Innovation and Development

Achievement in Heavy Ion Synchroaccelerator

On July 30, the cooler storage ring at the Heavy Ion Accelerator in Lanzhou (HIRFL-CSR), an important scientific facility undertaken by the Institute of Modern Physics, CAS passed national acceptance check. Experts hold that the project targets as stipulated for acceptance check are realized, of which, the energy and flow strength of accelerated carbon and argon beams in the main ring exceed the designed targets, making the cooler storage ring of the first large-scale heavy ion accelerator in China reach advanced level in the world. The acceptance check of HIRFL-CSR was organized by State Development and Reform Commission, and jointly presided over by Zhang Xiaoqiang, Vice Minister of State Development and Reform Commission, and Bai Chunli, Executive Vice President of CAS.

Started from April 2000, and with a total investment of 293.5 RMB million yuan, HIRFL-CSR features the first cooler storage ring system at a heavy ion synchroaccelerator fully accelerated by heavy ion built independently by China, with the largest scale and highest energy. The major construction contents included the improvement, construction and installation of main ring (CSRm), experimental ring (CSRe), radioactive beam (RIB) separator, experimental detecting device, radiation protective system, and heavy ion accelerator in Lanzhou (HIRFL), etc.

New Page for Full Organic Dye Materials for Solar Cells

The dye-sensitized solar cell (DSC) has attracted considerable attention as a promising technology for low-cost photovoltaics in the past two decades owing to its validated efficiency of over 11% and high performance under the prolonged light and thermal dual stress. Unfortunately, the stability of DSCs with organic sensitizers is disillusionary mainly due to the dye desorption from TiO2 nanocrystals. With a motivation to eliminate the dye desorption during the long-term device operation, a group lead by Prof. Wang Peng from the CAS Changchun Institute of Applied Chemistry has made a substantial progress on the R&D of metal-free organic sensitizers and the application in dye-sensitized solar cells (J. Am. Chem. Soc., 2008, 130, 9202). In combination with a solvent-free ionic liquid electrolyte (Nature Materials, 2008, 8, 626), they have demonstrated a ~7% cell showing an excellent stability measured under the thermal and light-soaking dual stress. For the first time they have proved that the dilemma between optical absorption and charge diffusion lengths can be overcomed via the rational molecular engineering of a high molar extinction coefficient organic sensitizer.

Transformation of Electron-Positron Collider Completed

On July 19, the accelerator of the upgraded Beijing Electron-Positron Collider (BEPCII) and Beijing Electron Spectrometer successfully produced the first collision after joint testing, where the physical case of collision between positive and negative electrons was observed. It symbolizes that BEPCII has completed the construction tasks with high quality, based on schedule and original budget and the performances of all the equipment have reached the requirements as designed, which will enter into the trial operation stage.

At present, the accelerator and the detector work stably and the collision luminosity is improved gradually, with the collision of 20 bunches of electrons and 20 bunches of positive electrons completed. It is expected that the targets as stipulated for acceptance check of BEPCII will be reached at the end of the year as planned. On such occasion, quality and statistical data are available for Beijing Electron Spectrometer, and great efforts will be made to offer synchrotron radiation users with special optical operations.

New Model to Control Bird Flu

The Research Group headed by Liu Yingfang, research fellow of the Institute of Biophysics, CAS, and the Joint Research Group of Nankai University-Tsinghua University-the Institute of Biophysics, CAS headed by Rao Zihe, member of CAS, have made a major breakthrough in the research of avian flue virus polymerase. The research result has filled in the gap in the research field of avian flu virus polymerase structure. Meanwhile, analysis on the structure offers a practical and effective model to explore the avian flu viral replication mechanisms, and for the design of anti-influenza virus drugs. The Nature online published the result on its July 9 Issue. This breakthrough takes the lead in revealing the fine three-dimensional structure of PA subunit and PB1 polypeptide compound in the key part of influenza virus polymerase in the world.