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[en] Tilting of a deployed filter in the inferior vena cava (IVC) is a particular kind of periprocedural complication and this can reduce the filter's clot-trapping ability and increase the occlusion of the IVC at a later period. The authors report here on a case of spontaneous tilting of an inferior vena caval filter that was associated with thrombosis in the IVC within 2 weeks of the initially successful placement of the filter without tilting
[en] Highlights: • Successfully intercalation of dual-surfactants into montmorillonite. • Preparation of phosphonium-ammonium-modified montmorillonites. • Hybrid-organic-montmorillonite (HOMt) with intermediate properties. • Statistical approach to optimize the hybrid montmorillonite properties.
[en] Various equilibrium and nonequilibrium aspects of staging and stage transformations in graphite intercalation compounds are investigated. A simple thermodynamic model of intercalated graphite that allows for variation of in-plane intercalant density and takes explicit account of volume variation is presented. Assuming random occupation of intercalant atoms, pressure-temperature-concentration phase diagrams are calculated. The model is capable of explaining pressure-induced staging transformation, the appearance of fractional stage at high pressure, and other experimentally observed effects in alkali metal-graphite compounds. In order to address the mechanism of stage transformations a set of diffusion equations based on time-dependent Landau-Ginzburg theory is derived. As illustrations of the formalism, stage decomposition in a quenched sample and the intercalation of a dilute sample are studied. Staggered domains of intermediate stages are shown to arise naturally as a consequence of the interactions and the kinetic constraints. Further, it is shown that intercalation proceeds through the formation and migration of islands of intermediate stages. All the results are in qualitative agreement with experiments
[en] Highlights: • Seven Sleeping Beauties were identified in Paul Hagenmuller's work. • Sleeping Beauties are papers with delayed recognition in terms of citations. • The Sleeping Beauties relate to work on silicon clathrate, sodium cobaltate, and sodium-ion battery research. • The occurrence of Sleeping Beauties challenges the use of short-term citation-based metrics for the evaluation of scientific impact. - Abstract: Paul Hagenmuller (1921−2017) is an important figure of French solid-state chemistry, who enjoyed scientific and institutional recognition. He published 796 papers and has been cited more than 16,000 times. This paper explores Hagenmuller's work using scientometric analysis to reveal the impact of his work, his main research topics and his collaborations. Although Hagenmuller was a recognized scientist, a subset of his work, now highly cited, attracted little attention at the time of publication. To understand this phenomenon, we detect and study papers with delayed recognition, also called 'Sleeping Beauties' (SBs). In scientometrics, SBs are publications that go unnoticed, or 'sleep' for a long time before suddenly attracting a lot of attention in terms of citations. We identify 7 SBs published between 1965 and 1985, and awakened between 1993 and 2010. The first SB reports the discovery of the clathrate structure of silicon. The second reports the isolation of four new phases with the formula NaxCoO2 (x < =1). The five other SBs investigate the electrochemical intercalation and deintercalation of sodium, and the structure and properties of layered oxides. Through interviews with his coworkers, we attempt to identify the reasons for the delayed recognition and the context of the renewed interest in those papers.
[en] The supramolecule, p-t-Butyl calix(8)arene, forms inclusion complex with the antiseizure drug molecule, ethosuximide. This feature is explained on the basis of optical absorption spectroscopy. Here p-t-Butyl calix(8)arene is the host molecule and ethosuximide is the guest molecule. The stoichiometry of the host–guest complex and the binding constant has been determined using Benesi–Hildebrand plot. Based on the result obtained the structure of the inclusion complex has been proposed. -- Highlights: ► Third generation supramolecule, t-butyl calix (8) arene, is used as a host molecule. ► Anti seizure drug molecule is used as a guest molecule. ► Inclusion complex is formed between the host and guest molecule
[en] Methane is an active Greenhouse effect gas whose concentration will likely increase in the future. The possible destabilisation of CH4 clathrates (hydrates) due to anthropogenic climate warming, and the resulting outgasing of methane, could lead to a major increase of the global Greenhouse effect, with dramatic consequences for Humanity. For these reasons, the study of possible countermeasures should be actively considered. Here, we suggest taking advantage of the thermodynamic instability of CH4 in air, and search for ways to oxidize it
[en] The inclusion behavior of isoniazid with β-cyclodextrin (β--CD) in the liquid and solid state were investigated. The absorption spectral of UV-Vis was used to determine the inclusion behavior in the liquid state. Fourier Transform Infrared (FTIR) spectrometer, Thermogravimetric Analysis (TGA), and Nuclear Magnetic Resonance (NMR) were used to investigate the inclusion behavior in the solid state. The kneading between isoniazid and β--CD was performed to produce the inclusion complex. The formation constant (K) of the inclusion complex (β--CD/isoniazid) was calculated using Benesi-Hildebrand. The results of 1H NMR and NOESY indicated that β--CD formed hydrophobic interaction with isoniazid. The values of formation constant for the complex of β--CD/isoniazid at pH 4 and 9 were 17.15 and 9.86, respectively. Meanwhile, the value of formation constant for the complex at the natural condition was 25000. The stoichiometry ratio obtained for the complex of β--CD/isoniazid in acidic and basic conditions are 1:1. Meanwhile, 1:2 ratio of β--CD and isoniazid was found at natural condition. (author)