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The study of subduction channels:Progress,controversies,and challenges

Science China Earth Sciences 2020年第12期63卷 1831-1851页

作者： jianxin zhang Key Laboratory of Deep-Earth Dynamics of the Ministry of Land and Resources Institute of GeologyChinese Academy of Geological SciencesBeijing100037China

The subduction channel is defined as a relatively thin and weak zone with coherent kinematics between the descending and overriding plates during *** materials in the channel,showing the characteristics of mélange,consist of low-density,low-viscosity,highly sheared metasediments and/or serpentinite-rich matrix with relatively rigid *** channel materials flow downwards and upwards,forming a kind of channel *** on geophysical and geological observations on active oceanic subduction zones,combined with numerical simulations,the subduction channel model was initially set to shallow depths<30 *** the development of numerical simulation technology and fossil subduction zone investigations,the subduction channel model was extended to depths of 80-100 km to describe deeper geodynamic environments of oceanic subduction zones and explore the exhumation of high to ultrahigh pressure metamorphic *** is also extended to continental subduction zones in order to explain the exhumation of metamorphic rocks in different grades as well as fluid activity and crust-mantle interaction during continental *** there are a series of differences in material composition and slab/mantle interface property between the upper and lower plates,continental subduction channels exhibit many similarities in structure and dynamics to oceanic subduction *** studies have provided a fundamental understanding of the structural and dynamic characteristics of subduction channels,but many problems still need to be solved and *** particular,the fundamental characteristics of subduction channels obtained by numerical simulation need to be confirmed and modified through geological investigations of fossil subduction channels.

关键词： Plate interface Subduction channel Mélange Numerical modeling High-ultrahigh pressure metamorphism Exhumation mechanism

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Alloying effects of refractory elements in the dislocation of Ni-based single crystal superalloys

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Progress in Natural Science:Materials International 2016年第6期26卷 636-642页

作者： Shiyu Ma jianxin zhang Key Laboratory for Liquid–Solid Structural Evolution & Processing of Materials Ministry of Education School of Materials Science and EngineeringShandong University

The alloying effects of W, Cr and Re in the [100](010) edge dislocation cores(EDC) of Ni-based single crystal superalloys are investigated using first-principles based on the density functional theory(DFT). The binding energy, Mulliken orbital population, density of states, charge density and radial distribution functions are discussed, respectively. It is clearly demonstrated that the addition of refractory elements improves the stability of the EDC systems. In addition, they can form tougher bonds with their nearest neighbour(NN) Ni atoms,which enhance the mechanical properties of the Ni-based single crystal superalloys. Through comparative analysis, Cr-doped system has lower binding energy, and Cr atom has evident effect to improve the systemic stability. However, Re atom has the stronger alloying effect in Ni-based single crystal superalloys, much more effectively hindering dislocation motion than W and Cr atoms.

关键词： Ni-based single crystal superalloys Refractory elements Alloying effects First-principles

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大学生负性情绪的隐喻接纳2周在线干预研究

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中国心理卫生杂志 2025年第1期39卷 75-80页

作者：李若楠于婉蓉张建新张文彩中国科学院心理健康重点实验室中国科学院心理研究所北京100101 中国科学院大学心理学系北京100049

目的:探讨隐喻接纳干预改善大学生负性情绪的效果。方法:112名大学生被分配至隐喻组(n=40)、非隐喻组(n=36)和空白对照组(n=36)。2个干预组接受2周在线团体干预,空白对照组不接受干预。在基线、2周干预后、1周随访和3周随访时施测广泛... 详细信息

