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U-Pb dating of detrital zircons from the Wudangshan Group in the South Qinling and its geological significance

Chinese Science Bulletin 2010年第22期55卷 2440-2448页

作者： LING WenLi DUAN RuiChun liu xiaoming CHENG JianPing MAO XinWu PENG LianHong liu ZaoXue YANG HongMei REN BangFang Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China Yichang Institute of Geology and Mineral Resources Yichang 443003 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China Tianjin Institute of Geology and Mineral Resources Tianjin 300170 China

U-Pb dating was made by the LA-ICP-MS method for detrital zircons from the Wudangshan volcanic-sedimentary succession in the South Qinling. Samples comprise quartz sandstones of the Wudangshan Group collected from the base of the Yangping For-mation and an upper layer of the Shuangtai Formation overlain its volcanic sequence, and two river-sand collections from the drainage systems cutting across the two formations, respectively. The results show that the Yangping detrital zircons are domi-nated by 830–780 Ma grains with a minor population of ～1.0–0.84 Ga and sporadic grains of ～2.6, ～2.4 and 2.0 Ga, whereas the Shuangtai zircons yield an upper intercept age of 763±33 Ma, identical to the timing of the Wudangshan volcanism within error, with few concordant grains of 1.9 and 0.86 Ga. Age spectra for the two river-sand samples are similar to those of the Yangping and Shuangtai Formations, respectively. It thus suggests that the Wudangshan strata are less than 780 Ma, whereas their major detrital zircon populations of 1.0–0.85 Ga and 830–780 Ma are consistent with timing of the Hannan magmatic activities along the northwestern margin of the South China Block. This suggests a Hannan or adjacent area provenance for the Wudangshan strata. The Wudang area is characterized by rift-related igneous events at ～755 and ～680 Ma, respectively, pointing to a tectono-magmatic history different from the Hannan area. It is inferred that the ～755 Ma magmatism is likely to indicate a separation of the South China Block from the supercontinent Rodinia, while the ～680 Ma event suggests a further split between the South Qinling and some unknown continent.

关键词：碎屑锆石武当山南秦岭地质意义 Pb 岩浆活动石英砂岩火山沉积

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Timing of the Wudangshan, Yaolinghe volcanic sequences and mafic sills in South Qinling: U-Pb zircon geochronology and tectonic implication

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Chinese Science Bulletin 2008年第14期53卷 2192-2199页

作者： LING WenLi REN BangFang DUAN RuiChun liu xiaoming MAO XinWu PENG LianHong liu ZaoXue CHENG JianPing YANG HongMei Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Process and Mineral Resources China University of Geosciences Wuhan 430074 China State Key Laboratory of Continental Geodynamics Northwest University Xi'an 710069 China Geological Survey of Hubei Province Wuhan 430022 China

The Wudangshan, Yaolinghe volcanic-sedimentary sequences and doleritic-gabbroic sills comprise the largest exposed Precambrian basement in South Qinling. Zircons separated from 5 volcanic-pyroclas- tic samples of the Wudangshan Group, 2 volcanic samples of the Yaolinghe Group and one sample for the mafic sills were used for U-Pb dating by laser ablation-inductively coupled plasma mass spec- trometry (LA-ICPMS). The results reveal that the Wudangshan volcanic sequence was formed at (755±3) Ma (a weighted mean from the 5 samples, MSWD=0.47), whereas the Yaolinghe volcanic suite and the mafic sill were crystallized at (685±5) (2 samples, MSWD=0.36) and (679±3) Ma (MSWD=1.6), respectively, which are equal to each other within analysis errors. These ages are markedly younger than those previously documented for the rocks. The newly obtained ages for the Wudangshan and Yaolinghe Groups are identical to those of the bottom Liantuo and slightly older than those of the Nantuo Forma- tions, respectively, lower strata of the Nanhua (middle to late Neoproterozoic) stratotype section in eastern Three Gorges, Yangtze craton. A range of inherited magmatic zircons was recognized with ages of 830 to 780 Ma, which are typical of Neoprotzrozoic magmatisms recorded along the margins and interior of the Yangtze craton. Thus, there is Neoproterozoic basement comprising 830―780 Ma igne- ous suites in South Qinling; the inherited zircons were detrital sediments derived from the northern margin of the Yangtze craton. Accordingly, it is suggested that the South Qinling is a segment of the Yangtze craton before the Qinling Orogeny.

