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New quaternary tellurides, Cs(2)Ge(3)M(6)Te(14) (M = Ga, In), were discovered by solid-state reactions. These compounds crystallize in space group P3ml (No. 164), with a = b = 8.2475(2) Å, c = 14.2734(8) Å, and V = 840.82(6) Å(3) (Z = 1) for Cs(2)Ge(3)Ga(6)Te(14) (1) and a = b = 8.5404(2) Å, c = 14.6766(8) Å, and V = 927.07(6) Å(3) (Z = 1) for Cs(2)Ge(3)In(6)Te(14) (2). The remarkable structural feature is the novel three-dimensional [Ge(3)M(6)Te(14)](2-) anionic framework made by condensed In(6)Te(14) (or Ga(6)Te(14)) layers that are connected alternately by dimeric Ge(3+)(2)Te(6) units and Ge(2+)Te(6) octahedra along the c direction. The presence of Ge centers with different oxidation states is also supported by the results of the electron localization function calculation and X-ray photoelectron spectroscopy measurement.

The effect of arc plasma ionization on its temperature diagnosis by the measurement of the refractive index is discussed. The refractive index of arc plasma in two conditions is compared: 1) only the first ionization is considered and 2) both the first and second ionizations are considered. In order to facilitate plasma temperature reconstruction, two corresponding refractive index models are deduced. For the sake of making this study universal, both the monatomic and dual-atomic molecule arc plasmas are chosen as typical examples for theoretical deduction and analysis. A condition, which can be adopted to estimate whether the second ionization should be considered in temperature reconstruction, is proposed. Finally, an argon arc plasma is chosen as an example for experiment, and the experimental results match well with the theoretical analysis. This study is crucial to arc plasma's optical diagnosis, which is based on the measurement of the refractive index.

Using the device for ion velocity imaging, the laser frequency is doubling with the wavelength in the region of 492-523 nm, and the laser after frequency doubling was used as the light source. The ion spectrum of methyl iodide parent molecular (CH3 I+) in the range of 76 500-81 120 cm(-1) was obtained by the way of two-photon ionization, with a very high-resolution. The mechanisms of the methyl iodide molecule two-photon ionization were also described, the CH3 I+ spectrum obtained in the experiment was marked based on Rydberg formula and the quantum defect, the split arising from p series, d series and f series levels was also explained, and the spectral assignment showed that the two-photon ionization of methyl iodide molecule can not only be used to observe the reported characteristics of single photon ionization, but also can find some transitions which is forbidden in the single photon ionization, such as f series transitions.

Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmospheric CO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate change on this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarized the research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.