较系统，扼要地回顾了作者20余年来在压电式传感器与测力仪，压电式执行器等方面的理论研究与产品开发情况。其中对压电效应的理论研究成果。如切向灵敏度分布。石英晶体扭转效应。多种能量间的物性效应等。作了比较详细的介绍。对所研发的压电式传感器与测力仪产品作了宏观介绍。最后，对作者目前在上述领域所做的工作和对未来研究工作的想法作了简要阐述。

提出晶体四维状态效应新模型。重点分析了机电耦合效应与电磁效应的相似性。从而提出机电耦合二次、三次……感生效应的概念，以压电效应为例。从定性与定量两方面要析其变化规律。并通过静态下的实验给予证明。机电耦合大于等于二次感生效应的存大与应用，对研究与开发新型可逆变换型传感器、实现传感器与执行器集成化与一体化均具有理论指导意义。

The torsional effect of a piezoelectric quartz disc and the distribution of torsion charge sensitivity are first investigated in this paper. The torsion stresses of a circular quartz disc are deduced by using the theoty of anisotropic elasticity, and then throuth the Maxwell electromagnetic theory and piezoelectricity the distribution of bound volume and surface charge densities is computed. In order to make use of the torsional effect of a quartz disc and redues the cross talk, the distribution of torsion charge sensitivity is investigated theoretiaclly by means of coordination transformation and verified experimentally. Based on theoretical analyses of the bound charge densities and torsion charge sensitivity, the detection electrodes are effectiely arranges on the surface of the piezoelectric disc. The theoretical and experimental results show that the charge measured is linear with the torque applied and the torsion quartz measuring cell is only sensitive to torque that is independent of axial and radial force.

On the basis of the models adopted by Heckmann in 1925 and Thurston in 1994 describing physical effects in crystals, the first author established an expanded model at the beginning of 1999 describing the physical effects involving conversions among mechanical, electric, thermal and magnetic energies. In this thesis the authors investigate further to establish a more complete model endeavoring to include and explain the numerous physical effects of crystals explicitly. The principal effects and the coupled effects are illustrated in diagrams and expressions have been deduced analytically with the help of the thermodynamic method. A general expression for concerning physical effects in crystals is reached which can be seen as a natural deduction fron Onsager's theory. The new model will be helpful in the understanding of knowledge on physical effects and will be of great significance in investigations on sensors, actuators and senactuators.