A Double-Site Chemodosimeter for Selective Fluorescence Detection of a Nerve Agent Mimic

A novel two-site chemodosimeter (SWJT-4) based on fluorescein skeleton to detect diethyl chlorophosphate (DCP) was designed and synthesized. It is a turn-on fluorescent probe for DCP with good selectivity and obvious color change in aqueous solution. Interestingly, the two oxime groups of SWJT-4 as dual response sites initiated different reactions with DCP to form a cyano group and an isoxazole ring, respectively. The corresponding mechanism was confirmed by 1H NMR, MS and DFT calculation. Moreover, SWJT-4 could be used as a fluorescent test paper to detect DCP vapor.

Design of Frustrated Lewis Pair in Defective TiO2 for Photocatalytic Non-Oxidative Methane Coupling

The efficient C-H polarization is the prerequisite for the low-temperature photocatalytic CH4 conversion, which however is restricted by the poor stretching ability of short-distanced lattice atoms. Herein, frustrated Lewis pair (FLP) composed of doped ion in TiO2 as Lewis acid (LA) and neighboring Ti-OH as Lewis base (LB) with a long distance (0.31-0.37 nm) were designed through DFT calculation and fabricated by hydrogenation treatment of metal-doped TiO2-SiO2 with macroporous-mesoporous structure. Benefitting from the long LA-LB distance and matched acid-base intensity, hydrogenated Ga-doped composite achieves superior C-H stretching with a high CH4 conversion rate (139 µmol g−1 h−1) to ethane. The photo-irradiation causes the electron excitation from Ga to Ti-OH according to the time-dependent DFT calculation and in situ EPR analysis, which promotes the formation and coupling of ·CH3. This work provides a key underpinning for regulating the characteristics of FLP for C-H activation and C-C coupling via light irradiation.

Effect of Solute Ta on Grain Refinement of Al-7Si-0.3Mg Based Alloys

Different Ta concentrations together with stochiometric grain refiner (Al-2.2Ti-1B) in Al-Si-Mg based alloys were investigated with the aim to elucidate grain refinement mechanisms. Post-solidification microstructure was characterised using optical microscopy and scanning electron microscopy (SEM), with a special focus on the Ta-rich layer (more likely to be Al3Ta) on the basal planes (0001) of TiB2. A significant grain refinement was observed by using the solute Ta together with stochiometric grain refiner (Al-2.2Ti-1B). In order to further elucidate the formation of Ta-rich layer on the basal planes (0001) of TiB2, the Density Functional Theory (DFT) calculation were also performed to determine the interface energies of different interfaces and sandwich configurations, including Al (111), Al3Ti (112) and Al3Ta (112) at the interface of TiB2 basal plane (0001). It was found that the interface energy for Ti-terminated TiB2 at the interface throughout all configurations involved in this paper is lower than that for B-terminated TiB2, indicating that Ti-terminated TiB2 is more favourable. It was also found that the Al3Ta configuration yields the same interface energies as the Al3Ti configuration. Furthermore, the interface energy of the sandwich configuration also shows nearly identical values along the TiB2 // Al3Ti and TiB2 // Al3Ta interface energy, strongly indicating that the solute Ti can be fully replaced by the solute Ta.

Encapsulation of anticancer drug Ibrance into the CNT(8,8-7) nanotube: A study based on DFT method

In this research, a DFT calculation was performed for study to investigate the encapsulation of the anticancer drug Ibrance into CNT(8,8-7) by using M062X/6-311G * level of theory in the solvent water. TD-DFT method was used to compute the electronic spectra of the Ibrance drug, CNT(8,8-7) and complex CNT(8,8-7)/Ibrance in aqueous medium for the study of non-bonded interaction effect. The non-bonded interaction effects of Ibrance drug with CNT(8,8-7) on the electronic properties and natural charges have been also studied. The results display the change in title parameters after process adsorption. According to NBO results, the molecule Ibrance and CNT(8,8-7) play as both electron donor and acceptor at the complex CNT(8,8-7)/Ibrance. Charge transfer, on the other hand, occurs between the bonding, antibonding, or nonbonding orbitals of Ibrance drug and CNT (8,8-7). According to QTAIM analysis and the LOL and ELF values, all intermolecular bonds in the complex are non-covalent in nature. As a result, CNT(8,8-7) can be thought of as a drug delivery system for transporting Ibrance as an anticancer drug within biological systems.