Resistance reduction effect of potassium bismuth titanate doping in yttrium–manganese co-doped medium Curie temperature barium titanate lead free ceramics through improved synthesis process

Through improved synthesis process, resistance reduction effect of (K_0.5Bi_0.5)TiO₃ (KBT) doping in Y–Mn co-doped BaTiO₃ (BT) lead free ceramics was investigated. By different doping methods (doping K₂O, Bi₂O₃ and TiO₂ or synthesized KBT), medium Curie temperature (around 130 °C) lead free BT ceramics were obtained with ultra-low resistivity (13.84 Ωcm) with a temperature maintaining process at 700 °C. In this contribution, effect of sintering process and doping methods is discussed in detail.     

不同级配对微表处混和料性能的影响

微表处技术是一种性能优良的路面养护技术。首先检验了微表处用原材料的技术指标,在满足规范的要求下选择了三种不同级配,并对三种不同级配的微表处混和料的使用性能进行了比较。     

丙烯腈－苯乙烯共聚物水解磺化产物对泥浆的稳定作用

在实验室条件下对用丙烯腈－苯乙烯共聚物在硫酸存在下的水解磺化产物（ＨＳＡＳ）处理的泥浆性能进行了评定。ＨＳＡＳ处理的泥浆有较小的滤失性，较好的耐盐和抗高温性。     

Quantitative feedback theory with applications in welding

Two different control systems were developed using quantitative feedback theory for weld quality improvement. The first application to be discussed was designed for the resistance pinch welding process and uses electrode displacement and force as feedback parameters. A correlation between weld quality and electrode displacement is established for constant electrode force. The system is capable of producing repeatable welds of consistent quality, with wide variations in weld parameters. This is the first time feedback control has been successfully applied to pinch welding. The second example presented in this paper was developed for penetration control of the gas-tungsten-arc welding process. The feedback signal is obtained by measuring the amount of light emitted from the back side of the weld. Welds of constant penetration have been demonstrated in tests with travel speeds varying from 1.5 to 6 inches per minute and with 200 per cent changes in part thickness.     

风扇磨煤机ZGMn13冲击板的失效分析

ZGMn13冲击板的失效方式为不同角度的粒子撞击和冲刷，其表面可以分为三个典型的磨损区域：低角度撞击区、高角度撞击区和冲刷区。详细分析了该三个磨损区域的磨损机理。次表面分析的结果表明，在低负度撞击和冲刷条件下，高锰钢未能充分加工硬化，耐磨性提高有限。     

岩电实验饱和度模型在探明储量中的应用

合油饱和度是评价砂岩油气层最主要的参数。确定合油饱和度的方法较多，确定储层原始合油饱和度的方法主要有直接法和间接法，直接法是指应用密闭取心或油基泥浆取心井获得的资料，通过实验室分析直接获得原始合油饱和度的方法；间接法是指应用测井曲线、毛管压力曲线、类比等资料间接获得原始含油饱和度。阿尔奇公式是测井定量解释饱和度的理论基础。在实验室条件下，通过作模拟地层条件下的岩电实验，取得地层的真电阻率，对深侧向视电阻率进行厚度校正，建立正确的饱和度解释模型，使岩电实验所建立的饱和度模型在探明储量中得到了广泛的应用。     

Reactivity of steam in exhaust gas catalysis III. Steam and oxygen/steam conversions of propane on a Pd/Al2O3 catalyst

A 1% Pd catalyst (38% dispersion) was prepared by impregnating a γ-alumina with palladium acetylacetonate dissolved in acetone. The behaviour of this catalyst in oxidation and steam reforming (SR) of propane was investigated. Temperature-programmed reactions of C₃H₈ with O₂ or with O₂ + H₂O were carried out with different stoichiometric ratios S(S =[O₂]/5[C₃H₈]). The conversion profiles of C₃H₈ for the reaction carried out in substoichiometry of O₂ (S < 1) showed two discrete domains of conversion: oxidation at temperatures below 350°C and SR at temperatures above 350°C. The presence of steam in the inlet gases is not necessary for SR to occur: there is sufficient water produced in the oxidation to form H₂ and carbon oxides by this reaction. Contrary to what was observed with Pt, an apparent deactivation between 310 and 385°C could be observed with Pd in oxidation. This is due to a reduction of PdO_x into Pd⁰, which is much less active than the oxide in propane oxidation. Steam added to the reactants inhibits oxidation while it prevents the reduction of PdO_x into Pd⁰. Compared to Pt and to Rh, Pd has a higher thermal resistance: no deactivation occurred after treatment up to 700°C and limited deactivation after treatment up to 900°C, provided that the catalyst is maintained in an oxygen-rich atmosphere during the cooling.     

槽孔式水力驱动控制棒槽孔阻力系数实验研究

对槽孔式水力驱动控制棒槽对孔阻力系数进行了大量实验研究，获得了槽孔式水力驱动控制棒槽对孔阻力系数和其随槽对孔位移的变化规律，分析了槽对孔阻力系数与控制棒槽对孔结构参数之间的关系。结果表明：随槽对孔位移的增加，槽对孔阻力系数从某一较大的定值迅速降低到某一较小的定值，然后再迅速反回到初始的定值，形成一个对称的宽幅波谷；槽高使阻力系数曲线波谷幅宽发生变化，也使完全不重合段的阻力系数发生变化；随内套孔径的增大，阻力系数有所降低，其对阻力系数的影响也进一步减弱。孔径增大到一定程度，阻力系数基本不受孔径参数的影响。     

水溶性涂料使用性能研究

本文通过试验对水溶性涂料的耐盐雾腐蚀性能，耐热性能，高低温冲击性能，耐油性能，涂膜与铁基体，面漆的给合力及涂膜表面电阻进行研究，同时指出了该涂料在军用电子产品上的应用前景。     

Failure of greenstone, jasper and cataclasite aggregate in bituminous concrete due to studded tyres: Similarities and differences

In wintertime, the use of studded tyres is common in the Nordic countries, steeply in creasing road wear. Apart from reducing surface quality and durability, the airborne dust presents a potential health hazard. To reduce road wear and dust release, there is a tendency to use harder and more wear-resistant aggregate materials.On the roads in and around Trondheim, mid-Norway, three types of aggregate material are common: greenstone, jasper and ‘mylonite’, in fact a cataclasite. Extensive laboratory testing suggests that cataclasite aggregate has better wear resistance than greenstone, but less than jasper [Erichsen E, Schiellerup H, Gautneb, H, Ottesen RT, Broekmans M. Road dust in Trondheim — analysis of the mineral content of airborne dust. (In Norwegian.) Geological Survey of Norway, NGU-report 2004. 037; 2004. p. 73]. However , observations on fluorescence-impregnated plane and thin sections demonstrate that in practice, cataclasite wears faster than greenstone, which may be attributed to its oriented fabric, as opposed to the random fabric in greenstone and jasper. The original article by Rosiwal from 1896 [Rosiwal A. Neue Untersuchungser gebnisse über die Härte von Mineralien und Gesteine. Verhandlungen der kaiserlich-königlichen geologischen Reichsanstalt, vol. 17/18; 1896. p. 475–491] on abrasion hardness and anisotropy provides an elegant explanation for the field observations.