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Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye Da-ming wei Yi-ming Zhu Zhi-Ping Jin Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

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Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li ming-wei Zhang Ji-Wu Xin Lei wei Wen-Yu Zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

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An approximate analytical model for unconventional reservoir considering variable matrix blocks and simultaneous matrix depletion

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Petroleum Science 2024年第1期21卷 352-365页

作者： Kai-Xuan Qiu Jia Li Dong Feng Shi-ming wei Gang Lei Jiangmen Laboratory of Carbon Science and Technology Jiangmen529100GuangdongChina The Hong Kong University of Science and Technology(Guangzhou) Guangzhou511400GuangdongChina China University of Geosciences(Beijing) Beijing100083China China University of Petroleum(Beijing) Beijing102249China China University of Geosciences(Wuhan) Wuhan430074HubeiChina Shenzhen Research Institute China University of GeosciencesShenzhen518063GuangdongChina

In regard to unconventional oil reservoirs,the transient dual-porosity and triple-porosity models have been adopted to describe the fluid flow in the complex fracture *** has been proven to cause inaccurate production evaluations because of the absence of matrix-macrofracture *** addition,most of the existing models are solved analytically based on Laplace transform and numerical ***,an approximate analytical solution is derived directly in real-time space considering variable matrix blocks and simultaneous matrix *** simplify the derivation,the simultaneous matrix depletion is divided into two parts:one part feeding the macrofractures and the other part feeding the ***,a series of partial differential equations(PDEs)describing the transient flow and boundary conditions are constructed and solved analytically by ***,a relationship between oil rate and production time in real-time space is *** new model is verified against classical analytical *** the microfracture system and matrix-macrofracture communication is neglected,the result of the new model agrees with those obtained with the dual-porosity and triple-porosity model,***,the new model also has an excellent agreement with the numerical *** model is then applied to two actual tight oil wells completed in western Canada sedimentary *** identifying the flow regime,the solution suitably matches the field production data,and the model parameters are *** these output parameters,we can accurately forecast the production and even estimate the petrophysical properties.

关键词： Analytical solution Unconventional reservoir Variable matrix Simultaneous flow

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Effect of ginsenoside Rg1 on hematopoietic stem cells in treating aplastic anemia in mice via MAPK pathway

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World Journal of Stem Cells 2024年第5期16卷 591-603页

作者： Jin-Bo Wang ming-wei Du Yan Zheng Internal Medicine of Traditional Chinese Medicine Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Institute of Cardiovascular Disease Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Key Laboratory of Molecular Medical Mycology Second Affiliated Hospital of Naval Medical UniversityShanghai 200003China Shanghai Key Laboratory of Traditional Chinese Clinical Medicine Shanghai 201203China Department of Hepatic The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese MedicineHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Aplastic anemia(AA)presents a significant clinical challenge as a life-threatening condition due to failure to produce essential blood cells,with the current the-rapeutic options being notably *** To assess the therapeutic potential of ginsenoside Rg1 on AA,specifically its protective effects,while elucidating the mechanism at *** We employed a model of myelosuppression induced by cyclophosphamide(CTX)in C57 mice,followed by administration of ginsenoside Rg1 over 13 *** invest-igation included examining the bone marrow,thymus and spleen for pathological changes via hematoxylin-eosin ***,orbital blood of mice was collected for blood routine *** cytometry was employed to identify the impact of ginsenoside Rg1 on cell apoptosis and cycle in the bone marrow of AA ***,the study further evaluated cytokine levels with enzyme-linked immunosorbent assay and analyzed the expression of key proteins in the MAPK signaling pathway via western *** Administration of CTX led to significant damage to the bone marrow’s structural integrity and a reduction in hematopoietic cells,establishing a model of *** Rg1 successfully reversed hematopoietic dysfunction in AA *** comparison to the AA group,ginsenoside Rg1 provided relief by reducing the induction of cell apoptosis and inflammation factors caused by ***,it helped alleviate the blockade in the cell *** with ginsenoside Rg1 significantly alleviated myelosuppression in mice by inhibiting the MAPK signaling *** This study suggested that ginsenoside Rg1 addresses AA by alleviating myelosuppression,primarily through modulating the MAPK signaling pathway,which paves the way for a novel therapeutic strategy in treating AA,highlighting the potential of ginsenoside Rg1 as a beneficial intervention.

