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Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research(International) 2024年第3期31卷 752-766页

作者： Yan Qi Xin zhang jun Li Dong-liang Zhao shi-hai Guo Yang-huan zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly Ni.The enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better performance.The experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction melting.The phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron microscopy.The cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni phase.The isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric analyzer.The activation energy may be calculated using the Arrhenius and Kissinger equations.The experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first cycle.The initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni substitution.It can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

Microstructural characterization and mechanical properties of(TiC+TiB)/TA15 composites prepared by an in-situ synthesis method

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China Foundry 2024年第2期21卷 168-174页

作者： Zhi-yong zhang Jiao-jiao Cheng Jia-qi Xie shi-bing Liu Kun shi jun Zhao Shenyang Research Institute of Foundry Co. Ltd.CAMShenyang 110022China National Key Laboratory of Advanced Casting Technologies Shenyang 110022China

Titanium matrix composites reinforced with ceramic particles are considered a promising engineering material due to their combination of high specific strength,low density,and high modulus.In this study,the TA15-based composites reinforced with a volume fraction of 10% to 25%(TiB+TiC)were prepared using powder metallurgy and casting technique.Microstructural characterization and phase constitution were examined using optical microscopy(OM),scanning electron microscopy(SEM),and X-ray diffraction(XRD).In addition,the microhardness,room temperature(RT)and high temperature(HT)tensile properties of the composites were evaluated.Results revealed that the reinforcements are distributed uniformly even in the composites with a high volume of TiB and TiC.However,as the volume fraction exceeds 15%,TiB and TiC particles become coarsening and exhibit rod-like and dendritic-like morphology.Microhardness increases gradually from 321.2 HV for the base alloy to a maximum of 473.3 HV as the reinforcement increases to 25vol.%.Tensile test results indicate that a reinforcement volume fraction above 20% is beneficial for enhancing tensile strength and yield strength at high temperatures,but it has an adverse effect on room temperature elongation.Conversely,if the reinforcement volume fraction is below 20%,it can improve high-temperature elongation when the temperature exceeds 600℃.

关键词： titanium matrix composites microstucture microhardness tensile properties in-situ synthesis

Micro-nanoarchitectonic of aluminum-hydrogel propellant with static stability and dynamic rheology

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Frontiers of Chemical Science and Engineering 2024年第4期18卷 87-96页

作者： Huiyan Guo Huaiyu Li Hongzhi zhang Lun Pan Chengxiang shi Kang Xue Xiangwen zhang Ji-jun Zou Key Laboratory for Advanced Fuel and Propellant of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

The aluminum-water system is a promising propellant due to high energy and low signal characteristics,and the gel form is easier to store and utilize.In this work,hydrogels of water and aluminum particles were prepared using the low-molecular-weight gellant agarose.The various physical properties of gel systems,including the water loss rate,phase transition temperature,and centrifugal stability at different gellant and aluminum contents,were examined.Rheological properties were assessed through shear thinning tests,thixotropy tests,strain sweep analysis,and frequency sweep experiments.The microstructure of the gel was obtained through scanning electron microscopy images.The results show that the aluminum-hydrogel network structure is composed of micron-scale aluminum and agarose nanosheets,and the unique micro-nanostructure endows the gel with excellent mechanical strength and thermal stability,which improve with increasing gellant and aluminum contents.Notably,the gel with 2% agarose and 20% aluminum had the best performance;the storage modulus reached 90647 Pa,which was within the linear viscoelastic region,and the maximum withstand pressure was 111.2 kPa,which was 118.8% greater than that of the pure hydrogel.Additionally,the gel demonstrates remarkable shear thinning behavior and can undergo gel-sol transformation upon shearing or heating to exceeding 114℃.

