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1.
J Wound Ostomy Continence Nurs ; 51(2): 111-116, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527319

RESUMO

PURPOSE: The primary aims of this study were to evaluate the prevalence of wound-related pain (WRP) in patients with chronic wounds and assess the use of pain relief measures. DESIGN: A cross-sectional study. SUBJECTS AND SETTING: A convenience sample of patients with chronic wounds was recruited from outpatient clinics of 12 hospitals covering 7 of 13 cities in the Jiangsu province located in eastern China from July 10 to August 25, 2020. The sample comprised 451 respondents, and their mean age was 54.85 (SD 19.16) years; 56.1% (253/451) patients were male. METHODS: An investigator-designed questionnaire was used to collect pain-related information from patients. The questionnaire consisted of 4 parts: (1) basic demographic and clinical information (patient and wound characteristics); (2) wound baseline pain; (3) wound-related procedural pain and pain relief method; and (4) the effect of WRP on the patient. Pain was assessed using the Numerical Rating Scale (NRS) scored from 0 (no pain) to 10 (worst pain). Severity of pain was based on NRS scores' classification as mild (1-3), moderate (4-6), and severe (7-10). The survey was conducted from July 10 to August 25, 2020. Participants were instructed on use of the NRS and then completed the questionnaire following dressing change independently. RESULTS: The 3 most common types of chronic wounds were traumatic ulcers, surgical wounds, and venous leg ulcers. The 3 most prevalent locations were lower limbs, feet, and thorax/abdomen. Of all patients, 62.5% (282/451) and 93.8% (423/451) patients experienced wound baseline pain and wound-related procedural pain, respectively. The mean score of wound baseline pain was 3.76 (SD 1.60) indicating moderate pain. During wound management, the highest pain score was 6.45 (SD 2.75) indicating severe pain; the most severe pain scores were associated with debridement. The use of drugs to relieve wound pain was low, while the use of nondrug-based analgesia was relatively high. Because of WRP, patients with chronic wounds feared dressing changes, hesitated to move, and showed a decline in sleep quality. CONCLUSIONS: Wound baseline pain and wound-related procedural pain were very common in patients with chronic wounds. In the future, targeted intervention plans should be developed by combining drug-based and nondrug-based analgesia according to pain severity.


Assuntos
Dor Processual , Úlcera Varicosa , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Estudos Transversais , Dor , Inquéritos e Questionários , Infecção da Ferida Cirúrgica
2.
Foods ; 13(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38397495

RESUMO

Brasenia schreberi J.F. Gmel (BS) is rich in mucilage, which has diverse biological activities, and is utilized in the food and pharmaceutical industries due to its nutritional value. Proteomics analysis was employed to investigate the cause of mucilage disappearance in BS and its effect on nutrient accumulation. Among the 2892 proteins identified, 840 differentially expressed proteins (DEPs) were found to be involved in mucilage development. By comparing the expression patterns and functions and pathway enrichment, the DEPs mainly contributed to carbon and energy metabolism, polysaccharide metabolism, and photosynthesis. Our study also revealed positive correlations between mucilage accumulation and tryptophan metabolism, with high levels of indole-3-acetic (IAA) contributing to mucilage accumulation. Furthermore, environmental changes and particularly excessive nutrients were found to be detrimental to mucilage synthesis. Overall, in the absence of various stimuli in the growing environment, BS accumulates more nutrients within the plant itself instead of producing mucilage.

3.
Sensors (Basel) ; 24(1)2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38203139

RESUMO

A novel label-free optical fiber biosensor, based on a microcavity fiber Mach-Zehnder interferometer, was developed and practically demonstrated for DNA detection. The biosensor was fabricated using offset splicing standard communication single-mode fibers (SMFs). The light path of the sensor was influenced by the liquid sample in the offset open cavity. In the experiment, a high sensitivity of -17,905 nm/RIU was achieved in the refractive index (RI) measurement. On this basis, the probe DNA (pDNA) was immobilized onto the sensor's surface using APTES, enabling real-time monitoring of captured complementary DNA (cDNA) samples. The experimental results demonstrate that the biosensor exhibited a high sensitivity of 0.32 nm/fM and a limit of detection of 48.9 aM. Meanwhile, the sensor has highly repeatable and specific performance. This work reports an easy-to-manufacture, ultrasensitive, and label-free DNA biosensor, which has significant potential applications in medical diagnostics, bioengineering, gene identification, environmental science, and other biological fields.


