Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Base de dados
Tipo de estudo
Tipo de documento
Intervalo de ano de publicação
1.
Sci Rep ; 11(1): 1093, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441851

RESUMO

Unlike the single grating Czerny-Turner configuration spectrometers, a super-high spectral resolution optical spectrometer with zero coma aberration is first experimentally demonstrated by using a compound integrated diffraction grating module consisting of 44 high dispersion sub-gratings and a two-dimensional backside-illuminated charge-coupled device array photodetector. The demonstrated super-high resolution spectrometer gives 0.005 nm (5 pm) spectral resolution in ultra-violet range and 0.01 nm spectral resolution in the visible range, as well as a uniform efficiency of diffraction in a broad 200 nm to 1000 nm wavelength region. Our new zero-off-axis spectrometer configuration has the unique merit that enables it to be used for a wide range of spectral sensing and measurement applications.

2.
Sci Rep ; 9(1): 10211, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308474

RESUMO

Optical spectrometers play a key role in acquiring rich photonic information in both scientific research and a wide variety of applications. In this work, we present a new spectrometer with an ultrahigh resolution of better than 0.012 nm/pixel in the 170-600 nm spectral region using a grating-integrated module that consists of 19 subgratings without any moving parts. By using two-dimensional (2D) backsideilluminated complementary metal-oxide-semiconductor (BSI-CMOS) array detector technology with 2048 × 2048 pixels, a high data acquisition speed of approximately 25 spectra per second is achieved. The physical photon-sensing size of the detector along the one-dimensional wavelength direction is enhanced by a factor of 19 to approximately 428 mm, or 38912 pixels, to satisfy the requirement of seamless connection between two neighboring subspectral regions without any missing wavelengths throughout the entire spectral region. As tested with a mercury lamp, the system has advanced performance capabilities characterized by the highest k parameter reported to date, being approximately 3.58 × 104, where k = (working wavelength region)/(pixel resolution). Data calibration and analysis as well as a method of reducing background noise more efficiently are also discussed. The results presented in this work will stimulate further research on precision spectrometers based on advanced BSI-CMOS array detectors in the future.

3.
Zhonghua Zhong Liu Za Zhi ; 30(9): 706-8, 2008 Sep.
Artigo em Zh | MEDLINE | ID: mdl-19173917

RESUMO

OBJECTIVE: To investigate the efficacy, indication and complication of radiofrequency ablation (RFA) with cool-tip needle in patients with hepatic malignancies. METHODS: 421 patients with hepatic malignancies underwent ultrasound-guided RFA with cool-tip needle under local anaesthesia. The tumor size was from 1.0 to 15 cm in diameter with an average diameter of 4.3 cm. RESULTS: The complete ablation (CA) rate was 91.4% (382/418) in the patients with a tumor < 3 cm, 78.9% (97/123) in those with a tumor of 3 to 5 cm and 37.6% (35/93) in the patients with a tumor > 5 cm. No patient died or changed to celiotomy during the 1121 times of RFA for 634 lesions in 421 patients. No hemorrhage occurred in any of these patients after the RFA treatment. The complications included abdominal pain in 32.3% (136/421), nausea in 9.0% (38/421), fever in 34.9% (147/421) and biliary leakage in 0.2% (1/421) of the patients. CONCLUSION: Ultrasound-guided percutaneous radiofrequency ablation with cool-tip needle is effective and safe in the treatment of liver tumors.


Assuntos
Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Dor Abdominal/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/secundário , Ablação por Cateter/efeitos adversos , Feminino , Febre/etiologia , Neoplasias Gastrointestinais/secundário , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Ultrassonografia de Intervenção
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA