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Petrogenesis and tectonic implications of Late Triassic granitoids in the Alananshan,East Kunlun belt:evidence from geochemistry,geochronology,and zircon Hf isotopic compositions

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Acta Geochimica 2022年第6期41卷 947-967页

作者： zhen xi Huan Li Safiyanu Muhammad Elatikpo Guangming Gao Decheng ma School of Municipal and Geomatics Engineering Hunan City UniversityYiyang413000China School of Geosciences and Info-Physics Central South UniversityChangsha410083China Department of Geology Ahmadu Bello UniversityZariaNigeria No.701 Geological Team Xinjiang Nonferrous Geoexploration BureauChangji831100China

The Qimantag in the East Kunlun Orogenic Belt has widespread Triassic magmatic rocks that have received scant attention,with an unresolved issue relating to its petrogenesis and geodynamics.In this paper,we used zircon U-Pb-Hf isotopes and whole-rock geochemistry to trace the petrogenesis and tectonic settings of the moyite and monzogranite from the Qimantag Alananshan,East Kunlun.The moyite and monzogranite are silicic(SiO_(2-)~69.9-76.41%),highly alkali(Na_(2)O+K_(2)O~7.29 to8.96 wt.%),with Mg^(#)about 10.4-30.34,indicative of a high-K calc-alkaline rock series.The rare earth element patterns diagram is right-leaning,with a negative Eu anomaly(δEu=0.31-0.68).They are enriched in Rb,K,and light rare earth elements but depleted in Nb,Ta,and Ti,with abundant amphibole,typical of I-type granites.U-Pb on zircon constrained the emplacement of the moyite at 223.9±2.6 ma and monzogranite at 226.9±2.9 ma.TheεHf(t)values range from-2.8 to+0.1 except for one outlier value of-7.0,corresponding two-stage model age of 1249-1437 ma.Our combined geochemical and isotopic results indicate that the moyite and monzogranite were derived from partial melting of the lower thicken crust with the contribution from the older basement materials.These rocks formed in a post-collision setting that is transitional between compressive collision and extension orogeny.

关键词： I-type granite Petrogeochemistry Triassic magmatic rocks Hf isotope East Kunlun orogenic belt

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Singular Value Inequalities of matrix Sum in Log-ma jorizations

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Acta mathematica Sinica,English Series 2023年第2期39卷 375-386页

作者： Bo Yan xi Fu zhen ZHANG College of mathematics Inner Mongolia Minzu UniversityTongliao028043China Department of mathematics Nova Southeastern University3301 College Ave.Fort LauderdaleFL33314USA

We show some upper bounds for the product of arbitrarily selected singular values of the sum of two matrices.The results are additional to our previous work on the lower bound eigenvalue inequalities of the sum of two positive semidefinite matrices.Besides,we state explicitly Hoffman’s minimax theorem with a proof,and as applications of our main results,we revisit and give estimates for related determinant inequalities of Hua type.

关键词： Eigenvalue Hoffman minimax theorem Hua determinant inequality log-majorization majorization Minkowski determinant inequality singular value Wielandt minimax theorem

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Research on the steam–gas pressurizer model with Relap5 code

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Nuclear Science and Techniques 2017年第5期28卷 1-8页

作者： Xi-Zhen Ma Hai-Jun Jia Yang Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Tsinghua University Beijing 100084 China

Steam–gas pressurizers are self-pressurizing, and since steam and noncondensable gas are used to sustain their pressure, they experience very complicated thermal–hydraulic phenomena owing to the presence of the latter. A steam–gas pressurizer model was developed using Relap5 code to investigate such a pressurizer's thermal–hydraulic characteristics.The important thermal–hydraulic processes occurring in the pressurizer model include bulk flashing, rainout, wall condensation with noncondensable gas, and interfacial heat and mass transfer. The pressurizer model was verified using results from insurge experiments performed at the massachusetts Institute of Technology. It was found that noncondensable gas was one of the important factors governing the pressure response, and the accuracy of the developed model would change with different mass fractions and types of noncondensable gas.

