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A synthesis of the Cretaceous wildfire record related to atmospheric oxygen levels?

Journal of Palaeogeography 2024年第1期13卷 149-164页

作者： Da-Wei Lü Wen-Xu Du Zhi-Hui Zhang Yuan Gao Tian-Tian wang Jin-cheng Xu ao-Cong Zhang cheng-Shan wang Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals College of Earth Sciences and EngineeringShandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina School of Earth Sciences and Resources China University of GeosciencesBejing 100083China Institute of Earth Sciences China University of Geosciences(Bejing)Beijing 100083China

The Cretaceous was a significant greenhouse period in Earth's history with higher atmospheric CO_(2) levels and temperatures than today. Although evidence of combustion has been widely described from the Cretaceous deposits, our understanding of the spatiotemporal diversification pattern and process of the Cretaceous wildfires is still limited. In this study, we comprehensively synthesize a total of 271 published Cretaceous wildfire occurrences based on the by-products of burning, including fossil charcoal, pyrogenic inertinite(fossil charcoal in coal), and pyrogenic polycyclic aromatic hydrocarbons(PAHs). Spatially, the dataset shows a distinctive distribution of reported wildfire evidence characterized by high concentration in the middle latitudinal areas of the Northern Hemisphere(30°N-60°N) over the Cretaceous. Temporally, an overall increasing trend of the reported wildfire data from the Early Cretaceous to the Late Cretaceous is coincident with higher atmospheric O_(2) levels. However, the spatial and temporal patterns may result from many types of factors, such as taphonomy, preservation, and researcher biases, instead of a real picture of the Cretaceous wildfire evolution. To better understand the spatiotemporal diversification of the Cretaceous wildfire, more investigations on the record of wildfire occurrences during this period would be necessary in the future.

关键词： Wildfire Cretaceous Atmospheric oxygen Taphonomy Charcoal

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Effect of MgO-Cr_(2)O_(3) and Mg0-MgAl_(2)0_(4)-based refractories on refractory-steel interface reaction and cleanliness of pipeline steel

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Journal of Iron and Steel Research(International) 2024年第4期31卷 849-860页

作者： Guang-mei Yang cheng Yuan Chang Liu Qiang wang Guang-qiang Li Yong-shun Zou ao Huang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The interaction of MgO-MgAl_(2)O_(4)-based and MgO-Cr_(2)O_(3)-based refractories with X70 molten steel was studied by immersion experiments at 1560℃.The effects of immersion time(30 and 60 min)on the contents of total oxygen(TO),Al,Nb,Si,Mn,and Cr as well as the composition,number density,and size distribution of inclusions in the molten steel were investigated.The influence of the penetration and erosion degree of the molten steel to the refractory on the steel-refractory interface layer was analyzed.The results show that,at 1560℃,the MgO-MgAl_(2)O_(4)-based refractory can better control the contents of TO and the composition of molten steel compared with the MgO-Cr_(2)O_(3)-based refractory.The TO content is only 16×10^(-4) wt.%in the molten steel after reacted with the Mg0-MgAl_(2)O_(4)-based refractory at the end point of refining,4 accounting for 11.5%of that reacted with the MgO-Cr_(2)O_(3)-based refractory(139×10^(-4) wt.%).The number density of inclusions is only 14 mm^(-2),and the average size ofinclusions is only 1.31μm,with thelargest proportion of inclusions in 1-2μm(70%).The Al_(2)O_(3)-MnS-Cao complex inclusions in the original steel changed to complex inclusions dominated by Cr-Nb-Mn-S-O and MgO.Al_(2)O_(3),corresponding to the MgO-Cr_(2)O_(3)-based and MgO-MgAl_(2)O_(4)-based refractories,respectively.The MgO.Al_(2)O_(3) layer was formed at the reaction interface between MgO-MgAl_(2)O_(4)-based refractory and molten steel,which is helpful to restrict the erosion of refractories and the pollution of molten steel.The damage mechanism of the MgO-Cr_(2)O_(3)-based refractory is mainly permeation and chemical reaction,while the damage of the MgO-MgAl_(2)O_(4)-based refractory is mainlyscouring erosion.

