Abstract： The homogeneous, intensity modulated salinity sensor using the photonic crystal ring resonator （PCRR） is proposed and designed for monitoring the salinity of the seawater from 0% to 100% （0 g/L to 100 g/...Abstract： The homogeneous, intensity modulated salinity sensor using the photonic crystal ring resonator （PCRR） is proposed and designed for monitoring the salinity of the seawater from 0% to 100% （0 g/L to 100 g/L） at 25℃. The concentration of the salinity in the seawater changes the refractive index of the seawater. The change in the refractive index of the seawater brings the change in the output signal intensity of the sensor as the output power and mapping the salinity level, the seawater flows inside the sensor. By detecting the salinity can be evaluated. The proposed sensor is composed of periodic Si rods embedded in an air host with a circular PCRR placed between the inline quasi waveguides. Approximately, 2.69% of output power reduction is observed for every 5% （5 g/L） increase in the salinity as the seawater has a unique refractive index for each salt level. With this underlying principle, the performance of the sensor is analyzed for different temperatures.展开更多
Based on Princeton Ocean model, circulation in the Yellow Sea and East China Sea and its annual cycle are simulated. The model results show a weak countercurrent on the left side of the Kuroshio. The countercurrent se...Based on Princeton Ocean model, circulation in the Yellow Sea and East China Sea and its annual cycle are simulated. The model results show a weak countercurrent on the left side of the Kuroshio. The countercurrent separates from the main stream of the Kuroshio around 30°N, 128°E, where the Kuroshio turns right to the Tokara Strait it flows southwestward along isobaths, meets with the offshore branch of Taiwan Warm Current around 28°N. 124°E, then returns back and joins the main stream, so that a cyclonic circulation is formed. The center and strength of the countercurrent and cyclonic circulation exhibits seasonal variation. The lower layer cold water observed on PN section of the East China Sea in summer and autumn is considered to be associated with the modeled cyclonic circulation. According to Rossby's wake-stream theory, lateral friction may be the main mechanism of the countercurrent on the left side of the Kuroshio.展开更多
Influence of temperature on measurement of surface plasmon resonance （SPR） sensor was investigated. Samples with various concentrations of NaCl were tested at different temperatures. It was shown that if the affecti...Influence of temperature on measurement of surface plasmon resonance （SPR） sensor was investigated. Samples with various concentrations of NaCl were tested at different temperatures. It was shown that if the affection of temperature could be neglected, measurement precision of salt solution was 0.028 wt.-%. But measurement error of salinity caused by temperature was 0.53 wt.-% in average when the temperature drift was 1 ℃. To reduce the error, a double-cell SPR sensor with salt solution and distilled water flowing respectively and at the same temperature was implemented.展开更多
A novel fiber Bragg grating (FBG) based chemical sensor using hydrogel, a swellable polymer, as sensitive element is demonstrated. The sensing mechanism relies on the shift of Bragg wavelength due to the stress result...A novel fiber Bragg grating (FBG) based chemical sensor using hydrogel, a swellable polymer, as sensitive element is demonstrated. The sensing mechanism relies on the shift of Bragg wavelength due to the stress resulted from volume change of sensitive swellable hydrogel responding to the change of external environment. A polyacrylamide hydrogel fiber grating chemical sensor is made, and the experiments on its sensitivity to the salinity are performed. The sensitivity is low due to the less stress from the shrinking or swelling of hdrogels. Reducing the cross diameter of the grating through etching with hydrofluoric acid can greatly improve the sensitivity of the sensor.展开更多
文摘Abstract： The homogeneous, intensity modulated salinity sensor using the photonic crystal ring resonator （PCRR） is proposed and designed for monitoring the salinity of the seawater from 0% to 100% （0 g/L to 100 g/L） at 25℃. The concentration of the salinity in the seawater changes the refractive index of the seawater. The change in the refractive index of the seawater brings the change in the output signal intensity of the sensor as the output power and mapping the salinity level, the seawater flows inside the sensor. By detecting the salinity can be evaluated. The proposed sensor is composed of periodic Si rods embedded in an air host with a circular PCRR placed between the inline quasi waveguides. Approximately, 2.69% of output power reduction is observed for every 5% （5 g/L） increase in the salinity as the seawater has a unique refractive index for each salt level. With this underlying principle, the performance of the sensor is analyzed for different temperatures.
文摘Based on Princeton Ocean model, circulation in the Yellow Sea and East China Sea and its annual cycle are simulated. The model results show a weak countercurrent on the left side of the Kuroshio. The countercurrent separates from the main stream of the Kuroshio around 30°N, 128°E, where the Kuroshio turns right to the Tokara Strait it flows southwestward along isobaths, meets with the offshore branch of Taiwan Warm Current around 28°N. 124°E, then returns back and joins the main stream, so that a cyclonic circulation is formed. The center and strength of the countercurrent and cyclonic circulation exhibits seasonal variation. The lower layer cold water observed on PN section of the East China Sea in summer and autumn is considered to be associated with the modeled cyclonic circulation. According to Rossby's wake-stream theory, lateral friction may be the main mechanism of the countercurrent on the left side of the Kuroshio.
基金This work was supported by the Shu Guang Project of Shanghai Education Committee (No. 02SG32)the Shanghai Leading Academic Discipline Project (No.T0501).
文摘Influence of temperature on measurement of surface plasmon resonance （SPR） sensor was investigated. Samples with various concentrations of NaCl were tested at different temperatures. It was shown that if the affection of temperature could be neglected, measurement precision of salt solution was 0.028 wt.-%. But measurement error of salinity caused by temperature was 0.53 wt.-% in average when the temperature drift was 1 ℃. To reduce the error, a double-cell SPR sensor with salt solution and distilled water flowing respectively and at the same temperature was implemented.
文摘A novel fiber Bragg grating (FBG) based chemical sensor using hydrogel, a swellable polymer, as sensitive element is demonstrated. The sensing mechanism relies on the shift of Bragg wavelength due to the stress resulted from volume change of sensitive swellable hydrogel responding to the change of external environment. A polyacrylamide hydrogel fiber grating chemical sensor is made, and the experiments on its sensitivity to the salinity are performed. The sensitivity is low due to the less stress from the shrinking or swelling of hdrogels. Reducing the cross diameter of the grating through etching with hydrofluoric acid can greatly improve the sensitivity of the sensor.
