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2.
Nanomaterials (Basel) ; 12(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35889549

RESUMO

Flexible pressure sensors still face difficulties achieving a constantly adaptable micronanostructure of substrate materials. Interlinked microcone resistive sensors were fabricated by polydimethylsiloxane (PDMS) nanocone array. PDMS nanocone array was achieved by the second transferring tapered polymethyl methacrylate (PMMA) structure. In addition, self-assembly 2D carbon nanotubes (CNTs) networks as a conducting layer were prepared by a low-cost, dependable, and ultrafast Langmuir−Blodgett (LB) process. In addition, the self-assembled two-dimensional carbon nanotubes (CNTs) network as a conductive layer can change the internal resistance due to pressure. The results showed that the interlinked sensor with a nanocone structure can detect the external pressure by the change of resistivity and had a sensitive resistance change in the low pressure (<200 Pa), good stability through 2800 cycles, and a detection limit of 10 kPa. Based on these properties, the electric signals were tested, including swallowing throat, finger bending, finger pressing, and paper folding. The simulation model of the sensors with different structural parameters under external pressure was established. With the advantages of high sensitivity, stability, and wide detection range, this sensor shows great potential for monitoring human motion and can be used in wearable devices.

3.
Materials (Basel) ; 14(23)2021 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-34885540

RESUMO

Resistive pressure sensors are appealing due to having several advantages, such as simple reading mechanisms, simple construction, and quick dynamic response. Achieving a constantly changeable microstructure of sensing materials is critical for the flexible pressure sensor and remains a difficulty. Herein, a flexible, tunable resistive pressure sensors is developed via simple, low-cost microsphere self-assembly and graphene/carbon nanotubes (CNTs) solution drop coating. The sensor uses polystyrene (PS) microspheres to construct an interlocked dome microstructure with graphene/CNTs as a conductive filler. The results indicate that the interlocked microdome-type pressure sensor has better sensitivity than the single microdome-type and single planar-type without surface microstructure. The pressure sensor's sensitivity can be adjusted by varying the diameter of PS microspheres. In addition, the resistance of the sensor is also tunable by adjusting the number of graphene/CNT conductive coating layers. The developed flexible pressure sensor effectively detected human finger bending, demonstrating tremendous potential in human motion monitoring.

4.
Chem Commun (Camb) ; 57(40): 4910-4913, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-33870994

RESUMO

There has been great demand for high-efficiency, low-cost, and abundant photoelectrode materials for photoelectrochemical (PEC) systems. Here, we studied the PEC performance of ternary sulfide photoelectrodes (ZnIn2S4 and CuInS2) with the same nanostructure and applied bidirectional p-n heterojunctions with energy levels that were well matched to the unassisted tandem PEC cell device. Moreover, ZnIn2S4/CuInS2 and CuInS2/ZnIn2S4 were used as a photoanode and photocathode, respectively, in the unassisted tandem PEC cell device, which achieved a relatively high photocurrent density of 0.06 mA cm-2. This work provides new ideas for the design and manufacture of high-efficiency unassisted tandem PEC cell devices.

