高温后花岗岩巴西劈裂抗拉实验及超声特性研究

采用非金属超声检测分析仪和液压伺服试验系统装置,研究不同温度（25 ℃～1 000 ℃)作用后花岗岩的超声特性,分析不同温度条件下花岗岩的劈裂抗拉强度。结果表明,（1）高温后花岗岩的纵波波速、超声波形以及劈裂抗拉强度都与温度的变化密切相关;（2）随着温度的增高,花岗岩试样的纵波波速和劈裂抗拉强度逐渐减小,经历1 000 ℃高温后,纵波波速下降90%,劈裂抗拉强度下降65%,并且,纵波波速和抗拉强度间存在一定的相关性;（3）超声波波形随温度升高由整齐变混乱,由密集变稀疏,尤其在800 ℃波形变化最明显;（4）花岗岩试样的热损伤不断增加,经历1 000 ℃热损伤后,试样的脆性增加,变得轻脆易碎。     

MODEL OF AGRICULTURAL ECOLOGIC-ECONOMIC SYSTEM IN THE INTERMONTANE BASINS OF XUEFENG MOUNTAIN REGION

The area of the intermontane basins in the Xuefeng Mountain region is 4,000 km2. These basins are the most favourable area for agriculture in the mountainous region. Unfortunately, in each basin the eco-environment has gradually worsened because of the irrational utilization of natural resources. A rational model of agro-ecologic- economic system of intermontane basin must be formed so as to exploit and utilize rationally the natural resources. The intermontane basins may be divided into 3 ecologic belts of agriculture. Here are some ecologic-economic problems in the development: The resources of the outer mountains lie waste, but the valley basins in centre are over-development; the low mountains and hillocks are cultivated for dry crops so that the water and soil losses are serious and the natural disasters are frequent. Therefore, the agro-economic, agro-biologic and eco-environmental subsystems form a complete agro-ecologic-economic system of intermontane basins. Developing rationally the resources     

农业区域开发与建设地理研究

农业区域开发为建设地理研究与农业生产实践相结合提供了新的领域。建设地理研究通过对农业区域开发的自然资源评价,为开展区域选择、项目布局、工程设计与实施提供定性、定量、定位的依据,从其研究的特有角度增强农业开发规划与布局的区域特色,直接参与农业开发项目的工程设计和实施,以地理学的方法切实解决农业区域开发过程中一般农业研究和工程设计所不能解决的问题。根据南方山区农业区域开发实践,建设地理应注重研究地理环境的微(小)地域分异、荒地资源的改造利用和生态环境建设等问题。     

雪峰山区山间盆地农业生态经济系统模式探讨

本文据雪峰山区山间盆地农业资源和生态环境特点,在分析与评价资源利用现状及其生态经济问题的基础上,探索了农业生态经济系统模式,设计了农业生态经济系统结构及其空间布局型式,论及了系统的“整体效应”、“边缘效应”,并设想了雪峰山区经济开发的串珠状网点模式。