Assuntos
Engenharia Biomédica , Comércio , DNA Complementar , Fibras Ópticas
4.
Food Funct ; 14(8): 3564-3575, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36946057

RESUMO

Ulcerative colitis (UC) is a growing health concern in humans, but it can be prevented by using special dietary strategies. Young stems and leaves of Brasenia schreberi (BS) are coated with a special polysaccharide hydrogel (BS mucilage) which can be beneficial for colon health. The aim of this study was to investigate the preventive effects of BS mucilage against UC in a DSS-treated mouse model. Although containing only 0.3% solid content, our research showed that BS mucilage effectively attenuated the disease activity index (DAI) and the spleen index and downregulated IL-1ß, IL-18, IL-6 and CAT mRNA levels in DSS-treated mice, which is a promising UC alleviation function. Additionally, BS mucilage also improved the propionate and butyrate levels in mouse feces and alleviated the imbalanced gut microbiota induced by DSS. The abundance of pro-inflammatory and colorectal cancer related bacteria, such as Prevotella, Ruminococcus, Acutalibacter and Christensenella, was decreased by BS mucilage feeding, whereas the abundance of anti-inflammatory and SCFA-producing bacteria including Alistipes and Odoribacter was increased. In conclusion, the current study shows that the daily consumption of BS mucilage could be an effective way to prevent UC in mice, via modulation of gut microbiota.


Assuntos
Colite Ulcerativa , Colite , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Colite Ulcerativa/induzido quimicamente , Hidrogéis , Colo , Polissacarídeos/farmacologia , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Colite/induzido quimicamente , Camundongos Endogâmicos C57BL
5.
Int Wound J ; 20(6): 1903-1910, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36526600

RESUMO

Chronic wounds are very common wound types in clinics which have a prolonged and painful healing process. Chronic wounds affect health-related quality of life (HRQoL) on patients. However, there is no specific instrument to measure the HRQoL in Chinese patients with chronic wounds. Wound-QoL is a questionnaire targeted the experience of health-related life to patients with chronic wounds. The study aims to translate and cross-culturally adapt the Wound-QoL into Chinese and to evaluate its psychometric properties (validity, reliability, floor, and ceiling effect) in a convenience sample of 203 Chinese outpatients with chronic wounds. Reliability was good, with internal consistency of 0.798-0.960 and test-retest reliability of 0.720-0.838. Criterion-related validity was assessed by the correlation coefficient between Wound-QoL and generic European QoL instrument- EQ-5D-5L, which was found statistically significant (P<.001). No signs of floor or ceiling effect could be detected. Further, confirmatory factor analysis (CFA) was used to verify the reliability and validity of the instrument in this study. In conclusion, the Chinese Wound-QoL is a valid and reliable tool for measuring HRQoL in populations with chronic wounds.


Assuntos
Psicometria , Qualidade de Vida , Ferimentos e Lesões , Humanos , População do Leste Asiático/psicologia , Reprodutibilidade dos Testes , Inquéritos e Questionários , Ferimentos e Lesões/psicologia
6.
Metabolism ; 144: 155376, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36521551

