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Acta Geologica Sinica(English Edition) 2011年第1期85卷 211-222页

作者： zhang keliang wei dongping College of Earth Science Graduate University of the Chinese Academy of Sciences Beijing 100049 China

For the purpose of investigating the influence of metastable olivine（MO） phase transformations on both deep seismicity and stagnation of slabs,we constructed a 2-dimensional finite element thermal model for a 120 Ma-old 50°dipping oceanic lithosphere descending at 10 cm/yr with velocity boundary layers,which would mitigate the interference of constant velocity field for the slab. The resulting temperatures show that most of intermediate and deep earthquakes occurring within the Tonga slab are occurring inside the 800℃and 1200℃isotherm,*** elevation of olivine transformation near～410 km and respective persistence of metastable olivine and spinel within the transition zone and beneath 660 km would thus result in bimodal positive,zonal,negative density anomalies,*** results together with the resulting pressure anomalies may reflect the stress pattern of the Tonga slab：（i） slab pull force exerts above a depth of～230 km;（ii） MO existence changes the buoyancy force within the transition zone and facilitates slab stagnation at a depth of 660 km;（iii） as the subducting materials accumulated over 660 km,deepest earthquakes occur due to MO transformation;（iv） a flattened‘slab’ may penetrate into the lower mantle due to the density increment of Sp transformation.

关键词： kinematic thermal model subduction zone velocity boundary layer metastable olivine,double seismic zone finite element method

Global Plate Motions and Their Impact on the Earth's Surface Area Change

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Earthquake Research in China 2010年第3期24卷 344-352页

作者： Cao Shuai zhang keliang wei dongping Laboratory of Computational Geodynamics Graduate University of the Chinese Academy of Sciences Beijing 100049 China

Based on their Euler poles, we calculated the relative velocities between every two plates in the typical global plate motion models, respectively, and estimated the area change along these boundaries. In our calculations, plates on both sides accommodated area changes depending on the boundary types： extensional, convergent or transform, so we can estimate area change of each plate and then globally. Our preliminary results show that the area of the southern hemisphere increased while that of the northern hemisphere decreased over the past I million years, and global area has increased by 26,000km^2 to 36,000km^2, which corresponds to the 160m - 250m increment on the Earth＇s radius if all these area increments are attributed to Earth＇s expansion. Taking the NUVEL-1 model as an example, of the 14 plates in this model, 11 are decreasing, but the global area has increased because of the larger increment amount from Africa, North America and Antarctica. Finally, we also discussed factors affecting the global area change such as subduction zone retreating and back-arc spreading.

关键词： Plate Motions NUVEL-1 Model Pacific Plate Subduction

Heterobimetallic lanthanide tetrahedral cages:Synthesis,design and application for potential multimodal imaging contrast agent

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Journal of Rare Earths 2024年第2期42卷 278-285,I0002页

作者： Yongxiu Li Feng Guo Siwei wei Duofu Li Jun zhang Kai Xu dongping Li Department of Chemistry Nanchang UniversityNanchang330031China Key Laboratory of Functional Molecule Design and Interface Process Anhui Jianzhu UniversityHefei230601China Department of Otolaryngology Head and Neck SurgeryThe Second Affiliated Hospital of Nanchang UniversityNanchang330006China

The construction and functionalization of lanthanide-organic cages have been a research hotspot in coordination *** from the unique luminescent and magnetic properties of lanthanide ions,the potential applications of lanthanide-organic cages in biological imaging applications are promising,but only a few corresponding explorations have been *** rein,we introduced a series of lanthanide tetrahedral cages,(Eu_(n)Gd_(4-n)L_(4))(sol)_8(n=0,1,2,3 and 4,where L=(4,4',4"-tris(4,4,4-trifluoro-1,3-dioxobutyl)-triphenylamine,and sol=dimethyl sulfoxide and methanol),with potential applications in biological *** the good luminescent and magnetic properties of Eu^(3+) and Gd^(3+) ions,Eu_(4)L_(4) and Gd_(4)L_(4) complexes show a high luminescence quantum yield of 29% in DMSO and large longitudinal relaxivity(r_(1)) of 11.4(mmol/L)^(-1)/s at 0.5 T in water containing 1 vol% DMSO,*** heterobimetallic Eu-Gd complexes achieve a dual imaging mode by combining luminescent and magnetic centers in one *** the Gd:Eu ratio increases from 1:3 to 3:1,the r_(1) values increases from 5.33 to 8.64(mmoI/L)^(-1)/s,higher than that of commercial contrast agent Gd-DOTA(3.23(mmol/L)^(-1)/s).Owing to their low toxicity and good cell imaging ability toward ECA 109 cells,the selfassembled Eu-Gd heterobimetallic tetrahedral cages could be potential candidates for the multimodal imaging contrast agent.

