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When a dump truck brakes, it is difficult to effectively absorb the braking energy due to the transient mutation of braking energy. At the same time, braking energy production is too high to store easily. Focusing on these problems, this paper proposes a new type of two-stage series supercapacitor and battery (SP&B) hybrid energy storage system (ESS). Using the characteristics of supercapacitors, which can charge and discharge quickly with large currents, the system combines the supercapacitors with a battery with a high energy storage capacity. This allows sudden large currents to be absorbed and released rapidly, while large amounts of energy can be stored. This system can also reduce the charge and discharge times of the SP&B to meet the working requirements of dump truck braking while improving the service life of the system. After completion of the research and implementation of the proposed SP&B hybrid ESS, a laboratory dynamic model was set up as an experimental platform and vehicle operation experiments were performed. The obtained results show that the energy recovery efficiency of the hybrid ESS can reach 53.5%, which can realize both security and stability for dump truck braking energy recovery and utilization (BER&U) systems.

The Digital Signal Processor （DSP） has a mature and extensive application in the control and protection of medium and low voltage and medium and small power electronic devices, but there are some shortcomings in the control and protection application of high voltage and high power electronic devices, such as single time scale and difficulty in increasing the controllable semaphore. Aiming at high voltage and high power electronic devices, this paper designs a multi-time scale controller based on DSP, FPGA, and CPLD. Among them, DSP completes millisecond algorithm operation and logic control; FPGA performs microsecond AD sampling and PWM signal generation; CPLD realizes signal level PWM signal detection and fault blocking. The main control board and peripheral plug-in board are separated on the controller hardware to improve the expansibility of the controller. Finally, the feasibility of the controller design is proved by experiments.

New boronoalkoxycalix[4] arenes were synthesized by allylation, alkylation, hydroboration and hydrolysis of 25,26,27,28-tetraydroxycalix[4] arene, and identified by elemental analysis, IR, 1H NMR, 13C NMR, 11B NMR, Ms and UV spectra. The data of UV and fluorescence spectra showed that tetrapropoxycalix-[4]arene triboronic acid could coordinate significantly with monosaccharides.

A variety of 2-arylnaphtho[1,2-d]oxazole derivatives were efficiently synthesized in moderate to high yields by the reaction of aromatic aldehydes with 1-amino-2-naphthol derivatives in the presence of triethylamine in refluxing ethanol in air. Seven new 2-arylnaphtho[1,2-d]oxazole derivatives were obtained and characterized by the spectral data and elemental analysis. In addition, the X-ray crystal structures of 2-[4-(N,N-dimethylamino)phenyl]naphtho[1,2-d] oxzole (3d) and 1,1′-bis(naphtho[1,2-d]oxazol-2-yl)ferrocene (3n) have been determined.

A series of new asymmetric diaryltellurium dichlorides were synthesized by the transmetallation reaction of Schiff-base-type arylmercury compounds with 4-ethoxyphenyltellurium trichloride. All the asymmetric diaryltellurium dichlorides prepared were characterized by elemental analysis, IR, 1H nuclear magnetic resonance and mass spectroscopy. The crystal structure of (4-ethoxyphenyl) [(2-benzylideneamino-5-methyl)phenyl]tellurium dichloride shows that the coordination on tellurium can be considered as essentially pseudo-octahedral, with lone pair electrons occupying the forth equatorial site. The TeN distance of 2.905(2) A is shorter than the sum of the van der Waals radii of Te and N (about 3.7 A), indicating the substantial secondary intramolecular coordination between Te and N. The N → Te intramolecular coordination holds the Schiff base moiety in near-planar geometry.

The transmetallation reaction of 14 Schiff-base-type arylmercury compounds with metallic tin has been carried out in refluxing xylene. It was found tha