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| 1 | Effect of Reclamation Time and Land Use on Soil Properties in Changjiang River Estuary,China显示文摘The objective of this study is to analyze soil physical and chemical properties,soil comprehensive functions and impact factors after different years of reclamation.Based on the survey data taken from 216 soil sampling points in the Fengxian Reclamation Area of the Changjiang (Yangtze) River Estuary,China in April 2009 and remotely sensed TM data in 2006,while by virtue of multivariate analysis of variance (MANOVA),geo-statistical analysis (GA),prin-cipal component analysis (PCA) and canonical correspondence analysis (CCA),it was concluded that:1) With the in-crease in reclamation time,soil moisture,soil salinity,soil electric conductivity and soil particle size tended to decline,yet soil organic matter tended to increase.Soil available phosphorous tended to increase in the early reclamation period,yet it tended to decline after about 49 years of reclamation.Soil nitrate nitrogen,soil ammonia nitrogen and pH changed slightly in different reclamation years.Soil physical and chemical properties reached a steady state after about 30 years of reclamation.2) According to the results of PCA analysis,the weighted value (0.97 in total) that represents soil nutrient factors (soil nitrate nitrogen,soil organic matter,soil available phosphorous,soil ammonia nitrogen,pH and soil particle size) were higher than the weighted value (0.48 in total) of soil limiting factors (soil salinity,soil elec-tric conductivity and soil moisture).The higher the F value is,the better the soil quality is.3) Different land use types play different roles in the soil function maturity process,with farmlands providing the best contribution.4) Soil physi-cal and chemical properties in the reclamation area were mainly influenced by reclamation time,and then by land use types.The correlation (0.1905) of the composite index of soil function (F) with reclamation time was greater than that with land use types (-0.1161). | SUN Yongguang LI Xiuzhen ülo MANDER HE Yanlong JIA Yue MA Zhigang GUO Wenyong XIN Zaijun | 2011 | Chinese Geographical Science2011，21，4： | 17 |
| 2 | Seasonal dynamics of water bloom-forming Microcystis morphospecies and the associated extracellular microcystin concentrations in large,shallow,eutrophic Dianchi Lake显示文摘The increasing occurrence of Microcystis blooms is of great concern to public health and ecosystem due to the potential hepatotoxic microcystins(MCs)produced by these colonial cyanobacteria.In order to interpret the relationships between variations of Microcystis morphospecies and extracellular MC concentrations,the seasonal dynamics of phytoplankton community composition,MC concentrations,and environmental parameters were monitored monthly from August,2009 to July,2010.The results indicated that Microcystis dominated total phytoplankton abundance from May to December(96%–99%of total biovolume),with toxic Microcystis viridis and non-toxic Microcystis wesenbergii dominating after July(constituting 65%–95%of the Microcystis population),followed by M.viridis as the sole dominant species from November to January(49%–93%).Correlation analysis revealed that water temperature and nutrient were the most important variables accounting for the occurrence of M.wesenbergii,while the dominance of M.viridis was related with nitrite and nitrate.The relatively low content of MCs was explained by the association with a large proportion of M.viridis and M.wesenbergii,small colony size of Microcystis populations,and low water temperature,pH and dissolved oxygen.The extracellular MC(mean of 0.5±0.2μg/L)of water samples analyzed by enzyme-linked immunosorbent assay(ELISA)demonstrated the low concentrations of MC in Dianchi Lake which implied the low potential risk for human health in the basin.The survey provides the first whole lake study of the occurrence and seasonal variability of Microcystis population and extracellular MCs that are of particular interest for water quality monitoring and management. | Yanlong Wu Lin Li Nanqin Gan Lingling Zheng Haiyan Ma Kun Shan Jin Liu Bangding Xiao Lirong Song | 2014 | Journal of Environmental Sciences2014，26，9： | 12 |