关键词： aluminum-water propellant gelled propellant rheological property mechanical strength

Incremental Data Stream Classification with Adaptive Multi-Task Multi-View Learning

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Big Data Mining and Analytics 2024年第1期7卷 87-106页

作者： jun Wang Maiwang shi Xiao zhang Yan Li Yunsheng Yuan Chengei Yang Dongxiao Yu School of Computer Science and Technology Shandong UniversityQingdao 266237China School of Software Shandong UniversityJinan 250101China

With the enhancement of data collection capabilities,massive streaming data have been accumulated in numerous application scenarios.Specifically,the issue of classifying data streams based on mobile sensors can be formalized as a multi-task multi-view learning problem with a specific task comprising multiple views with shared features collected from multiple sensors.Existing incremental learning methods are often single-task single-view,which cannot learn shared representations between relevant tasks and views.An adaptive multi-task multi-view incremental learning framework for data stream classification called MTMVIS is proposed to address the above challenges,utilizing the idea of multi-task multi-view learning.Specifically,the attention mechanism is first used to align different sensor data of different views.In addition,MTMVIS uses adaptive Fisher regularization from the perspective of multi-task multi-view learning to overcome catastrophic forgetting in incremental learning.Results reveal that the proposed framework outperforms state-of-the-art methods based on the experiments on two different datasets with other baselines.

关键词： data stream classification mobile sensors multi-task multi-view learning incremental learning

FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei Jiang Ping Cao Yi-Ming Wu Xian-Ke Liu Zhu-jun Fang Zhi-Yong zhang Bin shi jun Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas detector.To address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber principle.This method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined RAM.The performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data transmission.The experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 mm.The beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction method.The online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-Dong Liu Xiao Tang jun-An Feng Chao-Yue zhang Hao Liu Chuan shi Xiao-Xian Zhao Jian-jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application prospects.However,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of LSBs.In response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of LSBs.Recently,vacancy engineering has gained the attention of researchers due to its unique electronic structure.This review aims to analyze the application of vacancy engineering in LSBs.Firstly,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been presented.Subsequently,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,etc.The latest applications of vacancy engineering in LSBs are also summarized in this review.Finally,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

Two-dimensional precise figuring of 500 mm-long X-ray mirror using one-dimensional ion beam system

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Advances in Manufacturing 2024年第1期12卷 177-184页

作者： Qiu-shi Huang Han-Dan Huang Qiao-Yu Wu jun Yu Zhong zhang Zhan-Shan Wang MOE Key Laboratory of Advanced Micro-Structured Materials Institute of Precision Optical Engineering(IPOE)School of Physics Science and EngineeringTongji UniversityShanghai200092People’s Republic of China Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications Tongji UniversityShanghai200092People’s Republic of China Shanghai Frontiers Science Center of Digital Optics Tongji UniversityShanghai200092People’s Republic of China

In this study,a new method was developed to realize two-dimensional(2D)figure correction of grazing-incidence X-ray mirrors using a one-dimensional(1D)ion-beam figuring system.A mask of holes was specifically designed to generate removal functions at different widths and extend the figuring capability over a wide area.Accordingly,a long mirror could be manufactured.Using this method,the surface height root-mean-square(RMS)error of the center area of 484 mm×16 mm was reduced from 11.49 nm to 2.01 nm,and the 1D meridional RMS error reached 1.0 nm.The proposed method exhibits high precision and cost effectiveness for production of long X-ray mirrors.

关键词： Long-size mirrors Ion beam figuring Two-dimensional figure correction Mask

Immunomodulation of adipose-derived mesenchymal stem cells on peripheral blood mononuclear cells in colorectal cancer patients with COVID-19

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2113-2122页

作者： jun-Feng Wang Xiao-Xia Yang Jian zhang Yan Zheng Fu-Qing zhang Xiao-Feng shi Yu-Liang Wang Department of Colorectal Oncology Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060China Department of Neurology Tianjin First Center HospitalTianjin 300192China Prosthodontics Studio Tianjin Stomatological HospitalTianjin 300041China Department of Clinical Laboratory Medicine Tianjin Institute of UrologyThe Second Hospital of Tianjin Medical UniversityTianjin 300211China Department of Emergency Tianjin First Central HospitalTianjin 300192China

