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141.
Capital cost correlations are given for oil-water separators, equalization basins, primary clarifiers, clarifiers and clarifier mechanisms, reverse osmosis unit, ultrafiltration units, gravity filters and miroscreens. Data are included for raw sewage, intermediate and recirculation pumping stations and for preliminary treatment (or bar screens, grit removal, overflow and bypass chamber and Parshall flume), for grit removal, comminution and gas stripping. The correlations are accurate to ± 30%, expressed in Canadian dollars and adjusted to a Marshall and Swift value of 1000. Details as to what components are included in the cost are given. Data are given for the labour and material costs to create a working process module. For inflation indices, a critique of the Engineering News Record, EPA small city, Marshall and Swift, Chemical Engineering and Southam inflation indices suggested that the Marshall and Swift index is most appropriate for the construction and process equipment studied here. Concerning the currency exchange, for the equipment and processes in this study, equipment costs the same whether expressed directly in US or Canadian dollars. To put the current data into perspective, several hundred sources of cost data were analyzed. The major correlations are compared, on a consistent basis, with current data. 相似文献
142.
本文主要完成了液态金属钠高温沸腾实验回路的应力分析与计算,确定了回路高温区连接管系的布置型式和支吊架系统,是该回路总体设计的重要组成部分。 相似文献
143.
使用有限元程序SAP5对某新型导弹发射筒内的适配器的强度进行了计算。通过结果分析,找出了适配器危险应力点的分布规律,它对结构选型设计具有指导意义。 相似文献
144.
145.
采用大电流交流脉冲对非晶Fe78B13Si9合金进行了去应力退火。初步探讨了电脉冲加热对加热速率和该合金内应力释放、退火脆化以及最终软磁性影响的基本规律。结果表明:电脉冲加热可以得到远高于常规退火的加热速率,选择合适工艺参数可使非晶合金内应力释放90%,软磁性(H_c和B_s)达常规退火后的95%以上,与此同时使合金的延性(断裂应变ε_f)维持在0.9以上,从而有望实现非晶合金磁性与延性的合理配合。 相似文献
146.
Local stress and strain variations in the deformation zone can be ascertained by measuring hardness. Hardness is correlated
with strain and stress. The expressions discussed later are useful in determining the local variations in stress and strain
from hardness measurement. It is a simple method compared to visioplasticity. One can estimate the forces required for a forming
process. It helps in the choice of equipment, design of tooling and selection of lubricant for the particular process. 相似文献
147.
研究了55SiMnVB弹簧钢板疲劳断口特征及裂扩展过程。结果表明,喷丸强化在表层产生的残余压应力可明显提高疲劳抗力,增强裂纹闭合效应,降低裂纹扩展速度。 相似文献
148.
A. Brown 《Renewable Energy》1993,3(2-3)
The UK Government has supported a programme on Renewable Energy since 1975. In 1988 progress was reviewed and this led to some redirection of the programme with greater emphasis on the commercial development of renewables, as published in Energy Paper 55.The climate in which Renewable Energy operates has been influenced recently by a number of factors including privatisation of the UK electricity supply industry, when the Government introduced the New Fossil Fuel Obligation and publication of the Government's 1990 White Paper on the Environment which noted that the Government is working towards a figure of new renewable energy generating capacity of 1000 MW by 2000.The paper aims to give an overview of the present state of development of the renewable technologies in the UK and to discuss some of the factors - technical and non-technical - which will affect their likely future development. 相似文献
149.
J. Yu R. Brook I. Cole D. Morabito G. Demofonti 《Fatigue & Fracture of Engineering Materials & Structures》1996,19(8):1019-1029
Abstract— Duplicate tests have been performed to determine the effect of cathodic protection potential on corrosion fatigue crack growth rate of a modern offshore structural steel, produced by thermo-mechanically controlled processes. The experiments were carried out using compact tension specimens exposed to artificial seawater at 10°C and subjected to constant amplitude loading at 0.35 Hz. Reproducible results showed that the merits of cathodic protection potentials are strongly dependent on stress intensity ratio R and stress intensity range Δ K . It appears that a specific value of cathodic potential may not give comprehensive protection against corrosion fatigue within the spectrum of variable amplitude loading experienced in service. Fractography showed the initiation of secondary cracks on the fracture surface to be associated with the dissolution of calcium sulphide inclusions, regardless of imposed cathodic potential. 相似文献
150.