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Geochemical characteristics of Carboniferous volcanic rocks from the Wulungu-Luliang area, Junggar basin: constraints on magma source and tectonic setting

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Chinese Journal Of Geochemistry 2015年第4期34卷 515-524页

作者： Wei Liu Kuihua Zhang Guanlong Zhang Peiming Zhou qizhi Wang School of Resources and Geosciences China University of Mining and Technology The West Research Center Company of Sinopec Shengli Oilfield

The Carboniferous volcanic rocks in the Wulungu-Luliang area are mainly andesites of medium- to high-K calc-alkalic series. Volcanic rock samples have relatively high alkali(Na2O + K2 O = 4.7 % to 6.8 %) and low Ti O2contents(0.7 % to 0.9 %), relatively high Mg O(2.5 % to 3.4 %) and Mg#(49.9 % to 67.1 %), high rare earth element(REE) contents, and relatively high K2 O contents(1.7 % to 3.1 %). Chondrite-normalized REE patterns show light REE enrichment((La/Yb)N= 4.15 to 5.19)with weak Eu anomalies(d Eu = 0.75 to 0.92). These samples are enriched in large-ion lithophile elements but relatively depleted in high field strength elements. The trace elements and REE patterns are similar to those of Setouchi and central Ryukyu high-Mg andesites, indicating a highMg andesite source. Relatively high Y contents(16.7 to24.4 ppm), and relatively low Sr/Y ratios(17.2 to 38.8) and Ti O2contents(0.7 % to 0.9 %) exclude the possibility of slab melting. Low Sr/Nd(16.6 to 42.8), Ba/Th(66.4 to266.8), and U/Th(0.2 to 0.3) indicate that the influence of slab-derived fluids is low. The ratios of Ce/Th(4.9–7.3), Ce/Pb(1.8–4.2), Ba/Rb(7.99–22.03), Ba/Th(66.4–266.8), and La/Sm(3.6–4.3) are similar to ratios found in subducting sediment melts. Relatively high ratios of K/Nb(1357–3258),Th/La(0.28–0.42), Zr/Nb(8.8–27.1), and especially Th/Nb(0.48–1.25) suggest that the magma was assimilated and contaminated by upper continental crust. These characteristics, along with the ratios of La/Yb, Sc/Ni, Th/Yb, Ta/Yb,Ce/P2O5, and Zr/Ti O2, demonstrate that the earlier Carboniferous volcanic rocks in the Wulungu-Luliang area were generated in a continental island-arc setting.

关键词：火山岩地球化学特征石炭系岩浆源准噶尔盆地构造背景古陆高钾钙碱性系列

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Nucleation and Blunting of Nanocracks in Brass

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Journal of Materials Science & Technology 1998年第3期14卷 273-276页

作者： Gu, Biao Chu, Wuyang Qiao, Lijie Chen, qizhi Hsiao, Chimei Univ Sci & Technol Beijing Dept Mat Phys Beijing 100083 Peoples R China

In situ tensile test of brass foil specimens in TEM showed that many dislocations were emitted from a loaded crack tip, and a dislocation free zone (DFZ) was formed under the condition of constant displacement. The DFZ is an elastic zone, where the stress may equal to the cohesive strength sigma //t//h when the applied stress is high enough. As a result, nano-cracks would initiate discontinuously in the DFZ or, sometimes, at a blunted-crack tip. As soon as the nano-crack nucleated, it quickly blunts into a void, which results in ductile fracture. (Edited author abstract) 10 Refs.

