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171.
The important character of non-magnetic high manganese ZG25 Mn18Cr4 alloy is rapid work-hardening under external stress. With X-ray diffraction and TEM analysis, it is proved that the microstructures of both undeformed and deformed matrixes are austenite and carbide with some striation structure in the matrixes, the amount of stripes in the deformed matrix is obviously more than that in the undeformed matrix. Electronic diffraction analysis confirmed that the stripes in coarse austenite grains are high density lamination fault sheets. A great deal of lamination fault sheets produced by plastic deformation divides up austenite matrix, shortens the free distance of dislocation movement and results in the rapid work-hardening of ZG25Mn18Cr4 alloy. 相似文献
172.
Maintenance cost is one of the most difficult parts to calculate in variant-cost, for it s decided by the reliability of components. As an important factor of reliability, life is largely affected by maintenance. The proportional life prolonged model based on maintenance is presented firsdy. Based on this model, the function of Mainenance--Life--Cost is deduced. Which provides a new method for power plant to calculate maintenance cost more accurately. 相似文献
173.
In this paper the inevitable trend of constructing open ecosystem in modern settlement environment was discussed through the history of the settlement environment and the characters of modern settlement environment.The ecological crisis,change of the modern life and the citizens' needs and the ecological system character show,that it is important for sustainable development of the settlement environment to construct open ecosystem.The construction of modern habitation and the city room embodies the concept of open ecosystem.Then,in construction and research of modern settlement,the ecological viewpoint and method should be applied. 相似文献
174.
The authors suggest that the land storage system is beneficial not only to strengthen the country's macroscopic regulation of city land market, accelerate healthy development of city economy and increase the financial income, it can also be advantageous to carry out the economic reform and public facilities construction without a hitch. On the basis of this, in this paper, the increment of the land price and house price as well as the high risk of fund due to lack of related laws is analyzed. Corresponding legal regulations, such as polishing the legislation of land right, implementing the land utilization planning, reinforcing the legislation of city development, land requisition and countryside residential land administration are put forward. 相似文献
175.
Many factors affect the propagation of ultra high frequency(UHF) signals caused by partial discharge(PD) on the waveforms and energy of signals in transformer.To investigate the relationshi Pof factors and UHF signals,simulation model of transformer for PD study are established.UHF signals in simulation model of transformer caused by PD are calculated using finite difference time domain method.By means of amplitude and cumulative energy plot of simulation signals,and combing the measured result,the following factors:distance between PD source and detection position,different metallic conductor position around detection position and iron core and winding are researched,which contribute to comprehend the propagation characteristic of UHF signals and detect UHF signals accurately. 相似文献
176.
Frequency refining is an important spectrum analyzing tool, and is one of the main function of signal processing and the virtual instrument. This paper introduces several typical frequency refining analysis methods including DFT and multiple modulation and so on. It also probes into their advantages and disadvantages, and proposes a new frequency refining method combining subband decomposing DFT and multiple modulation, which inherits the advantages of multiple modulation, needs not to design a specific filter, reduces the amount of calculation, and is fit for real-time refining analysis. At last, it exhibits several frequency refining algorithm and their effects with applications in virtual instruments. 相似文献
177.
178.
According to the present research situation of conductive polymer materials- polyaniline (PAN) ,we reviewed the structure and properties of PAN, the effecting factors and the best conditions of electrochemical synthesis and chemical synthesis of PAN , the doping mechanism of PAN, inorganic and organic acid doping,secondary doping, the method of increase soublity and processability of PAN and the broad application of PAN. The development derection and prospect of PAN are pointed out. 相似文献
179.
Dynamic mathematical model, which is based on the character of the 200 MW tubine lbricating oil system, is established by means of modularization. On the basis of dynamic mathematical models, simulation model of the startu Pprocess of hign pressure startu Poil pum Pis created with the Visual Fortran language. The validity of this model has been verified by the simulation experiments and analysis. The simulation helps to forecast the dynamic characteristic to high pressure startu Poil pum Pand have some directive significance to design method of lubricating oil system. 相似文献
180.
A digital detecting system of the dielectric loss in the capacitive equipment is introduced based on virtual instruments.This system can real-time collect,analyze,process and storage electrical signals with National Instruments' program LabVIEW and ADLINK,s DAQ board.Through the simulation test in lab and the real test in electric substation,it is shown that this system has high accuracy on testing the dielectric loss in the capacitive equipment,the real test data is stable and the relative error of real dielectric loss is less than 5%.It is to say that this system can meet the requirement of the real on-line monitoring. 相似文献