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The elaboration of performant, selective and re-usable catalyst systems is still an area of intense research activity. Porous silica based materials inspired from Ionic Liquids have high potential in catalysis and recently initiated further developments in the area of silica supported catalytic phases. Here, we will illustrate various strategies for the elaboration of ionosilica derived heterogeneous catalysts. Three approaches for obtaining ionosilica derived heterogeneous catalysts will be described. We will show that catalytic ionosilicas can be obtained via anion exchange. These materials can further be used to access ionosilica supported metal nanoparticles. Finally, metal free ionosilicas are interesting heterogeneous organocatalysts. In summary, ionosilicas appear as highly versatile phases for the preparation of various types of heterogeneous catalysts that open interesting perspectives both in transition metal catalysis and organocatalysis.

PURPOSE:This study compared the efficacy and safety of suberoylanilide hydroxamic acid (SAHA) and mitomycin C (MMC) up to 4 months in the prevention of corneal haze induced by photorefractive keratectomy (PRK) in rabbits in vivo.METHODS:Corneal haze in rabbits was produced with −9.00 diopter PRK. A single application of SAHA (25 Corneal haze in rabbits was produced with −9.00 diopter PRK. A single application of SAHA (25 μM) or MMC (0.02%) was applied topically immediately after PRK. Effects of the two drugs were analyzed by slit-lamp microscope, specular microscope, TUNEL assay, and immunofluorescence.RESULTS:Single topical adjunct use of SAHA (25 Single topical adjunct use of SAHA (25 μM) or MMC (0.02%) after PRK attenuated more than 95% corneal haze and myofibroblast formation (P< .001). SAHA did not reduce keratocyte density, cause keratocyte apoptosis, or increase immune cell infiltration compared to MMC (P< .01 or .001). Furthermore, SAHA dosing did not compromise corneal endothelial phenotype, density, or function in rabbit eyes, whereas MMC application did (P< .01 or .001).CONCLUSIONS:SAHA and MMC significantly decreased corneal haze after PRK in rabbits in vivo. SAHA exhibited significantly reduced short- and long-term damage to the corneal endothelium compared to MMC in rabbits. SAHA is an effective and potentially safer alternative to MMC for the prevention of corneal haze after PRK. Clinical trials are warranted.[[J Refract Surg.2017;33(12):834–839.]

Periodic mesoporous ionosilica nanoparticles with ammonium walls were synthesized exclusively from a trisilylated ammonium precursor. The nanoparticles display a uniform particle size, together with a high specific surface area and an ordered hexagonal pore architecture. Completely biocompatible in vitro and in vivo, the nanoparticles are efficiently endocytosed by RAW 264.7 macrophages and used as carrier vehicles for anionic drugs. Diclofenac-loaded ionosilica nanoparticles are very efficient in inhibiting lipopolysaccharides-induced inflammation.

Ionosilica are mesoporous silica-based hybrid materials containing covalently bound ionic groups. The mixed ionic mineral nature confers particular properties to these materials. Here, we focus on the tailoring of the interfacial properties of ionosilicas. Three materials were synthesized from three different oligosilylated ammonium precursors. Furthermore, anion exchange allowed replacing the halide in the parent ionosilicas by more hydrophobic anions, e.g., thiocyanate (SCN–) and bis(trifluoromethane)sulfonimide (NTf2–). Both the constitution of the ammonium substructure of the precursor and the nature of the counteranion allow controlling the interfacial properties in terms of hydrophilicity and affinity toward different types of solvents. Although all studied ionosilica are highly hydrophilic mesoporous materials, significant differences and clear trends could be observed. As shown via competitive 1-butanol adsorption measurements in the liquid phase and solvent vapor adsorption from the gas phase, the interfacial properties of ionosilicas can be fine-tuned either by the use of more hydrophobic ammonium precursors or the incorporation of hydrophobic anions. We therefore show that ionosilicas combine high porosity, regular architecture on the mesoscopic level with an unmatched chemical versatility, induced by the high variability and the high number of homogeneously distributed ionic species. Ionosilicas appear as highly adaptable materials and can be considered as “designer materials”, which are interesting for applications in catalysis, sorption, and separation.