关键词： Brass

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Failure Mechanism and Stability Analysis of an Active Landslide in the Xiangjiaba Reservoir Area,Southwest China

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Journal of Earth Science 2018年第3期29卷 646-661页

作者： Javed Iqbal Fuchu Dai Min Hong Xinbin Tu qizhi Xie Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China Department of Earth Sciences Abbottabad University of Sciences and TechnologyAbbottabad 22500Pakistan Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430071China Hydrochina Zhongnan Engineering Corporation Changsha 410014China

Dam construction for hydropower development is a very important subject all around the world, especially in developing countries due to energy crises. Filling of reservoir lakes may trigger or reactivate landslides in reservoir area. Active landslides in populated districts in the Xiangjiaba Reservoir area have become a striking problem for residents, local government and construction engineers. The key objective of this study is to analyze the role of reservoir filling and fluctuation in the activation/reactivation of the landslide as well as the mechanism of landslide from microstructures of pre-sheared slip surface. A large active landslide with a total volume of 1.25 Mm^3 at the left margin of Jinsha River in Pingshan County of Sichuan Province, Southwest China, was selected as a case study. Field investigation, field monitoring and laboratory tests were carried out to find out the failure mechanism and the stability of the active landslide. The shear strength test and stability analysis confirm that the water level fluctuations have an adverse effect on slope stability. It is obvious from microstructure analysis that the clay minerals contribute to down-slope movement at micro-scale as well as presence of expansive minerals （e.g., montmorillonite） decreases the strength of soil due to water level rise.

关键词： active landslide slope stability stability analysis microstructure montmorillonite.

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Ensemble Classifier Design Based on Perturbation Binary Salp Swarm Algorithm for Classification

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 653-671页

作者： Xuhui Zhu Pingfan Xia qizhi He Zhiwei Ni Liping Ni School of Management Hefei University of TechnologyHefei230009China School of Statistics Zhejiang Gongshang UniversityHangzhou310018China Key Laboratory of Process Optimization and Intelligent Decision-Making Ministry of EducationHefei230009China Collaborative Innovation Center for Statistical Data Engineering Technology and Application ZhejiangGongshang UniversityHangzhou310018China

Multiple classifier system exhibits strong classification capacity compared with single classifiers,but they require significant computational *** ensemble system aims to attain equivalent or better classification accuracy with fewer ***,current methods fail to identify precise solutions for constructing an ensemble *** this study,we propose an ensemble classifier design technique based on the perturbation binary salp swarm algorithm(ECDPB).Considering that extreme learning machines(ELMs)have rapid learning rates and good generalization ability,they can serve as the basic classifier for creating multiple candidates while using fewer computational ***,we introduce a combined diversity measure by taking the complementarity and accuracy of ELMs into account;it is used to identify the ELMs that have good diversity and low *** addition,we propose an ECDPB with powerful optimizing ability;it is employed to find the optimal subset of *** selected ELMs can then be used to forman ensemble *** on 10 benchmark datasets have been conducted,and the results demonstrate that the proposed ECDPB delivers superior classification capacity when compared with alternative methods.

关键词： Ensemble classifier salp swarmalgorithm diversity measure multiple classifiers system extreme learning machine

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Mechanics analysis of thin-walled box continuous girder with variable cross-sections in considering effect of large deflection and shear lag

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Frontiers of Structural and Civil Engineering 2009年第4期3卷 352-356页

作者： Yuji CHEN qizhi LUO Department of Civil Engineering and Architecture Foshan Science and Technology UniversityFoshan 528000China

In order to study the mechanics behavior of a thin-walled box continuous girder with variable crosssections,using potential variation theories,considering the effect of shear lag of flange’s stress and the nonlinear geometry of vertical displacement,and evolving five generalized displacements with the spline function,the large deflection problem of the thin-walled box continuous girder with variable cross-section was transformed to a nonlinear algebraic equation,which was solved using the Newton-Raphon iterative *** results of the calculation show that different shear lag warp functions to the cantilever,top and bottom plate should be taken to analyze the mechanics behavior of the thin-walled box continuous girder *** thin-walled box continuous girder with variable cross-sections has more reasonable stress state and is more adaptable for the longitudinal change of internal forces than that with equal *** effect of large deflection on the stress and displacement of the thin-walled box continuous girder with variable cross-sections depends on the values of the load.