5.
ChemSusChem ; 12(14): 3286-3295, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31140747

RESUMO

The construction of junctions on hematite is an effective way to overcome the problems of slow charge separation and transfer kinetics, but constructing the junction is a significant challenge in photoelectrochemical (PEC) water splitting. Herein, a considerable improvement in PEC performance for α-Fe2 O3 was achieved following the introduction of a p-n homojunction between n-type α-Fe2 O3 and p-type Ca-doped α-Fe2 O3 through a facile hydrothermal method. The resultant 3D branched Ca-Fe2 O3 /Fe2 O3 enhanced the absorption intensity and reached a photocurrent density of 2.14 mA cm-2 at 1.23 V vs. reversible hydrogen electrode (RHE). The merit of the desired lattice matching of the buried p-n homojunction structure built an internal electric field, which led to appropriate band alignment. These results were supported by a series of photoelectrochemical measurements, in particular, surface photovoltage (SPV) measurements. For further improvement of the charge-separation efficiency, a combination of separated cocatalysts was established on the homojunction structure, in which Pt acted as the electron collector and was deposited on the bottom, and Co-Pi as the hole-extraction cocatalyst was inserted to accelerate hole transfer on the surface of the photoanode. The resulting Co-Pi/Ca-Fe2 O3 /Fe2 O3 /Pt branched nanorods showed a significant improvement in charge-separation efficiency and photocurrent density (2.94 mA cm-2 at 1.23 V vs. RHE). The present strategy, both the construction of the p-n homojunction and the coupling electron- and hole-transfer cocatalyst, could be expanded to many unstable or low-efficiency semiconductors for the design and fabrication of cost-effective photoanodes in PEC water splitting.

6.
Materials (Basel) ; 12(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682779

RESUMO

In this paper, Au nanoshell arrays, serving as a photo-activated material, are fabricated via the combination of self-assembled nanosphere lithography and the thermal decomposing polymer method. The intensity and position of surface plasmonic resonance can be tuned from the visible region to the near-infrared region by changing the size of Au nanoshell arrays. When resonance absorption peaks of metal nanoparticles are matched with emission wavelengths of core-shell CdSe/CdS quantum dots, fluorescent intensity of CdSe/CdS quantum dots can be strongly enhanced. The physical mechanism of fluorescent enhancement is explained.

7.
Materials (Basel) ; 11(11)2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30463186

RESUMO

In this paper, a simple, inexpensive, and rapid method for the fabrication of controlled layer candle soot film has been reported by interface self-assembly and transferred method. The mechanism of candle soot self-assembly is explained and their morphology, elemental composition, optical, and wetting properties are characterized. The uniformity and thickness of prepared films especially depend on the concentration of candle soot mixed solution (alcohol and deionized water). The results show that the optimal concentration of candle soot solution is approximately ~0.2% wt/mL. In addition, the absorption spectra of the controlled-layer candle soot films are determined by the number of layers and the surface morphology. The hydrophobic properties of candle soot films are closely related to their layer number. When these films reach to the fourth layer, the water contact angle and roll-off angle are measured as 142° ± 2° and 6°, respectively. The controlled assembly CS films have the potential application in photo/electrocatalysis, solar cells, lithium-ion batteries, and water splitting.

8.
Biosci Rep ; 36(5)2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27582508

RESUMO

Sex determining region Y-box protein 12 (SOX12) is essential for embryonic development and cell fate determination. The role of SOX12 in tumorigenesis of breast cancer is not well-understood. Here, we found that SOX12 mRNA expression was up-regulated in human breast cancer tissues. To clarify the roles of SOX12 in breast cancer, we used lentiviral small hairpin RNAs (shRNAs) to suppress its expression in two breast cancer cells with relatively higher expression of SOX12 (BT474 and MCF-7). Our findings strongly suggested that SOX12 was critical for cell migration and invasion of breast cancer cells. We found that silencing of SOX12 significantly decreased the mRNA and protein levels of MMP9 and Twist, while notably increased E-cadherin. Moreover, SOX12 knockdown significantly inhibited the proliferation of breast cancer cells in vitro and the growth of xenograft tumors in vivo Flow cytometry analysis revealed that breast cancer cells with SOX12 knockdown showed cell cycle arrest and decreased mRNA and protein levels of PCNA, CDK2 and Cyclin D1. Taken together, SOX12 plays an important role in growth inhibition through cell-cycle arrest, as well as migration and invasion of breast cancer cells.