RESUMO

BACKGROUND: Renal interstitial fibrosis (RIF) is one of the main features of diabetic nephropathy (DN), but the molecular mechanisms mediating RIF in DN has yet been fully understood. S100A8 and S100A9 are the proteins associated with immune and inflammation response. Here we reported the expression of S100A8 and S100A9 were significantly increased on tubular epithelial cells in diabetic kidneys through a proteomic analysis. METHODS: We detected the expression of S100A8/A9 in diabetic kidneys by using immunoblotting, real-time PCR and immunostaining. RNA silencing and overexpression were performed by using S100A8/A9 expression/knockdown lentivirus to investigate the connection between S100A8/A9 and epithelial to mesenchymal transition (EMT) process. We also identify the expression of TLR4/NFκB pathway-related molecules in the case mentioned above. Afterwards a CO-IP assay was used to verify that compound AB38b ameliorates the EMT by interfering S100A8/A9 expression. RESULTS: The expression of S100A8 and S100A9 were significantly increased on tubular epithelial cells in diabetic kidneys. S100A8/A9 knocking-down alleviate and over-expression promote the renal interstitial fibrosis of diabetic mice. Mechanically, high levels of S100A8/A9 expression in tubular epithelial cells during diabetic condition activated the TLR4/NF-κB signal pathway which promoted the EMT process and finally led to RIF progression. S100A8/A9 knockdown ameliorated RIF of diabetic mice. Further experiments revealed that compound AB38b inhibited the EMT progression of tubular epithelial cells induced by S100A8/A9 through interfering the expressions of S100A8/A9. CONCLUSIONS: Our study suggest that abnormal expression of S100A8/A9 in the disease condition promotes EMT process and RIF through TLR4/NF-κB signal pathway. Using small molecular inhibitor AB38b to inhibit the abnormal expressions of S100A8/A9 might be a novel therapeutic strategy in treating DN.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Camundongos , Animais , Nefropatias Diabéticas/metabolismo , NF-kappa B/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Transição Epitelial-Mesenquimal , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Proteômica , Calgranulina A/genética , Calgranulina A/metabolismo , Calgranulina B/genética , Calgranulina B/metabolismo , Fibrose
7.
Biochem Pharmacol ; 192: 114675, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252407

RESUMO

Podocyte injury following abnormal podocyte autophagy plays an indispensable role in diabetic nephropathy (DN), therefore, restoration of podocyte autophagy is considered as a feasible strategy for the treatment of DN. Here, we investigated the preventive effects of sarsasapogenin (Sar), the main active ingredient in Anemarrhena asphodeloides Bunge, on the podocyte injury in diabetic rats, and tried to illustrate the mechanisms underlying the effects in high glucose (HG, 40 mM)-treated podocytes (MPs). Diabetes model was established in rats with single streptozocin (60 mg· kg-1) intraperitoneal administration. The rats were then treated with Sar (20, 60 mg· kg-1· d-1, i.g.) or a positive control drug insulin (INS) (40 U· kg-1· d-1, i.h.) for 10 weeks. Our results showed that both Sar and insulin precluded the decreases of autophagy-related proteins (ATG5, Beclin1 and LC3B) and podocyte marker proteins (podocin, nephrin and synaptopodin) in the diabetic kidney. Furthermore, network pharmacology was utilized to assess GSK3ß as the potential target involved in the action of Sar on DN and were substantiated by significant changes of GSK3ß signaling in the diabetic kidney. The underlying protection mechanisms of Sar were explored in HG-treated MPs. Sar (20, 40 µM) or insulin (50 mU/L) significantly increased the expression of autophagy- related proteins and podocyte marker proteins in HG-treated MPs. Furthermore, Sar or insulin treatment efficiently regulatedphosphorylation at activation and inhibition sites of GSK3ß. To sum up, this study certifies that Sar meliorates experimental DN through targeting GSK3ß signaling pathway and restoring podocyte autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Nefropatias Diabéticas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Glicogênio Sintase Quinase 3 beta/metabolismo , Podócitos/efeitos dos fármacos , Espirostanos/administração & dosagem , Animais , Autofagia/fisiologia , Nefropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Masculino , Podócitos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
8.
Front Pharmacol ; 12: 792777, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069207

