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Geochemistry of the Middle to Late Permian limestones from the marginal zone of an isolated platform(Laibin,South China)

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Science China Earth Sciences 2013年第10期56卷 1688-1700页

作者： qiu Zhen WANG QingChen yan DeTian State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of Sciences PetroChina Research Institute of Petroleum Exploration and Development Key Laboratory of Tectonics and Petroleum Resources of Ministry of Education University of Geosciences

Major, trace and rare earth elements were measured in 27 samples of the Middle to Late Permian limestones from the Tieqiao section located on the marginal zone of an isolated platform （Laibin, South China）. Shale-normalized REE＋Y patterns of all samples show notably negative Ce anomalies （0.21-0.66, average 0.33）, slightly positive Gd anomalies （1.08-1.30, average 1.20）, and positive Y anomalies with superchondritic Y/Ho ratios （36-91, average 55）, which are consistent with those of modern shallow seawater. Their relative LREEs enrichment with higher NdsN/YbsN ratios （0.58-1.80） than those of modern shallow seawater （0.21-0.50） suggests complicated sources of REEs for all samples. Compared with geochemical features of sediments influenced by terrigenous particles and hydrothermal fluids, it is concluded that ambient shallow seawater was the primary source of REEs in these limestones. Comparing the indicators of REE＋Y elements （ZREE, NdsN/YbsN, Ce/Ce＊, Gd/Gd＊, Eu/Eu＊ and Y/Ho） in limestones with those in bedded cherts from the Tieqiao section, we consider that limestone and bedded chert have similar sources of REE＋Y elements： ambient shallow seawater with more or less hydrothermal fluids. In addition, there is a completely negative correlation between CaCO3 and SiO2 contents in limestones and bedded cherts. These results imply that precipitation of CaCO3 was inhibited by that of SiO2 which was derived mainly from hydrothermal fluid, es- pecially in bedded cherts from the Tieqiao section.

关键词： geochemistry rare earth element limestone the Middle to Late Permian South China

Early Cretaceous Post-Collisional Collapse of the Yidun Terrane: Geochronological and Geochemical Constraints from Calc-alkaline to Alkaline Basalts in Xiqiu Area, Southwest China

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Journal of Earth Science 2018年第1期29卷 57-77页

作者： Xutuo Li Danping yan Liang qiu State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences

Several Cretaceous Carlin-like or hydrothermal gold deposits along the Garze-Litang suture zone and Early Cretaceous hydrothermal copper mineralization along the southeastern margin of the Songpan-Garze fold belt were presumed to have a magmatic heat source. However, no actual coeval mag- matic events nearby were discovered. Here, we report zircon SIMS U-Pb age, whole-rock geochemical and Sr-Nd isotopic data of the Xiqiu basalts in the southern end of the Yidun terrane, eastern Tibetan Plateau. New zircon U-Pb ages yield weighted mean ^206pb/^238U age of 117.7±1.6 Ma. The basalts are classified as calc-alkaline to alkaline and have relatively high MgO （4.77 wt.%-10.84 wt.%） and Mg number values （Mg^#=（100×Mg/（Mg＋Fe^2＋））; 45.35-67.28） and positive εNd（t）（t=118 Ma） values （＋1.86 to ＋3.2）, suggesting a OIB-like mantle source that is consistent with the normalized patterns of trace elements and rare earth elements （REEs）. Geochemical data suggest that the primary basaltic magma was generated by low degree partial melting of a heterogeneous source of peridotite-dominated with a minor component of garnet- eclogite or pyroxenite and experienced olivine＋clinopyroxene dominated fractional crystallization. The primary melt compositions calculated from the high MgO samples, in turn, suggest that the Xiqiu basalts were generated at 1.6-2.9 GPa with abnormally hot mantle potential temperatures from 1 465 to 1 540℃. The melting temperatures are similar to the abnormally hot mantle underneath the Colorado Plateau and hotter than the mid-ocean range basalt （MORB） mantle and normal intra-continental mantle. Combined with previous studies, the Cretaceous Xiqiu basalts allow us to reconstruct a tectonic and geodynamic evolution- ary model responsible for the Late Jurassic to Late Cretaceous geological records （magmatism, ore deposits and enhanced exhumation） in the Yidun terrane and southern Songpan-Garze fold belt.

关键词： Early Cretaceous mantle thermal state basalt Yidun terrane tectonic and geodynamic model.

