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关键词： Entropy   Ornstein-Weiss lemma   Bowen formula   Uniform space   Dynamical system   Cut and project scheme   Amenable group   Van Hove sequence   Folner sequence   Uniform lattice  

摘要： In the study of aperiodic order via dynamical methods, topological entropy is an important concept. In this paper, parts of the theory, like Bowen's formula for fibre wise entropy or the independence of the definition from the choice of a Van Hove sequence, are extended to actions of several non-discrete groups. To establish these results, we will show that the Ornstein-Weiss lemma is valid for all considered groups which appear in the study of cut and project schemes.

关键词： Karst groundwater system   Tunnel construction   Drawdown   Discharge   Area of impact  

摘要： Anthropogenic disturbance of karst groundwater systems by large-scale underground engineering activities is an important topic but is difficult to address due to the compound influence of the heterogeneity and construction progression. In this study, we adopt the coupled discrete-continuum modeling approach where both the tunnels and karst conduits are treated as discrete channels. Based on extensive site characterization, groundwater observations, and tunnel discharge data, we establish a three-dimensional coupled model for a karst aquifer where deeply-buried, long tunnels are being constructed. We perform high-resolution simulations to quantitatively evaluate the spatial and temporal characteristics of the tunnel construction impact on a karst groundwater system. The simulation results satisfactorily reproduce the tunnel discharge time-series. We show that the excavation and lining schedule is an important factor to consider when evaluating the hydrogeological impact. During tunnel construction, the groundwater drainage through the tunnels (5.3 x 10(7) m(3)) accounts for a significant part of the total groundwater discharge (similar to 11%) in the studied area. The continuous water influx to the tunnels results in widespread drawdown with an area of impact (with drawdown >5 m) covering 64.0% of the entire study area after four years of construction. The total discharge through karst conduits decreases by about 30% in response to the tunnel construction. Our simulation results predict that after completion of lining the groundwater system will slowly approach a groundwater level 5-10 m below the undisturbed level. This work demonstrates the use of coupled discrete-continuum models to study regional groundwater flow in karst aquifers affected by tunnel engineering activities and also provides a guidance for the impact assessment of other underground engineering projects in mining and transportation industries. The simulation methodology may be exploited for optimiza

关键词： Surface defect engineering   Fe doping   Bi7O9I3   Charge-carrier separation   Molecular oxygen activation  

摘要： Effective charge-carrier separation and molecular oxygen activation are crucial factors for photocatalytic environmental purification. Herein, an efficient Fe-doped Bi7O9I3 microflowers photocatalyst was synthesized. It was discovered that Fe doping could not only tune the concentration of oxygen vacancies of Bi7O9I3 to optimize the dissociation of excitons, but also promote the separation of charge-carriers and the activation of oxygen molecules. Meanwhile, the inducing of surface oxygen vacancies and Fe3+/Fe2+ by Fe optimal doping can act as the activation center for catalytic reactions, which also significantly enhances the photocatalytic activity. Benefiting from the optimized properties, the photocatalytic activity of Fe-doped Bi7O9I3 photocatalyst has been significantly improved by more than 4 times. Finally, we proposed that a highly efficient catalytic oxidation reaction mechanism can be achieved via modulating Fe doping to induce oxygen vacancies to promote charge separation and molecular oxygen activation. This work provides a novel approach for designing efficient photocatalysts.

关键词： C2H6   C2H4 separation   carboxylic acids   metal–   organic frameworks   nanostructures   materials chemistry  

摘要： Herein, a dynamic spacer installation (DSI) strategy has been implemented to construct a series of multifunctional metal-organic frameworks (MOFs), LIFM-61/31/62/63, with optimized pore space and pore environment for ethane/ethylene separation. In this respect, a series of linear dicarboxylic acids were deliberately installed in the prototype MOF, LIFM-28, leading to a dramatically increased pore volume (from 0.41 to 0.82 cm(3) g(-1)) and reduced pore size (from 11.1x11.1 angstrom(2) to 5.6x5.6 angstrom(2)). The increased pore volume endows the multifunctional MOFs with much higher ethane adsorption capacity, especially for LIFM-63 (4.8 mmol g(-1)), representing nearly three times as much ethane as the prototypical counterpart (1.7 mmol g(-1)) at 273 K and 1 bar. Meanwhile, the reduced pore size imparts enhanced ethane/ethylene selectivity of the multifunctional MOFs. Theoretical calculations and dynamic breakthrough experiments confirm that the DSI is a promising approach for the rational design of multifunctional MOFs for this challenging task.

关键词： 制药工程   制药技术   分离技术  

摘要： 药品研发作为民生事业发展的基础,直接关系到各种疾病的治愈效果。从近年来医药产业在经济市场中的地位来看,亚健康、环境恶化、病毒等引发的疾病极大地扩大了医药产业的发展规模。为了提高药品的功能属性,应采用合理的制药工艺,使药品具有较大的实用价值,从而提高药品质量,满足使用者的需求。

关键词： 膜分离技术   生态修复   应用实例  

摘要： 文章介绍了膜分离技术在生态修复中应用实例,其中包括滨海盐碱地改良及淋洗水脱盐工程、储备生态林建设中浇灌用水不达标水处理工程、地热水回灌膜法处理工程、膜法海水淡化在海岛修复中应用,分析了膜分离技术处理效果和技术优势,为后续生态修复用水提供参考。

关键词： 高校课堂   教学模式   混合式教学   “生物分离工程”  

摘要： 疫情期间,各类教学平台和手段的应用、课堂教学模式的改变,推动了课程教学从"教"到"学"为中心的转变。基于疫情期间经验,构建提升学生自主学习能力的混合教学模式,并运用于"生物分离工程"课程的课堂教学,明显提升了学生的自学能力和教学效果。

关键词： 课程思政   工程伦理   分离过程   课程改革  

摘要： 工程伦理教育属于思想政治教育的范畴,旨在培育作为未来工程师的工科大学生的良好工程价值观.《化工分离过程》作为化工专业的一门专业核心课程,在课程教学中深入贯彻课程思政理念,加强工程伦理教育认识,改进工程伦理教育方式.教学过程中通过小组设计、工程案例分析、网络资源利用等方式将工程伦理思政元素与专业知识融合,是专业课程改革的重要方式,也是加强学生思政教育的必由之路.

关键词： 评标委员会   咨询建议   投标文件   门源回族自治县   海北藏族自治州   工程招投标   招标人   房屋建筑  

摘要： 青海省住房和城乡建设厅4月10日起,将在海北藏族自治州门源回族自治县房屋建筑和市政基础设施工程招投标中开展“评定分离”试点工作。“评定分离”是指评标委员会对投标文件的技术、质量、安全、工期的控制能力等因素提供技术咨询建议,向招标人推荐合格的中标候选人。由招标人按照科学、民主决策原则,根据报价情况和技术咨询建议,择优确定中标人。

关键词： 专业学位   高等分离工程   对分课堂   探索式  

摘要： 概述了课程概要及教学改革必要性,分析了适应专业学位教育方向,与企业共进课堂,并详细论述了教学内容安排及教学重点,探讨引入“以学生为中心”的课程理念及对分课堂的教学手段,以及绿色、生态化工理念。以强化学生的主动学习能力和创新能力。