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300 MPa grade highly ductile biodegradable Zn-2Cu-(0.2-0.8)Li alloys with novel ternary phases

Journal of Materials Science & Technology 2023年第26期157卷 234-245页

作者： Meng Cao Zhe Xue Zhao-Yong lv Jin-Ling Sun Zhang-Zhi Shi Lu-Ning Wang Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advance Metals and MaterialsSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China Orthopedics Department Peking University ShouGang HospitalBeijing 100144China Advanced Technology and Materials Co. Ltd.(AT&M)Beijing 100081China Liaocheng People’s Hospital Liaocheng Hospital Affiliated to Shandong First Medical UniversityLiaocheng 252000China

Although a few high-strength biodegradable Zn alloys with yield strengths(YSs)over 300 MPa in rolled state have been developed,their elongations(ELs)are generally less than 30%.This study developed rolled Zn-2Cu-x Li(x=0.2 wt.%,0.5 wt.%,0.8 wt.%)alloys with YSs of 316-335 MPa and ELs of 44%-61%.Three-dimensional atom probe(3DAP)and time of flight secondary ion mass spectrometry(TOF-SIMS)were employed to characterize Li distribution.Three kinds of Zn-Cu-Li ternary phases are identified,which are blockyε′-(Cu_(0.5),Li_(0.5))Zn 4,blockyβ′-(Li_(0.9),Cu_(0.1))Zn 4,and small roundγparticles with high Li content in the annealed state.Other identified phases are Zn,β-LiZn 4,andε-CuZn 4 phases.With the increase of Li content in the alloys,ε′phase with 6.50 at.%Cu transforms intoβ′phase with 2.12 at.%Cu,i.e.,the average level in the alloys.Withinε′phase,there exist nano-scale Li clusters andεphase,resulting inε′/εstructure.Dense Zn laths precipitate fromβ′phase,resulting inβ′/Zn lamellar structure.The lamel-lar structure is the matrix of Zn-2Cu-0.8Li and leads to near-isotropic plasticity.Electrochemistry tests show that degradation rates fall in the range of 153-196μm/year,which decrease with Li content.All the alloys exert positive effects on the growth of MC3T3-E1 cells with 10%extract.This research reveals how microstructure evolves in Zn-2Cu-x Li alloys,which lays the foundation for their future applications.

关键词： Biodegradable Zn alloys Zn-Cu-Li ternary phase Microstructure

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Risk Evaluation of Ammonia Leakage based on Modified Probability Calculation Formulas

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Journal of Thermal Science 2023年第2期32卷 854-865页

作者： GE Yingying YANG zhao HE Hongxia WU Xiaokun CHEN Yubo lv Zijian ZHANG yong Key Laboratory of Efficient Utilization of Low and Medium Grade Energy MOESchool of Mechanical EngineeringTianjin UniversityTianjin 300072China State Key Laboratory of Air-Conditioning Equipment and System Energy Conservation GREE Electric AppliancesInc.of ZhuhaiGuangdong 519070China

Due to its flammable,explosive,and corrosive characteristics,fire,and explosion accidents caused by ammonia leakage occur from time to time.In this work,the concentration distribution of the model was calculated according to the existing formula of probabilistic risk assessment.Using the revised formulas,the leakage of the ammonia room was quantitatively analyzed,and different state parameters were analyzed to find out the dangerous leakage points of the ammonia refrigeration system.The results of the calculation are that the existence of obstacles in the space will increase the probability of leakage risk.And the greater the leakage time to the lower flammability limit accounts for the total leakage time,the greater the risk probability.Dangerous leakage in ammonia systems mainly occurs in storage tanks and condensers.The data show that the dynamic mass flow of ammonia leakage decreases with time,and the leakage diameter increases with the increase of leakage pressure.At the same time,the leakage mass increases gradually with the leakage aperture near circular.

关键词： flammable refrigerants leakage risk evaluation of fire probability calculation

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MRI insight on multiphase flow in hydrate-bearing sediment and development mechanism of hydrate seal

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Petroleum Science 2023年第6期20卷 3854-3864页

作者： Guo-Jun zhao Ming-Jun Yang Xin lv Jia-Nan Zheng yong-Chen Song Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of TechnologyDalian 116024LiaoningChina CNOOC Research Institute Co.Ltd Beijing100027China Shanghai Institute for Advanced Study Zhejiang UniversityShanghai201203China

