviation from the simple valence shell electron pair repulsion model. Fluorescence and phosphorescence of these organometallic group 14 derivatives were studied and the results are compared to the literature-known properties of the related bis(chlorido)(porphyrinato) E(IV) compounds (E=Si, Ge, Sn). The first crystal structure of a porphyrinato Ge(IV) compound with σ-bonded acetylide ligands is reported.

The Soviet Union does not appear to be interested in long transoceanic voyages at the end of which an assault landing is made upon a distant shore. The mission for which the Soviets have constructed, and are continuing to construct, their amphibious force can be seen clearly both from what they are building and from what they have done with amphibious forces in the past. By 1939 the Soviet Navy was without amphibious forces of any type, though in July of that year a brigade of naval infantry was formed in the Baltic. In the current state of non-war, the Soviets often have found their amphibious ships to be useful. The places in and near Europe where the Soviets might find their amphibious forces useful in wartime are examined. One fact to keep in mind about amphibious operations is that a successful landing on a hostile coast is not the end of the seaborne part of the venture.