RESUMO

Podocytes injury is one of the leading causes of proteinuria in patients with diabetic nephropathy (DN), and is accompanied by podocytes apoptosis and the reduction of podocyte markers such as synaptopodin and nephrin. Therefore, attenuation of podocyte apoptosis is considered as an effective strategy to prevent the proteinuria in DN. In this study, we evaluated the anti-podocyte-apoptosis effect of quercetin which is a flavonol compound possessing an important role in prevention and treatment of DN and verified the effect by using db/db mice and high glucose (HG)-induced mouse podocytes (MPs). The results show that administration of quercetin attenuated the level of podocyte apoptosis by decreasing the expression of pro-apoptotic protein Bax, cleaved caspase 3 and increasing the expression of anti-apoptotic protein Bcl-2 in the db/db mice and HG-induced MPs. Furthermore, epidermal growth factor receptor (EGFR) was predicted to be the potential physiological target of quercetin by network pharmacology. In vitro and vivo experiments confirmed that quercetin inhibited activation of the EGFR signaling pathway by decreasing phosphorylation of EGFR and ERK1/2. Taken together, this study demonstrates that quercetin attenuated podocyte apoptosis through inhibiting EGFR signaling pathway, which provided a novel approach for further research of the mechanism of quercetin in the treatment of DN.

9.
Front Med (Lausanne) ; 8: 719958, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047519

RESUMO

Objective: To identify novel immune-related genes expressed in primary Sjögren's syndrome (pSS). Methods: Gene expression profiles were obtained from the Gene Expression Omnibus (GEO) database, and differentially expressed genes (DEGs) were screened. The differences in immune cell proportion between normal and diseased tissues were compared, weighted gene co-expression network analysis was conducted to identify key modules, followed by a protein-protein interaction (PPI) network generation and enrichment analysis. The feature genes were screened and verified using the GEO datasets and quantitative real-time PCR (RT-qPCR). Results: A total of 345 DEGs were identified, and the proportions of gamma delta T cells, memory B cells, regulatory T cells (Tregs), and activated dendritic cells differed significantly between the control and pSS groups. The turquoise module indicated the highest correlation with pSS, and 252 key genes were identified. The PPI network of key genes showed that RPL9, RBX1, and RPL31 had a relatively higher degree. In addition, the key genes were mainly enriched in coronavirus disease-COVID-2019, hepatitis C, and influenza A. Fourteen feature genes were obtained using the support vector machine model, and two subtypes were identified. The genes in the two subtypes were mainly enriched in the JAK-STAT, p53, and toll-like receptor signaling pathways. The majority of the feature genes were upregulated in the pSS group, verified using the GEO datasets and RT-qPCR analysis. Conclusions: Memory B cells, gamma delta T cells, Tregs, activated dendritic cells, RPL9, RBX1, RPL31, and the feature genes possible play vital roles in the development of pSS.

10.
Oncol Lett ; 20(4): 74, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32863907

RESUMO

Hepatocellular carcinoma (HCC) is a malignant tumor with high incidence and high risk. Study of the role and mechanism of miRNAs are a hot spot of research providing new treatment ideas in malignant tumors. The effect of miR-642a on HCC progression and the underlying molecular mechanism were investigated. Expression of miR-642a and SEMA4C was measured by western blot analysis and RT-PCR. miR-642a expression was elevated while SEMA4C expression was attenuated in HCC tissues and cells. Results of luciferase reporter and western blot analyses show that miR-642a modulated SEMA4C expression by binding to its 3'UTR. Moreover, miR-642a negatively regulated SEMA4C expression. HCC cell migration and invasion was tested by Transwell assays. The findings revealed that the number of migrated and invaded cells were reduced by miR-642a mimic and raised by miR-642a inhibitor, indicating that miR-642a showed a suppression effect on HCC cell migration and invasion. Additionally, the migration and invasion of HCC cells were inhibited by SEMA4C siRNA, and SEMA4C reversed miR-642a effect on HCC migration and invasion. Furthermore, p38 MAPK signaling pathway was proven to be inhibited by miR-642a mimic, whereas facilitated by miR-642a inhibitor and SEMA4C siRNA could overturn the promotion effect of miR-642a inhibitor. Briefly, miR-642a targeted SEMA4C to repress HCC cell migration and invasion through p38 MAPK signaling pathway providing a new strategy for treatment of HCC patients.