关键词： Lanthanide organic cage Luminescence Cell imaging Contrast agents Rare earths

Carbene-Catalyzed Asymmetric Ring-Opening Reaction of Biaryl Lactams to Access Axially Chiral Biaryls

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Chinese Journal of Chemistry 2024年第15期42卷 1734-1740页

作者： Guanjie Wang Guowei Yuan Chenlong wei Ye zhang Haibin Zhu weiqi Yang dongping Shi Xiaoxiang zhang Zhenqian Fu Institute of Advanced Materials Nanjing Tech UniversityNanjingJiangsu 211816China Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources College of Chemical EngineeringNanjing Forestry UniversityNanjingJiangsu 210037China

Axially chiral biaryls represent the most important class of atropisomers,and they widely exist in natural products and biologically active *** also constitute a unique scaffold for chiral ligands and catalysts in organic *** development of synthetic methods to obtain such chiral compounds has received widespread attention,among which catalytically atroposelective ring-opening of configurationally labile compounds represents one of the most attractive *** substrates with strained cyclic structures,such as the renowned Bringmann's lactones,can undergo asymmetric transformation into stable *** advancement primarily relies on metal catalyst combined with well-designed chiral ligands,the approaches utilizing organocatalysis as a critical resolution strategy are notably *** this study,we disclosed a N-heterocyclic carbene(NHC)-catalyzed asymmetric ring-opening reaction of biaryl lactams via direct atroposelective nucleophilic *** optimized bulky carbene catalyst ensures that the reaction can proceed under mild conditions,affording the desired product with good to excellent yields and atroposelectivity.

关键词： N-Heterocyclic carbene Axially chiral biaryls Organocatalysis Ring-opening reactions Dibenzo cyclic lactams Axially chiral amino acids Amide C-N bond activation Atropisomerism Asymmetric catalysis Lactams

Tuning microstructures of TC4 ELI to improve explosion resistance

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Defence Technology（防务技术） 2024年第3期33卷 78-99页

作者： Changle zhang Yangwei Wang Lin Wang Zixuan Ning Guoju Li dongping Chen Zhi-wei Yan Yuchen Song Xucai Wang School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing 100081China State Key Laboratory of Explosive Science and Technology Beijing Institute of TechnologyBeijing 100081China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China School of Aeronautical Engineering Zhengzhou University of AeronauticsHenan ProvinceZhengzhou 450046China Shanxi Jiangyang Chemical Co. Ltd.Shanxi ProvinceTaiyuan 030041China Shandong Institute of Non-metallic Materials Shandong ProvinceJinan 250031China

A reasonable heat treatment process for TC4 ELI titanium alloy is crucial to tune microstructures to improve its explosion ***,there is limited investigation on tuning microstructures of TC4 ELI to improve explosion ***,the current challenge is quantifying microstructural changes'effects on explosion resistance and incorporating microstructural changes into finite element *** work aims to tune microstructures to improve explosion resistance and elucidate their anti-explosion mechanism,and find a suitable method to incorporate microstructural changes into finite element *** this work,we systematically study the deformation and failure characteristics of TC4 ELI plates with varying microstructures using an air explosion test and LS-DYNA finite element *** Johnson-Cook(JC)constitutive parameters are used to quantify the effects of microstructural changes on explosion resistance and incorporate microstructural changes into finite element *** of the heat treatment,one plate has equiaxed microstructure and the other has bimodal *** convex of the plate after the explosion has a quadratic relationship with the charge mass,and the simulation results demonstrate high reliability,with the error less than 17.5%.Therefore,it is feasible to obtain corresponding JC constitutive parameters based on the differences in microstructures and mechanical properties and characterize the effects of microstructural changes on explosion *** bimodal target exhibits excellent deformation *** response of bimodal microstructure to the shock wave may be more intense under explosive *** well-coordinated structure of the bimodal target enhances its resistance to deformation.

关键词： Microstructure Finite element modelling Parameter optimization Failure characteristics Explosion resistance

Zeolite-confined Fe-site Catalysts for the Hydrogenation of CO_(2) to Produce High-value Chemicals

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Chemical Research in Chinese Universities 2024年第1期40卷 78-95页

作者： HAN Xiaoyang XIA Huicong TU weifeng wei Yifan XUE dongping LI Minhan YAN Wenfu zhang Jia-Nan HAN Yi-Fan College of Materials Science and Engineering Zhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Coking Coal Resources Green Exploitation Zhengzhou UniversityZhengzhou450001P.R.China Engineering Research Center of Advanced Functional Material Manufacturing of Ministry of Education School of Chemical EngineeringZhengzhou UniversityZhengzhou450001P.R.China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry and College of Chemistry Jilin UniversityChangchun130012P.R.China State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai200237P.R.China

