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71.
金属粉末注射成形粘结剂的发展 总被引:38,自引:2,他引:38
概括了金属注射成形粘结剂的功能与发展过程,并对几种典型粘结剂及其脱除工艺进行了适用性与经济性分析。 相似文献
72.
研究了葫芦岛蒙脱土的某些特征与催化活性。该蒙脱石的离子交换能力与层间距分别是75meq/100g和1.529nm,对偏三甲苯的歧化、异构化以及偏四甲苯的脱甲基、异构化都具有催化活性。这些数据表明葫芦岛蒙脱土是一种有用的催化材料。 相似文献
73.
活性炭共吸附现象对有机蒸气穿透容量的影响 总被引:3,自引:0,他引:3
在空气避有机蒸气的气相色谱分析方法研究中,为获得可靠的采样效果,探讨了活性炭对共存有机蒸气的共吸附与穿透容量的关系,试验了四种有机蒸气共存时和组分的有采样效率。结果表明,共吸附使所有共存有机蒸气的穿透容量下降,共吸附物质愈多,穿透窝量下降愈严重。对二种和四种有机蒸气的共吸附,使丙酮的穿透容量下降21.9%和41.7%,四组分共存时,丙酮,丁酮,环已酮、甲苯的穿透窝量分别为5.6、5.0、9.7、1 相似文献
74.
结合实测和试验资料,从理论上分析嵌岩灌注桩竖向承载力问题,及其各种影响因素。归纳总结了确定嵌岩灌注桩的承载力方法。 相似文献
75.
宝钢高炉高煤比的实践与探索 总被引:4,自引:0,他引:4
宝钢高炉自1992年喷煤以来,从优化喷吹煤种、控制混合煤成分、改善喷煤设备性能和操作参数、制订原燃料质量标准和重新设计高炉操作制度等方面着手,通过多年的科学探索和生产实践,从1998年6月份起,高炉喷煤比已连续5年多的时间稳定在200kg/t的水平,最高曾达到260kg/t,并且高煤比是在高产能、低燃料消耗下取得的。 相似文献
76.
77.
LigangWang ChangheChen KruseH.Kolker 《北京科技大学学报(英文版)》2004,11(4):293-296
Coal combustion technologies are changing in order to burn coal more cleanly. Many “clean combustion“ and postcombustion technologies are developed to remove SO2 and NOx gases, particulate matter during combustion, or from the flue gases leaving the furnace. This paper focuses on three types of fly ash (flue gas desulfurization (FGD) residuals, atmospheric fluidized bed combustion (AFBC) residuals and sorbent duct injection (SDI) residuals) which produced by “the clean combustion“ and postcombustion technologies. The residuals formed by FGD are PCFA (pulverized coal fly ash) grains entrained with reacted and unreacted sorbent and have lower bulk densities than PCFA grains because it contains higher concentrations of calcium and sulfur, and lower concentrations of silicon, aluminum and iron than PCFAs. AFBC residuals consist of spent bed which is a heterogeneous mixture of coarse-grained bed material and irregularly shaped, unfused, spherical PCFAs. The main crystalline phases in AFBC residuals are anhydrite (reacted sorbent), quartz and lime (unreacted sobent), calcite, hematite, periclase, magnetite and feldspars.The residuals produced by SDI contained 65%-70% PCFA with the larger sizes material being irregularly shaped, fused or roughedged. The reaction products of sorbent (portlandite and lime) included calcium sulfate (anhydrite) and calcium sulfate. The chemical properties of these residuals are similar to those of high calcium PCFAs because of the high alkalinity and high pH of these residuals. 相似文献
78.
Bukhanovskii V. V. Borisenko V. A. Kharchenko V. K. Mamuzic I. 《Strength of Materials》2004,36(2):195-202
Experimental data on the short-term strength and plasticity of niobium alloy 5VMTs of the system Nb–W–Mo–Zr in its initial state, after annealing, and with a silicide-ceramic protective coating obtained by testing in vacuum, an inert atmosphere, and in air in the temperature range from 290 to 2270 K are analyzed. The process of microcrack initiation and propagation in the protective coating and matrix is investigated in high-temperature static tension. The limiting plastic strain values have been established at which the composite retains its load-carrying capacity in high- temperature aggressive and oxidizing gas atmospheres. 相似文献
79.
Yao Yongxun Duan Zhenzhong Li Yuenan Gu Hongwei Hua Zhiqiang Luan Wenzhou Wang Yuan 《中国稀土学报(英文版)》2004,22(Z2)
LiFePO4 cathode material was synthesized by a solid-state reaction using doping several elements (Nb5 ,Zr4 ). The starting materials were mixed with a high-efficient sander and treated thermally under flowing N2. The samples were characterized by X-ray diffraction (XRD), field-emission gun electron microscopy (FEG), and their electrochemical performance was investigated in the term of cycling behavior. Room temperature discharge capacity about 140.6 mA·h·g-1 was obtained at C/5 rate. 相似文献
80.
Walter Michaeli Dirk Opfermann Thomas Kamps 《The International Journal of Advanced Manufacturing Technology》2007,33(1-2):206-211
In micro systems technology, the process of micro assembly injection moulding is used for the generation of hybrid micro systems.
With this process, more functions are integrated in less space. In the field of medical technology, miniaturisation also means
new methods of treatment with fewer side effects on the patient. New cures are developed by the miniaturisation of medical
instruments, such as keyhole surgery. For detailed investigations a specific demonstration was developed to display the potential
of micro assembly injection moulding in medical science. This part consists of a carbon-fibre reinforced PEEK puncture needle,
which incorporates three lumens. The selected materials allow use of the needle during magnetic resonance imaging. In order
to attach additional equipment a plastic connector needs to be overmoulded on the needle. The investigations focus on the
injection moulding process by characterising the influences of temperature, moulding parameters and material combinations
on the resulting bond strength between needle and connector. 相似文献