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Frontiers of Chemical Science and Engineering 2022年第11期16卷 1632-1642页

作者： Xiyuan Bu Ming Tian hongqing wang Lin wang Liyong Yuan Weiqun Shi Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

Although metal–organic frameworks offer a new platform for developing versatile sorption materials,yet coordinating the functionality,structure and component of these materials remains a great *** depends on a comprehensive knowledge of a“real sorption mechanism”.Herein,a ternary mechanism for U(Ⅵ)uptake in metal–organic frameworks was *** MIL-100s(Al,Fe,Cr)were prepared and studied for their ability to sequestrate U(Ⅵ)from aqueous *** a result,MIL-100(Al)performed the best among the tested materials,and MIL-100(Cr)performed the *** nuclear magnetic resonance technique combined with energy-dispersive X-ray spectroscopy and zeta potential measurement reveal that U(Ⅵ)uptake in the three metal–organic frameworks involves different ***,hydrated uranyl ions form outer-sphere complexes in the surface of MIL-100s(Al,Fe)by exchanging with hydrogen ions of terminal hydroxyl groups(Al-OH_(2),Fe-OH_(2)),and/or,hydrated uranyl ions are bound directly to Al(Ⅲ)center in MIL-100(Al)through a strong inner-sphere *** MIL-100(Cr),however,the U(Ⅵ)uptake is attributed to electrostatic ***,the sorption mechanism is also pH and ionic strength *** present study suggests that changing metal center of metal–organic frameworks and sorption conditions alters sorption mechanism,which helps to construct effective metal–organic frameworks-based sorbents for water purification.

关键词： U(Ⅵ) metal–organic frameworks adsorption mechanism metal node

Numerical study on structure of meso-β scale rainstorm system during IOP523 of HUAMEX

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Chinese Science Bulletin 2002年第20期47卷 1729-1733,1764页

作者： Qingli Wu Min Chen hongqing wang Zuyu Tao Laboratory for Severe Storm Research Department of Atmospheric Science College of Physics Peking University Beijing China

One of the scientific goals of HUAMEX (Torrential Rainfall Experiment over Both Sides of the Taiwan Strait and Adjacent Area), a special project in the National '863' Scientific Project, is to reveal meso-β scale structure of heavy rainfall. However, limited by the observational instruments, the resolution of the data attained from the outfield scientific observation network cannot reveal the meso-β scale structure. A 36-h numerical simulation of heavy rainfall case from May 23 to May 24, 1998 during IOP523 of HUAMEX was performed by the mesoscale numerical model of PSU/NCAR MM5, and the meso-p scale structure of con-vective system was examined based on the model output in this note. The results point out that the meso-β scale features of the heavy rainfall are clear considerably at low, middle and upper levels, respectively. There is a strong ageostrophic feature between the geopotential height field and the wind field on the upper level. The vertical cross sections of 54 km coarse grid and 18 km

关键词： heavy rainfall 3-D structure numerical simulation meso-β scale.

Magnetic resonance perfusion imaging evaluation in perfusion abnormalities of the cerebellum after supratentorial unilateral hyperacute cerebral infarction

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Neural Regeneration Research 2012年第12期7卷 906-911页

作者： Pan Liang Yunjun Yang Weijian Chen Yuxia Duan hongqing wang Xiaotong wang Department of Radiology First Affiliated Hospital of Wenzhou Medical College Wenzhou 325000 Zhejiang Province China Second Affiliated Hospital of Wenzhou Medical College Wenzhou 325000 Zhejiang Province China

Magnetic resonance imaging （MRI） data of 10 patients with hyperacute cerebral infarction （≤6 hours） were retrospectively *** patients exhibited perfusion defects on negative enhancement integral maps,four patients exhibited perfusion differences in pseudo-color on mean time to enhance maps,and three patients exhibited perfusion differences in pseudo-color on time to minimum *** susceptibility contrast-enhanced perfusion weighted imaging revealed a significant increase in region negative enhancement integral in the affected hemisphere of patients with cerebral *** results suggest that dynamic susceptibility contrast-enhanced perfusion weighted imaging can clearly detect perfusion abnormalities in the cerebellum after unilateral hyperacute cerebral infarction.

