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黄宗羲后裔对《宋元学案》的补修及其学术史意义 被引量:1
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作者 金晓刚 《浙江师范大学学报(社会科学版)》 2022年第2期26-34,共9页
黄宗羲后裔在《宋元学案》书稿的流传及成书过程中发挥了重要作用。黄璋、黄征等人除借抄、保存及续补文献外,所撰119条案语涉及对宋元理学史的考订、评骘,彰显出自己的学术见解。从学案设置、命名、人物评价来看,黄璋父子的续补,并非... 黄宗羲后裔在《宋元学案》书稿的流传及成书过程中发挥了重要作用。黄璋、黄征等人除借抄、保存及续补文献外,所撰119条案语涉及对宋元理学史的考订、评骘,彰显出自己的学术见解。从学案设置、命名、人物评价来看,黄璋父子的续补,并非此前所认为的回到梨洲原本,否定全氏补本,而是在综合梨洲、谢山两家观点的基础上,形成自己的判识,一定程度折射出清代浙东学派思想的继承与转向。 展开更多
关键词 《宋元学案》 黄璋 黄征■ 学术史观
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Morphological Difference and Karyotype of Pelteobagrus fulvidraco in Dongting Lake Water System 被引量:4
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作者 刘良国 邹万生 +2 位作者 杨春英 罗玉双 杨品红 《Agricultural Science & Technology》 CAS 2011年第10期1521-1524,共4页
[Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchi... [Objective] The research aimed to study the morphological characteristics and karyotype of Pelteobagrus fulvidraco in Dongting Lake water system.[Method] By using the conventional biological morphometry,PHA and colchicine injection method in vivo,the morphological characteristics and karyotype of P.fulvidraco in Yuanshui River and Lishui River of Dongting Lake were analyzed.[Result] In three ratio traits including standard length/head length,standard length/caudal peduncle depth,head length/snout length,P.fulvidraco of Yuanshui River and Lishui River had significant differences(P0.05).However,the number and karyotype of their chromosomes were same.The chromosome number was 2n = 52,and the karyotype formula was 20M+12SM+10ST+10T.The number of chromosome arm was 84.[Conclusion] The research result had certain theoretical guidance significance for the protection and utilization of wild P.resource in Dongting Lake water system. 展开更多
关键词 Dongting Lake water system Yuanshui River and Lishui River P.fulvidraco Morphological characteristic KARYOTYPE
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Prediction of soil–water characteristic curve for Malan loess in Loess Plateau of China 被引量:11
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作者 LI Ping LI Tong-lu 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期432-447,共16页
To predict the soil-water characteristic curve(i.e.SWCC)of natural and remoulded Malan loess from soil physical properties,one-point methods for determining the SWCC that are much simpler than experimental methods are... To predict the soil-water characteristic curve(i.e.SWCC)of natural and remoulded Malan loess from soil physical properties,one-point methods for determining the SWCC that are much simpler than experimental methods are proposed.The predicted SWCC is presented in the form of the BRUTSAERT equation,in which the four model parameters can be estimated from soil physical properties using the best correlations obtained in the present study along with one measured data point.The proposed one-point methods are validated using the measured SWCC data reported in the literature.The results of validation studies suggest that the proposed one-point methods can provide reasonable prediction of the SWCC for natural and remoulded Malan loess.The measured data point should be within the transition zone;the measured suction is suggested between25to100kPa for natural loess,while between100to500kPa for remoulded loess. 展开更多
关键词 soil–water characteristic curve Malan loess natural loess remoulded loess one-point method physical properties
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An Object-based Approach for Two-level Gully Feature Mapping Using High-resolution DEM and Imagery: A Case Study on Hilly Loess Plateau Region, China 被引量:12
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作者 LIU Kai DING Hu +4 位作者 TANG Guoan ZHU A-Xing YANG Xin JIANG Sheng CAO Jianjun 《Chinese Geographical Science》 SCIE CSCD 2017年第3期415-430,共16页
Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) a... Gully feature mapping is an indispensable prerequisite for the motioning and control of gully erosion which is a widespread natural hazard. The increasing availability of high-resolution Digital Elevation Model(DEM) and remote sensing imagery, combined with developed object-based methods enables automatic gully feature mapping. But still few studies have specifically focused on gully feature mapping on different scales. In this study, an object-based approach to two-level gully feature mapping, including gully-affected areas and bank gullies, was developed and tested on 1-m DEM and Worldview-3 imagery of a catchment in the Chinese Loess Plateau. The methodology includes a sequence of data preparation, image