[en] The reliability of uranium-series dating of fossil bones and teeth is studied. On this basis the first absolute chronology for about 20 important Chinese palaeolithic sites is proposed. A two-stage model for open-system samples is discussed. (author)

[en] The possibility and problems of using radiocarbon dating to historical chronology are discussed. The current situation of ancient Chinese chronology and the project of Xia-Shang-Zhou chronology are introduced. A chronological study requires the AMS radiocarbon dating with high precision, high reliability and high efficiency. The Peking University AMS facility (PKUAMS) has been upgraded and a series of quality control steps were adopted. To reduce the error of calendar age, wiggle matching with serial samples should be used. Some preliminary results of Xia-Shang-Zhou chronology are presented

[en] CN analyzer was already applied in CO₂ preparation system for AMS dating in the Research Lab for Archaeology and the History of Art in Oxford several years ago . Now a line of combustion with an Elementar Vario EL CHNS elemental analyzer was built in the Dating Lab in the Department of Archaeology at Peking University. This system has many advantages, such as obtaining purer CO₂, simultaneously measuring C, N, S etc. elements and C/N. A sample gases (i.e., CO₂, CO etc.) recollection system was also built in this lab to recover the CO₂ in case of the failure of graphitization

[en] Neutron activation analysis (NAA), in combination with multivariate analysis of the generated data, was used for the provenance study of the Terracotta Army of Qin Shihuang, the first Emperor of the first unified country of China. Using NAA, we measured the chemical composition of 30 shreds of the Terracotta Army and 29 clay samples from six resources in Lintong around Qin Shihuang Mausoleum. Although quite a few elements were determined, 8 elements were used for grouping the shreds and raw clay samples. By the statistical methods, some of clay samples close to the mausoleum present a chemical composition similar to that of the Terracotta Army, which hints these the raw clay resources were likely applied for the production of the Terracotta Army of Qin Shihuang

[en] Bone sample preparation has been studied in detail to find a suitable method for the processing of smaller sample amounts such as oracle bones. In a recent research project only 1 g of bone material will be available for radiocarbon dating of these valuable bones with the AMS method. The standard methods for the preparation of gelatin were compared with the amino acids treated by XAD-2 resin. Additionally, it was tested if the alkaline step in the procedure may be skipped or not. According to our results we may conclude that for well preserved bones the gelatin production yields reliable results. We could also show that the XAD-2 treatment is an effective method for the removal of humic acids

[en] To meet the requirements of the Xia-Shang-Zhou Chronology project, an upgrade of the AMS facility at Peking University has been carried out, commencing in 1996, and a new sample preparation system with high efficiency and low memory has been set up in the Department of Archaeology. A NEC MC-SNICS ion source has been installed and the injection system has been reconstructed. Computer control of the beam line has been implemented using Group 3 ControlNet, and a new data acquisition system has been developed. The alignment and vacuum of the beam line have also been improved. The upgraded system was commissioned in 1998. Subsequent experience has led to efficient procedures for beam tuning and ¹⁴C/¹³C measurement. A precision of 0.5% in the ¹⁴C/¹³C ratio has been achieved. Many samples have now been measured for the Xia-Shang-Zhou Chronology project

[en] Since May 1993, PKUAMS began routine ¹⁴C measurements and 520 ¹⁴C samples were measured from May 1993 to June 1994. Applications in the fields of geoscience, archaeology, environmental science and biomedical science have progressed. To study changing paleoclimates in arid and semi-arid area of northern China, a loess profile at Weinan, Shaanxi Province has been dated with high-resolution. The authors also studied the changing paleoenvironments in high resolution with a stalagmite of 1.2 m height taken from Panlong Cave, Guilin. AMS ¹⁴C dating with micro-stratification sampling shows that the deposition rate varied from 0.12 - 28 cm per 100 a during the past 30 ka. To study the transition from the Paleolithic to the Neolithic in South China, samples taken from Bailian Cave site, Liuzhou, were measured and some valuable data were obtained. The origin of pottery manufactory, wheat cultivation and metallurgy were also investigated. To identify the sources of atmospheric aerosols, carbonaceous species were collected from different districts during both cold and ward seasons. The measurement results show that the carbonaceous species have different source characteristics from trace element species. In biomedical research the author measured DNA adducts with ¹⁴C-labelled nicotine-derived nitrosamine (NNK). An extremely low detection limit of 1 adduct per 10¹¹ nucleotides were achieved, which is 3-6 orders of magnitude better than other techniques used for quantitative assay of DNA adducts

[en] With the prominent advantages of super sensitivity, small sample and high throughput, AMS has been developed rapidly during the past two decades in the world. Its application covers a large variety of fields including earth science, archaeology, physics, environment, material and biological science. Peking University Accelerator Mass Spectrometry (PKUAMS) facilities were established in 1991 and have been put into routine ¹⁴C measurement since May, 1993. Since then over 650 samples in diverse application fields have been measured and a series of valuable achievements have been gotten. The authors introduce the facilities systematically and present the methods of ¹⁴C measurement in detail

[en] To study the paleoclimate in China, high resolution AMS radiocarbon dating of a loess profile at Weinan, Shaanxi Province, had been carried out and the beginning of the Holocene in the investigated areas was estimated to be 10300 a B.P.. In southern China, a stalagmite of 1.2 m long taken from Panlongdong Cave, Guilin, Guangxi Autonomous Region, had also been studied. Dating with high resolution sampling showed that the climate during the Holocene in this area was generally damp and warm, but there was a short cold period during 10000-11000 a B.P.. The resolution of the AMS radiocarbon dating of stalagmite is about 100 years for the warm and damp period and about 500 years for the dry and cold period due to the slow deposition rate

[en] The Peking University Accelerator Mass Spectrometer (PKUAMS) has been put into routine operation. ¹⁴C measurements of archaeological samples with fast cycling injection have shown good results. The new multi-target high-intensity sputtering ion source has been tested and ¹⁰Be measurements were carried out with a new detector in which both the stopping of the intense flux of ¹⁰B ions and the identification of ¹⁰Be ions are performed. ²⁶Al samples were also measured. While various applications show good prospects for PKUAMS, further upgrade is desirable