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1Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene显示文摘AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed.These three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon.The cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate change.Four stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable.LIU ShengFa SHI XueFa LIU YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing 2010Chinese Science Bulletin2010,55,21:25
2Clay mineral composition and their sources for the fluvial sediments of Taiwan Residents rivers显示文摘Located at the collision boundary between the Philippine Sea Plate and the Eurasian Continental Plate,the island of Taiwan is generally recognized as an important example in the MARGINS Program Science Plan and 'source-to-sink' research because of its high tectonic activity,heavy rainfall and unique geography.Large suspended sediment loads are transported to the adjacent ocean by Taiwan Residents rivers every year,making Taiwan an important source of sediments into the adjacent seas and a natural laboratory for studying the systemic movement of fluvial sediments from source to sink.A detailed study on the clay mineral composition of surface sediments collected from the drainage basins of 12 Taiwan Residents rivers using X-ray diffraction methods was conducted.Our results indicated that the clay mineral assemblages consisted dominantly of illite(approximately 73%) and chlorite(approximately 24%),with lesser abundances of kaolinite(approximately 3%) and even lower levels of smectite from the Danshuei River sediments in northwestern Taiwan.The Jhuoshuei River sediments from western Taiwan contained clay mineral assemblages that consisted of illite(approximately 75%) and chlorite(approximately 25%),but they lacked kaolinite and smectite.In southwestern Taiwan,the clay mineral assemblages were dominated by illite(approximately 75%) and chlorite(approximately 23%),but had a low abundance of kaolinite(generally < 2%) and no smectite.The clay mineral assemblages in eastern Taiwan are obviously different from those in western parts of the island.The most noticeable difference is that the average abundance of chlorite in the Hualien River from eastern Taiwan was the highest(approximately 48%) of all the Taiwan Residents rivers.We concluded that,in general,the clay mineral assemblages in Taiwan Residents rivers were mainly composed of illite and chlorite with kaolinite and smectite being scarce,and these trends are different from those in China's mainland rivers.The clay mineral composition shown in this study was primarily determined by the properties of the bedrock,and the differential weathering intensities of the drainage area.The surface sediments in Taiwan's rivers showed a greater abundance of illite and chlorite because the outcropped rocks were mainly composed of Tertiary sedimentary rocks,especially sandstone,shale and slate,and show strong physical weathering.The relatively high relief and more abundant rainfall also caused the clay minerals in the fluvial sediments to be transported to the estuaries down rivers from the mountains and then delivered to the adjacent seas by currents and waves over a shorter time scale.LI ChuanShun SHI XueFa KAO ShuhJi CHEN MinTe LIU YanGuang FANG XiSheng LUE HuaHua ZOU JianJun LIU ShengFa QIAO ShuQing 2012Chinese Science Bulletin2012,57,6:23
3Trend analysis of sediment grain size and sedimentary process in the central South Yellow Sea显示文摘With the method of trend analysis of sediment grain size, the sediment transport trend of the fine-grained sediments area in the central South Yellow Sea was studied. The results demonstrated that there is a sedimentation center around the point of 123.4° E, 35.1°N, and the sediments outside the center are transported to it. The patterns of sediment transportation and deposition in the Yellow Sea should be controlled by cyclonic circulation (including the Yellow Sea Cold Water Mass) and cold water gyre. The study also showed that the method of trend analysis of sediment grain size has prospective utilization in the fine-grained sediment deposited area on large-scale continental shelf.SHI Xuefa CHEN Chunfeng LIU Yanguang REN Hong WANG Huiyan 2002Chinese Science Bulletin2002,47,14:17
