Economic competitiveness of compact steam methane reforming technology for on-site hydrogen supply: A Foshan case study

On-site hydrogen production through steam-methane reforming (SMR) from city gas or natural gas is believed to be a cost-effective way for hydrogen-based infrastructure due to high cost of hydrogen transportation. In recent years, there have been a lot of on-site hydrogen fueling stations under design or construction in China. This study introduces current developments and technology prospects of skid-mounted SMR hydrogen generator. Also, technical solutions and economic analysis are discussed based on China's first on-site hydrogen fueling station project in Foshan. The cost of hydrogen product from skid-mounted SMR hydrogen generator is about 23 CNY/kg with 3.24 CNY/Nm³ natural gas. If hydrogen price is 60 CNY/kg, IRR of on-site hydrogen fueling station project reaches to 10.8%. While natural gas price fall to 2.3 CNY/Nm³, the hydrogen cost can be reduced to 18 CNY/kg, and IRR can be raised to 13.1%. The conclusion is that skid-mounted SMR technology has matured and is developing towards more compact and intelligent design, and will be a promising way for hydrogen fueling infrastructures in near future.     

A microfluidic approach for development of hybrid collagen-chitosan extracellular matrix-like membranes for on-chip cell cultures

To advance organ-on-a-chip development and other areas befitting from physiologically-relevant biomembranes,a microfluidic platform is presented for synthesis of biomembranes during gelation and investigation into their role as extracellular matrix supports.In this work,high-throughput studies of collagen,chitosan,and collagen-chitosan hybrid biomembranes were carried out to characterize and compare key properties as a function of the applied hydrodynamic conditions during gelation.Specifically,depending on the biopolymer material used,varying flow conditions during biomembrane gelation caused width,uniformity,and swelling ratio to be differently affected and controllable.Finally,cell viability studies of seeded fibroblasts were conducted,thus showing the potential for biological applications.     

道在山林，周弥六合——浙东天台山“洞天福地”的山岳景观流变及文化意象研究

道教洞天福地作为中国名山风景的经典类型之一，在宗教山岳景观中占据独特地位。浙东天台山水神秀，历代高道以入山隐修为主要目的，形成了道教在区域山林的景观文化基础。从天台山“神仙之乡”的文化背景出发，从“想象与实践”的视角切入，梳理了天台山洞天福地的景观流变：分析其“不死之福庭”地域性景观的形成经历了“赤城→桐柏”的信仰转移过程；以天台山为坐标，洞天福地格局打破了区域“层级”分布特征，而呈现大范围“州郡”空间格局。作为“联结点”的天台山，洞天世界沟通了宇宙、山、人3个基本场域，由此衍生出“洞宫”式和“周回”式山岳空间营建典范。旨在挖掘洞天福地中典型案例的价值，为中国洞天福地体系的构建提供理论依据。     

中国菊花主题花展及其对行业发展的作用

中国的菊花主题花展(菊花展览)是最重要的赏菊形式,对我国3种主要类型的菊花展览,即综合性菊花展览(中国菊花展览会、国际博览会菊花专项展和各级城市菊花展)、菊花专类园和菊花花田花海的发展现状进行了研究,并分析了菊花展览在促进菊花产业发展、弘扬菊花文化、服务生态文明及美丽乡村建设、加强菊花非物质文化遗产保护中的重要作用,为推动我国菊花展览水平的提高提供借鉴。     

Optimal resilient power grid operation during the course of a progressing wildfire

We study a two-stage stochastic and nonlinear optimization model for operating a power grid exposed to a natural disaster. Although this approach can be generalized to any natural hazard of continuous (and not instantaneous) nature, our focus is on wildfires. We assume that an approaching wildfire impacts the power grid by reducing the transmission capacity of its overhead lines. At the time when proactive decisions have to be taken, the severity of the wildfire is not known. This introduces uncertainty. In this paper, we extend previous work by more realistically capturing this uncertainty and by strengthening the mathematical programming formulation through standard reformulation techniques. With these reformulation techniques, the resulting two-stage, convex mixed-integer quadratically constrained programming formulation can be efficiently solved using commercial quadratic programming solvers as demonstrated on a case study on a modified version of the IEEE 123-bus test system with 100 scenarios. We also quantify the uncertainties through a second case study using the following three standard metrics of two-stage stochastic optimization: the expected value of perfect information, the expected result of using the expected value solution and the value of the stochastic solution.     

Mímir: An open-source semantic search framework for interactive information seeking and discovery

Semantic search is gradually establishing itself as the next generation search paradigm, which meets better a wider range of information needs, as compared to traditional full-text search. At the same time, however, expanding search towards document structure and external, formal knowledge sources (e.g. LOD resources) remains challenging, especially with respect to efficiency, usability, and scalability.This paper introduces Mímir—an open-source framework for integrated semantic search over text, document structure, linguistic annotations, and formal semantic knowledge. Mímir supports complex structural queries, as well as basic keyword search.Exploratory search and sense-making are supported through information visualisation interfaces, such as co-occurrence matrices and term clouds. There is also an interactive retrieval interface, where users can save, refine, and analyse the results of a semantic search over time. The more well-studied precision-oriented information seeking searches are also well supported.The generic and extensible nature of the Mímir platform is demonstrated through three different, real-world applications, one of which required indexing and search over tens of millions of documents and fifty to hundred times as many semantic annotations. Scaling up to over 150 million documents was also accomplished, via index federation and cloud-based deployment.     

致密油藏注天然气提高采收率研究现状

随着我国石油需求量不断增加,致密油藏的开发也愈发重要。如何高效开发致密油藏是一项重点难点,其中致密油藏注天然气提高采收率是一个极具潜力的研究方向。因此,本文着重介绍以天然气作为能量补充介质在国内外的研究现状和应用现状,并且从两相特征等方面总结了理论研究中的一些机理,对致密油藏注天然气提高采收率的发展前景进行了一定的展望。     

柯克亚油气田混合来源天然气的地球化学特征

柯克亚油气田是我国开发比较早的一个油气田,但由于受混源和其他因素的影响,对气源的认识众说纷纭。通过对天然气的地球化学特征的分析,并参照国内外关于甲烷、乙烷、丙烷碳同位素关系方面的资料,提出了如下看法:柯克亚天然气碳同位素相对较重,与塔里木盆地下古生界海相天然气的碳同位素组成区别较大;根据天然气40Ar/36Ar组成,柯克亚油气田的气源不是单一来源;柯克亚油气田绝大多数天然气的甲烷和乙烷碳同位素值关系符合Faber推断的 型有机质方程直线关系,说明有机质属于较好的有机质类型,或者是由原油裂解形成的天然气;除了K2井和K18井天然气成熟度较低以外,绝大多数天然气的成熟度大约在1.8%～2.2%之间,属于高过成熟气,但也混有一些成熟度在0.9%～1.2%的源岩形成的天然气;推测天然气主要来源于石炭系―二叠系源岩,而混有成熟度低的源岩形成的天然气则有可能来自侏罗系源岩。     

输气管线中水合物的形成及预防

天然气管道输送过程中因地貌、气象及各种管道条件而使少量天然气形成水合物，导致堵塞管线，影响管线的安全运行。分析了输气管线中形成水合物的热力学和动力学条件，其中在热力学条件中着重介绍了管道中含水量对形成水合物的影响，结合两方面条件简要介绍了预防水合物的常用措施。