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With the purpose of searching novel, green and energetic oxidants, polynitro-acetone, polynitro-dimethyl ether, and polynitro-dimethylamine are designed as potential powerful oxidants and energetic materials in this work. Their optimized molecular geometries and electronic structures are calculated using density functional theory at m062x/6-311G++(d,p) level. Based on these results, heat of formation (HOF), detonation energy (Q), detonation velocity (D), and detonation pressure (P) are further evaluated. It is found that the oxygen-rich and chlorine-free compounds with 5 to 6 NO2 groups in molecule can be used as the potential energetic oxidants with high oxygen balance, while those with 3 to 4 NO2 groups are suitable for high-density energetic materials. Furthermore, stability correlations of all the compounds are established according to calculated bond order, natural bond orbital (NBO), bond dissociation enthalpies (BDE), and energy gaps (ΔELUMO–HOMO). Finally, burning rate is also calculated to show their potential application as oxidants in propellants. [ABSTRACT FROM AUTHOR]

Theeffect of sodium dodecyl sulfate (SDS) on the poly(N-isopropylacrylamide) (PNIPAM) tethered to nanoparticles was experimentallyinvestigated using dynamic light scattering below the lower criticalsolution temperature. A mean-field analytical model was used to calculatethe parameters of interfacial PNIPAM–SDS complexes. Particularly,the magnitude of SDS adsorption energy obtained decreases with decreasingexcluded volume parameter, implying that the partially collapsed PNIPAMbrush virtually favors the adsorption of SDS onto the PNIPAM chains.A self-consistent field theory (SCFT) model was used to get a detailedquantitative description of monomer density distribution. By loweringthe solvent quality, a number of phenomena related to the noncontinuityof monomer density are revealed. These phenomena are either referredto as the vertical phase separation or as its precursor, which canbe delayed and eventually eliminated as the SDS coverage is increased.The distribution of free chain ends was calculated using the SCFTmodel. Increasing the SDS coverage gives rise to a broader and moreasymmetric distribution of free chain ends, accompanied by a considerableexpansion of the dead zone (below which the free chain ends do notexist), but lowering the solvent quality has opposite influences.The relative thickness of the dead zone can be scaled to a mastercurve, regardless of SDS coverage. [ABSTRACT FROM AUTHOR]

Abstract: Here, we report the fabrication of a well inter-grown ZIF-8 membrane on coarse α-Al2O3 support via a two-step hydrothermal synthesis method. The ZIF-8 seeds were initially vacuum seeded to ensure overall coverage of the voids on the α-Al2O3 support followed by hydrothermally treated twice for forming well inter-grown membrane. The presence of sodium formate was found to be of critical importance to enable the growth of ZIF-8 structure into a continuous membrane. This method enabled our ZIF-8 membrane to exhibit CO2 permeance of 3.49×10−7 mol/m2 sPa with significant CO2/N2 and CO2/CH4 selectivity of 3.4 and 4.0, respectively. [Copyright &y& Elsevier]

• Direct electrochemical C2 phosphonylation of thiazole derivatives under mild conditions. • The avoidance of external metal, additive and chemical-oxidant. • Facile access to various phosphorus compounds containing multi heteroatoms. • An atom economic system with simple operation and wide substrate scope. We herein report a direct electrochemical dehydrogenative C H phosphonylation of thiazoles derivatives with H 2 evolution. Employing electricity as the green and sole oxidant, cheap metal as electrode, the anodic oxidation together with cathodic hydrogen evolution process provides a green and efficient strategy for C H phosphonylation. A diverse range of phosphorus products were constructed under external metal and oxidant-free conditions at ambient temperature, featuring atom economy, simple operation and wide reaction scope. [Display omitted] [ABSTRACT FROM AUTHOR]

Zeolite W membranes were grown on their seed pellets prepared via a straightforward vacuum filtration method followed by crystallization, rendering them self-supported. Herein, the feasible application of self-supported zeolite W membranes for CO2/CH4 separation with astonishing CO2/CH4 selectivity was demonstrated. [ABSTRACT FROM AUTHOR]