钻井泵缸套材料磨料—腐蚀磨损实验研究

在实验研究中使用电化学测试技术和磨损试验方法,实现了磨损与腐蚀率的同时测量,提出了一种研究磨料——腐蚀磨损的定量分析方法。大量的试验结果表明,在各种介质中,磨损与腐蚀都存在不同程度的相互作用,材料的总磨损量不只是其二者的线性迭加,而产生了一增量:石油钻井泥浆介质的增量达材料磨料——腐蚀磨损总量的20％左右,碱性介质5％左右,盐性介质12％左右,而在PH5以下的酸性介质竟达80％左右,此时高铬铸铁耐磨性也不能满足钻井工况(H_2S地层),故研制陶瓷缸套是有现实意义的。     

二足机器人的姿态稳定性研究

姿态的稳定性是二足机器人在行走过程中要解决的重要问题。对在不同形态下机器人单足着地的稳定及失衡问题进行了研究。对于脚部旋转指示点F（FRI）,地面反作用力点P（COP）和质量中心投影点C（GCOM）进行了分析,可以得到二足机器人单足着地的稳定性条件。     

浅谈古建筑术语标准化建设及英译策略

基于当前的古建筑术语研究存在缺乏统一术语名称的问题,且由于古建筑自身的特点造成翻译混乱和困难的问题,文章通过例证分析造成这两个问题的原因,并提出古建筑的术语标准化建设及其翻译的几点策略。     

某军用飞机振动模态分析

采用子空间迭代法对某军用飞机自振频率和振型进行了计算与分析，得到一些有价值的结论．并为进一步研究飞机在各种动荷作用下的振动响应提供了依据．     

Air pollution and meteorological processes in the growing dryland city of Urumqi (Xinjiang, China)

Seven years (2000-2006) of monthly PM₁₀ (particulate matter, d ≤ 10 μm), SO₂, and NO₂ concentrations are reported for Urumqi, the capital of Xinjiang in NW China. Considerably high mean annual concentrations have been observed, which ranged between 150 and 240 μg m^− 3 (PM₁₀), 31 and 50 μg m^− 3 (NO₂), and 49 and 160 μg m^− 3 (SO₂). The shapes of seasonal variation of all pollutants were remarkably similar; however, winter/summer ratios of concentrations were quite different for PM₁₀ (2-3) and NO₂ (≈ 4) compared to SO₂ (up to 30). Very high consumption rates of fossil fuels for energy generation and domestic heating are mainly responsible for high annual pollution levels, as well as the (very) high winter/summer ratios. Detailed analysis of the 2000-2006 records of Urumqi's meteorological data resulted in inter-annual and seasonal frequency distributions of (a) (surface) inversion events, (b) heights of surface inversions, (c) stability classes of Urumqi's boundary layer, and (d) the “Air Stagnation Index (ASI)”. Urumqi's boundary layer is shown to be characterized by high mean annual and seasonal frequencies of (surface) inversions and by the dominance of stable dispersion classes. A further outcome of the meteorological analysis is the proof of Urumqi's strong diurnal wind system, which might have particularly contributed to the stabilization of the nocturnal boundary layer. Annual and seasonal variations of pollutant's concentrations are discussed in the context of occurrences of inversions, boundary layer, stability classes, and ASI. The trend of Urumqi's air pollution indicates a strong increase of mean annual concentrations 2000-2003, followed by a slight increase during 2003-2006. These are in strong contrast to (a) the growth of Urumqi's fleet of motor vehicles and (b) to the growing number of stable regimes of Urumqi's boundary layer climate during same period. It is concluded that the (regional and) local administrative technical countermeasures have efficiently lowered Urumqi's air pollution levels.     

Catalytic wall reactor: Catalytic coatings of stainless steel by VOx/TiO2 and Co/SiO2 catalysts

Catalytic wall (structured) reactors and structured supports are suitable to study the catalytic properties of nanosized materials. The coating of metallic (aluminum and stainless steel) plates by thin layers of active phase is presented in two cases, VO_x/TiO₂ and Co/SiO₂, catalysts used in the oxidative dehydrogenation (ODH) of propane and in Fischer–Tropsch synthesis (FTS) of clean fuels, respectively. The preparation of coated plates and their characterisation by various methods of physicochemical analysis are described. Both chemical and physical methods were used for coating. VO_x/TiO₂ layers were obtained by grafting of Ti (on Al or stainless-steel plates) and V (on TiO₂) alkoxides and use of sol–gel media or suspension. A silica primer was deposited (on stainless-steel plate) by plasma-assisted chemical vapour deposition (PACVD) onto which Co oxide and silica were coprecipitated from sol–gel. The catalytic experiments in the respective reactions were carried out in special plate reactors and compared with those of catalytic powders. The study shows that the coating of a metallic substrate by a catalyst is not straightforward and requires specific studies dealing with both chemistry (chemical affinity between substrate and catalytic layers) and catalytic engineering (catalytic performance in taylor-made reactors).     

天然光光环境模拟软件的对比研究

合理利用天然光,不仅可以改善室内的光环境,同时也有利于照明节能。为了实现良好的光环境,设计师需要在设计阶段准确把握光环境的效果、照明系统的性能和运行情况,从而进行合理的设计。随着计算机技术的发展,光环境模拟软件因其成本低、周期短和准确性高日益受到人们的重视,并在包括设计、建造、维护和管理等各阶段的建筑全寿命周期内得到了广泛应用。本文对目前常用的天然光光环境模拟软件进行了分类和简要介绍,并选择WINDOW、Sunshine、Radiance、Ecotect、Daysim等软件进行了比较分析,以便于使用者针对不同的应用进行选择和应用。     

我国近期的经济波动和宏观控制策略

确定潜在GNP是研究宏观经济波动及其控制策略的一个基本问题,但我国现有的专著和论文未见提及,国外对其确定方法也没有取得一致的意见。本文从控制工程和宏观经济理论的综合角度,对这一问题进行了以下方面的探讨,得到了一些富有意义的结果。首先,对潜在GNP提出了新的解释和新的估计方法;其次,用这种方法确定出我国近期的潜在GNP,从而划出我国1978—1989年间经济波动的幅度和周期;然后以高经济增长率和低通货膨胀率为政策目标,提出我国1990—2000年的宏观控制策略—GNP的最优轨迹,并对该轨迹下的目标均值进行了初步估计。     

双光子Jaynes-Cummings模型中运动原子与光场的纠缠特性

用量子信息理论研究具有原子运动的双光子Jaynes-Cummings模型中运动原子与光场的纠缠特性.结果表明:当运动原子的场模结构参数p取值较小时,系统的纠缠度不具有周期振荡特性,在p取值较大时,系统的纠缠度有明显的周期振荡特性,且振荡周期是原子静止情况下的2倍;在运动原子处于基态或激发态时,系统处于消纠缠状态,当运动原子处在相干叠加态时,原子才与场发生纠缠.     

我国人造板二次加工的发展历程及现状

介绍了我国人造板二次加工的发展历程及现状,指出了当前人造板二次加工发展中存在的问题及成因,分析了大力发展人造板二次加工的机遇与挑战。