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Single-step conversion of lignin monomers to phenol: Bridging the gap between lignin and high-value chemicals

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Chinese Journal of Catalysis 2018年第9期39卷 1445-1452页

作者： Jiaguang Zhang Loris Lombardo Gokalp Gozaydin paul J.Dyson Ning Yan Department of Chemical and Biomolecular Engineering National University of Singapore117585 Singapore School of Chemistry University of LincolnJoseph Banks LaboratoriesGreen LaneLincolnLN6 7DLUnited Kingdom institute of Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne （EPFL） CH‐1015Switzerland

Transformation of lignin into high-value chemicals is hampered by the complexity of monomers obtained from lignin depolymerization. Here we report a strategy, composed of hy-dro-demethoxylation and de-alkylation reactions, that is able to chemically converge various lig-nin-derived phenolic monomers into phenol in a single-step. Using 2-methoxy-4-propylphenol as a model compound, Pt/C exhibited the best performance in hydro-demethoxylation reaction afford-ing 80% 4-propylphenol from 2-methoxy-4-propylphenol, while H-ZSM-5 was identified as the most suitable catalyst for de-alkylation, achieving 83% yield of phenol from 4-propylphenol. Since the two catalysts operate under compatible conditions, combining the two catalysts to simultane-ously promote both hydro-demethoxylation and de-alkylation reactions was achieved. Configura-tion of how to organize the catalysts is a critical parameter, where the physical mixture of the two was most effective, providing over 60% phenol from 2-methoxy-4-propylphenol in a single-step.

关键词： LigninPhenol ZeoliteDe‐alkylation Hydro‐demethoxylation

Cell Stem Cell：挑战常规!神经干细胞能够控制自己的命运

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现代生物医学进展 2016年第32期16卷 I0001-I0001页

作者： Chiara Rolando Andrea Erni Alice Grison Robert Beattie Anna Engler paul J. Gokhale Marta Milo Thomas Wegleiter Sebastian Jessberger Verdon Taylor Brain Research institute Faculty of Medicine and Science University of Zurich 8057 Zurich Switzerland

迄今为止，人们一直认为干细胞分化依赖于它们所在的环境。如今，在一项新的研究中，来自瑞士巴塞尔大学的一个研究团队首次描述了海马体神经干细胞通过蛋白Drosha调节它们自己的细胞命运的机制。相关研究结果在线发表在Cell Stem Cell... 详细信息

迄今为止，人们一直认为干细胞分化依赖于它们所在的环境。如今，在一项新的研究中，来自瑞士巴塞尔大学的一个研究团队首次描述了海马体神经干细胞通过蛋白Drosha调节它们自己的细胞命运的机制。相关研究结果在线发表在Cell Stem Cell期刊上，论文标题为”Mul6potency of Adult Hippocampal NSCs In Vivo Is Restricted by Drosha／NFIB”.

关键词：神经干细胞 Cell Stem 控制细胞分化 NSCs Vivo 巴塞尔

Let the sun shine into a brighter future:an interview with *** Steinfeld

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Science Bulletin 2017年第16期62卷 1102-1103页

作者： Yong Hao Wenjuan Zou Rui An institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Science China Press Beijing 100717China

Aldo Steinfeld(Ph.D.,University of Minnesota,1989)is a professor at the Department of Mechanical and Process Engineering of ETH Zurich,where he holds the Chair of Renewable Energy *** has pioneered the development of ... 详细信息

关键词：访谈录明尼苏达大学太阳能技术机械工程系光照化学反应器能源载体运输燃料

A Cluster Dynamics Model for Accumulation of Helium in Tungsten under Helium Ions and Neutron Irradiation

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Communications in Computational Physics 2012年第5期11卷 1547-1568页

作者： Y.G.Li W.H.Zhou R.H.Ning L.F.Huang Z.Zeng X.Ju Key Laboratory for Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei230031China Department of Physics University of Science and Technology BeijingBeijing 100083China

A cluster dynamics model based on rate theory has been developed to describe the accumulation and diffusion processes of helium in tungsten under helium implantation alone or synergistic irradiationwith neutron,by involving different types of objects,adopting up-to-date parameters and complex reaction processes as well as considering the diffusion process along with *** calculated results under different conditions are in good agreement with experiments much *** model describes the behavior of helium in tungsten within 2D space of defect type/size and depth on different ions incident conditions(energies and fluences)and material conditions(system temperature and existent sinks),by including the synergistic effect of helium-neutron irradiations and the influence of inherent sinks(dislocation lines and grain boundaries).The model,coded as IRadMat,would be universally applicable to the evolution of defects for ions/neutron irradiated on plasma-facing materials.