segmentation, metric calculation, and random forest based classification. The results of the two-level mapping were based on a random forest model after investigating the effects of feature selection and class-imbalance problem. Results show that the segmentation strategy adopted in this paper which considers the topographic information and optimal parameter combination can improve the segmentation results. The distribution of the gully-affected area is closely related to topographic information, however, the spectral features are more dominant for bank gully mapping. The highest overall accuracy of the gully-affected area mapping was 93.06% with four topographic features. The highest overall accuracy of bank gully mapping is 78.5% when all features are adopted. The proposed approach is a creditable option for hierarchical mapping of gully feature information, which is suitable for the application in hily Loess Plateau region. 展开更多
关键词 object-based image analysis gully feature hierarchical mapping gully erosion Digital Elevation Model(DEM)
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Distribution patterns of chlorophyll a in spring and autumn in association with hydrological features in the southern Yellow Sea and northern East China Sea 被引量:4
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作者 张芳 李超伦 +2 位作者 孙松 吴玉霖 任敬萍 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第4期784-792,共9页
Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankt... Two field studies were conducted to measure pigments in the Southern Yellow Sea (SYS) and the northern East China Sea (NECS) in April (spring) and September (autumn) to evaluate the distribution pattern of phytoplankton stock (Chl a concentration) and the impact of hydrological features such as water mass,mixing and tidal front on these patterns.The results indicated that the Chl a concentration was 2.43±2.64 (Mean ± SD) mg m-3 in April (range,0.35 to 17.02 mg m-3) and 1.75±3.10 mg m-3 in September (from 0.07 to 36.54 mg m-3) in 2003.Additionally,four areas with higher Chl a concentrations were observed in the surface water in April,while two were observed in September,and these areas were located within or near the point at which different water masses converged (temperature front area).The distribution pattern of Chl a was generally consistent between onshore and offshore stations at different depths in April and September.Specifically,higher Chl a concentrations were observed along the coastal line in September,which consisted of a mixing area and a tidal front area,although the distributional pattern of Chl a concentrations varied along transects in April.The maximum Chl a concentration at each station was observed in the surface and subsurface layer (0-10 m) for onshore stations and the thermocline layer (10-30 m) for offshore stations in September,while the greatest concentrations were generally observed in surface and subsurface water (0-10 m) in April.The formation of the Chl a distributional pattern in the SYS and NECS and its relationship with possible influencing factors is also discussed.Although physical forces had a close relationship with Chl a distribution,more data are required to clearly and comprehensively elucidate the spatial pattern dynamics of Chl a in the SYS and NECS. 展开更多
关键词 FRONT MIXING Yellow Sea Cold Bottom Water Chl a distribution pattern
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Relocation of the Yellow River Estuary in 1855 AD Recorded in the Sediment Core from the Northern Yellow Sea 被引量:3
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作者 ZHOU Xin JIA Nan +2 位作者 CHENG Wenhan WANG Yuhong SUN Liguang 《Journal of Ocean University of China》 SCIE CAS 2013年第4期624-628,共5页
Relocation of the Yellow River estuary has significant impacts on not only terrestrial environment and human activities, but also sedimentary and ecological environments in coastal seas. The responses of regional geoc... Relocation of the Yellow River estuary has significant impacts on not only terrestrial environment and human activities, but also sedimentary and ecological environments in coastal seas. The responses of regional geochemical characteristics to the relocation event, however, have not been well studied. In the present study, we performed detailed geochemical elemental analyses of a sediment core from the northern Yellow Sea and studied their geochemical responses to the 1855AD relocation of the Yellow River estuary. The results show that TOC/TN, Co/A1203, Cr/A1203, Ni/A1203 and Se/A1203 ratios all decreased abruptly after 1855 AD, and similar decreases are observed in the sediments of the mud area southwest off the Cheju Island. These abrupt changes are very likely caused by the changes in source materials due to the relocation of the Yellow River estuary from the southern Yellow Sea to the Bohai Sea, which the corresponding decreasing trends caused by the changes in main source materials from those transported by the Liaohe River, the Haihe River and the Luanhe River to those by the Yellow River. Because the events have precise ages recorded in historical archives, these obvious changes in elemental geochemistry of sediments can be used to calibrate age models of related coastal sea sediments. 展开更多
