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Scalable Ambient Pressure Synthesis of Covalent Organic Frameworks and Their Colorimetric Nanocomposites through Dynamic Imine Exchange Reactions

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Chinese Journal of Polymer Science 2018年第1期36卷 1-1,2-7页

作者： Wei Zhao Jia Qiao Tian-Li ning Xi-kui liu College of Polymer Science and Engineering Sichuan University

A novel scale-up ambient pressure synthetic strategy for the preparation of imine-based covalent organic frameworks（COFs） was proposed through dynamic imine exchange reaction mechanism. The obtained COFs exhibited good crystallinity and much higher porosity comparable to their solvothermally synthesized counterparts. Moreover, under ambient pressure, the COF nanofibers could readily grow on the surface of polyimide films, and the resulted nanocomposite film showed an interesting colorimetric acid-responsive behavior.

关键词： Covalent organic frameworks(COFs) Dynamic imine exchange Ambient pressure synthesis

Corrosion mechanism of Zn-Al-Mg-coated steel in simulated polluted marine atmosphere

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Journal of Iron and Steel Research International 2024年第9期31卷 2294-2307页

作者： Pei-dong ning Li-yuan Xiao Jin Wang Qian-qian liu kui Xiao Research Institute JISCO Hongxing Iron and Steel Co.Ltd.Jiayuguan735100GansuChina Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The corrosion behaviour of zinc–aluminium–magnesium-coated steel in a simulated polluted marine atmospheric environment was ***,an indoor ageing acceleration test was carefully designed by simulating a polluted marine *** objective was to in-depth investigate the corrosion mechanism of Zn–Al–Mg-coated steel exposed to a simulated polluted marine *** experiments were carried out by scanning electron microscopy for micro-morphological characterization,X-ray diffraction,electrochemical impedance spectroscopy and electrodynamic polarization curves for the aged *** analysis of the results obtained after an indoor accelerated ageing test shows that Zn–Al–Mg coatings generate insoluble Zn_(5)Cl_(2)(OH)_(8)·H_(2)O and Zn_(4)SO_(4)(OH)_(6)during the corrosion process,which hinders the diffusion of corrosive substances into the substrate,and the insoluble substances are structurally dense and thus inhibit further ***,this effectively inhibits the occurrence of further corrosion,and thus,Zn–Al–Mg coating can significantly extend the service life of Zn–Al–Mg-coated steel.

关键词： Zn-Al-Mg-coated steel Electrochemical impedance spectroscopy Polarization curve Atmospheric corrosion Marine atmosphere

Kinetics process of Tb(Ⅲ)/Tb couple at liquid Zn electrode and thermodynamic properties of Tb-Zn alloys formation

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Science China Chemistry 2017年第6期60卷 813-821页

作者： LiXia Luo YaLan liu ning liu kui liu JinWen Pang LiYong Yuan ZhiFang Chai WeiQun Shi Laboratory of Nuclear Energy Chemistry Institute of High Energy Physics Chinese Academy of Sciences Key Laboratory of Radiation Physics and Technology Ministry of Education Institute of Nuclear Science and Technology Sichuan University

Electrochemical properties of rare-earth elements in the LiCl-KCl eutectic are important for the pyrometallurgical recycling process of spent nuclear fuels. In this work, the electrochemical properties of Tb(Ⅲ)/Tb(0) couple were studied by the cyclic voltammetry(CV) at a liquid Zn pool electrode. The results showed that this electrochemical reaction is quasi-reversible with mixed reversible diffusion control and the charge transfer control. The diffusion coefficient of Tb(Ⅲ) was determined to be in the order of ~10.5 cm2 s.1. Moreover, kinetic parameters, such as the standard rate constants(ks) and charge transfer coefficient(α) for the electroreduction of Tb(Ⅲ) to Tb(0) at the liquid Zn electrode, were calculated by the Nicholson method at 873 K. Additionally, it was found that Tb-Zn intermetallic compounds were easily to be formed in the measurements. Hence, the reduction process of Tb(Ⅲ)/Tb(0) couple on the Zn-coated Mo electrode was also studied to obtain more information of the Tb-Zn intermetallic compounds. Electrochemical signals stemming from various intermetallic compounds associated with TbZn12, Tb2Zn17, Tb13Zn58, Tb3Zn11, TbZn3, TbZn2 and TbZn, were observed. The thermodynamic data were thereafter estimated by applying the emf method at 823–923 K. The standard formation Gibbs energies and the standard equilibrium constant of each Tb-Zn intermetallic compounds were also calculated. Finally, enthalpies and entropies of formation and the apparent standard potentials of various Tb-Zn intermetallic compounds were also obtained.

