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11.
The development of a sustainable energy system throughout an enterprise is a complex task, which requires an agile holistic approach. Such an approach needs to include a variety of objectives including energy strategy formation and strategic decision-making, which are directly related to the analysis and management of the main areas of sustainable development:The economic, technological, environmental, and social. These multidimensional requirements of sustainability are often difficult to achieve within the enterprise, because these aspects are interrelated and influenced by various internal and external environment factors. This paper first reviews the main challenges for an energy system, and then demonstrates how a strategic agile enterprise architecture driven approach could effectively guide the sustainable energy system development. The study presented in this paper provides a holistic approach that contributes to the advancement and usage of literature dealing with issues of sustainable energy system development and agile enterprise architecture, which has not been discussed before to any great extent. 相似文献
12.
Novel organic dyes containing N-bridged oligothiophene coplanar cores for dye-sensitized solar cells
Three novel organic dyes adopting fully-fused coplanar heteroarene as the donor moieties end-capped with two cyanoacrylic acids as acceptors and anchoring groups have been synthesized, characterized, and used as the sensitizers for dye-sensitized solar cells (DSSCs). The photophysical and electrochemical properties of the novel dyes and the characteristics of the DSSCs based on the novel organic dyes were investigated. The incorporation of the coplanar cores with electron-donating N-bridges are beneficial for the better intramolecular charge transfer (ICT), giving these new dyes good light-harvesting capability. The LUMO energy levels of these coplanar heteroacene-based dyes are sufficiently high for the efficient electron injection to TiO2 upon photo-excitation, while the suitable HOMOs allow the regeneration of oxidized dyes with the electrolyte redox (I−/I3−). The structural features of the coplanar cores (penta vs. hexa heteroarene) as well as the alkyl substitutions play crucial roles in governing the physical properties and device performance. Among these three novel organic sensitizers, the EHTt dye composed of a fully fused hexa-arene core and less bulky N-alkyl groups caused the DSSC to show the best photovoltaic performance with an open-circuit voltage (VOC) of 0.58 V, a short-circuit photocurrent density (JSC) of 13.72 mA/cm2, and a fill factor (FF) of 0.69, yielding an overall power conversion efficiency (PCE) of 5.52% under AM 1.5G solar irradiation. 相似文献
13.
As a symbol of sharing economy, ride-hailing services have spread to Asia, where various forms of services have been established according to the existing socio-technical regimes, including legal, policy, and environmental concerns. China, in particular, has accepted ride-hailing services by revising existing institutions. This study analyzes China’s acceptance of ride-hailing services in the socio-technical system context set up for legacy services. Simulation modeling, combined with transition theory and an agent-based model, is used to analyze the data. This study calculates consumer disutility based on mobility market share, reflecting consumer preference, and predicts the sustainability of ride-hailing services. The simulation results conclude that legalization and socio-technical context are of importance for sustainable mobility. 相似文献
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蛋白质-多糖复合体系作为生物活性物质传递系统的壁材,有着人工合成聚合物或无机物等其他材料不可比拟的多重优势。本文就蛋白质和多糖之间的连接方式及蛋白质-多糖复合体系形成传递系统的多种形式进行了综述,以及对此领域的发展趋势进行了展望。结合蛋白质和多糖的结构特点,二者之间的链接方式分为非共价结合的物理共聚,和共价结合的美拉德偶联、化学交联、酶催化交联等方式,文中分别对各种连接方式的原理和机理,以及其影响因素做了深入阐述。以蛋白质-多糖复合体系为壁材对活性物质的传递形式大体上分成乳化系统、胶束、纳米凝胶、分子复合物以及壳核结构等系统。不同的活性物质的特征和传递需求,可针对性地选择合适结构的蛋白质和多糖种类以及二者的连接方式和传递系统的形式。并且,随着研究的逐步发展和推进,此领域的发展趋势朝着智能化和靶向性的方向进行。目前活性物质的蛋白质-多糖复合体系的传递系统,还依然面临着系统设计、评价和应用等多方面的挑战,这就要求我们在更全面更深入了解认识其对活性物质影响和功效的基础上,安全合理地设计和深入细致地评价活性成分的传递系统。 相似文献
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An oriented tetrahedron defined on four vertices is a set of four cyclic triples with the property that any ordered pair of vertices is contained in exactly one of the cyclic triples. A tetrahedral quadruple system of order with index , denoted by , is a pair , where is an ‐set and is a set of oriented tetrahedra (blocks) such that every cyclic triple on is contained in exactly members of . A is pure if there do not exist two blocks with the same vertex set. When , the spectrum of a pure TQS has been completely determined by Ji. In this paper, we show that there exists a pure if and only if and . A corollary is that a simple also exists if and only if and . 相似文献
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19.
Leonor Contreras Ignacio Villarroel Camila Torres Roberto Rozas 《Molecules (Basel, Switzerland)》2021,26(6)
Doxorubicin (DOX), a recognized anticancer drug, forms stable associations with carbon nanotubes (CNTs). CNTs when properly functionalized have the ability to anchor directly in cancerous tumors where the release of the drug occurs thanks to the tumor slightly acidic pH. Herein, we study the armchair and zigzag CNTs with Stone–Wales (SW) defects to rank their ability to encapsulate DOX by determining the DOX-CNT binding free energies using the MM/PBSA and MM/GBSA methods implemented in AMBER16. We investigate also the chiral CNTs with haeckelite defects. Each haeckelite defect consists of a pair of square and octagonal rings. The armchair and zigzag CNT with SW defects and chiral nanotubes with haeckelite defects predict DOX-CNT interactions that depend on the length of the nanotube, the number of present defects and nitrogen doping. Chiral nanotubes having two haeckelite defects reveal a clear dependence on the nitrogen content with DOX-CNT interaction forces decreasing in the order 0N > 4N > 8N. These results contribute to a further understanding of drug-nanotube interactions and to the design of new drug delivery systems based on CNTs. 相似文献
20.
心理测试的根本目的是为了让人们在测试过程中,产生某些特定行为,即个体对测试题目的反应,并根据这些行为反应来推论其相应的心理特性。在一定程度上帮助我们了解人类的心理活动,并从中得到帮助。因此,本文对基于学生群体心理测试系统的设计进行深入研究。 相似文献