Azide monoliths as convenient flow reactors for efficient Curtius rearrangement reactions

The preparation and use of an azide-containing monolithic reactor is described for use in a flow chemistry device and in particular for conducting Curtius rearrangement reactions via acid chloride inputs.

Investigation of Petasis and Ugi reactions in series in an automated microreactor system

Petasis and Ugi reactions are used successively without intermediate purification, effectively accomplishing a six-component reaction. The examined reactions are transferred from traditional batch reactors to an automated continuous flow microreactor setup, where optimization and kinetic analyses are performed, proposed mechanisms evaluated, and rate-limiting steps determined.

The effect of alkyl substitution on the extraction properties of BTPhen ligands for the partitioning of trivalent minor actinides and lanthanides in spent nuclear fuels

Bis-triazinylphenanthroline ligands (BTPhens), which contain additional alkyl (n-butyl and sec-butyl) groups attached to the triazine rings, have been synthesized, and the effects of this alkyl substitution on their extraction properties with Ln(III) and An(III) cations in simulated nuclear waste solutions have been studied. The speciation of n-butyl-substituted ligand (C4- BTPhen) with some trivalent lanthanide nitrates was elucidated by 1 H-NMR spectroscopic titrations. These experiments have shown that the dominant species in solution were the 1:2 complexes [Ln(III)(BTPhen)2], even at higher Ln(III) concentrations, and the relative stability of 2:1 to 1:1 BTPhen-Ln(III) complexes varied with different lanthanides. As expected, sec-butylsubstituted ligand (sec-C4 BTPhen) showed higher solubility than C4-BTPhen in certain diluents. A greater separation factor (SFAm/Eu = ca. 210) was observed for sec-C4-BTPhen compared to C4-BTPhen (SFAm/Eu = ca. 125) in 1-octanol at 4 M HNO3 solutions. The greater separation factor may be due to the higher solubility of the 2:1 complex for sec-C4-BTPhen at the interface than the 1:1 complex of C4-BTPhen.

TESSA - Toolkit for experimentation with multimodal sensory substitution and augmentation

TESSA is a toolkit for experimenting with sensory augmentation. It includes hardware and software to facilitate rapid prototyping of interfaces that can enhance one sense using information gathered from another sense. The toolkit contains a range of sensors (e.g. ultrasonics, temperature sensors) and actuators (e.g. tactors or stereo sound), designed modularly so that inputs and outputs can be easily swapped in and out and customized using TESSA’s graphical user interface (GUI), with “real time” feedback. The system runs on a Raspberry Pi with a built-in touchscreen, providing a compact and portable form that is amenable for field trials. At CHI Interactivity, the audience will have the opportunity to experience sensory augmentation effects using this system, and design their own sensory augmentation interfaces.

The structural effect of Methyl substitution on the binding of Polypyridyl Ru-dppz Complexes to DNA

ABSTRACT: Polypyridyl ruthenium complexes have been intensively studied and possess photophysical properties which are both interesting and useful. They can act as probes for DNA, with a substantial enhancement in emission when bound, and can induce DNA damage upon photoirradiation and therefore, the synthesis and characterization of DNA binding of new complexes is an area of intense research activity. Whilst knowledge of how the binding of derivatives compares to the parent compound is highly desirable, this information can be difficult to obtain. Here we report the synthesis of three new methylated complexes, [Ru(TAP)2(dppz-10-Me).2Cl, [Ru(TAP)2(dppz-10,12-Me2)].2Cl and [Ru(TAP)2(dppz-11-Me)].2Cl, and examine the consequences for DNA binding through the use of atomic resolution X-ray crystallography. We find that the methyl groups are located in discrete positions with a complete directional preference. This may help to explain the quenching behavior which is found in solution for analogous [Ru(phen)2(dppz)]2+ derivatives.

Complementarity of neutron reflectometry and ellipsometry for the study of atmospheric reactions at the air–water interface

The combined application of neutron reflectometry (NR) and ellipsometry to determine the oxidation kinetics of organic monolayers at the air–water interface is described for the first time. This advance was possible thanks to a new miniaturised reaction chamber that is compatible with the two techniques and has controlled gas delivery. The rate coefficient for the oxidation of methyl oleate monolayers by gas-phase O3 determined using NR is (5.4 ± 0.6) × 10−10 cm2 per molecule per s, which is consistent with the value reported in the literature but is now better constrained. This highlights the potential for the investigation of faster atmospheric reactions in future studies. The rate coefficient determined using ellipsometry is (5.0 ± 0.9) × 10−10 cm2 per molecule per s, which indicates the potential of this more economical, laboratory-based technique to be employed in parallel with NR. In this case, temporal fluctuations in the optical signal are attributed to the mobility of islands of reaction products. We outline how such information may provide critical missing information in the identification of transient reaction products in a range of atmospheric surface reactions in the future.