关键词 relocation of the Yellow River estuary muddy sediments northern Yellow Sea elemental geochemistry
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Characterization and separation of pyrite from Abu Tartur black shale 被引量:6
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作者 Ibrahim S.S. El Kammar A.M. Guda A.M. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2015年第4期565-571,共7页
This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled i... This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite-rich black shale of the U. Cretaceous age, Sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/S and XRF techniques. Clay minerals, silt-sized quartz, calcite, and hematite were the main minerals associating pyr- ite (5.34g). Liberation behavior of the sample was about 80% below 5 μm. Sample processing was achieved through one-day soaking followed by classification using I inch Mozley hydro-cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using SB-40 Falcon Concentrator through a CCD statistical design prepared by Design-Expert 6.0 software proposed to opti- mize the separation process through a study for the effects of frequency (Hz) and water pressure (Psi) on both assay and recovery of the sulfur-rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% (21.24% pyrite) with overall recovery (50.01%) was obtained after two cleaning at the optimum conditions. 展开更多
关键词 Abu Tartur plateau Black shale PYRITE Falcon Concentrator
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Effect of Colored Sticky Cards on Non-target Insects 被引量:2
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作者 Zhen CHEN Yihang GE +1 位作者 Xia LIU Rongping KUANG 《Agricultural Science & Technology》 CAS 2015年第5期983-987,共5页
Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards wer... Field experiments to evaluate four different colored sticky cards for trapping non-target insects were conducted in an organic maize field in the Heinigou region of China. Yellow, blue, green, and red sticky cards were used to trap insects in the field. The total number of insects species caught was 54, with 3,862 individuals recorded. Over half of the specimens caught were non-target insects, including phytophagous insects, particularly dipteran species(including many mosquitoes)(50.3%), followed by target pests(37.0%), and beneficial insects(12.7%). Statistical analysis revealed a significant difference in attraction to target pests, non-target pests, and beneficial insects among treatment groups. The results showed that higher numbers of target pests(Myzus persicae Sulzer, Empoasca flavescens Fabricius, Nysius ericaecshinly Schilling) were caught on yellow sticky card traps compared with blue, green, or red sticky card traps, indicating that yellow was the best trap color for target pests, with green and blue being progressively less attractive. For non-target insects, including phytophagous insects, flies, and mosquitoes,higher numbers of were caught on blue sticky card traps compared with yellow,green, or red sticky card traps. Our study indicated that blue was the most attractive color for flies, especially for the housefly, Musca domestica Linnaeus. Our study also showed that most beneficial insects exhibited preferences to particular trap color characteristics: yellow was the most attractive color for parasitic wasps and lady beetles; blue was the most attractive color for hoverflies and honeybees. In contrast,green and red had no significant attraction to beneficial insects. 展开更多
关键词 Colored sticky cards Color trap Non-target insects Beneficial insects Natural enemies Conservation
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Distribution and characterizing sources of polycyclic aromatic hydrocarbons of surface water from Jialing River 被引量:3
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作者 许晓毅 蒋真玉 +5 位作者 王继行 朱虹 豆俊峰 H.D.Narres D.Hofmann E.Klumpp 《Journal of Central South University》 SCIE EI CAS 2012年第3期850-854,共5页
