Lithium difluoro(oxalato)borate as an additive to suppress the aluminum corrosion in lithium bis(fluorosulfony)imide-based nonaqueous carbonate electrolyte

Journal of Solid State Electrochemistry - Lithium bis(fluorosulfony)imide (LiFSI) is a promising alternative lithium salt to replace lithium hexafluorophosphate (LiPF6) due to its high conductivity...     

Extraordinary transport behavior of gases in isothermally annealed poly(4‐methyl‐1‐pentene) membranes

Poly(4‐methyl‐1‐pentene) (PMP) membranes were modified through isothermal annealing to investigate the change of their crystalline structure and rigid and mobile amorphous fractions (RAF and MAF), assuming a three‐phase model, affected the gas transport behavior. The crystalline structure was characterized by wide‐angle X‐ray diffraction (WAXD) and small‐angle X‐ray scattering (SAXS) techniques, and the free volume properties were analyzed by positron annihilation lifetime spectroscopy. Compared with the pristine membrane, the annealed membranes show higher crystallinity; the crystals undergo partial structural change from form III to form I. The lamellar crystal thickness, rigid amorphous fraction thickness, and long period in the lamellar stacks increase with crystallinity. The annealed PMP membranes exhibit higher permeability due to the increase in larger size free volumes in MAF and higher selectivity due to the increase in smaller size free volumes in RAF, respectively. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2368–2376     

Synthesis and Herbicidal Activities of 3‐(4‐Chloro‐2‐fluoro‐5‐substituted phenyl)benzo[d][1,2,3]triazin‐4(3H)‐one Derivatives

A series of 3‐phenyl benzo[d][1,2,3]triazin‐4(3H)‐one derivatives were synthesized through the condensation of phenol E and alkyl (alkenyl, alkynyl) chlorides (bromides, iodide) or alkyl chloroacetates or N‐alkyl chloroacetamides using K₂CO₃ as the acid acceptor in N,N‐dimethylformamide. Phenol E was prepared from starting material, 5‐amino‐2‐chloro‐4‐fluorophenyl ethyl carbonate, in four steps involving in amidation, reduction, diazotization, and deprotecting‐group reaction. The herbicidal activities of the title compounds were tested against two dicotyledonous plants and two monocotyledonous plants, in which some of them exhibited high herbicidal activities against two dicotyledonous plants in preemergence and postemergence treatments. Moreover, when the dosage was decreased to 180 and 90 g/ha, compounds F1 , F8 , and F9 showed highly selective inhibitory activities against amaranth pigweed, alfalfa, asteraceae, field sowthistle, morning glory, purslane, and velvetleaf in postemergence treatment but had no herbicidal efficacy on rape except F1 , suggesting that it be possible to find a kind of herbicides to inhibit dicotyledonous weeds in the field of dicotyledonous crops with the same genus as aforementioned weeds.     

Lattice Boltzmann simulation of liquid–vapor system by incorporating a surface tension term

In this study,we investigate the pseudopotential multiphase model of lattice Boltzmann method(LBM)and incorporate a surface tension term to implement the particle interaction force.By using the Carnahan–Starling(CS)equation of state(EOS)with a proper critical pressure–density ratio,a density ratio over 160000 is obtained with satisfactory numerical stability.The added surface tension term offers a flexible choice to adjust the surface tension strength.Numerical tests of the Laplace rule are conducted,proving that smaller spurious velocity and better numerical stability can be acquired as the surface tension becomes stronger.Moreover,by wall adhesion and heterogeneous cavitation tests,the surface tension term shows its practical application in dealing with problems in which the surface tension plays an important role.     

An Unprecedented Two‐Fold Nested Super‐Polyrotaxane: Sulfate‐Directed Hierarchical Polythreading Assembly of Uranyl Polyrotaxane Moieties

The hierarchical assembly of well‐organized submoieties could lead to more complicated superstructures with intriguing properties. We describe herein an unprecedented polyrotaxane polythreading framework containing a two‐fold nested super‐polyrotaxane substructure, which was synthesized through a uranyl‐directed hierarchical polythreading assembly of one‐dimensional polyrotaxane chains and two‐dimensional polyrotaxane networks. This special assembly mode actually affords a new way of supramolecular chemistry instead of covalently linked bulky stoppers to construct stable interlocked rotaxane moieties. An investigation of the synthesis condition shows that sulfate can assume a vital role in mediating the formation of different uranyl species, especially the unique trinuclear uranyl moiety [(UO₂)₃O(OH)₂]²⁺, involving a notable bent [O=U=O] bond with a bond angle of 172.0(9)°. Detailed analysis of the coordination features, the thermal stability as well as a fluorescence, and electrochemical characterization demonstrate that the uniqueness of this super‐polyrotaxane structure is mainly closely related to the trinuclear uranyl moiety, which is confirmed by quantum chemical calculations.