11.
Nanomaterials (Basel) ; 10(4)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32235628

RESUMO

Bi(NO3)3·5H2O and (NH4)6Mo7O24·4H2O were used as precursors to synthesize flaky γ-Bi2MoO6 samples by a hydrothermal method, and Pt/γ-Bi2MoO6 samples with different mass fractions were prepared by an NaBH4 reduction method. Alpha alkylation of benzyl alcohol and acetophenone with photocatalysts under visible light irradiation was performed, and the activity of 4 wt % Pt/γ-Bi2MoO6 (γ-Bi2MoO6 was prepared by a nitric acid method, pH = 9, and reaction temperature 180 °C) was the best. The photocatalytic reaction conditions were optimized by changing various kinds of variables, such as the type of catalyst, solvent, and base, and the amount of base, catalyst, and reactant. The optimal conditions for the organic reaction were 75 mg 4 wt % Pt/γ-Bi2MoO6, 6 mL n-heptane, 1.2 mmol NaOH, 1 mmol acetophenone, and 3 mmol benzyl alcohol. Under the optimal reaction conditions, the effects of different light wavelengths and light intensities on the reaction were measured, and the cycling ability of the photocatalyst was tested. After five cycles, the photochemical properties of the catalyst were relatively stable. Finally, the active substances were identified (such as electrons (e-), holes (h+), hydroxyl radicals (•OH), and superoxide radicals (•O2-).

12.
Appl Opt ; 57(9): 2033-2039, 2018 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-29603990

RESUMO

In this work, a high-sensitivity and low-cost sensing scheme for measuring intrinsic and induced fiber birefringence change is reported based on a polarimetric fiber laser sensor interrogated by the beat frequency technique. The fiber birefringence measurement is achieved by an external applied strain method. A detailed theoretical analysis of the principle for fiber birefringence measurement is carried out. Two alternative equations are given for determining the change of fiber birefringence, which make it very convenient for users to choose different order beat signals. To verify the performance of the sensing system, the external applied strain-induced fiber birefringence change is measured experimentally. The experiment result shows that the fiber birefringence experiences a linear increase with the increase of applied strain. A strain response coefficient of 4.646×10-11/µÏµ is obtained. Furthermore, the repeatability and stability performances of the polarimetric fiber laser sensor are also investigated.

13.
Opt Lett ; 42(1): 159-162, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28059203

RESUMO

The Letter describes a hybrid multiplexing scheme for a multi-longitudinal-mode fiber laser sensor array by combining wavelength-division multiplexing and frequency-division multiplexing techniques. The proposed multiplexing system consists of many subgroups, each of which has many fiber laser sensors with approximately equal laser-operating wavelengths but different cavity lengths. Each sensor in one subgroup can be interrogated by using frequency-division multiplexing technology because of different sensors with different beat frequencies. For different subgroups, they are characteristic of different laser-operating wavelengths. Each subgroup can be divided into the designed channel by dense wavelength-division multiplexers. At last, a 4×4 sensor multiplexing system was experimentally validated. The strain or temperature applied on each sensor was successfully extracted. The proposed multiplexing system provides a dramatic increase in the number of multiplexed sensors. It greatly reduces the weight, volume, and cost of each sensor and offers a competitive solution for a large-scale monitoring system.

14.
Mol Biotechnol ; 58(11): 729-737, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27696215

RESUMO

It remains an unsolved problem to quantify a natural microbial community by rapidly and conveniently measuring multiple species with functional significance. Most widely used high throughput next-generation sequencing methods can only generate information mainly for genus-level taxonomic identification and quantification, and detection of multiple species in a complex microbial community is still heavily dependent on approaches based on near full-length ribosome RNA gene or genome sequence information. In this study, we used near full-length rRNA gene library sequencing plus Primer-Blast to design species-specific primers based on whole microbial genome sequences. The primers were intended to be specific at the species level within relevant microbial communities, i.e., a defined genomics background. The primers were tested with samples collected from the Daqu (also called fermentation starters) and pit mud of a traditional Chinese liquor production plant. Sixteen pairs of primers were found to be suitable for identification of individual species. Among them, seven pairs were chosen to measure the abundance of microbial species through quantitative PCR. The combination of near full-length ribosome RNA gene library sequencing and Primer-Blast may represent a broadly useful protocol to quantify multiple species in complex microbial population samples with species-specific primers.


