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1.
Front Chem ; 6: 518, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30416996

RESUMO

In this study, flower-like AgI/BiOCOOH heterojunctions were constructed through a two-step procedure involving the solvothermal synthesis of BiOCOOH microflowers followed by AgI modification using a precipitation method. These novel photocatalysts were systematically examined by XRD, UV-vis DRS, SEM, TEM, EDS, and PL spectroscopy techniques. The AgI/BiOCOOH heterojunction were studied as a decent photocatalyst for the removal of the industrial dye (rhodamine B, and methyl blue) and antibiotic (tetracycline) under visible light. The AgI/BiOCOOH heterojunctions are much more active than bare BiOCOOH, and AgI, which could be ascribed to the improved separation of charge carriers, resulting from the formation of p-n heterojunction between two constituents. The holes (h+) and superoxide radical (•O 2 - ) were detected as the main active species responsible for the pollutant degradation. The results showed that a highly efficient visible-light-driven photocatalytic system was developed for the decomposition of toxic pollutants.

2.
Nanomaterials (Basel) ; 8(11)2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30405012

RESUMO

The development of excellent full-spectrum photocatalysts is of vital significance to its practical application in environmental remediation. Herein, flower-like Ag2CO3/BiOCOOH type I heterostructures were prepared via a facile method and exhibited powerful photocatalytic activity by removing various toxic pollutants (rhodamine B, methyl blue, and tetracycline hydrochloride) under simulated sunlight irradiation. The boosted photocatalytic performance is attributed to the expanded range of the absorption spectrum and alleviated separation rate of the photo-induced electrons and holes. The photoluminescence spectra and trapping experiment were applied to clarify the photocatalytic reaction mechanism of Ag2CO3/BiOCOOH. The holes and •O2- were detected as the dominant reactive species involved in pollutant degradation. This work provides a novel full-spectrum-driven photocatalyst of Ag2CO3/BiOCOOH, which could effectively degrade toxic pollutants under simulated sunlight.

3.
J Colloid Interface Sci ; 530: 171-178, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29982008

RESUMO

One of the great challenges in the field of photocatalysis is to develop novel photocatalysts with excellent solar-light-harvesting capacity and separation efficiency of photo-induced charge. Herein, novel CeO2/Bi2MoO6 heterojunctions were fabricated through in-situ precipitation of CeO2 nanoparticles (size: ∼26 nm) on the surface of flower-like Bi2MoO6 superstructures (diameter: 2.1-3.5 µm) by a simple method. The as-prepared photocatalysts were systematically characterized by a range of techniques. The photocatalytic degradation of rhodamine B (RhB) dye, methyl orange (MO) dye and tetracycline (TC) antibiotic by this novel photocatalyst was investigated under visible-light irradiation. The CeO2/Bi2MoO6 heterojunction with a CeO2/Bi2MoO6 weight ratio of 0.05 (0.05Ce-Bi) exhibited the highest photocatalytic activity with the RhB degradation efficiency of 100% in 75 min, which was considerably higher than those of pristine CeO2 (26.8%) and Bi2MoO6 (80.3%) as well as their physical mixtures (74.8%). The more efficient separation of electron-hole pairs was identified as the primary reason of the enhanced photocatalytic activity. Moreover, the synthesized material maintained satisfactory activity even after 6 recycling runs, indicating its high photocatalytic stability. Therefore, our finding offers a new avenue for development of stable and efficient heterojunction photocatalysts for environmental purification.

4.
Front Chem ; 6: 255, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30013966

RESUMO

Semiconductor-based photocatalysis is of great potential for tackling the environmental pollution. Herein, a novel hierarchical heterostructure of Bi2O2CO3 micro-flowers in-situ decorated with Ag3VO4 nanoparticles was developed by a facile method. Various characterization techniques have been employed to study the physical and chemical property of the novel catalyst. The novel catalyst was utilized for the photocatalytic removal of industrial dyes (rhodamine B, methyl orange) and tetracycline antibiotic under visible-light irradiation. The results indicated that Ag3VO4/Bi2O2CO3 heterojunctions showed a remarkably enhanced activity, significantly higher than those of bare Ag3VO4, Bi2O2CO3, and the physical mixture of Ag3VO4 and Bi2O2CO3 samples. This could be ascribed to an enhanced visible-light harvesting capacity and effective separation of charge carriers by virtue of the construction of hierarchical Ag3VO4/Bi2O2CO3 heterojunction. Moreover, Ag3VO4/Bi2O2CO3 also possesses an excellent cycling stability. The outstanding performance of Ag3VO4/Bi2O2CO3 in removal of toxic pollutants indicates the potential of Ag3VO4/Bi2O2CO3 in real environmental remediation. Highlights Novel architectures of Ag3VO4 nanoparticles modified Bi2O2CO3 micro-flowers were constructed.Novel Ag3VO4/Bi2O2CO3 exhibited excellent photocatalytic activity and stability.Ag3VO4/Bi2O2CO3 heterojunctions significantly promote the charge separation.

5.
Beilstein J Nanotechnol ; 9: 1308-1316, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29765809

RESUMO

To develop efficient and stable visible-light-driven (VLD) photocatalysts for pollutant degradation, we synthesized novel heterojunction photocatalysts comprised of AgI nanoparticle-decorated Ag2WO4 nanorods via a facile method. Various characterization techniques, including XRD, SEM, TEM, EDX, and UV-vis DRS were used to investigate the morphology and optical properties of the as-prepared AgI/Ag2WO4 catalyst. With AgI acting as the cocatalyst, the resulting AgI/Ag2WO4 heterostructure shows excellent performance in degrading toxic, stable pollutants such as rhodamine B (RhB), methyl orange (MO) and para-chlorophenol (4-CP). The high performance is attributed to the enhanced visible-light absorption properties and the promoted separation efficiency of charge carriers through the formation of the heterojunction between AgI and Ag2WO4. Additionally, AgI/Ag2WO4 exhibits durable stability. The active species trapping experiment reveals that active species (O2•- and h+) dominantly contribute to RhB degradation. The AgI/Ag2WO4 heterojunction photocatalyst characterized in this work holds great potential for remedying environmental issues due to its simple preparation method and excellent photocatalytic performance.

