HeⅠ photoelectron spectrum of isotopic 18O2 molecules has been firstly recorded on a double-chambers UPS machine Ⅱ which was built specifically to detect transient species. In comparison with UPS results of oxygen m...HeⅠ photoelectron spectrum of isotopic 18O2 molecules has been firstly recorded on a double-chambers UPS machine Ⅱ which was built specifically to detect transient species. In comparison with UPS results of oxygen molecles 16O2 it is found that the reduction of adiabatic ionization potentials IPs, the decresae of vibrational intervals and the change of intensity of vibrational components on each ionic state of isotopic 18O2molecules obviously appear on the UPS spectrum.展开更多
An 18--year-long (1981-1998) study was conducted in Hainan Island waters (22°20’N, 110°39’E) to determine the relationship between 618O in skeletal aragonite carbonate and sea surface temperature (SST) in ...An 18--year-long (1981-1998) study was conducted in Hainan Island waters (22°20’N, 110°39’E) to determine the relationship between 618O in skeletal aragonite carbonate and sea surface temperature (SST) in porites lutea of reef-building corals. 618O values in skeletal aragonite carbonate were measured by means of mass spectrometry. Coral samples grew at sin depth at Longwan Bay. Monthly measurements of the SST from 1960 to 1998 were taken at Qinglan Buy adjacent to the place of the collected samples. The thermometer shows that SST=-4.16 б~18O_PDB + 4.9 (r=0.80) and dб~18O/dT=-0.24 permil/°C. The б~18O thermometer is strongly influenced by the rainfall and runoff. Using the thermometer, the SST in the past hundred years with monthly resolution will be reconstructed and the climatic change in the northern area of South China Sea will be展开更多
PET FDG代谢显像已越来越多地应用于肿瘤的临床和研究,标准化摄取值(SUV)作为重要的半定量指标在PET图像分析中可以提供客观的参考数据。本文综述了SUV的计算及影响因素,以及其在肿瘤良、恶性鉴别、肿瘤分级、疗效监测、放疗和肿瘤预后...PET FDG代谢显像已越来越多地应用于肿瘤的临床和研究,标准化摄取值(SUV)作为重要的半定量指标在PET图像分析中可以提供客观的参考数据。本文综述了SUV的计算及影响因素,以及其在肿瘤良、恶性鉴别、肿瘤分级、疗效监测、放疗和肿瘤预后中的临床应用价值。SUV在肿瘤分级、判断疗效、放疗和预后中有较高的应用价值。在肿瘤的良、恶性鉴别中,正确运用SUV界值,可以提高诊断的灵敏度和特异性;但SUV不能作为判断良、恶性的唯一标准,在实际应用中仍需谨慎。展开更多
文摘HeⅠ photoelectron spectrum of isotopic 18O2 molecules has been firstly recorded on a double-chambers UPS machine Ⅱ which was built specifically to detect transient species. In comparison with UPS results of oxygen molecles 16O2 it is found that the reduction of adiabatic ionization potentials IPs, the decresae of vibrational intervals and the change of intensity of vibrational components on each ionic state of isotopic 18O2molecules obviously appear on the UPS spectrum.
基金NKBRSF Project Fund (G1999043401), National Natural Science Fundation(49776307), The innovation Project Fund of Chinese Academ
文摘An 18--year-long (1981-1998) study was conducted in Hainan Island waters (22°20’N, 110°39’E) to determine the relationship between 618O in skeletal aragonite carbonate and sea surface temperature (SST) in porites lutea of reef-building corals. 618O values in skeletal aragonite carbonate were measured by means of mass spectrometry. Coral samples grew at sin depth at Longwan Bay. Monthly measurements of the SST from 1960 to 1998 were taken at Qinglan Buy adjacent to the place of the collected samples. The thermometer shows that SST=-4.16 б~18O_PDB + 4.9 (r=0.80) and dб~18O/dT=-0.24 permil/°C. The б~18O thermometer is strongly influenced by the rainfall and runoff. Using the thermometer, the SST in the past hundred years with monthly resolution will be reconstructed and the climatic change in the northern area of South China Sea will be