关键词： Cluster dynamics model rate theory helium and neutron irradiation tungsten accumulation and diffusion

Determining the Critical Fracture Stress of Al Dendrites near the Melting Point via Synchrotron X-ray Imaging

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 857-864页

作者： Ling Qin Zhiguo Zhang Baisong Guo Wei Li Jiawei Mi institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Department of Engineering University of HullEast YorkshireHU67RXUK Center of Innovation for Flow Through Porous Media Department of Petroleum EngineeringUniversity of WyomingLaramieWY82071USA Department of Materials University of OxfordOxfordOX13PHUK

Dendrites are the most common microstructural features in the cast metals,significantly affecting the structure integrity and mechanical properties of the *** this study,the in situ synchrotron X-ray radiographic and tomographic imaging techniques were combined to evaluate the critical fracture stress of the growing dendrite tip during the solidification of an Al-15 wt%Cu alloy under an external electromagnetic *** dendritic 3D models have been proposed to simulate the dendrite 3D morphologic characteristics and thus revealed that the critical fracture stresses of the Al dendrites at temperatures close to its melting point were in the range of 0.5 kPa–0.05 *** present results demonstrate the feasibility of measuring the high-temperature mechanical properties of the metallic dendrites.

关键词： Synchrotron X-ray radiography Tomography Al dendrite Fragmentation Critical fracture stress

Performances of an Active Target GEM-Based TPC for the AMADEUS Experiment

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Modern Instrumentation 2015年第3期4卷 32-41页

作者： Marco Poli Lener Giovanni Corradi Catalina Curceanu Diego Tagnani Antonio Romero Vidal Johann Zmeskal Laboratori Nazionali di Frascati dell’INFN Frascati Italy Universidad de Santiago de Compostela Santiago de Compostela Spain Stefan Meyer institute for Subatomic Physics Vienna Austria

In this paper, we present the R & D activity on a new GEM-based Time Projection Chamber (GEM-TPC) detector for the inner region of the AMADEUS experiment, which is aiming to perform measurements of low-energy negative kaon interactions in nuclei at the DAΦNE e+ e- collider at LNF-INFN. A novel idea of using a GEM-TPC as a low mass target and detector at the same time comes motivated by the need of studying the low energy interactions of K- with nuclei in a complete way, tracking and identifying all of the produced particles. Even more, what makes the experimental proposal revolutionary is the possibility of using different gaseous targets without any other substantial intervention on the experimental setup, making it a flexible multipurpose device. This new detection technique applied to the nuclear physics requires the use of low-radiation length materials and very pure light gases such as Hydrogen, Deuterium, Helium-3, Helium-4, etc. In order to evaluate the GEM-TPC performances, a 10 × 10 cm2 prototype with a drift gap of 15 cm has been realized. The detector was tested at the πM1 beam facility of the paul scherrer Institut (PSI) with low momentum pions and protons. Detection efficiency and spatial resolution, as a function of gas mixture, gas gain and ionazing particle, are reported and discussed.

关键词： GEM TPC Tracking Particle Identification

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发展中国家数据出版基础设施与共享政策研究

全球变化数据学报（中英文） 2017年第1期1卷 3-11,126-134页

作者：刘闯郭华东 paul F.Uhlir 葛全胜周翔石瑞香龚克 Mable Imbuga 顾行发 Mika Odido 廖小罕陈军 Tomoko Doko 陈文波 Simon Hodson Jean-Bernard Minster Edith Madela-Mntla Nordin Hasan 江东诸云强王长林 Peter Wittenburg 褚文博徐新良何书金吕婷婷 R.B.Singh Vladimir Tikunov 王桥中国科学院地理科学与资源研究所北京100101中国中国科学院遥感与数字地球研究所北京100101中国美国科学院美国华盛顿20541 南开大学天津300071 穆肯尼亚塔农业与技术大学肯尼亚内罗毕P.O.Box 62000-00200 联合国教科文组织东非办公室肯尼亚内罗毕P.O.Box 72107-00200 国家基础地理信息中心北京100830 庆应义塾大学日本藤泽2520882 国际科学技术数据委员会办公室法国巴黎75116 加州大学圣地亚哥分校美国加利福尼亚92093 国际科学理事会非洲办公室南非普利托利亚0020 国际科学理事会亚洲办公室马来西亚吉隆坡50450 马普学会数据基础设施中心德国莫尼黑85748 国际地球观测组织秘书处瑞士日内瓦1211 德里大学印度德里110007 莫斯科大学俄罗斯莫斯科119991 环境保护部卫星环境应用中心北京100094

全球变化科学数据是人类宝贵的科技资源。兼顾保护数据知识产权和推动数据广泛共享是科学数据界长期存在的普遍难题。数据出版(元数据、实体数据、数据论文关联出版)是解决这个难题的有效机制。发展中国家科学数据共享原则执行过程中,... 详细信息

全球变化科学数据是人类宝贵的科技资源。兼顾保护数据知识产权和推动数据广泛共享是科学数据界长期存在的普遍难题。数据出版(元数据、实体数据、数据论文关联出版)是解决这个难题的有效机制。发展中国家科学数据共享原则执行过程中,亟需数据出版基础设施和能力建设。"全球变化科学研究数据出版系统"(中英文)在保护数据知识产权和促进数据共享方面作出实践性案例,在数据产权认证、数据质量标准、同行专家评审、数据长期保藏、数据开放共享、国际资质联网等方面的成果为数据的增值起到关键性作用。《全球变化数据学报》(中英文)是该系统重要组成部分。该系统成为世界各国全球变化科学研究领域学者、特别是发展中国家学者可信赖的、国际组织(WDS、GEOSS、CODATA、Clarivate Analytics等)认可的、数据出版和共享世界性基础设施。

关键词：全球变化数据出版发展中国家数据基础设施共享政策