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1.
Materials (Basel) ; 13(3)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31973194

RESUMO

In this work various amount of phosphomolybdic acid (PMo) were immobilized on amine functionalized SBA-15 and used as heterogeneous catalysts in the epimerization of glucose in aqueous solution. 13.3PMo/NH2-SBA-15 exhibited the best catalytic performance with a glucose conversion of 34.8% and mannose selectivity of 85.6% within two hours at 120 °C. The activation energy of 80.1 ± 0.1 kJ·mol-1 was lower than that of 96 kJ·mol-1 over the homogeneous H3PMo12O40 catalyst. The catalytic activities of 13.3PMo/NH2-SBA-15 for the transformation of some other aldoses including mannose, arabinose and xylose were also investigated.

2.
R Soc Open Sci ; 5(6): 180371, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30110402

RESUMO

A series of Ce x -V-g-C3N4 catalysts with different cerium content were synthesized by a facile co-assembly method. Compared with pure V-g-C3N4 catalyst, the addition of cerium facilitated the high dispersion of vanadium species as well as the benzene adsorption ability of the corresponding catalysts. Also, the existence of cerium promoted the partial reduction of vanadium species, which improved the redox property of vanadium species as the active centres. The Ce x -V-g-C3N4 catalysts showed considerably improved activity in the benzene hydroxylation reaction compared with V-g-C3N4 catalyst. Among the catalysts studied, Ce0.07-0.07 V-g-C3N4 exhibited the best catalytic activity with a benzene conversion of 33.7% and a phenol yield of 32.3% with good structural and catalytic stability, while only 24.7% of benzene conversion and phenol yield of 24.2% were obtained over 0.07 V-g-C3N4.

3.
Nanomaterials (Basel) ; 8(6)2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29895794

RESUMO

A series of composites consisting of g-C3N4 sheet and mesoporous Nb2O5 (mNb2O5) microsphere were fabricated by in situ hydrolysis deposition of NbCl5 onto g-C3N4 sheet followed by solvothermal treatment. The samples were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), N2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). The photocatalytic activity of the composites was studied by degradation of rhodamine B (RhB) and tetracycline hydrochloride (TC-HCl) in aqueous solution under visible light irradiation (λ > 420 nm). Compared with g-C3N4 and mNb2O5, g-C3N4-mNb2O5 composites have higher photocatalytic activity due to synergistic effect between g-C3N4 and mNb2O5. Among these composites, 4% g-C3N4-mNb2O5 has the highest efficiency and good recyclability for degradation of both RhB and TC-HCl.

4.
J Biosci Bioeng ; 126(1): 69-77, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29567373

RESUMO

Biomimetic mineralization has emerged as a novel tool for generating excellent supports for enzyme stabilization. In this work, protamine was used to induce titanium (IV) bis(ammonium lactato) dihydroxide (Ti-BALDH) into titania nanoparticles. This biomimetic titanification process was adopted for laccase immobilization. Laccase-biotitania biocatalyst was prepared and the effect of different parameters (buffer solution, titania precursor concentration, protamine concentration, and enzyme loading) on the encapsulation efficiency and recovery of laccase were evaluated. Compared with free laccase, the thermal and pH stability of immobilized laccase were improved significantly. In addition, laccase loaded on titania was effective at enhancing its storage stability. After seven consecutive cycles, the immobilized laccase still retained 51% of its original activity. Finally, laccase-biotitania biocatalysts showed good performance on decolorization of malachite green (MG), which can be attributed to an adsorption and degradation effect. The intermediates of the MG degradation were identified by gas chromatography-mass spectrometry (GC-MS) analysis, and the most probable degradation pathway was proposed. This study provides deeper understanding of the laccase-biotitania particles as a fast biocatalyst for MG decolorization.


