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1.
Front Neurosci ; 17: 1131247, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816121

RESUMO

Purpose: Glaucoma is the main blindness-causing disease in the world. Previous neuroimaging studies demonstrated that glaucoma not only causes the loss of optic ganglion cells but also leads to the abnormal function of the optic nerve pathway and the visual cortex. However, previous studies also reported that patients with glaucoma have dysfunction in the visual cortex in a static state. Whether or not patients with primary angle-closure glaucoma (PACG) were accompanied by dynamic functional connectivity (FC) changes in the primary visual cortex (V1) remains unknown. Methods: A total of 34 patients with PACG (23 men and 11 women) and 34 well-matched healthy controls (HCs) were enrolled in the study. The dynamic functional connectivity (dFC) with the sliding window method was applied to investigate the dynamic functional connectivity changes in the V1. Results: Compared with HCs, patients with PACG showed increased dFC values between left V1 and bilateral calcarine (CAL). Meanwhile, patients with PACG showed increased dFC values between right V1 and bilateral CAL. Conclusion: Our study demonstrated that patients with PACG showed increased dFC within the visual network, which might indicate the increased variability FC in the V1 in patients with PACG.

2.
ACS Appl Mater Interfaces ; 6(4): 2255-61, 2014 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-24490685

RESUMO

High dielectric constant (high-k) Al2O3 thin films were prepared on ITO glasses by reactive RF-magnetron sputtering at room temperature. The effect of substrate bias on the subband structural, morphological, electrode/Al2O3 interfacial and electrical properties of the Al2O3 films is systematically investigated. An optical method based on spectroscopic ellipsometry measurement and modeling is adopted to probe the subband electronic structure, which facilitates us to vividly understand the band-tail and deep-level (4.8-5.0 eV above the valence band maximum) trap states. Well-selected substrate biases can suppress both the trap states due to promoted migration of sputtered particles, which optimizes the leakage current density, breakdown strength, and quadratic voltage coefficient of capacitance. Moreover, high porosity in the unbiased Al2O3 film is considered to induce the absorption of atmospheric moisture and the consequent occurrence of electrolysis reactions at electrode/Al2O3 interface, as a result ruining the electrical properties.

3.
Huan Jing Ke Xue ; 33(8): 2766-72, 2012 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-23213903

RESUMO

For improving the performance and sludge settling property of an activated sludge reduction process with uncoupler, in this investigation, uncoupler and nano-sized magnetic particles were added simultaneously to a sequencing batch reactor for exploring their synergistic effects to the characteristics of activated sludge. The results showed that the volume reduction of sludge reached 41% with single 2,4,5-Trichlorophenol (TCP) Comparing with the control experiment, the biodegradability and settling properties of the activated sludge decreased. Under the actions of TCP combined with nano-sized magnetic particles, the volume reduction of sludge reached 34%, the removal efficiencies of COD, nitrogen, and phosphorus as well as the sludge settling property were not significantly influenced. After 31 d's operation, the dehydrogenase activity was improved by 10%-18% and exhibited an accumulative effect over time. It was observed with an optical microscope that the species and amounts of protozoon and metazoan increased and a compact structure of sludge floc was formed. The results also indicated that using nano-sized magnetic particles and uncoupler could restrict the yield of excess sludge and improve the performance of an activated sludge system.


Assuntos
Nanopartículas de Magnetita/química , Esgotos/química , Desacopladores/química , Eliminação de Resíduos Líquidos/métodos , Clorofenóis/química , Cidades , Nitrogênio/isolamento & purificação , Fósforo/isolamento & purificação , Esgotos/análise , Águas Residuárias/química
4.
ACS Appl Mater Interfaces ; 4(10): 5673-7, 2012 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-23025234

RESUMO

In this paper, SnO(x) films were produced by reactive radio frequency magnetron sputtering under various oxygen partial pressure (P(O)) in conjunction with a thermal annealing at 200 °C afterwards. The obtained SnO(x) films were systematically studied by means of various techniques, including X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, spectroscopic ellipsometry, and Hall-effect measurement. The structural, chemical, and electrical evolution of the SnO(x) films was found to experience three stages: polycrystalline SnO phase dominated section with p-type conduction at P(O) ≤ 9.9%; amorphous SnO(2) phase dominated area at P(O) ≥ 12.3%, exhibiting n-type characteristics; and conductivity dilemma area in between the above mentioned sections, featuring the coexistence of SnO and SnO(2) phases with compatible and opposite contribution to the conductivity. The polycrystalline to amorphous film structure transition was ascribed to the enhanced crystallization temperature due to the perturbed structural disorder by incorporating Sn(4+) into the SnO matrix. The inversion from p-type to n-type conduction with P(O) variation is believed to result from the competition between the donor and acceptor generation process, i.e., the n-type behavior would be present if the donor effect is overwhelming, and vice versa. In addition, with increasing P(O), the refractive index decreased from 3.0 to 1.8 and the band gaps increased from 1.5 to 3.5 eV, respectively.

5.
ACS Appl Mater Interfaces ; 2(6): 1565-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20496870

RESUMO

In this letter, it is proposed that the usage of Al(2)O(3) capping layer can tremendously improve the phase stability of SnO thin films, which allows the accurate determination of the optical constants of the SnO films without the perturbation arising from impurity phases. For the SnO films, the refraction index and extinction coefficient are significantly influenced by the crystallinity. The nondirect optical bandgap of the amorphous SnO films is determined to be 2.27 eV, whereas two nondirect optical transitions are observed in the polycrystalline SnO films and the corresponding gap energies are estimated to be 0.50 and 2.45 eV, respectively.

6.
ACS Appl Mater Interfaces ; 2(4): 1060-5, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20423126

RESUMO

A simple, cost-effective, two-step method was proposed for preparing single-phase SnO polycrystalline thin films on quartz. X-ray diffraction (XRD) analysis demonstrated that the annealed films were consisted of polycrystalline alpha-SnO phase without preferred orientation, and chemical composition analysis of the single phase in nature was analyzed using X-ray photoelectron spectroscopy (XPS). Transmittance spectra in UV-vis-IR range indicated that the average transmittance of both the as-deposited and the annealed SnO thin films was up to 70%. The optical band gap decreased from 3.20 to 2.77 eV after the annealing process, which was attributed to the crystalline size related quantum size effect. Photoluminescence (PL) spectrum of the annealed film showed only a weak peak at 585 nm, and no intrinsic optical transition emission was observed. Moreover, the p-type conductivity of SnO film was confirmed through Hall effect measurement, with Hall mobility of 1.4 cm(2) V(-1) s(-1) and hole concentration of 2.8 x 10(16) cm(-3).

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