We introduce a novel method to accurately extract the optical parameters in terahertz reflection imaging. Our method builds on standard self-referencing methods using the reflected signal from the bottom of the imagin...We introduce a novel method to accurately extract the optical parameters in terahertz reflection imaging. Our method builds on standard self-referencing methods using the reflected signal from the bottom of the imaging window material to further compensate for time-dependent system fluctuations and position-dependent variation in the window thickness. Our proposed method not only improves the accuracy, but also simplifies the imaging procedure and reduces measurement times.展开更多
In this paper, we proposed a novel resolution criterion(improved calibrated normalized resolution product, r*') to evaluate separation quality of fingerprints. By comparing with the calibrated normalized resolutio...In this paper, we proposed a novel resolution criterion(improved calibrated normalized resolution product, r*') to evaluate separation quality of fingerprints. By comparing with the calibrated normalized resolution product(r*) and the hierarchical chromatographic response function(HCRF), the validity of this criterion was demonstrated by experimental chromatograms. The soy isoflavone extract was selected as the analytical object. The initial and end percentages of methanol and elution time affecting gradient elution were tested by orthogonal design. The final optimized conditions were as follows. It was detected by UV absorbance at 254 nm, column temperature was maintained at 36 oC, solvent A was 0.1%(v/v) acetic acid, solvent B was methanol, gradient elution was from 34% to 65% B in a linear gradient in 25 min, and the flow-rate was set at 1.0 m L/min. In addition, the main ingredients of the soy isoflavone extract were confirmed by LC-ESI/MS.展开更多
基金Research Grants Council of Hong Kong(415313,14205514)Direct Grant,Chinese University of Hong Kong
文摘We introduce a novel method to accurately extract the optical parameters in terahertz reflection imaging. Our method builds on standard self-referencing methods using the reflected signal from the bottom of the imaging window material to further compensate for time-dependent system fluctuations and position-dependent variation in the window thickness. Our proposed method not only improves the accuracy, but also simplifies the imaging procedure and reduces measurement times.
基金National Higher-Education Institution General Research and Development Funding(Grant No.JKP2011010)
文摘In this paper, we proposed a novel resolution criterion(improved calibrated normalized resolution product, r*') to evaluate separation quality of fingerprints. By comparing with the calibrated normalized resolution product(r*) and the hierarchical chromatographic response function(HCRF), the validity of this criterion was demonstrated by experimental chromatograms. The soy isoflavone extract was selected as the analytical object. The initial and end percentages of methanol and elution time affecting gradient elution were tested by orthogonal design. The final optimized conditions were as follows. It was detected by UV absorbance at 254 nm, column temperature was maintained at 36 oC, solvent A was 0.1%(v/v) acetic acid, solvent B was methanol, gradient elution was from 34% to 65% B in a linear gradient in 25 min, and the flow-rate was set at 1.0 m L/min. In addition, the main ingredients of the soy isoflavone extract were confirmed by LC-ESI/MS.