关键词： Relap5 code Noncondensable gas Heat and mass transfer Steam–gas pressurizer Condensation

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Regulating surface base of LiCoO_(2) to inhibit side reactions between LiCoO_(2) and sulfide electrolyte

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Rare Metals 2023年第12期42卷 4128-4141页

作者： Kai Yang Rong-zheng Tian zhen-Yu Wang Hong-Zhou Zhang Yue ma xi-xi Shi Da-Wei Song Lian-Qi Zhang Ling-Yun Zhu School of materials Science and Engineering Tianjin University of TechnologyTianjin 300384China Guilin Electrical Equipment Scientifie Research Institute Co.Lud Guilin 541004China Key Laboratory of Advanced Energy materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China School of materials Science and Engineering Anhui UniversityHefei 230601China

The interface instability between layered oxide cathode and sulfide electrolyte is a key point affecting the perform ance of sulfide-based all-solid-state lithium batteries.Coating with fast-ionic conductor and constructing core-shell structure can effectively alleviate the interfacial side reactions and improve the interfacial stability between layered oxide and sulfide electrolyte.However,what have been neglected is the surface base(including Li_(2)CO_(3) and LiOH)of layered oxide can also affect the interfacial stability.To clarify this point clearly and improve the interfacial stability,the surface base of LiCoO_(2)(LCO)is regulated and investigated in this work.First,LCO with surface base Li_(2)CO_(3)(LCO@Li_(2)CO_(3))is prepared by the reaction of Co_(3)O_4 and excess Li_(2)CO_(3).Then,the bare LCO is obtained after LCO@Li_(2)CO_(3) is washed with deionized water and calcined again.Besides,LCO with surface base Li_(2)O(LCO@Li_(2)O)is also prepared with the bare LCO and LiOH.As a result,the electrochemical performances of LCO@Li_(2)O are significantly improved and much higher than those of LCO@Li_(2)CO_(3) and the bare LCO electrodes.In particular,LCO@Li_(2)O-2 cathode display the most outstanding electrochemical performances(discharge capacity138.4 mah·g^(-1)at 0.2C,105 mah·g^(-1)at 2C and a capacity retention of 95.4%after 150 cycles at 0.5C).The high discharge capacity and excellent cycle stability of LCO@Li_(2)O electrode confirm the effectiveness of regulating the surface base of layered oxide from Li_(2)CO_(3) to Li_(2)O.The surface base regulating is expected to be a simple but effective strategy to construct the stable interface between the cathode and the sulfide electrolyte of the all-solid-state lithium batteries.

关键词： All-solid-state lithium battery Sulfide electrolyte LiCoO_(2) Surface base Interfacial stability

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Development of a Universal RNA Dual-Terminal Labeling Method for Sensing RNA-Ligand Interactions

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CCS Chemistry 2023年第1期5卷 221-233页

作者： Longhuai Cheng Dejun ma Jie Zhang Xueying Kang Yang Wu Yi Zhao Long Yi zhen xi State Key Laboratory of Elemento-Organic Chemistry Department of Chemical BiologyCollege of ChemistryNational Pesticide Engineering Research CenterCollaborative Innovation Center of Chemical Science and EngineeringNankai UniversityTianjin 300071 State Key Laboratory of Organic-Inorganic Composites and Beijing Key Laboratory of Bioprocess Beijing University of Chemical Technology(BUCT)Beijing 100029 Key Laboratory of Intelligent Information Processing Research Center for Ubiquitous Computing SystemsInstitute of Computing TechnologyChinese Academy of SciencesBeijing 100190

Dual labeling of an RNA can provide Förster resonance energy transfer(FRET)sensors for studying RNA folding,miRNA maturation,and RNA-protein interactions.Here,we report the development of a highly efficient strategy for direct dual-terminal labeling of any RNA of interest.We explored new Michael cycloaddition for facile labeling of 5′-terminal RNA with improved efficiency.Direct chemical tetrazinylation of RNA at the 3′-terminus was achieved with the highly efficient and catalysis-free tetrazine-cycloalkyne ligation.Both single-terminal labeling methods were combined for dual-terminal labeling of an RNA including short hairpin RNA,pre-miRNA,riboswitch,and noncoding RNA.Notably,these dual-labeled RNA-based FRET sensors were used to monitor RNA-ligand interactions in vitro and in live cells.It is anticipated that these universal RNA labeling strategies will be useful to study RNA structures and functions.

