Bi metal/oxygen-deficient BiO2-x with tetrahedral morphology and high photocatalytic activity.

Vacancy-rich materials with high photocatalytic activity are of great interest for pollutants removal and play a significant role in green chemistry. Herein, we successfully synthesized Bi/BiO2-x composite through hydrothermal route. In this case, the surface plasmon resonance effect of Bi and oxygen vacancies of BiO2-x collectively increase the removal rate of pollutants. More importantly, the Bi/BiO2-x composites have enhanced activity in the degradation of RhB, MO, BPA and CIP, and the reduction of Cr(VI) and PNA. Besides, an enhanced photocatalytic activity is due to the main reactive species of ·[Formula: see text] and h+ that is confirmed by trapping experiments and ESR analyses. The electronic structure and visible light harvesting of photocatalysts were measured and also theoretically calculated by using density functional theory and finite difference time domain calculations, DRS, VB x-ray photoelectron spectroscopy and Mott-Schottky plots, which allowed to propose a possible photocatalytic mechanism for the degradation process.

Flower-like Bi2SiO5/Bi4MoO9 heterostructures for enhanced photocatalytic degradation of ciprofloxacin.

Bi2SiO5/Bi4MoO9 photocatalysts with heterostructures were successfully prepared using a one-pot solvothermal route. The effect of the molybdenum source on composite formation is discussed. Under ultraviolet light irradiation, the Bi2SiO5/Bi4MoO9 heterojunction photocatalyst exhibited higher photocatalytic performance than Bi2SiO5 and Bi4MoO9 towards the degradation of ciprofloxacin (CIP). This dramatically enhanced photoactivity can be ascribed to the construction of a heterojunction interface between Bi2SiO5 and Bi4MoO9, which not only suppresses the recombination of photoexcited charge carriers but also enhances light absorption. In addition, from a practical point of view, the the effect of initial CIP concentration and coexisting ions on the photodegradation process using as-prepared Bi2SiO5/Bi4MoO9 heterojunction photocatalysts was explored. Trapping experiments demonstrate that photoexcited holes and superoxide radicals are the main active species in the photodegradation of CIP over Bi2SiO5/Bi4MoO9 heterojunctions. Meanwhile, the conduction band and valence band potentials of Bi2SiO5 and Bi4MoO9 were measured by density functional theory calculation, diffuse reflectance spectroscopy and Mott-Schottky curves. A possible photocatalytic mechanism for CIP degradation over the Bi2SiO5/Bi4MoO9 heterojunction is proposed.

Electrochemical hydrogen peroxide sensor based on carbon supported Cu@Pt core-shell nanoparticles.

The Cu@Pt/C nanocomposites have been synthesized via two-step reduction method. Electrochemical observations showed that the Cu@Pt/C had better electrocatalytic activity for the reduction of hydrogen peroxide than Pt/C, with a wide linear range between 0.50µM and 32.56mM, a high sensitivity of 351.3µAmM-1cm-2, and a low detection limit of 0.15µM (signal/noise=3). Furthermore, the sensor based on Cu@Pt/C has potential applications due to its excellent long-time stability, good reproducibility and acceptable selectivity.

Synthesis and Electrochemical Properties of Nano-VO2 (B).

The nano-VO2 (B) has been self-assembly synthesized by hydrothermal method using different templates, which may give them some interesting properties. The as-prepared samples were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the samples were investigated. The results show that the hexadecyltrimethyl ammonium bromide (CTAB) (soft template) was used to obtain the VO2 (B1) nanobelts. The flake graphite (hard template) was taken to get the VO2 (B2) nanosheets. The VO2 (B1) nanobelts have higher initial capacity to compare with VO2 (B2). But the VO2 (B2) nanosheets showed better cycling performance than that of VO2 (B1) nanobelts. The nano VO2 (B2) is a promising anode material for lithium ion battery application.

Baicalin Reverses Depressive-Like Behaviours and Regulates Apoptotic Signalling Induced by Olfactory Bulbectomy.

Apoptosis is thought to be involved in neurological disorders including major depression. In this study, we examined whether the polyphenolic compound baicalin could decrease apoptosis in the olfactory bulbectomy (OBX) depression rat model. OBX rats exhibited decreased performance in depression-like behavioural tests and showed evidence of increased oxidative stress, decreased synaptophysin expression, and hippocampal apoptosis. Treatment with baicalin (20 and 40 mg/kg) significantly reversed all of these changes. Baicalin modulated the levels or activity of malondialdehyde, superoxide dismutase, and glutathione peroxidase and prevented apoptotic protease-activating factor-1 expression, effectively suppressing caspase-mediated apoptosis signalling cascades. Our results demonstrate that baicalin has potent antidepressant activity, likely because of its ability to suppress apoptosis.

