本文采用溶剂热法合成了微孔结构的锆基金属-有机框架(MOFs)材料Zr-CAU-24,该材料比表面积为1610 m 2/g。对所合成的Zr-CAU-24进行了热重分析(TGA)和辐照稳定性测试,考察了接触时间、初始pH值等对Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)吸附性能的影...本文采用溶剂热法合成了微孔结构的锆基金属-有机框架(MOFs)材料Zr-CAU-24,该材料比表面积为1610 m 2/g。对所合成的Zr-CAU-24进行了热重分析(TGA)和辐照稳定性测试,考察了接触时间、初始pH值等对Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)吸附性能的影响,并探讨了Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)吸附过程的动力学和热力学。结果表明:Zr-CAU-24具有良好的热稳定性和辐照稳定性;准二级动力学模型为Th(Ⅳ)和Ce(Ⅳ)在Zr-CAU-24上的吸附过程提供了很好的解释,即该过程为化学吸附过程;Zr-CAU-24活性位点分布均匀,为单层吸附;混合金属离子溶液吸附研究发现,Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)具有吸附选择性。展开更多
For magmatic rocks,it is often found that zircon 206 Pb/238 U and 207 Pb/235 U ratios continuously plot on the concordia line with a relatively large age span for the same sample,which gives rise to large dating error...For magmatic rocks,it is often found that zircon 206 Pb/238 U and 207 Pb/235 U ratios continuously plot on the concordia line with a relatively large age span for the same sample,which gives rise to large dating errors or even unrealistic dating results.As the trace element concentrations of zircon can reflect its equilibrated magma characteristics,they can be used to determine whether all the analytical spots on the zircons selected to calculate the weighted mean age are cogenetic and formed in a single magma chamber.This work utilizes the results of zircon trace element concentrations and U-Pb isotopic analyses to explore the screening of reasonable U-Pb ages,which can be used to determine a more accurate intrusion crystallization age.The late Mesozoic Huayuangong granitic pluton complex,which is located in the Lower Yangtze region,eastern China,was selected for a case study.The Huayuangong pluton comprises the central intrusion and the marginal intrusion.Two samples from the marginal intrusion yielded consistent zircon weighted mean 206 Pb/238 U ages of 124.6±2.0 Ma and 125.9±1.6 Ma.These analytical spots also exhibit Zr/Hf and Th/U ratios concordant with the evolution of a single magma,from which the dated zircons crystallized.However,for the central intrusion,the analytical spots on zircons from two samples all show a continuous distribution on the concordia line with a relatively large age span.For each sample from the central intrusion,the zircon Zr/Hf ratios do not conform to a single magma evolutionary trend,but rather can be divided into two groups.We propose that zircon Zr/Hf ratios can provide a new constraint on U-Pb zircon dating and zircon Th/U ratios can also be used as a supplementary indicator to constrain zircon dating and determine the origins of the zircons and whether magma mixing has occurred.By screening zircon analytical spots using these two indicators,the two samples from the central intrusion of the Huayuangong pluton produce results of 122.8±4.3 Ma and 122.9±2.2 Ma,which are consistent with the field observations that the central intrusion is slightly younger than the marginal intrusion.展开更多
The beginning of a new year is always a time for reflection, contemplation and optimism. For the past thirty-five years, since its founding in 1980, Zoological Research (ZR) has experienced many highs and lows, seei...The beginning of a new year is always a time for reflection, contemplation and optimism. For the past thirty-five years, since its founding in 1980, Zoological Research (ZR) has experienced many highs and lows, seeing great advances but also overcoming numerous hurdles. Zoological Research has made many valuable contributions to the progress of biological sciences in China and won prestige both at home and abroad. Currently, it serves as a key journal focusing on Genome Evolution and Genetic Diversity, Animal Ecology and Ethology, Primates and Animal Models of Human Diseases. The journal also publishes high quality papers related to taxonomy and DNA barcoding, developmental biology, physiology biochemistry, immunology, and neuroscience. The growth achieved by ZR is not only due to our excellent readers and reviewers, but also to the evolution of our authors into renowned scholars. Accordingly, we would like to thank you all for your constant support and generous help.展开更多