目的:探讨隐喻接纳干预改善大学生负性情绪的效果。方法:112名大学生被分配至隐喻组(n=40)、非隐喻组(n=36)和空白对照组(n=36)。2个干预组接受2周在线团体干预,空白对照组不接受干预。在基线、2周干预后、1周随访和3周随访时施测广泛性焦虑量表-7 (GAD-7)、患者健康问卷-9 (PHQ-9)、接纳与行动问卷第二版(AAQ-Ⅱ)和自评接纳条目。结果:2周干预后,隐喻组的GAD-7、PHQ-9和AAQ-Ⅱ得分均低于基线,自评接纳得分均高于基线(均P<0.01);非隐喻组1周随访时的GAD-7得分,2周干预后和1周随访时的PHQ-9得分及2周干预后、1周随访和3周随访时的AAQ-Ⅱ得分均低于基线(均P <0.05),而2周干预后、1周随访和3周随访时的自评接纳得分均高于基线(均P<0.001)。AAQ-Ⅱ得分的减少仅对隐喻接纳干预造成的GAD-7和PHQ-9得分的减少存在中介作用(95%CI=-2.39~-0.38、-2.65~-0.44)。结论:隐喻接纳在线干预持续改善焦虑情绪的效果更优,经验性回避的减少是隐喻接纳干预改善焦虑和抑郁情绪的重要因素。

关键词：治疗性隐喻接纳干预经验性回避负性情绪大学生

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Lawsonite-bearing eclogites in the north Qilian and north Altyn Tagh:Evidence for cold subduction of oceanic crust

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Chinese Science Bulletin 2006年第10期51卷 1238-1244页

作者： zhang jianxin MENG Fancong Institute of Geology Chinese Academy of Geological Sciences Beijing100037 China

Lawsonite-bearing eclogites are recog-nized respectively in the north Qilian (NQL) and north Altyn Tagh (NAT), based on petrography and mineral chemistry. Lawsonite coexists with omphacite and phengite as inclusions in garnet, indicating ec-logite-facies metamorphism. Peak metamorphic con-ditions for equilibrium lawsonite-omphacite-phengite- garnet peak assemblages are estimated to be 2.1―2.4 GPa and 420―500℃, which is in the stability field of lawsonite eclogite-facies. A low geotherm of 6―8℃/km is referred, which is in consistent with a cold subduction. The occurrences of lawsonite-bearing eclogites in both NQL and NAT provide further evi-dence that the NAT HP/LT metamorphic belt is pos-sibly the northwestward extension of the NQL HP/LT metamorphic belt offset by the Altyn Tagh left-lateral slip fault. The NQL and NAT lawsonite-bearing ec-logites are formed by subduction of oceanic crust before collision of the Alashan and Qilian blocks in early Paleozoic.

关键词：祁连山阿尔泰山硬柱石榴辉岩洋底壳

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Eclogitic metapelites in the western segment of the north Qaidam Mountains:Evidence on"in situ"relationship between eclogite and its country rock

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Science China Earth Sciences 2004年第12期47卷 1102-1112页

作者： zhang jianxin MENG Fancong YANG Jingsui Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

In Yuka-Luofengpo area of the north Qaidam Mountains, eclogitic metapelites are recognized. The metapelites enclosed lenses of eclogites, and locally intercalated with eclogites. Their typical mineral assemblages are garnet+kyanite+chloritoid+phengite+quartz+rutile. Strong growth zoning is preserved in garnets of metapelites, and phengite contains up to 3.4 Si per formula units. The petrographic observations and textural relations testify to the following sequence of mineral assemblages connected to three metamorphic stage: (1) Grt+ChlI+CldI +PheI ± StI+Qtz; (2) Grt+Ky+PheII±CldII+Qtz; and (3) Grt+CldIII+ChlII+PheIII+StII ± ky+ Qtz. Applying THERMOCALC Program, Grt-Phe thermometer and Grt-Ky-Phe-Qtz barometry, P-T conditions for three metamorphic stages were obtained: P=1.07±0.31GPa, T=564±22? (prograde stage); P=2.3–3.1GPa, T=615–700°C-(peak stage); and P =1.22 ± 0.26GPa, T=581±20°C (retrograde stage). A hairpin shape P-T path similar to that of adjacent eclogite is inferred. In combination with eclogitic mineral relics in marbles and orthogneisses enclosing eclogites, we thought that the relationship between eclogites and country rocks is “in situ” rather than “tectonic emplacement”.

