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101.
高硬度耐磨电弧喷涂管状丝材的研究   总被引:2,自引:0,他引:2  
利用自熔性合金与非晶态材料的特点,研制了Fe—B系管状丝材作为电弧喷涂材料,其形成的涂层具有良好的结合强度、低的孔隙率、高的硬度和耐磨损性能。  相似文献   
102.
�·�̨ 《天然气工业》1985,5(3):37-41,83
��This work gives the concept about oil-cut,gas-cut, kick,grave kick,blowout and failure in controlling blowout and summarizes the type of failure in controlling blowout,the objective and man-made reasons causing blowout and the measures to prevent and control well blowout.  相似文献   
103.
Objective To study on the role of thymus transplantation for heart allograft in rats. Methods Vascularized heart-thymus combined transplantation was performed with microsurgical technique. Graft survival, histopathology, level of IL-2, IL-4 and its mRNA expression in serum and cardiac grafts were investigated. Results Heart-thymus combined transplantation achieved effect in the prolongation of cardiac graft survival with short-term administration of cyclosporine. Conclusions Vascularized thymus transplantation induced immune tolerance in thymectomized rats.  相似文献   
104.
With the rapid advance of silicon process technology, it is now possible to design input/output (I/O) circuits that operate at multigigabit data rates. As a result, accurate modeling and analysis of high-speed interconnect systems is essential to optimize the performance of the overall system. This paper describes the interconnect design, modeling, simulation, and characterization methodologies that are essential to achieve multigigabit data rates. It focuses on the physical layer verification and hardware correlation of functional systems and silicon to ensure robust system operation over 3.2Gb/s data rate using conventional low-cost packaging and printed circuit board (PCB) technologies. In order to capture conductor and dielectric losses, as well as other high-frequency effects of three-dimensional structures, accurate measurement-based simulation techniques that directly incorporate frequency-domain parameters from measurement or electromagnetic solver parameters into circuit simulation tools using fast Fourier transform (FFT) and bandlimiting windowing techniques are developed. Finally, simulation waveforms are correlated with prototypes at both component and system levels in both time and frequency domains.  相似文献   
105.
The growth time, growth mode and the method of preparing the supported catalysts play an important role in the growth of single-walled nanotubes (SWNTs). Their effects on the chemical vapor deposition (CVD) growth of SWNTs with MgO-supported catalysts were investigated in this study. It is shown that the growth rate of SWNTs was large during the initial few minutes of growth, however the quality of the tubes was low owing to the formation of many defects. Long term growth may favor the formation of tubes with high quality and high yield, but the introduction of other forms of carbon (impurities) is also unavoidable. There was a balance between the increase in yield and quality and sacrifice of the purity during growth of SWNTs. MgO-supported catalysts prepared by the co-precipitation method were found to be more effective for the synthesis of SWNTs than those prepared by the widely used impregnation method. The size and dispersion state of the catalyst were found to be crucial in enhancing the growth of SWNTs. In addition, growth on the surface of SWNTs over nanosized catalyst films was shown to be more favorable for the synthesis of tube products with higher quality, yield and purity.  相似文献   
106.
When numerically modeling structures with imperfect conductors or conductors coated with a dielectric material, impedance boundary conditions (IBCs) can substantially reduce the amount of computation required. This paper incorporates the IBC in the finite-element method (FEM) part of a FEM/method of moments (FEM/MoM) modeling code. Properties of the new formulation are investigated and the formulation is used to model three practical electromagnetic problems. Results are compared to either measured data or other numerical results. The effect of the IBC on the condition number of hybrid FEM/MoM matrices is also discussed.  相似文献   
107.
山东巨野国家粮食储备库天康面粉公司制粉车间始建于2000年,设计能力为处理小麦100t/d.主要设备有FMFQ10×2/6×2磨粉机8台,FS-FG6×24C高方筛3台,FQFD50×2×3清粉机2台,磨辊总接触长度12000 mm,平筛总筛理面积138.8 m2,单位磨辊接触长度12 mm/(100kg·d),单位平筛筛理面积0.14 m2/(100kg·d).麦间清理工艺(包括初清)为4筛2打2去石3磁选2着水,粉间工艺为488M1S2T4P3Br.  相似文献   
108.
龙新良 《煤炭技术》2003,22(2):49-51
总结了实际工作中防突管理的经验和问题 ,探讨了科学理论与具体实际的有机结合与统一 ,采取针对性强的有效措施 ,确保突出矿井的安全生产  相似文献   
109.
报道了以茈为荧光探针,探讨小剂量~(60)Co γ射线照射后小鼠胸腺细胞膜流动性的变化。结果表明,剂量在0.25-1.00Gy范围,胸腺细胞膜流动性降低与剂量之间呈明显线性关系。从0.50Gy起,辐照组荧光强度比值I_1/I_2与I_3/I_2与对照组的比较存有显著差异(P<0.05)。提示淋巴细胞膜流动性的变化可作为小剂量辐照早期效应的敏感指标。  相似文献   
110.
本文首先介绍了我国有色金属工业的现状以及当前世界有色金属工业发展的新格局,并分析了中国成为世界有色金属制造业基地的支撑条件,最后提出了关于建设具有特色的中国有色金属制造业基地的几点看法。  相似文献   
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