The solubility of lithium salts in dimethyl carbonate ͑DMC͒ found in solid electrolyte interface ͑SEI͒ films was determined. The salt-DMC solutions evaporated, and the salts were transferred into water for ion conductivity measurements. The salts examined included lithium carbonate ͑Li 2 CO 3 ͒, lithium oxalate ͓͑LiCO 2 ͒ 2 ͔, lithium fluoride ͑LiF͒, lithium hydroxide ͑LiOH͒, lithium methyl carbonate ͑LiOCO 2 CH 3 ͒, and lithium ethyl carbonate ͑LiOCO 2 C 2 H 5 ͒. The salt molarity in DMC ranged from 9.6 ϫ 10 −4 mol L −1 ͑LiOCO 2 CH 3 ͒ to 9 ϫ 10 −5 mol L −1 ͑Li 2 CO 3 ͒ in the order of LiOCO 2 CH 3 Ͼ LiOCO 2 C 2 H 5 Ͼ LiOH Ͼ LiF Ͼ ͑LiCO 2 ͒ 2 Ͼ Li 2 CO 3. X-ray photoelectron spectroscopy measurements on SEI films on the surface of the negative electrode taken from a commercial battery after soaking in DMC for 1 h suggested that the films can dissolve. Separately, the heat of dissolution of the salts was calculated from computer simulations for the same salts, including lithium oxide ͑Li 2 O͒, lithium methoxide ͑LiOCH 3 ͒, and dilithium ethylene glycol dicarbonate ͓͑CH 2 OCO 2 Li͒ 2 :LiEDC͔ in both DMC and ethylene carbonate ͑EC͒. The results from the computer simulations suggested that the order in which the salt was likely to dissolve in both DMC and EC was LiEDC Ͼ LiOCO 2 CH 3 Ͼ LiOH Ͼ LiOCO 2 C 2 H 5 Ͼ LiOCH 3 Ͼ LiF Ͼ ͑LiCO 2 ͒ 2 Ͼ Li 2 CO 3 Ͼ Li 2 O. This order agreed with the experiment in DMC within the experimental error. Both experiment and computer simulations showed that the organic salts are more likely to dissolve in DMC than the inorganic salts. The calculations also predicted that the salts dissolve more likely in EC than in DMC in general. Moreover, the results from the study were used to discuss the capacity fading mechanism during the storage of lithium-ion batteries.

Sensing from the ultraviolet to the infrared is important for a number of scientific and industrial applications. Poly(4-vinyl pyridine) swollen in liquid pyridine functions as a photoconductive gel sensitive to irradiation in the ultraviolet. By blending poly(4-vinyl pyridine) with poly(4-vinyl pyridineco-butyl methacrylate), we have now succeeded in expanding the range of wavelength sensitivity of the gel to cover the whole visible spectrum. Furthermore, addition of a small amount of 4-hydroxypyridine to the polymer blend results in unusually high thermal sensitivity (TCR = (0.1−0.16)/1 °C). Spectroscopic measurements show that the combined processes of proton transfer and electron transfer, occurring in a DC electric field, contribute to the gel properties. The optimized system has potential application as a simple and inexpensive active layer in organic photovoltaic cells as well as a thermal sensor.

The interactions of the polymer poly(4-vinyl pyridine) moieties with free pyridine molecules in concentrated solution develop protonated and hydrogen-bonded species on the polymer backbone and turn the viscous solution to gel. Direct irradiation at proton transfer centre on the protonated polymer moiety promotes an amorphous-to-crystalline transition. The polymer crystals exhibit completely different optical properties when compared to the amorphous material. The proposed mechanism of the photoinduced crystallisation is the following: direct excitation to the proton transfer centre generates in abundance protonated polymer moieties, which have rigid quinone structure. Rigid quinone conformations stimulate the crystallisation of the polymer chains; in their turn, increasing polymer ordering stabilises the photoinduced protonated species. Photoinduced phase transition is reversible, meaning, that crystalline phase is metastable. To clarify the mechanism of the phase transition, in the present issue, using molecular modelling, we investigate the conformational behaviour of the polymer species depending on the state of protonation, interaction with adjacent solvent molecules and polymer side-chain units. The Density Functional Theory (DFT) calculations show the protonated pyridine moiety as a quinone structure that is clearly stable, thus emphasising the ability of such structure to play a key role as a 'working' species.

Synthetic biology is a nascent field that emerged in earnest only around the turn of the millennium. It aims to engineer new biological systems and impart new biological functionality, often through genetic modifications. The design and construction of new biological systems is a complex, multistep process, requiring multidisciplinary collaborative efforts from "fusion" scientists who have formal training in computer science or engineering, as well as hands-on biological expertise. The public has high expectations for synthetic biology and eagerly anticipates the development of solutions to the major challenges facing humanity. This article discusses laboratory practices and the conduct of research in synthetic biology. It argues that the fusion science approach, which integrates biology with computer science and engineering best practices, including standardization, process optimization, computer-aided design and laboratory automation, miniaturization, and systematic management, will increase the predictability and reproducibility of experiments and lead to breakthroughs in the construction of new biological systems. The article also discusses several successful fusion projects, including the development of software tools for DNA construction design automation, recursive DNA construction, and the development of integrated microfluidics systems.

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