Zeolite-confined Fe-site catalysts(ZFCs)have emerged as superior materials for sustainably producing high-value chemicals through CO_(2) hydrogenation,owing to their adaptable framework,customizable composition,and thermal *** excel in activating,adsorbing,and converting CO_(2) with remarkable efficiency and consistency in *** has sparked a surge in research interest in recent *** review delves into the latest advancements in CO_(2) catalytic hydrogenation to olefins,alcohols,aromatics,and other liquid hydrocarbons,examining the synthesis,modification tactics,and the correlation between structure and performance across various ***,it underscores the pivotal factors affecting performance and sheds light on the mechanisms behind selectivity control in the CO_(2) hydrogenation process facilitated by *** conclude,it presents pressing challenges and strategic recommendations to inspire the development of high-performance,durable ZFCs for CO_(2) hydrogenation applications.

关键词： Zeolite-confined Fe-site catalyst CO_(2) hydrogenation Modification strategy High-value chemical

Gut commensal metabolite rhamnose promotes macrophages phagocytosis by activating SLC12A4 and protects against sepsis in mice

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Acta Pharmaceutica Sinica B 2024年第7期14卷 3068-3085页

作者： dongping Li Rongjuan wei Xianglong zhang Shenhai Gong Meijuan Wan Fangzhao Wang Jiaxin Li Meiling Chen Ruofan Liu Yantong Wan Yinghao Hong Zhenhua Zeng Peng Gu zhang Wang Kutty Selva Nandakumar Yong Jiang Hongwei Zhou Peng Chen Department of Pathophysiology Guangdong Provincial Key Laboratory of ProteomicsSchool of Basic Medical SciencesSouthern Medical UniversityGuangzhou 510000China Department of Critical Care Medicine Nanfang HospitalSouthern Medical UniversityGuangzhou 510000China Department of Gastroenterology Shenzhen HospitalSouthern Medical UniversityShenzhen 518000China Institute of Ecological Sciences School of Life SciencesSouth China Normal UniversityGuangzhou 510000China Department of Environmental and Biosciences School of BusinessInnovation and SustainabilityKristian IV’s vag 3Halmstad UniversityHalmstad 30004Sweden Microbiome Medicine Center Zhujiang HospitalSouthern Medical UniversityGuangzhou 510000China

Sepsis progression is significantly associated with the disruption of gut ***,the modulatory mechanisms of gut microbiota operating during sepsis are still ***,we investigated how gut commensals impact sepsis development in a pre-clinical *** ligation and puncture(CLP)surgery was used to establish polymicrobial sepsis in *** depleted of gut microbiota by an antibiotic cocktail(ABX)exhibited a significantly higher level of mortality than *** determined by metabolomics analysis,ABX treatment has depleted many metabolites,and subsequent supplementation with L-rhamnose(rhamnose,Rha),a bacterial carbohydrate metabolite,exerted profound immunomodulatory properties with a significant enhancement in macrophage phagocytosis,which in turn improved organ damage and ***,rhamnose binds directly to and activates the solute carrier family 12(potassium-chloride symporter),member 4(SLC12A4)in macrophages and promotes phagocytosis by activating the small G-proteins,Ras-related C3 botulinum toxin substrate1(Rac1)and cell division control protein 42 homolog(Cdc42).Interestingly,rhamnose has enhanced the phagocytosis capacity of macrophages from sepsis *** conclusion,by identifying SLC12A4 as the host interacting protein,we disclosed that the gut commensal metabolite rhamnose is a functional molecular that could promote the phagocytosis capacity of macrophages and protect the host against sepsis.

关键词： Gut microbiota Sepsis Rhamnose SLC12A4 GTP-Rac1 GTP-Cdc42 Macrophage Phagocytosis

Correlation between plate age and layer separation of double seismic zones

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Earthquake Science 2012年第1期25卷 95-101页

作者： keliang zhang and dongping wei State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Key Laboratory of Computational Geodynamics Chinese Academy of SciencesBeijing 100049China College of Earth Science Graduate University of Chinese Academy of SciencesBeijing 100049China