4Biomarker reconstruction of phytoplankton productiv-ity and community structure changes in the middle Okinawa Trough during the last 15 ka显示文摘Biomarkers have been widely used to reconstruct phytoplankton productivity and community structure changes, and this method has been applied for the first time in the middle Okinawa Trough during the transition from the last deglaciation to the Holocene. The total content of all marine phytoplankton biomarkers, used as a total productivity indicator, reveals higher productivity during the deglaciation. The ratios of the biomarkers are used as community structure indicators which show that, compared with the Holocene, the contribution from haptophytes decreased while the contributions from diatoms and dinoflagellates increased during the deglaciation. The increased productivity during the deglacia- tion was likely caused by the stronger winter monsoon. Also increased nutrient supply from terrestrial sources contributes to the higher productivity due to lower sea-level, which is consistent with higher terrestrial biomarker (long-chain n-alkanols) content. These changes in the nutrient supply also con- tributed to the community structure changes in the Okinawa Trough.XING Lei ZHAO MeiXun ZHANG HaiLong LIU YanGuang SHI XueFa 2008Chinese Science Bulletin2008,53,16:17
5Gravity and magnetic field and tectonic structure character in the southern Yellow Sea显示文摘The research of the geophysical survey in the cast of the southern Yellow Sea (SYS) (122°-125°E) in 1999 reveals that the SYS has a structure of three-uplifts and two-basins. The structure can be well concordant with the gravity and magnetic anomalies. In the basins, most of the gravity and magnetic anomalies are low and gentle. As well in the uplifts, the gravity anomalies are high positive ones,but the magnetic anomalies are plus and minus variant ones.Seismic data show that the mid-uplift is a Cenozoic one. The Paleozoic is under the Q+N strata, the thickness of which is less than 1 km, with no Palaeogene. The Wunansha uplift area and the Sunan uplift area have good continuity, which indicates that they belong to the same geological unit. The basin in the northern part of SYS, which developed in the late Cretaceous period, is a Cenozoic one mainly made up of Cenozoic sediment. On the contrary, the basin in the southern part is the seaward extension of Subei basin and is a medial Cenozoic sediment basin mainly made up of Cenozoic sediment. Because of the striking left-lateral sense translation of Tanlu fault zone, the east plate of fault zone moved northward on a large scale, which generated a massive north-south pull-apart stress field to make the earth crust pulled apart, revolved and tilted, and the pulling-apart basin came into being in the upper part of the crust.LIANG Ruicai, PEI Yanliang, ZHENG Yanpeng WEI Jianwei & LIU Yanguang Key Laboratory of Marine Sedimentolog and Environmental Geology, First Institute of Oceanography. State Oceanic Administration. Qingdao 266061. China 2003Chinese Science Bulletin2003,48,B06:12
6Sporopollen Assemblages from the Cretaceous Yimin Formation of the Hailar Basin,Inner Mongolia,China显示文摘Three sporopollen assemblages are recognized for the first time from the Cretaceous Yimin Formation in the Hailar Basin of eastern Inner Mongolia. They are (in ascending order): the Impardecispora-Aequitriradites-Clavatipollenites assemblage; the Triporoletes-Pilosisporites-Asteropollis assemblage; and the Appendicisporites-Asteropollis-Tricolpites assemblage, distributed in Members 1, 2 and 3 of the Yimin Formation respectively. Recognition of this biostratigraphic sequence is very important for the division and correlation of the Yimin Formation in the basin. Meanwhile, the age of the Yimin Formation is considered to be Barremian to Early Albian based on the palynological data.WAN Chuanbiao QIAO Xiuyun XU Yanbin SUN Yuewu REN Yanguang JIN Yudong GAO Ping LIU Tongyan 2005Acta Geologica Sinica(English Edition)2005,79,4:9
