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Porous TiFe_(2) intermetallic compound fabricated via elemental powder reactive synthesis

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 764-772页

作者： Qian zhao Zhenli He Yuehui He Yue Qiu Zhonghe Wang Yao jiang State Key Laboratory of Powder Metallurgy Powder Metallurgy Research InstituteCentral South UniversityChangsha 410083China

Porous intermetallics show potential in the field of filtration and separation as well as in the field of ***,porous Ti Fe2intermetallics were fabricated by the reactive synthesis of elemental *** phase transformation and pore formation of porous TiFe2intermetallics were investigated,and its corrosion behavior and hydrogen evolution reaction(HER)performance in alkali solution were *** TiFe2intermetallics with porosity in the range of 34.4%-56.4%were synthesized by the diffusion reaction of Ti and Fe elements,and the pore formation of porous TiFe2intermetallic compound is the result of a combination of the bridging effect and the Kirkendall *** porous TiFe2samples exhibit better corrosion resistance compared with porous 316L stainless steel,which is related to the formation of uniform nanosheets on the surface that hinder further corrosion,and porous TiFe2electrode shows the overpotential of 220.6 and 295.6 mV at 10 and 100 mA·cm-2,suggesting a good catalytic *** synthesized porous Fe-based intermetallic has a controllable pore structure as well as excellent corrosion resistance,showing its potential in the field of filtration and separation.

关键词： TiFe2 intermetallic compound porous materials reactive synthesis corrosion behavior hydrogen evolution reaction

Synergistic enhancement of Ce-ZnO/g-C_(3)N_(4)photocatalytic performance using N,O-bis-vacancy induction and S-scheme heterojunctions

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Journal of Rare Earths 2024年第5期42卷 817-826,I0001页

作者： Guyu Zhang Yuan Zhang Xinlei zhao Yujiang Jiao Yumin Yan Jianhui jiang Engineering Laboratory of Chemical Resources Utilization in South Xinjiang of Xinjiang Production and Construction Corps College of Chemistry a Chemical EngineeringTarimUniversityAlar843300China

The photocatalytic decontamination of organic pollutants is an environmentally friendly and efficient water treatment *** introduction of vacancies,heterojunctions,and doping can enhance the performance of photocatalysts for such *** this study,N,O double-vacancy Ce-ZnO/g-C_(3)N_(4)S-scheme heterojunction photocatalysts were prepared,It is found that the electron separation and transfer efficiencies are considerably improved by the presence of nitrogen vacancies in graphitic ca rbon nitride(g-C_(3)N_(4))and oxygen vacancies in ZnO,in addition to the S-scheme heterojunction created between the two *** the degradation of methylene blue and ciprofloxacin,the degradation rates exhibited by Ce-ZnO/g-C_(3)N_(4)are significantly higher than those of the g=C_(3)N_(4)/ZnO *** remarkable photocatalytic performance of Ce-ZnO/g-C_(3)N_(4)may result from three key factors;(ⅰ)Ce doping,which produces impurity energy levels;(ⅱ)the generation of electron capture centres by the N and O vacancies;and(ⅲ)the synergistic effect of the S-type heterojunction formed at the interface between the two materials,This study therefore provides new approaches for the use of doping,vacancies,and heterojunctions to induce the efficient degradation of organic pollutants.

关键词： Photocatalysis Vacancy S-scheme Ce-ZnO/g-C_(3)N_(4) Degradation Rare earths

Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua jiang Hua-bing Li Rui Zhang Hao Feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time

The dynamics beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 56-67页

作者： Zhen Liu Li-Hua Wang Yong jiang Ya-Jun Tong Hua-chun Zhu Te Ji Min Chen Zheng jiang Xiang-Jun Wei Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China

The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved *** combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme ***,ED-XAS and SR-IR can be used independently in the two branches of the *** ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample *** exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy *** focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 *** one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be *** distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.