关键词： thin-walled box girder with variable crosssections potential variational theory shear lag large deflection problem

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Earth Pressure of the Trapdoor Problem Using Three-Dimensional Discrete Element Method

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1503-1520页

作者： qizhi Chen ChuliXu Baoping Zou Zhanyou Luo Changjie Xu Xu Long School of Civil Engineering and Architecture Zhejiang University of Science and TechnologyHangzhou310023China School of Civil and Environmental Engineering Ningbo UniversityNingbo315211China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang330013China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China

Load transformation from the yielding part of the soil to the adjacent part is known as the soil arching effect,which plays an important role in the design of various geotechnical ***’s trapdoor test was an importantmilestone in the development of theories on soil *** research on earth pressure of the trapdoor problem is presented in this paper using the three-dimensional(3D)discrete element method(DEM).Five 3D trapdoor models with different heights are established by 3DDEMsoftware PFC *** variation of earth pressure on the trapdoor with the downward movement of the trapdoor,the distribution of vertical earth pressure along the horizontal direction,the distribution of vertical earth pressure along the vertical direction,the distribution of lateral earth pressure coefficient along the depth direction,the magnitude and direction of contact force chain are studied,*** research results show that the earth pressure on the trapdoor decreases rapidly after the downward movement of the trapdoor,and then reaches the minimum earth *** that,the earth’s pressure will rise slightly,and whether this phenomenon occurs depends on the depth *** the bottom soil,due to the stress transfer caused by the soil arching effect,the ratio of earth pressure in the loose area decreases,while the ratio of earth pressure in the stable area *** the trapdoor moving down,the vertical earth pressure along the depth in the stable zone is basically consistent with the initial state,which shows an approximate linear *** the trapdoor moves down,the distribution of earth pressure along with the depth in the loose area changes,which is far less than the theoretical value of vertical earth pressure of its *** of the compression of the soil on both sides,the lateral earth pressure coefficient of most areas on the central axis of the loose zone is close to the passive earth pressure coefficient ***

关键词： Soil arching effect three dimensional discrete element earth pressure contact force chain

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Computed tomography (CT) of nasal cavity of Ikechosaurus sunailinae (Reptilia: Choristodera)

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Chinese Science Bulletin 1999年第24期44卷 2277-2281页

作者： Junchang Lü qizhi Zhu Xikan Cheng Xiangke Du Chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China Beijing Med Univ Renmin Hosp Dept Radiol Treatment Beijing 100044 Peoples R China

The CT technique was first applied to observing the nasal cavity of Ikechosaurus sunailinae. The results indicate that the nasal cavity is very complex, and it was divided into two parts: the posterior-upper part and ... 详细信息

关键词： CT scan thermoregulation nasal cavity Ikechosaurus.

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Multidimensional autophagy nano-regulator boosts Alzheimer's disease treatment by improving both extra/intraneuronal homeostasis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1380-1399页

作者： Yixian Li Peng Yang Ran meng Shuting Xu Lingling Zhou Kang Qian Pengzhen Wang Yunlong Cheng Dongyu Sheng Minjun Xu Tianying Wang Jing Wu Jinxu Cao qizhi Zhang Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai 201203China

Intraneuronal dysproteostasis and extraneuronal microenvironmental abnormalities in Alzheimer’s disease(AD)collectively culminate in neuronal *** the context of AD,autophagy dysfunction,a multi-link obstacle involving autophagy downregulation and lysosome defects in neurons/microglia is highly implicated in intra/extraneuronal pathological ***,multidimensional autophagy regulation strategies co-manipulating“autophagy induction”and“lysosome degradation”in dual targets(neuron and microglia)are more reliable for AD ***,we designed an RP-1 peptide-modified reactive oxygen species(ROS)-responsive micelles(RT-NM)loading rapamycin or gypenoside *** by RP-1 peptide,the ligand of receptor for advanced glycation end products(RAGE),RT-NM efficiently targeted neurons and microglia in AD-affected *** nanocombination therapy activated the whole autophagy-lysosome pathway by autophagy induction(rapamycin)and lysosome improvement(gypenoside XVII),thus enhancing autophagic degradation of neurotoxic aggregates and inflammasomes,and promoting Aβ ***,it decreased aberrant protein burden,alleviated neuroinflammation,and eventually ameliorated memory defects in 3×Tg-AD transgenic *** research developed a multidimensional autophagy nano-regulator to boost the efficacy of autophagy-centered AD therapy.