| 3 | Undrained shear strength evaluation for hydrate-bearing sediment overlying strata in the Shenhu area, northern South China Sea显示文摘The undrained shear strength of shallow strata is a critical parameter for safety design in deep-water operations.In situ piezocone penetration tests(CPTU) and laboratory experiments are performed at Site W18-19 in the Shenhu area, northern South China Sea, where China's first marine hydrate exploitation operation is due to be located. The validation of the undrained shear strength prediction model based on CPTU parameters. Different laboratory tests, including pocket penetrometer, torvane, miniature vane and unconsolidated undrained triaxial tests, are employed to solve empirical cone coefficients by statistical and mathematical methods. Finally, an optimized model is proposed to describe the longitudinal distribution of undrained shear strength in calcareous clay strata in the Shenhu area. Research results reveal that average empirical cone coefficients based on total cone resistance, effective resistance, and excess-pore pressure are 13.8, 4.2 and 14.4, respectively. The undrained shear strength prediction model shows a good fit with the laboratory results only within specific intervals based on their compaction degree and gas-bearing conditions. The optimized prediction model in piecewise function format can be used to describe the longitudinal distribution of the undrained shear strength for calcareous clay within all depth intervals from the mud-line to the upper boundary of hydrate-bearing sediments(HBS). The optimized prediction result indicates that the effective cone resistance model is suitable for very soft to firm calcareous clays,the excess-pore pressure model can depict the undrained shear strength for firm to very stiff but gas-free clays,while the total cone resistance model is advantageous for evaluating the undrained shear strength for very stiff and gassy clays. The optimized model in piecewise function format can considerably improve the adaptability of empirical models for calcareous clay in the Shenhu area. These results are significant for safety evaluations of proposed hydrate exploitation projects. | Yanlong Li Gaowei Hu Nengyou Wu Changling Liu Qiang Chen Chen'an Li | 2019 | Acta Oceanologica Sinica2019，38，3： | 12 |
| 4 | Modeling the distribution of Populus euphratica in the Heihe River Basin, an inland river basin in an arid region of China显示文摘Populus euphratica is a dominant tree species in riparian Tugai forests and forms a natural barrier that maintains the stability of local oases in arid inland river basins. Despite being critical information for local environmental protection and recovery, establishing the specific spatial distribution of P. euphratica has rarely been attempted via precise and reliable species distribution models in such areas. In this research, the potential geographic distribution of P. euphratica in the Heihe River Basin was simulated with MaxEnt software based on species occurrence data and 29 environmental variables. The result showed that in the Heihe River Basin, 820 km^2 of land primarily distributed along the banks of the lower reaches of the river is a suitable habitat for P. euphratica. We built other MaxEnt models based on different environmental variables and another eight models employing different mathematical algorithms based on the same 29 environmental variables to demonstrate the superiority of this method.MaxEnt based on 29 environmental variables performed the best among these models, as it precisely described the essential characteristics of the distribution of P. euphratica forest land. This study verified that MaxEnt can serve as an effective tool for species distribution in extremely arid regions with sufficient and reliable environmental variables. The results suggest that there may be a larger area of P. euphratica forest distribution in the study area and that ecological conservation and management of P.euphratica should prioritize suitable habitat. This research provides valuable insights for the conservation and management of degraded P. euphratica riparian forests. | Yanlong GUO Xin LI Zefang ZHAO Haiyan WEI | 2018 | Science China Earth Sciences2018，61，11： | 12 |
