A self-doping strategy is applied to prepare a multi-heteroatom-doped carbonaceous nickel selenide NiSe@C composite by introducing N and P-containing ligand hexa(4-carboxyl-phenoxy)-cyclotriphosphazene (HCTP-COOH) into a Ni-based MOF precursor. The MOF-derived NiSe@C composite is characterized as NiSe particles nested in a multi-heteroatom-doped carbon matrix. The multi-heteroatom-doped NiSe@C composite with a unique structure shows an excellent sodium-ion storage property. The Na-ion battery from the NiSe@C electrode exhibits a capacity of 447.8 mA h g−1 at 0.1 A g−1, a good rate capability (240.3 mA h g−1 at 5.0 A g−1), and excellent cycling life (227.8 mAh g−1 at 5.0 A g−1 for 1200). The prospects of the synthesis methodology and application of NiSe@C in sodium-ion batteries (SIBs) devices are presented.

According to the common Glan-Taylor prism's design feature, Fresnel formulae and Brewster's law, a novel Glan -Taylor prism was designed and fabricated. In the new prism, the structure angles of second half were modified to proper values so that extraordinary ray is incident on with Brewster angle. In order to minimize the deviation angle of the new prism, an additional angle was designed. Theory and experiments have confirmed that the transmittance of the new prism is higher than that of a common one in a wide wavelength range and the interference effect will not occur in the new prism. Experimentally, its deviation angle is smaller than 3 in the wavelength range of 540-670 nm.

In order to reduce the error caused by the change of temperature, the relation between three-in-one composite compensator's phase retardation and temperature is calculated according to the characteristic of multiple-order quartz wave-plate. The results show that the influence on phase retardation increases with the increase of temperature and order of wave-plate. The phase retardation and the angle that the second wave-plate rotates are in a linear relationship in certain ranges. However, there is also some regularity in nonlinear areas which can be determined by theoretical calculation. The calculated result is well in agreement with experiments.

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