Assuntos
Primers do DNA/genética , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico/genética , Análise de Sequência de RNA/métodos , Microbiologia de Alimentos , Biblioteca Gênica , Metagenoma , RNA Bacteriano/genética , Especificidade da Espécie
15.
Chemosphere ; 164: 421-429, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27599008

RESUMO

In order to improve the electro-catalytic activity and catalytic reaction rate of graphite-like material, Tin dioxide-Titanium dioxide/Nano-graphite (SnO2-TiO2/Nano-G) composite was synthesized by a sol-gel method and SnO2-TiO2/Nano-G electrode was prepared in hot-press approach. The composite was characterized by X-ray photoelectron spectroscopy, fourier transform infrared, Raman, N2 adsorption-desorption, scanning electrons microscopy, transmission electron microscopy and X-ray diffraction. The electrochemical performance of the SnO2-TiO2/Nano-G anode electrode was investigated via cyclic voltammetry and electrochemical impedance spectroscopy. The electro-catalytic performance was evaluated by the degradation of ceftriaxone sodium and the yield of ·OH radicals in the reaction system. The results demonstrated that TiO2, SnO2 and Nano-G were composited successfully, and TiO2 and SnO2 particles dispersed on the surface and interlamination of the Nano-G uniformly. The specific surface area of SnO2 modified anode was higher than that of TiO2/Nano-G anode and the degradation rate of ceftriaxone sodium within 120 min on SnO2-TiO2/Nano-G electrode was 98.7% at applied bias of 2.0 V. The highly efficient electro-chemical property of SnO2-TiO2/Nano-G electrode was attributed to the admirable conductive property of the Nano-G and SnO2-TiO2/Nano-G electrode. Moreover, the contribution of reactive species ·OH was detected, indicating the considerable electro-catalytic activity of SnO2-TiO2/Nano-G electrode.


Assuntos
Ceftriaxona/química , Técnicas Eletroquímicas , Grafite/química , Compostos de Estanho/química , Titânio/química , Catálise , Eletrodos , Espectroscopia Fotoeletrônica , Difração de Raios X
16.
J Hazard Mater ; 315: 1-10, 2016 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-27149660

RESUMO

Nano-graphite(Nano-G)/TiO2 composite photoelectrode was fabricated via sol-gel reaction, followed by the hot-press approach. The morphology, structure and light absorption capability of composite was characterized by various characterizations. The photoelectrochemical property and photoelectrocatalytic(PEC) activity of photoelectrode were also investigated. Results revealed that anatase TiO2 nanoparticles with an average diameter of 10nm were dispersed uniformly on the thickness of 2-3nm Nano-G, and TiOC bond was formed. The absorption edge of Nano-G/TiO2 photoelectrode was red-shifted towards low energy region and the enhanced visible light absorption was obtained. The charge transfer resistance of Nano-G/TiO2 photoelectrode was significantly decreased after the addition of Nano-G. And its transient photoinduced current was 10.5 times the value achieved using TiO2 electrode. Nano-G/TiO2 photoelectrode displayed greatly enhanced PEC activity of 99.2% towards the degradation of phenol, which was much higher than the 29.1% and 58.3% degradation seen on TiO2 and Nano-G electrode, respectively. The highly efficient and stable PEC activity of Nano-G/TiO2 photoelectrode was attributed to the synergy effect between photocatalysis and electrocatalysis, as well as enhanced light absorption ability and higher separation efficiency of photogenerated charge carriers. Moreover, contribution of series of reactive species to the PEC degradation of Nano-G/TiO2 photoelectrode was determined.

17.
ChemSusChem ; 9(10): 1118-24, 2016 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-27111114

RESUMO

A novel 3 D mesoporous black TiO2 (MBT)/MoS2 /MBT sandwich-like nanosheet was successfully fabricated using a facile mechanochemical process combined with an in situ solid-state chemical reduction approach, followed by mild calcination (350 °C) under an argon atmosphere. The MBT/MoS2 /MBT exhibits a 3 D sandwich-like nanosheet structure and heterojunctions are formed at the interfaces between MoS2 and black TiO2 . The significantly narrowed band gap of MBT/MoS2 /MBT is attributed to the introduction of MoS2 and the formed Ti(3+) species in the frameworks. The visible-light photocatalytic degradation rate of methyl orange and the hydrogen production rate are as high as 89.86 % and 0.56 mmol h(-1) g(-1) , respectively. The introduction of MoS2 and Ti(3+) in the frameworks favors the visible-light absorption and the separation of photogenerated charges, and the 3 D sandwich-like heterojunction structure facilitates the transfer of photogenerated charges.


