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1.
J Colloid Interface Sci ; 608(Pt 1): 504-512, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34626992

RESUMO

As a typical two-dimensional (2D) metal chalcogenides and visible-light responsive semiconductor, zinc indium sulfide (ZnIn2S4) has attracted much attention in photocatalysis. However, the high recombination rate of photogenerated electrons and holes seriously limits its performance for hydrogen production. In this work, we report in-situ photodeposition of Ni clusters in hierarchical ZnIn2S4 nanoflowers (Ni/ZnIn2S4) to achieve unprecedented photocatalytic hydrogen production. The Ni clusters not only provide plenty of active sites for reactions as evidenced by in-situ photoluminescence measurement, but also effectively accelerate the separation and migration of the photogenerated electrons and holes in ZnIn2S4. Consequently, the Ni/ZnIn2S4 composites exhibit good stability and reusability with highly enhanced visible-light hydrogen production. In particular, the best Ni/ZnIn2S4 photocatalyst exhibits an unprecedented hydrogen production rate of 22.2 mmol·h-1·g-1, 10.6 times that of the pure ZnIn2S4 (2.1 mmol·h-1·g-1). And its apparent quantum yield (AQY) is as high as 56.14% under 450 nm monochromatic light. Our work here suggests that depositing non-precious Ni clusters in ZnIn2S4 is quite promising for the potential practical photocatalysis in solar energy conversion.

2.
J Colloid Interface Sci ; 604: 131-140, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34271486

RESUMO

Gold nanoparticles (Au NPs) with surface plasmonic resonance (SPR) effect and excellent internal electron transfer ability have widely been combined with semiconductors for photocatalysis. However, the in-depth effects of Au NPs in multicomponent photocatalysts have not been completely understood. Herein, ternary titanium oxide-gold-cadmium sulfide (TiO2-Au-CdS, TAC) photocatalysts, based on hierarchical TiO2 inverse opal photonic crystal structure with different Au NPs sizes have been designed to reveal the SPR effect and internal electron transfer of Au NPs in the presence of slow photon effect. It appears that the SPR effect and internal electron transfer ability of Au NPs, depending on their sizes, play a synergistic effect on the photocatalytic enhancement. The ternary TAC-10 photocatalyst with ~ 10 nm Au NPs demonstrates an unprecedented hydrogen evolution rate of 47.6 mmolh-1g-1 under visible-light, demonstrating ~ 48% enhancement comparing to the sample without slow photon effect. In particular, a 9.83% apparent quantum yield under 450 nm monochromatic light is achieved for TAC-10. A model is proposed and finite-difference time-domain (FDTD) simulations reveal the size influence of Au NPs in ternary TAC photocatalysts. This work suggests that the rational design of bifunctional Au NPs coupling with slow photon effect could largely promote hydrogen production from visible-light driven water splitting.

3.
Medicine (Baltimore) ; 100(10): e24910, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33725849

RESUMO

RATIONALE: Ocular metastasis of renal cell carcinoma (RCC) is rare, and mainly located on the choroid. We report a choroidal metastasis from RCC, which was recorded by a smartphone with an interface eyepiece adapter mounted on a slit lamp. PATIENT CONCERNS: A 45-year-old female presented with 1-month history of painless occlusion of the vision field on the left eye, who had undergone right nephrectomy for RCC 19 months ago. DIAGNOSES: A smooth, hemispherical and brown protrusion was found behind the pupil nasally. An enhanced computed tomography scan of the orbit showed a slightly high-density hemispherical nodule involving the nasal portions of the left eyeball, the enhancement of the lesion was obvious and homogeneous. A metastatic choroidal space-occupying lesion from RCC was highly suspected according to the clinical and radiological findings. INTERVENTIONS: The patient was advised to undergo further treatment, such as radiotherapy. OUTCOMES: The images of choroid metastasis were recorded by the smartphone with the interface eyepiece adapter mounted on the slit lamp handily. CONCLUSIONS: The smartphone with an interface eyepiece adapter mounted on the slit lamp can be widely used to record the precious images in the clinic in a timely manner.


Assuntos
Carcinoma de Células Renais/diagnóstico , Neoplasias da Coroide/diagnóstico , Plexo Corióideo/diagnóstico por imagem , Neoplasias Renais/patologia , Smartphone , Carcinoma de Células Renais/secundário , Neoplasias da Coroide/secundário , Feminino , Humanos , Neoplasias Renais/cirurgia , Pessoa de Meia-Idade , Nefrectomia , Lâmpada de Fenda , Microscopia com Lâmpada de Fenda/instrumentação , Tomografia Computadorizada por Raios X
4.
J Colloid Interface Sci ; 521: 1-10, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29544116

