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Li B.-J.,CAS Beijing National Laboratory for Molecular | Shi Z.-J.,CAS Beijing National Laboratory for Molecular | Shi Z.-J.,Chinese Academy of Sciences
Chemical Society Reviews | Year: 2012

In this tutorial review, we will summarize our recent efforts in transition metal-catalyzed oxidative coupling via C-H functionalization of aromatic, benzylic and allylic C-H bonds. Related works from other laboratories will be cited where suitable, aiming to give the readers a flavor of this field. Special emphasis is placed on the reaction design and development. © The Royal Society of Chemistry 2012.

Yuan F.,Chinese Academy of Sciences | Narayan R.,Harvard - Smithsonian Center for Astrophysics
Annual Review of Astronomy and Astrophysics | Year: 2014

Black hole accretion flows can be divided into two broad classes: cold and hot. Whereas cold accretion flows consist of cool optically thick gas and are found at relatively high mass accretion rates, hot accretion flows, the topic of this review, are virially hot and optically thin, and occur at lower mass accretion rates. They are described by accretion solutions such as the advection-dominated accretion flow and luminous hot accretion flow. Because of energy advection, the radiative efficiency of these flows is in general lower than that of a standard thin accretion disk. Moreover, the efficiency decreases with decreasing mass accretion rate. Observations show that hot accretion flows are associated with jets. In addition, theoretical arguments suggest that hot flows should produce strong winds. Hot accretion flows are believed to be present in low-luminosity active galactic nuclei and in black hole X-ray binaries in the hard and quiescent states. The prototype is Sgr A, the ultralow-luminosity supermassive black hole at our Galactic center. The jet, wind, and radiation from a supermassive black hole with a hot accretion flow can interact with the external interstellar medium and modify the evolution of the host galaxy. Copyright © 2014 by Annual Reviews.

Liu Y.,CAS Changchun Institute of Applied Chemistry | Liu Y.,Chinese Academy of Sciences | Ai K.,CAS Changchun Institute of Applied Chemistry | Lu L.,CAS Changchun Institute of Applied Chemistry
Chemical Reviews | Year: 2014

Polydopamine is fast becoming a popular polymer that is receiving increased attention from scientists from different areas of expertise. The physicochemical properties of polydopamine, as well as its potential applications are reviewed. Similar to the foot protein in mussels, polydopamine has also shown versatile adhesion capability to virtually all types of surfaces, and provides a general surface-coating strategy for researchers to functionalize some specific technique-related substrates. It easily reacts with numerous amine- and thiol-containing molecules based on Michael-type addition and Schiff base reactions and has strong metal chelating/redox capabilities, which imparts to materials with structural flexibility and the ability to tailor the coatings for producing diverse hybrid materials with specific functionalities. During investigations of the polymerization process, specific attention should be drawn to the thickness of the polydopamine film deposited on the substrates.

Fang Y.,Chinese Academy of Sciences
Renewable and Sustainable Energy Reviews | Year: 2011

Over the last years renewable energy sources have increased their share on electricity generation of China due to environmental and security of supply concerns. In this work author assesses the role of both the amount and share of renewable energy consumption in economic welfare using Cobb-Douglas type production functions. This assessment is carried out by multivariate OLS and SPSS software for China from 1978 to 2008. Results indicate that a 1% increase in renewable energy consumption (REC) increases real GDP by 0.120%, GDP per capita by 0.162%, per capita annual income of rural households by 0.444%, and per capita annual income of urban households by 0.368% respectively; the impact of renewable energy consumption share (SREC) on economic welfare is insignificant, and an increasing share of REC negatively affects economic welfare growth to a certain extent. In this paper, the cost, structural demand, accounting mechanism and policy reasons of renewable energy development are interpreted. Marginal effects analysis show that the shape of sound and robust renewable energy institutions and policies would matter for increasing the standards of economic welfare in the context of speeding up renewable energy development and increasing share of renewable energy consumption, especially the goal-oriented policy refinement should be addressed efficiently in improvement households income while increasing share of renewable energy consumption. © 2011 Elsevier Ltd. All rights reserved.

Tong H.,Chinese Academy of Sciences
Astrophysical Journal | Year: 2014

The anti-glitch of magnetar 1E 2259+586 is analyzed theoretically. An enhanced particle wind during the observational interval takes away additional rotational energy of the neutron star, which will result in a net spin-down of the magnetar, i.e., an anti-glitch. In the wind braking scenario of the anti-glitch, there are several predictions: (1) a radiative event will always accompany the anti-glitch, (2) there will be a decrease/variation of the braking index after the anti-glitch, and (3) the anti-glitch is just a period of enhanced spin-down. If there are enough timing observations, a period of enhanced spin-down is expected instead of an anti-glitch. Applications to previous timing events of SGR 1900+14 and PSR J1846-0258 are also included. It is shown that current timing events of 1E 2259+586, SGR 1900+14, and PSR J1846-0258 can be understood safely in the wind braking model. The enhanced spin-down and absence of an anti-glitch before the giant flare of SGR 1806-20 is consistent with the wind braking scenario. © 2014. The American Astronomical Society. All rights reserved.

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