铁固体超强酸催化剂的改性及结构特征

用沉淀法在一定条件下制备了由硫酸根促进的以氧化铁为主要活性组分的铁固体超强酸催化剂 ,并选择了氧化镧与氧化锆作为辅助金属氧化物添加剂进行了改性。用红外光谱测定了其分子结构 ,用流动气相色谱法测定了催化剂的比表面积和孔径结构。结果表明 ,铁固体超强酸催化剂的酸强度H0 ≤ - 1 4 5 2 ,比表面积为 1 2 4 8m2 ·g- 1 ,孔径集中在 1 0～ 2 0nm ,分子为桥式双配位结构。经改性后的催化剂用于乙酸丁酯的合成反应 ,有较高的催化活性和使用寿命。     

电机中几个概念性问题的深入分析

分析了电机中铁心损耗的形成机理及其本质,讨论了直流电机电枢反应的去磁机理,明确了同步发电机准同期并列的含义,从而深刻理解有关基本概念。     

高品位印度矿粉烧结性能试验研究

为了拓宽烧结用料，达到优化烧结原料结构的目的，太钢对高品位印度矿的烧结性能进行试验研究，结果表明，配用高品位印度矿，烧结矿的性能能够满足高炉炼铁生产的要求。     

Activities of Phosphorus in Copper‐Iron Liquid Alloys Saturated with Copper‐Iron Solid Solutions

In order to determine the activities of phosphorus and iron in liquid {Cu‐Fe‐P} alloys, the two coexisting phases of liquid {Cu‐Fe‐P} alloys + <Cu‐Fe‐P> solid solutions were brought into equilibrium with a mixture of Al₂O₃ + AlPO₄ + Fe_xAl₂O₄ at temperatures of 1416K and 1526K. The oxygen partial pressures were measured with the aid of a solid‐oxide galvanic cell of the type: (+)Mo / Mo + MoO₂/ ZrO₂(MgO) / {Cu‐Fe‐P} + <Cu‐Fe‐P> + <Al₂O₃> + <AlPO₄> + <FeAl₂O₄> / Fe(‐) The equilibrium reactions underlying the experiments can be expressed by 2[P]_cu + (5/2) (O₂) + <Al₂O₃> = 2 <AlPO₄> and x[Fe]_Cu + (1/2) (O₂) + <Al₂O₃> = <Fe_xAl₂O₄> The Henrian activity coefficient referred to 1 wt pct solution in pure liquid copper could be well expressed by the formula log f_P° = (4.46±0.40) ‐ (8.67±0.59)/(T/K). The iron activities referred to pure solid iron could be formulated as log a_Fe =‐ (0.37 ± 0.12) + (500 ±200) /(T/K).     

Effects of Rare Earth and Alkaline Earth on Spheroidizing of Eutectic Carbides in Low Tungsten White Cast Iron

Tungsten Alloy White Cast Iron(TAWCI) has great brittleness and narrow application scope. The influences of Rare earth element(Ce) and alkaline earth elements ( K, Na) on the microstructures and performances of TAWCI were researched, and the idea estimating spheroidizing effect of carbides using Circular Degree (C. D) were put forward. The result shows that eutectics carbide tums into sphericity from network after modification, and carbide is refined and uniformly distributed and the C. D of eutectic carbide increases. The mechanism of carbide spheroidizing was analyzed. The impact toughness and wear resistance of TAWCI obviously improve with the rise of C. D of carbides.The service life of modified TAWCI roll is 35 % higher than that of high chromium cast iron roll, and its production cost is reduced by 25 %.     

ULTRA‐FINE TRACKING CONTROL ON PIEZOELECTRIC ACTUATED MOTION STAGE USING PIEZOELECTRIC HYSTERETIC MODEL

The tracking control accuracy of the piezoelectric actuator (PEA) is limited due to its inherent hysteresis nonlinearity. A new piezoelectric‐actuator model is synthesized based on two first‐order transfer systems in parallel with two tuned parameters determined from one experiment. Two open‐loop tracking controllers are implemented with the proposed model to compensate the hysteresis of linear positioning. Numerical simulations and experimental tests on the tracking of sinusoidal and triangular waveforms with signal frequencies ranging from 1Hz to 30 Hz are revisited and compared with the conventional Bouc‐Wen and Duhem models. Experimental results reveal that the RMS tracking error can be reduced to less than 2% of the maximum traveling distance without any feedback sensor. When a piezoelectric actuated on a two Degree‐Of‐Freedom (DOF) monolithic motion stage was employed, the RMS tracking error was 50 nm within the measured sensor accuracy.     

山西翼城冶南汉代冶铁遗址初步调查

冶南遗址位于山西省临汾市翼城县冶南村,面积约1.2 km²,考古年代为西汉。采用X射线荧光分析仪(EDX)、扫描电镜及能谱分析仪(SEM-EDS)、金(矿)相显微镜等对冶南遗址采集的6个炉渣和2个金属铁块进行了基体成分和显微组织检测分析。结果表明,6个炉渣样品为硅钙铝系低铁渣;2个铁块样品为熟铁,可能是生铁炒钢产品。判断该遗址为生铁冶炼遗址,同时也是生铁炒钢遗址。该遗址是目前山西地区确认的第一处大型生铁冶炼及炒钢的汉代官铁遗址。     

The State-of-Art and Development Trends of HSLA Steels in China

During the last decade,the adjustment of product segments always is a very important task of iron industry,and upgrading of steel products has been impelled actively by Chinese iron and steel industry.With rapidly increasing of iron & steel production,a series of research achievements have been made in the technology area of high strengthtoughness steel,and also have been applied successfully in the actual production,e.g.the technology of fine grain and ultra-fine grain steels,the technology for the control of microalloying precipitates.Further,It is an important strategic goal of "Twelfth Five-year Plan" for Chinese iron and steel industry that the adjustment of steel product segments and meeting the requirements for upgrading of domestic and oversea equipment manufactory industry.Adopting HSLA steel with better performance,instead of plain steel,could save steel consumption largely,and also release pressures from resource,energy and environment.Without doubt,it is the only way to realize the sustained development of Chinese iron and steel industry by popularizing the application of HSLA steels vigorously.     

纳米隔热材料在水泥厂中的设计应用

纳米隔热材料具有良好的隔热性能和热稳定性,在水泥厂高温部分使用可有效降低系统表面散热。本文通过建立设计模型量化散热量,对纳米隔热材料使用规格、部位作进一步优化。     

液相法制备纳米钯粉的工艺研究

采用液相法,以Pd粉为原料,分别用HCHO,HCOOM,C2H4H2O作还原剂,把钯还原成纳米粉末。通过控制反应体系的pH值、浓度、温度及还原剂的种类和还原时间来控制粉末的粒径大小及其分布.实验结果表明:利用本法制备的Pd粉粒径在9 nm~20 nm,粒度分布均匀而且重现性好,适用于制造钯银导体浆料.