Frequency responses of modulated electroluminescence(EL)of light-emitting diodes were measured using a testing setup.With increasing frequency of the ac signal,the relative light intensity(RLI)clearly decreases.Furthe...Frequency responses of modulated electroluminescence(EL)of light-emitting diodes were measured using a testing setup.With increasing frequency of the ac signal,the relative light intensity(RLI)clearly decreases.Furthermore,a peculiar asynchrony between the RLI and ac small-signal is observed.At frequencies higher than 10 kHz,the RLI clearly lags behind the ac signal and the absolute value of the lagging angle is nearly proportional to the signal frequency.Using the classical recombination model of light-emitting diodes under ac small-signal modulation,these abnormal characteristics of modulated EL can be clearly explained.展开更多
Hydrogen-free diamond-like carbon (DLC) films with the optical band gaps of 2.0-2.7 e V and the microhardness of 40-55 GPa are deposited by femtosecond KrF laser pulses. The film microstructure of nanometer spheroid i...Hydrogen-free diamond-like carbon (DLC) films with the optical band gaps of 2.0-2.7 e V and the microhardness of 40-55 GPa are deposited by femtosecond KrF laser pulses. The film microstructure of nanometer spheroid is observed. The filrn microhardness is improved with the increase of ion kinetic energy of plasma plume from 300 to 600 eV. The characteristics of DLC film deposition with fs pulses is discussed.展开更多
（Fe65 Co35 ）x （MgF2 ）1-x films with different metal volume fraction x are fabricated by magnetron sputtering. The results reveal that good soft magnetic properties can be obtained in a very wide x range （0.9 〉 x...（Fe65 Co35 ）x （MgF2 ）1-x films with different metal volume fraction x are fabricated by magnetron sputtering. The results reveal that good soft magnetic properties can be obtained in a very wide x range （0.9 〉 x 〉 0.55） with Hc not exceeding 10 Oe, and high resistivity is also realized for the samples. Especially for the sample with x = 0.75, the coercivity in hard and easy axes is 1.6 Oe and 8.5 Oe, respectively, 4πMs = 14.1 kG and p reaches 1.16 mΩ2.cm. The dependence of complex permeability μ =μ′ - jμ″ on frequency shows that the real part μ′is more than 190 below 2.0 GHz and ferromagnetic resonance frequency fr reaches 2.43 GHz, implying that the film is promising for high frequency applications. High resolution transmission electron micrographs show that the films consists of bcc Fe65 Co35 particles embedded uniformly in an amorphous insulating MgF2 matrix with particle size around a few nanometers. The excellent soft magnetic properties and high frequency properties are ascribed to exchange of coupling among magnetic granules, and the exchange coupling variation in a wide x range （0.9 〉 x 〉 0.55） is studied systematically by △M plots.展开更多
Background Gastric cancer （GC） is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fat...Background Gastric cancer （GC） is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fatty acid and fatty acid amide metabolic perturbations associated with GC morbidity.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos.60876035,50901050,11004148 and 11004149.
文摘Frequency responses of modulated electroluminescence(EL)of light-emitting diodes were measured using a testing setup.With increasing frequency of the ac signal,the relative light intensity(RLI)clearly decreases.Furthermore,a peculiar asynchrony between the RLI and ac small-signal is observed.At frequencies higher than 10 kHz,the RLI clearly lags behind the ac signal and the absolute value of the lagging angle is nearly proportional to the signal frequency.Using the classical recombination model of light-emitting diodes under ac small-signal modulation,these abnormal characteristics of modulated EL can be clearly explained.
基金Supported by the National Natural Science Foundation of China under Grant No.19835030.
文摘Hydrogen-free diamond-like carbon (DLC) films with the optical band gaps of 2.0-2.7 e V and the microhardness of 40-55 GPa are deposited by femtosecond KrF laser pulses. The film microstructure of nanometer spheroid is observed. The filrn microhardness is improved with the increase of ion kinetic energy of plasma plume from 300 to 600 eV. The characteristics of DLC film deposition with fs pulses is discussed.
基金Supported by the National Natural Science Foundation of China under Grant No 50901050.
文摘（Fe65 Co35 ）x （MgF2 ）1-x films with different metal volume fraction x are fabricated by magnetron sputtering. The results reveal that good soft magnetic properties can be obtained in a very wide x range （0.9 〉 x 〉 0.55） with Hc not exceeding 10 Oe, and high resistivity is also realized for the samples. Especially for the sample with x = 0.75, the coercivity in hard and easy axes is 1.6 Oe and 8.5 Oe, respectively, 4πMs = 14.1 kG and p reaches 1.16 mΩ2.cm. The dependence of complex permeability μ =μ′ - jμ″ on frequency shows that the real part μ′is more than 190 below 2.0 GHz and ferromagnetic resonance frequency fr reaches 2.43 GHz, implying that the film is promising for high frequency applications. High resolution transmission electron micrographs show that the films consists of bcc Fe65 Co35 particles embedded uniformly in an amorphous insulating MgF2 matrix with particle size around a few nanometers. The excellent soft magnetic properties and high frequency properties are ascribed to exchange of coupling among magnetic granules, and the exchange coupling variation in a wide x range （0.9 〉 x 〉 0.55） is studied systematically by △M plots.
文摘Background Gastric cancer （GC） is one of the most common types of cancer in the world. A change in the metabolism of lipids in tumor cells could lead to the pathogenesis of cancer. In this study, we investigated fatty acid and fatty acid amide metabolic perturbations associated with GC morbidity.