关键词： magnetic resonance imaging magnetic resonance-perfusion-weighted imaging cerebral infarction cerebral perfusion functional neurological deficit

Transfer and Transformation of Soil Iron and Implications for Hydrogeomorpholocial Changes in Naoli River Catchment, Sanjiang Plain, Northeast China

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Chinese Geographical Science 2011年第2期21卷 149-158页

作者： JIANG Ming LU Xianguo wang hongqing ZOU Yuanchun WU Haitao Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China National Wetland Research Center USGS Lafayette Louisiana 70506 USA

Wetland soils are characterized by alternating redox process due to the fluctuation of waterlogged conditions. Iron is an important redox substance, and its transfer and transformation in the wetland ecosystem could be an effective indicator for the environment changes. In this paper, we selected the Naoli River catchment in the Sanjiang Plain, Northeast China as the study area to analyze the dynamics of transfer and transformation of soil iron, and the relationship between iron content change and environmental factors. The results show that the total and crystalline iron contents reach the peak in the depth of 60 cm in soil profile, while the amorphous iron content is higher in the topsoil. In the upper reaches, from the low to high landscape positions, the total and crystalline iron contents decrease from 62.98 g/kg to 41.61 g/kg, 22.82 g/kg to 10.53 g/kg respectively, while the amorphous iron content increases from 2.42 g/kg to 8.88 g/kg. Amorphous iron content has positive correlation with organic matter and soil water contents, while negative correlation with pH. Moreover, both the crystalline and amorphous iron contents present no correlation with total iron content, indicating that environmental factors play a more important role in the transfer and transformation of iron other than the content of the total iron. Different redoximorphic features were found along the soil profile due to the transfer and transformation of iron. E and B horizons of wetland soil in the study area have a matrix Chroma 2 or less, and all the soil types can meet the criteria of American hydric soil indicators except albic soil.

关键词： wetland soil landscape position hydrogeomorpholocial condition redoximorphic feature iron

One-pot synthesis of arginine modified hydroxyapatite carbon microsphere composites for efficient removal of U(Ⅵ) from aqueous solutions

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Science Bulletin 2017年第23期62卷 1609-1618页

作者： Dongxu Yang Xiangxue wang Gang Song Guixia Zhao Zhe Chen Shujun Yu Pengcheng Gu hongqing wang Xiangke wang College of Environmental Science and Engineering North China Electric Power University School of Chemistry and Chemical Engineering University of South China Guangdong Provincial Key Laboratory of Radionuclides Pollution Control and Resources Guangzhou University

Uranium was not only the main source of nuclear energy but also one of the long-lived ***, a novel arginine modified hydroxyapatite carbon microsphere composites(defined as C@HAp/Arg) obtained promptly via a one-step mild hydrothermal method, was applied to remove U(Ⅵ) from aqueous solutions. Based on the characterization of transmission electron microscopy(TEM), scanning electron microscopy(SEM), Fourier transformed infrared spectroscopy(FT-IR), X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS), the synthesized C@HAp/Arg presented globular morphology and abundant functional groups(e.g., —COO^-), which were beneficial to its combination with U(Ⅵ). The interaction mechanism and removal capability of U(Ⅵ) on C@HAp/Arg were studied by batch adsorption technique and spectroscopy analysis. The results implied that U(Ⅵ) can form strong surface complexes on C@HAp/Arg. The kinetics adsorption of U(Ⅵ) followed pseudo-second-order kinetic model with high removal efficiency($95% within 5h at pH 5.0). The adsorption isotherms were well fitted by Langmuir model, implying that U(Ⅵ) uptake on C@HAp/Arg was monolayer coverage. It was found that the maximum adsorption capacities of CSs, C@HAp and C@HAp/Arg toward U(Ⅵ) were calculated to be 23.16,72.09 and 569.66 mg/g, respectively, at 298.15 K and pH 5.0, and thermodynamic parameters revealed that the adsorption processes of U(Ⅵ) were spontaneous and endothermic. In addition, effect of co-existed ions and CO_3^(2-)concentrations demonstrated that U(Ⅵ) adsorption on C@HAp/Arg was weakly interfered by foreign ions and carbonate concentrations. More importantly, the adsorption performance of U(Ⅵ) on C@HAp/Arg was still over $87% after five cycles. Therefore, it was noted that the versatile C@HAp/Arg could be potentially used as a powerful building block for the enrichment and disposal of U(Ⅵ) from aqueous solutions, which could efficiently reduce the potential toxicity of U(Ⅵ) in the U(Ⅵ)-contaminated wate