RESUMO

We report three types of conducting polymers (CPs), polyaniline (PANI), polypyrrole (PPY) and poly (3,4-ethylenedioxythiophene) (PEDOT) to modify the surface of the CdS nanorods to probe their photocorrosion inhibition and photocatalytic hydrogen production. Various characterizations, such as high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and density function theory (DFT) calculations have been conducted to reveal the intrinsic structure of the as-constructed CPs@CdS (@ means CPs at the surface of CdS) core-shell nanorods. The results show that the PANI and PPY shells with abundant N and C atoms can significantly enhance the binding energy of Cd and S atoms on the surface of the CdS nanorods. However, there is no obvious enhancement of binding energy at the interface of the PEDOT shell and the CdS nanorods core. Therefore, PANI@CdS and PPY@CdS possess stronger driving force than PEDOT@CdS to inject the photogenerated holes in conducting polymer shells. As a result, the polyaniline (PANI) modified PANI@CdS core-shell nanorods demonstrate the most effectively enhanced hydrogen production rate of ∼9.7 mmol h-1 g-1 and effective photocorrosion inhibition in 30 h without deactivation under visible-light irradiation. The hydrogen production performance of PPY@CdS is not effectively promoted owing to the weak transmittance of light for the PPY shell. The PEDOT shell cannot improve the hydrogen production and stability property of the CdS nanorods. This work could shed some light on conducting polymers modifying metal sulfides nanostructures that is of inconceivable significance for effective photocorrosion inhibition and highly enhanced photocatalytic activities.

5.
Small ; 11(17): 2003-10, 2015 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-25641812

RESUMO

An individual cyanobacterium cell is interfaced with a nanoporous biohybrid layer within a mesoporous silica layer. The bio-interface acts as an egg membrane for cell protection and growth of outer shell. The resulting bilayer shell provides efficient functions to create a single cell photosynthetic bioreactor with high stability, reusability, and activity.


Assuntos
Reatores Biológicos , Cianobactérias/metabolismo , Nanoconchas/química , Fotossíntese , Materiais Biocompatíveis/química , Biomassa , Dióxido de Carbono/química , Cisteína/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanotecnologia/métodos , Transição de Fase , Porosidade , Silício , Dióxido de Silício , Energia Solar , Propriedades de Superfície , Synechococcus , Raios Ultravioleta
6.
Eur J Radiol ; 84(3): 450-457, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25544555

RESUMO

PURPOSE: The study was performed to evaluate magnetic resonance (MR) issues for the latest standard brands of plates and screws used in orthopedic surgery at a 1.5-T MR system, including the safety and metallic artifacts. METHODS: The plates and screws (made of titanium alloy and stainless steel materials, according to the latest standard brands) were assessed for displacement in degrees, MRI-related heating and artifacts at a 1.5-T MR system. The displacement in degrees of the plates and screws was evaluated on an angel-measurement instrument at the entrance of the MR scanner. The MRI-related heating was assessed on a swine leg fixed with a plate by using a "worst-case" pulse sequence. A rectangular water phantom was designed to evaluate metallic artifacts of a screw on different sequences (T1/T2-weighted FSE, STIR, T2-FSE fat saturation, GRE, DWI) and then artifacts were evaluated on T2-weighted FSE sequence by modifying the scanning parameters including field of view (FOV), echo train length (ETL) and bandwidth to identify the influence of parameters on metallic artifacts. 15 volunteers with internal vertebral fixation (titanium alloy materials) were scanned with MR using axial and sagittal T2-FSE, sagittal T2-FSE fat suppression and STIR with conventional and optimized parameters, respectively. Then all images were graded by two experienced radiologists having the experience of more than 7 years under double-blind studies that is neither of them knew which was conventional parameter group and optimized parameter group. RESULTS: The average deflection angle of titanium alloy and stainless steel implants were 4.3° and 7.7°, respectively, (less than 45°) which indicated that the magnetically induced force was less than the weight of the object. The deflection angle of the titanium alloy implants was less than the stainless steel one (t=9.69, P<0.001). The average temperature changes of titanium alloy before and after the scan was 0.48°C and stainless steel implants was 0.74°C, respectively, with the background temperature changes of 0.24°C. The water phantom test indicated that the DWI sequence produced largest artifacts, while FSE pulse sequence produced smallest artifacts. And T2-weighted FSE fat saturation sequence produced larger artifacts than STIR sequence. The influence of the scanning parameters on metallic artifacts was verified that metallic artifacts increased with longer echo train length and bigger FOV, while decreased with larger bandwidth. The interreader agreement was good or excellent for each set of images graded with Cohen's Kappa statistic. Image grading of axial and sagittal T2-FSE with optimized parameters were significantly superior to that with conventional parameters (grade, 3.3±0.5 vs 2.7±0.6, P=0.003; 3.2±0.4 vs 1.9±0.7, P=0.001) and image of STIR sequence received a better grade than T2-FSE FS sequence (grade, 3.4±0.5 vs 1.7±0.6, P<0.001). CONCLUSIONS: The latest standard plates and screws used in orthopedic surgery do not pose an additional hazard or risk to patients undergoing MR imaging at 1.5-T or less. Though artifacts caused by them cannot be ignored because of their relatively large size, it is possible to be minimized by choosing appropriate pulse sequences and optimizing scanning parameters, such as FSE and STIR sequence with large bandwidth, small FOV and appropriate echo train length.


Assuntos
Imageamento por Ressonância Magnética , Próteses e Implantes , Idoso , Ligas , Androsterona/análogos & derivados , Artefatos , Parafusos Ósseos , Método Duplo-Cego , Segurança de Equipamentos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Metais , Pessoa de Meia-Idade , Imagens de Fantasmas , Titânio
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