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| 1 | Pleniglacial millennium-scale climate variations in northern China based on records from the Salawusu River Valley显示文摘Situated in the Salawusu River Valley, southeast of China's Mu Us Desert, the MGS2 (Milanggouwan section) portion of the Milanggouwan stratigraphic section records 5.5 sedimentary cycles consisting of alternations between dune sand deposits and fluvial or lacustrine facies. We analyzed the grain-size and CaCO 3 distributions in MGS2, and found that Mz (mean particle diameter) and σ (standard deviation) displayed clear variations in peaks and valleys within different sedimentary facies. The CaCO 3 content averaged 0.4% in the dune sand deposits, 1.43% in the fluvial facies, and 8.82% in the lacustrine facies. Both the grain-size distribution and CaCO 3 contents, which equal the indicators for the alternation among the sedimentary facies, suggest the occurrence of 5.5 cycles. These results suggest that the observed cycles mainly resulted from fluctuations between a cold and dry winter monsoon climate and a warm and humid summer monsoon climate, and that the MGS2 portion experienced at least 5.5 fluctuations between these two extremes. This high-frequency climatic fluctuation indicates a strong influence of millennium-scale variations in the strength of the East Asian winter and summer monsoons in our study area during the Pleniglacial. | FengNian WANG BaoSheng LI JiangLong WANG XiaoHao WEN DongFeng NIU ZhiWen LI YueJun SI YiHua GUO ShuHuan DU | 2012 | Journal of Arid Land2012，4，3： | 7 |
| 2 | Grain-size distribution characteristics of red sandy sediments in Dongjiang River valley,southern Nanling Mountains,during the MIS2 stage显示文摘Layer LJ3 of Linjiang stratigraphic section in Dongjiang River valley in the south of the Nanling Mountains is a set of red sandy sediments.Measured by thermoluminescence(TL) dating,it was found to be formed in MIS2-9,500 ± 800 yr to 19,600 ± 1,800 yr B.P.After analy-sis of the grain sizes of the 16 samples(LJ3-100 to LJ3-85) in this layer,it was discovered that(1) The contents of each grain group in dif-ferent samples are similar.(2) The values of Md,Mz,,Sk,and Kg vary from LJ3-100 to LJ3-85 in a narrow range.(3) The segments of each sample in the accumulative curves extend parallel with similar slopes.All the three aspects reveal the Aeolian characteristics of Layer LJ3.Therefore,it is thought that Layer LJ3 consists of red sandy sediments formed in MIS2 in the south of Nanling Mountain,which reflects the arid climate at that time. | ShuHuan Du 1,BaoSheng Li 1,2,DongFeng Niu 1,XiaoHao Wen 1,FengNian Wang 1,XianJiao Ou 1,Yi Yang 1,YueJun Si 1,XinNan Zhao 1 1.Department of Geography,South China Normal University,Guangzhou,Guangdong 510631,China 2.State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an,Shaanxi 710061,China | 2009 | Research in Cold and Arid Regions2009，1，5： | 1 |
| 3 | Electrochemical Fabrication of Pd-Ag Alloy Nanowire Arrays in Anodic Alumina Oxide Template显示文摘The synthesis of Pd-Ag alloy nanowires in nanopores of porous anodic aluminum oxide (AAO) template by electrochemical deposition technique was reported.Pd-Ag alloy nanowires with 16%-25% Ag content are expected to serve as candidates of useful nanomaterials for the hydrogen sensors.Scanning electron microscopy (SEM) and energy dispersed X-ray spectroscopy (EDX) were employed to characterize the morphologies and compositions of the Pd-Ag nanowires.X-ray diffraction (XRD) was used to characterize the phase properties of the Pd-Ag nanowires.Pd-Ag alloy nanowire arrays with 17.28%-23.76% Ag content have been successfully fabricated by applying potentials ranging from -0.8 to -1.0 V (vs SCE).The sizes of the alloy nanowires are in agreement with the diameter of AAO nanopores.The underpotential deposition of Ag^+ on Pd and Au plays an important role in producing an exceptionally high Ag content in the alloy.Alloy compositions can still be controlled by adjusting the ion concentration ratio of Pd^(2+) and Ag^+ and the electrodeposition processes. XRD shows that nanowires obtained are in the form of alloy of Pd and Ag. | Erhong YUE Gang YU Yuejun OUYANG Baicheng WENG Weiwei SI Liyuan YE | 2008 | Journal of Materials Science & Technology2008，24，6： | 1 |
| 4 | Mycorrhizal Networks Interacting with Litter Improves Nutrients and Growth for One Plant through the Vary of N/P Ratio under Karst Soil显示文摘Arbuscular mycorrhizae(AM)fungi affect nutrient uptake for host plants,while it is unclear how AM fungi interacting with soil litter affect plant growth and nutrient utilization through mycorrhizal networks in karst soil of deficient nutrients beyond the rhizosphere.An experiment was conducted in a microcosm composed of a planting compartment for Cinnamomum camphora seedlings with or without Glomus mosseae fungus(M+vs.M−)and an adjacent litter compartment containing or not containing additional litter material of Arthraxon hispidus(L+vs.L−),where the compartments are connected either by nylon mesh of 20μm or 0.45μm which either allow available mycorrhizal networks within the litter compartment or prevent mycelium entering into the litter compartment(N+vs.N−).Plant biomass and nutrients were measured.The results showed that the addition of litter changed the symbiotic process in mycorrhizal colonization,spore,and hyphal density,which when in association with the host plant then affected the biomass,and accumulations of N(nitrogen)and P(phosphorus)in the individual plant as well as root,stem,and leaf respectively.AM fungi increased N and P accumulations and N/P ratio in individual plants and plant tissues.A decrease of the N/P ratio of the individual plant was observed when AM fungus interacted significantly with litter through mycorrhizal networks in the litter compartment.The results indicate that the C.camphora seedlings benefited from litter in nutrient utilization of N and P through the vary of N/P ratio when accessing mycorrhizal networks.These findings suggest that mycorrhizal networks interacting with litter improve growth and nutrients of N and P for plants through the vary of N/P ratio in order to alleviate nutrient limitation under karst soil. | Liling Kang Yuejun He Lipeng Zang Jianpeng Si Ying Yang Kaiping Shen Tingting Xia Qiyu Tan Bangli Wu Yun Guo Wei Wang Qin Liang | 2021 | Phyton-International Journal of Experimental Botany2021，90，3： | 0 |
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