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The occurrence phases and enrichment mechanism of rare earth elements in cobalt-rich crusts from Marcus-Wake Seamounts

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Acta Oceanologica Sinica 2024年第8期43卷 58-68页

作者： Jingjing Gao Jihua Liu Hui Zhang Shijuan Yan Xiangwen Ren Quanshu Yan Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China

To explore the occurrence phases and enrichment mechanism of rare earth elements(REEs)in cobalt-rich crusts,this study analyzes the mineral composition and REE contents of the samples from Marcus-Wake Seamounts by XRD,ICP-OES and *** results show that,(1)the cobalt-rich crusts contain the major crystalline mineral(vernadite),the secondary minerals(quartz,plagioclase and carbonate fluorapatite),and a large amount of amorphous ferric oxyhydroxides(FeOOH).(2)The cobalt-rich crusts contains higher Mn(10.83%to 28.76%)and Fe(6.14%to 18.86%)relative to other elements,and are enriched in REEs,with total REE contents of 1563−3238μg/g and Ce contents of 790−1722μg/*** earth element contents of the old crusts are higher than those of the new ***,the non-phosphatized crusts have positive Ce and negative Y anomalies,and yet the phosphatized crusts have positive Ce and positive Y anomalies,indicating that cobalt-rich crusts is hydrogenetic and REEs mainly come from seawater.(3)Analytical data also show that the occurrence phases of elements in cobalt-rich crusts are closely related to their mineral *** the non-phosphatized crusts,REEs are adsorbed by colloidal particles into the crusts(about 67%of REEs in the Fe oxide phase,and about 17%of REEs in the Mn oxide phase).In contrast,in the phosphatized crusts(affected by the phosphatization),REEs may combine with phosphate to form rare earth phosphate minerals,and about 64%of REEs are enriched in the residual phase containing carbonate fluorapatite,but correspondingly the influence of Fe and Mn oxide phases on REEs enrichment is greatly *** addition,the oxidizing environment of seawater,high marine productivity,phosphatization,and slow growth rate can promote the REE *** study provides a reference for the metallogenesis of cobalt-rich crusts in the Pacific.

关键词： cobalt-rich crusts REEs occurrence phase enrichment mechanism Marcus-Wake Seamounts

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Solvent effects and potential of mean force study of the SN2 reaction of CH3F+CN-in water

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Chinese Physics B 2018年第3期27卷 238-243页

作者： Chen Li Peng Liu Yongfang Li Dunyou Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

We used a combined quantum mechanics and molecular mechanics （QM/MM） method to investigate the solvent effects and potential of mean force of the CH3F＋CN- reaction in water. Comparing to gas phase, the water solution substantially affects the structures of the stationary points along the reaction path. We quantitatively obtained the solvent effects＇ contributions to the reaction： 1.7 kcal/mol to the activation barrier and -26.0 kcal/mol to the reaction free energy. The potential mean of force calculated with the density functional theory/MM theory has a barrier height at 19.7 kcal/mol, consistent with the experimental result at 23.0 kcal/mol; the calculated reaction free energy at -43.5 kcal/mol is also consistent with the one estimated based on the gas-phase data at -39.7 kcal/mol.

关键词： transition state quantum mechanics and molecular mechanics solvent effect potential of mean force

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Combined multi-level quantum mechanics theories and molecular mechanics study of water-induced transition state of OH^- + CO_2 reaction in aqueous solution

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Chinese Physics B 2017年第10期26卷 200-204页

作者：李琛牛美兴刘鹏李永方王敦友 College of Physics and Electronics Shandong Normal University

The presence of a solvent interacting with a system brings about qualitative changes from the corresponding gas-phase reactions. A solvent can not only change the energetics along the reaction pathway, but also radically alter the reaction mechanism. Here, we investigated the water-induced transition state of the OH^-＋CO2→HCO3^- reaction using a multi-level quantum mechanics and molecular mechanics method with an explicit water model. The solvent energy contribution along the reaction pathway has a maximum value which induces the highest energy point on the potential of mean force. The charge transfer from OH^- to CO2 results in the breaking of the OH^- solvation shell and the forming of the CO2 solvation shell. The loss of hydrogen bonds in the OH^- solvation shell without being compensated by the formation of hydrogen bonds in the CO2 solvation shell induces the transition state in the aqueous solution. The calculated free energy reaction barrier at the CCSD（T）/MM level of theory, 11.8 kcal/mol, agrees very well with the experimental value, 12.1 kcal/mol.

