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Mesozoic and Cenozoic uplift and exhumation of the Bogda Mountain,NW China: Evidence from apatite fission track analysis

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Geoscience Frontiers 2015年第4期6卷 617-625页

作者： wenhao tang Zhicheng Zhang Jianfeng Li Ke Li Zhiwen Luo Yan Chen The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Department of Geology School of Earth and Space Sciences Peking University

Apatite fission track （AFT） analysis on samples collected from a Paleozoic series is used to constrain the cooling history of the Bogda Mountain, northwest China. AFT ages range from 136.2 to 85.6 Ma and are younger than rock depositional ages and the mean confined track lengths （11.0 13.2 μm） mostly showing unimodal distribution are shorten, indicating significant track-annealing. Thermal histories modeling based on the distribution of fission-track lengths combined with the regional geological data show that two rapid cooling phases occurred in the latest Jurassic-early Cretaceous and the Oligocene-Miocene. Those new data together with previous published data show that the AFT ages become younger from the southwest to northeast in the western Bogda Mountain and its adjacent areas. The fission-track ages of the southwest area are relatively older （〉100 Ma）, recording the earlier rapid uplift phase during the late Jurassic-Cretaceous, while the ages in the north pied- mont of the Bogda Mountain （namely the northeast part） are younger （〈60 Ma）, mainly reflecting the later rapid uplift phase in the Oligocene-Miocene. The trend of younger AFT ages towards the northeast might be explained by post-Cretaceous large-scale crustal tilting towards the southwest. In the thrust fault-dominated northern limbs of the Bogda Mountain, AFT ages reveal a discontinuous pattern with age-jumps across the major fault zones, showing a possible strata tilting across each thrust faults due to the thrust ramps during the Cenozoic. The two rapid uplift stages might be related to the accretion and collision in the southern margin of the Asian continent during the late Jurassic and late Cenozoic, respectively.

关键词： Apatite fission track Thermal history Exhumation Mesozoic-Cenozoic Bogda Mountain

Geochronology, geochemistry, and its geological significance of the Permian Mandula mafic rocks in Damaoqi, Inner Mongolia

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Science China Earth Sciences 2012年第1期55卷 39-52页

作者： CHEN Chen ZHANG ZhiCheng GUO ZhaoJie LI JianFeng FENG ZhiShuo tang wenhao Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing 100871China

The Hujierte-Chaganhadamiao volcanic-plutonic sequence is located in the Mandula area of northen Damaoqi, Inner Mongo- lia. It contains mainly mafic volcanics, with several ultramafic blocks in its central part and mafic- ntermediate intrusions in the east. The zircon U-Pb ages of the gabbro and basalt samples are 278.5±3.0 Ma （MSWD=）.66） and 273.7±1.0 Ma （MSWD=0.36）, respectively. These ages constrain the magmatism occurred in the Early Permian. The Mandula Permian mafic rocks are characterized by low abundances of REE and slightly LREE-enriched chondrite-normal zed N-MORB-type REE patterns. And these mafic samples have high （143Nd/144Nd）i （0.51262-0.51270）, relatively high pos tive εNd（t）（3.4-8.0）, and high Mg# （49-54）, suggesting derivation from the depleted asthenosphere mantle source. But they al, show the enrichment in large ion lithophile elements （LILE, e.g. Rb, Ba and Sr）, depletion in high field strength elements （I-FSE）; distinctly negative Nb, Ta anomalies and slightly negative P, Ti anomalies; high （875r/86Sr）i （0.70490-0.70537）, low （206pb/204pb）i （17.39-17.93）. All of these resemble the characteristics of the enriched mantle source or involvement of arc materials in the magma genesis. Furthermore, as shown in the correlation plots of eNd（t） VS （87Sr/86Sr）i, （206pb/204Pb）ivs （207pb/204Pb）i and （208pb/204pb）i, La/Ba La/Nb vs La/Nb, and La/Nb ratio, the magma source could have been experienced the contamination and metasomation from the previous subduction process. And the positive correlation between the selected major oxides and trace elements could be explained by the contamination from continental crust and arc materials during the magmatic emplacement. Combined with the distinct geochemistry features of Mandula mafic samples and many previous researches in the study area, the Early Permian magmatism in Mandula occurred under an extensional rift setting, and a juvenile ocean basin probably had already been formed after further development.