Global seismicity catalogs are sufficient for characterizing double seismic zones （DSZs） in subducting slab and facilitate to estimate layer separation without inconsistent uncertainties as local catalogs. Previous studies have shown the correlation between DSZs layer separation and plate age while correlation for those younger than -60 Ma is suspicious. The lacking of DSZs with layer separation less than 10 km further makes it difficult to precisely estimate such correlation. Thus, we incorporate eight DSZs data determined through local seismicity into globally-determined dataset and reexamine such correlation. The best fitting results show that both a linear model and a square root of plate age can mathematically fit the layer separation well. However, it is difficult to distinguish these two models when plate age is greater than -20 Ma since their difference is less than 2 km. However, if extrapolation is possible, both models should provide physical information that DSZs will not form if there is no subducting lithosphere. As a result, the DSZs cannot be produced until the oceanic lithospheric age becomes greater than 0.9 Ma in the square root model while the linear model gives a misleading result. As such the square root model demonstrates the relationship physically better than the linear one, it still needs further test in the future with more available data, nevertheless, our study might also provide evidence for the suggestion that the plate age is a primary control factor of the DSZs geometry as well as the subducting process which disregards any local tectonic stresses.

关键词： double seismic zone layer separation plate age correlation best fitting

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主被动阻尼减振器对轧机辊系减振特性研究

力学学报 2024年第9期56卷 2713-2730页

作者：徐慧东王义平和东平周碧柳张伟太原理工大学机械与运载工程学院太原030024 先进金属复合材料成形技术与装备教育部工程研究中心太原030024 广西大学土木建筑工程学院南宁530004

轧机的垂直振动是冷轧带钢产品生产效率低下的关键问题所在,严重影响了轧制产品的质量和轧制速度的提高.为提升轧机设备的安全性,同时提高生产的效率和钢材的精度,基于主被动阻尼减振器对轧机辊系的振动特性及减振效果进行了研究.首先,... 详细信息

轧机的垂直振动是冷轧带钢产品生产效率低下的关键问题所在,严重影响了轧制产品的质量和轧制速度的提高.为提升轧机设备的安全性,同时提高生产的效率和钢材的精度,基于主被动阻尼减振器对轧机辊系的振动特性及减振效果进行了研究.首先,考虑主动阻尼控制效应中的分数阶和时滞因素,建立带有主被动阻尼减振器的分数阶时滞垂直非线性振动方程;然后,对建立的数学模型进行稳定性分析,得到主被动阻尼减振器各参数的稳定区域;再者,运用多尺度法求得系统的幅频方程,分析系统的时域特性、频谱特性、主共振特性以及次谐共振特性;而后,对轧机辊系振动响应进行时滞反馈控制,通过获得最优反馈控制增益和最优反馈时滞,将振动系统的振幅、不规则振动及能量消耗达到最优;最后,对静定轧机上工作辊进行了垂直振动控制实验,对比发现理论分析与实验结果基本吻合,结果表明主被动阻尼减振器能够有效抑制轧机辊系的垂直振动并满足设计要求.研究结果为轧机辊系减振器的设计应用及轧机的振动控制提供了参考.

关键词：时滞稳定性谐波共振减振控制轧机辊系

Lattice-Preferred orientations of olivine in subducting oceanic lithosphere derived from the observed seismic anisotropies in double seismic zones

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Earthquake Science 2016年第4期29卷 243-258页

作者： Peng Han dongping wei keliang zhang Zhentian Sun Xiaoya Zhou Key Laboratory of Computational Geodynamics Chinese Academy of Sciences Beijing 100049 China College of Earth Science University of Chinese Academy of Sciences Beijing 100049 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029China Beijing Geotherm Research Institute Beijing 100143 China

Subduction zones can generally be classified into Mariana type and Chilean type depending on plate ages, plate thicknesses, subduction angles, back-arc deformation patterns, etc. The double seismic zones （DSZs） in sub- duction zones are mainly divided into type I and type II which, respectively, correspond to the Mariana type and Chilean type in most cases. Seismic anisotropy is an important parameter characterizing the geophysical fea- tures of the lithosphere, including the subduction zones, and can be described by the two parameters of delay time ~t and fast wave polarization direction ~b. We totally col- lected 524 seismic anisotropy data records from 24 DSZs and analyzed the statistical correlations between seismic anisotropy and the related physical parameters of DSZs. Our statistical analysis demonstrated that the fast wave polarization directions are parallel to the trench strike with no more than 30~ for most type I DSZs, while being nearlyperpendicular to the trench strike for type II DSZs. We also calculated roughly linear correlations that the delay time 6t increases with dip angles but decreases with subduction rates. A linear equation was summarized to describe the strong correlation between DSZ＇s subduction angle DSZ and seismic anisotropy in subduction zones. These results suggest that the anisotropic structure of the subducting lithosphere can be described as a possible equivalent crystal similar to the olivine crystal with three mutually orthogonal polarization axes, of which the longest and the second axes are nearly along the trench-perpendicular and trench-parallel directions, respectively.

关键词： Seismic anisotropy Double seismic zonesSubduction zone processes Plate motions Microstructures