| 5 | Mechanical Properties of Methane Hydrate-Bearing Interlayered Sediments显示文摘The complex distribution of gas hydrate in sediments makes understanding the mechanical properties of hydrate-bearing sediments a challenging task.The mechanical behaviors of hydrate-bearing interlayered sediments are still poorly known.A series of triaxial shearing tests were conducted to investigate the strength parameters and deformation properties of methane hydrate-bearing interlayered sediments at the effective pressure of 1 MPa.The results indicate that the stress-strain curves of hydrate-bearing interlayered sediments are significantly different from that of hydrate-bearing sediments.The peak strength,Young's modulus,initial yielding modulus,and failure mode are deeply affected by the methane hydrate distribution.The failure behaviors and mechanism of strain softening and hardening patterns of the interlayered specimens are more complicated than those of the integrated specimens.This study compares the different mechanical behaviors between integrated and interlayered specimens containing gas hydrate,which can serve as a reference for the prediction and analysis of the deformation behaviors of natural gas hydrate reservoirs. | DONG Lin LI Yanlong LIU Changling LIAO Hualin CHEN Guoqi CHEN Qiang LIU Lele HU Gaowei | 2019 | Journal of Ocean University of China2019，18，6： | 11 |
| 6 | High-performance silicon−graphene hybrid plasmonic waveguide photodetectors beyond 1.55μm显示文摘Graphene has attracted much attention for the realization of high-speed photodetection for silicon photonics over a wide wavelength range.However,the reported fast graphene photodetectors mainly operate in the 1.55μm wavelength band.In this work,we propose and realize high-performance waveguide photodetectors based on bolometric/photoconductive effects by introducing an ultrathin wide silicon−graphene hybrid plasmonic waveguide,which enables efficient light absorption in graphene at 1.55μm and beyond.When operating at 2μm,the present photodetector has a responsivity of ~70 mA/W and a setup-limited 3 dB bandwidth of >20 GHz.When operating at 1.55μm,the present photodetector also works very well with a broad 3 dB bandwidth of >40 GHz(setup-limited)and a high responsivity of ~0.4 A/W even with a low bias voltage of−0.3 V.This work paves the way for achieving highresponsivity and high-speed silicon-graphene waveguide photodetection in the near/mid-infrared ranges,which has applications in optical communications,nonlinear photonics,and on-chip sensing. | Jingshu Guo Jiang Li Chaoyue Liu Yanlong Yin Wenhui Wang Zhenhua Ni Zhilei Fu Hui Yu Yang Xu Yaocheng Shi Yungui Ma Shiming Gao Limin Tong Daoxin Dai | 2020 | Light(Science & Applications)2020，9，1： | 10 |
| 7 | Remarkable anisotropic phonon response in uniaxially strained few-layer black phosphorus显示文摘黑磷(BP ) 是一个好候选人因为学习紧张在 graphene 和转变金属 dichalcogenides 以外在 twodimensional (2D ) 上完成材料。这因为它支撑高紧张和源于它的唯一的皱起的结构的显著地各向异性的机械性质的特别能力。我们这里调查格子的依赖在由在原处做作的拉曼的单轴地做作的很少层 BP 的结晶的取向上的震动的频率光谱学。out-of-plane A 1 而, g 模式对沿着近扶手椅的方向的单轴的紧张敏感在里面飞机 B 2g 和 A 2 g 模式是敏感的在近之字形的方向拉紧。为使用离开这些方向的单轴的种类,所有三个声子模式是线性地 redshifted。我们的试验性的观察被对 BP 的结构的性质的单轴的张力的紧张的各向异性的影响用密度解释功能的理论。这研究表明由单轴的紧张的在 BP 的在里面飞机和 out-of-plane 声子模式的选择调节的可能性并且使紧张工程成为一条有希望的大街为广泛地 modulating 2D 材料的光、机械的性质。 | Yanlong Wang Chunxiao Cong Ruixiang Fei Weihuang Yang Yu Chen Bingchen Cao Li Yang Ting Yu | 2015 | Nano Research2015，8，12： | 9 |
| 8 | Secondary biogenic coalbed gas in some coal fields of China显示文摘The secondary biogenic coalbed gas, a new genetic and energy source type of coalbed gas in China, has been found in Xinji, Liyazhuang and Enhong areas. The essential characteristics of this type of gas are: (i) the major component of the gas is methane, with C1/C1-5 value higher than 0.99, indicating that the gas is part of dry gas; (ii) theδ13C1 value is in the range of -61.7‰to -47.9‰, mostly lower than -55‰, which is much lower than the estimatedδ13C1 value of thermogenic methane according to the thermal evolution degree of the coal rocks (with R0 value from 0.87% to 1.43%), showing the characteristics of the secondary biogenic gas; (iii) theδ5D value of methane ranges from -244‰to -196‰; (iv)δ13C 2 value ranges from -26.7‰to -15.9‰andδ13C 3 value ranges from -10.8‰to -25.3‰, indicating that the heavier hydrocarbons have a thermogenic origin; (v) the content of CO2 is very low, andδ13CCO2 value changes greatly, reflecting a characteristic of secondary change; (vi)δ15N2 value ranges mainly from -1‰to +1‰, indicating N2 derived significantly from air. The negative linear correlation between the contents of N2 and CH4 reflects the activity of bacteria bearing surface water infiltrating into coal beds. The comprehensive tracing indices show that the coalbed gas in the studied areas is the mixed gas of primarily secondary biogenic gas and a part of remnant thermogenic gas. The uplift of coal beds and the development of faults in the studied areas create favorable conditions for the formation of the secondary biogenic gas. | TAO Mingxin WANG Wanchun XIE Guangxin LI Jinying WANG Yanlong ZHANG Xiaojun ZHANG Hong SHI Baoguang GAO Bo | 2005 | Chinese Science Bulletin2005，50，S1： | 8 |