关键词： Mandula zircon SHRIMP U-Pb age Permian geochemistry extensional setting

Homovalent doping:An efficient strategy of the enhanced TiNb_(2)O_(7)anode for lithium-ion batteries

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Green Energy & Environment 2024年第8期9卷 1257-1266页

作者： Xiaohe Jin Yirui Deng Han Tian Miaomiao Zhou wenhao tang Huiyou Dong Xinquan Zhang Ruiping Liu Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing100083China

The low energy density,unsatisfied cycling performance,potential safety issue and slow charging kinetics of the commercial lithium-ion batteries restrained their further application in the fields of fast charging and long-haul electric *** TiNb_(2)O_(7)(TNO)with the theoretical capacity of 387 mAh g^(-1)has been proposed as a high-capacity anode materials to replace *** this work,homovalent doping strategy was used to enhance the electrochemical performance of TiNb_(2)O_(7)(TNO)by employing Zr to partial substitute Ti through solvothermal *** doping of Zr^(4+)ions can enlarge the lattice structure without changing the chemical valence of the original elements,refine and homogenize the grains,improve the electrical conductivity,and accelerate the ion diffusion kinetics,and finally enhance the cycle and rate ***,Z0.05-TNO shows initial discharge capacity of as high as 312.2 mAh g^(-1)at 1 C and 244.8 mAh g^(-1)at 10 C,and still maintains a high specific capacity of 171.3 mAh g^(-1)after 800 cycles at 10 *** study provides a new strategy for high-performance fast-charging energy storage electrodes.

关键词： Homovalent doping Zr^(4+)TiNb_(2)O_(7) Microsphere Lithium-ion batteries

Surface engineering for high stable lithium-rich manganese-based cathode materials

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Chinese Chemical Letters 2023年第6期34卷 588-593页

作者： Miaomiao Zhou Jianjun Zhao Xiaodong Wang Ji Shen wenhao tang Yirui Deng Ruiping Liu School of Chemical&Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China State Key Laboratory of Chemical Resources Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringCollege of ChemistryBeijing University of Chemical TechnologyBeijing 100029China Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China

Lithium-rich manganese-based material shows great potential as the high specific cathode materials due to its low cost,environmental friendliness,high operating voltage and simple preparation ***,the poor capacity retention and cycling performance caused by its unstable structure during cycling restrict the *** this work,Li_(1.2)Ni_(0.16)Mn_(0.56)Co_(0.08)O_(2)was synthesized utilizing a Coprecipitation method and different amount of La(PO_(3))_(3)(La(PO_(3))_(3)=2 wt%,4 wt%and 6 wt%)was selected as the coating layer to resolve the above *** the calcination process,La(PO_(3))_(3)reacts with impurities such as Li OH and Li_(2)CO_(3)on the lithium-rich surface to reduce the residual lithium on the surface,thus improving the interfacial stability,slowing down the corrosion of the electrolyte,and finally enhancing its electrochemical *** cathode materials coated with 4%of La(PO_(3))_(3)showed the best electrochemical performance in terms of capacity retention and cycling performance compared to the pristine *** high initial discharge capacity of 214.21 m Ah/g and capacity retention of 94.2%after 100 cycles at 0.1 C can be *** work provides an effective strategy to protect the cathode from corrosion and will promote its further practical applications in high specific Li-ion batteries.

关键词： Li-rich layered oxide Li-ion batteries La(PO_(3))_(3)coating Electrochemical performance Structure stability

Nickel-decorated TiO2 nanotube arrays as a self-supporting cathode for lithium-sulfur batteries

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Frontiers of Materials Science 2020年第3期14卷 266-274页

作者： Yuming Chen wenhao tang Jingru Ma Ben Ge Xiangliang Wang Yufen Wang Pengfei Ren Ruiping Liu Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing100083China Energy&Materials Engineering Center College of Physics and Materials ScienceTianjin Normal UniversityTianjin300387China

Lithium-sulfur batteries are considered to be one of the strong competitors to replace lithium-ion batteries due to their large energy ***,the dissolution of discharge intermediate products to the electrolyte,the volume change and poor electric conductivity of sulfur greatly limit their further ***,we proposed a self-supporting cathode of nickel-decorated TiO2 nanotube arrays(TiO2 NTs@Ni)prepared by an anodization and electrodeposition *** TiO2 NTs with large specific surface area provide abundant reaction space and fast transmission channels for ions and ***,the introduction of nickel can enhance the electric conductivity and the polysulfide adsorption ability of the *** a result,the TiO2 NTs@Ni-S electrode exhibits significant improvement in cycling and rate performance over TiO2 NTs,and the discharge capacity of the cathode maintains 719 mA·h·g−1 after 100 cycles at 0.1 C.

关键词： lithium-sulfur battery TiO2 self-supporting polysulfide intermediate

The key technology of Micro area visualization in the application of the oil and gas exploration and development

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Acta Geologica Sinica(English Edition) 2015年第A1期89卷 405-408页

作者： SUN Xianda tang wenhao YU Xiaodan Exploration and Development Research hlstitute of Daqing Oilfield Company Limited Daqing 163318 China Enhanced Oil Recovery Research Institute China University of Petroleum (Beijing) Beijing 102249 China School of Petroleum and NaturalGas Engineering Southwest Petroleum University Chengdu 610500 China

1 Introduction Micro area visualization technology is one of the most reliable and most intuitive technological means for our engineers on solving difficult reservoir problems. This not only can be clearly definite such as Oil and gas occurrence of geological problems in the process of oil and gas exploration, but also can be solved remaining oil distribution and mechanism of exploitation problems in the process of oil and gas development.