Gas and water migration through the hydrate-bearing sediment are characteristic features in marine gas hydrate reservoirs worldwide.However,there are few experimental investigations on the effect of water-gas flow on the gas hydrate reservoir.In this study,gas-water migration in gas hydrate stability zone(GHSZ)was investigated visually employing a high-resolution magnetic resonance imaging(MRI)apparatus,and the formation of hydrate seal was experimentally investigated.Results revealed that normal flow of gas-water at the low flow rate of 1–0.25 mL/min will induce the hydrate reformation.Conversely,higher gas-water flow rates(at 2–0.5 and 4–1 mL/min)need higher reservoir pressure to induce the hydrate reformation.In addition,the hydrate reformation during the gas-water flow process produced the hydrate seal,which can withstand an over 9.0 MPa overpressure.This high overpressure provides the development condition for the underlying gas and/or water reservoir.A composite MRI image of the whole hydrate seal was obtained through the MRI.The pore difference between hydrate zone and coexistence zone produces a capillary sealing effect for hydrate seal.The hydrate saturation of hydrate seal was more than 51.6%,and the water saturation was more than 19.3%.However,the hydrate seal can be broken through when the overpressure exceeded the capillary pressure of the hydrate seal,which induced the sudden drop of reservoir pressure.This study provides a scientific explanation for the existence of high-pressure underlying gas below the hydrate layer and is significant for the safe exploitation of these common typical marine hydrate reservoirs.

关键词： Gas hydrate Gas-water migration Underlying gas Hydrate seal Pore difference MRI

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Simulation of Elastic and Fatigue Properties of Epoxy/SiO_(2) Particle Composites through Molecular Dynamics

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Computer Modeling in Engineering & Sciences 2021年第7期128卷 339-357页

作者： Gaoge zhao Jianzhong Chen yong lv Xiaoyu Zhang Li Huang Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan430070China

The influence of different nanoparticle sizes on the elastic modulus and the fatigue properties of epoxy/SiO_(2) nanocomposite is studied in this paper.Here,the cross-linked epoxy resins formed by the combination of DGEBA and 1,3-phenylenediamine are used as the matrix phase,and spherical SiO_(2) particles are used as the reinforcement phase.In order to simulate the elastic modulus and long-term performance of the composite material at room temperature,the simulated temperature is set to 298 K and the mass fraction of SiO_(2) particles is set to 28.9%.The applied strain rate is 109/s during the simulation of the elastic modulus.The results show that the elastic modulus of the material increases with the increase in particle size.Furthermore,fatigue simulation under strain control is performed on the model with SiO_(2) nanoparticle radius of 12˚A.The results indicate that the influence trend of variable frequencies on the fatigue mechanical response is similar,and the mean stress decreases with the increase in number of cycles.In addition,the smaller the loading period and the more the number of cycles,the greater the mean stress reduction.Finally,the change in energy and free volume fraction are evaluated under fatigue loading condition.

关键词： SiO_(2)particle elastic modulus fatigue free volume molecular dynamics

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The effect of metal ions with different valences on the retardation of soil–bentonite barrier materials and its mechanism

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Chinese Chemical Letters 2013年第12期24卷 1075-1079页

作者： Shu-Qing lv yong-Sheng zhao Key Laboratory of Groundwater Resources and Environment Ministry of Education Jilin University

In this paper, with K＋, Ca2＋ and Fe3＋ as the objects of study, retardation of soil-bentonite （SB） barrier materials for metal ions with different valences is investigated, and the adsorption mechanism, migration patterns and permeation behavior are explored so as to provide a theoretical basis for their application. The results show that the adsorption process for metal ions with different valences by SB barrier materials is fast, and the higher the valence, the greater the adsorption capacity. The fitting of the adsorption process conforms to pseudo-second-order adsorption kinetics and Langmuir-Freundlich adsorption equation, which explains that chemical adsorption is the dominating state and that the SB surface has certain heterogeneity. The permeability coefficient of K＋, Ca2＋ and Fe3＋ in SB each has a maximum and the higher the valence, the sooner the maximum appears. Also the higher the valence, the more obvious the effect on SB retardation performance; and the sooner the ion breaks through the barrier wall completely, that is, the wall＇s retardation performance for higher valent ions may decline.

