缓冲/回填材料的热损伤与纵波速度关系研究

采用岩石力学试验系统、超声波检测仪、扫描电镜等设备对缓冲/回填材料在25℃～300℃范围内的力学特性和纵波速度进行研究。结果表明:在200℃以前,缓冲/回填材料的应力–应变曲线斜率、单轴强度随温度的上升而呈增大趋势;200℃～300℃的应力–应变曲线斜率、单轴强度随温度升高都有不同程度的降低。缓冲/回填材料的平均纵波速度在25℃～100℃时呈增大趋势,在100℃～300℃呈减小趋势。因此,纵波波速与单轴强度相关性与缓冲/回填材料的特性不同。     

The characteristics of voltage degradation of a proton exchange membrane fuel cell under a road operating environment

A real-life testing experiment of a proton exchange membrane fuel cell (PEMFC) and the basic characteristics of its voltage degradation are presented. A general package radio system (GPRS)-based remote monitoring system was used as the data acquisition method, and the non-linear regression method was used to estimate PEMFC's polarization curve within specific iso-interval periods. The voltage degradation rate was calculated using the differential method, and its average level was also analyzed. The experimental results indicated that the voltage degradation rate at a specific current density featured a bathtub-like curve, exhibiting 1) infant degradation, 2) steady degradation, 3) and accelerated degradation.     

浅探参数曲线上的圆弧螺纹编程加工

本文探讨在FANUC-0i系统的经济型数控车床上,加工参数曲线上的圆弧螺纹,作者采用宏程序复合循环嵌套的编程方法,成功完成参数曲线上的圆弧螺纹编程加工。     

Oil and the political economy of energy

The key issues concerning oil exploitation are still open for discussion: there is no agreement about where we presently stand in the world oil extraction curve, what is its exact shape, and how far can oil price grow before it changes irreversibly the world economy and consumer behavior. The paper proposes an alternative scenario to the Hubbert's bell-shaped model of oil exploitation, based on more realistic assumptions regarding political agendas in oil-exporting countries and consumer behavior dynamics in oil-importing countries. Under this scenario, the joint impact of markets and public policy in oil importing countries together with “resource pragmatism” policy in oil-exporting countries allows for a less steep oil supply curve with a much fatter tail compared to the Hubbert's model.     

Partial coalescence as a tool to control sensory perception of emulsions

This study evaluates the role of partial coalescence of whey protein-stabilized emulsions on sensory perception. The selection of fats was restricted to vegetable fats that are essentially melted at oral temperatures. The sensitivity to partial coalescence was controlled by a variation in the fat melting curve and by addition of unsaturated monoglyceride. Most fat-related sensory attributes appear to be well-correlated to an increase in viscosity and coalescence in the mouth due to partial coalescence. Moreover, it was found that in-mouth aeration induces extra coalescence, which increases the perception of fat-related sensory attributes significantly.     

顺发井田综合勘查施工中煤岩层对比

采用地震与钻探综合地质剖面定构造形态、测井曲线组合特征定层位;钻探岩性及标志层特征定深度,用这种综合岩煤层对比方法指导勘查施工行之有效。     

氮化钒生球干燥过程研究

氮化钒是VT包芯线粉芯材料的一种,使用中对其粒度有严格要求,经过破碎后会产生很多细粉,不能直接使用。为充分利用细粉,拟定分级—造粒—干燥工艺对氮化钒粉末进行处理,干燥工艺是很重要的工序。分析干燥温度、原料粒径、初含水率以及粘合剂配比对氮化钒生球干燥过程的影响,并探讨生球干燥过程,发现干燥速度与时间的关系曲线呈"单峰"状和"双峰"状,分析这种现象的原因。     

Optimum active and inert ratios for different metamorphic grade coals

In order to quantitatively describe the difference of optimum active and inert ratio of various metamorphic grade coking coals,the rule of coke micro-strength index (MSI),determinated by adding different proportions of inert content to ten kinds of single coal,changing with active and inert ratio has been investigated.Three kinds of change rule of the MSI of ten kinds of single coal changing with active and inert ratio have been obtained in the research.It has been demonstrated that Gauss curve model is the optimal model to describe the optimum active and inert ratio of different metamorphic grade coals.On this basis,the optimum active and inert ratio of different metamorphic grade coals can be given.     

体育照明中金属卤化物灯用电源装置（SPS）的技术要求

本文给出了体育照明中金卤灯用电源装置（SPS）的技术要求，解释和说明技术要求的原因，指出SPS的选用要点。     

Error evaluation on experimental stress–strain curve obtained from tube bulging test

To get precise material data for advanced numerical modelling of tube hydroforming process, the tube bulging test is recommended. Stresses and strains in the tube cannot be evaluated easily and several approaches have been proposed. A review is proposed and points out their advantages and drawbacks.