关键词： ED-XAS SR-IR Time-resolved D-line SSRF

Suppression of modulation-induced polarization error in spliceless open-loop fiber optic gyroscope [Invited]

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Chinese Optics Letters 2024年第7期22卷 6-11页

作者： Lin Chen Peitong He Biqiang jiang Jianlin zhao Key Laboratory of Light Field Manipulation and Information Acquisition and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China Zhejiang Lab Hangzhou 311100China

The suppression of polarization cross talk in lead zirconate titanate phase modulators as a key error source has been challenging for open-loop fiber optic gyroscopes(FOGs).We developed a polarization-diversity optical frequency domain reflectometry(OFDR)to measure the distributed modulation polarization error in the *** error contributes 8×10^(−6) rad to FOG’s bias *** a UV-fabricated in-fiberλ/4 wave plate and polarization-mode converter with fiber taper technology,the modulation error has been suppressed by 15 dB in assembled *** approach reduced error with temperature from 25°/h to 0.7°/h,meeting the requirements of control-level gyroscopes with bias errors less than 1°/h.

关键词： fiber optic gyroscope inline wave plate optical frequency domain reflectometry polarization-mode converter

A method to interpret fracture aperture of rock slope using adaptive shape and unmanned aerial vehicle multi-angle nap-of-the-object photogrammetry

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 924-941页

作者： Mingyu zhao Shengyuan Song Fengyan Wang chun Zhu Dianze Liu Sicong Wang College of Construction Engineering Jilin UniversityChangchun130026China College of Geo-Exploration Science and Technology Jilin UniversityChangchun130026China Institute of Engineering Geology and Geohazards Hohai UniversityNanjing210098China

The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses,as well as the hydrodynamic properties of fractured rock *** conventional measurement methods are inadequate for collecting data on high-steep rock slopes in complex mountainous *** study establishes a high-resolution three-dimensional model of a rock slope using unmanned aerial vehicle(UAV)multi-angle nap-of-the-object photogrammetry to obtain edge feature points of *** opening morphology is characterized using coordinate projection and *** central axis is determined using vertical measuring lines,allowing for the interpretation of aperture of adaptive fracture *** feasibility and reliability of the new method are verified at a construction site of a railway in southeast Tibet,*** study shows that the fracture aperture has a significant interval effect and size *** optimal sampling length for fractures is approximately 0.5e1 m,and the optimal aperture interpretation results can be achieved when the measuring line spacing is 1%of the sampling *** fractures in the study area generally have larger apertures than shear fractures,and their tendency to increase with slope height is also greater than that of shear *** aperture of tensile fractures is generally positively correlated with their trace length,while the correlation between the aperture of shear fractures and their trace length appears to be *** of different orientations exhibit certain differences in their distribution of aperture,but generally follow the forms of normal,log-normal,and gamma *** study provides essential data support for rock and slope stability evaluation,which is of significant practical importance.

关键词： Unmanned aerial vehicle(UAV) photogrammetry High-steep rock slope Fracture aperture Interval effect Size effect Parameter interpretation

Permeability and selectivity synergistically enhanced nanofluidic membrane for osmotic energy harvesting

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Carbon Energy 2024年第8期6卷 14-24页

作者： Jundong Zhong Tingting Xu Hongyan Qi Weibo Sun Shuang zhao Zhe zhao Yirong Sun Youliang Zhu Jianxin Mu Haibo Zhang Xuanbo Zhu Zhenhua jiang Lei jiang National and Local Joint Engineering Laboratory for Synthetic Technology of High‐Performance Polymer Jilin UniversityChangchunJilinChina State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchunJilinChina Key Laboratory for Molecular Enzymology and Engineering of Ministry of Education Jilin UniversityChangchunJilinChina CAS Key Laboratory of Bio‐inspired Materials and Interfacial Science Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina

For the porous‐membrane‐based osmotic energy generator,the potential synergistic enhancement mechanism of various key parameters is still controversial,especially because optimizing the trade‐off between permeability and selectivity is still a ***,to construct a permeability and selectivity synergistically enhanced osmotic energy generator,the twodimensional porous membranes with tunable charge density are prepared by inserting sulfonated polyether sulfone into graphene *** of charge density and pore size on the ion transport are explored,and the ionic behaviors in the channel are calculated by numerical *** mechanism of ion transport in the process is studied in depth,and the fundamental principles of energy conversion are *** results demonstrate that charge density and pore size should be matched to construct the optimal ion *** collaborative enhancement strategy of permeability and selectivity has significantly improved the output power in osmotic energy generation;compared to the pure graphene oxide membrane,the composite membrane presents almost 20 times improvement.

