Hydrogen production from sucrose via aqueous-phase reforming

Commercial sucrose was used to produce hydrogen in a combined approach of hydrogenation and aqueous phase reforming (APR). First a mixture of technical sorbitol/mannitol was produced by hydrogenating an aqueous solution of sucrose in a trickle bed reactor over 5 wt % Ru/C. The produced polyols were treated in a continuous reactor at 498 K and elevated pressure deploying a 2.5 wt % Pt/C catalyst to yield hydrogen. The highest hydrogen selectivity was 62%. No large differences were found when comparing a commercial available sorbitol to the technical sorbitol/mannitol mixture in terms of conversion levels and selectivity to the gas-phase products. This was accompanied by a similar distribution of products retained in the liquid phase. The efficiency of APR when utilizing Pt/C was found to be still insufficient for industrial implementation in terms of hydrogen production. Thus, additional efforts should be made to increase the obtained amounts of hydrogen per mole of converted sugar alcohols.     

A thorough investigation for development of hydrogen projects from wind energy: A case study

Increasing energy demand has led to a substantial growth in the use of wind energy across the world, which can be attributed to the low initial and running costs and rapid and easy deployment of this technology. The development of hydrogen from wind energy is an excellent way to store the excess wind power produced, as the produced hydrogen can be used not only as clean fuel but also as input for various industries. Considering the good wind potentials of Yazd province, the variety of industries that are active in this area, and the central location of this province in Iran, which gives it ample access to major transport routes and other industrial hubs, hydrogen production from wind power in this province could benefit not only this region but the entire country. Given these considerations, we conducted a technical, economic, and environmental assessment of the potential for wind power generation and hydrogen production in Yazd province. Overall, the assessments showed that the best locations for harvesting wind energy in this province are Bahabad and Halvan stations. For these two stations, it is recommended to use EWT DW 52-900 turbine to take advantage of its higher nominal capacity to achieve higher electricity and hydrogen output and emission reduction. For Abarkoh and Kerit stations, which have a low wind energy potential, it is recommended to use small turbines such as Eovent EVA120 H-Darrieus. Also, economic and technical assessments showed that it is not economically justified to harvest wind energy in Ardakan station. The results of ranking the stations with the Step-wise Weight Assessment Ratio Analysis (SWARA) and Evaluation based on Distance from Average Solution (EDAS) techniques showed that Bahabad station was introduced as the best place to produce hydrogen from wind energy.     

Service quality,technical efficiency and total factor productivity growth in Pakistan's post-reform electricity distribution companies

Pakistan's energy sector has undergone substantial reforms during the last three decades with the aim to improve its operational performance and to cater to the growing energy needs of the economy. In the wake of these reforms, the WAPDA Act was passed in 1998 to achieve operational and financial efficiencies. Pakistan's electricity market is still hampered by issues like extended blackouts, electricity thefts, high circular debt and poor service quality. The electricity distribution sector is thus an interesting case to investigate its efficiency in the post-reform period by examining the impact of service-quality parameters (SQPs), which have generally been neglected in the literature. Stochastic frontier analysis has been used to estimate technical efficiency, while the Malmquist Productivity Index is implemented to decompose total factor productivity (TFP) into scale change, technical change and efficiency change from 2006 to 2016. We conclude that the technical efficiency score declines from 98 percent to 36 percent with the inclusion of SQPs in the models. The results also indicate a negative trend in scale change, implying that distribution companies are not operating at the technically optimal scale. We propose that the regulatory body should change its governance regime and focus on incentive-based regulation instead of rate-of-return regulation.     

The effects of environmental regulation and technical progress on CO2 Kuznets curve: An evidence from China

Based on environmental Kuznets curve theory, a panel data model which takes environmental regulation and technical progress as its moderating factors was developed to analyse the institutional and technical factors that affect the path of low-carbon economic development. The results indicated that there was a CO₂ emission Kuznets curve seen in China. Environmental regulation had a significant moderating effect on the curve, and the inflection of CO₂ emissions could come substantially earlier under stricter environmental regulation. Meanwhile, the impact of technical progress on the low-carbon economic development path had a longer hysteresis effect but restrained CO₂ emission during its increasing stage and accelerated its downward trend during the decreasing stage which was conducive to emission reduction. Strict environmental regulation could force the high-carbon emitting industries to transfer from the eastern regions to the central or the western regions of China, which would make the CO₂ Kuznets curve higher in its increasing stage and lower in its decreasing stage than that under looser regulation. Furthermore, energy efficiency, energy structure, and industrial structure exerted a significant direct impact on CO₂ emissions; we should consider the above factors as essential in the quest for low-carbon economic development.     

