磷酸铜锆催化剂上醇选择性氧化（英文）

The catalytic activity of copper zirconium phosphate(ZPCu) in the selective oxidation of alcohols to their corresponding ketones or aldehydes, using H2O2 as an oxidizing agent, was studied. The oxida‐tion reaction was performed without any organic solvent, phase‐transfer catalyst, or additive. Steric factors associated with the substrates influenced the reaction. The catalyst was characterized using X‐ray diffraction, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, and scanning electron microscopy. It was shown that the interlayer distance increased from 0.74 to 0.80 nm and the crystallinity was reduced after Cu2+ intercalation into the layers. This catalyst can be recovered and reused three times without significant loss of activity and selectivity.     

Cu-based atom transfer radical polymerization of methyl methacrylate using a novel tridentate ligand with mixed donor atoms

This study is aimed at atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) using a novel catalyst. The bis-(2-dodecylsulfanyl-ethyl)-amine (SNS) tridentate ligand with mixed donor atoms was synthesized in high purity using inexpensive reagents and was reacted with copper(I) bromide to produce the CuBr/SNS catalyst. The catalyst mediated living polymerization of MMA yielding polymers with controlled molecular masses and narrow molecular mass distributions (PDI < 1.25). Also, the kinetic plot exhibited a linear increase of ln([M]₀/[M]) versus time, indicating constant concentration of propagating radicals during the polymerization. The products were characterized by ¹H NMR, ¹³C NMR, FT-IR, UV-VIS, GC and elemental analyses (CHNS) and by GPC.     

Study of Tangle on the Three Qubit Werner States by Using of Twirl Operation

International Journal of Theoretical Physics - In this paper we study the Tangle of three qubit Werner state using Twirl operation and association scheme. To do this, we introduce the invariants of...     

Syntheses,crystal structures and solvatochromic properties of dinuclear oxalato-bridged copper(II) complexes

Three dinuclear copper(II) complexes, [Cu₂(L¹)₂(μ-ox)](ClO₄)₂?2(CH₃CN), [Cu₂(L²)₂(μ-ox)](ClO₄)₂?H₂O, and [Cu₂(L³)₂(μ-ox)](ClO₄)₂ where ox = oxalato; L = N,N-dimethyl,N′-benzylethane-1,2-diamine, L¹, N,N-diethyl,N′-benzylethane-1,2-diamine, L², N,N-diisoprophyl,N′-benzylethane-1,2-diamine, L³, were prepared and characterized by elemental analyses, spectral (IR, UV–Vis) data and molar conductance measurements. The crystal structures of [Cu₂(L¹)₂(μ-ox)](ClO₄)₂?2(CH₃CN) and [Cu₂(L³)₂(μ-ox)](ClO₄)₂ have been determined by single-crystal X-ray analysis. Solvatochromic behaviors were investigated in various solvents, showing positive solvatochromism. The effect of steric hindrance around the copper ion imposed by N-alkyl groups of the diamine chelates on the solvatochromism property of the complexes is discussed. Solvatochromism was also studied with different solvent parameter models using stepwise multiple linear regression method.     

Simulation of conjugate radiation–forced convection heat transfer in a porous medium using the lattice Boltzmann method

In this paper, a lattice Boltzmann method is employed to simulate the conjugate radiation–forced convection heat transfer in a porous medium. The absorbing, emitting, and scattering phenomena are fully included in the model. The effects of different parameters of a silicon carbide porous medium including porosity, pore size, conduction–radiation ratio, extinction coefficient and kinematic viscosity ratio on the temperature and velocity distributions are investigated. The convergence times of modified and regular LBMs for this problem are 15 s and 94 s, respectively, indicating a considerable reduction in the solution time through using the modified LBM. Further, the thermal plume formed behind the porous cylinder elongates as the porosity and pore size increase. This result reveals that the thermal penetration of the porous cylinder increases with increasing the porosity and pore size. Finally, the mean temperature at the channel output increases by about 22% as the extinction coefficient of fluid increases in the range of 0–0.03.

     

The selective aerobic oxidation of methylaromatics to benzaldehydes using a unique combination of two heterogeneous catalysts

A unique combination of a supported cobalt complex and the first example of supported NHPI in acetic acid gives a surprisingly stable heterogeneous catalytic system for the selective aerobic oxidation of methylaromatics to benzaldehydes at atmospheric pressure.     

Synthesis of Some Novel γ-Spirolactones

Summary. We report on the addition of dialkyl acetylenedicarboxylate to 1-alkylisatins or tryptanthrine in the presence of triphenylphosphine which leads to highly functionalised novel unsaturated -spirolactones.