关键词： MgO-Cr_(2)O_(3)-based refractory MgO-MgAl O_(4)-based refractory Nonmetallic inclusion Erosion interface layer Steel penetration

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Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng wang Xiaoqi wang Shuiyuan cheng Jiaxian Zhu Xinyu Zhang Long cheng Kai wang Key Laboratory of Beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in China.We estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research results.Then,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was analyzed.Moreover,priority control routes for VOC emission sources were proposed for different periods.Anthropogenic VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main contributors.Industrial protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and SOAFP.Priority in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in China.In addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

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Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443

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Chinese Journal of Integrative Medicine 2024年第3期30卷 213-221页

作者： ZHANG Yue XIao Yan-wei MA Jing-xin wang ao-xue Department of Dermatology the Second Hospital of Dalian Medical UniversityDalianLiaoning Province116021China Department of Cell Biology Dalian Medical UniversityDalianLiaoning Province116044China

Objective:To investigate the effect and possible mechanism of hydroxysafflor yellow A(HSYA) on human immortalized keratinocyte cell proliferation and migration.Methods:HaCaT cells were treated with HSYA.Cell proliferation was detected by the cell counting kit-8 assay,and cell migration was measured using wound healing assay and Transwell migration assay.The mRNA and protein expression levels of heparin-binding epidermal growth factor(EGF)-like growth factor(HBEGF),EGF receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),and hypoxia-inducible factor-1α(HIF-1α) were detected by quantitative real-time polymerase chain reaction(qRT-PCR) and Western blot,respectively.Circ_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with HSYA.The expression of circ_0084443 was detected by qRT-PCR.Results:HSYA(800 μmol/L) significantly promoted HaCaT cell proliferation and migration(P0.05).Conclusion:HSYA played an accelerative role in HaCaT cell proliferation and migration,which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways,and had a particular inhibitory effect on the keratinocyte negative regulator circ_0084443.

关键词： hydroxysafflor yellow A circ_0084443 heparin-binding epidermal growth factor-like growth factor/epidermal growth factor receptor phosphatidylinositol 3-kinase/protein kinase B

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Selenium-oxidizing Agrobacterium sp.T3F4 decreases arsenic uptake by Brassica rapa L.under a native polluted soil

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Journal of Environmental Sciences 2024年第4期138卷 506-515页

作者： Lijin An Chunzhi Zhou Lipeng Zhao ao Wei Yiting wang Huimin Cui Shixue Zheng State Key Laboratory of Agricultural Microbiology College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China

Toxic arsenic(As)and trace element selenium(Se)are transformed by microorganisms but their complex interactions in soil-plant systems have not been fully understood.An Asand Se-oxidizing bacterium,Agrobacterium sp.T3F4,was applied to a native seleniferous As-polluted soil to investigate As/Se uptake by the vegetable Brassica rapa L.and As-Se interaction as mediated by strain T3F4.The Se content in the aboveground plants was significantly enhanced by 34.1%,but the As content was significantly decreased by 20.5% in the T3F4-inoculated pot culture compared to the control(P<0.05).Similar result was shown in treatment with additional 5 mg/kg of Se(IV)in soil.In addition,the As contents in roots were significantly decreased by more than 35% under T3F4 or Se(IV)treatments(P<0.05).Analysis of As-Se-bacterium interaction in a soil simulation experiment showed that the bioavailability of Se significantly increased and As was immobilized with the addition of the T3F4strain(P<0.05).Furthermore,an As/Se co-exposure hydroponic experiment demonstrated that As uptake and accumulation in plants was reduced by increasing Se(IV)concentrations.The 50% growth inhibition concentration(IC50)values for As in plants were increased about one-fold and two-fold under co-exposure with 5 and 10μmol/L Se(IV),respectively.In conclusion,strain T3F4 improves Se uptake but decreases As uptake by plants via oxidation of As and Se,resulting in decrease of soil As bioavailability and As/Se competitive absorption by plants.This provides a potential bioremediation strategy for Se biofortification and As immobilization in As-polluted soil.

关键词： Selenium oxidation Selenium biofortification Arsenite-oxidizing bacteria Arsenic immobilization Brassica rapa L

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Europium-bearing organic framework with excellent X-ray scintillating luminescence

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Journal of Rare Earths 2024年第2期42卷 251-255,I0001页

作者： Yugang Zhang Lanhua Chen Xia wang Wei Liu Shu'ao wang State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123China School of Environmental and Materials Engineering Yantai UniversityYantai264005China

Two europium-bearing organic frameworks,termed as EuTPO-1 and EuTPO-2(H_(3)TPO=tris(4-carboxylphenyI)-phosphineoxide),are reported in this work.A series of characterizations of EuTPO-1and EuTPO-2,such as X-ray crystallography and photoluminescence spectroscopy,was performed to expatiate their structure and physicochemical properties.Both of them are constructed by dimers of the europium-oxygen subunit of [Eu_(2)O_(16)] and TPO molecule.Benefiting from high X-ray stopping attenuation and excellent luminescence efficiency,they emit sufficient luminescence when irradiated with Xrays.Meanwhile,they possess stable light outputs when exposed to high humidities and strong radiation dose,outperforming the commercial scintillator CsI:Tl.This result paves the way for developing new scintillator and enriches the compound of europium-bearing organic framework with X-ray scintillating luminescence.