浅谈线路调试中的现代手段

信息时代的到来推动了我国电子产业的发展，电子产品的发展必将离不开线路调试工作，电路的调试在实际的运行中占据着十分重要的地位。一般情况下电子电路的调试需要达到预定的指标，而每一部分都需要拥有详细而有序的电路调试方式。本文笔者将会针对线路调试的准备工作进行简单的分析，并对电源调试和调试方法及步骤等内容进行具体的阐述。     

工业企业变电站执行防火技术规范问题探讨

对工业企业变电站防火工作中执行防火技术规范遇到的不同规范之间规定不一致的问题进行分析。在此基础上探讨解决这些问题的方法。     

Integration framework for simulations and SCADA systems

Stricter requirements on the quality of industrial plant operation together with environmental limits and decreasing energy consumption bring more complex automation systems. The intelligent control techniques, which are based on approaches from diverse disciplines including statistics, artificial intelligence or signal processing, have been widely used during the last years and their benefits have been proved. They cannot be developed and tested without simulation models and access to online and historical data. This article proposes a platform for the integration of simulations and industrial SCADA systems supporting complex data access and simulation code re-use.The idea of the presented framework is to connect simulations, data sources, optimizers, other calculations and SCADA systems into one integrated environment seamlessly. A technical level of the framework provides integration of stakeholders and a semantic level captures engineering knowledge in inter-mapped ontologies and configures the technical level, which is often called model-driven configuration. The semantic level utilizes a formal model implemented as set of ontologies. The major contribution of the article are the layered model of the integration architecture and formulation of the integration requirements in the industrial automation domain. The proposed solution has been implemented and tested on a software prototype level. It is demonstrated on two use-cases covering both design and integration of simulation models from the industrial perspective. The proposed architecture is intended to be as general as possible, however it has been tested on signal-oriented simulators only. It is the main limitation of this contribution and it should be addressed in upcoming work.     

双向拉伸聚酯薄膜生产线的技术创新

综述了国内外双向拉伸聚酯薄膜(BOPET)生产线技术水平的差异。并在现有的生产线配套系统上,进行了技术改进和创新,并取得了较好的效果。     

理县甘堡藏寨灾后重建的几点思考

聚居于川西高山峡谷地区的藏羌民族,处于历史上多民族文化互相冲撞又互相整合的＂藏彝走廊＂地区。特殊的地理位置及历史上的民族交融,使其民居聚落与民居建筑强烈地表现出其民族地域属性,成为独具特色的地域建筑文化景观。＂5.12＂地震之后的灾后重建中,如何传承当地独特的地域建筑景观是人们普遍关注的问题,本文以理县甘堡藏寨重建案例入手,站在地区建筑学的立场上进行反思,试图阐释尊重文脉,尊重本土精神,尊重民族习俗的方法和通道,期望对于我们今后的民族村落建设有所裨益。     

Developing a tendering strategy in two-envelope fee tendering based on technical score-fee variability

Consultants, in competing for work through two-envelope fee tendering, have been urged to consider variability differences between fees and technical scores, since the criterion with the greatest variability will influence which consultant is awarded the contract. Fee and technical score variability arising from different client fee tendering competitions is analysed in this paper, and a method proposed for determining whether a particular client's two-envelope fee tendering competition is likely to be dominated in terms of technical score or fee. Such information should be useful to consultants, as part of their bidding strategy, in deciding whether to aim for a higher technical score or submit a lower fee. Standard deviation is used to measure fee and technical score variability. Fee and technical score standard deviations are determined for each tendering competition, expressed as a ratio and aggregated over a series of competitions. A technical score-fee standard deviation ratio approximately equal to unity indicates that for future competitions consultants should adopt a balanced bidding strategy in putting equal emphasis on fee and technical score. A smaller ratio indicates that consultants should adopt a ‘low fee’ strategy whereas a larger ratio shows that consultants should adopt a ‘high technical score’ strategy. Fee tendering data from two large Hong Kong public sector clients were analysed. Fees were found to dominate the vast majority of tendering competitions, thereby indicating that consultants would be wise to adopt a low fee strategy in future competitions.