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71.
发射药加速寿命试验的相关性研究 总被引:5,自引:0,他引:5
用Spearman的秩相关检验法和相关系数法定量地分析了某种发射药温度单应力加速寿命试验与现场贮存试验之间的相关性。结果表明,两者显著相关。给出了相关方程及两者之间的加速系数。 相似文献
72.
73.
In this paper, another achieved example of Lunt's theory of chemical reactions in electrical discharges is emphasized. From an economic viewpoint, it is shown for a given mean value of the plasma temperature that the ozone yield of an air-fed cold plasma reactor presents an optimal value depending on the reduced electrical field, as expected from theoretical developments. 相似文献
74.
Effect of additives on formation of natural gas hydrate 总被引:1,自引:0,他引:1
The formation of natural gas hydrate (NGH) is studied in this work. Kinetics data of hydrate formation with no agitation were collected at various concentrations of the aqueous solutions with different additives such as alkylpolyglucside, sodium dodecyl benzene sulfonate and potassium oxalate monohydrate. Various kinds of additive increased the formation rates of NGH and its storage capacity and reduced the induction time of NGH formation. Moreover, the storage capacity, the induction time and the hydrate formation rate were influenced by the concentration of the aqueous solution. 相似文献
75.
Kathy A. Northcott Ian Snape Peter J. Scales Geoff W. Stevens 《Chemical engineering science》2005,60(24):6835-6843
Sludge reduction and dewatering is an important aspect of water and waste water treatment. This is especially true in the case of Australia's Antarctic contaminated site remediation program, where the reduction in volume of wastes to be returned to Australia can lead to significant transport and handling cost savings. The dewatering characterisation of water treatment sludges from an Antarctic contaminated site was conducted using a theory of suspension dewatering developed by Buscall, Landman and White. This theory uses fundamental material properties of compressibility and permeability to determine the diffusivity of a suspension. Diffusivity is a useful property that can be used to directly compare the dewaterability of various sludges. In this investigation, several water treatment sludges were collected and characterised in the field to determine the impact of temperature and additives on compressibility, permeability and diffusivity. The Antarctic sludges were found to be less compressible and less permeable than materials such as mineral suspensions and alum water treatment sludges. Compressibility was found to decrease with the addition of powdered coagulation aids such as bentonite and chitosan. 相似文献
76.
通过对原可行性研究报告中的锅炉房用煤采用筒仓群贮存方案的了解、分析、比较后,提出了采用矩形库贮存煤的优化方案设计的成果。 相似文献
77.
针对目前冷轧薄板厂生产流程复杂、大量的多品种小批量合同并线生产,导致难以制定生产计划的问题,本文提出了混合模型子空间聚类(Subspace clustering mixed model,SCMM)方法,以合同中待加工钢卷的宽度、冷轧机组的入口厚度、 出口厚度以及合同的交货期为约束,对待生产合同进行组批. 依据冷轧厂实际生产过程,将冷轧机组视为核心节点,考虑准时交货、 在制品库存和生产流向产能分配的要求,对组批后的生产合同建立全流程合同计划模型,并且利用提出的时间段蚁群算法(Time-section ant colony optimization,TSA),制定合同计划.利用生产过程的实际数据测试,本文的方法优于人工排产,可以满足制定冷轧薄板全流程生产计划的要求. 相似文献
78.
聚四氟乙烯烧结成型的制备工艺 总被引:6,自引:0,他引:6
对聚四氟乙烯(PTFE)进行了压制试验和烧结试验,讨论了成型压力与试件的致密度、压缩强度以及压缩模量之间的关系,且对不同烧结工艺下试件的压缩强度进行了分析,得到较合适的成型压力和烧结工艺。结果表明:咖材料的压缩强度随压制压力的升高而减小,压缩模量随压制压力的升高而增加;闻的成型压力为27.5MPa,烧结温度380℃,保温时间4h。 相似文献
79.
The Hadoop Distributed File System (HDFS) is designed to run on commodity hardware and can be used as a stand-alone general purpose distributed file system (Hdfs user guide, 2008). It provides the ability to access bulk data with high I/O throughput. As a result, this system is suitable for applications that have large I/O data sets. However, the performance of HDFS decreases dramatically when handling the operations of interaction-intensive files, i.e., files that have relatively small size but are frequently accessed. The paper analyzes the cause of throughput degradation issue when accessing interaction-intensive files and presents an enhanced HDFS architecture along with an associated storage allocation algorithm that overcomes the performance degradation problem. Experiments have shown that with the proposed architecture together with the associated storage allocation algorithm, the HDFS throughput for interaction-intensive files increases 300% on average with only a negligible performance decrease for large data set tasks. 相似文献
80.
Granados M. López Galisteo F. Cabello Lambrou P. S. Alifanti M. Mariscal R. Gurbani A. Sanz J. Sobrados I. Efstathiou A. M. Fierro J. L. G. 《Topics in Catalysis》2007,42(1-4):443-447
The chemical nature of P-containing species of varying concentration present in CeO2 after impregnation with (NH4)2HPO4 and calcination at 1273 K, and their effects on the oxygen storage and release (OSR) properties of ceria are reported for
the first time. The samples were characterized by different techniques and the results were compared with those recently reported
on the same samples but calcined at 873 K. When P-containing ceria solids were calcined at 1273 K, CePO4 (monazite) was the predominant P-containing species on the surface of ceria, confirming previous studies that showed that
monazite exists for those samples in which the surface P loading (P atoms per nm−2) is larger than 5.5. For lower surface P concentrations, isolated orthophosphate units are present at the surface and within
the subsurface region of the solid. Severe sintering of CeO2 after calcination at 1273 K resulted in P concentrations >5.5 P atoms·nm−2 in all samples. Isolated PO4 units that could initially be present in the samples calcined at 873 K nucleated and CePO4 was formed when samples were calcined at 1273 K. OSR properties of CeO2 deteriorated progressively when P loading increased due to the presence of larger crystals of the very stable Ce(III) phase
of CePO4 at the surface of the P-containing ceria solids. 相似文献