6.
J Colloid Interface Sci ; 521: 42-49, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29549764

RESUMO

A huge challenge in the field of pollutant removal is the scarcity of visible-light-driven (VLD) photocatalysts that are efficient, stable, easily recyclable and capable of mineralizing organic pollutants. In this regard, a novel hierarchical architecture of Bi2MoO6 nanosheets onto NiTiO3 nanofibers for tetracycline hydrochloride (TC) removal was rationally designed and fabricated via a facile approach. In this heterojunction system, highly homogeneous-distributed Bi2MoO6 nanosheets were anchored on electrospun NiTiO3 nanofibers, endowing the heterojunction with compact interfacial contact. By virtue of the favorable interfacial contact and matched band alignment, promoted suppression of photo-generated electron-hole recombination is achieved in Bi2MoO6/NiTiO3 system, as confirmed by photoluminescence measurement. As a result, the heterojunction with Bi2MoO6/NiTiO3 molar ratio of 1:1 exhibits an outstanding VLD photocatalytic activity and good stability for tetracycline hydrochloride (TC) degradation. The photodegradation rate constant (k) is 26.0, 5.4 or 3.7 folds higher than that of pristine NiTiO3, Bi2MoO6, or the mechanical mixture (20.2 wt% NiTiO3 + 79.8 wt% Bi2MoO6). The holes and superoxide radicals are detected as the dominant active species responsible for TC removal. Moreover, this work reports an efficient VLD photocatalyst for TC removal and will open up new insights into the design of novel fiber-shaped VLD heterojunction photocatalyts for environment remediation.

7.
Prion ; 7(4): 335-40, 2013 Jul-Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23924638

RESUMO

The objective of the present study was to systematically explore the effects of 32K Da protein (32KP) on postmenopausal osteoporosis. Eighty 3-mo-old female Sprague-Dawley rats were employed and randomly divided into one sham-operated group (SHAM) and five ovariectomy (OVX) subgroups as OVX (control), OVX with 17-ethinylestradiol (E2, 25 g/kg/day), OVX with 32KP of graded doses (50, 50, or 150 mg/kg/day). 32KP or E2 diet was fed on week 4 after operation, for 16 weeks. Bone mass, bone turnover and strength were evaluated by dual-energy X-ray absorptiometry (DEXA), biochemical markers and three-point bending test, respectively. Femur marrow cavity was observed by light microscopy via hematoxylin-eosin staining. It is observed that different dosage treatment of 32KP increased the body weight and prevented the loss of bone mass induced by OVX. The prevention effect against bone loss was presumably due to the altering of the rate of bone remodeling. The bone mineral density and bone calcium content in OVX rats were lower than that in the control group, suggesting that 32KP was able to prevent significant bone loss. In addition, the data from three point bending test and femur sections showed that 32KP treatment enhanced bone strength and reduced the marrow cavity of the femur in OVX rats. In the serum and urine assay, 32KP decreased urinary deoxypyridinoline and calcium concentrations; however, serum alkaline phosphatase activities were not inhibited. It suggested that amelioration of bone loss was changed via inhibition of bone reabsorption. Our findings indicated that 32KP might be a potential alternative drug for the prevention and treatment of postmenopausal osteoporosis.


Assuntos
Remodelação Óssea/efeitos dos fármacos , Fêmur/metabolismo , Osteoporose/tratamento farmacológico , Ovariectomia , Proteínas de Plantas/farmacologia , Rumex/química , Absorciometria de Fóton , Animais , Cálcio/sangue , Cálcio/urina , Feminino , Fêmur/diagnóstico por imagem , Osteoporose/sangue , Osteoporose/diagnóstico por imagem , Osteoporose/urina , Proteínas de Plantas/química , Ratos , Ratos Sprague-Dawley
8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 29(4): 350-3, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23643163

RESUMO

OBJECTIVE: To construct and identify the recombinant adenovirus of muramidase-released protein (MRP) gene fragment from Streptococcus suis type 2 (SS2). METHODS: The specific primers were designed based on the sequence of MRP gene fragment. The MRP gene fragment (467-1351 bp) was amplified by PCR method with genomic DNA of SS2 as a template. PCR products were cloned in pMD18-T vector. Then MRP gene fragment was linked into the adenovirus shuttle plasmid (pShuttle-CMV) to construct recombinant shuttle plasmid (pShuttle-CMV-MRP). After PmeI digestion, it was transformed into BJ5183-AD-1 competent cells containing adenoviral backbone plasmid pAdEasy-1 to construct homogeneous recombinant adenovirus plasmid (pAdeno-CMV-MRP). Then the recombinant adenovirus plasmid was linearized by PmeI and then transfected into AD-293 cells for viral packaging. Finally, the virus liquid was tested by PCR and Western blotting. RESULTS: Cytopathic effect (CPE) was observed at 8 d after transfection of linear pAdeno-CMV-MRP in AD-293 cells. MRP gene fragment and protein expression were also detected in the virus liquid. CONCLUSION: The recombinant adenovirus of MRP gene fragment (rAdeno-MRP) from SS2 was constructed successfully.


Assuntos
Adenoviridae/genética , Adenoviridae/metabolismo , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Streptococcus suis/genética , Streptococcus suis/metabolismo , Linhagem Celular , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Humanos , Plasmídeos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Transfecção/métodos
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