NO emission characteristics in counterflow diffusion flame of blended fuel of H2/CO2/Ar

Flame structure and NO emission characteristics in counterflow diffusion flame of blended fuel of H₂/CO₂/Ar have been numerically simulated with detailed chemistry. The combination of H₂, CO₂ and Ar as fuel is selected to clearly display the contribution of hydrocarbon products to flame structure and NO emission characteristics due to the breakdown of CO₂. A radiative heat loss term is involved to correctly describe the flame dynamics especially at low strain rates. The detailed chemistry adopts the reaction mechanism of GRI 2.11, which consists of 49 species and 279 elementary reactions. All mechanisms including thermal, NO₂, N₂O and Fenimore are taken into account to separately evaluate the effects of CO₂ addition on NO emission characteristics. The increase of added CO₂ quantity causes flame temperature to fall since at high strain rates a diluent effect is prevailing and at low strain rates the breakdown of CO₂ produces relatively populous hydrocarbon products and thus the existence of hydrocarbon products inhibits chain branching. It is also found that the contribution of NO production by N₂O and NO₂ mechanisms are negligible and that thermal mechanism is concentrated on only the reaction zone. As strain rate and CO₂ quantity increase, NO production is remarkably augmented. Copyright © 2002 John Wiley & Sons, Ltd.     

PowerPoint2000动画设计应用

PowerPoint2000是Microsoft公司办公自动化软件Office2000的重要构件之一。其自身具有强大的处理功能，尤其是PowerPoint2000所提供的基本动画效果，更是给演示文稿增添了很多色彩。如果能将这些基本动画效果巧妙地组合在一起，就会创作出更富感染力的作品。就创作中的技巧并结合应用举例分析如下。相信人们可以利用这些设计思想，创作出更加精彩的作品。     

低品位硼矿的富集加工技术

报道了青海大柴旦地区低品位硼矿富集加工的新工艺，该工艺使硼矿品位30％－35％，B2O3收率大于80％，该工艺路线已工业化。     

Microscopic and Macroscopic Growth Rates of Fatigue Cracks in Steels and Alloys under the Influence of Crack Closure

On the basis of the experimental data, we show that the difference between the macroscopic and microscopic fatigue crack growth rates in the second section of the kinetic diagram of fatigue fracture is caused by the effect of crack closure within the limits of its existence. We establish the relationships between the macroscopic and microscopic fatigue crack growth rates and the structure of the material in the second section of the diagram for various values of the load ratio with regard for the effect of crack closure and propose a procedure of examination of the fracture processes in structural materials based on the analysis of microscopic and macroscopic fatigue crack growth rates.     

FW调剖技术及应用

应用FW调剖技术有针对性地对 119口非钻停井区注水井采取了 4种精细调剖方案 ,对比了化学浅调剖应用前后注水井层间矛盾的缓解 ,纵向上吸水剖面的改善 ,注水量和吸水指数的变化及渗流能力的变化。结果表明 ,注水井化学浅调剖后 ,井区的连通油井明显受效 ,获得较高的增油量 ,水驱的开发效果得到改善。化学浅调剖可以有效地封堵高渗透层 ,扩大低渗透层注入水的波及体积 ,减缓注水井层间矛盾 ,实现了对注水井吸水剖面的有效调整 ,这对深化注水结构调整、挖掘各类油层潜力、提高储量动用程度有显著的效果。     

影响掺矿渣的钢纤维砼强度的主要因素

研究结果表明 :水胶比、胶凝材料用量、钢纤维掺量、矿渣代水泥量对钢纤维砼强度影响显著。当矿渣取代水泥 10 %时 ,钢纤维砼强度最高。经试验选择出一个具有良好和易性和较高强度 (118MPa)的钢纤维砼配合比 ,为掺磨细矿渣的中含量超短异形钢纤维砼的设计和施工提供了试验依据     

Preparation and Application of Active Composite Antibacterial Material Containing Ag~ and Zn~(2 )

1Introduction Harmfulbacteriaexistanywhereintheworldsuchas soil,air,water,surfacesofobjectsandourskins,etc.Thenumberofbacteriumisenormous,withmanydiffer entspecies.Theyhavethreatenedthehealthofhuman beingsseriously.Withthedevelopmentofeconomyand environme…     

轻型钢骨结构低层住宅设计荷载分析

本文讨论了北美低层钢骨结构住宅结构设计的荷载问题，包括各类荷载的取值和计算方法，以及荷载组合模式，并提出了在我国相关规范没有出台前，在国内进行设计时应该注意的一些问题。     

The effects of FG7142 on two types of forgetting in 18-day-old rats.

The authors studied the role of gamma-aminobutyric acid (GABA) in 2 types of forgetting of fear in the developing rat. One type of forgetting studied was that observed after an intermediate retention interval (the "Kamin effect"); the other type studied was that observed after a longer interval (infantile amnesia). Rats were given pairings of an auditory conditioned stimulus with shock, and learned fear was assessed by freezing. Forgetting at an intermediate retention interval (1 hr) was not alleviated by the GABAA receptor partial inverse agonist FG7142 (0, 1, 5, or 10 mg/kg), whereas forgetting at a longer retention interval (48 hr) was alleviated. These results suggest that in the developing rat, forgetting observed at different retention intervals is mediated by different physiological mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Theory of propagating deformation bands

A model for propagating deformation bands is developed, based on a mechanical equation of state and on evolution equations for the structure parameters. It is shown that, contrary to normal deformation, it is necessary to discriminate between global parameters which depend solely on time elapsed and local parameters which are functions of the strain history. Correspondingly, two sets of equations are presented, one describing the development of the global parameters in the course of time, the other giving the evolution of the local state parameters in the course of deformation, i.e. as a function of strain. Measurable quantities derived from the first set are the load serrations and the band velocity, while the second set yields the flow stress and the strain profile of the propagating band.