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The phosphorescence nanocomposite thin film with rich oxygen vacancy:Towards sensitive oxygen sensor

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Chinese Chemical Letters 2022年第8期33卷 3977-3980页

作者： jian Yao jian kong Lingwei kong Xinrui Wang Wenying Shi Chao Lu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Cosmetic China National Light IndustryBeijing Technology and Business UniversityBeijing 100048China

Organic room temperature phosphorescent(ORTP)materials provide an exciting research direction for phosphorescent oxygen(O_(2)) sensors due to their high sensitivity and rapid response to O_(2).however,most pure ORTP materials are tightly-packed aromatic compound crystals in a face-to-face manner,which largely prohibits effective O_(2) diffusion for ***,how to solve this contradiction still faces huge ***,the use of organic phosphorescent indicator carbon dots(CDs),inorganic matrix layered double hydroxides(LDhs)and polymers(PVA)successfully prepared an ultra-long RTP composite film whose phosphorescence decay intensity is linearly related to O_(2) *** importantly,the use of the abundant O_(2) defects(Vo)on the surface of the inorganic matrix LDhs to adsorb O_(2),which further accelerates the phosphorescence quenching of the thin film and improves the O_(2) *** strategy will provide the possibility to develop high-sensitivity phosphorescent O_(2) sensors from a new perspective.

关键词： Layered double hydroxides Carbon dots Nanocomposite thin film Phosphorescence Oxygen vacancy Oxygen-sensing

Excellent electromagnetic wave absorption of MOF/SiBCN nanomaterials at high temperature

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Chinese journal of Aeronautics 2021年第11期34卷 277-291页

作者： Chunjia LUO Peng MIAO Yusheng TANG jie kong MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Shaanxi Key Laboratory of Macromolecular Science and TechnologySchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Electromagnetic wave absorbing materials at high-temperature are urgently needed for stealth aircrafts or aero-engines worked in harsh *** this contribution,cobaltcontaining siliconboron carbonitride(MOF/SiBCN)nanomaterials were prepared by pyrolyzing metal–organic framework,*** 2-methylimidazole(ZIF-67),and hyperbranched *** rhombic dodecahedral ZIF-67 and cobalt element promoted in situ formation of dielectric loss phases,including SiC nanocrystals,CoSi nanocrystals and turbostratic *** ZIF-67/SiBCN nanomaterials showed excellent microwave absorption both at room and elevated *** minimum reflection coefficient(RC_(min))was-51.6dB and effective absorption bandwidth(EAB)is 3.93Ghz at room *** an elevated temperature of 600℃,the RC_(min) reached-30.29 dB and EAB covered almost the whole X-band(3.95Ghz,8.45–12.4Ghz).The ZIF-67/SiBCN nanocomposites are promising and useful platform for microwave absorbing materials at *** may shed light on the downstream applications in designing next generation areo-engines and stealth aircrafts.

关键词： Electromagnetic wave absorption high temperature resistance Metal-organic framework Polymer-derived ceramics Siliconboron carbonitride

Improving surface integrity of micro-holes in ECDM using ultrahigh-speed rotary of tool cathode and non-water-based electrolyte

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Chinese journal of Aeronautics 2024年第5期37卷 506-519页

作者： jiwen ShEN Weijing kong Zhengyang XU Yongbin ZENG jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

The surface integrity of metal micro-hole structures produced by electrochemical discharge machining is unsatisfactory owing to the insufficient reaction area and strength of electrolysis action.A novel ultrahigh-speed Rotary Electrochemical Discharge Machining(R-ECDM)using non-water-based electrolyte is proposed to improve surface integrity by changing the breakdown medium of spark discharge and increasing the reaction area and strength of electrolysis.A mathematical model was developed to establish the relationship between rotational speed and forces acting on the *** on the magnitude of forces,controlling rotational speed changed the behavior and departure radius of bubbles on the cathode ***-speed photographs validate that,in the mathematical model,the number and departure radius of bubbles on the cathode surface gradually decrease with the increase of rotational *** experimental results show that the roughness(Ra)of the micro-hole sidewall decreases from 2.54μm to 0.20μm when the rotational speed increases from 500 r/min to 40000 r/*** length loss and wear ratio of the cathode are only 9.75μm and 6.5%,***,the micro-holes array with recast-free and surface roughness of 0.20μm is fabricated,demonstrating that the proposed approach contributes to improving surface integrity of metal micro-holes.