Assuntos
Dissulfetos/química , Luz , Molibdênio/química , Nanoestruturas/química , Processos Fotoquímicos , Titânio/química , Adsorção , Compostos Azo/química , Compostos Azo/isolamento & purificação , Catálise , Hidrogênio/química , Porosidade
18.
J Nanosci Nanotechnol ; 15(7): 4920-5, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26373057

RESUMO

CeO2/nanographite (CeO2/nano-G) composite materials were got by chemical precipitation method with nanographite (nano-G) and cerous nitrate hexahydrate as raw materials. The microstructures of CeO2/nano-G composite materials were characterized by means of SEM, XRD, XPS and Raman. The cathodes were made by nano-G and CeO2/nano-G composite materials, respectively. The electrolysis phenol was conducted by the diaphragm cell prepared cathode and the Ti/RuO2 anode. The results indicated that the Cerium oxide is mainly in nanoscale spherical state, uniformly dispersed in the nanographite sheet surface, and there are two different oxidation states for elemental Ce, namely, Ce(III) and Ce(IV). In the diaphragm electrolysis system with the aeration conditions, the degradation rate of phenol reached 93.9% under 120 min's electrolysis. Ceria in the cathode materials might lead to an increase in the local oxygen concentration, which accelerated the two-electron reduction of O2 to hydrogen peroxide (H2O2). The removal efficiency of phenol by using the CeO2/nano-G composite cathode was better than that of the nano-G cathode.

19.
J Nanosci Nanotechnol ; 14(9): 6835-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924338

RESUMO

Mn/nanographite (nano-G) materials were got by chemical redox reaction and using nano-G, potassium permanganate and manganese acetate as raw materials. The microstructures and properties of nano-G and Mn/nano-G sheets were characterized by means of SEM, XPS, XRD and Raman. The results showed that manganese oxide nanoscale rod inlaid on the graphite layer surface, the manganese valence of Mn/nano-G was +4 and existed in the form of the mix crystal of α-MnO2 and γ-MnO2. Moreover, Mn/nano-G represented the preferable electro-catalysis performance. The electrolysis of phenol was conducted by using self-made cathode and the Ti/IrO2/RuO2 anode in the diaphragm cell. In the diaphragm electrolysis system with the aeration conditions, under 120 min's electrolysis, the degradation rate of 100 mg/L phenol of Mn/nano-G cathode reached 97.2%. Compared with the nano-G cathode, the Mn/nano-G had higher catalytic activity and better degradation rate of phenolic organics.

20.
J Nanosci Nanotechnol ; 13(8): 5580-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23882798

RESUMO

Highly ordered TiO2 nano-tube arrays (TNTAs) photoelectrodes were prepared through anodization method, followed by annealing treatment. Morphologies and structures of the as-prepared TNTAs samples were investigated through scanning electron microscopy (SEM) and X-ray diffraction (XRD). In addition, the optical and photoelectrochemical (PECH) properties were investigated through ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS) and transient photocurrent response. Furthermore, the photodecomposition performances were investigated through the yield of hydroxyl (*OH) radicals and photocatalytic (PC) degradation of RhB under Xenon light irradiation. Results indicated that the TNTAs samples annealed at 723 K exhibited the highest photocurrent response, PC performance and yield of *OH radicals, in which 60.8% of RhB could be degraded by PC degradation within 60 min. The high PC performance could mainly be attributed to the anatase structure, high crystallinity and highly ordered nano-tubular structure, which favored the transfer and separation of photoinduced charge carriers. This study suggests that highly ordered nano-structure could provide superior pathway for the charge transfer and separation.

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