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| 1 | Paleoenvironmental records from the northern South China Sea since the Last Glacial Maximum显示文摘Core ZHS-176 contains the paleoenvironmental records from the northern South China Sea (NSCS) since the Last Glacial Maximum (LGM). A coupled approach based on clay mineral assemblages, planktonic foraminiferal oxygen and carbon isotopes, and calcium carbonate content is used to trace the sources of the fine-grained sediment and to investigate the paleoenviornmental evolution in this area. Clay mineral assemblages are dominated by illite (average about 39%) and chlorite (about 27%), which comes mainly from Taiwan and the East China Sea. Kaolinite, which accounts for about 13%, comes mainly from the Zhujiang (Pearl) River, and Luzon Island is the main source for smectite (about 21%). The planktonic foraminiferal oxygen isotopic oscillations during the last glacial period are coeval with climate variations recorded in the Greenland ice core and Western Pacific sediment. These variations include the LGM, Heinrich event 1, Bφlling-Allerφd (B/A), and Younger Dryas. For the Holocene, three periods of strong precipitation (S1-S3) and three periods of weak precipitation (W1-W3) are identified. The oxygen isotopic record exhibits corre-lation with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global tele-connection among regional climate. A brief, negative planktonic foraminiferal carbon isotopic excursion during B/A reflects increased methane released from marine gas hydrate due to the rapid warming of the water. By comparing calcium carbonate content curves of the core ZHS-176 with these of other five boreholes lying above the lysocline, a remarkable low calcium carbonate event is found during the early Holocene in NSCS. | GE Qian CHU Fengyou XUE Zuo LIU J Paul DU Yuansheng FANG Yinxia | 2010 | Acta Oceanologica Sinica2010，29，3： | 13 |
| 2 | Growth of a polymetallic nodule from northwestern continental margin of the South China Sea and its response to changes in paleoceanographical environment of the late Cenozoic显示文摘In the northern South China Sea,the accumulation of enormous quantities of terrigenous sediment during Cenozoic rendered well-developed polymetallic nodules very rare.In this study,we analyzed a polymetallic nodule from the northwestern continental margin of the South China Sea using microscopic mineralogical observation,electron probes,X-ray diffraction(XRD),ICP-MS,and Be isotope dating.We found the nodule's shell layers rich in different types of microstructures,including columnar,laminar,stack-like,petal-like,and porphyritic structures.The major mineral components of the nodule are MnO2.Unlike nodules from the eastern Pacific basin,this nodule has high contents in Fe,Si,Al,and REEs but low contents in Mn,Cu,Co,and Ni.The Mn/Fe ratio is also low and the average REEs content is 1370.4 ppm.There is a strong positive anomaly of Ce;and the Be(beryllium) isotope dating shows the initial time of growth of the nodule to be about 3.29 Ma.The inner compact layer formed from 3.29 Ma to about 1.83 Ma.The laminar and stack-like structures and the low contents of the terrigenous elements such as Fe,Si,REE,and Al indicate the paleoceanographical environment with weak undersea currents and favorable oxidizing conditions.From 1.83 Ma to 0.73 Ma,the growth rate of the nodule increased by about 3%;the microstructures formed during this period are stack-like and columnar.The contents of Si and Al are increased by nearly 10%,indicating an increase of terrigenous sediment input in the northern South China Sea.The content of Ce is decreased by about 16%,indicating a significant weakening of the oxidizing conditions at the seabed.From 0.73 Ma to 0.69 Ma,the growth rate of the nodule rapidly rose up to 8.27 times that of the nodule's average growth rate,and the contents of Fe,Al,and REEs in the layer also increased,forming a loose layer characterized by oolitic,granular,porphyritic,and petal-like structures,indicating the paleoceanographical environment with a high sedimemtation rate and abundant supply of terrigenous sediment in the northern South China Sea.From 0.69 Ma to 0.22 Ma,the growth rate of the nodule suddenly slowed and the outer compact layer formed.Contents of Fe,Si,REE,Al,Mn,Cu,Co,and Ni in this layer were significantly lower than in other layers.The main structures of the layer are laminar and fissure filling structures.These reflect the paleoceanographical environment with stable undersea currents,poor oxidizing conditions,and other conditions not conducive to nodule growth.The growth process of nodule S04-1DG-1 was found to respond sensitively to the changes of the paleoceanographical environment of the northern South China Sea during the late Cenozoic. | ZHANG ZhenGuo DU YuanSheng WU ChangHang FANG NianQiao YANG ShengXiong LIU Jian SONG ChengBing | 2013 | Science China Earth Sciences2013，56，3： | 5 |
| 3 | Effects of organic acids on dissolution of Fe and Mn from weathering coal gangue显示文摘Understanding the effects of organic acids(OA) on the transformation of Fe and Mn to surface water from the weathering coal gangue is of great bene?t to risk assessment and remediation strategies for contaminated water and soil. Based on the investigation on surface water in the central coal districts of the Guizhou Province, 18 water samples were collected for heavy metal analysis. The results indicated that the p H value of surface water is low(3.11–4.92), and Fe concentration(1.31–5.55 mg L^(-1)) and Mn concentration(1.90–5.71 mg L^(-1)) were, on average,10.86 and 34.33 times the limit of Surface Water Quality Standards, respectively. In order to evaluate the effects of the OA on the dissolution of Fe and Mn from the weathering coal gangue, column elution and batch leaching experiments were conducted. The results show that the low molecular weight of organic acids(LMWOAs, i.e., oxalic,tartaric, malic and citric acids) and fulvic acids signi?-cantly accelerated the dissolution of Fe and Mn; in addition, when the concentration of OA reached 25 mmol L^(-1),the concentrations of Fe, and Mn were 1.14–67.08 and1.11–2.32 times as high as those in 0.5 mmol L^(-1)OA,respectively. Furthermore, the migration of Fe and Mn was signi?cantly in?uenced by the p H and Eh, especially for Fe; the ion Mn was dissolved from the gangue more easily than the ion Fe in the column leaching, which was contrary to the results of batch leaching. | Zuyong Chen Fang Liu Tongda Bu Yuansheng Liu Jian Zhu | 2016 | Acta Geochimica2016，35，3： | 3 |
| 4 | Calculation of one-valued control limits by control chart of angles显示文摘 | LI Yuansheng FANG Ying ZHU Xianfeng | 2001 | J Chinese University of Mining and Technology2001，11，2： | 1 |
| 5 | Mobility Trends and Effects on the COVID-19 Epidemic-Hong Kong,China显示文摘Summary What is already known about this topic?Several outbreaks of coronavirus disease 2019(COVID-19)occurred in Hong Kong in 2020,and the response had varied results based on the strength of policy measures and on compliance of the population.What is added by this report?By analyzing data of COVID-19 cases in Hong Kong,combined with the Google Mobility Trends and Oxford COVID-19 Government Response Tracker. | Rongna Zhang Zuoru Liang Mingfan Pang Xinping Yang Jiewen Wu Yuansheng Fang Hanran Ji Xiaopeng Qi | 2021 | China CDC weekly2021，3，8： | 0 |
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