Complete and Complete Moment Convergence for Weighted Sums of Widely Orthant Dependent Random Variables

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Acta Mathematica Sinica,English Series 2014年第9期30卷 1539-1548页

作者： De Hua qiu Ping yan CHEN School of Mathematics and Statistics Guangdong University of Finance & Economics Department of Mathematics Jinan University

In this paper, we establish a complete convergence result and a complete moment convergence result for weighted sums of widely orthant dependent random variables under mild conditions. As corollaries, the corresponding results for weighted sums of extended negatively orthant dependent random variables are also obtained, which generalize and improve the related known works in the literature.

关键词： Widely orthant dependent random variables extended negatively orthant dependent random variables complete convergence complete moment convergence

pH-Responsive supramolecular micelle based on host-guest interaction of poly(β-amino ester) derivatives and adamantyl-terminated poly(ethylene glycol) for cancer inhibition

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Chinese Chemical Letters 2018年第12期29卷 1839-1844页

作者： Zhuting yang yan Peng Liyan qiu Ministry of Educational (MOE) Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang University

Supramolecular structures have received growing attention and been widely applied in many ***, we synthesized hydrophobic β-cyclodextrin-contained poly(β-amino ester)(PAE-β-CD) and hydrophilic adamantyl-terminated poly(ethylene glycol)(PEG-AD) to form a supramolecular micelle via the host-guest interaction. The micelle displayed pH responsive structure change due to the transform of hydrophobic PAE core to hydrophilic form in weakly acid condition. After the anticancer drug curcumin(Cur) was loaded into the micelle, the drug release behavior of the Cur-loaded micelle was studied, and it turned out that the Cur-loaded supramolecular micelle could effectively unload the drug at pH ***, the antitumor efficiency of the Cur-loaded micelle was also examined both in vitro and in vivo, indicating considerable inhibition ratio as high as 62.14% against mouse sarcoma 180.

关键词： Supramolecules Micelle Poly(β-amino ester) pH-Sensitive β-Cyclodextrin Curcumin

Generalized Gr?tzsch ring function and generalized elliptic integrals

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Applied Mathematics(A Journal of Chinese Universities) 2016年第4期31卷 458-468页

作者： MA Xiao-yan qiu Song-liang TU Guo-yan Department of Mathematics Zhejiang Sci-Tech University Hangzhou 310018 China Tongji Zhejiang College Jiaxing 413000 China

Abstract. In this paper, we study the quotient of hypergeometric functions μα （r） in the theory of Ramanujan＇s generalized modular equation for α ∈（0, 1/2]. Several new inequalities are given for this and rela... 详细信息

关键词： Gaussian hypergeometric function generalized GrStzsch ring function generalized elliptic func-tion.

Emerging Molecular Targets for the Management of Cancer Pain

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Neuroscience Bulletin 2020年第10期36卷 1225-1228页

作者： Hai-yan Sheng Yu-qiu Zhang Department of Pathophysiology School of Basic Medical SciencesXinxiang Medical UniversityXinxiang 453003China State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science Department of Translational NeuroscienceJing*an District Centre Hospital of ShanghaiInstitutes of Brain ScienceInstitute of Integrative MedicineFudan UniversityShanghai 200032China

Pain is a common symptom in cancer patients,even long after the treatment has been *** 39.3%-66.4%of patients with cancer experience moderate to severe pain,especially those with advanced *** experience of pain severely affects the quality of life,including eating,sleeping,thinking,working,and even continuing *** the improvement of cancer treatment and the prolongation of survival time,safe and effective pain management has become a major problem encountered by many clinicians.

关键词： Pain cancer pain

Al 1060/Pure Iron Clad Materials by Vacuum Roll Bonding and Their Solderability

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Journal of Materials Science & Technology 2013年第10期29卷 948-954页

作者： Qian Wang Xuesong leng Jiuchun yan Weibing Guo Yu Fu Tianming Luan State Key Laboratory of Advanced Welding and Joining School of Materials Science and EngineeringHarbin Institute of Technology

Al 1060/pure iron clad materials were produced by vacuum roll bonding. The effects of preheating temperature, vacuum roll reduction and initial thickness of the A11060 sheet on the metal interface and bonding strength were investigated. The interfacial microstructure was investigated and the mechanical properties of the joint were evaluated by shear testing. The bonding strength of the clad materials was generally enhanced by increasing the total reduction or preheating temperature, which caused the metal interface to flatten. No obvious reaction or diffusion layer was observed at the interface between Al 1060 and pure iron. The bonding strength increased with decreasing the initial thickness of the Al 1060 sheets. The Al 1060/pure iron clad materials were soldered with Zn-Al alloy by using an ultrasonic-assisted method. Strong bonding of the Al 1060 layer and Al 7N01 was realized without obvious Al 1060 dissolution or effect on the initial interface of Al 1060/pure iron clad materials by soldering at relatively low temperature.