The martensitic face-centered cubic (fcc) to hexagonal close-packed (hep) transformation was studied in cobalt thin films on silicon substrates in order to understand effects of film constraints, texture and stress state. The martensitic transformation was observed in situwith the substrate curvature method. The transformation manifests itself as a stress drop revealing a positive work. However, with increasing tensile stress, the start of the martensite transformation is shifted to lower temperature. Thus, stress obstructs the transformation in spite of the positive sign of the transformation work. A dislocation-based model for the martensite nucleation is presented and applied to Co thin films. A distinction is made between a microscopic shape changeand a macroscopic shapechange. The model predicts the stress-induced delayed nucleation due to the microscopic shape change. The positive work results from the macroscopic shape change. Within experimental error, model and experiments agree well.

This work describes the synthesis of novel functional silica materials with difunctional thiol–amide substructures and featuring regular architectures on a mesoscopic level. The functional materials were synthesised by both one‐pot co‐condensation and post‐grafting approaches. The thiol groups confined in the matrix were found to be efficient for palladium entrapment, leading to highly active and reusable heterogeneous catalysts for Sonogashira and Suzuki–Miyaura cross‐coupling reactions. This work evidences the crucial role of both the thiol precursor and the condensation degree of the silica scaffold in view of the design of stable and reusable tailor‐made mesoporous catalytic silica materials.

Trialkoxysilylated camphorsulfonamides have been used for the synthesis of functional organosilicas in a template‐directed hydrolysis‐polycondensation with tetraethylorthosilicate (TEOS). The sol–gel transformation leading to the formation of highly ordered materials indicates that trialkoxysilylated camphorsulfonamides allow the synthesis of functional organosilicas with high structural regularity. This behaviour arises from the affinity of the chiral precursors towards the lyotropic phase of the ionic surfactants in the aqueous hydrolysis‐polycondensation mixture. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

The replacement of toxic CrVIfor O2and of chlorinated solvents for supercritical carbon dioxide (or ionic liquids) in the oxidation of alcohols remains hindered by the low selectivity and activity of the current heterogeneous catalysts. Using an integrated approach that combines sol–gel entrapped perruthenate as aerobic catalyst, an encapsulated ionic liquid as solubility promoter, and scCO2as the reaction solvent, we have developed a system capable of rapidly converting different alcohols into carbonyl compounds with complete selectivity, including substrates which are otherwise difficult to oxidise. The methodology is generally applicable and may easily be extended to other waste‐free, catalytic syntheses of fine chemicals.

The synthesis of two task‐specific ionic liquids (TSILs) bearing 2‐hydroxybenzylamine entities is described. These compounds are based on an imidazolium substructure onto which one hydrobenzylamine‐complexing moiety is grafted. We have demonstrated that, whether pure or diluted, TSIL is able to extract americium ions. Furthermore, recovery of americium from the IL phase into a receiving phase can be achieved under acidic conditions. A possible mechanism for the metal‐ion partitioning is presented, in which the extraction system is driven by an ion‐exchange mechanism.

For the first time, the study of a three‐step extraction system of water/ionic liquid/supercritical CO2has been performed. Extraction of trivalent lanthanum and europium from an aqueous nitric acid solution to a supercritical CO2phase via an imidazolium‐based ionic liquid phase is demonstrated, and extraction efficiencies higher than 87 % were achieved. The quantitative extraction is obtained by using different fluorinated β‐diketones with and without the addition of tri(n‐butyl)phosphate. The complexation phenomenon occurring in the room‐temperature ionic‐liquid (RTIL) phase was evidenced by using luminescence spectroscopy.

The spectroscopic characteristics (excitation, emission and lifetime) of Eu^III dissolved in 1-methyl-3-butylimidazolium bis(trifluoromethanesulfon)imide (BumimTf2N) are reported. In a first series of experiments, the effect of the presence of water in BumimTf2N was examined. It appears that non-degassed solutions are most probably inhomogeneous, displaying large water clusters leading to an intense diffusion of the red light of an He:Ne laser. In these samples, the Eu emission spectrum is close to that observed in slightly acidic aqueous solutions. In contrast, when the samples were degassed the solution appeared homogeneous and water can be considered as a competitive ligand for the first coordination sphere of Eu. In a subsequent series of experiments, tetrabutylammonium chloride (TBACl) was added to the solution and the resultant species investigated. The ensuing enhancement in the metal-centered luminescence has been interpreted in terms of changes in the inner coordination sphere of the Eu^III ion and possible structures are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