| 9 | Corrosion behavior of Mg-Y alloy in NaCl aqueous solution | Xin Zhang a,b,c,Kui Zhang a,Xia Deng a,Hongwei Li b,c,Yongjun Li a,Minglong Ma a,Ning Li b,c,Yanlong Wang b,c a State Key Laboratory for Fabrication and Processing of Nonferrous Metals,Beijing General Research Institute for Nonferrous Metals,Beijing 100088,China b Beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,Beijing 100072,China c Center of Technology,Beijing North Vehicle Group Corporation,Beijing 100072,China | 2012 | Progress in Natural Science:Materials International2012，22，2： | 7 |
| 10 | Growth factor regulatory system:a new system for not truly recognized organisms显示文摘Growth,development,aging,and disease occurrence in organisms,especially animals or Homo sapiens,are regulated by different regulatory systems in vivo.The nervous,endocrine,metabolic,and immune systems are the traditional biological systems essential for the growth,development,and metabolism of the body.These systems maintain a balance and precisely biologically regulate every aspect of life activities under normal circumstances.However,in abnormal situations,owing to endogenous or exogenous attack,these regulatory systems result in dysfunction,subsequently leading to illness or injury(Muggianu et al.,2018).In the classical neuroendocrine regulatory system,Cushing’s syndrome is defined as a series of abnormal clinical symptoms with chronic overproduction of glucocorticoids in the adrenal cortex.Its clinical manifestations are“moon face”and“buffalo hump,”involving blood circulation,bone metabolism,and gonadal function,among others.In addition,severe trauma or burn leads to an imbalanced immune regulatory system,resulting in excessive inflammatory reactions and sepsis.Thus,an independent or cooperative regulation of multiple regulatory systems is critical in maintaining the body’s homeostasis,healthy development,and growth. | Jian Xiao Zhuofeng Lin Hua Qin Zhilong Zheng Fanghua Gong Yanlong Liu Xiaokun Li Xiaobing Fu | 2020 | Science China(Life Sciences)2020，63，3： | 5 |
| 11 | Structure insights into mechanisms of ATP hydrolysis and the activation of human heat-shock protein 90显示文摘分子的女伴热吃惊蛋白质 90 的激活(Hsp90 ) 依赖于 ATP 绑定和水解作用,它发生在蛋白质的 N 终端域。这里,我们与 ATP 和 ATP 类似物在土著人并且在建筑群决定了人的 Hsp90 的 N 终端领域的三水晶结构,提供由 Hsp90 的 ATP 水解作用的催化机制的一个清楚的看法。另外, ATP 的绑定导致 N 终端领域是能被用来部分解释 Hsp90 的孤立的 N 终端领域为什么举办很弱的 ATP hydrolytic 活动的一个中间的状态。 | Jian Li Lihua Sun Chunyan Xu Feng Yu Huan Zhou Yanlong Zhao Jian Zhang Jianhua Cai Cheney Mao Lin Tang Yechun Xu Jianhua He | 2012 | Acta Biochimica et Biophysica Sinica2012，44，4： | 5 |
| 12 | Sliding Mode Control with Perturbation Estimation and Hysteresis Compensator Based on Bouc-Wen Model in Tackling Fast-Varying Sinusoidal Position Control of a Piezoelectric Actuator显示文摘In this paper,a sliding mode control with perturbation estimation(SMCPE) coupled with an inverse hysteresis compensator is proposed for the motion tracking control of a microposition system with piezoelectric actuation.The inverse hysteresis compensator is employed to cancel the hysteresis nonlinearity,thus reducing the nonlinear system to a linear system with an inversion error.Then,a SMCPE controller is adopted to deal with all the unmodeled dynamics and disturbances,aiming at improving the dynamic performance and the robustness of system.An experiment of a piezoelectric actuator is presented to demonstrate the feasibility and effectiveness of the proposed control scheme.The result shows that for a fast-rate control input,the proposed method is capable of leading to a good performance of system behavior. | GAN Minggang QIAO Zhi LI Yanlong | 2016 | Journal of Systems Science & Complexity2016，29，2： | 5 |
