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Complex ZnO compound material has great potential applications for optoelectronic devices. In this article, we give report to a simulation growth of a kind of special“fruiting ball”——natural “Platanus Occidentalis” made of Al2O3, Au and ZnO. The surface of “Platanus Occidentalis ” has numerous tiny Au seeds on the surface of Al2O3 ball. ZnO needles synthesized by the electrodeposition technique grow well on the Au seed layer. The obtained mono dispersive needles (or hexagonal columns) have different distribution density. The prepared sample looks like the assembled “Platanus Occidentalis” in photographs of scanning electron microscopy (SEM). Photoluminescence (PL) of samples at 6 K temperature and other characteristics are investigated. The appearance of sharp bound exciton (BE) emission line and the longitudinal optical (LO)-phonon replicas imply that the ZnO nanocolumns are of high optical quality.

Terahertz frequency resolution is an important factor affecting substance identification, but the presence of the device reflection within the terahertz time domain spectroscopy systems, causes the presence of a plurality of reflection peaks in the reference and measurement signals with low frequency resolution, because of the length truncation of time domain signal. In order to remove the influence of the reflection peak, this paper proposes a method based on empirical mode decomposition to remove the time domain reflection peak, to improve the terahertz frequency resolution. The time domain reflection peaks are positioned by correlation with the real terahertz peak, calculating the reflection peak upper and lower envelope and an average, obtaining intrinsic mode functions, and alternating reflection peaks with intrinsic mode functions, the effective length of the time domain signal is increased to improve the terahertz frequency resolution. Water vapor in the air terahertz transmission spectroscopy results show that this method can self adaptively remove a plurality of reflection peaks and has good repairing effect on the terahertz time-domain signal; the frequency resolution is increased by 12 times; and the useful information of absorption spectrum is not lost; the absorption peak position and the number is consistent with real spectrum; the terahertz spectrum ability to identify is well preserved.

The present paper brings the parameters of the detection fiber into Monte Carlo model, and we studied the influence of fiber optic parameters and the distance of fiber from the detector on the detected optic signal,. The simulation results show that signals are obviously different when the NA (numerical aperture) and diameter of the fiber are different respectively. With the increase in NA and diameter of the fiber, the diffuse reflectance and diffuse transmission increase gradually. However, the distance from the sample surface, to some extent, brings little influence when we control it within 1 mm. By further study of the simulation result, we found that the collection efficient of the fiber is the same in different spatial positions. And the collection efficient of strong scattering material is a constant, in spite of absorption coefficient and scattering coefficient. We can normalize the diffuse signals collected by fibers with different angular aperture beta by the collection efficient. Meanwhile, this paper provided the fitting curve of the collection efficient in a certain range. For fibers with different diameters, we can get a good consistence by area normalization. Therefore, the research on the effects of the difference of the detection fiber on diffuse hyper-spectrum has great significance for practical measurement. And the detection results can be transplanted by collection efficient and area normalization when we change the actual detecting fiber.

The technology of tongue near-infrared reflectance spectra was used for human serum total protein (TP) content of noninvasive testing for the first time. Reflectance spectrum on the tongue tips of 58 volunteers was collected, and the biochemical values of serum total protein were recorded at the same time. The samples were separated into two parts: training set and prediction set. Two prediction models were established using PCA combined with BP neural network and PLS. Using PCA-BP model to predict the prediction set, the average relative error is 7.35%, RMSEP was 6.3771 g x L(-1), and the correlation coefficient was 0.9021. Using PLS model to predict the prediction set, the average relative error is 4.77%, RMSEP was 0.1304 g x L(-1), and the correlation coefficient was 0.9718. It was approved that reflectance spectra of tongue can be used to predict TP accurately and noninvasively.

