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61.
单嘴精炼装置真空室内卷渣水模型研究 总被引:1,自引:0,他引:1
本文针对长城特殊厂单嘴精炼装置进行了真空室内加渣精炼的卷渣水模型研究。在试验的基础上,首先讨论了真空室内卷渣现象的工艺过程,然后进一步得出了临界吹气量的表达式。研究结果为工业性生产进一步提高钢的质量打下了基础。 相似文献
62.
LAERTE DAGHER CASSOLI PAULO FERNANDO MACHADO ANA CAROLINA DE OLIVEIRA RODRIGUES ARLEI COLDEBELLA 《International Journal of Dairy Technology》2007,60(1):44-48
Milk samples were collected in the dry season ( n = 155) and in the rainy season ( n = 68) to establish a correlation between electronic flow cytometry and standard plate count for the determination of total bacterial count of raw milk. Results were expressed in individual bacterial count (ibc) and colony forming unit (cfu) for electronic flow cytometry (Bactocount) and standard plate count, respectively. The accuracy of Bactocount, denoted by the residual standard deviation ( s ( y,x )), was 0.309 log cfu/mL. The predictive interval of estimated values was broad and it is suggested that total bacterial count should be expressed in ibc without transformation to cfu. 相似文献
63.
本文提出了一种采用悬挂靶的流量传感器,并对其工作特性进行了理论分析及试验研究,这种传感器具有很好的低流速(流量)测量特性,并且具有易于交换量程,工作可靠等优点,试验表明,悬挂靶式流量传感器可测量流速低于1m/s的空气管流。 相似文献
64.
本文以TEM和XRD为主要手段,研究WC-TiC-Co硬质合金(YT14)在直接淬火后WC相的微观结构和微观应力,比较了常规烧结态与淬火态试样WC相之间的差异,探讨了直接淬火对合金力学性能的影响。结果表明,在保持合金其他性能不降低的同时,直接淬火的抗弯强度比常规烧结提高28%左右。并首次发现,经直接淬火热处理的YTI4合会中与Co相相邻的WC晶粒边界出现滑移台阶,这是淬火过程中热应力使WC晶粒内位错在{0001}密排面聚集,并可能沿{0001}<1120>易滑移系统强滑移的结果。直接淬火试样的微观应力比重新加热淬火的低。 相似文献
65.
《Optimization methods & software》2012,27(4):573-585
Interior point (IP) algorithms for Min Cost Flow (MCF) problems have been shown to be competitive with combinatorial approaches, at least on some problem classes and for very large instances. This is in part due to availability of specialized crossover routines for MCF; these allow early termination of the IP approach, sparing it with the final iterations where the Karush Kuhn-Tucker (KKT) systems become more difficult to solve. As the crossover procedures are nothing but combinatorial approaches to MCF that are only allowed to perform few iterations, the IP algorithm can be seen as a complex ‘multiple crash start’ routine for the combinatorial ones. We report our experiments of allowing one primal-dual combinatorial algorithm to MCF to perform as many iterations as required to solve the problem after being warm-started by an IP approach. Our results show that the efficiency of the combined approach critically depends on the accurate selection of a set of parameters among very many possible ones, for which designing accurate guidelines appears not to be an easy task; however, they also show that the combined approach can be competitive with the original combinatorial algorithm, at least on some ‘difficult’ instances. 相似文献
66.
Computational Fluid Dynamics (CFD) simulation is one of the important methods to study the performance and in-fluencing factors of turbine flow sensors. According to the working characteristics of the turbine flow sensor, the passive simulation method based on the six degrees of freedom (6-DOF) model and dynamic mesh is proposed in this paper. The reliability of the simulation method is verified by steady-state experiments and unsteady-state experiments. The results show that the trend of meter factor with flow rate acquired from the simulation is close to the experimental results, and the deviation between the simulation result and the experiment result is low with a maximum deviation of 2.88%. In the unsteady simulation study, the impeller speed changes with the inlet velocity of the turbine flow sensor, which has a good follow-up. The passive simulation method can be used to predict the dynamic performance of the turbine flow sensor. 相似文献
67.
68.
无损检测的质量控制技术 总被引:1,自引:0,他引:1
以控制无损检测中的误判为例,介绍了质量控制技术在无损检测质量管理工作中的应用.首先利用流程图发现出现误判问题的产生环节,即缺陷的定位或定量错误.然后利用两图一表(因果图、排列图和检查表)分析引起缺陷定量或定位错误的原因.最后制定了防止误判产生的对策表.采用质量控制技术可以实现无损检测质量的持续改进. 相似文献
69.
The gravity flow characteristics of pharmaceutically important granules were studied in a cylindrical hopper with attachable orifice disk at the bottom. Results indicate that materials property and orifice diameter play key role in determining mass flow rate while keeping environmental condition (temperature) at fixed range. A new dimensionally analyzed equation was developed to predict gravity flow of pharmaceutically important granules. The developed correlation agreed well with the experimental data. Calcium gluconate and lactose were used for preparing granules. Generally, glidant/lubricant materials are added to pharmaceutical granules during tablet manufacturing process, in order to improve physical property of granular material. Hence, the effect of glidant/lubricant on mass flow of granules through hopper was also studied. Magnesium stearate (1.5%) was added as glidant before granulation. 相似文献
70.