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Microstructure evolution of ATI718 plus alloy during high-speed machining:Experiments and a combined FE-CA approach

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Chinese Journal of Aeronautics 2024年第12期37卷 498-521页

作者： Xuhang GAO Changfeng YAO Liang TAN Minchao CUI wenhao tang Guangyuan SHI Jikang ZHAO Jianxin LUO Ya ZHANG The Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Ministry of EducationNorthwestern Polytechnical UniversityXi’an 710072China

Excellent surface integrity is an eternal pursuit in high performance manufacturing,with microstructure being a crucial component of the surface integrity dataset and a key factor controlling surface properties such as fatigue and *** multi-physical fields generated by thermomechanical loads during high-speed machining act on the processed surface layer,influencing the evolution of *** investigate the microstructural evolution mechanisms of ATI718 plus during high-speed machining,cutting experiments and techniques such as Electron back scatter diffraction(EBSD),Transmission Kikuchi diffraction(TKD),and Precession electron diffraction(PED)is conducted to quantitatively analyze the microstructures in the chip shear zone and the machined ***,a combined finite element(FE)and cellular automata(CA)model is developed to simulate the microstructure evolution during the cutting *** discontinuous dynamic recrystallization(DDRX)mechanism is employed to demonstrate the nucleation and growth of grains under the influence of multiple physical *** simulation and experimental results show similar dynamic recrystallization(DRX)grain sizes,indicating acceptable accuracy of the CA model in terms of DRX grain *** comparison between experimental and simulation results confirms the occurrence of both continuous dynamic recrystallization(CDRX)and DDRX during the cutting *** synergistic competition between CDRX induced grain lamellar refinement and DDRX induced grain growth emerge as the primary mechanism driving microstructural evolution.A layer of ultrafine grains,with a thickness within 20 lm,is formed on the machined *** under different parameters demonstrate that the temperature has a more significant impact on the thickness of the ultrafine grain layer and the diameter of grains within the layer compared to the strain rate.

关键词： Surface integrity Dynamic recrystallization Microstructure evolution Finite element Cellular automata High-speed machining

Co-guiding the dendrite-free plating of lithium on lithiophilic ZnO and fluoride modified 3D porous copper for stable Li metal anode

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Journal of Materiomics 2020年第1期6卷 54-61页

作者： Xinshuang Chang Hang Liu Hang Yang Jie Di wenhao tang Huadong Fu Mingyang Li Ruiping Liu Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

Lithium metal battery is considered to be the most promising energy storage technologies due to its ultra-high theoretical capacity and extremely low standard ***,the infinite volume change during uneven deposition/dissolution process and the growth of lithium dendrite resulting in severe capacity decay and high safety hazards,which hinders the application in next generation secondary *** this paper,the three dimensional(3D)porous copper is prepared through an electrochemical etching CueZn alloy,and the pore walls are modified with lithiophilic layer of ZnO and *** as-prepared 3D Cu/ZnO/F can inhibit the growth of Li dendrite and mitigate the huge volume change of Li metal anode during cycling process,resulting in stable solid electrolyte interface(SEI)layer and electrode *** Li|3D Cu/ZnO/F cell can be stably cycled over 300 cycles with 98% of coulomb efficiency at 0.5 mA cm^(-2),1 mAh cm^(-2).The synergistic effects of both ZnO and fluorine on inducing the uniform deposition of lithium by providing bonding sites can inhibit the generation of lithium dendrites and thus improve the electrochemical performance of lithium metal batteries.

关键词： Lithium metal battery 3D copper Lithium dendrites Modification

Simultaneous bilateral retroperitoneoscopic nephroureterectomy in renal recipients： a single-center experience

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Chinese Medical Journal 2014年第22期127卷 3993-3995页

作者： Ma Lulin Ye Jianfei tang wenhao Department of Urology Peking University Third Hospital Beijing 100191 China

Conventional simultaneous bilateral open nephroureterectomy combined with resection of bladder cuffs seems not optimal for bilateral upper tract urothelial carcinoma （UTUC） in renal transplant and dialysis patients with enormous invasion related to large morbidity,delayed gastrointestinal function,and late recovery.1 This study reports the largest series of minimally invasive procedures of simultaneous bilateral retroperitoneoscopic nephroureterectomy （SBRNU） via a midline lower abdominal incision in renal recipients.

关键词： retroperitoneoscopy bilateral nephroureterectomy urothelial carcinoma renal transplantation