关键词： blue energy generator charge tunable graphene oxide ion transport layered nanocomposites

Mechanical Modeling and Analysis of Stability Deterioration of Production Well During Marine Hydrate Depressurization Production

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China Ocean Engineering 2024年第2期38卷 338-351页

作者： SUN Huan-zhao CHANG Yuan-jiang SUN Bao-jiang WANG Kang CHEN Guo-ming LI Hao DAI Yong-guo Centre for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580China School of Petroleum Engineering China University of Petroleum(East China)Qingdao 266580China jiangsu Shuguang Oil Tools Co. LtdTaizhou 225532China

Different from oil and gas production,hydrate reservoirs are shallow and unconsolidated,whose mechanical properties deteriorate with hydrate ***,the formations will undergo significant subsidence during depressurization,which will destroy the original force state of the production ***,existing research on the stability of oil and gas production wells assumes the formation to be stable,and lacks consideration of the force exerted on the hydrate production well by formation subsidence caused by hydrate decomposition during *** fill this gap,this paper proposes an analytical method for the dynamic evolution of the stability of hydrate production well considering the effects of hydrate *** on the mechanical model of the production well,the basis for stability analysis has been proposed.A multi-field coupling model of the force state of the production well considering the effect of hydrate decomposition and formation subsidence is established,and a solver is *** analytical approach is verified by its good agreement with the results from the numerical method.A case study found that the decomposition of hydrate will increase the pulling-down force and reduce the supporting force,which is the main reason for the stability *** higher the initial hydrate saturation,the larger the reservoir thickness,and the lower the production pressure,the worse the stability or even *** work can provide a theoretical reference for the stability maintaining of the production well.

关键词： natural gas hydrate production well depressurization production formation deformation stability deterioration

Clinical and microbiological features of community-acquired and nosocomial bloodstream infections in the surgical department of a tertiary-care hospital in Beijing

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Chinese Medical Journal 2013年第22期126卷 4242-4246页

作者： LU You GUO Peng YE Ying-jiang WANG Hui SHEN Zhan-long WANG Qi zhao chun-jiang GAO Zhi-dong ZHANG Xin CAO Jian jiang Ke-wei WANG Shan Peking Univ Peking Univ Peoples Hosp Dept Surg Gastroenterol Beijing 100044 Peoples R China Peking Univ Peking Univ Peoples Hosp Dept Clin Lab Beijing 100044 Peoples R China Shihezi Univ Affiliated Hosp 1 Dept Hepatobiliary Surg Shihezi 832008 Xinjiang Peoples R China

Background Bloodstream infections （BSls） remain a major cause of morbidity and mortality in patients undergoing surgery. This study aimed at elucidating the clinical characteristics of community-acquired BSIs （CABs） and nosocomial BSIs （nBSIs） in patients admitted to the surgical wards of a teaching hospital in Beijing, China. Methods This cross-sectional study compared 191 episodes of BSIs in 4074 patients admitted to the surgical wards between January 2008 and December 2011. Cases of BSIs were classified as CABs or nBSIs, and the characteristics, relevant treatments, and outcomes of CABs and nBSIs were compared. Results Of the 191 BSIs, 52 （27.2%） and 139 （72.8%）were CABs and nBSIs, respectively. Escherichia coli, coagulasenegative staphylococci, and Klebsiella spp, were the most frequently isolated microorganisms. There were significant differences between CABs and nBSIs with respect to the use of hormonal drugs, ventilation, acute physiology and chronic health evaluation （APACHE） Ⅱand American Society of Anesthesiologists scores, and prevalence of cancer （P 〈0.05）. Empirical antibacterial therapy did not decrease the crude mortality, but multivariate analysis showed that high APACHE Ⅱwas independently associated with a risk of mortality （odds ratio =0.97, 95% confidence interval： 0.93-1.02 for APACHE Ⅱ）. Conclusions We found significant differences in the clinical characteristics of surgical patients with CABs and nBSIs. The outcome of patients seems to be related to hiah APACHE Ⅱ scores.

关键词： bacteremia bloodstream infection, surgery, nosocomial infection, community-acquired injection