关键词： Tb liquid Zn electrode kinetic parameters thermodynamic properties molten salt

Moment-tensor inversion and decomposition for cracks in thin plates

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Chinese Journal of Aeronautics 2021年第4期34卷 352-359页

作者： Yue KONG Min LI Weimin CHEN ning liu Boqi kang School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China College of Mechanical and Electrical Engineering Beijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Space Utilization Technology and Engineering Center for Space UtilizationChinese Academy of SciencesBeijing 100094China

The knowledge of crack type and dislocation orientation is helpful for the lifetime prediction of thin plates on *** moment-tensor inversion utilizes the Acoustic Emission(AE)signals to detect cracks and the source mechanisms can be interpreted by the decomposition of moment *** the traditional moment-tensor inversion is implemented for the AE sources inside infinite elastic bodies,the inversion needs to be modified for the cracks in thin *** this study,the moment tensors of cracks in thin plates are derived and the inversion equation is provided based on the Green's function of second kind.A method of modifying the moment tensors to adapt to the existing decomposition processes and source-type plots is *** employing the Finite Element Method(FEM),the wave fields generated by the AE sources are *** AE sources continuously changing from pure tensile type(Model I)to shear type(Model II)are achieved in the FE models and the moment tensors are *** the comparison between the reference values and recovered solutions,the source type can be accurately identified in the source-type plot and the applicability of the moment-tensor inversion for cracks in thin plates is confirmed.

关键词： Acoustic emission Fatigue Moment tensor Source mechanism Structural health monitoring Thin plate

Modeling and analysis of solar Doppler difference bias with arbitrary rotation axis

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Chinese Journal of Aeronautics 2020年第12期33卷 3331-3343页

作者： Jin liu Yangyang LI Xiaolin ning Xiao CHEN Zhiwei kang College of Information Science and Engineering Wuhan University of Science and TechnologyWuhan 430081China College of Instrument Science and Optoelectronic Engineering Beihang UniversityBeijing 100191China Shanghai Institution of Satellite Engineering Shanghai 200240China College of Information Science and Engineering Hunan UniversityChangsha 410082China

The solar rotation causes the solar Doppler difference bias,which leads to the decline of the velocity measurement *** and compensation are an effective *** limited model with specific geometric direction,where the solar rotation axis is perpendicular to the plane through the Sun,the Earth and Mars,was ***,in fact,the geometric relationship among the Sun,Mars and the spacecraft is not fully in line with the hypothesis of the model due to the spacecraft orbital angle and the solar rotation axis ***,this model is not consistent with the *** order to solve this problem,a universal solar Doppler difference bias model,which provides the expression with arbitrary rotation axis,is established in this *** this method,for any point at the solar surface,four variables including the direction of the solar rotation linear velocity at this point,the distance from this point to the rotation axis,the vector from this point to Mars,and the vector from this point to the spacecraft are *** on these four variables,the solar Doppler difference bias corresponding to this point is *** theoretical analysis and simulation results demonstrate that the solar Doppler difference bias model with the actual rotation axis is different from that with one of the specific rotation ***,it is indispensable to build the proposed model for ***,the direction of the solar rotation axis,the spacecraft-Mars-Sun angle and the spacecraft-to-Mars distance are important impact factors for the proposed model.

关键词： Bias Doppler navigation Measurement Modeling Rotation

Diversity of the Coupling Wheels in the East Asian Summer Monsoon on the Interannual Time Scale: Challenge of Summer Rainfall Forecasting in China

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Advances in Atmospheric Sciences 2021年第4期38卷 546-554页

作者： Congwen ZHU Boqi liu kang XU ning JIANG Kai liu State Key Laboratory of Severe Weather and Institute of Climate SystemChinese Academy of Meteorological SciencesBeijing 100081China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China National Marine Environmental Forecast Center Beijing 100081China

Two types of three-dimensional circulation of the East Asian summer monsoon(EASM) act as the coupling wheels determining the seasonal rainfall anomalies in China during 1979–2015. The first coupling mode features the interaction between the Mongolian cyclone over North Asia and the South Asian high(SAH) anomalies over the Tibetan Plateau at 200 hPa. The second mode presents the coupling between the anomalous low-level western Pacific anticyclone and upperlevel SAH via the meridional flow over Southeast Asia. These two modes are responsible for the summer rainfall anomalies over China in 24 and 7 out of 37 years, respectively. However, the dominant SST anomalies in the tropical Pacific, the Indian Ocean, and the North Atlantic Ocean fail to account for the first coupling wheel's interannual variability, illustrating the challenges in forecasting summer rainfall over China.

