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71.
通过对南(昌)长力钢铁公司2号铸坯机以及棒材生产线轧钢产能分析,优化转炉2号铸坯机一轧钢工序产能合理匹配;提高热送热装率的优化技术,该技术的应用不仅提高了棒材生产线生产能力而且节约能源。 相似文献
72.
In industrial fluid cokers the feedstock, consisting of heavy bituminous hydrocarbons, is atomized with steam and injected into a hot fluidized bed of coke. Good and uniform contact of the liquid droplets with the solid particles is required to provide heat for the cracking reactions while minimizing mass transfer effects. Experiments in a pilot plant coker have suggested that the initial particle/liquid mixing, in the spray jet, is rather poor. Experiments in a X-ray scanner showed that liquid droplets and entrained particles accumulate just below the tip of the jet plume to form agglomerates.An experimental technique was used to quantitatively determine the quality of mixing with a variety of nozzle configurations including several novel designs. By improving spray stability, redistributing liquid droplets to the solids-rich region of the jet and increasing the surface area of the gas-liquid jet-fluidized bed interface, liquid/solid contact is improved. 相似文献
73.
74.
A globally convergent algorithm for transportation continuous network design problem 总被引:2,自引:0,他引:2
The continuous network design problem (CNDP) is characterized by a bilevel programming model, in which the upper level problem
is generally to minimize the total system cost under limited expenditure, while at the lower level the network users make
choices with regard to route conditions following the user equilibrium principle. In this paper, the bilevel programming model
for CNDP is transformed into a single level convex programming problem by virtue of an optimal-value function tool and the
relationship between System Optimum (SO) and User Equilibrium (UE). By exploring the inherent nature of the CNDP, the optimal-value
function for the lower level user equilibrium problem is proved to be continuously differentiable and its derivative in link
capacity enhancement can be obtained efficiently by implementing user equilibrium assignment subroutine. However, the reaction
(or response) function between the upper and lower level problem is implicit and its gradient is difficult to obtain. Although,
here we approximately express the gradient with the difference concept at each iteration, based on the method of successive
averages (MSA), we propose a globally convergent algorithm to solve the single level convex programming problem. Comparing
with widely used heuristic algorithms, such as sensitivity analysis based (SAB) method, the proposed algorithm needs not strong
hypothesis conditions and complex computation for the inverse matrix. Finally, a numerical example is presented to compare
the proposed method with some existing algorithms. 相似文献
75.
The continuous production of hydrogen from cyclohexanes is achieved effectively using Pt/ACF (ACF = activated carbon fiber) catalysts in a fixed-bed flow reactor. The Pt catalysts are more effective than a Pd/ACF catalyst for the reaction. Besides cyclohexane, methylcyclohexane, 1,4-dimethylcyclohexane, and p-menthane can also be employed as hydrogen source in the reaction system. 相似文献
76.
Makarand Hastak Amir Mirmiran Richard Miller Ronak Shah Reid Castrodale 《Canadian Metallurgical Quarterly》2003,8(5):267-272
Precast bridges are often constructed as single span for dead load, but continuous for live load. A diaphragm connection is provided for negative moment continuity. However, the connection may also be subjected to positive moments due to time-dependent effects. Because these moments may be large enough to damage the diaphragm or even the girders, a positive moment connection is often provided. This paper reports on a study to determine the types of positive moment connections used across the country and to identify potential problems with these types of connections. A questionnaire survey was conducted to assess the state of practice for precast prestressed concrete bridges made continuous. The survey provides valuable information on this type of bridge and updates a previous survey on this subject. 相似文献
77.
78.
本文针对某一钢铁厂的一套小方坯连铸机结晶器液面自动控制系统,对其故障原因进行了深入分析,指出导致系统控制性能达不到设计要求长期无法投入运行的主要原因,并提出了相应的解决方法。 相似文献
79.
简介水泥搅拌桩的支护机理,以西涌泵站为例介绍采用格栅式水泥搅拌桩作支护结构的设计及计算方法,指出该技术能较好地解决软湿粘性土地区枢纽深基础开挖问题. 相似文献
80.
从水泥、粗细集料、水、外加剂等方面阐述了试验室对拌合站所用原材料的质量控制,论述了试验室对拌合站计量设备的质量管理,并对拌合站混凝土的质量控制、混凝土试件制作等方面进行了介绍,以真正的管理好混凝土拌合站。 相似文献