关键词： Electrochemical discharge machining Micro-holes Recast layer Ultrahigh-speed rotary Bubbles Force analysis Non-water-based solution

Industrial application prospects and key issues of the pure-hydrogen reduction process

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International journal of Minerals,Metallurgy and Materials 2022年第10期29卷 1922-1931页

作者： Lei Wang Peimin Guo Lingbing kong Pei Zhao State Key Laboratory of Advance Steel Process and Products Central Iron and Steel Research InstituteBeijing 100081China Cisri Sunward Technology Co. Ltd.Beijing 100081China

The industrial application prospect and key issues in basic theory and application are discussed by the methods of theoretical analysis and calculation to promote the development of the pure-hydrogen reduction *** to the discussion of thermodynamics and kinetics of pure-hydrogen reduction reaction,the reduction reaction of iron oxide by pure hydrogen is an endothermic reaction,and the reaction rate of hydrogen reduction is significantly faster than that of carbon *** explore the feasibility of the industrial applications of pure-hydrogen reduction,we design the hydrogen reduction reactor and process with reference to the industrialized hydrogen-rich reduction process and put forward the methods of appropriately increasing the reduction temperature,pressure,and temperature of iron ore into the furnace to accelerate the reaction rate and promote the reduction of iron *** key technical parameters in engineering applications,such as hydrogen consumption,circulating gas volume,and heat balance,are discussed by theoretical calculations,and the optimized parameter values are *** process parameters,cost,advantages,and disadvantages of various current hydrogen production methods are compared,and the results show that hydrogen production by natural gas reforming has a good development *** the discussion of the corrosion mechanism of high-temperature and high-pressure hydrogen on heat-resistant steel materials and the corrosion mechanism of h_2S in the hydrogen gas on steel,the technical ideas of developing new metal temperature-resistant materials,metal coating materials,and controlling gas composition are put forward to provide guidance for the selection of heater and reactor ***,the key factors affecting the smooth operation of the hydrogen reduction process in engineering applications are analyzed,offering a reference for the industrial application of the purehydrogen reduction process.

关键词： pure hydrogen reduction process design engineering application reactor material sulfur and nitrogen balance

1A6/DRIM, the human UTP20 functions in 28S and 5.8S rRNA processing

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Chinese Science Bulletin 2010年第17期55卷 1770-1776页

作者： kong RuiRui hAN Wei ULRICh h. Weidle NING Tao DU Xiaojuan KE Yang Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Genetics Laboratory Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100142 China Cancer Research Center Peking University Health Science Center Beijing 100191 China Roche Diagnostics Gmbh Division Pharma 82372 Penzberg Germany Department of Cell Biology Peking University Health Science Center Beijing 100191 China

1A6/DRIM has been identified as UTP20, a small subunit processome component, functioning in 18S rRNA processing. In the present study, the maturation of 28S rRNA and 5.8S rRNA was inhibited when 1A6/DRIM was silenced in heLa cells; and coincidently, an accumulation of 32S rRNA precursor was observed. Immunoprecipitation was performed with the anti-1A6/DRIM antibody, followed by Northern blot with the ITS2 probe. The results showed that 1A6/DRIM was associated with both 32S and 12S rRNA precursors in vivo. The expression profile of 1A6/DRIM during rRNA processing was investigated by sucrose density gradient fractionation in combination with Western blot analysis. The results demonstrated that 1A6/DRIM was involved in the pre-60S particles in addition to the pre-40S particles and co-sediment with the 32S and 12S rRNA precursors in the nucleolus. Furthermore, the interaction of U8 snoRNA with 1A6/DRIM was revealed by immunoprecipitation. These results demonstrated that 1A6/DRIM interacted with both 32S rRNA and U8 snoRNA, being involved in 28S rRNA and 5.8S rRNA processing.

关键词： rRNA基因加工过程 snoRNA 职能人类 heLa细胞免疫印迹分析免疫沉淀

Selective recovery of Cu(II) from strongly acidic wastewater by zinc dimethyldithiocarbamate: Affecting factors, efficiency and mechanism

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journal of Environmental Sciences 2023年第7期129卷 115-127页

作者： Xin Yang Xingyun hu Linghao kong Xianjia Peng State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China National Engineering Research Center of Industrial Wastewater Detoxication and Resource Recovery Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The selective recovery of copper from strongly acidic wastewater containing mixed metal ions remains a significant *** this study,a novel reagent zinc dimethyldithiocarbamate(Zn(DMDC)_(2))was developed for the selective removal of Cu(II).The removal efficiency of Cu(II)reached 99.6%after 120 min reaction at 30°C when the mole ratio Zn(DMDC)_(2)/Cu(II)was 1:*** mechanism investigation indicates that the Cu(DMDC)_(2) products formed as a result of the displacement of Zn(II)from the added Zn(DMDC)_(2) by Cu(II)in wastewater,due to the formation of stronger coordination bonds between Cu(II)and the dithiocarbamate groups of Zn(DMDC)_(2).Subsequently,we put forward an innovative process of resource recovery for strongly ***,the selective removal of Cu(II)fromactualwastewater using Zn(DMDC)_(2),with a removal efficiency of 99.7%.Secondly,high-value CuO was recovered by calcining the Cu(DMDC)_(2) at 800°C,with a copper recovery efficiency of 98.3%.Moreover,the residual As(III)and Cd(II)were removed by introducing h_(2)S gas,and the purified acidic wastewater was used to dissolve ZnO for preparation of valuable ZnSO_(4)·h_(2)*** total economic benefit of resource recovery is estimated to be 11.54$/m^(3).Accordingly,this study provides a new route for the resource recovery of the treatment of copper-containing acidic wastewater.