关键词： Metal ions Soil-bentonite Barrier materials Retardation Mechanism

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Distribution of antibiotic resistance genes and their association with bacteria and viruses in decentralized sewage treatment facilities

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Frontiers of Environmental Science & Engineering 2022年第3期16卷 91-104页

作者： Jiaheng zhao Bing Li Pin lv Jiahui Hou yong Qiu Xia Huang School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China

The distribution of antibiotic resistance genes(ARGs)has been intensively studied in large-scale wastewater treatment plants and livestock sources.However,small-scale decentralized sewage treatment facilities must also be explored due to their possible direct exposure to residents.In this study,six wastewater treatment facilities in developed rural areas in eastern China were investigated to understand their risks of spreading ARGs.Using metagenomics and network analysis tools,ARGs and bacterial and viral communities were identified in the influent(INF)and effluent(EFF)samples.The dominant ARGs belonged to the bacitracin class,which are different from most of municipal wastewater treatment plants(WWTPs).The dominant hosts of ARGs are Acidovorax in bacterial communities and Prymnesiovirus in viral communities.Furthermore,a positive relationship was found between ARGs and phages.The ARGs significantly correlated with phages were all hosted by specific genera of bacteria,indicating that phages had contributed to the ARG’s proliferation in sewage treatment facilities.Paying significant concern on the possible enhanced risks caused by bacteria,viruses and their related ARGs in decentralized sewage treatment facilities is necessary.

关键词： Decentralized sewage treatment facilities Antibiotic resistance genes Virus Metagenomics Network analysis

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Cardiomyocyte-targeted anti-inflammatory nanotherapeutics against myocardial ischemia reperfusion (IR) injury

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Nano Research 2022年第10期15卷 9125-9134页

作者： Min Lan Mengying Hou Jing Yan Qiurong Deng Ziyin zhao Shixian lv Juanjuan Dang Mengyuan Yin yong Ji Lichen Yin Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Department of Cardiothoracic Surgery Wuxi People’s Hospital Affiliated to Nanjing Medical UniversityWuxi 214023China

Myocardial ischemia reperfusion(IR)injury is closely related to the overwhelming inflammation in the myocardium.Herein,cardiomyocyte-targeted nanotherapeutics were developed for the reactive oxygen species(ROS)-ultrasensitive co-delivery of dexamethasone(Dex)and RAGE small interfering RNA(siRAGE)to attenuate myocardial inflammation.PPTP,a ROSdegradable polycation based on PGE2-modified,PEGylated,ditellurium-crosslinked polyethylenimine(PEI)was developed to surface-decorate the Dex-encapsulated mesoporous silica nanoparticles(MSNs),which simultaneously condensed siRAGE and gated the MSNs to prevent the Dex pre-leakage.Upon intravenous injection to IR-injured rats,the nanotherapeutics could be efficiently transported into the inflamed cardiomyocytes via PGE2-assisted recognition of over-expressed E-series of prostaglandin(EP)receptors on the cell membranes.Intracellularly,the over-produced ROS degraded PPTP into small segments,promoting the release of siRAGE and Dex to mediate effective RAGE silencing(72%)and cooperative antiinflammatory effect.As a consequence,the nanotherapeutics notably suppressed the myocardial fibrosis and apoptosis,ultimately recovering the systolic function.Therefore,the current nanotherapeutics represent an effective example for the codelivery and on-demand release of nucleic acid and chemodrug payloads,and might find promising utilities toward the synergistic management of myocardial inflammation.

关键词： small interfering RNA(siRNA)delivery reactive oxygen species(ROS)responsiveness ditellurium-crosslinked polyethylenimine(PEI) myocardial ischemia reperfusion injury anti-inflammation

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Engineering morphologies of cobalt oxide/phosphate-carbon nanohybrids for high-efficiency electrochemical water oxidation and reduction

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Journal of Energy Chemistry 2021年第1期30卷 139-146,I0005页

作者： Shan-Shan Xu Xian-Wei lv Yan-Mei zhao Tie-Zhen Ren Zhong-yong Yuan Hebei Provincial Key Laboratory of Green Chemical Technology&High Efficient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin 300350China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021NingxiaChina

Active non-noble metal catalysts plays a decisive role for water electrolysis,however,the rational design and development of cost-efficient electrocatalysts with Pt/IrO2-like activity is still a challenging task.Herein,a facile one-step electrodeposition route in deep eutectic solvents(DESs) is developed for morphology-controllable synthesis of cobalt oxide/phosphate-carbon nano hybrids on nickel foam(CoPO@C/NF).A series of CoPO@C/NF nanostructures including cubes,octahedrons,microspheres and nanoflowers are synthesized,which show promising electrocatalytic properties toward oxygen and hydrogen evolution reactions(OER/HER).Such surface self-organized microstructure with accessible active sites make a significant contribution to the enhanced electrochemical activity,and hybridizing cobalt oxide with cobalt pyrophosphates and carbon can result in enhanced OER performance through synergistic catalysis.Among all nanostructures,the obtained microspherical CoPO@C/NF-3 catalyst exhibits excellent catalytic activities for OER and HER in 1.0 M KOH,affording an anodic current density of 10 mA cm^(-2) at overpotentials of 293 mV for OER and 93 mV for HER,with good long-time stability.This work offers a practical route for engineering the high-performance electrocatalysts towards efficient energy conversion and storage devices.

