牙化石珐琅样的ESR测年研究

报道了金牛山古人类遗址5个牙化石样品的ESR和铀系法对比测年结果。两种方法给出相近的23—24万年的年龄值。着重讨论了ESR测年中简单指数拟合求累积剂量的困难、α射线相对效率和氡逸失系数的实验测定以及应如何选择铀加入模式等问题。     

ESR法测牙珐琅化石年龄中累积剂量测量的初步研究

研究了牙珐琅化石的ＥＳＲ信号对辐射剂量的响应关系，讨论了用指数函数拟合定牙珐琅累积剂量ＡＤ的适用范围和所产生的系统误差的大小，并以郧县古人类遗址牙珐琅样品为实例检验了上述研究结果。     

羟基磷酸钙ESR信号热衰退中的二级动力学过程

人工合成羟基磷酸钙和牙珐琅化石的等温退火实验表明，它们的ＥＳＲ信号的热衰退系一级和二级动力学过程的混合效应。二级衰退常数强依赖于温度。粗测其值在２８０℃时为１０＾－１９ｇ／ｓ量级。二级过程的存在对ＥＳＲ法测早期古人类遗址动物牙化石年龄的影响需进一步研究。     

北京猿人遗址的ESR年代再研究

报道了第二批鹿牙样品的测年结果。采用新近发展的非线性拟合外推法获得样品的累积剂量。应用适合于牙釉质层样品的剂量率公式,计算了四种铀吸收模式的ESR年龄及其误差,得出了北京猿人遗址含有北京猿人头盖骨地层的年代分别为:第11层575±101ka,第8—9层409±72ka,第6—7层365±64ka和第3层290±51ka。     

南京直立人地层的ESR测年研究

用ＥＳＲ方法测得５个采自南京直立人地层化石牙珐琅样年龄的平均值为３５５±４２ｋａ。基于铀早期加入模式的ＥＳＲ测年的合理性为同地层牙化石样和方解石样的不平衡铀系测量所验证。研究结果认为南京直立人在时代上与晚期北京人相当而早于和县直立人。     

化石的ESR与U系,FT及TL的年龄对比

用铀的线性积累模式计算北京周口店猿人洞牙齿化石的ＥＳＲ年龄，并与Ｕ系、裂变径迹法和热释光法的年龄进行了对比，结果表明釉质齿最适合ＥＳＲ年龄的测定。     

用牙珐琅电子自旋共振法测定早更新世古人类与石器地点年代的探索

研究了用牙珐琅电子自旋共振测年法测定早更新世古人类和石器地点年代中存在的若干基本问题：（１）指数拟合能否较准确地测定累积剂量;（２）牙珐琅ＥＳＲ信号的热稳定性;（３）样品中铀加入模式;（４）珐琅中高铀含量对测年的影响。结果认为,对上述因素未完全了解和未做相应校正之前,早更新世牙珐琅的早期铀加入ＥＳＲ年龄都很可能只是真实年龄的下限。     

用牙珐琅电子自旅共振法测定早更新世古人类与石器地点年代的探索

研究了用牙珐琅电子自旅共振测年法测定早更新世古人类和石器地点年代中存在的若干基本问题：（1）指数拟合能否较准确地测定累积剂量;（2）牙珐琅ESR信号的热稳定性;（3）样品中铀加入模式;（4）珐琅中高铀含量对测年的影响。结果认为,对上述因素未完全了解和未做相应校正之前,早更新世牙珐琅的早期细加入ESR年龄很可能只是真实年龄的下限。     

河北泥河湾地层化石的电子自旋共振法测年及氨基酸测年

用电子自旋共振法测得泥河湾地层上部丽蚌－１、丽蚌－２化石样品的年龄分别为１．３６、１．２２Ｍａ；根据氨基酸外消法对测得泥河湾地层下部骨化石和丽蚌化石的年龄为２．７、２．９、２．７８Ｍａ等，由此可确定河北省泥河湾地层的第四纪时期标准地层的年龄。     

深海岩心有孔虫壳ESR测年的初步研究

用Ｕ的早期积累模式测定了中太平洋西部岩心有孔虫样品的ＥＳＲ年龄，所取５个层段样品年龄处于５０．１－２９８ｋａ，年龄误差为±１８％，从而为超出＾１４Ｃ测年范围的有孔虫样品提供了一种可行的定量测年方法。     

和县猿人及其动物群年代测定的初步研究

用电子自旋共振法对和县猿人头骨化石共生动物牙齿测年结果为距今３０（２９．９８）万年，印证了古人类学家对和县直立猿人相当于北京猿人（直立人）的晚期与ＨⅢ头骨年代相似的估计，另一动物牙齿测年数据与铀系封闭性的测年结果近似，表明和县猿人动物群生存于距今１５－３０万年。     

台湾云林浊水溪扇洲沉积层的热释光年代测定

用热释光测年法对台湾云林浊水溪扇洲沉积地层钻井不同深度岩芯的五个样品进行了初步测试，在５０ｋａ范围内样品的测年结果和＾１４Ｃ测年法的结果一致，这表明ＴＬ测年法对测定台湾第四纪沿岸沉积层年代是一个可行的方法。     

