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101.
102.
CeO2和La2O3对高炉喷吹煤粉燃烧过程的影响 总被引:12,自引:0,他引:12
在模拟高炉喷吹的条件下,对添加CeO2 和La2O3的混合煤粉进行了燃烧试验,考察了稀土氧化物对高炉喷吹煤粉燃烧过程的影响,并探讨了其助燃作用机理. 相似文献
103.
This paper describes an experimental investigation into the performance and lubrication failure mechanism of precise angular-contact ball bearings treated with MoS2-sputtered film, etc. As an important executive component of various spacecrafts, there are some strict requirements on the lubrication performance of angular-contact ball bearing, but the related experimental data are rare to see in literatures. In this experiment, the lubrication performances of MoS2-sputtered ball bearing pairs were evaluated by using lifetime test as a main method, and the topographies and compositions of working surfaces were investigated through SEM, AES and EDS. The systematical experiment results reveal that the degradation and failure process of solid lubrication for such ball bearing is divided into three stages with different characters. A supposed failure mechanism has been proposed. An improved lubrication treatment based on above mechanism was conducted for the precise ball bearings, and a later test showed that long endurance life with more than 108 revolutions has been reached. 相似文献
104.
The hydration characteristics and expansion impetus of three kinds of cement paste under free-and confined-curing conditions
were investigated, which were respectively mixed with three different kinds of expansive agent at low W/B ratio. The results
show that the hydration products of pure cement paste and paste mixed with expansive agent are same, but the amount of hydration
products, un-hydrated C3S and C2S are obviously different at the same hydration age. At 3 d age, the amount of CH in pure cement paste is less than that of
paste mixed with expansive agent, but it is reverse when at 28 d age. The amount of AFt at 3d and 28d age in pure cement paste
is less than those of paste mixed with expansive agent. Regardless of under free- or confined-curing condition, the amount
of ettringite produced varies little since 3d age. The joint effect of the tumefaction of gel-ettringite due to water absorption
and the expansive pressure on the pore caused by the crystalloid ettringite is the cause of the volume expansion of cement
paste, and the former effect is much greater than the latter.
LU Lin-nu : Born in 1972
Funded by 973 High-tech Project of China (No. 2001CB610704-2) and the Natural Science Foundation of Hubei Province(No. 2002AB075) 相似文献
105.
论述了MPP系统中节点机的通信结构,以及在主控机与节点机之间实现的Message Passing通信及其通信协议。 相似文献
106.
高浓度煤粉燃烧时炉内结渣的机理分析 总被引:6,自引:0,他引:6
在分析煤粉炉结渣过程及其机理的基础上,对高浓度煤粉燃烧时易导致结渣的主要特性进行了探讨,表明还原性气氛的出现和煤粉浓缩时富铁颗粒的富集有导致和促进结渣的作用;提出了一些防止和减轻结渣的必要措施 相似文献
107.
TiO_2-云母珠光颜料复合机理的讨论 总被引:5,自引:0,他引:5
通过对云母、水合二氧化钛晶体以及二氧化钛晶体的结构和表面特性进行分析,对云母钛珠光颜料的复合机理进行了讨论。云母钛的复合过程包括物理吸附和化学吸附 相似文献
108.
李愿军 《武汉大学学报(工学版)》1997,(6)
讨论了核废物处置库地震地质评价的基本目的和任务,提出了与能动构造和设计基准地震动相关的5项评价内容,给出了它们之间的逻辑关系和评价程序. 相似文献
109.
This paper addresses the recovery of structure and motion from uncalibrated images of a scene under full perspective or under affine projection. Particular emphasis is placed on the configuration of two views, while the extension to $N$ views is given in Appendix. A unified expression of the fundamental matrix is derived which is valid for any projection model without lens distortion (including full perspective and affine camera). Affine reconstruction is considered as a special projective reconstruction. The theory is elaborated in a way such that everyone having knowledge of linear algebra can understand the discussion without difficulty. A new technique for affine reconstruction is developed, which consists in first estimating the affine epipolar geometry and then performing a triangulation for each point match with respect to an implicit common affine basis. 相似文献
110.
Robust Estimation of Rotation Angles from Image Sequences Using the Annealing M-Estimator 总被引:1,自引:0,他引:1
A robust method is presented for computing rotation angles of image sequences from a set of corresponding points containing outliers. Assuming known rotation axis, a least-squares (LS) solution are derived to compute the rotation angle from a clean data set of point correspondences. Since clean data is not guaranteed, we introduce a robust solution, based on the M-estimator, to deal with outliers. Then we present an enhanced robust algorithm, called the annealing M-estimator (AM-estimator), for reliable robust estimation. The AM-estimator has several attractive advantages over the traditional M-estimator: By definition, the AM-estimator involves neither scale estimator nor free parameters and hence avoids instabilities therein. Algorithmically, it uses a deterministic annealing technique to approximate the global solution regardless of the initialization. Experimental results are presented to compare the performance of the LS, M- and AM-estimators for the angle estimation. Experiments show that in the presence of outliers, the M-estimator outperforms the LS estimator and the AM-estimator outperforms the M-estimator. 相似文献