Search results for "Salt"

1972

The metathesis reaction of cyclooctene was investigated with respect to the solvent, the catalyst, and the ratio of its components. A necessary condition for an active metathesis catalyst appears to be the presence of two transition metal-carbon bonds in a complex of the transition metal compound with an aluminum halide. A structure for the active complex is proposed. Die Metathese-Reaktion von Cycloocten wurde unter dem Einflus verschiedener Losungsmittel, verschiedener Katalysatorsysteme und Verhaltnisse der Katalysatorkomponenten untersucht. Die Ergebnisse lassen darauf schliesen, das die aktiven Katalysatoren Komplexe besonderer Ubergangsmetallverbindungen mit Aluminiumhalogeniden darst…

CCDC 955127: Experimental Crystal Structure Determination

2013

Related Article: Eugenio Coronado, Simona Curreli, Carlos Giménez-Saiz, Carlos J. Gómez-García, Antonio Alberola and Enric Canadell|2009|Inorg.Chem.|48|11314|doi:10.1021/ic9018103

CCDC 955126: Experimental Crystal Structure Determination

2013

Related Article: Eugenio Coronado, Simona Curreli, Carlos Giménez-Saiz, Carlos J. Gómez-García, Antonio Alberola and Enric Canadell|2009|Inorg.Chem.|48|11314|doi:10.1021/ic9018103

Synthesis, Characterization, and Saccharide Binding Studies of Bile Acid − Porphyrin Conjugates

2007

Synthesis and characterization of bile acid-porphyrin conjugates (BAPs) are reported. Binding of saccharides with BAPs in aqueous methanol was studied by monitoring changes in the visible absorption spectral of the porphyrin-moieties. Although these studies clearly showed absorbance changes, suggesting quite high if non-selective binding, the mass spectral studies do not unambiguously support these results.

Surfactant self-assembly in the gas phase: Bis(2-ethylhexyl)sulfosuccinate- alkaline metal ion aggregates

2008

Molecular dynamics (MD) simulations were conducted for systems in vacuo consisting of n AOT anions (bis(2-ethylhexyl)sulfosuccinate ions) and n 1 or n Na+ ions up to n = 20. For n = 15, positively charged systems with Li+, K+, and Cs+ cations were also considered. All systems were observed to form reverse micelle-like aggregates whose centre is occupied by cations and polar heads in a very compact solid-like way, while globally the aggregate has the form of an elongated and rather flat ellipsoid. Various types of statistical analyses were carried out on the systems to enlighten structural and dynamical properties including gyration radius, atomic pair correlation functions, atomic B-factor …

In vitro anti-biofilm activity of Boswellia spp. oleogum resin essential oils

2009

Aims:  To evaluate the anti-biofilm activity of the commercially available essential oils from two Boswellia species. Methods and Results:  The susceptibility of staphylococcal and Candida albicans biofilms was determined by methyltiazotetrazolium (MTT) staining. At concentrations ranging from 217·3 μg ml−1 (25% v/v) to 6·8 μg ml−1 (0·75% v/v), the essential oil of Boswellia papyrifera showed considerable activity against both Staphylococcus epidermidis DSM 3269 and Staphylococcus aureus ATCC 29213 biofilms. The anti-microbial efficacy of this oil against S. epidermidis RP62A biofilms was also tested using live/dead staining in combination with fluorescence microscopy, and we observed that …

Structural and dynamical characterization of melt PEO–salt mixtures

2002

Abstract Salt doped poly ethylene oxide (PEO) mixtures were investigated by means of both small angle neutron scattering and QENS techniques aiming to characterize morphological and dynamical features in the melt state. These experimental evidences provide support to the proposed heterogeneous scenario for polymer electrolytes. In particular, the existence of PEO–cation complexes is proposed to play a major role in intramolecular cooperation and intermolecular transient crosslinks, which affects the mixture properties.

Morphology of solid polymer electrolytes: a TR WAXS investigation

2002

A wide angle X-ray scattering investigation of (polyethylene oxide)n–sodium thiocyanate [(PEO)nNaSCN] mixtures is reported. Temperature dependence analysis for different mixtures is shown, in order to rationalize the multi-phase behaviour. Depending on the amount of salt added and upon the temperature considered three different phases have been found to simultaneously coexist: crystalline PEO, amorphous PEO, and crystalline complex.

The effects of structural changes on the anti-microbial and anti-proliferative activities of diimidazolium salts

2017

An array of diimidazolium salts has been synthesized and used to investigate their anti-microbial and anti-proliferative activities. In particular, salts based on the 3,30-di-n-alkyl-1,10-(1,n-phenylenedimethylene)- diimidazolium cation and differing in the alkyl chain length on the imidazolium ion, the isomeric substitution on the aromatic spacer and in the anion nature were used. The anti-proliferative activity was evaluated against cervical (HeLa), colon adenocarcinoma (HT-29) and breast (SKBR3) cancer cell lines. In the latter case, also a morphological assessment after treatment with salts was performed. All salts were tested for their hemolytic activity against human erythrocytes. On …

Topologically Novel Multiple Rotaxanes and Catenanes Based on Tetraurea Calix[4]arenes

2006

Calix[4]arenes bearing at their wide rim four urea residues easily form hydrogen bonded dimeric capsules. This has been used to preorganise alkenyl functions attached to these urea groups for their controlled connection via metathesis reaction. Multimacrocyclic tetraurea derivatives are thus obtained in excellent yields via heterodimers which are formed exclusively with tetratosylurea derivatives. Heterodimerisation of such bis- and tetraloop tetraureas leads analogously to multicatenanes, or to rotaxanes by stoppering. Huge macrocycles are detached from tetraloop derivatives by cleavage of the urea function.