[Non-Invasive Detection of Blood Glucose Concentration Based on Photoacoustic Spectroscopy Combined with Principle Component Regression Method].

This paper presents a photoacoustic noninvasive setup of detecting blood glucose based on the tunable pulsed laser coupled with the confocal ultrasonic transducer and the forward detection model. To validate the reliability of the setup, in the experiments, the different concentrations of glucose aqueous solution are excitated by the Q-switched 532 nm pumped Nd∶YAG pulsed laser to generate the time-resolved photoacoustic signals. And the glucose aqueous solutions are scanned by the tunable pulsed laser in the infrared waveband from 1 300 to 2 300 nm with the interval of 10nm and the photoacoustic peak-to-peak values are gotten. The difference spectral method is used to get the characteristic wavelengths of glucose, and the principle component regression algorithm is used to determine three optimal wavelengths and establish the correction mathematical model between the photoacoustic peak-to-peak values and the concentrations. The experimental results demonstrate that the mechanism of the photoacoustic signal is agreement with the cylindrical model, and the predicted results of the correction and prediction samples based on the established correction model demonstrate that the root-mean-square error of correction and prediction are all less than 10 mg·dl-1, the correlation coefficient reaches 0.993 6.

Raman Spectra of Bredigite at High Temperature and High Pressure.

Bredigite was synthesized by using the Piston-Cylinder in 1.2 GPa and 1 473 K. With external heating device and diamond anvil cell, high temperature and high pressure Raman spectra of bredigite were collected at temperatures 298, 353, 463, 543, 663, 773 and 873 K and with pressure from 1 atm up to 14.36 GPa (room temperature). The SEM image showed that the sample consisted of one crystalline phase with grain size ranging from 10～20 µm. The EPMA data suggest a chemical formula of Ca7.03(2)Mg0.98(2)Si3.94(2)O16 which was identical to the theoretical component of bredigite. The Raman spectroscopic results indicate there were 29 vibration bands of bredigite at high temperature. Some bands were merging, weakening and disappearing increasingly with the temperature, which was obvious in the range of 800~1 200 cm-1. The vibration bands of 909, 927 and 950 cm-1 disappeared at 873, 773 and 873 K, respectively. The results primarily indicated that the structure of bredigite was stable under experimental condition. In addition, isobaric mode-Grüneisen parameters and isothermal mode-Grüneisen parameters were calculated, yielding 1.47(2) and 0.45(3) as their mean values, respectively. Anharmonic coefficients were estimated based on the high temperature and high pressure Raman experiments, showing that the contributions to anharmonic-effect induced with the Si­O vibration modes were smaller than other modes.

Simultaneous UPLC analysis of three major flavonoids in granule decoctions of Fructus aurantii-type formulae.

A simple, rapid, and sensitive liquid chromatographic method has been established for the simultaneous analysis of three compounds (narirutin, hesperidin and naringin), in granule decoctions of Fructus Aurantii-type formulae. The compounds were separated in less than 10 min using a C18 column with gradient elution using (A) acetonitrile, (B) water, and (C) acetic acid at a flow rate of 0.3 mL/min, and with a PDA detector. The method was validated for specificity, accuracy, precision, and limits of detection. Good linear regression data (r2 > 0.9980) were obtained for all the calibration plots within the ranges tested. The method is an attractive alternative for quality control and clinical monitor of granule decoctions of Fructus Aurantii-type formulae.

[Study on infrared spectra characteristics of fault particles of the sulfide deposit].

Predecessors researched emphatically the mineralization and the movement of ore body in space in fault movement. Study on particles that were formed from sulfide ore and wall rock in fault movement has been always ignored. The present paper studies the fault particles of the sulfide deposit using the FTIR spectroscopic spectra and scanning electron microscope. The results show that the samples consist of hydrous calcium sulphate, hydrous sulfur calcium carbonate, quartz, sericite, and organic matter. This shows that S(2-) in sulfide minerals is oxidized and transformed into S(6+) in fault movement. Sulfide minerals formed hydrous calcium sulphate and sulfide minerals and carbonate minerals formed hydrous sulfur calcium carbonate. Hydrous sulfur calcium carbonate is a mineral newly discovered in our study. The research results not only can be applied in the prospect and the exploration of this ore deposit type but also is important for ore utilization. In addition, this paper discussed identification characteristics of infrared spectrum of hydrous calcium sulphate and hydrous sulfur calcium carbonate and pointed out that infrared spectral analysis is suitable for analysis of hydrous calcium sulphate and hydrous sulfur calcium carbonate particles formed in fault movement.

On-line estimation of concentration parameters in fermentation processes.

It has long been thought that bioprocess, with their inherent measurement difficulties and complex dynamics, posed almost insurmountable problems to engineers. A novel software sensor is proposed to make more effective use of those measurements that are already available, which enable improvement in fermentation process control. The proposed method is based on mixtures of Gaussian processes (GP) with expectation maximization (EM) algorithm employed for parameter estimation of mixture of models. The mixture model can alleviate computational complexity of GP and also accord with changes of operating condition in fermentation processes, i.e., it would certainly be able to examine what types of process-knowledge would be most relevant for local models' specific operating points of the process and then combine them into a global one. Demonstrated by on-line estimate of yeast concentration in fermentation industry as an example, it is shown that soft sensor based state estimation is a powerful technique for both enhancing automatic control performance of biological systems and implementing on-line monitoring and optimization.