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MOFs have various chemical components and structures, a high-specific surface area, potential redox sites and other significant advantages, which give them broad application prospects in the field of material synthesis as precursors. In this paper, MOF materials were synthesized by the solvent method, and MOF-derived nitrogen self-doped porous carbon materials were prepared by a one-step carbonization method. The effects of carbonization temperature and time on the structure and electrochemical properties of MOF-derived nitrogen self-doped porous carbon materials were investigated. The results show that MOF-derived nitrogen-doped porous carbon has an amorphous graphite carbon structure with a large specific surface area and various pore structures. In a 6 M KOH electrolyte solution, when the current density was 1 A g−1, the MOF-derived nitrogen-doped porous carbon material exhibited a specific capacitance of 219.4 F g−1; after 5000 cycles of constant current charging and discharging, the capacitance retention rate was still 88.94%, showing excellent electrochemical performance and good cycling stability.

Metal-organic frameworks are compounds with a reticulated skeletal structure formed by chemically bonding inorganic and organic units that are widely used in many fields, such as photocatalysis, gas separation and energy storage, because of their unique structures. In this paper, we prepared a metal-organic framework [(μ2-2-methylimidazolyl)12-Zn(ii)6-H18O10]n(ZM) with well-developed pores and high specific surface area of MOFs by the solution method. And MOF-derived porous carbon was prepared by the direct charring method in an argon atmosphere using a mixture of ZM, ZM and potassium citrate as carbon precursors. Characterization analysis revealed that the maximum specific surface area of ZMPC-800-1:15 was 2014.97 m2⋅g−1, and the pore size structure was mainly mesoporous. At a current density of 1.0 A⋅g−1 the specific capacitance of ZMC-800 and ZMPC-800-1:15 was 121.3 F⋅g−1 and 226.6 F⋅g−1, respectively, with a substantial increase of 86.8%. The specific capacitance of ZMPC-800-1:15 decays to 168.8 F⋅g−1, with a decay rate of 25.5%, when the current density increases to 10.0 A⋅g−1. After 5000 constant current charge/ discharge cycles, the capacitance retention rate was still 96.41%. These results prove that the application of MOF-derived carbon materials in future supercapacitors is very promising.

This paper presents a new sensor for ECT/ERT dual-modality system which can simultaneously obtain the permittivity and conductivity of the materials in the pipeline. Quasi-static electromagnetic fields are produced by the inner electrodes array sensor of electrical capacitance tomography (ECT) system. The results of simulation show that the data of permittivity and conductivity can be simultaneously obtained from the same measurement electrode and the fusion of two kinds of data may improve the quality of the reconstructed images. For uniform oil-water mixtures, the performance of designed dual-modality sensor for measuring the various oil fractions has been tested on representative data and the results of experiments show that the designed sensor broadens the measurement range compared to single modality.

Function S-rough sets is defined by function equivalence class, function is a kind of feature. By using of function S-rough sets, this paper gives a new feature selection method, gives concepts of lower approximation features and upper approximation features, furthermore, it presents the structure of F-feature pair, gives its characteristic discussion. F-feature selection method given in this paper has gotten applied in image processing, object recognition and etc, it is becoming a new research direction in recognition theory.

In order to improve the accuracy of silicon piezoresistance pressure sensor under different temperatures, temperature compensation should be carried out. A temperature compensation system of pressure sensors is presented. The structure, hardware and software design of the system are introduced. In the hardware design, MAX1452 is used as the main compensation unit. A curve fitting algorithm based on cubic B-spline is adopted in the temperature compensation software design. The accuracy and the production efficiency of the sensors are improved. The system features in low cost, high efficiency and high accuracy. And it has great spreading value.