9.
Phys Chem Chem Phys ; 17(46): 30993-8, 2015 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-26553746

RESUMO

We report a novel promising quaternary sulfide (CuAgInS) to serve as a semiconductor sensitizer material in the photoelectrochemical field. In this study, CuAgInS (CAIS) sulfide sensitized ZnO nanorods were fabricated on ITO substrates through a facile and low-cost hydrothermal chemical method and applied on photoanodes for solar cells for the first time. The component and stoichiometry were key factors in determining the photoelectric performance of CAIS sulfide, which were controlled by modulating their reaction time. ZnO/Cu0.7Ag0.3InS2 nanoarrays exhibit an enhanced optical and photoelectric performance and the power conversion efficiency of ITO/ZnO/Cu0.7Ag0.3InS2/P3HT/Pt solid-state solar cell was up to 1.80%. The remarkable performance stems from improved electron transfer, a higher efficiency of light-harvesting and appropriate band gap alignment at the interface of the ZnO/Cu0.7Ag0.3InS2 NTs. The research indicates that CAIS as an absorbing material has enormous potential in solar cell systems.

10.
J Nanosci Nanotechnol ; 15(2): 1704-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353718

RESUMO

Large area polystyrene sphere (PS) arrays with different diameters were prepared by an interface self-assembly method. The inter-particle spacing of PSs was reduced by O2-plasma treatment. When O2-plasma treatment time was long enough, the space of PS arrays could be relatively large. After deposition of Au film and removing the PS masks, we obtained the Au holes arrays instead of Au triangle arrays as normal. The period and the diameter of the hole arrays can be adjusted by the PS with different size and by the O2-plasma treatment time. Then their optical property can be tuned effectively due to the surface plasmon resonance on these structures.

11.
Chem Commun (Camb) ; 51(71): 13678-81, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26229993

RESUMO

We report a novel quaternary solid solution (Ag-Cu-Sb-S or ACSS) serving as a photo-absorber material in the photoelectrochemical field for the first time, and ZnO/ACSS nanoarrays exhibited a photocurrent density of 4.45 mA cm(-2). The research indicates that ZnO/ACSS composite structures have enormous potential in PEC hydrogen generation systems.

12.
Curr Microbiol ; 71(4): 465-70, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26088951

RESUMO

The aim of this paper is to develop a novel method to separate Microthrix parvicella (M. parvicella) filaments from activated sludge easily and quickly, as there are a few difficulties in the isolation of M. parvicella filaments, such as complicated isolation process, time consuming, etc. In this work, a series of hydrophobic plate with and without microchannels have been prepared for the separation of M. parvicella filaments. The results showed that the presence of microchannels and hydrophobic property of the hydrophobic plates affected the separation efficiency of M. parvicella significantly. The scanning electron microscope and Keyence Digital Microscope analysis results showed that the diameter of microchannels was similar to the width of M. parvicella filament, which was beneficial for the fastening of M. parvicella filaments on the plate. The hydrophobic property of the prepared plates was tested by contact angle of water droplets, and the results displayed that the polydimethylsiloxane (PDMS) plate possessed the highest contact angle compared with that of other plates, like polymethylmethacrylate, polystyrene plate, and PDMS plate with no hydrophobic microchannels. Thus, it was concluded that the high separation efficiency of PDMS plates to M. parvicella filaments was due to its best hydrophobic property.


Assuntos
Actinobacteria/isolamento & purificação , Técnicas Bacteriológicas/métodos , Esgotos/microbiologia , Interações Hidrofóbicas e Hidrofílicas , Microscopia
13.
J Thorac Dis ; 7(12): 2234-42, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26793345