关键词： dual labeling Förster resonance energy transfer sensor Michael cycloaddition tetrazinecycloalkyne ligation RNA-ligand interaction

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In-plane Uniaxial Anisotropy and magnetization Reversal Mechanism of FeCo Films by Strip Pattern

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Acta Metallurgica Sinica(English Letters) 2014年第6期27卷 1099-1104页

作者： Xuemeng Han Jinhua ma zhen Wang Yalu Zuo Li xi Key Laboratory for magnetism and magnetic materials of Ministry of Education Lanzhou University

Strip-like Fe Co films were patterned by a traditional lithograph process from intrinsically isotropic continuous Fe Co films. The strip-patterned Fe Co film shows a strong in-plane uniaxial magnetic anisotropy with easy axis along the length direction of the strip. The angular dependences of remanence ratio, switching field, and coercivity indicate that the magnetization reversal mechanism of the strip-patterned Fe Co film is coherent rotation and domain wall depinning when the applied field is near the hard axis and easy axis, respectively. The consistency of the experimental hysteresis loops of the strip-patterned Fe Co film and calculated hysteresis loops with a simple in-plane uniaxial anisotropy model indicates that the strip-patterned Fe Co film behaves as a single domain. The absence of the domain wall and the strong in-plane anisotropy field make the strip-patterned Fe Co films have much potential for high-frequency application.

关键词： In-plane anisotropy Fe Co film Strip patterned Switching field

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Microstructural adjustments and mechanical properties of a cold-rolled biomedical near β-Ti alloy sheet

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Rare Metals 2018年第10期37卷 846-851页

作者： xi-Qun ma Hong-Zhi Niu zhen-Tao Yu Sen Yu Chang Wang Northwest Institute for Nonferrous Metal Research Xi'an 710016 China School of materials Science and Engineering Northeastern University Shenyang 110819 China

In this study, microstructural adjustments and mechanical properties of a cold-rolled near β-type alloy Ti-25Nb-3Zr-3Mo-2Sn （wt%） sheet were investigated. Microstructures and phase transformation products strongly depended on aging temperatures. Solution treatments within single β-phase field removed the stress-induced at martensites and produced a few new lath-shaped ones, but metastable β phase still dominated. This is exactly the reason why current alloy exhibits the lowest modulus （54 GPa） and best elongation to fracture （39 %）, but the worst yield strength of only 340 MPa, at solutiontreated state. A fairly large number of ellipsoidal ω phase nanoparticles precipitated throughout parent β phase during aging at 380℃. These ω nanoparticles possess remarkable strengthening effect, but deteriorate ductility seriously. A novel post-aging process was proposed to remove brittle ω phase. By contrast, aging at 450 ℃ resulted in sufficient precipitation of fine needle-like α phase. This brought about the best combination of high yield strength （770 MPa） and moderate elastic modulus （75 GPa） and good elongation （15 %） for biomedical implants.

关键词： Near β-Ti alloy Microstructures Phase transformation Mechanical properties

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Enhanced red luminescence of Ca_(3)Si_(2−x)M_(x)O_(7):Eu^(3+)(M=Al,P)phosphors via partial substitution of Si^(4+) for applications in white light-emitting diodes

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Rare Metals 2024年第2期43卷 736-748页

作者： Yu-Hao ma xi Gao Wen-Tao Zhang zhen-Rui Yang Zhou Zhao Chen Qu College of materials and Chemistry and Chemical Engineering Chengdu University of TechnologyChengdu610059China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China International Advanced Energy Science Research and Education Center Graduate School of Energy ScienceKyoto UniversityYoshida-HonmachiKyoto606-8501Japan

A red-emitting phosphor Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) with partial Al^(3+)/P^(5+) substitution on Si^(4+) was synthesized via a simple solid-state method,and the effects of the introduction of the M^(3+/5+)(M=Al,P)ions on the crystal structure and photoluminescence performance of Ca_(2.91)Si_(2−x)M_(x)O_(7):0.09Eu^(3+) phosphors were investigated.The X-ray diffraction(XRD),energy-dispersive X-ray spectroscopy(EDS),and X-ray photoelectron spectroscopy(XPS)results revealed that the structure of Ca_(3)Si_(2)O_(7) remained the same after the introduction of Al^(3+) and P^(5+) ions.The characteristic emission of Eu^(3+)-doped Ca_(3)Si_(2−x)M_(x)O_(7) phosphors exhibited two main peaks at 617 nm(red)and 593 nm(orange)under excitation at 394 nm,which originated from the^(5)D_(0)→^(7)F_(2)and^(5)D_(0)→^(7)F_(1) electron transitions of Eu^(3+) ions.After the partial substitution of Al^(3+) and P^(5+),the red emission intensities of the Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) phosphors were significantly enhanced by 1.88-and 1.42-fold,respectively,which is attributed to the crystal-field effect around Eu^(3+).Meanwhile,the luminescence intensities of the Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+) and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) phosphors at 210℃ were 79.36%and 77.53%of those at 30°C,respectively,indicating their excellent thermal stability.Moreover,the as-prepared Ca_(2.91)Si_(1.96)Al_(0.04)O_(7):0.09Eu^(3+)and Ca_(2.91)Si_(1.94)P_(0.06)O_(7):0.09Eu^(3+) red-emitting phosphors were combined with a near-ultraviolet chip of 395 nm to fabricate red-light-emitting diode(LED)and white(w)-LED devices with excellent chromaticity features.In summary,Al^(3+)/P^(5+)-substituted Ca_(2.91)Si_(2)O_(7):0.09Eu^(3+) can serve as red-emitting phosphors for applications in w-LEDs.