关键词： U(Ⅵ) C@HAp/Arg composites Interaction mechanism Adsorption

Application of graphene oxides and graphene oxide-based nanomaterials in radionuclide removal from aqueous solutions

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Science Bulletin 2016年第20期61卷 1583-1593页

作者： Xiangxue wang Shujun Yu Jie Jin hongqing wang Njud S. Alharbi Ahmed Alsaedi Tasawar Hayat Xiangke wang School of Environment and Chemical Engineering North China Electric Power University Beijing 102206 China School of Chemistry and Chemical Engineering University of South China Hengyang 421001 China Biotechnology Research Group Department of Biological Sciences Faculty of Science King Abdulaziz UniversityJeddah 21589 Saudi Arabia NAAM Research Group Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia

With the fast development of nanoscience and nanotechnology,the nanomaterials have attracted multidisciplinary *** high specific surface area and large numbers of oxygen-containing functional groups of graphene oxides(GOs) make them suitable in the preconcentration and solidification of radionuclides from *** this paper,mainly based on the recent work carried out in our laboratory,the efficient elimination of radionuclides using GOs and GO-based nanomaterials as adsorbents are summarized and the interaction mechanisms are discussed from the results of batch techniques,surface complexation modeling,spectroscopic analysis and theoretical *** review is helpful for the understanding of the interactions of radionuclides with GOs and GO-based nanomaterials,which is also crucial for the application of GOs and GO-based nanomaterials in environmental radionuclide pollution management and also helpful in nuclear waste management.

关键词： Graphene oxides Radionuclides Sorption Interaction mechanism Theoretical calculation Spectroscopic analysis

Fatigue Magnification Factors of Arc-Soft-Toe Bracket Joints

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Journal of Ocean University of China 2018年第3期17卷 527-534页

作者： FU Qiang LI Huajun wang hongqing wang shuqing LI Dejiang LI Qun FANG Hui College of Engineering Ocean University of China Qingdao 266100 China CIMC RAFFLES Yantai 264000 China School of Aerospace Engineering Xi'an Jiaotong University Xi'an 710049 China

Arc-soft-toe bracket(ASTB), as a joint structure in the marine structure, is the hot spot with significant stress concentration, therefore, fatigue behavior of ASTBs is an important point of concern in their design. Since macroscopic geometric factors obviously influence the stress flaws in joints, the shapes and sizes of ASTBs should represent the stress distribution around cracks in the hot spots. In this paper, we introduce a geometric magnification factor for reflecting the macroscopic geometric effects of ASTB crack features and construct a 3D finite element model to simulate the distribution of stress intensity factor(SIF) at the crack endings. Sensitivity analyses with respect to the geometric ratio Ht/Lb, R/Lb, Lt/Lb are performed, and the relations between the geometric factor and these parameters are presented. A set of parametric equations with respect to the geometric magnification factor is obtained using a curve fitting technique. A nonlinear relationship exists between the SIF and the ratio of ASTB arm to toe length. When the ratio of ASTB arm to toe length reaches a marginal value, the SIF of crack at the ASTB toe is not influenced by ASTB geometric parameters. In addition, the arc shape of the ASTB slope edge can transform the stress flowing path, which significantly affects the SIF at the ASTB toe. A proper method to reduce stress concentration is setting a slope edge arc size equal to the ASTB arm length.