| 13 | Coherent optical adaptive technique improves the spatial resolution of STED microscopy in thick samples显示文摘Stimulated emission depletion(STED) microscopy is one of far-field optical microscopy techniques that can provide sub-diffraction spatial resolution. The spatial resolution of the STED microscopy is determined by the specially engineered beam profile of the depletion beam and its power. However, the beam profile of the depletion beam may be distorted due to aberrations of optical systems and inhomogeneity of a specimen's optical properties, resulting in a compromised spatial resolution. The situation gets deteriorated when thick samples are imaged. In the worst case, the severe distortion of the depletion beam profile may cause complete loss of the superresolution effect no matter how much depletion power is applied to specimens. Previously several adaptive optics approaches have been explored to compensate aberrations of systems and specimens. However, it is difficult to correct the complicated high-order optical aberrations of specimens. In this report, we demonstrate that the complicated distorted wavefront from a thick phantom sample can be measured by using the coherent optical adaptive technique. The full correction can effectively maintain and improve spatial resolution in imaging thick samples. | WEI YAN YANLONG YANG YU TAN XUN CHEN YANG LI JUNLE QU TONG YE | 2017 | Photonics Research2017，5，3： | 5 |
| 14 | Influence of dynamic pressure on deep underground soft rock roadway support and its application显示文摘Due to high ground stress and mining disturbance, the deformation and failure of deep soft rock roadway is serious, and invalidation of the anchor net-anchor cable supporting structure occurs. The failure characteristics of roadways revealed with the help of the ground pressure monitoring. Theoretical analysis was adopted to analyze the influence of mining disturbance on stress distribution in surrounding rock,and the change of stress was also calculated. Considering the change of stress in surrounding rock of bottom extraction roadway, the displacement, plastic zone and distribution law of principal stress difference under different support schemes were studied by means of FLAC3D. The supporting scheme of U-shaped steel was proposed for bottom extraction roadway that underwent mining disturbance. We carried out a similarity model test to verify the effect of support in dynamic pressure. Monitoring results demonstrated the change rules of deformation and stress of surrounding rock in different supporting schemes. The supporting scheme of U-shaped steel had an effective control on deformation of surrounding rock. The scheme was successfully applied in underground engineering practice, and achieved good technical and economic benefits. | Meng Qingbin Han Lijun Chen Yanlong Fan Jiadong Wen Shengyong Yu Liyuan Li Hao | 2016 | International Journal of Mining Science and Technology2016，26，5： | 4 |
| 15 | Leukotriene D4 induces amyloid-β generation via CysLT1R-mediated NF-κB pathways in primary neurons显示文摘 | Xiaoyun Wang SusuTang Yanlong Yongqi Li Mingxing Liao Mei Hu Hui Ji Hao Hong | 2013 | 中国药理通讯2013，30，2： | 4 |
| 16 | Metamorphic, deformation, fluids and geological significance of low-temperature retrograde mylonites of Diancangshan metamorphic massif along Ailaoshan-Red River strike-slip fault zone, Yunnan, China显示文摘Diancangshan metamorphic massif is one of the four metamorphic massifs developed along the Ailaoshan-Red River strike-slip fault zone, Yunnan, China. It has experienced multi-stage metamorphism and deformation, especially since the late Oligocene it widely suffered high-temperature ductile shear deformation and exhumation of the metamorphic rocks from the deep crust to the shallow surface. Based on the previous research and geological field work, this paper presents a detailed study on deformation and metamorphism, and exhumation of deep metamorphic rocks within the Diancangshan metamorphic massif,especially focusing on the low-temperature overprinted retrogression metamorphism and deformation of mylonitic rocks. With the combinated experimental techniques of optical microscope, electron backscatter diffraction attachmented on field-emission scanning electron microscopy and cathodoluminescence, our contribution reports the microstructure, lattice preferred orientations of the deformed minerals, and the changes of mineral composition phases of the superposition low-temperature retrograde mylonites. All these results indicate that:(1) Diancangshan deep metamorphic rock has experienced early high-temperature leftlateral shear deformation and late extension with rapid exhumation, the low-temperature retrogression metamorphism and deformation overprinted the high-temperature