The radical crosslinking polymerization of styrene with (R)-divinyl-BINOL derivatives results in the formation of reticulated polystyrene networks containing protected (R)-BINOL entities at each junction of the polystyrene chains. The generation of polystyrene-immobilized free (R)-BINOL was performed by cleaving the protecting ether groups under acidic conditions. The resulting materials containing optically active BINOL units were tested as chiral ligands in the enantioselective addition of diethylzinc to benzaldehyde. The catalytic properties of the polymer gels were shown to be highly dependent on the degree of reticulation: in the best cases, the resins incorporating (R)-BINOL units showed activities and selectivities similar to those of molecular (R)-BINOL. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

By identifying the sequence of retro- and lentiviral integration sites in peripheral blood leukocytes, the clonal composition and fate of genetically modified hematopoietic progenitor and stem cells could be mapped in vitro and in vivo. Previously available methods have been limited to the analysis of mono- or oligoclonal integration sites present in high copy numbers. Here, we perform characterization of multiple rare retroviral and lentiviral integration sites in highly complex DNA samples. The reliability of this method results from nontarget DNA removal via magnetic extension primer tag selection (EPTS) preceding solid-phase ligation-mediated PCR. EPTS/LM-PCR allowed the simultaneous direct genomic sequencing of multiple proviral LTR-flanking sequences of retro- and lentiviral vectors even if only 1 per 100 to 1000 cells contained the provirus. A primer walking "around" the integration locus demonstrated the adaptability of EPTS/LM-PCR to study unknown flanking DNA regions unrelated to proviruses. The technique is fast, inexpensive, and sensitive in minimal samples. It enables studies of retro- and lentiviral integration, viral vector tracking in gene therapy, insertional mutagenesis, transgene integration, and direct genomic sequencing that until now have been difficult or impossible to perform.

Polysilsesquioxane hybrid materials containing chiral binaphthyl moieties are readily available by coupling (R)- or (S)-2,2′-dihydroxy-1,1′-binaphthyl (BINOL) with 3-(triethoxysilyl)propyl isocyanate and subsequent hydrolysis polycondensation of the resulting bis-trialkoxysilylated carbamate precursor. Rhodium species were embedded in the chiral hybrid matrix. The catalytic properties of the solids were evaluated in hydride-transfer reduction to prochiral ketones.When the catalytic species were embedded in an entirely chiral network, enantiomeric excesses up to 45% were observed.

The synthesis of 4-vinylstilbenes was accomplished by the Heck and Wittig reactions. Bromination of polystyrene was achieved by an iron-catalyzed electrophilic substitution reaction. Polymer-analogous coupling reactions of styrenes with respect to stilbenes with poly(bromostyrene)s was accomplished by Heck- reactions under optimized reaction conditions and is reported with respect to the molecular weight of the poly(bromostyrene)s. Thermal and optical properties are discussed with respect to light-emitting diode applications. © 1997 John Wiley & Sons, Ltd.

A comparison betweeen the electropherograms of the spelt and wheat cultivars showed specific differences in the gliadin band patterns which provided the possibility of a clear classification into spelt or wheat. A special nomenclature was developed to be able to improve the presentation of the gliadin band pattern of spelt, which is different from that of wheat. This nomenclature, however, has not yet been applied to other cereals. The gliadin band patterns were presented in a schematic form. As a parameter for comparison, idealized band patterns of both wheat and spelt were developed by comparing the proportions of the bands of all available types. When comparing the gliadin band patterns of the spelt cross-breeds with their corresponding parental generations, it was noted that the same parental bands were not always transmitted and that the cross-breeds showed differences in the intensity, mobility, occurrence, and the splitting of single bands. In general it can be said that the band pattern of the daughter generation — even in the examined F5and F6generations — is more similar to the band pattern of the mother than to that of the father, which proves a maternal effect.