关键词： Arc-soft-toe bracket stress intensity factor geometric magnification factors

Enhanced low-humidity performance of proton-exchange membrane fuel cell by introducing hydrophilic CNTs in membrane electrode assembly

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Progress in Natural Science:Materials International 2022年第2期32卷 150-156页

作者： Sanying Hou hongqing wang Jianwei Ren Chen Yao Lang Shi Shijun Liao School of Chemistry and Chemical Engineering University of South China Energy Centre Council for Scientific and Industrial Research (CSIR) School of Chemistry and Chemical Engineering South China University of Technology

Hydrophilic carbon nanotubes(HCNTs) were introduced into the membrane electrode assembly(MEA) to improve its low-humidity *** effects of types,placement,loading,and relative humidity on the MEA performance were *** has been found that the MEA with 20 wt% HCNTs loading both in anode and cathode achieved the best self-humidifying *** current density reached 1550 mA cm-2at 0.6 V,with a maximum power density of 953 mW/cm~2 at 70℃,30 psi and 30% relative humidity ***,the stability test shows that its current density at 0.6 V only decreased by 6.4% after 44 h performance test,while the performance of blank MEA without HCNTs decreased by 45% within 6 h testing *** extraordinary performance under low humidity condition is ascribed to that the HCNTs contained in the MEA improve the water management and mass transportation by functioning as a dispersant and hydrophilic agent.

关键词： Membrane electrode assembly Low humidity Carbon nanotubes Power density Stability

Design and simulation analysis of high-temperature heat-storage combined-circulation system

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Clean Energy 2022年第1期6卷 77-88页

作者： Hongwei Zhang Junqing Liu Wenbin Liang hongqing Shanand Jie wang National Institute of Clean and Low Carbon Energy Changping DistrictBeijing 102211China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 10084China

In view of the continuous increase in the proportion of renewable energy connected to the grid in China and the increasing peak-to-valley difference in electricity demand on the power grid,this paper proposes a high-temperature thermal-storage combined-cycle power-generation *** Thermoflex thermal simulation analysis software,a high-temperature thermal-storage combined-cycle simulation analysis system model was established,and the influence of different initial temperatures and pressure ratios on the combined-cycle system was *** analysis of factors such as electricity cost,annual operating hours,initial equipment investment,unit efficiency and other factors that affect the net income of the system was carried *** to the current power-peak-shaving auxiliary service market in China,it is pointed out that high-temperature thermal-storage combined-cycle projects must be profitable and obtain good economic *** results obtained,on the one hand,provide suggestions for the flexibility and transformation of current gas-fired steam generators for peak shaving and,on the other hand,provide references for the subsequent development of high-temperature thermal-storage combined-cycle demonstration projects.

关键词： high temperature thermal-energy storage combined cycle economy

Numerical simulation on mesoscale convective system along Mei-Yu front in Southern China

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Chinese Science Bulletin 2000年第22期45卷 2093-2096,2114页

作者： ZHANG Qinghong Kai-Hon LAU wang hongqing CHEN Shoujun National Key Laboratory for Severe Storm Research Department of GeophysicsPeking UniversityBeijing 100871China Center for Coastal and Atmospheric Research The Hong Kong University of Science and TechnologyHong KongChina

A mesoscale convective system (MCS) was generated over the South China Sea at arouna 115°E, 21°N on 0000 UTC 7 June 1998. Riding along the Mei-Yu front, the system moved through the Taiwan Strait and finally hit the southern part of the Taiwan Island, produced over 300 mm of rainfall over parts of Taiwan in the next 24 hours. It was found that the Penn State-NCAR Mesoscale Model Version 5 (MM5) did quite well in simulating the evolution of the MCS. Diagnostic studies on the mesoscale structure of MCS, moisture concentration process and the momentum budget were based on the model output. The concept model of the MCS in the mature phase can be concluded as the following: At the 850 hPa level, the mesoscale low level jet (mLLJ) was found to the southwest of the MCS, which was also associated with a mesoscale low generated by convection, the mesoscale upper level jet (mULJ) was found due east of the MCS (and an upper-level mesoscale high) at the 300 hPa level. Horizontal advection of momentum acted to

关键词： Mei-Yu front MCS mLLJ mULJ.