关键词： Aplastic anemia Ginsenoside Rg1 Myelosuppression MAPK signaling pathway Bone marrow Hematopoietic stem cells

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A novel method for simulating nuclear explosion with chemical explosion to form an approximate plane wave: Field test and numerical simulation

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2137-2153页

作者： wei ming Xiaojie Yang Yadong Mao Xiang Wang Manchao He Zhigang Tao College of Civil and Architecture Engineering North China University of Science and TechnologyTangshan063210China State Key Laboratory for Tunnel Engineering China University of Mining and Technology-BeijingBeijing100083China School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing100083China

A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection *** the increase in nuclear explosion power,underground protection engineering enabled by explosion-proof impact theory and technology ushered in a new *** paper proposes to simulate nuclear explosion tests with on-site chemical explosion tests in the form of multi-hole ***,the mechanism of using multi-hole simultaneous blasting to simulate a nuclear explosion to generate approximate plane waves was *** plane pressure curve at the vault of the underground protective tunnel under the action of the multi-hole simultaneous blasting was then obtained using the impact test in the rock mass at the *** to the peak pressure at the vault plane,it was divided into three regions:the stress superposition region,the superposition region after surface reflection,and the approximate plane stress wave zone.A numerical simulation approach was developed using PFC and FLAC to study the peak particle velocity in the surrounding rock of the underground protective cave under the action of multi-hole *** time-history curves of pressure and peak pressure partition obtained by the on-site multi-hole simultaneous blasting test and numerical simulation were compared and analyzed,to verify the correctness and rationality of the formation of an approximate plane wave in the simulated nuclear *** comparison and analysis also provided a theoretical foundation and some research ideas for the ensuing study on the impact of a nuclear explosion.

关键词： Approximate plane wave Multi-hole simultaneous blasting Chemical explosion Nuclear explosion Pressure sensor inclusion

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Challenges and opportunities for battery health estimation:Bridging laboratory research and real-world applications

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Journal of Energy Chemistry 2024年第2期89卷 434-436,I0011页

作者： Te Han Jinpeng Tian C.Y.Chung Yi-ming wei Center for Energy and Environmental Policy Research Beijing Institute of TechnologyBeijing 100081China School of Management and Economics Beijing Institute of TechnologyBeijing 100081China Department of Electrical and Electronic Engineering and Research Centre for Grid Modernization The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina

Addressing climate change demands a significant shift away from fossil fuels,with sectors like electricity and transportation relying heavily on renewable *** to this transition are energy storage systems,notably lithium-ion *** time,these batteries degrade,affecting their efficiency and posing safety *** and predicting battery aging is essential,especially estimating its state of health(SOH).Various SOH estimation methods exist,from traditional model-based approaches to machine learning approaches.

关键词： Energy storage systems State of health Multi-source data Scientific AI Data-sharing mechanism

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Effect of temperature and reaction path interaction on fluidization reduction kinetics of iron ore powder

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Journal of Iron and Steel Research International 2024年第8期31卷 1840-1849页

作者： Guo-min Zhu ming-wei Hu An-nan Dou Jin-yu Huang Jing Ding Qi-yan Xu School of Metallurgical Engineering Anhui University of TechnologyMa'anshan 243002AnhuiChina

Due to the instability of FeO at temperatures below 843 K,the fuidization reduction pathway of iron ore powder changes with the reduction ***,the effect of temperature and reaction pathway interaction on the kinetics of fuidization reduction of iron ore powder under low-temperature conditions ranging from 783 to 903 K was investigated to describe the fluidization reduction rate of iron ore powder from three aspects:microstructure change,reaction limiting link,and apparent activation energy of the reaction,exploring their internal *** experimental results revealed that in a temperature range of 783-813 K,the formation of a dense iron layer hindered the internal diffusion of reducing gas,resulting in relatively high gas diffusion *** addition,due to the differences in limiting links and reaction pathways in the intermediate stage of reduction,the apparent activation energy of the reaction *** apparent activation energy of the reaction ranged from 23.36 to 89.13 kJ/mol at temperature ranging from 783 to 813 K,while it ranged from 14.30 to 68.34 kJ/mol at temperature ranging from 873 to 903 K.