Sixteen priority polycyclic aromatic hydrocarbons(PAHs) in surface water samples were analyzed by gas chromatograph-mass spectrometer(GC-MS) to study their distribution and characterizing sources.The water samples wer... Sixteen priority polycyclic aromatic hydrocarbons(PAHs) in surface water samples were analyzed by gas chromatograph-mass spectrometer(GC-MS) to study their distribution and characterizing sources.The water samples were collected from five sites(J1-J5) in the Jialing River of Chongqing downtown area from September 2009 to August 2010.The results demonstrate that the concentration of total PAHs in three samples upstream are relatively higher than those in other two sites downstream,with average concentration of total PAHs for each site ranging from 811.5 ng/L to 1585.8 ng/L.The 2,3 and 4-ring PAHs for sampling stations account for 13.0%,56.6% and 28.6%,respectively,in total PAHs.There are obvious tendencies of seasonal change for PAHs concentration in surface water.The PAHs concentration in April of wet season is 1 301.6 ng/L,which is 1.3 times the lowest amount of total PAHs in August of flood season.Ratios of specific PAH compounds were used to characterize the possible pollution sources.Experimental results indicate that the PAHs in surface water samples are primarily from pyrolytic PAHs because of factories along these sites,while the direct leakage of petroleum products may be significant for two sites,Jiahua Bridge(J4) and Huanghuayuan Bridge(J5),because of the wharf boat nearby. 展开更多
关键词 polycyclic aromatic hydrocarbons source and distribution surface water Jialing River
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Purification and characterization of vitellin in mature ovary of marine crab Charybdis japonica 被引量:1
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作者 谢松 郭成秀 +1 位作者 柳峰松 梁晓晖 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期162-165,共4页
Vitellin of mature female marine crab Charybdis japonica was purified by high-performance liquid chromatography (HPLC, DEAE-cellulose-16 anion exchange column). The apparent molecular mass of the vitellin is 546 ku ba... Vitellin of mature female marine crab Charybdis japonica was purified by high-performance liquid chromatography (HPLC, DEAE-cellulose-16 anion exchange column). The apparent molecular mass of the vitellin is 546 ku based on the data of native-PAGE. Under denatured condition (SDS-PAGE), it was found that vitellin was composed of four polypeptides each at 120, 100, 65, and 55 ku. One disulfide bond was detected in the binding of polypeptide subunits. The purified vitellin, contained 4.47% phosphor and 10.6% polysaccharides, and was identified as glyco-lipo-carotenoprotein, according to the PAGE staining data. The purified vitellin can be used as antigen to raise polyclonal antisera in further application. 展开更多
关键词 Charybdis japonica VITELLIN PURIFICATION characterization
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Heavy Metal Runoff in Relation to Soil Characteristics 被引量:16
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作者 ZHAO XIULAN, QING CHANGLE and WEI SHIQIANG College Of Resources and Environmental Science, Southwest Agricultural University, Chongqing 400716 (china) 《Pedosphere》 SCIE CAS CSCD 2001年第2期137-142,共6页
Cu, Zn, Pb and Hg runoff from yellow limestone soil and purple soils and the relationships between the mobility of the heavy metals and the soil characteristics were studied in laboratory using a rainfall simulator. T... Cu, Zn, Pb and Hg runoff from yellow limestone soil and purple soils and the relationships between the mobility of the heavy metals and the soil characteristics were studied in laboratory using a rainfall simulator. The results showed that the concentrations of soluble Zn in surface runoff were significantly negatively correlated with the contents of <0.002 mm particles and CEC of the soils, indicating that Zn was mostly adsorbed by clays in the soils. The contents of Cu and Hg in surface runoff were positively related to their contents in the soils. The amounts of Cu, Zn, Pb and Hg removed by surface runoff were influenced by the amounts of soil and water losses and their contents in the soils, and were closely related to the contents of soil particles 1-0.02 mm in size. 展开更多
关键词 heavy metal MOBILITY soil characteristics surface runoff
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Geochemistry of Trace and Rare Earth Elements in Red Soils from the Dongting Lake Area and Its Environmental Significance 被引量:7
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作者 MAO Long-Jiang MO Duo-Wen +1 位作者 YANG Jing-Hong SHI Chen-Xi 《Pedosphere》 SCIE CAS CSCD 2009年第5期615-622,共8页
Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red soils.The results show... Trace element(TE) and rare earth element(REE) contents in red soils from the Dongting Lake area of China were determined to understanding the provenance and weathering characteristics of the red soils.The results showed similar REE distribution patterns among red soils from the Dongting Lake area,Xiashu loess from Zhenjiang,loess and Pliocene red soil from the Loess Plateau.These patterns implied a similar provenance from dust-storms,except for red soil R5 which formed by bedrock weathering and had significant light REE(LREE) enrichment and heavy REE(HREE) depletion due to longer weathering periods and higher intensity of weathering.Trace element,especially the Rb/Sr and Li/Ba ratios,and REE,especially the LREE/HREE ratio and δEu could trace weathering intensity.Higher Rb/Sr,Li/Ba,and LREE/HREE ratios and negative Eu anomalies were present in the red soils from the Dongting Lake area.The weathering intensity was in the decreasing order of R5 in the Dongting Lake area > red soils from the Dongting Lake area(including reticulate red soil,weak reticulate red soil,and homogeneous red soil formed by dust storms) > Xiashu loess from Zhenjiang > loess-paleosol and Pliocene red soil from the Loess Plateau.Variations in the TE and REE contents of soil could be effectively used to study the provenance and the weathering intensity. 展开更多
关键词 Hunan Province PROVENANCE sedimentary processes weathering intensity
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Characteristics of Vertical Distributions of Fatty Acids in Surface Sediments of the Yellow Sea and East China Sea
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作者 LOPES Evanildo O. WANG Mengqi +2 位作者 CHEN Ying YANG Guipeng DING Haibing 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1123-1134,共12页
Fatty acids(FAs) in sediment collected from three different stations in the Yellow Sea and the East China Sea were analyzed for their distributions and to determine evidence of harmful algal blooms in the sediment cor... Fatty acids(FAs) in sediment collected from three different stations in the Yellow Sea and the East China Sea were analyzed for their distributions and to determine evidence of harmful algal blooms in the sediment core.Less diverse FAs were found in the Yellow Sea(YS) station,whereas in the two stations of the East China Sea(ECS) the FAs were more diverse.Concentrations of some FA species in the two ECS stations displayed an occasional surge in their vertical profile.The highest concentration of FAs was found in the surface layer of station QT3(43.28 μg g^(-1)).Monounsaturated FAs were more susceptible to degradation compared to their saturated counterparts,and changes of 16:0,18:2 and 20:5 accounted for the most variability in total concentrations of FAs as those species made up most of the quantified FAs.The origins of the major fraction of FAs were attributed to autotrophic sources,and bacterial FAs accounted for only a small fraction of the total FAs in the region.Nutrient availability was a possible regulating factor controlling bacteria abundances in marine sediments in the ECS and the YS.A principal component analysis(PCA) was applied to analyze the FA dataset and to reveal the principal environmental factors that control the composition of FAs in the sediments.PC2,which explains 15% of the variance,was estimated to reflect the diagenetic effects on the FA compositional changes in sediments influenced by bacterial degradation. 展开更多
关键词 fatty acids Yellow Sea East China Sea SEDIMENTS DIAGENESIS
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Hepatic venous outflow obstruction:Three similar syndromes 被引量:28
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作者 Ulas Darda Bayraktar Soley Seren Yusuf Bayraktar 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第13期1912-1927,共16页
Our goal is to provide a detailed review of veno- occlusive disease (VOD), Budd-Chiari syndrome (BCS), and congestive hepatopathy (CH), all of which results in hepatic venous outflow obstruction. This is the first art... Our goal is to provide a detailed review of veno- occlusive disease (VOD), Budd-Chiari syndrome (BCS), and congestive hepatopathy (CH), all of which results in hepatic venous outflow obstruction. This is the first article in which all three syndromes have been reviewed, enabling the reader to compare the characteristics of these disorders. The histological findings in VOD, BCS, and CH are almost identical: sinusoidal congestion and cell necrosis mostly in perivenular areas of hepatic acini which eventually leads to bridging fibrosis between adjacent central veins. Tender hepatomegaly with jaundice and ascites is common to all three conditions. However, the clinical presentation depends mostly on the extent and rapidity of the outflow obstruction. Although the etiology and treatment are completely different in VOD, BCS, and CH; the similarities in clinical manifestations and liver histology may suggest a common mechanism of hepatic injury and adaptation in response to increased sinusoidal pressure. 展开更多