BACKGROUND Accumulating evidence has shown that adipose tissue-derived mesenchymal stem cells(ADSCs)are an effective therapeutic approach for managing coronavirus disease 2019(COVID-19);however,further elucidation is required to determine their underlying immunomodulatory effect on the mRNA expression of T helper cell-related transcription factors(TFs)and cytokine release in peripheral blood mononuclear cells(PBMCs).AIM To investigate the impact of ADSCs on the mRNA expression of TFs and cytokine release in PBMCs from colorectal cancer(CRC)patients with severe COVID-19(CRC^(+)patients).METHODS PBMCs from CRC^(+)patients(PBMCs-C+)and age-matched CRC patients(PBMCs-C)were stimulated and cultured in the presence/absence of ADSCs.The mRNA levels of T-box TF TBX21(T-bet),GATA binding protein 3(GATA-3),RAR-related orphan receptor C(RORC),and forkhead box P3(FoxP3)in the PBMCs were determined by reverse transcriptase-polymerase chain reaction.Culture supernatants were evaluated for levels of interferon gamma(IFN-γ),interleukin 4(IL-4),IL-17A,and transforming growth factor beta 1(TGF-β1)using an enzyme-linked immunosorbent assay.RESULTS Compared with PBMCs-C,PBMCs-C+exhibited higher mRNA levels of T-bet and RORC,and increased levels of IFN-γ and IL-17A.Additionally,a significant decrease in FoxP3 mRNA and TGF-β1,as well as an increase in Tbet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios were observed in PBMCs-C+.Furthermore,ADSCs significantly induced a functional regulatory T cell(Treg)subset,as evidenced by an increase in FoxP3 mRNA and TGF-β1 release levels.This was accompanied by a significant decrease in the mRNA levels of T-bet and RORC,release of IFN-γ and IL-17A,and T-bet/GATA-3,RORC/FoxP3,IFN-γ/IL-4,and IL-17A/TGF-β1 ratios,compared with the PBMCs-C+alone.CONCLUSION The present in vitro studies showed that ADSCs contributed to the immunosuppressive effects on PBMCs-C+,favoring Treg responses.Thus,ADSC-based cell therapy could be a beneficial approach for patients with severe COVID-19 who fail to respond

关键词： Colorectal cancer COVID-19 Adipose-derived mesenchymal stem cells T helper cell Immunomodulation

Circadian disturbance induces erectile dysfunction by impairing endothelial function

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Asian Journal of Andrology 2024年第2期26卷 205-211页

作者： Tao Li Yi-Ting Jiang Xin-Zhu Qi Peng Chen jun-Hao zhang Fu Luo jun Qiao Jiang Gu Guang-shi Du Qiang Wang Department of Urology Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Urology Guizhou Provincial People's HospitalGuiyang 550002China Department of Otorhinolaryngology Affiliated Hospital of Guizhou Medical UniversityGuiyang 550004China Guizhou Institute for Food and Drug Control Guiyang 550004China Department of Reproductive Center Guizhou Provincial People's HospitalGuiyang 550002China Translational Medicine Research Center of Guizhou Medical University Guiyang 550025China

In order to explore the impact of circadian disturbance on erectile function,we randomly divided 24 adult male rats into groups of control(light on at 8:00 a.***.and off at 8:00 p.m.),dark/dark(DD;constant dark),light/light(LL;constant light),and shift dark/light(DL;light off at 8:00 a.***.and on at 8:0o p.m.).Four weeks later,erectile function was measured and corpora cavernosa were harvested for analysis.The maximum intracavernous pressure(mlcP)and mCP/mean arterial pressure(MAP)ratio in the DD,LL,and DL groups were significantly lower than that in the control group.The LL and DL groups showed significantly attenuated endothelial nitric oxide synthase(eNOS),while DD,LL,and DL showed reduced neuronal nitric oxide synthase(nNOS)at both mRNA and protein levels.The production of nitric oxide(NO)and cyclic guanosinemonophosphate(cGMP)was inhibited by altered light/dark cycles to varying degrees.Circadian disturbance impaired endothelial function and contributed to erectile dysfunction.For the core circadian elements,mRNA expression of circadian locomotor output cycles kaput(Clock)and brain/muscle aryl-hydrocarbon receptor nuclear translocator-like protein 1(Bmal1)was elevated in the DL group,but their protein expression was not significantly changed.DD,LL,and DL increased period 1(Per1)and Per3 levels,while LL and DL increased PER1 levels.No significant difference was found for Per2levels,and PER2 and PER3 concentrations were not significantly changed.Moreover,LL and DL significantly increased cryptochrome-1(CRY1)and CRY2 at both mRNA and protein levels.The altered light/dark rat model showed that circadian disturbance contributed to erectile dysfunction probably by impairing endothelial function.Meanwhile,the core circadian elements were detected in the corpora cavernosa,but these were disrupted.However,which circadian element regulates erectile function and how it works need further analysis.

关键词： circadian disturbance endothelial function erectile function light/dark cycle NO/cGMP