关键词： Autophagy-lysosome pathway Alzheimer’s disease Proteostasis Neuroinflammation Multi-target therapy Rapamycin Gypenoside XVII Cascade dual-targeting

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Modulating autophagic flux via ROS-responsive targeted micelles to restore neuronal proteostasis in Alzheimer’s disease

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Bioactive Materials 2022年第5期7卷 300-316页

作者： Shuting Xu Peng Yang Kang Qian Yixian Li Qian Guo Pengzhen Wang Ran meng Jing Wu Jinxu Cao Yunlong Cheng Minjun Xu qizhi Zhang Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai201203China

Compromised autophagy and defective lysosomal clearance significantly contribute to impaired neuronal proteostasis,which represents a hallmark of Alzheimer’s disease(AD)and other age-related neurodegenerative *** evidence has implicated that modulating autophagic flux,instead of inducing autophagosome formation alone,would be more reliable to rescue neuronal ***,selectively enhancing drug concentrations in the leision areas,instead of the whole brain,will maximize therapeutic efficacy while reduing non-selective autophagy ***,we design a ROS-responsive targeted micelle system(TT-NM/Rapa)to enhance the delivery efficiency of rapamycin to neurons in AD lesions guided by the fusion peptide TPL,and facilitate its intracellular release via ROS-mediated disassembly of micelles,thereby maximizing autophagic flux modulating efficacy of rapamycin in ***,it promotes the efficient clearance of intracellular neurotoxic proteins,β-amyloid and hyperphosphorylated tau proteins,and ameliorates memory defects and neuronal damage in 3×Tg-AD transgenic *** studies demonstrate a promising strategy to restore autophagic flux and improve neuronal proteostasis by rationally-engineered nano-systems for delaying the progression of AD.

关键词： Autophagic flux ROS-Responsive micelle system Brain-neuron targeting Rapamycin Alzheimer’s disease

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Numerical simulation of temporal and spatial evolution of fold-thrust belts in the northern and northeastern margins of the Qinghai-Tibetan Plateau

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Earthquake Research Advances 2021年第S01期1卷 23-25页

作者： qizhi Chen Caibo Hu School of Earth and Planetary Sciences University of Chinese Academy of SciencesKey Laboratory of Computational GeodynamicsChinese Academy of SciencesBeijingChina

Fold-thrust belts are common structural styles under the background of long-term regional tectonic *** northern and northeastern margins of the Qinghai-Tibetan Plateau are located on the edge of the growth and expansion of the Qinghai-Tibetan *** nearly 10 Ma,some significant and typical fold thrust belt have been *** spatial-temporal evolution of these fold-thrust belts and the characteristics of surface deformations are significant issues in *** this paper,we use the elastoplastic finite element model with considering the contact nonlinearity to study the spatialtemporal evolution of the fold-thrust belts in the northern and northeastern margins of the Qinghai-Tibetan Plateau,with particular attention to the details of the relationship between the depth and the shallow,the spatialtemporal order,and the characteristics of the surface deformation,etc.,in order to make a relatively complete mechanical interpretation of the spatial-temporal evolution of the foldthrust belts in the northern and northeastern margins of the Qinghai-Tibetan Plateau from the perspective of geodynamics.

关键词： Fold-thrust belts Finite element model Elastoplasticity Northeastern margin of the Qinghai-Tibetan Plateau Frictonal contact

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