7Self-powered photoelectrochemical biosensing platform based on Au NPs@ZnO nanorods array显示文摘Photoanodes,它在 photoelectrochemical (PEC ) 被使用切开的水,被显示了在一个 PEC biosensing 平台的构造适用。这被用一个适当测试分子的氧化代替水氧化认识到。这里,我们表明了采用由为谷胱甘肽(GSH ) 的自我动力的 PEC bioanalysis 与 plasmonic 金牌 nanoparticles (Au NPs@ZnO NR ) 装饰在的锌氧化物 nanorods 数组组成的 photoanodes 的可行性缓冲磷酸盐盐(PBS ) 在 0 V 对 Ag/AgCl 的一个应用偏爱潜力。因为 Au/ZnO 接口的介绍,这 heterostructure 展出了提高的 PEC 性质。在可见轻照明下面,从在 Au NP 表面的表面电浆子回声(SPR ) 的热电子被注入邻近的 ZnO 并且随后开车到光阴极。在下面紫外(紫外) 轻照明,在 ZnO 的 photogenerated 电子趋于由于逐步的精力乐队结构和在 ZnO/ 电解质接口弯曲的向上的精力乐队转到做氟的符号的听氧化物。这些结果显示 plasmonic 金属 / 半导体 heterostructure photoanodes 为自我动力的 PEC bioanalysis 应用和另外的光电的烽火的扩大的地有大潜力。Zhuo Kang Xiaoqin Yan Yunfei Wang Yanguang Zhao Zhiming Bai Yichong Liu Kun Zhao Shiyao Cao Yue Zhang 2016Nano Research2016,9,2:8
8Turbidite and bottom-current evolution revealed by anisotropy of magnetic susceptibility of redox sediments in the Ulleung Basin,Sea of Japan显示文摘Anisotropy of magnetic susceptibility(AMS) from above and below 7.31 m in a core from the southern Ulleung Basin shows clear differences on an equal area projection of the lower hemisphere.Rather concentrated steep inclination of K 3 and horizontal inclination of K 1 and K 2(K1 ≥K2 ≥K3) are located within the upper part,and the latter two axes lie perpendicular to each other near the bedding plane.In contrast,random distribution of the three axes and extremely high value of shape parameters(Q=(K1-K2)/[(K1+K2)/2-K3]) are evident in the lower part,indicating complete destruction of the original sedimentary structure.This result is consistent with data from X-radiographs,which show numerous conglomerates,distortions and cleavages in the lower part.According to age models by Liu et al.(2010) and Zou et al.(2010),the bottom age at 7.31 m is 48 cal ka BP,and the time domain is discussed below.The degree of AMS(P) is low,1-1.08,and linearly related to the foliation(F)(R2 =0.95,N=176).The relationship between F and linearity(L) implies oblate aligning patterns that are typically sedimentary in origin.At least five redox couplets were found with the aid of S ratios and other rock magnetic parameters,and in most cases,the original signals of climate survived early diagenesis.The paleomagnetically reoriented AMS show corresponding changes with millennial events in the last 48 cal ka.Clearly tilted K 3 directions and reduction of P and F occurred within DO1-BA warm events,when melt water pulse 1A nd the YD cold event took place.The turbulent conditions therein,synchronous with coarsening of sediments,provide evidence of strong bottom currents and possible directional changes,as evidenced by different K3 tilting directions.A NE current direction in the last 4.5 cal ka is consistent with in situ measurements of bottom currents.Responses of AMS,mainly to climatic modulation,show on the one hand,the limited influence of diagenesis on rock magnetic signals and,on the other hand,the dramatic change of hydrodynamic conditions and terrigenous inputs during rapid sea level rise during the last deglaciation.GE ShuLan SHI XueFa LIU YanGuang WANG KunShan ZOU JianJun DIAO JingYu ZHU ZhiWei WANG ChunJuan 2012Chinese Science Bulletin2012,57,6:7
9Magnetostratigraphy of borehole EY02-2 in the southern Yellow Sea and its paleoenvironmental significance显示文摘Detailed rock magnetic and paleomag- netic studies have been undertaken on borehole EY02-2 (70m in length) in the southern Yellow Sea (SYS). The main Curie point revealed by magnetic susceptibility-temperature (k-T) curve is 580―600℃ indicating magnetite dominance. The hysteresis loop parameters show large variation of magnetic minera size in different sedimentary contexts: it is larger in subtidal sediment than in terrigenous sediment and even larger than in shallow sea sediment. This trend is correlative with distance to sediment source and dynamic strength. Magnetostratigraphic results show that the M/B polarity boundary (MBPB) is at 63.29m and there are at least 7 polarity transitions (Nr1-7) in Brunhes chron that can be tentatively correlated with 6 named polarity