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Due to inappropriate protective measures during construction, building structures in cold regions can easily suffer from frost heaving damage during the wintering period. Such damage is relatively invisible and can hardly be detected. According to the actual engineering conditions, this paper comprehensively analyzes the destructional form of each building element at low temperatures as well as discusses the methods to detect and evaluate damage of buildings at low temperatures. The author finds that: Under low-temperature environment, punching failure often occurs between the foundation slab and bearing platform and the anchor connection between the pile and bearing platform can easily become ineffective.

A chemical method was used to deposit dicalcium phosphate dehydrate coatings on AZ91 magnesium alloy. The aim was to improve the biodegradation behavior of magnesium alloy in a simulated body fluid. The microstructures of the coating before and after immersion in the simulated body fluid were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results indicated that the dicalcium phosphate dehydrate coatings exhibited two morphologies during the pre-calcification process. The titration speed of the pre-calcification process had great influence on the morphologies of the pre-calcification coatings. As the soaking time increased, the diffraction peaks of dicalcium phosphate dehydrate disappeared and hydroxyapatite precipitated on the coated substrate surfaces. This indicates the dissolution of dicalcium phosphate dehydrate during the immersion process. The structures of the dicalcium phosphate dehydrate coatings and the formation mechanisms of the hydroxyapatite coatings were investigated in detail.

This new Vacuum Microelectronics (VME) Flat Panel Camera tube (FPC) VME-FPC, made by the same techniques used in Microtip Flat Panel Display (FPD), has been formed upon the baseplate and the faceplate, the baseplate made from the Field Emission Array (FEA) and the gates, the faceplate made from the photoconductive layer and the transparent conductive layer. The VME-FPC works when the electrons emitted from a Field Emitter Array (FEA) scan a photoconductive layer under the control of a clock. This VME-FPC offers many advantages: simple structure inside the tube, high resolution, high sensitivity, low tube volume, low energy consumption and long life, etc. We predict that the application of this type of FPC will have broad applications in high definition TV, video communication, medical apparatus and instruments.

his report are given of two experimental progresses from vacuum micro-electronics (YlkfE) field of interest. One aspect of interest is a simple method to monitor the type or nature of a diamond thin jlm resultants from the microwave plasma chemical vapour deposition (MPCVD). A very stable Raman microprobe which was in cooperation with the micro-sampling techniques plus a standard diamond sample have been used to evaluate rapidly the Jilm resultants. Combining above method with the SEA4 morphology observation, a simple and rapid monitor method to offer the nature of a film is formed without using several surface analysis equipments . Another aspect of interest is, for thejrst time in our ME area, we observed successfully a very small thin Jilm which have only about 2 micrometers diameter and was grown on the top of a trp of a silicon Jield emission array (Si-FEA). The research result and analysis in detail will be given.