1. Photoresponsive properties at (0 0 1), (1 1 1) and (1 1 0) LaAlO3/SrTiO3 interfaces
Hong Yan, Zhaoting Zhang, Ming Li, Shuanhu Wang, Lixia Ren, Kexin Jin J Phys Condens Matter. 2020 Mar 27;32(13):135002.doi: 10.1088/1361-648X/ab5ebf.
We report the photoresponsive characteristics of (0 0 1), (1 1 0), and (1 1 1) LaAlO3/SrTiO3 heterointerfaces deposited at different oxygen pressures using a 360 nm light. The results show that LaAlO3/SrTiO3 interfaces with less oxygen vacancies exhibit a larger resistance change when illuminated by light and a slower recovery process when light is off. In addition, the (1 1 0) LaAlO3/SrTiO3 heterointerfaces present the smallest photoinduced change and residual photoinduced change in the resistance, which are related to the negligible polarization discontinuity at the interfaces. Our results provide a deeper insight into the photoinduced properties in the 2D electron gas system, paving the way for the design of oxide optoelectronic devices.
2. Using 1,1,1-Trichloroethane degradation data to understand NAPL dissolution and solute transport at real sites
Valeureux D Illy, Gregory J V Cohen, Elicia Verardo, Patrick Höhener, Nathalie Guiserix, Olivier Atteia J Contam Hydrol. 2022 Feb;245:103934.doi: 10.1016/j.jconhyd.2021.103934.Epub 2021 Dec 6.
Analytical and numerical models describing the evolution of contaminant concentrations in the plume associated with the dissolution of NAPL source and degradation processes were presented in the literature. At real sites and particularly in complex aquifers like chalk, it is difficult to understand how the sources of contaminants evolve with time. 1,1,1-Trichloroethane (1,1,1-TCA) is one of the few compounds with a well-known hydrolysis constant, that can help to improve knowledge of the contaminant sources and transport rates of dissolved contaminants in groundwater by dating the spill. In this work, different scenarios that could explain the evolution of the concentrations of 1,1,1-TCA and its degradation product 1,1-Dichloroethene (1,1-DCE) at a real contaminated site were investigated by analytical and numerical modelling. The results show that (1) the peaks of concentration time series do not correspond to a single contamination event even in the case of a complex medium, (2) the multiphasic behavior of the concentration time series is dictated by the dissolution in a heterogeneous medium, and (3) the persistence of the concentrations can arise from a small residual organic phase or transport in dual domain medium.
3. (1Z,3Z)-1,4-diphenyl-1,4-bis(p-tolylmethylthio)-1,3-butadiene
F Freeman, H Lu, J W Ziller, E Rodriguez Acta Crystallogr C. 1995 Apr 15;51 ( Pt 4):659-61.doi: 10.1107/s0108270194007845.
The crystal structure of (1Z,3Z)-1,4-diphenyl-1,4-bis-(p-tolylmethylthio)-1,3-b utadiene (1), C32H30S2, is described. Compound (1) has an s-trans conformation. The single bond length, C(2)--C(2'), in compound (1) of 1.432 (5) A is shorter than the C(3)--C(4) single bond (1.48 A) in 1,3-butadiene and the double-bond length, C(1)--C(2), of 1.350 (3) A in compound (1) is comparable to that in 1,3-butadiene (1.34 A). The short C--C single and double bonds in (1) may be attributed to delocalization (resonance) over the planar four-atom unit, hybridization changes, the presence of the S atoms, and/or other factors.