文摘本文采用溶剂热法合成了微孔结构的锆基金属-有机框架(MOFs)材料Zr-CAU-24,该材料比表面积为1610 m 2/g。对所合成的Zr-CAU-24进行了热重分析(TGA)和辐照稳定性测试,考察了接触时间、初始pH值等对Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)吸附性能的影响,并探讨了Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)吸附过程的动力学和热力学。结果表明:Zr-CAU-24具有良好的热稳定性和辐照稳定性;准二级动力学模型为Th(Ⅳ)和Ce(Ⅳ)在Zr-CAU-24上的吸附过程提供了很好的解释,即该过程为化学吸附过程;Zr-CAU-24活性位点分布均匀,为单层吸附;混合金属离子溶液吸附研究发现,Zr-CAU-24对Th(Ⅳ)和Ce(Ⅳ)具有吸附选择性。
基金financially supported by the National Natural Science Foundation of China(Grant No.41672052)the National Key R&D Program of China(Grant No.2016YFC0600203)。
文摘For magmatic rocks,it is often found that zircon 206 Pb/238 U and 207 Pb/235 U ratios continuously plot on the concordia line with a relatively large age span for the same sample,which gives rise to large dating errors or even unrealistic dating results.As the trace element concentrations of zircon can reflect its equilibrated magma characteristics,they can be used to determine whether all the analytical spots on the zircons selected to calculate the weighted mean age are cogenetic and formed in a single magma chamber.This work utilizes the results of zircon trace element concentrations and U-Pb isotopic analyses to explore the screening of reasonable U-Pb ages,which can be used to determine a more accurate intrusion crystallization age.The late Mesozoic Huayuangong granitic pluton complex,which is located in the Lower Yangtze region,eastern China,was selected for a case study.The Huayuangong pluton comprises the central intrusion and the marginal intrusion.Two samples from the marginal intrusion yielded consistent zircon weighted mean 206 Pb/238 U ages of 124.6±2.0 Ma and 125.9±1.6 Ma.These analytical spots also exhibit Zr/Hf and Th/U ratios concordant with the evolution of a single magma,from which the dated zircons crystallized.However,for the central intrusion,the analytical spots on zircons from two samples all show a continuous distribution on the concordia line with a relatively large age span.For each sample from the central intrusion,the zircon Zr/Hf ratios do not conform to a single magma evolutionary trend,but rather can be divided into two groups.We propose that zircon Zr/Hf ratios can provide a new constraint on U-Pb zircon dating and zircon Th/U ratios can also be used as a supplementary indicator to constrain zircon dating and determine the origins of the zircons and whether magma mixing has occurred.By screening zircon analytical spots using these two indicators,the two samples from the central intrusion of the Huayuangong pluton produce results of 122.8±4.3 Ma and 122.9±2.2 Ma,which are consistent with the field observations that the central intrusion is slightly younger than the marginal intrusion.
文摘The beginning of a new year is always a time for reflection, contemplation and optimism. For the past thirty-five years, since its founding in 1980, Zoological Research (ZR) has experienced many highs and lows, seeing great advances but also overcoming numerous hurdles. Zoological Research has made many valuable contributions to the progress of biological sciences in China and won prestige both at home and abroad. Currently, it serves as a key journal focusing on Genome Evolution and Genetic Diversity, Animal Ecology and Ethology, Primates and Animal Models of Human Diseases. The journal also publishes high quality papers related to taxonomy and DNA barcoding, developmental biology, physiology biochemistry, immunology, and neuroscience. The growth achieved by ZR is not only due to our excellent readers and reviewers, but also to the evolution of our authors into renowned scholars. Accordingly, we would like to thank you all for your constant support and generous help.