metamorphism, and the high-temperature microstructure and texture are in part or entirely altered by subsequent low-temperature shearing;(2) the superposition of low-temperature deformation-metamorphism occurs at the ductile-brittle transition; and(3) the fluid is quite active during the syn-tectonic shearing overprinted lowtemperature deformation and metamorphism. The dynamic recrystallization and/or fractures to micro-fractures result in the strongly fine-grained of the main minerals, and present strain localization in micro-domians, such as micro-shear zones in the mylonites. It is often accompanied by the decrease of rock strength and finally influences the rheology of the whole rock during further deformation and exhumation of the Diancangshan massif. | Xuemei CHENG Shuyun CAO Junyu LI Zunpu YU Yanlong DONG Meixia LV Junlai LIU | 2018 | Science China Earth Sciences2018，61，8： | 4 |
| 17 | The analysis of electrical performances of nanowires silicon solar cells显示文摘A theoretical model of silicon solar cells with ultra-small textured surface has been established based on depletion approximation and drift diffusion theory. The ultra-small textured surface achieves the low reflectance by multiple reflections among the silicon nanowires(NWs) . The electrical performances of the solar cells,including open circuit voltage(Voc),short circuit current(Isc) and conversion efficiency(η),are analyzed by the theoretical model. The results show that the low reflectance is not the only pursuit in manufacturing the Si NWs solar cells. Other factors including optimizing the surface passivation,improving the silicon wafers quality and designing the proper nanowire length should be considered together with NWs structure. | LI HaoFeng JIA Rui DING WuChang CHEN Chen MENG YanLong LIU XinYu | 2011 | Science China(Technological Sciences)2011，54，12： | 4 |
| 18 | Decentralized Attribute-Based Encryption and Data Sharing Scheme in Cloud Storage显示文摘In this paper, we consider the problems of data sharing between multiple distrusted authorities. Prior solutions rely on trusted third parties such as CAs, or are susceptible to collusion between malicious authorities, which can comprise the security of honest ones. In this paper, we propose a new multi-authority data sharing scheme – Decentralized Multi-Authority ABE(DMA), which is derived from CP-ABE that is resilient to these types of misbehavior. Our system distinguishes between a data owner(DO) principal and attribute authorities(AAs): the DO owns the data but allows AAs to arbitrate access by providing attribute labels to users. The data is protected by policy encryption over these attributes. Unlike prior systems, attributes generated by AAs are not user-specific, and neither is the system susceptible to collusion between users who try to escalate their access by sharing keys. We prove our scheme correct under the Decisional Bilinear Diffie-Hellman(DBDH) assumption; we also include a complete end-to-end implementation that demonstrates the practical efficacy of our technique. | Xiehua Li Yanlong Wang Ming Xu Yaping Cui | 2018 | China Communications2018，15，2： | 4 |
| 19 | New Approaches and Markers for Identifying Secondary Biogenic Coalbed Gas显示文摘According to the adsorption-desorption characteristics of coalbed gas and analysis of various experimental data,this paper proposes that the generation of secondary biogenic gas(SBG) and its mixing of with the residual thermogenic gas at an early stage inevitably lead to secondary changes of the thermogenic gas and various geochemical additive effects.Experimental results also show that the fractionation of the carbon isotope of methane of coal core desorption gas changes very little;the δ13C1 value of the mixed gas of biogenic and thermogenic gases is between the δ13C1 values of the two 'original' gases,and the value is determined by the carbon isotopic compositions and mixing proportions of the two 'original' methanes.Therefore this paper proposes that the study on the secondary changes of the thermogenic gas and various additive effects is a new effective way to study and identify SBG.Herein,a systematic example of research on the coalbed gas(Huainan coalbed gas) is further conducted,revealing a series of secondary changes and additive effects,the main characteristics and markers of which are:(1) the contents of CO2 and heavy-hydrocarbons decrease significantly;(2) the content of CH4 