reversals. Three positive polarity reversals occur in late Matuyama chron and the early two may be the record of Kamikatsura happening in 886±3 kaB.P. Magnetic susceptibility (MS) and sediment grain size behave so differently in some sedimentary facies that certain big environmenta changes can be clearly revealed. Generally, the MS and grain size of subtidal and terrigenous sediments are larger than shallow sea sediments and MS value around 10×10?5SI and mean grain size of 7Φ seems to be indicators of shallow sea sediments of deep water depth. However, the frequently used excellen climatic proxies such as MS and grain size in loess and deep sea sediments fail to record such climatic cycles revealed by oxygen isotope in continental seaThe various sediment sources, sedimentation dy- namic and their complex changes between glacial and interglacial periods should be the cause of fail- ure.GE Shulan SHI Xuefa ZHU Rixiang LIU Yanguang YIN Ping LIU Lejun 2006Chinese Science Bulletin2006,51,7:6
10Distribution of major and trace elements in surface sediments of Hangzhou Bay in China显示文摘The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, the study area can be classified into three geochemical provinces. Province I covers the northern Hangzhou Bay area and contains high concentrations of Al_2 O_3 , Fe_2 O_3 , MgO, Na_2 O, K_2 O, MnO, Cr, Cu, Ni, Pb, V, Co and Zn. Province III is located in the western Hangzhou Bay, near the Qiantang River mouth, and contains high concentrations of SiO_2 , Na_2 O, P_2 O_5 , TiO_2 , Cr, Sr, Zr. Province II is located in the middle and eastern Hangzhou Bay, with the medium concentrations of major and trace elements. The results also demonstrate that the grain size is the dominating factor controlling the spatial variations of elemental concentrations, and the Changjiang River (Yangtze River) and Qiantang River sediments play an important role in the distribution of these elements. Anthropogenic impact on heavy metal concentrations (especially Cr, Sr and Zr) can be detected in the surface sediments near the Qiantang River mouth.LIU Shengfa LIU Yanguang YANG Gang QIAO Shuqing LI Chaoxin ZHU Zhiwei SHI Xuefa 2012Acta Oceanologica Sinica2012,31,4:5
11Terrestrial flux in sediments from the Okinawa Trough estimated using geochemical compositional data and its response to climate changes over the past 35000 a显示文摘Terrestrial supply to marginal seas is a function of interaction between land and ocean in response to climate changes.Terrestrial flux in sediments,therefore,is potential not only to reflect the paleoceanographic evolution of sedimentary basin,but also to reveal the paleoclimatic changes in source regions.Sediments from the Okinawa Trough were quantitatively partitioned into terrestrial,volcanic and biogenitic end members using constrained least-squares technique for geochemical compositional data.Combined with the density of bulk sediments and sedimentation rate,the terrestrial flux in sediments from the Okinawa Trough since the last 35 000 a was estimated.Based on surface seawater temperature(SST) and sea level changes over the past 35 000 a,the response of terrestrial flux to the climate changes was discussed.It is demonstrated that the terrestrial supply to the Okinawa Trough mainly derived from Chinese landmass via the Changjiang(Yangtze) River and controlled by sea level changes.During the post-glaciation,the terrestrial flux was the lowest in response to the highest sea level stand.During the last glacial maximum(LGM),the terrestrial flux was not so high as previously expected,indicating the arid climatic condition in source region was responsible for lowering the Changjiang River's runoff during that time.During the deglaciation,the terrestrial flux increased in response to a quick rising of the sea level,probably implicating occurrence of down-slope transport.The four events characterized by slight increase in terrestrial flux exactly correspond to the LGM,Heinrich events(H1,H2,H3),respectively.MENG Xianwei LIU Yanguang DU Dewen SHI Xuefa 2009Acta Oceanologica Sinica2009,28,1:5