关键词： transition state reaction pathway free energy barrier solvent effect

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Photocatalytic H2 Evolution on TiO2 Assembled with Ti3C2 MXene and Metallic 1T-WS2 as Co-catalysts

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Nano-Micro Letters 2020年第1期12卷 63-74页

作者： Yujie Li Lei Ding Shujun Yin Zhangqian Liang Yanjun Xue Xinzhen Wang Hongzhi Cui Jian Tian School of Materials Science and Engineering Shandong University of Science and Technology

The biggest challenging issue in photocatalysis is efficient separation of the photoinduced carriers and the aggregation of photoexcited electrons on photocatalyst’s *** this paper,we report that double metallic co-catalysts Ti3C2 MXene and metallic octahedral(1T)phase tungsten disulfide(WS2)act pathways transferring photoexcited electrons in assisting the photocatalytic H2 ***2 nanosheets were in situ grown on highly conductive Ti3C2 MXenes and 1T-WS2 nanoparticles were then uniformly distributed on TiO2@Ti3C2 ***,a distinctive 1T-WS2@TiO2@Ti3C2 composite with double metallic co-catalysts was achieved,and the content of 1T phase reaches 73%.The photocatalytic H2 evolution performance of 1T-WS2@TiO2@Ti3C2 composite with an optimized 15 wt%WS2 ratio is nearly 50 times higher than that of TiO2 nanosheets because of conductive Ti3C2 MXene and 1T-WS2 resulting in the increase of electron transfer ***,the 1T-WS2 on the surface of TiO2@Ti3C2 composite enhances the Brunauer–Emmett–Teller surface area and boosts the density of active site.

关键词： Photocatalytic H2 production Ti3C2 MXene Octahedral phase WS2 TiO2 nanosheets Co-catalysts

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Neuroprotective Effects of Molecular Hydrogen:A Critical Review

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Neuroscience Bulletin 2021年第3期37卷 389-404页

作者： Wei Chen Han-Ting Zhang Shu-Cun Qin taishan Institute for Hydrogen Biomedicine Shandong First Medical University and Shandong Academy of Medical SciencesTai'an 271000China Key Laboratory of Atherosclerosis in Universities of shandong and Institute of Atherosclerosis Shandong First Medical University and Shandong Academy of Medical SciencesTai’an 271000China Departments of Neuroscience and Behavioral Medicine and Psychiatry Rockefeller Neurosciences InstituteWest Virginia University Health Sciences CenterMorgantownWV 26506USA

Molecular hydrogen(H_(2))is a physiologically inert ***,during the last 10 years,increasing evidence has revealed its biological functions under pathological *** specifically,H_(2) has protective effects against a variety of diseases,particularly nervous system disorders,which include ischemia/reperfusion injury,traumatic injury,subarachnoid hemorrhage,neuropathic pain,neurodegenerative diseases,cognitive dysfunction induced by surgery and anesthesia,anxiety,and *** addition,H_(2) plays protective roles mainly through anti-oxidation,anti-inflammation,antiapoptosis,the regulation of autophagy,and preservation of mitochondrial function and the blood-brain ***,H_(2) is easy to use and has neuroprotective effects with no major side-effects,indicating that H_(2) administration is a potential therapeutic strategy in clinical *** we summarize the H_(2) donors and their ***,we review the effectiveness and safety of H_(2) in the treatment of various nervous system diseasesbased on preclinical and clinical studies,leading to the conclusion that H_(2) can be a simple and effective clinical therapy for CNS diseases such as ischemia-reperfusion brain injury,Parkinson's disease,and diseases characterized by cognitive *** potential mechanisms involved in the neuroprotective effect of H_(2) are also analyzed.