The present paper used synthesized data from the experiment samples to replace partial basic experiments, and increased the training samples amount from 14 to 27. In principal component analysis (PCA), the dimensionality of multivariate data was reduced to n principal components and almost all data information was kept. The PCA reduced the network's input nodes from 60 to 3 to simplify the neural network's structure. Finally, back-propagation neural network was used to train and predict these samples. It had 27 training samples, the input layer had three nodes, the hidden layer had two nodes, and the output layer had two nodes. Its excitation function is variable learning rate method. The results show that the coefficient of recovery can reach 89.6-109.0. It has reached the expected purpose.

The development of near-infrared-based techniques for the noninvasive determination of blood component concentrations has attracted significant interest in recent years. But the noninvasive measurement of blood compositions has not yet been applied to the clinical field except blood oxygen saturation. The most important and also difficult problems are the effects of individual discrepancy and complicated measurement conditions. In the present article, the approach of dynamic spectrum (DS) is introduced, which is based on the principle of photoplethysmography. It is very difficult too to pick up DS with high precision in time domain. In order to extract the DS with high accuracy, the FFT method and it's leakage are discussed. The influences of sampling speed, sampling signal periodicity, window function and unsynchronized sample are analyzed by emulating experiments. The result of emulating experiments shows that choosing certain sampling speed, sampling signal periodicity, window function and interpolation arithmetic will improve accuracy observably. This provides necessary condition for the clinical application of DS.

The pulse oximeter used to measure patients oxygen saturation non-invasively and continuously, has numerous applications in clinic care. The pulse oximetry measurement combines two basic methods, spectrophotometry and photoplethysmography (PPG). The red light and the infrared light are exposed to the ear lobe, finger or other tissue with fluctuation of artery blood, and then detected. The amplitude ratio of the photoplethysmography waveform of red light and infrared light varies with the oxygen saturation of blood. The measuring principle of the pulse oximeter is based on traditional test method, its accuracy is not gratifying due to various factors influencing the measurement result, such as the principle, measuring condition, and individual discrepancy. In the present paper a new pulse oximetry based on dynamic spectroscopy is introduced, It can promote the accuracy of the pulse oximeter evidently. The dynamic spectroscopy method is able to eliminate the interference of individual discrepancy and measuring condition in principle. This new method can eliminate the measurement error of pulse oximetry theoretically.

For non-invasive blood components detection using near-infrared spectrum, eliminating the influence of the individual difference is very important. In the non-invasive component measurement, the individual discrepancy refers to the difference of personal feature in measured tissues except the pulsatile component of artery blood, including hairs, horny layer, subcutaneous tissue, muscle, skeleton etc. It is declared that the individual discrepancy is different from the personal feature; it is an important factor blocking the practice of the technology. In the present article, a new method of detecting blood components is presented, which is based on the principle of photoplethysmography and Fourier transform. With this method, the influence of individual difference caused by skin and other tissues can be mostly eliminated, and the absorbance of artery blood could be obtained. The concept of the frequency domain extracting method was presented. The experiment was done and the dynamic spectrum which only evaluates the pulsatile part of the entire optical signal was obtained. The advantage of dynamic spectrum with frequency domain extracting method is analyzed. The result shows that the method can be realized and has many advantages.

Based on the chemiluminescence reaction of KMnO4-HNO3-2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside sensitized by HCHO, an analytical method for 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside by RP-HPLC with chemiluminescence detector was developed. The chromatographic conditions were optimized. AN ODS hypersil column(25 mm x 4.0 mm, 125 x 4.0 mm i.d. 5 microm) was used with acetonitrile--0.3% H3PO4 [25:75, (phi)] as mobile phase, and the flow rate was 0.8 mL x min(-1) at the column temperature of 40 degrees C. The linear range of calibration curve was from 15.75 to 136.5 microg x mL(-1), the detection limit was 11.83 microg x mL(-1) with a concentration of 21 microg x mL(-1) of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside, and the recovery was 102%-108%. The relative standard deviation was 3.45% (Cs = 21.0 microg x mL(-1), n = 3). The method has been applied to the determination of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside in a few Chinese medicines, and the results were satisfactory. The method was simple, rapid and highly selective.