[QMEC-based Analysis of the Soil Microbial Functional Potentials across Different Tibetan Plateau Glacier Forelands].

Soil microorganisms dominate the biogeochemical cycles of elements in glacier forelands, which continue to expand due to the climate warming. We analyzed the soil microbial functional characteristics among three types of glacier forelands on the Tibetan Plateau: Yulong Glacier (Y), a temperate glacier; Tianshan Urumqi Glacier No.1 (T), a sub-continental glacier; and Laohugou Glacier No.12 (L), a continental glacier. Here, soil microbial functional genes were quantified using quantitative microbial element cycling technology (QMEC). We found that, in the three glacier forelands, the abundances of soil microbial functional genes related to hemicellulose degradation and reductive acetyl-CoA pathway were highest compared with other carbon-related functional genes. The main nitrogen cycling genes were involved in ammonification. The functional genes of the phosphorus cycle and sulfur cycle were related to organic phosphate mineralization and sulfur oxidation. Furthermore, the soils of the temperate glacier foreland with better hydrothermal conditions had the most complex microbial functional gene structure and the highest functional potentials, followed by those of the soils of continental glacier foreland with the driest environment. These significant differences in soil microbial functional genes among the three types of glacier forelands verified the impacts of geographic difference on microbial functional characteristics, as well as providing a basis for the study of soil microbial functions and biogeochemical cycles in glacier forelands.

[Effect of Simulated Warming on Microbial Community in Glacier Forefield].

Glaciers are constantly retreating because of global warming. In this study, three soil samples along the forefield of Urumqi Glacier No. 1 were collected. The effects of warming on the microbial community in the glacier forefield were investigated through a 150-day laboratory experiment. In this experiment, two temperature treatments were performed at 5℃and 15℃. The results showed that with increasing deglaciation age, the concentrations of carbon and nitrogen increased and the abundance and alpha diversity of microbial communities increased in the original samples. The 150-day laboratory experiment indicated that warming insignificantly changed the copy number of archaea and bacteria. Furthermore, it changed the microbial community composition, and the changes varied in different sampling sites. Based on the analysis of abundant OTUs changing significantly with warming, the sampling sites with shorter deglaciation age had stronger response with warming, representing an increase in the abundance of genus Thiobacillus. Furthermore, these results revealed that warming caused different effects on microbes along glacier forefield and thus, it could provide important characteristics of the microbial community with warming in alpine glacier regions.

[Research on a novel high-precision methane concentration detection system].

In the gas concentration detection process using the characteristic spectrum absorption method, in order to improve the detection accuracy of the gas concentration, it often has to use the high-quality narrowband modulated laser and modulate wavelength to align with the characteristic absorption peaks of measured gas. But by this way, the cost of the laser and system requirements will be greatly increased. To use the existing portable, low-cost semiconductor laser conditions, at the same time it can obtain higher precision, conversion window differential absorption optical structure and the algorithm of differential characteristic absorption ratio was designed. Selection reason of position of the wavelength characteristic was analyzed, and steps to implement the processing algorithm were given. Systematically utilizing the combination method of conversion window and absorption gas chamber, by the method for calculating the ratio of the light intensity response, the light intensity from non-characteristic absorption peak position was divided out. So it achieved a similar detecting effect was achieved that used a narrow-band laser aligned to the feature absorption peak position. Experiments adopted MW-IR-1650 infrared laser, type SSM17-2 stepper motor control module, C30659 infrared detectors, and other devices. In the experiments, different concentrations of methane gas were tested, and experimental results show that the relative error of measurement was less than 2.0% within the range from 200 to 5000 ppm. In summary, it's proved that the system has high accuracy and stability.

[Research on detecting concentration of serum protein based on resonance Rayleigh scattering].

The resonance Rayleigh scattering spectral detection system was designed based on the 2, 9, 16, 23-tetracarboxylate-phthalocyanine zinc and protein system. In the system, excitation light source is 405 nm wide band gap semiconductor lasers, and monochromator is 475 nm narrow-band band-pass filter, and the detector is low-noise and high-gain photoelectric amplifier based on blue-ray enhanced photodiode. Experiment shows that, the solution's strong absorption wavelength is near 420 nm. Under the action of incentive light, resonance Rayleigh scattering is generated at the resonant wavelength, and the scattering intensity is proportional to the protein content. The system uses 2, 9, 16, 23-tetracarboxylate as the spectrum probe to determine the concentration of serum proteins by resonance Rayleigh scattering method. Its linear detection range is 10 - 50 mg.mL-1, and its detection limit is 0. 001 mg.mL-1. The newly developed device for detecting concentration of the serum protein has the advantages of small size, low cost, low power consumption, and being easy to use.

Application of the radial basis function interpolation to phase extraction from a single electronic speckle pattern interferometric fringe.

In this paper, we introduce the radial basis function (RBF) interpolation method to electronic speckle pattern interferometry (ESPI) and propose the RBF interpolation method to obtain unwrapped phase values based on a skeleton map. Because of the excellent approximation properties of the RBF interpolation, the proposed method can extract accurate phase values from a single fringe pattern effectively, even using a simple 3×3 mean filter as preprocessing. Using our method, both special filtering methods for ESPI fringes as preprocessing and postprocessing, including a dilatation and erosion algorithm for pruning and connecting and the smooth algorithm for improving the phase values are not needed. We test our method on a computer-simulated and two experimentally obtained poor-quality fringe patterns. The results have demonstrated that our RBF interpolation method works well even under a seriously disconnected skeleton map where it is impossible to apply the widely used, Matlab function grid data interpolation or the backpropagation neural networks method [Appl. Opt. 46, 7475 (2007)].

[Measurement technology for multi-parameter spectral responsivity of X-ray scintillation crystals].

Aimed at the measurement demand for development of better X-ray scintillation crystals, a photoelectrical detector for integrally test the multi-parameter spectral responsivity of scintillation crystals was developed. The conversion spectrum of the scintillation crystal excited by various X-ray energies under the critical focal length could be measured directly through the spectral output interface by one spectrometer, and the photovoltaic effect voltage of the PIN photodiode could be tested through the voltage output interface by one oscilloscope. Furthermore, the output power of fluorescence was calculated using an equivalent circuit. The measurement results show that the conversion efficiency of the scintillator declined along with the current increase of the X-ray tube while it has weak relation with the change in tube voltage. The experimental results show that the method presented in this paper is helpful for testing the scintillator properties.