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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.

Genesis of the mega-crystal zircons in the dunite veins of North Qaidam Mountains,northwestern China

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Chinese Science Bulletin 2009年第16期54卷 4688-4696页

作者： meng fancong zhang jianxin Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

A megacrystal zircon occurs in serpentinized dunite veins from North Qaidam, northwestern China. It is red-brown and 3―4 mm long and 2 mm wide in size. BSE imaging shows the presence of micro-grains (30―50 μm) of zircon between olivine and serpentine, part of them gathering into clusters (100―300 μm). Thus we infer that these zircon crystals were precipitated from hydrothermal fluid. Inclusions of baddeleyite (white) in the shape of isolated island locally occur in the large zircon (grey), implying that the former formed earlier than the latter. The mirco-baddeleyite (50―100 μm) aggregate consists of baddeleyite (3―5 μm) and olivine (<5 μm), indicating the zircon formation through interaction between baddeleyite and silica-bearing fluid. Therefore, we consider a genetic link between the formation of the large zircon and the serpentinization of dunite. SHIRIMP U-Pb dating of the large zircon gave two groups of concordant ages at 414 ± 13 Ma and 371 ± 9 Ma, respectively. This might reflect two episodes of zircon growth in response to two episodes of fluid action.

关键词：柴达木锆石中国晶体西北岩脉山区巨型

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Evidence for UHP metamor-phism of eclogites from the Altun Mountains

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Chinese Science Bulletin 2002年第9期47卷 751-755页

作者： jianxin zhang Jingsui Yang Zhiqin Xu fancong meng Haibing Li Rendeng Shi Chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

Ultrahigh pressure (UHP) metamorphism refers to metamorphism that has occurred at pressures for the stability of coesite. The polycrystalline quartz inclusions showing the characteristic texture within garnets of eclogites indicates the pre-existence of coesites under the peak meta-morphic condition. The unusual exsolution textures in om-pacites and apatites, and the pressure estimations of phengite-bearing eclogites have been taken to provide further proof of eclogite formation under the UHP conditions. Combined with the fact that coesites have been observed in country rocks of eclogites in North Qaidam Mountains, another UHP metamorphic belt cut by the large-scale strike-slip fault in the Altun-North Qaidam area of China is confirmed.

关键词： Altun Mountains eclogite UHP metamorphism.

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

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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

2D phosphides heterostructures on titanium microfiltration membrane for enhanced ampere-level current density overall seawater splitting

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Nano Research 2025年第1期18卷 249-259页

作者： Wenjing Dai Xin Wang Yulong Ma Sisi He Ming Chen Zhaohui Yin Shuheng Tian Maolin Wang Shixiang Yu Hang zhang Yuanzhe Wang Hong Wang jianxin Li Faming Gao Bowen Cheng Yun Wang Zhen Yin Ding Ma Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization College of Chemical Engineering and Materials ScienceTianjin University of Science and TechnologyTianjin 300457China State Key Laboratory of Biobased Fiber Manufacturing Technology Tianjin University of Science and TechnologyTianjin 300457China Haian Institute of High-Tech Research Nanjing UniversityHaian 226600China Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Separation Membranes and Membrane Processes Separation Membrane Science and Technology International Joint Research CentreTiangong UniversityTianjin 300387China Centre for Catalysis and Clean Energy School of Environment and ScienceGold Coast CampusGriffith UniversitySouthportQueensland 4222Australia

The advancement of direct seawater electrolysis is a significant step towards sustainable hydrogen production,addressing the critical need for renewable energy sources and efficient resource ***,direct seawater electrolysis has to face several challenges posed by the corrosiveness of highly concentrated chloride and the competitive chlorine evolution reaction(ClER).To overcome these issues,we designed a novel NiP_(2)@CoP electrocatalyst on a porous titanium microfiltration(Ti MF)*** obtained bifunctional NiP_(2)@CoP catalyst outperforms the Pt/C and IrO_(2),as evidenced by its low overpotentials of 192 and 425 mV at a current density of 500 mA·cm^(-2) for hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)in alkaline seawater(1 M KOH+0.5 M NaCl),***,only 231 and 569 mV overpotentials are required at the current density of 1500 mA·cm^(-2) towards HER and OER in alkaline seawater,*** importantly,no ClER was observed,demonstrating its excellent selectivity to *** selection of porous Ti MF membrane as an electrode substrate further enhances the performance by providing a robust structure that promotes the fast generation and release of gas *** promising outcomes obtained with NiP_(2)@CoP catalysts on Ti MF support,therefore,pave the way for the commercial viability of direct seawater electrolysis technologies at industrial-level current densities.

