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81.
从原料与生产工艺过程分析了瓷质势光砖批量色差产生的原因,并提出了相应对策,为生产质量佳化提供一定的参考。 相似文献
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指针推进移动性管理策略中指针链长度的概率 总被引:7,自引:1,他引:6
为了降低移动通信网络中位置跟踪操作的代价,指针推进策略被提出.显然,指针链长度的确定对这一策略的有效应用是至为重要的.已有论文假定移动台在位置区的逗留时间服从指数分布的条件下,对指针链的长度进行研究,但指数分布的特殊性,限制了其研究结果的应用.本文推广了上述结果,研究了移动台在位置区的逗留时间服从一般概率分布的指针推进策略,通过构造向量马氏过程,利用密度演化方法,导出了指针链长度的概率公式,这个公式可用于对各种指针推进策略性能的评价. 相似文献
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86.
Using the focal mechanisms of earthquakes taken place from 1950 to 1996, the type and direction of principal strains were established, which made it possible to determine the volume stress-strain state of the south-east flank of the Baikal rift zone on the basis of the inverse problem solution. The variations in the stress-strain fields and spatial distribution of the stored potential energy density were found by the displacements of the daylight surface points in Tunkinsk geodetic proving ground in 1975 - 1986. 相似文献
87.
应用统计控制图法,选用平均值——标准差、平均值——极差控制图法,控制24^#坝粘土填筑干密度值及施工偶然异常波动,早期提出警报,以保证土坝的施工质量。 相似文献
88.
Novel polyurethane insulating coatings were prepared from the reaction of glycerin‐terminated polyurethane prepolymers (GPUPs) and a blocked isocyanate curing agent (BIC). The GPUPs were prepared from the reaction of one equivalent of polycaprolactone polyol (CAPA 210) with an excess amount of 4,4′‐methylene bis(phenyl isocyanate) (MDI) and subsequent reaction of the NCO‐terminated polyurethane with glycerin. The BIC was prepared from the reaction of trimethylol propane (TMP), toluene diisocyanate (TDI) and N‐methylaniline (NMA). The polyols and curing agent were characterized by conventional methods while the curing condition was optimized via gel content measurements. The curing kinetics of the polyurethane coating were investigated and the kinetic parameters derived. The crosslink densities of the samples were determined via the equilibrium swelling method, using the Flory–Rehner equation. The relationships between the crosslink density and the electrical, physical, mechanical and dynamic mechanical properties of the coatings were also studied. Copyright © 2005 Society of Chemical Industry 相似文献
89.
RRN Sailaja 《Polymer International》2005,54(12):1589-1598
Lignin was graft copolymerized with methyl methacrylate using manganic pyrophosphate as initiator. This modified lignin was then blended (up to 50 wt%) with low density polyethylene (LDPE) using a small quantity of poly[ethylene‐co‐(glycidyl methacrylate)] (PEGMA) compatibilizer. The mechanical properties of the blend were substantially improved by using modified lignin in contrast to untreated lignin. Differential scanning calorimetry studies showed loss of crystallinity of the LDPE phase owing to the interaction between the blend components. Thermogravimetric analysis showed higher thermal stability of modified lignin in the domain of blend processing. This suggested that there is scope for useful utilization of lignin, which could also lead to the development of eco‐friendly products. Copyright © 2005 Society of Chemical Industry 相似文献
90.
Colour Centres and Energy Transfer in BaF2-xClx:Eu2+ Phosphors 总被引:1,自引:1,他引:0
The optical absorption spectra of BaF2-xClx:Eu2 after ultraviolet (UV) light excitation were investigated.The differences between the absorption spectra after and before excitation (DAS) were observed.The DAS increase at both the high and the low energy side of F band in BaF2-xClx:Eu2 after 245 nm UV light excitation.The bleach effect of UV light and the absorption of electrons in the valence band may account for the former and the formation of Fa centres (association of F(Cl-) centres), whose absorption band matches the HeNe laser better, may explain the latter.In the write-in process, the transfer of electrons is via tunneling.In the readout process, the transfer of electrons captured in F(F-) and Fa centres is more likely via tunneling, and that of F(Cl-) centres is more likely via conduction band. 相似文献