[Progress in synaptic mechanism in epileptogenesis].

Recurrent seizures lead to abnormal expression of synaptic proteins, reorganization of synapse and formation of abnormal neuron network. Recently, it is identified that the synaptic proteins are involved in epileptogenesis. The abnormal expression of several synaptic regulatory proteins and postsynaptic membrane receptor proteins may result in epilepsy. The ion channels usually are the action target of most antiepileptic drugs. However, carbamazepine and zonisamide may interact with syntaxin and/or soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex to exert its function of anti-epilepsy. The synaptic vesicle protein 2A is the action target for new anti-epileptic drugs, including levetiracetam, brivaracetam and seletracetam.

Nitrogen-doped hollow carbon spheres with tunable shell thickness for high-performance supercapacitors.

Nitrogen-doped hollow carbon spheres (NHCSs) are well prepared by using Cu2O microspheres as a hard template and 3-aminophenol formaldehyde resin polymer as carbon and nitrogen precursors. The thickness of the carbon shell can be easily controlled in the range of 15-84 nm by simply adjusting the weight ratios of the precursors to Cu2O microspheres, and the Cu2O templates can also be further reused. Physicochemical characterization demonstrates that the obtained NHCSs possess a well-developed hollow spherical structure, thin carbon shell and high nitrogen doping content. Due to these characteristics, when further utilized as electrodes for supercapacitors, the NHCSs with the carbon shell thickness of 15 nm show a high capacitance of 263.6 F g-1 at 0.5 A g-1, an outstanding rate performance of 122 F g-1 at 20 A g-1 and an excellent long-term cycling stability with only 9.8% loss after 1000 cycles at 5 A g-1 in 6 M KOH aqueous electrolyte. This finding may push forward the development of carbon materials, exhibiting huge potential for electrochemical energy storage applications.

Photoluminescence enhancement effect of CeO2 in rare earth composites MM'O3/CeO2 and MM'O3/CeO2: Pr(3+) (M = Ca, Sr; M' = Ti, Zr).

In the context, a modified sol-gel technology was afford to the synthesis of rare earth composite ceramic phosphors MM'O(3)/CeO(2) and MM'O(3)/CeO(2): Pr(3+) (M = Ca, Sr; M' = Ti, Zr) with multicomponent hybrid precursors were composed. The micromorphology, particle size and photoluminescence properties were studied with XRD, SEM and luminescent spectroscopy in detail. Both XRD and SEM indicated the particle sizes were in the submicrometer range of 100-300 nm. The photoluminescence for these ceramic phosphors were studied in details with the different component of host (molecular ratio of Sr, Ca and Ti, Zr), presenting a broad spectral band in the visible blue-violet region with the maximum excitation peak at 449 nm and a wide emission range with a maximum peak at 619 nm, which was ascribed to be the characteristic transition of Pr(3+) ((1)D(2) --> (3)H(4)). These phosphors can be expected for visible light conversion (blue --> red) materials. Especially it can be found that the introduction of CeO(2) can enhance the luminescence intensity of MM'O(3) and MM'O(3): Pr(3+).

Photocatalytic degradation of C.I. Direct Red 23 in aqueous solutions under UV irradiation using SrTiO3/CeO2 composite as the catalyst.

The photocatalytic degradation of C.I. Direct Red 23 (4BS) in aqueous solutions under UV irradiation was investigated with SrTiO3/CeO2 composite as the catalyst. The SrTiO3/CeO2 powders had more photocatalytic activity for decolorization of 4BS than that of pure SrTiO3 powder under UV irradiation. The effects of catalytic dose, pH value, initial concentration of dye, irradiation intensity as well as scavenger KI were ascertained, and the optimum conditions for maximum degradation were determined. Under the irradiation of a 250 W mercury lamp, the best catalytic dose was 1.5 g/L and the best pH was 12.0. Light intensity exhibited a significant positive effect on the efficiency of decolorization, whereas the initial dye concentration showed a significant negative effect. Under the conditions of a catalytic dose of 1.5 g/L, pH of 12.0, initial dye concentration of 100mg/L, light intensity of 250 W, and air flow rate of 0.15 m3/h, complete decolorization, as determined by UV-visible analysis, was achieved in 60 min, corresponding to a reduction in chemical oxygen demand (COD) of 69% after a 240 min reaction. A tentative degradation pathway based on the sensitization mechanism of photocatalysis is proposed.

Hydrothermal Synthesis, Microstructure and Photoluminescence of Eu-Doped Mixed Rare Earth Nano-Orthophosphates.

Eu(3+)-doped mixed rare earth orthophosphates (rare earth = La, Y, Gd) have been prepared by hydrothermal technology, whose crystal phase and microstructure both vary with the molar ratio of the mixed rare earth ions. For La(x)Y(1-x)PO(4): Eu(3+), the ion radius distinction between the La(3+) and Y(3+) is so large that only La(0.9)Y(0.1)PO(4): Eu(3+) shows the pure monoclinic phase. For La(x)Gd(1-x)PO(4): Eu(3+) system, with the increase in the La content, the crystal phase structure of the product changes from the hexagonal phase to the monoclinic phase and the microstructure of them changes from the nanorods to nanowires. Similarly, Y(x)Gd(1-x)PO(4): Eu(3+), Y(0.1)Gd(0.9)PO(4): Eu(3+) and Y(0.5)Gd(0.5)PO(4): Eu(3+) samples present the pure hexagonal phase and nanorods microstructure, while Y(0.9)Gd(0.1)PO(4): Eu(3+) exhibits the tetragonal phase and nanocubic micromorphology. The photoluminescence behaviors of Eu(3+) in these hosts are strongly related to the nature of the host (composition, crystal phase and microstructure).

Mechanism of the photocatalytic degradation of C.I. Reactive Black 5 at pH 12.0 using SrTiO3/CeO2 as the catalyst.

The photocatalytic degradation mechanism of an azo dye, C.I. Reactive Black 5 (RB5), has been investigated in an aqueous suspension of SrTiO3/CeO2 composite under 250 W UV irradiation at pH 12.0. The process was studied by monitoring the change in RB5 concentration and the intermediate products employing UV-visible spectrophotometry, ion chromatography (IC), and gas chromatography/ mass spectrometry (GC/MS) techniques and depletion in total organic carbon (TOC) content as a function of irradiation time. The adsorption peaks at wavelengths of 600, 312, and 254 nm were identified as the chromophore structure, and the naphthalene and benzene components of RB5, respectively. Little influence of iodide ion, tert-butyl alcohol, fluoride ion, or persulfate ion as h(vb)+, *OH, or e(cb)- scavengers on the decolorization proved that the decolorization of RB5 primarily proceeded by photolysis and/or O2*- in the bulk solution. After the decolorization, the process could shift progressively from the bulk solution to the surface of the catalysts and cleavage of the naphthalene and benzene rings was mainly attributed to the h(vb)+ pathway and *OH(ads) reactions, which was further verified by the effect of scavengers.