Mechanism studies of thermolysis process in copolyamide 66 containing triaryl phosphine oxide

Thermolysis behavior of flame-retardant copolyamide 66 (FR-PA66) in the presence of triaryl phosphine oxide (TPO) has been studied using different techniques such as differential scanning calorimetry, thermal gravimetric analysis, Fourier transform-infrared spectroscopy, and gas chromatography–mass spectrometry. The results indicate that TPO extends the thermolysis time of FR-PA66, and improves the thermolysis temperature. A three-stage mechanism for the decomposition of FR-PA66 has been proposed in this article. In the first stage, cleavage of P–C bond takes place in FR-PA66, while in the second stage, cleavage of polyamide chain occurs mainly. In the third stage, formation of cyclic compounds proceeds along with the formation of carbonized protective layer on the degraded polymer.     

New possibilities for testing local realism in high energy physics

The three photons from the dominant ortho-positronium decay and two vector mesons from the η_c exclusive decays are found to be in tripartite and high-dimensional entangled states, respectively. These two classes of entangled states possess the Hardy type nonlocality and allow a priori for quantum mechanics vs local realism test via Bell inequalities. The experimental realizations are shown to be feasible, and a concrete scheme to fulfill the test in experiment via two-vector-meson entangled state is proposed.     

Synthesis of ZnO Photocatalysts Using Various Surfactants

Russian Journal of Physical Chemistry A - Zinc oxide (ZnO) nanostructured materials have received significant attention because of their unique physicochemical and electronic properties. In...     

Knockout reaction mechanism studied by 6He projectile

Knockout reaction experiment was carried out by using the ⁶He beams at 61.2 MeV/u impinging on a CH₂ target. The α core fragments at forward angles were detected in coincidence with the recoiled protons at larger angles. From this exclusive measurement the valence nucleon knockout mechanism and the core knockout mechanism can be distinguished by the relation between the polar angles of the core fragments and the recoiled protons, respectively. It is demonstrated that the core knockout mechanism may result in some strong contamination to the real invariant mass spectrum.

     

Dynamical behaviour of Liu system with time delayed feedback

This paper investigates the dynamical behaviour of the Liu system with time delayed feedback. Two typical situations are considered and the effect of time-delay parameter on the dynamics of the system is discussed. It is shown that the Liu system with time delayed feedback may exhibit interesting and extremely rich dynamical behaviour. The evolution of the dynamics is shown to be complex with varying time-delay parameter. Moreover, the strange attractor like ‘wormhole＇ is detected via numerical simulations.     

Study on hydrogen sulfide plasma passivation of 790-nm laser diode cavity surface

In order to improve the optical properties of the Ⅲ-Ⅴ laser diodes(LDs) by means of H2S plasma passivation technology,H2S plasma passivation treatment is performed on the GaAs(110) surface.The optimum passivation conditions obtained are 60-W radio frequency(RF)power and 20-min duration.So the laser cavity surfaces axe treated under the optimum passivation conditions.Consequently,compared with unpassivated lasers with only AR/HR-coatings,the catastrophic optical damage (COD) threshold value of the passivated lasers by H2S plasma treatment is increased by 33%,which is almost the same as that of (NH4)2Sx treatment.And the life-test experiment has demonstrated that this passivation method is more stable than(NH4)2Sx solution wet-passivated treatment.     

Efficient soluble polymer-supported sharpless alkene epoxidation catalysts

High chemical yields and good enantiomeric excesses are obtained by using soluble polymer-supported tartrate ester in the epoxidation of trans-hex-2-en-1-ol using Ti(OPri)4/tert-butyl hydroperoxide.