Abstract: An oil-gas well, a well cementation method, and a cement composition are provided. The oil-gas well has a well body, a sleeve disposed in the well body, and a cement slurry cured product disposed between the well body and the sleeve. Due to the strength and toughness of the cement slurry cured product, at least part of the sleeve is a non-metal sleeve. By selecting specific cement, the cured product of cement has excellent mechanical strength and toughness, and is mated with the non-metal sleeve to achieve well cementation.

Abstract: The disclosed is a piezoelectric phase shifter, which comprises: an input part for inputting input voltages; an output part for outputting output voltages; and a control part for tuning phase difference between the output and input voltages, which are made of a piezoelectric ceramic plate. Further, the input, output and control parts are separated by insulating gaps respectively. The wide phase shift range and good ability to manage high power and relatively high energy transmission efficiency may be obtained by the disclosure.

Abstract: The disclosed is package structure for a piezoelectric transformer, which comprises: a shell for supporting the piezoelectric transformer at its node plane; a plurality of electrical connection frames which are fixed on the shell for connecting with electrodes of the piezoelectric transformer and conducting heat from piezoelectric transformer by connection points arranging along the electrical connection frame; and a plurality of connection pins deposited on the electrical connection frames for connecting to the outside circuit. Further, the shell has a wedge structure part which fixes the piezoelectric transformer at its node plane. Correspondingly, a package method for a piezoelectric transformer is also disclosed. Thus, the structure and package method allow a piezoelectric transformer to vibrate freely and have good heat management.

Abstract: The disclosed is a piezoelectric phase shifter, which comprises: an input part for inputting input voltages; an output part for outputting output voltages; and a control part for tuning phase difference between the output and input voltages, which are made of a piezoelectric ceramic plate. Further, the input, output and control parts are separated by insulting gaps respectively. The wide phase shift range and good ability to manage high power and relatively high energy transmission efficiency may be obtained by the disclosure.