关键词： Ca_(3)Si_(2)O_(7) Red-emitting phosphor Structure substitution Luminescence enhancement Crystal-field effect White light-emitting diode

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A Lindqvist-type [W_(6)O_(19)]^(2-) organic–inorganic compound: synthesis, characterization, antibacterial activity and preliminary studies on the mechanism of action

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Tungsten 2022年第2期4卷 121-129页

作者： Meng Zhao xi-Yu Zhu Yan-zhen Li Jiang-Nan Chang Ming-Xue Li Li-Hua ma xiao-Yuan Guo Henan Key Laboratory of Polyoxometalate Chemistry Institute of Molecular and Crystal EngineeringSchool of Chemistry and Chemical EngineeringHenan UniversityKaifeng475004China Agricultural Products’Quality and Safety Testing Center of Kaifeng Kaifeng Agriculture and Rural BureauHenan475004China

In this paper,a new organic–inorganic hybrid compound[Co(L)_(2)]2[W_(6)O_(19)](1)(HL=2-acetylpyridine thiosemicarbazone)was prepared and characterized.The compound 1 exhibits remarkable antibacterial activity by determination of minimum inhibitory concentration(MIC)against Staphylococcus aureus(S.aureus,0.06μg·mL^(−1))and Escherichia coli(E.coli,0.24μg·mL^(−1)),respectively.Furthermore,the potential mechanism of compound 1 was studied in detail.The potential causes of bacteria death were cell wall/membrane disruption,inhibition of intracellular respiratory chain dehydrogenases(RCD)activity,destruction of reactive oxygen species(ROS)and depletion of glutathione(GSH).

关键词： Isopolytungstate Thiosemicarbazone Bioactivity Mechanism of action

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How precipitation and grazing influence the ecological functions of drought-prone grasslands on the northern slopes of the Tianshan Mountains, China?

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Journal of Arid Land 2021年第1期13卷 88-97页

作者： HUANG xiaotao LUO Geping CHEN Chunbo PENG Jian ZHANG Chujie ZHOU Huakun YAO Buqing ma zhen xi xiaoyan Qinghai Provincial Key Laboratory of Restoration Ecology for Cold Regions Northwest Institute of Plateau BiologyChinese Academy of SciencesXining 810008China Key Laboratory of Adaptation and Evolution of Plateau Biota Chinese Academy of SciencesXining 810008China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China xinjiang Grassland Technical Popularization Station Urumqi 830049China Qinghai Environmental Sciences Research and Design Institute Co.Ltd. Xining 810007China

Drought-prone grasslands provide a critical resource for the millions of people who are dependent on livestock for food security.However,this ecosystem is potentially vulnerable to climate change(e.g.,precipitation)and human activity(e.g.,grazing).Despite this,the influences of precipitation and grazing on ecological functions of drought-prone grasslands in the Tianshan Mountains remain relatively unexplored.Therefore,we conducted a systematic field investigation and a clipping experiment(simulating different intensities of grazing)in a drought-prone grassland on the northern slopes of the Tianshan Mountains in China to examine the influences of precipitation and grazing on aboveground biomass(AGB),soil volumetric water content(SVWC),and precipitation use efficiency(PUE)during the period of 2014–2017.We obtained the meteorological and SVWC data using an HL20 Bowen ratio system and a PR2 soil profile hydrometer,respectively.We found that AGB was clearly affected by both the amount and seasonal pattern of precipitation,and that PUE may be relatively low in years with either low or excessive precipitation.The PUE values were generally higher in the rapid growing season(April–July)than in the entire growing season(April–October).Overall,moderate grazing can promote plant growth under water stress conditions.The SVWC value was higher in the clipped plots than in the unclipped plots in the rapid growing season(April–July),but it was lower in the clipped plots than in the unclipped plots in the slow growing season(August–October).Our findings can enhance the understanding of the ecological effects of precipitation and grazing in drought-prone grasslands and provide data that will support the effective local grassland management.

关键词： climate change human activity aboveground biomass precipitation use efficiency soil volumetric water content water stress

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