A perturbational h4 compact exponential finite difference scheme with diagonally dominant coefficient matrix and upwind effect is developed for the convective diffusion equation. Perturbations of second order arerted on the convective coefficients and source term of an h2 exponential finite difference scheme proposed in this paper based on a transtormation to eliminate the upwind effect of the convective diffusion equation. Four numerical examples including one to three-dimensional model equations of fluid flow and a problem of natural convective heat transfer are given to illustrate the excellent behavior of the present exponential schemes. Besides, the h4 accuracy of the perturbational scheme is vernfied using double precision arithmetic.

本文通过研究人与环境的辩证关系，提出了物质生产，人的生产和环境生产是可持续发展系统的基本模型，分析了三种生产之间的和谐关系，并对深化环境影响评价、开展环境建设、建立新伙伴关系等问题进行了探讨。

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本文界定环境哲学的基本范畴框架，以“天人合一”和“主客恶性二分”分别概括中国和西方的传统环境形上学特征，分析环境哲学的源流及其在当代可持续发展要求下的学科建构。