12Holocene tephra deposits in the northern Okinawa Trough显示文摘The mineralogical and geochemical characteristics of sediments of Core CSH1, which was collected from the northern Okinawa Trough, indicate that large amounts of volcanic materials have deposited in the northern Okinawa Trough during the Holocene. On the basis of down-core variations in mineral and element contents of sediments, two layers in the uppermost section of Core CSH1 charac- terized by high quartz, Na2O, MnO, K2O, uranium contents and low contents of clay minerals, volatiles, Fe2O3, MgO, CaO and stron- tium, have been identified as the tephra deposits. Systematic grain-size measurements also suggest that sediments from the northern Okinawa Trough are made up of terrigenous materials and volcanic ashes with different proportion during the Holocene. The sedi- ments of tephra layers in Core CSH1 show bi-modal patterns in grain-size distribution with modal grain-sizes of 74.3 and 7.81 μm, respectively. According to the radiocarbon dating on shells of zooplankton foraminifera, two tephra layers in Core CSH1, formed at 7 250 and 10 870 a BP (cal), approximately correspond to the K-Ah tephra [7 300 a BP (cal)] and the eruption of Kuju Volcano (12 ̄10 ka BP), respectively.LIU Yanguang OLE BjФrslev Nielsen ZHANG Deyu DU Dewen JAN Heinemeier WU Yonghua 2006Acta Oceanologica Sinica2006,25,1:4
13Depositional environment in the southern Ulleung Basin,East Sea(Sea of Japan),during the last 48000 years显示文摘The present study is based on the sedimentological data from a piston core KCES1 off the southern Ulleung Basin margin,the East Sea(Sea of Japan).The data include sediment color(L*),X-ray radiographs,grain size distribution and AMS14C date.Four kinds of sediments(homogeneous,laminated,crudely laminated and hybrid sediments) are identified according to the characters of the sedimentary structures that were considered to reflect changes in bottom-water oxygenation.Alternations of dark laminated/crudely laminated sediments and light homogeneous sediments represent millennial-scale variations that are possibly associated with the high-resolution changes in the East Asian monsoon(EAM).The relative contributions of the East China Sea Coastal Water(ECSCW) and the Tsushima Warm Current(TWC) were likely the main reasons for the repetition of the anoxic and oxic depositional conditions in the East Sea since the last 48 ka BP.During the interstadial,the strengthen summer EAM was attributed to the expansion of the ECSCW because of more humid climate in central Asia,and then more strongly low-salinity,nutrient-enriched water was introduced into the East Sea.The ventilation of deep water was restricted and therefore the dark laminated layer deposited under the anoxic bottom water condition.During the lowest stand of sea level in the last glacial maximum(LGM),the isolated East Sea dominated by stratified water masses and the euxinic depositional environment formed.The homogenous sediments have been predominating since 17.5 ka BP indicating that the TWC has intruded into the East Sea gradually with the stepwise rise of sea level and the bottom water oxygen level was high.During the late Younger Dryas(YD) period,the last dark laminated layer deposited because the ventilation of bottom water was restricted by stronger summer EAM.The TWC strengthened and the bottom water became oxic again from 10.5 ka BP.LIU Yanguang SHA Longbin SHI Xuefa SUK Bong-Chool LI Chaoxin WANG Kunshan LI Xiaoyan 2010Acta Oceanologica Sinica2010,29,5:4
14The sedimentation rates in the Okinawa Trough during the Late Quaternary显示文摘On the basis of accelerator mass spectrometer radiocarbon (AMS14C) dating, sedimentation rates of 11 cores collected from thenorthern to southern Okinawa Trough are discussed. The sedimentation rates in the Okinawa Trough roughly range from 11 to 39cm/ka, and the average is 23.0 cm/ka. China’s continental matter is the main sediment source of the middle Okinawa Trough and hasimportant contribution to the northern and southern Okinawa Trough. The sedimentation rates during the marine oxygen isotope (MIS)2 are uniformly higher than those during MIS 1 in the northern and middle Okinawa Trough while they are on the contrary in thesouthern Okinawa Trough. Sedimentation rates in the Okinawa Trough can be one of the proxies of sediment source and an indicatorof cooling events.XIONG Yingqian LIU Zhenxia LI Tiegang LIU Yanguang YU Hua 2005Acta Oceanologica Sinica2005,24,4:3
