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181.
Traditionally structure–activity/affinity relationships (SAR) have dominated research in medicinal chemistry. However, structure–kinetics relationships (SKR) can be very informative too. In this viewpoint we explore the molecular determinants of binding kinetics and discuss challenges for future binding kinetics studies. A scheme for future kinetics‐directed drug design and discovery is also proposed. 相似文献
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183.
Energy saving is an important option for preventing emission of greenhouse gases. Furthermore, when energy saving is reducing the spatial and temporal density of energy consumption, it supports a rising market share of renewable energy sources. Last but not the least, energy saving plays a role in reducing the vulnerability for import dependency and supply disruptions. Despite these virtues energy saving and energy efficiency, being typically demand side options, appear to be harder to ‘sell’ than the other options which focus on the supply side. The currently prevailing market-based approach in energy policy initially brought setbacks for energy saving. The introductory article and the selected contributions to this special issue intend to show that markets can and should be shaped to the benefit of the uptake and of the potential of energy saving. To this end, all elements of the energy efficiency delivery context should be addressed in energy-saving policies. Learning, measurement and observation are important tools in this reshaping process. All contributions are based on papers of the European Council for an Energy Efficient Economy 2003 Summer Study. 相似文献
184.
Tjitske J. Geertsema Paul J. J. F. Torfs Joris P. C. Eekhout Adriaan J. Teuling Antonius J. F. Hoitink 《河流研究与利用》2020,36(7):1171-1182
Placement of wood in streams has become a common method to increase ecological value in river and stream restoration and is widely used in natural environments. Water managers, however, are often hesitant to introduce wood in channels that drain agricultural and urban areas because of backwater effect concerns. This study aims to better understand the dependence of wood‐induced backwater effects on cross‐sectional area reduction and on discharge variation. A newly developed, one‐dimensional stationary model demonstrates how a reduction in water level over the wood patch significantly increases directly after wood insertion. The water level drop is found to increase with discharge, up to a maximum level. If the discharge increases beyond this maximum, the water level drop reduces to a value that may represent the situation without wood. This reduction predominately depends on the obstruction ratio, calculated as the area covered by wood in the channel cross section divided by the total cross‐sectional area. The model was calibrated with data from a field study in four lowland streams in the Netherlands. The field study showed that morphologic adjustments in the stream and reorientation of the woody material reduced the water level reduction over the patches in time. The backwater effects can thus be reduced by optimizing the location where wood patches are placed and by manipulating the obstruction ratio. The model can function as a generic tool to achieve a stream design with wood that optimizes the hydrological and ecological potential of streams. 相似文献