关键词： direct seawater electrolysis porous titanium microfiltration membrane phosphides heterostructures NiP_(2)@CoP electrocatalyst excellent selectivity to oxygen evolution reaction(OER)

First extraction of the proton mass radius and scattering length |αρ0p|from ρ^(0) photoproduction

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Science China(Physics,Mechanics & Astronomy) 2023年第3期66卷 98-103页

作者： Xiao-Yun Wang fancong Zeng Quanjin Wang Li zhang Department of Physics Lanzhou University of TechnologyLanzhou 730050China Lanzhou Center for Theoretical Physics Key Laboratory of Theoretical Physics of Gansu ProvinceLanzhou UniversityLanzhou 730000China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

As it involves the lightest physical states excited from the vacuum by the vector quark current,near-threshold ρ^(0)photoproduction is considered a possible way to research the proton radius and the absolute value of the scattering lengths of the ρ^(0)-proton *** this study,under the assumption of a scalar form factor of dipole form,the value of the proton mass radius is calculated as(0.85±0.06) fm by fitting the differential cross section of the γp→ρ^(0)p reaction at near-threshold *** light vector meson photoproduction,because the exchange of a scalar quark-antiquark pair is not suppressed and should dominate the scalar gluon exchange,the radius we extract from ρ^(0)photoproduction is likely to represent the quark radius of the *** fact may explain why the value obtained in this study is very near the proton charge ***,the absolute value of the ρ^(0)-proton scattering length |αρ^(0)p|=(0.31±0.06) fm is obtained for the first time within the vector meson dominance *** result disobeys the rule that the absolute value of the vector meson and proton scattering length |αVp| increases with the meson’s mass,which can be attributed to treating the ρ^(0)meson as a point in the *** results provide useful theoretical information for an in-depth understanding of proton structure and the proton-vector meson interaction.

关键词： nucleon radius scattering length gravitational form factor meson photoproduction

柴北缘绿梁山早古生代花岗岩浆作用与高温变质作用的同时性

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岩石学报 2008年第7期24卷 1585-1594页

作者：孟繁聪张建新中国地质科学院地质研究所北京100037

采用 SHRIMP 方法获得绿梁山花岗岩的锆石 U-Pb 年龄为430±8Ma(12个测点平均),所有测点的 Tb/U 比值均大于0.1,该年龄代表花岗岩的形成年龄。同时获得部分具有核-幔结构的继承锆石,其核部年龄为475～460Ma,Th/U 比值为0.01～0.02,为典... 详细信息

采用 SHRIMP 方法获得绿梁山花岗岩的锆石 U-Pb 年龄为430±8Ma(12个测点平均),所有测点的 Tb/U 比值均大于0.1,该年龄代表花岗岩的形成年龄。同时获得部分具有核-幔结构的继承锆石,其核部年龄为475～460Ma,Th/U 比值为0.01～0.02,为典型的变质锆石,与围岩片麻岩中的锆石类似,反映了花岗岩与片麻岩之间的成因联系。绿梁山花岗岩属于钙碱性系列,SiO_2含量为65.63%～74.78%,变化较大,属于过铝质岩石,推测其源岩以沉积岩为主。围岩片麻岩以变质沉积岩为主,可能为花岗岩的主要源岩。花岗岩的(^(87)Sr/^(86)Sr)_■为0.71075(t=430Ma),ε_(Nd(430Ma))为-5.5～-4.6,与围岩片麻岩的 Sr-Nd 同位素组成存在较大差别,可能反映了花岗岩形成于高温缺水的环境或者成岩时有地幔物质/年轻地壳物质的加入。花岗岩形成时代与片麻岩变质时代的一致性(430Ma),反映了它们为同一区域构造热事件的产物,是俯冲陆壳发生热松弛的记录。

关键词：花岗岩 SHRIMP锆石地球化学绿梁山柴北缘

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

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