15Environmental record from the mud area on the inner continental shelf of the East China Sea since the mid-Holocene显示文摘Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China Sea. The ancient environment featured low-energy shallow sea shelf deposition formed mainly by coastal currents. The results show that temporal variation in geochemistry corresponds with the climate changes inferred from historical record. Relatively low MgO/Al 2 O 3,CaO/K 2 O and high Al 2 O 3 /Na 2 O,K 2 O/Na 2 O,MnO/CaO values reflected a warm and humid climate in general,and vice versa. Therefore,these chemical indices could be applied to identify the variation of palaeoclimate in eastern China. The authors reconstructed the history of mid-Holocene climatic variation of the inner continental shelf of the East China Sea. From 8 300 a BP to 4 200 a BP,the climate was moderately warm and humid. From 4 200 a BP to 2 000 a BP,the climate turned cool and dry,and the regional climate frequently fluctuated in alternation of cool-dry periods(3 700 a BP,2 850 a BP and 2 400 a BP) and warm-wet periods(3 250 a BP and 2 650 a BP) . After 2 000 a BP,the climate of the study area gradually turned warm again,while the Little Ice Age,a cold event centered at around 250 a BP was indicated by those geochemical indices as mentioned above.LIU Shengfa SHI Xuefa LIU Yanguang WU Yonghua YANG Gang 2011Acta Oceanologica Sinica2011,30,4:3
16Osmium isotope of the Co-rich crust from seamount Allison, central Pacific and its use for determination of growth hiatus and growth age显示文摘Based on its microstructure, Co-rich crust A1-1 from seamount Allison, central Pacific, was scraped at averaged interval of 1.3 mm to measure osmium isotopic composition, and subsequently to establish the 187Os/188Os profile of scraping section of the crust. By observing the variation of 187Os/188Os under 10Be chronology and matching it to the well-known seawater Os isotope evolution of the past 40 Ma, two growth hiatuses (H1 and H2) occurring in the periods respectively between 13.6 and 29.6 Ma and between 8 and 9.8 Ma in the crust were recognized. According to the two hiatuses, the dating scheme for each scraped layer of the crust was suggested. For the upper layers younger than 6.8Ma, their growth ages were calibrated under 10Be chronology; for the lower layers older than 6.8Ma, their growth ages were obtained from 187Os/188Os evaluation curve by linear interpolation. Hereby, the age for the most inner layer of the crust was determined to be 39.5 Ma. H1 and H2 exactly correspond to the boundary between phosphatization and non-phosphatization and volcanic ash layer in the crust, respectively.MENG XianWei LIU YanGuang QU WenJun SHI XueFa 2008Science China Earth Sciences2008,51,10:2
17Palaeo-sea-ice changes on the North Icelandic shelf during the last millennium:Evidence from diatom records显示文摘A high resolution record of sea-ice concentration on the North Icelandic shelf during the last millennium has been reconstructed using a diatom-based sea-ice transfer function. The reconstructed sea-ice record for the top of sediment core MD99–2275 exhibits a slightly increasing trend over the last 1000 years. Prior to AD 1300 sea-ice abundance was generally below the mean value, suggesting the strong influence of warm waters from the Irminger Current during the Medieval Warm Period. A marked increase of sea-ice concentration indicates an abrupt change to colder conditions after AD 1300, corresponding to the onset of the Little Ice Age. The agreement between the reconstructed sea-ice concentration and IP25 data obtained from the same core, as well as with historical records of Icelandic sea ice, suggests that diatoms may provide a valuable tool for future quantitative reconstructions of past sea-ice variability. In addition, agreement between changes