Antidepressant-like effects of salidroside on olfactory bulbectomy-induced pro-inflammatory cytokine production and hyperactivity of HPA axis in rats.

Salidroside (SA) is the primary bioactive marker compound in the standardized extracts from Rhodiola rosea. Although it has potential antidepressant activity in a rat behavioral despair model, the mechanisms of antidepressant effect for SA remain unclear. The objective of this study was to evaluate the antidepressant effects of SA and to discuss the potential mechanisms in olfactory bulbectomized (OBX) rats. SA of 20, 40 mg/kg (p.o.) for 2 weeks notably alleviated OBX-induced hyperactivity in open field test, decreased immobility time in TST and FST. Chronic treatment with SA could remarkably reduce TNF-α and IL-1ß levels in hippocampus. Western blot showed that SA could markedly increase glucocorticoid receptor (GR) and brain-derived neurotrophic factor (BDNF) expression in the hippocampus. Besides, SA could also attenuate corticotropin-releasing hormone (CRH) expression in hypothalamus, as well as reducing significantly the levels of serum corticosterone. In conclusion, this study demonstrated that OBX rats treated with SA could significantly improve the depressive-like behaviors. The antidepressant mechanisms of SA might be associated with its anti-inflammatory effects and the regulation of HPA axis activity. Reversal of abnormalities of GR may be partly responsible for those effects. These findings suggested that SA might become a beneficial agent to prevent and treat the depression.

Baicalin reverse AMPA receptor expression and neuron apoptosis in chronic unpredictable mild stress rats.

Changes of a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor expression could impacts the viability of neurons and brain levels of brain-derived neurotrophic factor (BDNF) expression in the key brain structures in the pathophysiology of depressive disorder. In the present study, chronic unpredictable mild stress (CUMS) degraded performance decreased AMPA receptor expression and increased neuron apoptosis. Treatment with baicalin (20, 40mg/kg) significantly reversed these changes. This study demonstrates that baicalin has potent antidepressant effect, likely through up-regulated the expression of AMPA receptor and suppression neuron apoptosis in CUMS-treated rats.

Preparation of SO4(2-)/TiO2-La2O3 solid superacid and its catalytic activities in acetalation and ketalation.

SO(4)(2-)/TiO(2)-La(2)O(3), a novel solid superacid, was prepared and its catalytic activities at different synthetic conditions are discussed with esterification of n-butanoic acid and n-butyl alcohol as probing reaction. The optimum conditions have also been found, mole ratio of n(La(3+)):n(Ti(4+)) is 1:34, the soaked consistency of H(2)SO(4) is 0.8 mol/L, the soaked time of H(2)SO(4) is 24 h, the calcining temperature is 480 degrees C, the calcining time is 3 h. Then it was applied in the catalytic synthesis of ten important ketals and acetals as catalyst and revealed high catalytic activity. Under these conditions on which the molar ratio of aldehyde/ketone to glycol is 1:1.5, the mass ratio of the catalyst used in the reactants is 0.5%, and the reaction time is 1.0 h, the yields of ketals and acetals can reach 41.4%-95.8%.

Synthesis of acetals and ketals catalyzed by tungstosilicic acid supported on active carbon.

Catalytic activity of activated carbon supported tungstosilicic acid in synthesizing 2-methyl-2-ethoxycarbonylmethyl- 1,3-dioxolane, 2,4-dimethyl-2-ethoxycarbonylmethyl-1,3-dioxolane, cyclohexanone ethylene ketal, cyclohexanone 1,2-propa- nediol ketal, butanone ethylene ketal, butanone 1,2-propanediol ketal, 2-phenyl-1,3-dioxolane, 4-methyl-2-phenyl-1,3-dioxolane, 2-propyl-1,3-dioxolane, 4-methyl-2-propyl-1,3-dioxolane was reported. It has been demonstrated that activated carbon supported tungstosilicic acid is an excellent catalyst. Various factors involved in these reactions were investigated. The optimum conditions found were: molar ratio of aldehyde/ketone to glycol is 1/1.5, mass ratio of the catalyst used to the reactants is 1.0%, and reaction time is 1.0 h. Under these conditions, the yield of 2-methyl-2-ethoxycarbonylmethyl-1,3-dioxolane is 61.5%, of 2,4-dimethyl- 2-ethoxycarbonylmethyl-1,3-dioxolane is 69.1%, of cyclohexanone ethylene ketal is 74.6%, of cyclohexanone 1,2-propanediol ketal is 80.1%, of butanone ethylene ketal is 69.5%, of butanone 1,2-propanediol ketal is 78.5%, of 2-phenyl-1,3-dioxolane is 56.7%, of 4-methyl-2-phenyl-1,3-dioxolane is 86.2%, of 2-propyl-1,3-dioxolane is 87.5%, of 4-methyl-2-propyl-1,3-dioxolane is 87.9%.