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101.
Side-chain optimized poly (2,6-dimethyl-1,4-phenylene oxide)-g-poly (styrene sulfonic acid) (PPO-g-PSSA) is designed with balanced water-resistance and sulfonation degree. The PPO-g-PSSA is synthesized by controlled atom-transfer radical polymerization (ATRP) from brominated poly (2,6-dimethyl-1,4-phenylene oxide) (PPO-xBr) and ethyl styrene-4-sulfonate and followed by hydrolysis. A series of PPO-g-PSSA are prepared possessing different bromination degree (x) of PPO-xBr and polymerization degree (m) of the side-chains and the water-resistances of the fabricated membranes are investigated. The results show that a PPO-g-PSSA at relatively low x (x < 0.2) and high m (m > 4) exhibits good balance between the water-resistance and the sulfonation degree. Namely, it displays suitable proton conductivity with compromised water-resistance. Moreover, a maximum ion exchange capacity (IEC) of 3.24 mmol g?1 is reached without the sacrifice of water-resistance. In addition, PPO-g-0.08PSSA-13 and PPO-g-0.14PSSA-4 are chosen characterized by thermogravimetric analysis, proton conductivities and mechanical properties. At 90% RH, the optimized PPO-g-0.08PPSA-13 possesses a proton conductivity of 37.9 mS cm?1 at 40 °C and 45.5 mS cm?1 at 95 °C, respectively.  相似文献   
102.
In this study, design and performance analysis is carried out for a 10 kWh metal hydride based hydrogen storage system. The system is equipped with distinctive aluminium hexagonal honeycomb based heat transfer enhancements (HTE) having higher surface area to volume ratio for effective heat transfer combined with low system weight addition. The system performance was studied under different operating conditions. The optimum absorption condition was achieved at 35 bar with water at room temperature as heat transfer fluid where up to 90% absorption was completed in 7200 s. The performance of the reactor was observed to significantly improve upon the addition of the HTE network at a minimal system weight penalty.  相似文献   
103.
Designing wholesale electricity spot markets even after three decades of experience in dozens of countries continues to be a challenging task. The challenges arise from a myriad of options that exist without adequate level of unbiased guidance, and experiences in real-life markets where successes and failures are also open to the interpretation of experts. This is particularly a critical issue in the developing world where wholesale spot markets are yet to be established in 80 % of the countries and the experience in the remaining 20 % countries with an operational market, is mixed. There are certain trends in selection of market design that leave significant room for improvement including fallacies that should be avoided. Implementation of markets have also been problematic in most cases including unrealistic timetable and inadequate consideration of transition mechanism that have also hampered market development. In this article, we present our views on how policy makers, stakeholders and development institutions should think about the choices around market design and some of the common pitfalls around its implementation.  相似文献   
104.
Ambient fine particulate matter (PM2.5), as one of the predominant air pollutants, has achieved effective control in recent years in China. Whether the use of indoor air purifiers is still necessary needs further exploration. A randomized crossover trial was conducted in 54 healthy students in Beijing, China. Participants were randomized assigned to the use of real or sham high-efficiency particulate air filter (HEPA) for a week and changed the status after a washout period. Health measurements of cardiorespiratory biomarkers were performed at the end of each period. Linear mixed-effects models were used to evaluate the association between PM2.5 exposure and cardiorespiratory biomarkers. Compared with sham air purification, average diastolic blood pressure (DBP), fractional exhaled nitric oxide (FeNO), and 8-isoprostane (8-isoPGF2α) levels decreased significantly in the real purification. The effects of indoor air purification on lung function indicators including forced expiratory volume in one second (FEV1), peak expiratory flow (PEF), and forced expiratory flow between the 25th and 75th percentile of forced vital capacity (FEF25%–75%) were also significant. Our findings showed a protective effect of indoor HEPA air purifiers on cardiorespiratory health of young healthy adults reflected by the decreased blood pressure, respiratory inflammation, and systematic oxidative stress and improved lung function.  相似文献   
105.