关键词： Strongly acidic wastewater Zinc dimethyldithiocarbamate Copper Selective Recovery

Synthesis of hierarchical mesoporous Ln_(2)Ti_(2)O_(7)(Ln=Y,Tb-Yb)pyrochlores and uranyl sorption properties

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journal of Materials Science & Technology 2022年第18期113卷 22-32页

作者： Linggen kong Inna Karatchevtseva Tao Wei Nicholas Scales Australian Nuclear Science and Technology Organisation Lucas Heights NSW2234Australia

Mesoporous structured metal oxides exhibit many active ***,the synthesis of crystalline metal oxides with a ternary composition while maintaining satisfactory pore features is ***,high temperatures are required which inhibit control of pore structure properties including surface area,pore volume,and pore ***,the synthesis of ternary metal oxides Ln_(2)Ti_(2)O_(7)pos-sessing pyrochlore crystal structure is achieved using a novel technique which combines‘soft’and hard colloid templating *** formed materials are of submicron size and composed of∼25-30 nm product‘building blocks’with good chemical and phase *** polycrystalline powders have a high specific surface area(up to 70 m^(2)·g^(-1))and pore volume(∼0.35 cm^(3)·g^(-1))which result in a good adsorp-tion capacity(U uptake closing to 60 mg·g^(-1)).Remarkably,the material exhibits a significant portion of mesopores(mainly 10-40 nm)which facilitate fast adsorption of the cations due to high *** synthetic methodology described herein produces highly homogenous powders and can be applied to other compositions and structures.

关键词： Porous ternary metal oxides Dual template synthesis Lanthanide titanate Pyrochlore Uranium adsorption

Recent progress of machine learning in flow modeling and active flow control

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Chinese journal of Aeronautics 2022年第4期35卷 14-44页

作者： Yunfei Li juntao Chang Chen kong Wen Bao School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In terms of multiple temporal and spatial scales, massive data from experiments, flow field measurements, and high-fidelity numerical simulations have greatly promoted the rapid development of fluid mechanics. Machine Learning(ML) provides a wealth of analysis methods to extract potential information from a large amount of data for in-depth understanding of the underlying flow mechanism or for further applications. Furthermore, machine learning algorithms can enhance flow information and automatically perform tasks that involve active flow control and optimization. This article provides an overview of the past history, current development, and promising prospects of machine learning in the field of fluid mechanics. In addition, to facilitate understanding, this article outlines the basic principles of machine learning methods and their applications in engineering practice, turbulence models, flow field representation problems, and active flow control. In short, machine learning provides a powerful and more intelligent data processing architecture, and may greatly enrich the existing research methods and industrial applications of fluid mechanics.

关键词： Data-driven modeling Flow control Flow field kinematics Machine learning Neural networks-applications

Removal of Ni(Ⅱ) from strongly acidic wastewater by chelating precipitation and recovery of NiO from the precipitates

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journal of Environmental Sciences 2021年第6期33卷 365-375页

作者： Xin Yang Xianjia Peng Linghao kong Xingyun hu State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Beijing Key Laboratory of Industrial Wastewater Treatment and Resource Recovery Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Strongly acidic wastewater produced in nonferrous metal smelting industries often contains high concentrations of Ni(Ⅱ), which is a valuable metal. In this study, the precipitation of Ni(Ⅱ) from strongly acidic wastewater using sodium dimethyldithiocarbamate(DDTC) as the precipitant was evaluated. The effects of various factors on precipitation were investigated, and the precipitation mechanism was also identified. Finally, the nickel in the precipitates was recovered following a pyrometallurgical method. The results show that, under optimised conditions(DDTC:Ni(Ⅱ) molar ratio = 4:1;temperature = 25 ℃), the Ni(Ⅱ) removal efficiency reached 99.3% after 10 min. In strongly acidic wastewater, the dithiocarbamate group of DDTC can react with Ni(Ⅱ) to form DDTC –Ni precipitates. Further recovery experiments revealed that high-purity Ni O can be obtained by the calcination of DDTC –Ni precipitates, with the nickel recovery efficiency reaching 98.2%. The gas released during the calcination process was composed of NO_(2), CS_(2), h_(2)O, CO_(2), and SO_(2). These results provide a basis for an effective Ni(Ⅱ) recovery method from strongly acidic wastewater.

关键词： Strongly acidic wastewater Ni(Ⅱ) Recovery Chelation Precipitation