关键词： eclogitic metapelites, in situ, tectonic emplacement.

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The compositional zoning of garnet in eclogite from western segment of Altyn Tagh, northwestern China and its dynamic significance

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Chinese Science Bulletin 2000年第1期45卷 79-83页

作者： zhang Zeming YANG Yong zhang jianxin Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Analyses and Test Center China University of Geosciences(Wuhan)Wuhan 430074China

The eclogites from the Altyn Tagh, northwestern China have been subjected to medium-temperature and high-pressure metamorphism, and then overprinted by the amphibolite to granulite facies retrograde metamorphism, A complex compositionai zoning was well preserved in the garnet porphyroblast formed during the metamorphism of eclogite facies. This zoning recorded P-T path of multistage metamorphism, and an early retrogressive process with features of decreasing pressure and increasing temperature. This evidences a short residence time for the eclogite at peak metamorphism and early retrogression, and thus rapid tectonic uplift history.

关键词： eclogite garnet growth zoning P-7 path exhumation rate Altyn Tagh.

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钢纤维增强碱矿渣再生骨料混凝土的力学性能

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土木与环境工程学报（中英文） 2025年第1期47卷 188-195页

作者：陈庞王政轩张健新王辉史朝悦河北工业大学土木与交通学院天津300401

碱矿渣再生混凝土是以碱激发胶凝材料替代水泥、再生骨料取代天然石子制备而成的新型混凝土,能有效降低波特兰水泥用量,提高废弃混凝土利用率,但尚未见对其力学性能的相关研究。为研究碱矿渣再生混凝土的基本力学性能,以钢纤维取代率和... 详细信息

碱矿渣再生混凝土是以碱激发胶凝材料替代水泥、再生骨料取代天然石子制备而成的新型混凝土,能有效降低波特兰水泥用量,提高废弃混凝土利用率,但尚未见对其力学性能的相关研究。为研究碱矿渣再生混凝土的基本力学性能,以钢纤维取代率和再生骨料取代率为主要试验参数,进行抗压试验、劈裂抗拉试验和抗折试验。研究结果表明:随着再生粗骨料取代率的增加,碱矿渣再生混凝土的抗压强度f_(cu)、劈裂抗拉强度f_(t)和抗折强度f_(w)均降低,再生粗骨料取代率为100%时的降低幅度分别为30%、10%、15%;碱矿渣再生混凝土抗压强度和劈裂抗拉强度随钢纤维体积取代率增加先提高后降低,钢纤维体积取代率为0.6%时,抗压强度和抗折强度达到最大值;碱矿渣再生混凝土抗折强度随钢纤维体积取代率增加而增加。

关键词：再生骨料混凝土抗压强度抗拉强度抗折强度钢纤维体积取代率

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Intelligent self-assembly prodrug micelles loading doxorubicin in response to tumor microenvironment for targeted tumors therapy

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Chinese Journal of Chemical Engineering 2021年第11期34卷 219-227页

作者： Dong Wan Sunfan Li jianxin zhang Guilei Ma Jie Pan School of Chemistry and Chemical Engineering Tiangong UniversityTianjin 300387China The Tianjin Key Laboratory of Biomaterials Institute of Biomedical EngineeringPeking Union Medical College&Chinese Academy of Medical SciencesTianjin 300192China