ABSTRACT

This paper investigates the role of design in making firms eco-innovate. Going beyond the ‘packed’ approach of environmental studies about ‘eco-design’, we maintain that the eco-innovative impact of design is correlated with the firm’s decision to invest in it. In turn, design investment is assumed connected with the use firms make of design. By pooling the Eurobarometer 2015 and 2016 surveys, we test for these arguments with respect to a sample of nearly 4500 European and non-European (US and Switzerland) manufacturing firms. Results confirm that the firms’ capacity of eco-innovating increases when they invest in design, also by making this investment dependent on the role of design within the firm. The relationship between eco-innovation and design appears robust with respect to the different kinds of ‘eco-innovators’ that the Eurobarometer enables us to consider, while some interesting variability emerges when splitting the sample by group of countries and industries.  相似文献   
106.
Event sequences and time series are widely recorded in many application domains; examples are stock market prices, electronic health records, server operation and performance logs. Common goals for recording are monitoring, root cause analysis and predictive analytics. Current analysis methods generally focus on the exploration of either event sequences or time series. However, deeper insights are gained by combining both. We present a visual analytics approach where users can explore both time series and event data simultaneously, combining visualization, automated methods and human interaction. We enable users to iteratively refine the visualization. Correlations between event sequences and time series can be found by means of an interactive algorithm, which also computes the presence of monotonic effects. We illustrate the effectiveness of our method by applying it to real world and synthetic data sets.  相似文献   
107.
文章研发了一款适用于机器人教育教学的多功能、多用途、普适性的19自由度的小型仿人机器人,主要完成了该机器人的机械结构设计与控制系统构建工作[1]。所设计的机器人机械结构可靠性高、工艺性好、结构紧凑、样式新颖;所构建的机器人控制系统鲁棒性高、稳定性好、控制准确、反应迅速,圆满地实现了预期的设计任务。通过对优缺点的综合对比,得出组合式构型方案在功能性、实用性和稳定性等方面具有明显优势,有望通过后续软件系统的开发提高其运动效能,真正在青少年机器人教育中发挥重要作用[2]。  相似文献   
108.
Package design influences consumers’ expectations of a product’s sensory properties and expected healthiness and/or tastiness, and potentially also changes actual product perception during consumption. The robustness of these effects is far from clear, however. This study investigated the influence of package cues signalling either hedonic or healthy product properties on expectations and subsequent product evaluation over repeated consumption.In a between-subjects design, 92 participants evaluated product expectations and taste perceptions of a chocolate-sesame flavoured biscuit with a package emphasizing either its healthy (n = 44) or hedonic (n = 48) aspects, both at a central location (CLT) and during six home use tests (HUT), using both explicit (questionnaires) and implicit (IAT) measures.Package design significantly affected (p < 0.05) consumers’ expectations of the product. They expected the biscuit to be tastier, less attractive and less healthy in the hedonic package condition, and less tasty, more attractive and healthier in the healthy package condition. However, these effects did not transfer to actual product evaluations upon tasting, either blind or tasting in combination with viewing the package during the HUTs. Implicit attitudes did change as a result of repeated exposures, depending on the package consumers were provided with, indicating product-package interactions over time (p < 0.05).In conclusion, package design influences product expectations and associations with its healthiness and attractiveness, which is of relevance in product choice and purchase settings. However, at the stage of (repeated) consumption, intrinsic (sensory) properties become the dominant drivers of products’ sensory and hedonic evaluations, and the impact of package cues seems less potent.  相似文献   
109.
Brick masonry is not only a question of building physics, building construction and durability, i.e. sustainability, but has much to do with aesthetics and making sense, which may have been forgotten in modern architecture with its absolute lack of décor. Masonry as an art form has been scarce since the era of brick expressionism. Recently, there have been some exceptions – and thoroughly welcome. The ”Fjordenhus“ in Vejle, Denmark, is an astonishing example.  相似文献   
110.
Histone deacetylase inhibitors (HDACIs) are responsible for controlling gene expression by modulating the acetylation status of histone proteins. Furthermore, they modulate the activity of cytoplasmic non-histone proteins. Due to the involvement of HDACs in neurodevelopment, memory formation, and cognitive processes, HDACIs have been suggested as innovative agents for the treatment of neurodegenerative disorders such as Alzheimer's disease (AD). Given their mechanisms of action and the complex nature of AD, HDACIs have been proposed for the design of novel multitarget ligands (MTLs). To this aim, the fragment responsible for HDAC inhibition has been coupled with other structures that are able to provide additional biological actions, such as antioxidant activity or the inhibition of phosphodiesterase 5, transglutaminase 2, and glycogen synthase kinase 3β. Herein we discuss recent efforts to design HDACI-based MTLs as potential disease-modifying entities.  相似文献   
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