关键词： Cobalt-based electrocatalysts Oxygen evolution reaction Hydrogen evolution reaction Deep eutectic solvents Electrodeposition

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Geochemistry,petrogenesis and tectonic significance of the late Triassic A-type granite in Fujian,South China

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Acta Geochimica 2017年第2期36卷 166-180页

作者： Dawei Cai Jingyu zhao yong Tang Hui Zhang Yunlong Liu Zhenghang lv Key Laboratory for High Temperature and High Pressure Study of the Earth's Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China University of Chinese Academy of Sciences Beijing 100049 China

The late Permian–Triassic granites in southeastern China have important tectonic significance for the evolution of South China. Here, we present the detailed geochronological, geochemical and petrological analyses for the Jinlongyan(JLY) granite in northwest Fujian Province, southeast China. LA–ICP–MS zircon U–Pb dating yielded a weighted average ^(206)Pb/^(238)U age of 224.1 ±3.3 Ma. The granite is mainly comprised of K-feldspar,plagioclase, quartz, biotite and minor amphibole. It is characterized by enrichments in Rb, Th, REEs(total REE = 295.1–694.3 ppm), and HFSEs(e.g., Zr = 289–520 ppm, Hf = 9.3–15.0 ppm, Y = 36.2–68.2 ppm) but depletions in Ba, Sr, Eu and Ti. The granite is metaluminous to weakly peraluminous and show a clear A-type granite geochemical signature with high SiO_2(70.89 wt%–75.76 wt%), total alkalis(Na_2O + K_2O = 7.51 wt%–8.72 wt%), Ga/Al ratios(10000 Ga/Al = 2.72–3.43). Insitu zircon Hf isotope analysis shows their eHf(t) values ranging from-7.2 to-3.2, with Mesoproterozoic T2DM ages(1308–1525 Ma). Whole-rock Nd isotope data show their eNd(t) values in the range of-9.5 to-9.1 and yield paleoproterozoic TDMages(1606–1985 Ma). These characteristics indicate that the JLY A-type granite magma was formed by the partial melting of Meso-Paleoproterozoic crust rocks in the Cathaysia Block. Our study of the JLY A-type granite, together with other Triassic A-type granitesin South China, defines an extensional environment in the late Triassic which probably was caused by the collision of the South China Block with Indochina Block.

关键词：中国南方地区 A型花岗岩构造意义晚三叠世福建省地球化学特征中国东南部家用净水器

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Effect of groundwater depth on riparian plant diversity along riverside-desert gradients in the Tarim River

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Journal of Plant Ecology 2019年第3期12卷 564-573页

作者： yong Zeng Chengyi zhao Jun Li Yan Li Guanghui lv Tong Liu State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of Sciences818 South Beijing RoadUrumqi 830011China College of Resources and Environment Sciences Xinjiang University14 Shengli RoadUrumqi 830046China University of Chinese Academy of Sciences 55 East Zhongguancun East RoadBeijing 100049China Land Science Research Center Nanjing University of Information Science&Technology219 Ningliu RoadNanjing 210044China College of Life Sciences Shihezi University4 North RoadShihezi 832003XinjiangChina

Aims Riparian plant diversity is sensitive to changes in groundwater in arid regions.However,little is known about how plant diversity responds to changes in environment along riverside-desert gradi-ents in riparian ecosystem.Our objectives were to(i)identify ri-parian plant diversity along riverside-desert gradients in Tarim desert riparian forests,(ii)analyze the impact of environment variables on plant diversity,(iii)determine the optimum groundwater depth for different plant life-forms.Methods Six transects 90 quadrats(with each size 100 m×100 m)distributed vertically to river bed along riverside-desert gradients~30 km in length were surveyed.At each quadrat,the morphological features of riparian plant communities were measured,and the groundwater depth,soil water,soil salinity,soil nutrient were also monitored at same sites.Important Finding Three distinct vegetation communities were identified based on cover and richness in the tree,shrub and herb layers:the riparian zone,the transitional zone and the desert margin zone.Twelve spe-cies were indicators of the three vegetation communities.Riparian plant diversity was influenced by groundwater depth,distance from river,soil moisture content,soil salinity and soil nutrient by redundancy analysis.In response to groundwater depth,the op-timal groundwater depths for species diversity,evenness and shrub cover were 2.8,2.7 and 3.7 m,respectively.Therefore,maintaining high plant diversity requires managers to ensure stable groundwater depth for different plant life-forms rather than for some of them.

关键词： vegetation community distance from river groundwater depth Tarim River

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