关键词 Veno-occlusive disease Sinusoidal obstru-ction syndrome Budd-Chiari syndrome Congestivehepatopathy
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Geological significance of componential characteristics of pyrite from Shibaqinghao gold deposit in central Inner Mongolia, China
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作者 Yihong Liang Hongying Zhang Yanhua Ma 《Global Geology》 2006年第1期54-59,共6页
There are two types of gold ore in Shibaqinghao gold deposit, mylonite ore and quartz vein ore. Pyrite accompanying with native gold in mylonite ore has Fe from 43.66 to 45.32 wt 96 and S from 52.64 to 53.55 wt%. It i... There are two types of gold ore in Shibaqinghao gold deposit, mylonite ore and quartz vein ore. Pyrite accompanying with native gold in mylonite ore has Fe from 43.66 to 45.32 wt 96 and S from 52.64 to 53.55 wt%. It is clear that this kind of pyrite is poor in both sulphur and iron. That means that the mylonite oremay be related to metamorphic water. Pyrite in the quartz vein ore has Fe from 44.38 to 45.30 wt% and S from 53.08 to 54.00 wt%. It means that this kind of pyrite is poor in iron but rich in sulphur, while the quartz vein ore may be related to magma water. 展开更多
关键词 gold deposit PYRITE componential characteristics
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Sedimentary Characteristics of the Second Marine Layer During the Late Marine Isotope Stage 3 in Southern Yellow Sea and Their Response to the East Asian Monsoon
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作者 ZHANG Yang LI Guangxue +8 位作者 GUO Hongzhou LIU Yong WANG Haoyin XU Jishang DING Dong QIAO Lulu MA Yanyan WANG Liyan LI Qian 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1103-1113,共11页
We use the particle size of sediments in core YS01A to study the sedimentary environment of the mud deposit in the central South Yellow Sea of China during late Marine Isotope Stages 3 (MIS3; 40.5 kyr-31.3 kyr). In ... We use the particle size of sediments in core YS01A to study the sedimentary environment of the mud deposit in the central South Yellow Sea of China during late Marine Isotope Stages 3 (MIS3; 40.5 kyr-31.3 kyr). In addition, the East Asian Monsoon and its relationship with the North Atlantic Ocean climate change are discussed based on the sensitive grain-size calculation and the spectrum analysis. The results show that during late MIS3, the muddy area in the central South Yellow Sea experienced the evolution of coastal facies, shallow marine facies, coastal facies, and continental facies, with weak hydrodynamic conditions. Compared with other climate indicators, we found that there were many century to millennium-scale climate signals documented in the muddy area sediments in the central South Yellow Sea. According to our particle size results, three strong winter monsoon events occurred at 37.6kyr, 35.6kyr and 32.2kyr. The East Asian Winter Monsoon records in core YS01A are consistent with the Greenland ice core and the Hulu cave stalagmite 8180. The millennial and centennial scale cycles, which are 55 yr, 72 yr, 115 yr, 262 yr respectively, correspond to solar activity cycles, while the 1049 yr and 2941 yr cycles correspond to the Dansgaard-Oeschger cycles. These cycles indicate that the paleoclimate evolution of the area was controlled by the solar activities, with the high-latitude driving thermohaline circulation as the main energy conveyor belt, followed by the sea-air-land amplification of the winter monsoon variation in the central Yellow Sea in the late MIS3. 展开更多
关键词 sedimentary environment central South Yellow Sea East Asian Monsoon sensitive grade calculation thermohaline circulation
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Local records of long-term dynamics of bamboo gregarious flowering in northern Laos and regional synchronicity of Dendrocalamus membranaceus in two flowering sites 被引量:2
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作者 HIROTA Isao 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1058-1064,共7页
Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and d... Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and death has a major impact on forest vegetation. Although the small-scale dynamics of this process have become clearer in recent years, the history, geographical scale and synchronicity of bamboo flowering over broad areas remains unknown. This study focused on the flowering history of six bamboo species, Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus hamiltonii, Dendrocalamus membranaceus, Indosasa sinica and Oxytenanthera parvifolia, over 40 years across a broad area of northern Laos. We also examined the synchronicity of flowering in D. membranaceus. We visited 49 villages in northern Laos and surveyed knowledgeable inhabitants about bamboo flowering history. The timing, scale and synchronicity of gregarious flowering varied among species. D. hamiltonii and D. membranaceus showed higher flowering synchronicity than other species. All the species except I. sinica had both sporadic and gregarious flowering traits, and showed conspicuous variability in their flowering scale. The flowering bamboo population at two gregarious flowering sites for D. membranaceus was surveyed. While thisspecies had the highest synchronicity in this study, its synchronicity was lower than other species in previous studies worldwide. We found that the gregarious flowering of bamboos in northern Laos over the last 40 years showed lower synchronicity than bamboo flowering reported in other areas of the world. The historical dynamics and scale of bamboo flowering must be further clarified to understand the vegetation composition of this area. 展开更多
关键词 Fallow forest Sporadic flowering Shifting cultivation Synchronicity Southeast Asia
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Clinical features and risk factors of acute hepatitis E with severe jaundice 被引量:11
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作者 Bin Xu Hai-Bin Yu +4 位作者 Wei Hui Jia-Li He Lin-Lin Wei Zheng Wang Xin-Hui Guo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第48期7279-7284,共6页
AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We e... AIM:To compares the clinical features of patients infected with hepatitis E virus(HEV) with or without severe jaundice.In addition,the risk factors for HEV infection with severe jaundice were investigated.METHODS:We enrolled 235 patients with HEV into a cross-sectional study using multi-stage sampling to select the study group.Patients with possible acute hepatitis E showing elevated liver enzyme levels were screened for HEV infection using serologic and molecular tools.HEV infection was documented by HEV antibodies and by the detection of HEV-RNA in serum.We used χ2 analysis,Fisher's exact test,and Student's t test where appropriate in this study.Significant predictors in the univariate analysis were then included in a forward,stepwise multiple logistic regression model.RESULTS:No significant differences in symptoms,alanine aminotransferase,aspartate aminotransferase,al-kaline phosphatase,or hepatitis B virus surface antigen between the two groups were observed.HEV infected patients with severe jaundice had significantly lower peak serum levels of γ-glutamyl-transpeptidase(GGT)(median:170.31 U/L vs 237.96 U/L,P = 0.007),significantly lower ALB levels(33.84 g/L vs 36.89 g/L,P = 0.000),significantly lower acetylcholine esterase(CHE) levels(4500.93 U/L vs 5815.28 U/L,P = 0.000) and significantly higher total bile acid(TBA) levels(275.56 μmol/L vs 147.03 μmol/L,P = 0.000) than those without severe jaundice.The median of the lowest point time tended to be lower in patients with severe jaundice(81.64% vs 96.12%,P = 0.000).HEV infected patients with severe jaundice had a significantly higher viral load(median:134 vs 112,P = 0.025) than those without severe jaundice.HEV infected patients with severe jaundice showed a trend toward longer median hospital stay(38.17 d vs 18.36 d,P = 0.073).Multivariate logistic regression indicated that there were significant differences in age,sex,viral load,GGT,albumin,TBA,CHE,prothrombin index,alcohol overconsumption,and duration of admission between patients infected with acute hepatitis E with and without severe jaundice.CONCLUSION:Acute hepatitis E patients may naturally present with severe jaundice. 展开更多
关键词 Hepatitis E virus Acute hepatitis E Clinical features Severe jaundice Risk factor
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Effect of Root Architecture on Structural Stability and Erodibility of Topsoils during Concentrated Flow in Hilly Loess Plateau 被引量:13
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作者 LI Qiang LIU Guobin +2 位作者 ZHANG Zheng TUO Dengfeng XU Mingxiang 《Chinese Geographical Science》 SCIE CSCD 2015年第6期757-764,共8页
