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51.
Migrant resettlement is essential to the success of the Three Gorges Project (TGP),and the smooth implementation of resettlement is ensured by the resettlement planning and effective organization management.In the process of resettlement planning and implementation,systematic legislation and document support system is established;environmental capacity analysis and assets appraisal methods are introduced;resettlement sites are selected through in-depth analysis and comparison;the relationship between resettlement compensation and local development is correctly understood and considered,and reasonable resettlement schedules are well prepared.Through the establishment of efficient management system and capital management mode of "static control and dynamic management",as well as the timely adjustment of plan according to actual situations,the resettlement is accomplished smoothly.Thus,the social stability of the reservoir area is ensured;the economic development of reservoir area is promoted,and it has promoted successfully the improvement of legislation,regulations and techniques for land requisition and resettlement.The paper also discusses the theory and prospective work of resettlement.  相似文献   
52.
To reduce surface depression of a bloom, the primary cooling intensity was decreased, and the water distribution of mold wide and narrow faces was optimized. The length of secondary cooling zones and the specific water flow were increased, and the water flow distribution among the secondary cooling zones was adjusted to eliminate central defects, such as center looseness, central segregation, and center line cracks. The operation showed that the proportion of surface depression decreased from 37.22% to 2.87%, whereas the proportion of center looseness for 〈1.0 increased from 79.71% to 90.70%, the proportion of central segregation for 〈0.5 increased from 1.45% to 44.19%, and the proportion of center line cracks that are free increased from 39.13% to 62.79%. The qualified blooms are delivered to produce 310 Z-beam, whose yield strength is greater than 450 MPa.  相似文献   
53.
A modified temperature-phase transformation field coupled nonlinear mathematical model was made and used in computer simulation on the controlled cooling of 82B high-speed rods. The surface temperature history and volume fraction of pearlite as well as the phase transformation history were simulated by using the finite element software Marc/Mentat. The simulated results were compared with the actual measurement and the agreement is good which can validate the presented computational models.  相似文献   
54.
On the basis of the effect of carbon precipitation on the microstructure and properties of steel products below A1 temperature, a new thermal treatment method (temper-rapid cooling process) was studied. By the temper-rapid cooling process, the yield strengths of the high strength low carbon (HSLC) steel ZJ330 and SPA-H produced using the compact strip production (CSP) process increased from 340 to about 410 MPa and from 410 to about 450 MPa, respectively. The results indirectly indicated that there existed nanoscaled iron-carbon precipitates that have obvious precipitation effect on low carbon steel produced by CSP. The prospect of application is discussed.  相似文献   
55.
The functioning mechanism of groundwater and its make-up water in the process of ground subsidence was studied from such three aspects as osmotic corrasion, osmotic pressure effect and concretion effect. As to osmotic corrasion, its forming conditions, mechanical mechanism and process were analyzed. As to osmotic pressure effect, it was mainly studied from hydrostatic pressurizing effect, sop softening effect and negative pressure sealing effect. Through concretion and saturation of soil, the factors of concretion settlement were analyzed. The results showed that both groundwater and its make-up water are important triggering factors to ground subsidence.  相似文献   
56.
The effects of quenching temperature, cooling pattern, temper temperature and temper times on the structure and properties of high speed steel (HSS) rolls have been investigated. The results show that, when the quenching temperature is lower than 1050℃ the hardness of HSS increases with the quenching temperature increasing in oil cooling, but when the quenching temperature exceeds 1100℃ the hardness decreases. In the conditions of salt bath cooling and air cooling, the effect of quenching temperature on the hardness is similar to the above law, but the quenching temperature obtaining the highest hardness is higher than that in oil cooling. When the temper temperature below 350℃ the hardness of HSS has a little change, when above 475℃ the hardness will increase with the temper temperature increasing, and the highest hardness is obtained at 525℃. When the temper temperature continues to increase, the hardness decreases. Twice temper has little effect on the hardness, but three times temper decreases the hardness.HSS in air cooling has lower hardenability, oil cooling can easily produce crackle, and HSS quenching in salt bath has high hardenability and excellent wear resistance.  相似文献   
57.
当Zn-Cu伏打电池处于缓慢、均匀稳定放电状态时,Joule热电阻RJ不等于Ohmic电阻R.RJ涉及由电流I所带的离子,而R则涉及电解质内所有离子.  相似文献   
58.
Heat conduction in oxygen probe was analyzed by means of non-steady state method and measured using "double probe" arrangement. The results showed that during the response process the thermal emf was decreased exponentially with the time and in case of low oxygen level the Seebeck coefficient and thermal conductivity of solid electrolyte agreed well with those in literatures.  相似文献   
59.
2.3[PtA_2X_2]类络合物抗肿瘤活性及毒性的研究为了获得低毒—高效的第二代抗肿瘤的铂金络合物,美国国际肿瘤研究所以顺铂作对照用各种不同的铂金络合物对黑瘤B_(16),乳房的CD8F_1,结肠的38,白血病的L_(1210),路易斯肺瘤等进行比较(表8),发现了它的抗肿瘤活性方面的差别。Bradner等人也作了相似的试验。其它科学工作者们也在努力寻找第二代的铂金类抗癌络合物,并作了有关的毒性试验(表9)(表10)。  相似文献   
60.
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