关键词： Metal-organic frameworks Scintillating material Luminescence efficiency Rare earths

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Effect of slow shot speed on externally solidified crystal,porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy

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China Foundry 2024年第1期21卷 11-19页

作者： Wen-ning Liu Wei Zhang Peng-yue wang Yi-xian Liu Xiang-yi Jiao ao-xiang Wan cheng-gang wang Guo-dong Tong Shou-mei Xiong School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Tsinghua UniversityBeijing 100084Beijing China FAW Group Co. Ltd.Changchun 130013China China FAW Foundry Co. Ltd.Changchun 130013China

The effect of slow shot speed on externally solidified crystal(ESC),porosity and tensile property in a newly developed high-pressure die-cast Al-Si alloy was investigated by optical microscopy(OM),scanning electron microscopy(SEM)and laboratory computed tomography(CT).Results showed that the newly developed AlSi9MnMoV alloy exhibited improved mechanical properties when compared to the AlSi10MnMg alloy.The AlSi9MnMoV alloy,which was designed with trace multicomponent additions,displays a notable grain refining effect in comparison to the AlSi10MnMg alloy.Refining elements Ti,Zr,V,Nb,B promote heterogeneous nucleation and reduce the grain size of primaryα-Al.At a lower slow shot speed,the large ESCs are easier to form and gather,developing into the dendrite net and net-shrinkage.With an increase in slow shot speed,the size and number of ESCs and porosities significantly reduce.In addition,the distribution of ESCs is more dispersed and the net-shrinkage disappears.The tensile property is greatly improved by adopting a higher slow shot speed.The ultimate tensile strength is enhanced from 260.31 MPa to 290.31 MPa(increased by 11.52%),and the elongation is enhanced from 3.72%to 6.34%(increased by 70.52%).

关键词： hypoeutectic Al-Si alloy high pressure die casting porosity externally solidified crystal tensile property

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Chelators to assist the high dispersion of Ni_(2)P particles over mesoporous silica nanospheres for hydrogenating reaction

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Petroleum Science 2023年第3期20卷 1895-1902页

作者： Di Hu En-Hua wang ao-cheng wang Ai-Jun Duan State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing102249China

NizP supported catalysts exhibit high catalytic activities in hydrogenation reaction,of which the particle sizes of Ni_(2)P active phases are the key influential factor.This research focus on the effect of chelators on the size of Ni_(2)P particles over wrinkle silica nanoparticles(WSNs)by introducing chelating agents EDTA and NTA during impregnation process.The characterization results show that chelators modified cata-lysts possess smaller size of Ni_(2)P particles than the unmodified Ni_(2)P catalysts.Among all the synthesized catalysts,the EDTA modified Ni_(2)PE(1.5)/WSNs catalyst possesses smallest average particle size of Ni_(2)P,only 2.6 nm.Moreover,the Ni_(2)P catalysts with the assistance of EDTA exhibits better catalytic activity than that of NTA under high reaction temperature,which can be ascribed to the strong bonding between EDTA and Ni.And the EDTA modified Ni_(2)PE(1.5)/WSNs catalyst shows highest hydrogenation ability,almost reaching 100%decalin selectivity.

关键词： Wrinkle silica nanoparticles Chelators Ni_(2)P supported catalysts Naphthalene hydrogenation

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Recent progress in functional modification and crosslinking of bioprosthetic heart valves

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Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： cheng Zheng Li Yang Yunbing wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been recognized as golden standard for the treatment of VHD.Owing to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of VHD.However,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune response.To prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of SVD.In this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

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Towards a blood ecosystem approach to dissect systemic diseases

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Science China(Life Sciences) 2024年第7期67卷 1528-1531页

作者： Hong wang Tao cheng State Key Laboratory of Experimental Hematology Haihe Laboratory of Cell EcosystemNational Clinical Research Center for Blood DiseasesInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300020China Tianjin Institutes of Health Science Tianjin 301600China

Systemic diseases,in contrast to localized ailments,exert widespread effects and can impact the entire body.Examples of systemic diseases encompass autoimmune disorders,infectious diseases,metabolic disorders,and chronic conditions like cancer.These diseases often entail intricate interactions among diverse organs,tissues,and physiological systems,influenced by a myriad of factors.

关键词： diseases organs autoimmune

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