关键词：武当山铁镁质岩床地质年代地质学

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Chemotherapy-induced small extracellular vesicles prime the pre-metastatic niche to accelerate neuroblastoma metastasis

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Genes & Diseases 2024年第4期11卷 65-68页

作者： Carson A.Wills xiaoming liu Longgui Chen Yuanjun Zhao Zhenqiu liu Vladimir S.Spiegelman Jeffrey Sundstrom Hong-Gang Wang Department of Pediatrics Division of Pediatric Hematology and OncologyThe Pennsylvania State University Collegeof MedicinePA 17033USA Department of Ophthalmology The Pennsylvania State University College of MedicinePA 17033USA Department of Public Health Sciences The Pennsylvania StateUniversityCollegeofMedicinePA 17033USA

Neuroblastoma is the most common extracranial solid tumor in children,accounting for more than 10%of cancerrelated deaths in this *** standard of care for patients diagnosed with medium-to high-risk neuroblastoma,incl... 详细信息

关键词： neuroblastoma metastatic metastasis

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NOVEL METHOD SOLVING NUMERICAL INSTABILITIES IN TOPOLOGY OPTIMIZATION

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 22-26页

作者： Guo Dongming Wang xiaoming liu Zhenyu Department of Mechanical Engineering，Dalian University of Technology， Dalian 116023，China Department of Mehanical Engineering Dalian University of Technology Dalian 116023

Numerical instabilities are often encountered in FE solution of continuumtopology optimization. The essence of the numerical instabilities is given from the inverse partialdifferential equation (PDE) point of view. On the basis of the strict mathematical theory, a novelmethod, named as window filter and multi-grid method, which solves the numerical instabilities, isproposed. Convergent analyses and a numerical example are presented.

关键词： Topology optimization Gaussian windows Checkerboard pattern

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The protective effect of lactose on the bile salt stress response of Streptococcus thermophilus is strain dependent

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Food Bioscience 2023年第3期53卷 802-808页

作者： Yuqi Pan Peng Yu Yang Jiang xiaoming liu Jianxin Zhao Hao Zhang Wei Chen State Key Laboratory of Food Science and Technology Jiangnan UniversityWuxiJiangsu214122China School of Food Science and Technology Jiangnan UniversityWuxiJiangsu214122China International Joint Research Laboratory for Pharmabiotics&Antibiotic Resistance Jiangnan UniversityWuxiJiangsu214122China Wuxi Translational Medicine Research Center and Jiangsu Translational Medicine Research Institute Wuxi Branch China National Engineering Research Centre for Functional Food WuxiJiangsu214122China

Streptococcus thermophilus is generally considered to be sensitive to bile salt stimulation,and its bile salt tolerance is strain *** this study,the viable bacteria count,sugar utilization capacity,β-galactosidase activity,and extracellular polysaccharide synthesis capacity of 5 strains of Streptococcus thermophilus in bile salt with or without(w/o)lactose were measured to explore the protective ability of lactose to the *** changes in gene expression in stress and carbohydrate metabolism-related pathways were *** results indicated that the protective effect of lactose on the bile salt stress response of Streptococcus thermophilus is strain ***β-galactosidase activity of the strains was correlated with the yield of exopolysaccharides(EPS)significantly,and the strain with a high survival rate(4M6)showed higher lactose utilization,β-galactosidase activity and more EPS production in general.

关键词： Streptococcus thermophilus Bile salt Lactose utilization Exopolysaccharides

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Optimizing the grain size and grain boundary morphology of (K,Na) NbO_(3)-based ceramics: Paving the way for ultrahigh energy storage capacitors

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Journal of Materiomics 2021年第4期7卷 780-789页

作者： Xiaozhi Wang Yu Huan Peiyao Zhao xiaoming liu Tao Wei Qiwen Zhang Xiaohui Wang School of Material Science and Engineering University of JinanJinan250022China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China The Chinese Ceramic Society Beijing100831China

Relaxor dielectric ceramic capacitors are very attractive for high-power energy ***,the low breakdown strength severely restricts improvements to the energy storage density and practical ***,a strategy of designing small grain sizes and abundant amorphous grain boundaries is proposed to improve the energy storage properties under the guidance of phase field theory.0.925(K_(0.5)Na_(0.5))NbO_(3)-e0.075Bi(Zn_(2/3)(Ta_(0.5)Nb_(0.5))1/3)O_(3)(KNNe-BZTN)relaxor ferroelectric ceramic is taken as an example to verify our *** grain sizes and grain boundaries of the KNNeBZTN ceramics are carefully controlled by the high-energy ball milling method and twoestep sintering *** analysis and diffusion reflectance spectra demonstrate that KNNeBZTN ceramics with a small grain size and abundant amorphous grain boundary exhibit a lower charge carrier concentration and higher band *** a consequence,the breakdown electric field of KNNeBZTN ceramics increases from 222 kV/cm to 317 kV/cm when the grain size is decreased from 410 nm to 200 nm,accompanied by a slightly degraded maximum *** ceramics with an average grain size of~250 nm and abundant amorphous grain boundaries exhibit optimum energy storage properties with a high recoverable energy density of 4.02 J/cm^(3) and a high energy efficiency of 87.4%.This successful local structural design opens up a new paradigm to improve the energy storage performance of other dielectric ceramic capacitors for electrical energy storage.