Compared with physical drug-loaded nanocarriers,polymeric prodrug micelles have many advantages such as high drug loading and enhanced stability in blood,so they have great potential in cancer ***,these micelles have a big disadvantage,which cannot achieve long-term circulation in vivo and high absorption of tumor cells simultaneously,resulting in low administration efficiency and poor therapeutic effect on *** solve problems of traditional polymeric prodrug micelles,novel polymeric micelles with tumor microenvironment response were designed in this *** prodrug formed by covalently linking D-α-tocopherol polyethylene glycol succinate(TPGS_(3350)),peptide(Pep),and doxorubicin(DOX)(TPGS_(3350)-Pep-DOX)was self-assembled into micelles by encapsulating DOX *** the micelles entered the tumor tissue,the long-chain polyethylene glycol(PEG)was sensitively cut by the matrix metalloproteinase 2/9(MMP2/9)enzyme,exposing the targeting molecule folate,then it entered the cell through the endocytic pathway mediated by the folate *** drug loading content,encapsulation efficiency,critical micelle concentration,and invitro release of the micelles invented in this study were measured to characterize their *** particle size and zeta potential of micelles were characterized by dynamic light *** were scanned by transmission electron *** vitro cytotoxicity,cellular uptake,and in vivo antitumor effect evaluation experiments were measured to show that smart micelles have made much progress in material chemistry and drug delivery,making it possible to apply a stimulus-response carrier drug delivery system in clinical application.

关键词： Micelles Drug delivery Tumor Enzyme Polymers Peptide

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Site preference of Ti and Nb in L1-(2)-ordered Co-Al-W phase and their effect on the properties of the alloy:first-principles study

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Communications in Theoretical Physics 2021年第2期73卷 124-130页

作者： Zihan Wang jianxin zhang Pan Li Youjian zhang Huixin Jin Wenyang zhang Key Laboratory for Liquid-Solid Structural Evolution&Processing of Materials(Ministry of Education)School of Materials Science and Engineering Shandong UniversityJipan 250061China

In this work,the equilibrium structure,electronic and elastic properties of L1_(2)-ordered Co-Al-W and Co-Al-W-X(X=Ti and Nb)phase were calculated,using first-principles *** six nonequivalent sites(Al_(1),Al_(2),Co_(3),Co_(4),W_(5),W_(6)),Ti and Nb prefer to occupy the W_(6)site,since the formation enthalpy of the system is lowest when Ti and Nb occupy the W。*** Ti and Nb most affect the density of states of Al *** with the Al_(2) site,which is the sub-preference site of Ti and Nb,the density of states of Al atoms is higher with the addition of Ti and Nb in the W_(6)site,which means that the latter system is more *** to the bulk modulus B,shear modulus G,Young's modulus E,hardness Hv and Poisson's ratioσ,for Co_(3)(AI,W)alloy,the addition of Ti and Nb in the W_(6)site decreases its hardness hut increases its *** work cnnfirms that Ti and Nh can stahilize the Cag(Al,W)alloy and have a positive effect in solving the relatively poor ductility of this alloy,which has important implications for the development of *** alloys.

关键词： Co-Al-W phase equilibrium structure electronic and elastic properties first-principles study

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A Convex Approximation for a PDE Constrained Fractional Optimization Problem with an Application to Photonic Crystal Design

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Advances in Applied Mathematics and Mechanics 2023年第6期15卷 1540-1561页

作者： Mengyue Wu Jianhua Yuan jianxin zhang School of Science Beijing University of Post and TelecommunicationsBeijing 100876China

Based on a subspace method and a linear approximation method,a convex algorithm is designed to solve a kind of non-convex PDE constrained fractional optimization problem in this *** PDE constrained problem is an infinitedimensional Hermitian eigenvalue optimization problem with non-convex and low ***,such a continuous optimization problem can be transformed into a large-scale discrete optimization problem by using the finite element *** use a subspace technique to reduce the scale of discrete problem,which is really effective to deal with the large-scale *** overcome the difficulties caused by the low regularity and non-convexity,we creatively introduce several new artificial variables to transform the non-convex problem into a convex linear semidefinite *** introducing linear approximation vectors,this linear semidefinite programming can be approximated by a very simple linear relaxation ***,we theoretically prove this *** proposed algorithm is used to optimize the photonic band gaps of two-dimensional Gallium Arsenide-based photonic crystals as an *** results of numerical examples show the effectiveness of our proposed algorithm,while they also provide several optimized photonic crystal structures with a desired *** addition,our proposed algorithm provides a technical way for solving a kind of PDE constrained fractional optimization problems with a generalized eigenvalue constraint.

关键词： PDE constrained optimization fractional programming linear approximation finite element method photonic band gap

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