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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(7): 1864-9, 2015 Jul.
Article in Chinese | MEDLINE | ID: mdl-26717741

ABSTRACT

Forest bio-fuel, a new type renewable energy, has attracted increasing attention as a promising alternative. In this study, a new method called Sparse Partial Least Squares Regression (SPLS) is used to construct the proximate analysis model to analyze the fuel characteristics of sawdust combining Near Infrared Spectrum Technique. Moisture, Ash, Volatile and Fixed Carbon percentage of 80 samples have been measured by traditional proximate analysis. Spectroscopic data were collected by Nicolet NIR spectrometer. After being filtered by wavelet transform, all of the samples are divided into training set and validation set according to sample category and producing area. SPLS, Principle Component Regression (PCR), Partial Least Squares Regression (PLS) and Least Absolute Shrinkage and Selection Operator (LASSO) are presented to construct prediction model. The result advocated that SPLS can select grouped wavelengths and improve the prediction performance. The absorption peaks of the Moisture is covered in the selected wavelengths, well other compositions have not been confirmed yet. In a word, SPLS can reduce the dimensionality of complex data sets and interpret the relationship between spectroscopic data and composition concentration, which will play an increasingly important role in the field of NIR application.


Subject(s)
Biofuels/analysis , Biomass , Wood/chemistry , Least-Squares Analysis , Models, Theoretical , Spectroscopy, Near-Infrared
2.
Mol Med Rep ; 8(1): 233-7, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23653117

ABSTRACT

The aim of this study was to evaluate the efficacy of autologous platelet-rich plasma (PRP) combined with erbium fractional laser therapy for facial acne or acne scars. PRP combined with erbium fractional laser therapy was used for the treatment of 22 patients, including 16 patients who suffered from facial acne scars and 6 patients who suffered from acne scars concomitant with acne. Whole blood (40 ml) was collected from each patient, and following differential centrifugation, PRP was harvested. After using an erbium fractional laser, we applied PRP to the entire face of every patient. Digital photos were taken before and after the treatment for evaluation by dermatologists and the patients rated the efficacy on a 5-point scale. The erythema was moderate or mild, while its total duration was <3 days; after receiving the treatment three times, 90.9% of the patients showed an improvement of >50%, and 91% of the patients were satisfied; no acne inflammation was observed after treatment. PRP combined with erbium fractional laser therapy is an effective and safe approach for treating acne scars or acne, with minimal side-effects, and it simultaneously enhanced the recovery of laser-damaged skin.


Subject(s)
Acne Vulgaris/therapy , Cicatrix/therapy , Low-Level Light Therapy , Platelet-Rich Plasma , Adult , Erbium , Female , Humans , Male , Treatment Outcome , Young Adult
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(4): 721-5, 2008 Apr.
Article in Chinese | MEDLINE | ID: mdl-18619283

ABSTRACT

In order to deeply understand the spectral characteristics of beta-D-galactopyranose in the terahertz region, terahertz time-domain spectroscopy was used to measure the absorption coefficient and refractive index in the frequency range 0.3-3.0 THz at room temperature, and Fourier transform infrared spectroscopy was also used to obtain the absorption spectrum between 1.5 and 19.5 THz. In parallel with the experimental study, the 6-311+G * * basis set and density functional theory(DFT) were applied to obtain the structure and vibrational frequencies of the isolated beta-D-galactopyranose molecule at in phase. The observed vibrational spectra were assigned according to the DFT calculations. Results show that the theoretical calculations are in good agreement with the experimental data except somewhat blue shifts due to the intermolecular interactions. The observed resonances at the high frequency above 6 THz originate from distinct intra-molecular vibrational modes, while at the low frequency below 6 THz the observed resonances are dominated by vibrations of hydrogen bonds between the molecules or phonon modes. The comparison of experimental and theoretical studies shows that far-infrared absorption features are highly sensitive to the structure and spatial arrangement of molecules.


Subject(s)
Galactose/analysis , Terahertz Spectroscopy/methods , Crystallization , Hydrogen Bonding , Models, Molecular , Molecular Conformation , Spectrophotometry, Infrared , Terahertz Spectroscopy/instrumentation , Vibration
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