关键词： Grain size Grain boundary KNN-based dielectric ceramic capacitors Energy storage properties Breakdown strength Two-step sintering strategy

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Identification of tumorigenic risk genes in human placenta-derived mesenchymal stem cells treated with 3-methylcholanthrene

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BIOCELL 2022年第2期46卷 479-493页

作者： YUANYUAN JIA XIAONA MA XIURUI YAN JING XUE TINGTING YANG XUEYUN LIANG xiaoming liu Institute of Human Stem Cell Research General Hospital of Ningxia Medical UniversityYinchuan750004China

Mesenchymal stem cells(MSCs)capable of tumour topotaxis have been served as cellular vehicles to deliver anti-tumour *** cellular components of the tumour microenvironment,MSCs also affect tumour ***,the tumour transformation-related genes of MSCs remain unclear since either tumorigenic or tumour suppressor effects within these cells have been ***,we aimed to identify potential biomarkers indicative of tumorigenic risk by RNA-seq analysis of human placenta tissue-derived MSCs(hPTMSCs)exposed to the carcinogenic agent,3-methylcholanthrene(3-MC).Twenty-nine tumour transformation-related genes and three pluripotency-related genes were appraised as differentially expressed genes(DEGs)in *** of sfrp1 led to reduced cell viability,migration,and colony formation in *** contrast,the overexpression of ptgs2 exerted the opposite *** results indicate that A549 cells with high ptgs2 expression but low sfrp1 expression may have a more potential tumorigenic *** together,this study suggests that ptgs2 and sfrp1 may be tumorigenic risk genes.

关键词： Human placenta-derived mesenchymal stem cells Transcriptional profile Tumorigenicity

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Villagers'Satisfaction Evaluation of Rural"Toilet Revolution"in Qinghai Province:A Case Study of Huzhu Tu Autonomous County

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Asian Agricultural Research 2021年第11期13卷 1-6,10页

作者： xiaoming liu Qinghai University School of Finance and Economics Xining 810016China

With the effect of rural toilet improvement and villagers’satisfaction as the evaluation targets,the evaluation index system was constructed by mastering the actual situation of rural toilet improvement in Huzhu County,including villagers’acceptability of rural toilets,construction of toilets after improvement,treatment methods and effects of fecal sewage,management of toilet equipment after toilet *** indexes were assigned with weights by expert scoring,and the evaluation model of the effect of rural toilet improvement in Huzhu County was established by entropy weight method and fuzzy evaluation analysis *** result is of great significance to the follow-up management and protection of rural toilets.

关键词： Toilet improvement Rural revitalization Toilet revolution Huzhu County

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Solubility of β-cyclodextrin in different mixed solvents

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Petroleum Science 2008年第3期5卷 263-268页

作者： Yu Yong Li Jiguang Sun Yan Liang Qianqing Peng xiaoming liu Yansheng Hu Yufeng Laboratory of Green Chemistry and Chemical Engineering China University of Petroleum Beijing 102249 China

The solubility of β-cyclodextrin （β-CD） in ionic liquid/N, N-dimethyl-acetamide （IL/DMAC） mixed solvent and in LiCI/DMAC mixed solvent was investigated at 323.15 K and 353.15 K. The results showed that the solubility of β-CD in IL/DMAC system increased with increasing temperature, but decreased in LiCI/DMAC system. β-CD had the highest solubility in IL/DMAC system with [Cl]- or [Br]- anions. The solubility of β-CD in LiCl/DMAC system was lower than that in IL/DMAC system with [Cl]- or [Br]- anions but higher than that in IL/DMAC system with weak-coordinated anions （e.g [BF4]- or [PF6]-）. The effects of substituent groups （benzyl and butyl） of cation and the structure of cations on β-cyclodextrin solubility were also investigated.

关键词： β-cyclodextrin ionic liquid solubility mixed solvent

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Reasoning calculation of the electrical vehicle recharging service network construction via fitting prediction

Reasoning calculation of the electrical vehicle recharging s...

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第25届中国控制与决策会议

作者： Niu Xinsheng Li Xiaolei Li Huan Zhang Chengjin liu xiaoming Power Economic Institute of Technology Shandong Electric Power Corporation School of Control Science and Engineering Shandong University

ISBN: (纸本)9781467355339

The developing trend of the electrical vehicle recharging service network is analyzed in a reasoning calculation method for the coming several years. To simulate the developing conditions of related factors, some fitting prediction models are proposed based on the statistical data of the last several years. They are China’s automobile increasing model, China’s electrical vehicle increasing model, electricity price prediction model, and so on. Also, the configuration, investment, and revenue model of the electrical vehicle recharging service networks are proposed. We select Jinan as a typical city to make a calculation for service networks’ development. And we draw the conclusion that the service network will get refunding till 2017 to 2020.

关键词： Electrical Vehicle Recharging Service Network Fitting Prediction Model Reasoning Calculation

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