in the reconstructed sea-ice record and variations in the abundance of the major diatom components indicates that sea-ice conditions on the North Icelandic shelf are generally strongly influenced by changes in the strength of two different water masses, the cold Polar water periodically derived from the East Greenland Current and the warm Irminger Current derived from the North Atlantic Current. Our proxy evidence also indicates that variations in solar activity have a considerable impact on ocean dynamics, which in turn affects sea-ice abundance.SHA LongBin JIANG Hui LIU YanGuang ZHAO MeiXun LI DongLing CHEN ZhenLou ZHAO Yun 2015Science China Earth Sciences2015,58,6:2
18Variations of alkenone temperature in the Sea of Japan during the last 170 ka and its paleoceanographic implications显示文摘Two sediment cores, KCES1 and ODP797,which were recovered from the Sea of Japan(JS), were measured for alkenone-derived sea surface temperatures(UK037-SSTs). Our results revealed that the SSTs closely follow the glacial-interglacial cycles during the last 170 ka,except in the last glacial maximum(LGM), during which the SST was higher than in the Holocene. The anomalous high temperature in the LGM is considered as an effect of the intrusion of a low salinity water mass into the JS when the sea level was almost below 130 m. On the glacialinterglacial to orbital timescale, the UK037-SSTs record in the JS correlated well with the benthic foraminiferal d18 O record and solar insolation, which suggests the dominant control of solar insolation and its related sea ice development on the SST in the JS. On the sub-orbital/millennial timescale, reduced SST corresponds to an enhanced east asian winter monsoon(EAWM) during the last glacial period(MIS3 and MIS4), indicating the dominant control of sea ice expansion due to the enhanced EAWM on the SST in the JS. In contrast, during the last interglacial period(MIS5), the SST in the JS was controlled by variations in the east Asian summer monsoon. These results highlight the key role of solar insolation and associated glacialinterglacial conditions in the variations of the SST in the JS since the last 170 ka.Yanguang Liu Jiaojie Chen Jinxia Chen Lei Xing Jianjun Zou Zhengquan Yao 2014Chinese Science Bulletin2014,59,33:2
19Research on flow stress of spray formed 70Si30Al alloy under hot compression deformation显示文摘The flow stress of spray formed 70Si30Al alloy was studied by hot compression on a Gleeble-1500 test machine. The experimental results indicated that the flow stress depends on the strain rate and the deformation temperature. The flow stress increases with an increase in strain rate at a given deformation temperature. The flow stress decreases with the defor- mation temperature increasing at a given strain rate. The relational expression among the flow stress, the strain rate, and the deformation temperature satisfies the Arrhenius equation. The deformation activation energy of 70Si30Al alloy during hot deformation is 866.27 kJ/mol from the Arrhenius equation.WEI Yanguang XIONG Baiqing ZHANG Yong'an LIU Hongwei ZHU Baohong WANG feng 2006Rare Metals2006,25,6:2
20Spatial Autocorrelation and Localization of Urban Development显示文摘A nonlinear analysis of urban evolution is made by using of spatial autocorrelation theory. A first-order nonlinear autoregression model based on Clark’s negative exponential model is proposed to show urban population density. The new method and model are applied to Hangzhou City, China, as an example. The average distance of population activities, the auto-correlation coefficient of urban population density, and the auto-regressive function values all show trends of gradual increase from 1964 to 2000, but there always is a sharp first-order cutoff in the partial auto- correlations. These results indicate that urban development is a process of localization. The discovery of urban locality is significant to improve the cellular-automata-based urban simulation of modeling spatial complexity.LIU Jisheng CHEN Yanguang 2007Chinese Geographical Science2007,17,1:2
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