increases and the gas becomes drier;(3) the δ13C and δD values of methane decrease significantly and tend to have biogenetic characteristics;and(4) the values of δ13C2 and δ13CCO2 grow higher.These isotopic values also change with the degradation degrees by microbes and mixing proportions of the two kinds of gases in different locations.There exists a negative correlation between the δ13C1 vs δ13CCO2 values.The △δ13CC2-C1 values obviously become higher.The distributions of the △δ13CCO2-C1 values are within certain limits and show regularity.There exist a positive correlation between the N2 versus Ar contents,and a negative correlation between the N2 versus CH4 contents,indicating the down forward infiltration of the surface water containing air.These are important markers of the generation and existence of SBG. | TAO Mingxin LI Jing LI Xiaobin MA Yuzhen LI Zhongping WANG Zuodong GAO Zhongliang ZHANG Xiaojun WANG Yanlong | 2012 | Acta Geologica Sinica(English Edition)2012，86，1： | 4 |
| 20 | Two Types of Granites in the Western Yangtze Block and Their Implications for Regional Tectonic Evolution: Constraints from Geochemistry and Isotopic Data显示文摘In the western Yangtze Block, widespread Mesoproterozoic to Neoproterozoic rocks are the key to understanding the Precambrian tectonic-magmatic evolution of the region. However, their petrogenesis and tectonic setting are still controversial. In this paper, zircon U-Pb ages, Sm-Nd isotopic and whole-rock geochemical data are reported from selected fresh samples in the southern Dechang county, southwestern China, in order to constrain their emplacement age and magma source, as well as their petrogenesis and tectonic setting. They are mainly composed of biotite monzogranite, monzonitic granite, biotite granodiorites, and quartz diorite. Two ages of 1055 ± 43 Ma and 837.6 ± 3.8 Ma were obtained through zircon U-Pb dating by LA-ICP-MS and LA-MC-ICP-MS, respectively. According to their major element compositions, the Grenville-age granites are peraluminous calc-alkaline series calcic S-type granite. In contrast, the mid-Neoproterozoic granites are metaluminous calc-alkaline series alkalic I-type granite. Furthermore, the S-type granites are enriched in LREEs relative to HREEs with(La/Yb)_N ratios of 3.85–18.56 and underwent major fractionation with strongly negative Eu anomalies(Eu/Eu~* = 0.38–0.66). In the MORB-normalized trace element variation diagram, all the samples are enriched in Ce and large ion lithophile elements such as Rb, Th, and K, and depleted in high field strength elements such as Nb, and Ti, with negative Sr and Ti anomalies. The I-type granites are enriched in LREEs with slight negative Eu anomalies(Eu/Eu~* = 0.83–0.93). They are characterized by the enrichment of highly incompatible elements(such as K, Rb, Ba, Th) and LREEs, relative to MORB. Neodymium isotopic data show that the S-type granites display ^(143)Nd/(^(144) Nd) values of 0.51241–0.51256, and have ε_(Nd)(t = 1055 Ma) values of(-3.29) to(-3.81). Calculated t_(DM) ages yield values from 1.87 to 1.91 Ga with the t_(DM).2 stg ages of 1.86 to 1.9 Ga. The I-type granites have ^(143)Nd/(^(144) Nd) ratios between 0.51192 and 0.51195, corresponding to initial ε_(Nd)(t = 837 Ma) values of 1.22 to 5.63. Calculated t_(DM) ages yield values from 1.0 to 1.38 Ga and the t_(DM).2 stg ages yield values from 0.99 to 1.06 Ga. The S-type granites are distinguished as syn-collision granite, whereas the I-type granites were formed as arc magmas according to the Rb-(Yb+Ta) and R_1-R_2 tectonic discrimination diagrams. To conclude, there are two types of spatially associated granite, the Mesoproterozoic S-type granite which were derived from remelting of upper crustal mudstone and/or clastics and resulted from the convergence of two continental plates, and the mid-Neoproterozoic I-type granite which formed in continental arc and resulted from mantle-derived magma mixed crust material, in the western Yangtze Block. Furthermore, we suggest that collision between the Yangtze and Cathaysia blocks occurred at about 1055 Ma, and caused the Stype granite. The I-type granite related to the subduction of oceanic lithosphere eastward underneath the Yangtze Block in the mid-Neoproterozoic. | MABI Awei YANG Zhengxi ZHANG Mingchun WEN Dengkui LI Yanlong LIU Xuyang | 2018 | Acta Geologica Sinica(English Edition)2018，92，1： | 4 |
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