Traditional vegetation techniques for the control of concentrated flow erosion are widely recognized, whereas only a few studies have experimentally investigated the impacts of belowground roots on the erodibility of ... Traditional vegetation techniques for the control of concentrated flow erosion are widely recognized, whereas only a few studies have experimentally investigated the impacts of belowground roots on the erodibility of topsoils in semi-arid areas. To quantify the effects of root architectures on soil erodibility and its relevant structural properties, simulated flow experiments were conducted at six-week intervals from 18 July to 20 October in 2012 in the hilly Loess Plateau. Five treatments were: 1) bare(control), 2) purple alfalfa(Medicago sativa), representing tap roots(T), 3) switchgrass(Panicum virgatum), representing fibrous roots(F), 4) purple alfalfa and switchgrass, representing both tap and fibrous roots(T + F), and 5) natural recovery(N). For each treatment, soil structural properties and root characteristics were measured at an interval of six weeks. Soil anti-scouribility was calculated. Results showed that grass planting slightly reduced soil bulk density, but increased soil aggregate content by 19.1%, 10.6%, 28.5%, and 41.2% in the treatments T, F, T + F, and N, respectively. Soil shear strength(cohesion and angle of internal friction(φ)) significantly increased after the grass was planted. As roots grew, soil cohesion increased by 115.2%–135.5%, while soil disintegration rate decreased by 39.0%–58.1% in the 21 th week compared with the recorded value in the 9th week. Meanwhile, root density and root surface area density increased by 64.0%–104.7% and 75.9%–157.1%, respectively. No significant differences in soil anti-scouribility were observed between the treatments of T and F or of T + F and N, but the treatments of T + F and N performed more effectively than T or F treatment alone in retarding concentrated flow. Soil aggregation and root surface-area density explained the observed soil anti-scouribility during concentrated flow well for the different treatments. This result proved that the restoration of natural vegetation might be the most appropriate strategy in soil reinforcement in the hilly Loess Plateau. 展开更多
关键词 fibrous roots tap roots root density soil structural properties soil anti-scouribility hilly Loess Plateau China
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Inversion and Prediction of Consolidation Settlement Characteristics of the Fluvial Sediments Based on Void Ratio Variation in the Northern Modern Yellow River Subaqueous Delta, China 被引量:1
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作者 LIU Xiao LIU Jie FENG Xiuli 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期545-554,共10页
The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacte... The modern Yellow River delta is formed near the estuary of the Yellow River with the characteristics of short formation time, efficient sedimentation rate and loose structure which make sediments prone to be compacted and consolidate under the geostatic stress and overburden stress. It is one of the key areas with land subsidence disasters in China, bringing a series of safety hazards to production and living. Based on the data of massive surface cores and ten drill holes ranging from 12 to 40 m obtained from the northern modern Yellow River subaqueous delta, the inversion method suitable for the calculation of consolidation settlement characteristics of the modern Yellow River subaqueous delta is discussed, and the consolidation settlement characteristics of the delta sediments are inversed and predicted in this paper. The actual void ratio of the delta sediments at the depth from 3 to 15 m shows a significant power function relationship with the depth, while the void ratio of the sediments below 15 m changes little with depth. The pre-consolidation settlement(from deposition to sampling) of the delta sediments is between 0.91 and 1.96 m, while the consolidation settlement of unit depth is between 9.6 and 14.0 cm m^(-1). The post-consolidation settlement(from sampling to stable) of the subaqueous delta sediments is between 0.65 and 1.56 m in the later stage, and the consolidation settlement of unit depth is between 7.6 and 13.1 cm m^(-1) under the overburden stress. The delta sediments with a buried depth of 3 to 7 m contribute the most to the possible consolidation settlement in the later stage. 展开更多
关键词 consolidation settlement void ratio sediment grain size northern modern Yellow River subaqueous delta
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