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61.
赵薇 《自动化与信息工程》1997,18(3):27-31
本文主要介绍了广东南方镀锌板有限公司的1#加续热镀锌生产线退火炉所用的计算机检测及控制系统,分析了它的软件及硬件,以及它的数据采集及处理的方式,操作人员的人机接口。 相似文献
62.
本文将虚拟仪器技术与光频转换器件TSL230B相结合,设计新型浑浊度数字化测试仪.阐述该系统的工作原理、硬件构成及软件设计方案;实现浑浊度的自动在线测量.实验结果表明,该仪器数据处理能力强,图形化显示直观,保存与打印结果方便,测量的重复性好,精确度高. 相似文献
63.
运用gleeble-1500热模拟试验机November对含硼微合金钢进行了单、双道次压缩模拟,并通过非线性回归分析得到了静态与动态软化百分比(X)与变形温度(T)、变形程度(ε)、变形速率(ε·)、原始晶粒尺寸(d0)、道次间隔时间(t)之间的关系。 相似文献
64.
65.
在无线数据广播和通信系统中,为了充分利用主链路带宽,提高通信主信道的利用率,通常使用复接技术。如何适应数据源的速率变化是复接技术的关键问题,本文介绍一种自适应复接技术的设计方法及其实现。 相似文献
66.
67.
Jing Li Jiyang Wang Huaijin Zhang Shouren Zhao Xiaoxia Wang 《Materials Research Bulletin》2004,39(9):1329-1334
Single crystal of erbium, ytterbium-codoped yttrium aluminum tetraborate Er,Yb:YAl3(BO3)4(Er,Yb:YAB) has been grown by the flux method. The absorption spectrum in the visible and NIR regions of Er,Yb:YAl3(BO3)4 crystal are measured at room temperature and fluorescence spectrum of Er,Yb:YAl3(BO3)4 crystal are also measured at room temperature, excited by 976 nm laser. Not only the strong NIR emission peaks located at 1548 nm was observed, but also the visible up-conversion luminescence has been found. The specific heat of the Er/Yb:YAB crystal at room temperature is 0.81 J/g °C. 相似文献
68.
D.Q Peng X.D Bai X.W Chen Q.G Zhou X.Y Liu R.H Yu P.Y Deng 《Materials Research Bulletin》2004,39(10):1417-1429
In order to study the effects of zirconium and molybdenum ion bombardment on the aqueous corrosion behavior of zirconium, one group of specimens was implanted with zirconium ions with ions surface densities ranging from 1 × 1015 to 2 × 1017 ions/cm2 at about 170 °C, using a metal vapor vacuum arc (MEVVA) source operated at an extraction voltage of 50 kV. The other group of specimens was bombarded with molybdenum ion with ions surface densities ranging from 1 × 1016 to 5 × 1017 ions/cm2 at about 160 °C, using a MEVVA source operated at an extraction voltage of 40 kV. The valence states and depth distribution of elements in the surface of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), respectively. Polarization curves measurement was employed to evaluate the aqueous corrosion resistance of the zirconium samples in a 1N H2SO4 solution. It was found that the aqueous corrosion resistance of zirconium implanted with 5 × 1016 Zr ions/cm2 is the best in first group samples. For molybdenum ion implantation, the aqueous corrosion resistance of samples declined with raising ions surface densities. The natural corrosion potentials of zirconium samples bombarded with self-ions are more negative than that of the as-received zirconium. While, as for molybdenum ion implantation, the results are opposite. Finally, the mechanisms of the corrosion behavior of the zirconium samples implanted with zirconium and molybdenum ions are discussed. 相似文献
69.
L. Marchin 《Materials Research Bulletin》2004,39(12):1973-1983
This paper describes the synthesis of some thorium phosphate compounds with different Th/P ratio (1/2, 2/3 and 3/4) by a spray pyrolysis technique. The so-prepared rough compounds were annealed at different temperatures for 2 h and then analyzed by mainly X-ray diffraction on powder and infrared spectroscopy. Every rough compound is composed by very badly crystallized ThO2 phase polluted by carbon residue. An annealing treatment at 800 °C leads to the thorium diphosphate phase, α-ThP2O7 in every case. At 900 °C, such a phase is decomposed into a thorium phosphate diphosphate phase (Th4(PO4)4P2O7, called TPD). However, a thorium excess in the initial mixture (Th/P = 3/4) leads also to observe the ThO2 phase. The TPD phase is stable up to 1200 °C and does not react with the ThO2 compound. Beyond 1200 °C, the TPD phase is slowly decomposed into a thorium phosphate compound which should be a thorium oxide phosphate; this compound does not contain any diphosphate species. 相似文献
70.
H.P. Li 《Materials Research Bulletin》2004,39(12):1881-1894
Self-propagating high-temperature synthesis (SHS), or the so-called micropyretic/combustion synthesis, is a technique whereby a material is synthesized by the propagation of a combustion front across a powder. Heterogeneous distributions of porosities are common during self-propagating high-temperature synthesis when powders are pressed and the conventional modeling treatments thus far have only considered uniform systems. Heterogeneities in the porosity are thought to result in local variations of such thermophysical/chemical parameters for the reactants as density and thermal conductivity further changing the combustion temperature, the propagation velocity, and the propagation pattern of a combustion front. This study investigates the impact of porosity variations during self-propagating high-temperature synthesis with Ti + 2B. In addition, the simulations for the propagation of combustion fronts across a non-uniform compact where the porosity is monotonically decreased or increased along the specimens due to die wall friction are also carried out. 相似文献