Assuntos
Enzimas Imobilizadas/síntese química , Enzimas Imobilizadas/metabolismo , Lacase , Corantes de Rosanilina/isolamento & purificação , Titânio , Purificação da Água/métodos , Adsorção , Biocatálise , Cor , Enzimas Imobilizadas/química , Concentração de Íons de Hidrogênio , Lacase/síntese química , Lacase/química , Lacase/metabolismo , Nanopartículas/química , Corantes de Rosanilina/metabolismo , Titânio/química , Titânio/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
5.
PLoS One ; 12(3): e0172747, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28273118

RESUMO

Azo dyes are very resistant to light-induced fading and biodegradation. Existing advanced oxidative pre-treatment methods based on the generation of non-selective radicals cannot efficiently remove these dyes from wastewater streams, and post-treatment oxidative dye removal is problematic because it may leave many byproducts with unknown toxicity profiles in the outgoing water, or cause expensive complete mineralization. These problems could potentially be overcome by combining photocatalysis and biodegradation. A novel visible-light-responsive hybrid dye removal agent featuring both photocatalysts (g-C3N4-P25) and photosynthetic bacteria encapsulated in calcium alginate beads was prepared by self-assembly. This system achieved a removal efficiency of 94% for the dye reactive brilliant red X-3b and also reduced the COD of synthetic wastewater samples by 84.7%, successfully decolorized synthetic dye-contaminated wastewater and reduced its COD, demonstrating the advantages of combining photocatalysis and biocatalysis for wastewater purification. The composite apparently degrades X-3b by initially converting the dye into aniline and phenol derivatives whose aryl moieties are then attacked by free radicals to form alkyl derivatives, preventing the accumulation of aromatic hydrocarbons that might suppress microbial activity. These alkyl intermediates are finally degraded by the photosynthetic bacteria.


Assuntos
Fenômenos Fisiológicos Bacterianos , Biodegradação Ambiental , Corantes/metabolismo , Fotossíntese , Águas Residuárias/microbiologia , Catálise , Cromatografia Gasosa-Espectrometria de Massas
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 49(7): 591-4, 2015 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-26310469

RESUMO

OBJECTIVE: To investigate the quantity, quality and effect of health management service project for patients with hypertension and diabetes in basic public health service project of Sichuan province. METHODS: 44 health clinics or community health service center, 22 counties and 11 cities was extracted by method of multistage stratified sampling on March, 2014. In each institution we sampled 10 resident health record of hyperpietic and 10 of diabetic. Number of managed patients was recorded to calculate the rate of health management. Telephone survey was used to judge the accuracy and standardability of services the patients received according to the national basic public health service specifications. We compared the satisfaction rate and blood pressure/blood sugar control rate of patients which had accurate record to which had not, and which got normative services to which didn't. RESULTS: 33.8% (69 680/206 154) of the hyperpietics and 24.0% (25 562/106 508) of the diabetics were managed. 81.16% (702/865) of the records were with accurate information. 74.36% (522/702) of the patients received normative services. Blood pressure was well controlled in 86.92% (299/344) of the hyperpietics, and FPG was well controlled in 85.46% (288/337) of the diabetics. The satisfaction rate was 94.58% (698/738). The satisfaction rate of patients which had accurate record was 98.69% (677/686), but of which had not was just 40.38% (21/52) (χ² = 320.52, P < 0.001). The satisfaction rate of patients which got normative services was 99.22% (508/512), and of which did not get was 97.13% (169/174) (χ² = 2.92, P = 0.087). CONCLUSION: The quality of managed chronic patients was well, and got obvious effect. Measures need to implement for increasing the management rate, accuracy and standardability of health management services for hyperpietic and diabetic.


Assuntos
Serviços de Saúde Comunitária , Diabetes Mellitus , Gerenciamento Clínico , Hipertensão , Glicemia , China , Estudos Transversais , Humanos , Estados Unidos
7.
Materials (Basel) ; 8(4): 1545-1567, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-28788017

RESUMO

Organic-inorganic hybrid polyoxometalate (POM) compounds are a subset of materials with unique structures and physical/chemical properties. The combination of metal-organic coordination complexes with classical POMs not only provides a powerful way to gain multifarious new compounds but also affords a new method to modify and functionalize POMs. In parallel with the many reports on the synthesis and structure of new hybrid POM compounds, the application of these compounds for heterogeneous catalysis has also attracted considerable attention. The hybrid POM compounds show noteworthy catalytic performance in acid, oxidation, and even in asymmetric catalytic reactions. This review summarizes the design and synthesis of organic-inorganic hybrid POM compounds and particularly highlights their recent progress in heterogeneous catalysis.

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