关键词： Molecular hydrogen(H_(2)) Neurological disease Neuroprotection Anti-oxidation Anti-inflammation Anti-apoptosis

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Synthesis of porous few-layer carbon nitride with excellent photocatalytic nitrogen fixation

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Journal of Materiomics 2020年第1期6卷 128-137页

作者： Yanjun Xue Xiangkun Kong Yichen Guo Zhangqian Liang Hongzhi Cui Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao266590China

The porous few-layer g-C_(3)N_(4)(PFL-g-C_(3)N_(4))is prepared by a simple molecular self-assembly *** with pure g-C_(3)N_(4),the as-prepared PFL-g-C_(3)N_(4) is ultrathin,the surface is rich in pores,and the photocatalytic nitrogen fixation activity is greatly increased to 8.20 mM h^(-1) gCat^(-1).Few-layer and ultrathin nature of PFL-g-C_(3)N_(4) can provide a larger specific surface area,expose more active sites,and reduce the diffusion path of charges and protons from the inside to the *** addition,the porous structure can narrow the band gap,thereby increasing the light absorption range and enhancing the light absorption ***,the presence of nitrogen vacancies causes PFL-g-C_(3)N_(4) to move to a more negative conductive band *** importantly,the isotopic experiments using ^(15)N_(2) as nitrogen source confirm the ammonia production originating from N2 rather than the decomposition of g-C_(3)N_(4).Therefore,PFL-g-C_(3)N_(4) can greatly improve the efficiency of visible light photocatalytic nitrogen fixation.

关键词： Molecular self-assembly g-C_(3)N_(4) Porous structure Nitrogen vacancies Photocatalytic nitrogen fixation

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A general synthesis of inorganic nanotubes as high-rate anode materials of sodium ion batteries

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Journal of Energy Chemistry 2023年第2期77卷 369-375,I0010页

作者： Chunting Wang Ningyan Cheng Zhongchao Bai Qinfen Gu Feier Niu Xun Xu Jialin Zhang Nana Wang Binghui Ge Jian Yang Yitai Qian Shixue Dou Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinan 250100ShandongChina Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601AnhuiChina College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina Australian Synchrotron 800 Blackburn RoadClaytonVIC 3168Australia College of Chemistry and Materials Engineering Anhui Science and Technology UniversityBengbu 233000AnhuiChina Institute for Superconducting and Electronic Materials University of Wollongong Innovation Campus Innovation Campus Squires WayWollongongNew South Wales 2500Australia Institute of Energy Materials Science(IEMS) University of Shanghai for Science and TechnologyShanghai 200093China

Ino rganic tubular materials have an exceptionally wide range of applications,yet developing a simple and universal method to controllably synthesize them remains *** this work,we report a vaporphase-etching hard-template method that can directly fabricate tubes on various thermally stable oxide and sulfide *** synthesis method features the introduction of a vapor-phase-etching process to greatly simplify the steps involved in preparing tubular materials and avoids complicated postprocessing ***,the in-situ heating transmission electron microscopy(TEM)technique is used to observe the dynamic formation process of TiO_(2-x) tubes,indicating that the removal process of the Sb2S3 templates first experienced the Rayleigh instability,then vapor-phase-etching *** used as an anode for sodium ion batteries,the TiO_(2-x) tube exhibits excellent rate performance of134.6 mA h g^(-1) at the high current density of 10 A g^(-1) and long-term cycling over 7000 ***,the full cell demonstrates excellent cycling performance with capacity retention of 98%after 1000 cycles,indicating that it is a promising anode material for *** method can be expanded to the design and synthesis of other thermally-stable tubular materials such as ZnS,MoS_(2),and SiO_(2).

关键词： Tubular materials In-situ heating TEM Sodium ion batteries TiO_(2) Hard template methods

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Ab initio Molecular Dynamics Study of Adsorption of Hydroxyl Groups on Graphene Surface

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Chinese Journal of Chemical Physics 2021年第6期34卷 777-784,I0003,I0056-I0060页

作者： Hong-de Liu Nai-gui Liu Dun-you Wang Jun-feng Ren College of Physics and Electronics Shandong Normal UniversityJinan 250014China

Reduced graphene oxide is the precursor to produce graphene in a large scale;however,to date,there has been no consensus on the electronic structure of reduced graphene *** this study,we carried out an ab initio molecular dynamics simulation to investigate the adsorption process of hydroxyl groups on graphene *** the adsorption process,the OH group needs to firstly pass through a physical adsorption complex with the OH above the bridge site of two carbon atoms,next to surmount a transition state,then to be adsorbed at the atop site of a carbon *** a 5×5 graphene surface,up to 6 hydroxyl groups can be adsorbed on the graphene surface,indicating the concentration coverage of the hydroxyl groups on graphene surface is about 12%.The simulation results show that the negative adsorption energy increases linearly as the number of adsorbed hydroxyl groups increases,and the band gap also increases linearly with the number of adsorbed hydroxyl groups.