关键词： Reaction limiting link Gas internal diffusion Interface reaction Apparent activation energy Iron ore powder Reaction pathway Fluidization reduction

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Supramolecular polymer-based gel fracturing fluid with a double network applied in ultra-deep hydraulic fracturing

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Petroleum Science 2024年第3期21卷 1875-1888页

作者： Yong-Ping Huang Yong Hu Chang-Long Liu Yi-Ning Wu Chen-wei Zou Li-Yuan Zhang ming-wei Zhao Cai-Li Dai School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Shandong Key Laboratory of Oilfield Chemistry China University of Petroleum(East China)Qingdao 266580ShandongPR China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206PR China CNOOC China Co Ltd Tianjin BranchTianjin300459PR China

A gel based on polyacrylamide,exhibiting delayed crosslinking characteristics,emerges as the preferred solution for mitigating degradation under conditions of high temperature and extended shear in ultralong *** viscosity/viscoelasticity of the fracturing fluid was required to maintain excellent proppant suspension properties before *** into account both the cost and the potential damage to reservoirs,polymers with lower concentrations and molecular weights are generally *** this work,the supramolecular action was integrated into the polymer,resulting in significant increases in the viscosity and viscoelasticity of the synthesized supramolecular polymer *** double network gel,which is formed by the combination of the supramolecular polymer system and a small quantity of Zr-crosslinker,effectively resists temperature while minimizing permeability damage to the *** results indicate that the supramolecular polymer system with a molecular weight of(268—380)×10^(4)g/mol can achieve the same viscosity and viscoelasticity at 0.4 wt%due to the supramolecular interaction between polymers,compared to the 0.6 wt%traditional polymer(hydrolyzed polyacrylamide,molecular weight of 1078×10^(4)g/mol).The supramolecular polymer system possessed excellent proppant suspension properties with a 0.55 cm/min sedimentation rate at 0.4 wt%,whereas the0.6 wt%traditional polymer had a rate of 0.57 cm/*** comparison to the traditional gel with a Zrcrosslinker concentration of 0.6 wt%and an elastic modulus of 7.77 Pa,the double network gel with a higher elastic modulus(9.00 Pa)could be formed only at 0.1 wt%Zr-crosslinker,which greatly reduced the amount of residue of the fluid after *** viscosity of the double network gel was66 m Pa s after 2 h shearing,whereas the traditional gel only reached 27 m Pa s.

关键词： Ultra-deep reservoir Gel fracturing fluid Double network Supramolecular polymer system Proppant suspension property

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Age-specific distribution of oculometric parameters and myopia in children aged 8-12y

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1887-1897页

作者： Tao Tang Si-Tong Chen Heng Zhao Kai Wang ming-wei Zhao Department of Ophthalmology&Clinical Centre of Optometry Peking University People’s HospitalBeijing 100044China Institute of Medical Technology Peking University Health Science CenterBeijing 100083China College of Optometry Peking University Health Science CenterBeijing 100083China Eye Disease and Optometry Institute Peking University People’s HospitalBeijing 100044China Beijing Key Laboratory of the Diagnosis and Therapy of Retinal and Choroid Diseases Beijing 100044China National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhou 325027Zhejiang ProvinceChina

AIM:To describe the distribution of ocular biometrics and to evaluate its associations with refractive error and to assess the contribution from ocular parameters to refractive error among Chinese myopic ***:This cross-sectional study evaluated subjects aged ***,ocular biometry,and cycloplegic autorefraction were performed on each *** equivalent refraction(SER)and ocular biometrics were assessed as a function of age and *** Pearson correlation analysis between SER and ocular biometrics was carried *** linear regression was performed to analyze the association between SER and ocular ***:A total of 689 out of 735 participants(321 boys,48.1%)were analyzed,with a mean SER of-2.98±1.47 diopter(D).Axial length(AL),anterior chamber depth(ACD),corneal radius of curvature(CR),horizontal visible iris diameter(HVID),central corneal thickness(CCT)and lens power(LP)showed normal *** AL,AL/CR ratio,ACD and CR increased from 8 to 12y of age,while SER and LP decreased,HVID and CCT remained *** was no difference in *** decreased by 0.929 D for every 1 mm increase in AL and decreased by 1.144 D for every 0.1 increase in AL/CR *** Pearson correlation coefficient between SER and AL was-0.538(P<0.01)and-0.747(P<0.01)between SER and AL/CR *** the SER variance,AL explained 29.0%,AL/CR ratio explained 55.7%,while AL,CR,ACD and LP explained 99.3%after adjusting for age and ***:The AL,CR,ACD and LP are the most important determinants of myopic refractive error during myopia progression.

关键词： myopia ocular biometry refractive error population-based study

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Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： Zhi-Gang Chen Gao-Qin Liu wei-ming Liu Pei-Rong Lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both P<0.05).Vialinin A also inhibited highglucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(P<0.05).CONCLUSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability

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