Giemsa's solution and the fluorescent agents Hoechst 33258, DAPI and quinacrine were applied to chromosomes of rye in order to obtain reliable banding techniques. Methodical improvements led to distinct Giemsa C-banding patterns revealing a high number of interstitial bands which allow the discrimination even between closely related rye forms. Hoechst 33258 performed a clear fluorescent banding pattern in rye chromosomes while DAPI showed a similar but less bright fluorescence. Quinacrine proved to be an inadequate tool for rye cytogenetics, although in interphase nuclei regions of brighter fluorescence appeared. Comparing Giemsa C- and Hoechst 33258 banding, the latter could serve for a rapid identification of rye chromosomes, however, Giemsa C-banding is the method at choice for detailed analysis.Heredity (1988) 61, 459–467; doi:10.1038/hdy.1988.139

Fixed pollen tubes of Tradescantia paludosawere cytologically investigated to analyse the immigration of generative and vegetative nuclei into the pollen tube and the mode of their migration within the pollen tube in order to test the correlation between the position of the nuclei in the pollen tube and the length of it.

7 Jahre sind seit der kurzen Steinkohlentagung der Gesellschaft in Essen und erst 3 Jahre seit dem letzten Heerlener Kongreß vergangen. Anders als der Heerlener Kongreß mit seiner überregionalen Aufgabe und seinem Charakter einer Tagung, auf welcher gewisse Absprachen in allgemein verbindlicher Form getroffen werden, hatte sich diese Frühjahrstagung auf das westdeutsche Steinkohlengebirge beschränkt. Dessen Erforschung war in den letzten Jahren so belebt worden, daß eine Aussprache lohnend erschien, die dann auch ausländische Geologen angezogen hat. Ein nicht unbedeutender Zweck einer Tagung ist indessen in der Fortwirkung des Gebotenen zu sehen. Um diese zu begünstigen, soll eine Rückschau auf den erzielten Stand der Forschung und ihre Lücken sowie ein Ausblick auf die künftigen Schwerpunkte versucht werden. Oberste-Brink formulierte die Fragen des Bergbaus an die westdeutsche Steinkohlengeologie und umriß damit den Sinn der Frühjahrstagung für die praktische Bedeutung der mitgeteilten Untersuchungen. Wie ein roter Faden zog sich die angewandte Seite der Forschungsergebnisse durch alle Vorträge und Veröffentlichungen. So ist das wissenschaftliche und praktische Fazit der neuen Erkenntnisse über die Paläogeographie der subvariscischen Vortiefe gleich wichtig. Die Fortsetzung der kaledonischen Faltenzüge des Brabanter Massivs unter dem Ruhrkarbon, die genauere Abzeichnung der Ränder der Vortiefe, das vorlandwärtige Vorrücken der flözführenden Fazies und die aus dem Übergreifen roter Schichten des Westfal D über Westfal B bei Winterswijk hervorgehende Fortdauer von Bewegungen in der Westfalzeit, das alles kann man als gesicherte neue Erkenntnis übernehmen (R. Teichmüller). Die Paläogeographie des Oberkarbons konnte weiter aufgehellt werden durch neue Tiefbohrungen im Raume zwischen Ruhr und Nordsee sowie durch fortgesetzte Studien von Kohlen- und anderen Geröllen. Es sei nur auf die überraschend große Mächtigkeit des Namur C und dessen ausgedehnte Rotfärbung in der Bohrung Bielefeld (Fabian) hingewiesen. Die Vermutung, daß der Südrand des Karbontroges nicht sehr weit entfernt war, erhält durch die Devon-Kalkgerölle im Finefrau-Konglomerat von Duisburg eine weitere Stütze (Schaub).

Copperii can be extracted in supercritical CO2from a room temperature ionic liquid using CO2-philic fluorinated β-diketonate ligands; thanks to the 1-butyl-3-methylimidazolium bistrifluoromethylsulfonylimide BMIMTf2N ionic liquid properties, there is no need to add modifiers to the neat supercritical CO2to reach high extraction efficiencies.

Ordered mesoporous silicas with hexagonal or lamellar architectures incorporating covalently bound ionic species were synthesized viaa template directed hydrolysis–polycondensation of tetraethoxysilane (TEOS) with triethoxysilylated imidazole [(EtO)3Si(CH2)3–Im] or alkylimidazolium halides [(EtO)3Si(CH2)3–Im+–R Hal−].

Mesoporous thin films functionalized with silylated β-diketone compounds with symmetry mesostructure dependent on the probe quantity were used as fast uranyl species sensors with high selectivity and sensitivity.