关键词： Ab initio molecular dynamics Reaction profile Transition state Adsorption energy Band gap Hydroxyl group

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从头算分子动力学研究H_(2)在缺陷石墨烯负载的Cu_(19)团簇上解离吸附

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Chinese Journal of Chemical Physics 2023年第6期36卷 747-754,I0057页

作者：刘乃贵高得鲁王敦友山东师范大学物理与电子科学学院济南250014

本文运用从头算分子动力学方法研究了H_(2)在Cu_(19)团簇和缺陷石墨烯负载Cu_(19)团簇上的解离吸附.分子水平上的动力学轨迹表明,氢气在Cu_(19)上解离吸附的最佳位点是桥位-空位,两个氢原子吸附在Cu原子两边的桥位和空位上,吸附能为-0.7... 详细信息

本文运用从头算分子动力学方法研究了H_(2)在Cu_(19)团簇和缺陷石墨烯负载Cu_(19)团簇上的解离吸附.分子水平上的动力学轨迹表明,氢气在Cu_(19)上解离吸附的最佳位点是桥位-空位,两个氢原子吸附在Cu原子两边的桥位和空位上,吸附能为-0.74 eV.在缺陷石墨烯负载的Cu_(19)团簇上,两个氢原子的最佳吸附位置是吸附在两个空位上,吸附能为-1.27 eV.总的来说,缺陷石墨烯负载Cu_(19)团簇上的平均吸附能为-1.07 eV,比Cu_(19)团簇上的-0.58 eV多约84%,这表明缺陷石墨烯负载Cu_(19)簇上对于氢气的解离吸附能力大大增强.d带中心向费米能级靠近解释了为什么缺陷石墨烯负载Cu_(19)团簇吸附能力更强.积分晶体轨道哈密顿布居分析表明,与Cu_(19)团簇相比,在缺陷石墨烯支持的Cu_(19)簇上,氢原子与其键合的Cu原子之间更强的键相互作用导致了更大的吸附能.

关键词：氢气的解离吸附从头算分子动力学吸附能密度泛函理论

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Source Lithology and Magmatic Processes Recorded in the Mineral of Basalts from the Parece Vela Basin

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 1991-2006页

作者： YUAN Long YAN Quanshu College of Earth Science and Engineering Shandong University of Science and TechnologyQingdaoShandong 266590China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266061China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdaoShandong 266061China

Since the Early Cenozoic,the Philippine Sea Plate(PSP)has undergone a complex tectonic *** this period the Parece Vela Basin(PVB)was formed by seafloor spreading in the back-arc region of the proto-Izu-Bonin-Mariana(IBM)***,until now,studies of the geological,geophysical,and tectonic evolution of the PVB have been *** this study,we obtained in situ trace element and major element compositions of minerals in basalts collected from two sites in the southern part of the *** results reveal that the basalts from site CJ09-63 were likely formed via~10%partial melting of spinel-garnet lherzolite,while the basalts from site CJ09-64 were likely formed via 15%–25%partial melting of garnet *** order of mineral crystallization for the basalts from site CJ09-64 was olivine,spinel,clinopyroxene,and plagioclase,while the plagioclase in the basalts from site CJ09-63 crystallized earlier than the *** a plagioclase-liquid hygrometer and an olivine-liquid oxybarometer,we determined that the basalts in this study have high H2O contents and oxygen fugacities,suggesting that the magma source of the Parece Vela basalts was affected by subduction components,which is consistent with the trace element composition of whole rock.

关键词： source lithology magmatic processes subduction components back-arc basin basalts Parece Vela Basin

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