RESUMO

BACKGROUND: To investigate the prevalence of and risk factors for leukopenia in tuberculosis patients and the impact of anti-tuberculosis regimens on the occurrence of leukopenia in newly treated tuberculosis patients. METHODS: A total of 1,904 tuberculosis patients were included in the study. A cross-sectional survey of the prevalence of leukopenia was initially conducted, and then factors influencing leukopenia were identified using Logistic regression analysis. Non-treatment factors influencing peripheral blood leukocyte counts were analyzed using univariate COX proportional hazards models. Covariate analysis was used to assess the independent effect of different anti-tuberculosis regimens on peripheral blood leukocyte counts. RESULTS: Being female, advanced age and longer duration of previous anti-tuberculosis treatment (>6 month) were risk factors for leukopenia in tuberculosis patients, while secondary pulmonary tuberculosis, higher body mass index (BMI: 24-27.9 kg/m(2)), and higher degree of education (senior high school or above) were protective factors. Gender, vegetable consumption, drinking, pulmonary infection, other chronic diseases, and use of antibiotics were significantly associated with the development of leukopenia in patients on anti-tuberculosis treatment. In tuberculosis patients treated with anti-tuberculosis regimens not containing antibiotics, peripheral blood leukocyte levels gradually declined with the prolongation of treatment duration. In tuberculosis patients treated with anti-tuberculosis regimens containing antibiotics, peripheral blood leukocyte levels showed a declining trend. CONCLUSIONS: Female patients, patients at advanced age and recurrent tuberculosis patients having longer previous anti-tuberculosis treatment are high-risk populations for leukopenia. Attention should be paid to the influence of vegetable consumption and drinking, co-morbidities and use of antibiotics during anti-tuberculosis treatment.

14.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(8): 1046-9, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24325051

RESUMO

OBJECTIVE: To observe the effect of Wenxin Granule (WG) on brain natriuretic peptide (BNP) and heart rate variability (HRV) of acute coronary syndrome (ACS) patients. METHODS: Totally 65 ACS patients were randomly assigned to the treatment group (35 cases) and the control group (30 cases). All patients were treated with routine therapies such as angiotensin conversing enzyme inhibitors (ACEI) and metoprolol. Those in the treatment group took WG, 9 g each time, three times daily. All were treated for 90 days. Plasma samples of BNP and HRV were determined before treatment and after treatment. RESULTS: There was no statistical difference in pre-treatment plasma BNP (P > 0.05). Plasma BNP significantly decreased after treatment in the two groups when compared with before treatment (P < 0.05). The decrease was more obvious in the treatment group (P < 0.05). There was no statistical difference in pre-treatment HRV (P > 0.05). Compared with before treatment in the same group, RMSSD, PNN50%, and high frequency (HF) obviously increased, while low frequency (LF) and LF/HF ratio significantly decreased in the two groups, showing statistical difference (P < 0.05). The aforesaid indices were obviously better in the treatment group than in the control group (P < 0.05). CONCLUSION: Additional administration of WG could improve short-term clinical prognosis by down-regulating plasma BNP level (via improving myocardial ischemia) and modulating HRV.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Peptídeo Natriurético Encefálico/sangue , Fitoterapia , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
15.
J Nanosci Nanotechnol ; 13(6): 4311-5, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23862492

RESUMO

Nanosphere lithography is an efficient way to fabricate metallic nanostructures with large area. This paper presents the fabrication of metallic hexagonal nano-pyramid arrays by two dimensional nanospheres lithography assisted with O2 plasma treatment. By O2 plasma treatment, the gap and diameter of nanospheres can be modulated. After electron beam deposition, we can fabricate similar nanostructures with different pyramid gap distances. This method may be an easy way to modulate the geometric parameters of nanostructures.

16.
Opt Express ; 20(11): 12133-46, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22714200

RESUMO

We theoretically study the plasmonic modes in metal-multi-insulator-metal (MMIM) waveguides. Two types of symmetric MMIM structures consisting of three insulators are investigated thoroughly. The effective refractive index, energy confinement, propagation length, and figure of merit are given in terms of geometric parameters. Due to the step index modulation, these properties of MMIM structures differ from the metal-insulator-metal (MIM) structure. Compared with the corresponding MIM structures, MMIM structures can possess either better energy confinement or larger propagation length, which depends on the geometric parameters and the index distribution. Propagation length of up to 10(3) µm and a figure of merit of up to 10(4) are observed for MMIM structure with core thickness of several hundred nanometers.


Assuntos
Desenho Assistido por Computador , Metais/química , Modelos Teóricos , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Simulação por Computador , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
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