Soot oxidation kinetics under pressurized conditions

The oxidation kinetics, under different pressures, of soot samples obtained from different liquid fuels and two standards (a commercial black carbon sample and a reference diesel soot) was studied. Soot samples were generated in a flat-flame, premixed burner under heavily-sooting conditions and captured on a water-cooled stabilization plate located above the burner surface. The collected soot was oxidized using a high-pressure thermogravimetric analyzer (HTGA). TGA operation was optimized to reduce mass transfer effects by adjusting the oxidizer flow rate and initial sample mass. Further corrections for mass transfer were accomplished by computing the effectiveness factors for intraparticle, interparticle, and external mass transfer. Two pressures were evaluated (1 and 10 atm) and O₂ concentration was varied between 10 and 21%.     

The potential of public participation to facilitate infrastructure decision-making: Lessons from the German and European legal planning system for electricity grid expansion

The article examines the potential role that public engagement and participative pro-cesses to play a role in effective infrastructure planning in the context of energy policies. For example, by 2050, at least 80% of Germany’s electricity has to be derived from re-newable energy sources if Germany is to meet the goals of its own energy policy. This includes the comprehensive and accelerated extension of the electricity grid. As a result of the magnitude of these changes, the German energy transition is not proceeding without debate and controversy. Public engagement is certainly no panacea for en-hanced social acceptance, yet it offers substantial potential to facilitate the energy tran-sition. The paper draws together social science and legal expertise in order to investi-gate the role of public participation in legal planning processes concerning energy infra-structures. The paper not only focuses on the extension of the German power grid, but also deals with participative policy at the European level. To this end, the paper analyzes the potential role of the German legal planning system in grid expansion and in the Eu-ropean processes of nominating Projects of Common Interest (PCI) and of drawing up the Ten Year Network Development Plan (TYNDP).     

From dynamic capabilities to ERP enabled business improvements: The mediating effect of the implementation project

This study explores whether an Enterprise Resource Planning (ERP) implementation project mediates the relationship between dynamic pre-adoption capabilities and ERP-enabled business improvements. The results from our field survey of large ERP adopters in Austria suggest that the effects of the two out of three selected dynamic capabilities are dependent on the properties of the underlying organizational transformation project. While external information acquisition and IT governance capabilities are fully mediated by the performance of the ERP implementation project, decision making only directly impacts business capabilities. These results further our understanding about the role of the implementation project for ERP value creation and the different natures of capability relationships. We call for more research on co-presence conditions related to dynamic capabilities and IT transformation project performance.     

2014年第一季度中国反垃圾邮件状况调查报告

首先介绍了2014年第一季度电子邮箱用户使用电子邮箱情况,然后分析了电子邮件的垃圾邮件状况及用户对垃圾邮件的处理方式,最后提出了垃圾邮件问题与治理的新形势.     

Soot formation in high pressure laminar diffusion flames

The details of the chemical and physical mechanisms of the soot formation process in combustion remain uncertain due to the highly complex nature of hydrocarbon flames, and only a few principles are firmly established mostly for atmospheric conditions. In spite of the fact that most combustion devices used for transportation operate at very high pressures (e.g., aircraft gas turbines up to 40 atm, diesel engines exceeding 100 atm), our understanding of soot formation at these pressures is not at a desirable level, and there is a fundamental lack of experimental data and complementary predictive models. The focus of this review is to assess the experimental results available from laminar co-flow diffusion flames burning at elevated pressures. First, a brief review of soot formation mechanisms in diffusion flames is presented. This is followed by an assessment of soot diagnostics techniques, both intrusive and non-intrusive, most commonly used in soot experiments including the laser induced incandescence. Then the experimental results of soot measurements done at elevated pressures in diffusion flames are reviewed and critically assessed. Soot studies in shock tubes and in premixed flames are not covered. Smoke point fuel mass flow rate is revisited, and shortcomings in recent measurements are pointed. The basic requirements for tractable and comparable measurements as a function of pressure are summarized. Most recent studies at high pressures with aliphatic gaseous fuels show that the soot yield displays a unified behaviour with reduced pressure. The maximum soot yield seems to reach a plateau asymptotically as the pressure exceeds the critical pressure of the fuel. Lack of experimental data on the sensitivity of soot morphology to pressure is emphasized. A short summary of efforts in the literature on the numerical simulation of soot formation in diffusion flames at high pressures is the last section of the paper.     

Exploring the roles of portfolio steering committees in project portfolio governance

Governing project portfolios engages different actors in organizations including portfolio managers, portfolio officers, top managers, and others who may team up as portfolio steering committees. While portfolio steering committees play a regular role in project portfolio governance, their role is still unclear. Through an in-depth multiple case study in three Danish companies, the roles of portfolio steering committees were explored. The results showed that portfolio committees may play three distinct roles in portfolio governance: a) communication and consolidation role, b) negotiation role, and c) decision making role. The results challenged the notion that portfolio committee meetings are the place and time to make collective decisions on the portfolio, rather, portfolio steering committees might unintentionally become or intentionally be used for other purposes than decision making. The empirical evidence of the study proposes that these three roles might be related to two governance design factors: frequency and duration of committee meetings.     

我国煤炭资源下火电厂的环境效益分析

当今社会,节能、减排、环保已成为中国未来的经济发展必须考虑的重要因素。文章分析了我国不同发电机组的的空气污染排放量,并与国家标准相比,可知在我国某些省份存在大量老旧机组,能耗高,污染重,使空气污染物排放不能达到令人满意,由此给出了减少空气污染物排放的合理建议。     

发展型政府与大规模城镇开发的治理——“两次价值循环”理论的提出

政府驱动大规模城镇开发是我国地区发展的常见模式,曾发挥重要作用,但目前正面临重大转型。本文结合从计划经济与改革开放的实践纵览与宁波北仑地区开发案例的分析,对"发展型政府"推动大规模开发的内在逻辑作出解释。研究认为:政府驱动大规模城镇开发这一常见模式,并不仅仅是政府推动的结果,而是一个政府与市场携手于地区开发的"两次价值循环"过程。其中,"项目价值循环"和"价值大循环"的两层次结构让"集中"与"分散"两类制度的力量得以互动共生,这是我国政府推动大规模城镇开发取得成绩的关键逻辑;但同时,这种结构也带来了两类主体相互杂糅的逻辑悖论和现实问题,对此,通过区分两次价值循环、建构"政府"与"市场"相协作的新型联合开发机制,可以实现一定程度的改进。     

Choosing Confrontation or Consensus in the Inner City: Lessons from a Community-University Partnership

This article describes the experiences of a Los Angeles inner-city neighbourhood in its attempt for revitalization. The authors headed a Community-University Partnership and worked with graduate students to offer technical support to a neighbourhood-based coalition. The students, local residents, merchants and neighbourhood institutions attempted to follow an asset-based consensus building approach to community development. The article describes the different components of their strategy for physical, economic, cultural and social revitalization, and analyzes the lessons learned from the successes and setbacks of this effort. Finally, the authors discuss some apparent limitations of the asset-based consensus approach.