关键词： Al 1060/pure iron clad materials Vacuum roll bonding Bonding strength Ultrasonic-assisted soldering

Multiphysics simulation method of Lamb wavepropagation with piezoelectric transducers under load condition

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Chinese Journal of Aeronautics 2019年第5期32卷 1071-1086页

作者： Lei qiu Xixi yan Xiaodong LIN Shenfang YUAN Research Center of Structural Health Monitoring and Prognosis State Key Lab of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

Lamb Wave(LW) simulation under time-varying conditions is an effective and low cost way to study the problem of the low reliability of the structural health monitoring methods based on the LW and Piezoelectric Transducer(PT). In this paper, a multiphysics simulation method of the LW propagation with the PTs under load condition is proposed. With this method, two key mechanisms of the load influence on the LW propagation are considered and coupled with each other. The first mechanism is the acoustoelastic effect which is the main reason of the LW velocity change. The second key mechanism is the load influence on piezoelectric materials, which results in a change of the amplitude. Based on the computational platform of the COMSOL Multiphysics, a multiphysics simulation model of the LW propagation with the PTs under load condition is established. The simulation model includes two physical phenomena. The first one is called solid mechanics, which is used to simulate the acoustoelastic effect being combined with the hyperelastic material properties of the structure in which the LW propagates. The second one is called electromechanical coupling, which considers the simulation of the piezoelectric effect of the PTs for the LW excitation and sensing. To simulate the load influence on piezoelectric materials, a non-linear numerical model of the relationship between the load and the piezoelectric coefficient d31 is established based on an experiment of the load influence on the LW. The simulation results under uniaxial tensile load condition are obtained and are compared with the data obtained from the experiment. It shows that the variations of the phase velocity and amplitude of the LW obtained from the simulation model match the experimental results well.

关键词： Acoustoelastic effect Lamb wave Multiphysics simulation Piezoelectric coefficient Structural health monitoring Time-varying condition

A new nonfullerene acceptor with an extended π conjugation core enables ternary organic solar cells approaching 19%efficiency

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Nano Research 2024年第5期17卷 4062-4068页

作者： Chunyan Liu Nailiang qiu Zhengjin Li yan Lu School of Materials Science and Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials and Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China School of Chemistry Chemical Engineering and MaterialsJining UniversityQufu 273155China

In organic solar cells(OSCs),it is an effective way to improve the power conversion efficiency(PCE)by adding a guest component with appropriate absorption and energy levels in the host ***,a new nonfullerene acceptor(NFA)named TBF-2Cl was developed by the strategy of expanding theπconjugated core of 2,2’-(((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b’]dithiophene-2,7-diyl)bis(methaneylylidene))bis(5,6-dichloro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile(IDT-4Cl)with two benzene *** increase of benzene units,TBF-2Cl exhibits higher lowest unoccupied molecular orbital(LUMO)level of-3.75 eV than that of one benzene unit based NFA IDT-4Cl and fluorene core based NFA F-2Cl,which facilitates enhancing the open-circuit voltage(V_(oc))of ternary ***,TBF-2Cl film shows a medium optical bandgap with the absorption range from 500-800 nm,being well complementary with the wide bandgap polymer donor D18 and narrow bandgap NFA ***,a remarkable PCE of 18.92%with a high short-circuit current density(J_(sc))of 27.40 mA·cm^(-2),a fill factor(FF)of 0.749,especially an outstanding V_(oc) of 0.922 V was achieved for the optimal ternary device based on D18:TBF-2Cl:CH-6F,surpassing the binary counterpart(17.08%).The findings provide insight into the development of new guest acceptors for obtaining more efficient OSCs.

关键词： medium optical bandgap high lowest unoccupied molecular orbital(LUMO)level the third component ternary organic solar cell high open-circuit voltage