New breakthrough in high-end RF chip development

The world first WLAN IEEE802.11a/b/g ＋ DVB-H RF chip has been developed recently at the Suzhou-based CAS Semiconductor Integration Research and Development Center, a spinoff of the CAS Institute of Semiconductors.     

A new direction in search of “missing”carbon sinks

ACAS scientist succeeds in developing a new direction for exploring the inorganic carbon cycle of the earth. His creative work was recently reported by the 20th issue of Chinese Science Bulletin in 2007.     

Climate impact of changing landscape in tropical region

As China＇s major planting base for rubber trees （Hevea brasiliensis）,Xishuangbanna in southwest China＇s Yunnan Province has made tremendous contributions to the national economic growth. However, because the lands suitable for rubber plantations are largely distributed in tropical rainforests,the increasing rubber plantations have led to the acreage reduction of the local rainforests. These may irreversibly alternate the local ecological and environment systems, producing direct or indirect impact on climate. Of them, the changes in atmospheric chemistry are caused by the differences between biogenic volatile organic compounds （VOC） from rubber plantations and those of natural vegetation.     

Construction for neutrino experiment starts at Daya Bay

The ground-breaking ceremony for the Daya Reactor Neutrino Experiment,China's largest single project of international collaboration in basic science as well as the biggest one between US and China,was held at Daya Bay Nuclear Power Base in Shenzhen on 13 October,2007. Chaired by CHEN Hesheng, director of the CAS Institute of High Energy Physics(IHEP),the ceremony was attended by high-     

A new model for simulating evolution of human influenza virus

Understanding the evolution of influenza A virus, which poses a global challenge to public health, is of special significance for its control and prevention. Although the genome structure of the virus is seemingly simple, their evolutionary patterns and molecular mechanisms are difficult to reveal.     

Commissioning of a 3,500 ton/year synthetic gasoline facility

Using technologies developed by CAS researchers, a demo facility of coal-to-oil conversion with an annual capacity up to 3,500 tons was successfully commissioned on 11 December, 2007 at the Yunnan Jiehua Chem Group （JH Group） in Southwest China＇s Yunnan Province, producing qualified Ron 93 petrol.     

Introduction to the F. L. T. Terms

Needs Analysis An investigation, in the light of aspecification of the tasks a learner or group of learners will berequired to perform in the TL, of what particular aspects of theTL need to be learnt in order to bring about proficiency in theseparticular tasks. The results of the needs analysis can then beused to determine a syllabus and suitable teaching techniques. Norm(ⅰ) The mode of speech and the grammatical us     

退耕还林 40年来森林土壤氮库营养的动态变化研究(英文)

对 1962年以来采集的表层土壤和深层土壤样品进行培养实验,以研究退耕还林 40年来土壤氮的动态变化以及植被恢复对土壤氮库矿质化的影响.供试土样在专门设计的矿质化培养系统中,以温度 30℃、通气并保持土壤湿度的条件下培养 30d,以 2mol LKCl溶液浸提培养土并测定其氮含量.结果表明,土壤矿质氮及全氮含量均在造林的头 2 0年迅速下降,在 2 0年的林木生长过程中,生物吸收积累了土壤中约 80 %-90 %的有效氮,表明耕地中施入的氮对树木早期生长有着重要作用;树龄达 40年时,土壤原有矿质氮的 5 0 %-80 %已返还土壤.这一结果表明,森林地被已成为土壤营养的重要来源,并且森林生态系统提供的这种有机质可成为可持续利用的土壤氮资源.