ELECTRON SPIN RESONANCE DATING FOR THE AGE OF PEKING-MAN, LOC.1, ZHOUKOUDIAN, BEIJING

In this paper, we used ESR dating method to measure the accumulative dose of the fossil teeth samples, which are contemporaneous with the Peking-Man. The internal annual dose rate of samples are got by neutron activation analysis and the environmental annual dose rate by highly sensitive TL dosimeters to be embedded in cave deposits in the site. The results of ESR dating are corresponded with the dating results obtained by U-series, FT, TL and paleomagnetic stratigraphical methods on the 3rd, 4th, 7th and 10th layers. Calculation of using different models, the close-equilibrium model, the linear uranium accumulation model and radon loss-linear uranium accumulation model, for travertine, deer teeth and rhinoceros tooth, we obtained the age of the First Peking- Man in the nth layer is 578 ka and gave ages of other layers, from the 1st to the 13th layer in Peking- Man site.     

Characterization of mercury gilding art objects by external proton beam

The fire gilding is one of the methods used by the ancient goldsmiths to obtain a rich, metallic glow and durable golden appearance in ornamental objects. This layer is characterized, among others, by its thickness (several microns) a diffusion profile and a Hg content (between 0 and 21 wt.%) depending on the temperatures achieved during the process. Gilded sacral art objects dated from the XVI to the XVIII centuries, belonging to the Casa-Museu Dr. Anastácio Gonçalves Collection (Lisbon) were analyzed using the external ion microprobe at Nuclear and Technological Institute, Lisbon. The average concentrations of the homogeneous areas were calculated with GUPIX, DATTPIXE and NDF codes showing very similar results. The RBS and PIXE spectra from the same point were collected simultaneously and analyzed together with NDF-LibCPIXE in order to find self-consistent solutions. Profile concentration on particular Au-reach points was extracted. Different Hg and Au/Ag ratio have been found in the pieces dating from different centuries.     

ESR模式年龄误差的初步探讨

应用间接测量的误差传递方法计算了铀的早期加入和线性积累的ESR模式年龄的误差,并对北京周口店猿人遗址动物牙釉的年龄作了误差分析,其结果均在±17％左右。     

MD simulation of atomic displacements in pure metals and metallic bilayers during low energy ion bombardment at 0 K

Molecular Dynamics (MD) simulations of 100 eV Ar ion bombardment of (1 0 0) Ni and Al crystals, of bilayer crystals consisting of an Al (or Ni) layer on a (1 0 0) Ni (or Al) substrate, as well as pseudo-isotope bilayer crystals have been performed at 0 K using tight-binding potentials. For these systems sputtering yields, energy deposition with depth, atomic relocations, production of ad-atoms, depth distributions of vacancies and interstitials per ion impact were studied for times up to 7 ps. We observed that both the mean square displacement of atoms and defect production (vacancies, interstitials and ad-atoms) are larger in pure Al than in pure Ni. In addition, we observed for the bilayer systems Al/Ni and Ni/Al a high number of the near surface atomic relocations; especially ion bombardment induced exchange processes between atoms of the 1st (Al or Ni) and of the 2nd (substrate) layer. Potential energy calculations indicate that such relocations between the 1st and the 2nd layer are in both bilayer crystals energetically favourable. Both Al/Ni and Ni/Al bilayers show considerable higher production of ad-atoms as the pure Al and Ni targets. Typically ad-atoms are from the first layer, but in the Ni/Al bilayer system we found a substantial amount of Al ad-atoms from the 2nd layer (first Al layer). They contribute more to the ad-atom number than 1st layer Ni atoms. The mean square displacement of atoms in Al/Ni and Ni/Al crystals increases considerably during the thermal stages of the cascade evolution while it is almost constant in the case of the pure Al and Ni. Finally we observed that the maximum kinetic energies of atoms in the cascade volume after 4 ps are lower in the Ni and Al/Ni crystals than in Al and Ni/Al crystals, reflecting the lower cohesive energy of Al as compared to Ni. Calculations with pseudo-isotope bilayer crystals were performed to elucidate the influence of mass or potential on the observed effects.     

泥河湾叠层石样品的ESR与铀系法测年对比

用ESR方法和铀系方法测定了泥河湾叠层石样品的年龄,进一步肯定了ESR方法测年的广泛适用性与可靠性,同时也验证了泥河湾这套河湖相沉积中的确包含有晚更新世的沉积物。     

Dating the Bibong-ri Neolithic site in Korea: Excavating the oldest ancient boat

The remains of an ancient wooden boat were unearthed at the Bibong-ri shell mound site. The site was located at Bibong-ri, Bugog-myeon, Changnyeong-gun, Gyeongsangnam-do in South Korea. A substantial fragment of the vessel was discovered in the lowest layer of the site. We collected 17 samples of charcoal and wood from pebble, sand, and shell layers. Sample preparation extracted the carbon from each sample material and converted it into graphite for AMS radiocarbon dating. Radiocarbon dates of the samples indicate that they belong to the Neolithic period and that the boat dates from ca. 5700 BC. To this point, the oldest known boat in the world has been a wooden boat dating from ca. 5500 BC in China. Other ancient boats from around the world include a logboat dating from ca. 3600 BC in Japan and a fleet of wooden boats dating from ca. 3000 BC in Egypt. The Bibong-ri boat is the first boat from the Neolithic period ever found in South Korea and must represent one of the world’s oldest known boats.