关键词： East Asian summer monsoon coupling circulation modes summer rainfall anomalies China

Neoadjuvant chemoradiotherapy followed by laparoscopic distal gastrectomy in advanced gastric cancer: A case report and review of literature

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World Journal of Clinical Cases 2021年第11期9卷 2542-2554页

作者： Zi-ning liu Yin-kui Wang Zi-Yu Li Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education/Beijing) Gastrointestinal Cancer CenterPeking University Cancer Hospital&InstituteBeijing 100142China

BACKGROUND The laparoscopic technique has been widely applied for early gastric cancer,with the advantages of minimal invasion and quick ***,there is no report about the safety and oncological outcome of laparoscopic gastrectomy with D2 lymph node dissection for patients after neoadjuvant *** SUMMARY A 60-year-old man was diagnosed with advanced distal gastric cancer,cT4aN1M0 stage *** neoadjuvant chemoradiotherapy was performed based on the regimen of gross tumor volume 50G y/25 f and clinical target volume 45 Gy/25 f,as well as concurrent S-160 mg *** laparoscopic distal gastrectomy with D2 lymph node dissection was undertaken successfully for him after achieving partial response evaluated by radiological *** patient recovered smoothly without moderate or severe postoperative *** postoperative pathological stage was ypT3N0M0 with American Joint Committee on Cancer tumor regression grade *** was still in good condition after 5 years of *** Neoadjuvant chemoradiotherapy followed by laparoscopic technique could be applicable and may achieve satisfactory oncological *** finding requires further validation by cohort studies.

关键词： Gastric cancer Neoadjuvant chemoradiotherapy Laparoscopic Distal gastrectomy S-1 Case report

Preparation of bimetal Co-Ni supported on Mg-Al oxide for chemocatalytic upgrading of tailored fermentation products to energy intensive fuels

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Green Energy & Environment 2022年第3期7卷 457-466页

作者： Jiajun liu kui Wu Zhengke Li Wensong Li Yuqing ning Weiyan Wang Yunquan Yang School of Chemical Engineering Xiangtan UniversityXiangtanHunan411105China

The great challenge in the aldol condensation of tailored fermentation products(acetone-butanol-ethanol,ABE)into energy intensive fuels is to develop a suitable catalyst with high activity and *** this study,Co,Ni,and Co-Ni supported on Mg-Al oxide catalysts were prepared and their pore diameters were enlarged via adding active carbon as a hard template into Mg-Al *** the aldol condensation reaction,the catalyst activity was enhanced after enlarging the pore diameter and Co-Ni bimetal supported catalyst presented the highest activity,which was resulted from that the electron transfer between Co and Ni in Co-Ni alloy enhanced the dehydrogenation activity and large pore lowered the mass transfer *** optimizing the reaction conditions,acetone conversion and the total selectivity of C_(5)-C_(11)desired products in the aldol condensation of ABE reached up to 76%and 90%,*** stability study showed that the activity was decreased with the increase of reaction number because of the oxidation of metallic Co and Ni,but this could be solved via a simple hydrogen reduction method.

关键词： method catalyst condensation

Neck-spinning quality analysis and optimization of process parameters for plunger components:Simulation and experimental study

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Chinese Journal of Aeronautics 2021年第4期34卷 174-191页

作者： Yang WANG Honghua SU ning QIAN kui liu Jianbo DAI Zhengcai ZHAO Wenfeng DING College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Singapore Institute of Manufacturing Technology 73 Nanyang DriveSingapore 637662Singapore School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China

The plunger component is a key part of the plunger pump in the aircraft hydraulic ***-spinning process is commonly used to fabricate plunger components,of which the quality of the spinning process significantly affects the performance of plunger *** of the bottlenecks faced by the industry in the spinning process is to choose a suitable neck-spinning process so as to ensure the quality of plunger *** is necessary to propose a reliable method to optimize the process parameters which affect the neck-spinning quality of plunger *** this study,a calculable finite element analysis(FEA)model is established to simulate the threeroller neck-spinning process of the plunger component,which includes six typical slipper structures,two roller structures,and two spinning *** FEA model is then validated by comparing the simulated spinning forces with the corresponding experimental *** influence of the process conditions on the neck-spinning quality is *** the orthogonal simulation results are analyzed by a combination of range method and fuzzy mathematical analysis method to recommend a reasonable slipper structure,roller structure and neck-spinning *** study provides a promising method to improve the manufacturing quality of the typical plunger components.

关键词： Fuzzy method Neck-spinning quality Plunger component Range analysis Simulation