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Nuclear Science and Techniques 2016年第2期27卷 35-43页

作者： Qiang Zhang Tai-wei chu Beijing National Laboratory for Molecular Sciences Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science College of Chemistry and Molecular Engineering Peking University

^(99m)Tc-BnAO, as a nonnitroaromatic hypoxia marker, is the subject of intensive research in recent years. In this study, a butene amine oxime–nitrotriazole(Bn AO–NT)was synthesized and radiolabeled with ^(99m)Tc in high *** uptakes of^(99m)Tc-Bn AO–NT and ^(99m)Tc-Bn AO were tested using murine sarcoma S180 and hepatoma H22 cell lines. The highest hypoxic cellular uptake of^(99m)TcBn AO–NT was 27.11 ± 0.73 and 14.85 ± 0.83 % for the S180 and H22 cell lines, respectively, whereas the normoxic cellular uptake of the complex was about 4–8 % for both cell lines. For^(99m)Tc-Bn AO, the highest hypoxic cellular uptake was 30.79 ± 0.44 and 9.66 ± 1.20 % for the S180 and H22 cell lines, respectively, while the normoxic cellular uptake was about 5 % for both cell lines. Both^(99m)Tc-Bn AO–NT and^(99m)Tc-Bn AO complexes showed hypoxic/normoxic differentials in the two cell lines, but the results were more significant for the S180 cell line. The in vitro results suggested that S180 may be better than H22 cell line in hypoxic biological evaluation of Bn AO complexes. The biodistribution study was tested using a S180 tumor model. The complex^(99m)Tc-Bn AO–NT showed a selective enrichment in tumor tissues: At 4 h, the tumor-to-muscle ratio was 3.79 ± 0.98 and the tumor-to-blood ratio was 2.31 ± *** with the results of ^(99m)Tc-Bn AO, the latter was at the same level. In vitro and in vivo studies demonstrated that ^(99m)Tc-Bn AO–NT could be a hypoxia-sensitive radiotracer for monitoring hypoxic regions in a sarcoma S180 tumor.

关键词：细胞缺氧肿瘤模型生物学评价标记合成胺肟丁烯 S180

Effects of carrier and Mn loading on supported manganese oxide catalysts for catalytic combustion of methane

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Journal of Natural Gas Chemistry 2008年第2期17卷 159-164页

作者： Jinyan Hu wei chu Limin Shi Department of Environmental Science and Engineering Sichuan University Chengdu 610065 Sichuan China Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China

Supported manganese oxide catalysts were prepared by incipient wetness impregnation method for methane catalytic combustion, and effects of the support （Al2O3, SiO2 and TiO2） and Mn loading were investigated. These catalysts were characterized with N2 adsorption, X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction techniques. Methane conversion varied in a large range depending on supports or Mn loading. Al2O3 supported 15% Mn catalyst exhibited better activity toward methane catalytic oxidation. The manganese state and oxygen species played an important role in the catalytic performance,

关键词： methane catalytic combustion manganese oxide catalyst support effect alumina

Formation of AgI/Ag_3PO_4 solid solution on alumina for enhancing radioactive iodine adsorption at high temperatures

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Nuclear Science and Techniques 2018年第5期29卷 25-35页

作者： Xin Wang Tai-wei chu Beijing National Laboratory for Molecular Sciences Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science College of Chemistry and Molecular Engineering Peking University

Radioiodine-131 is one of the pernicious radionuclides released during nuclear accidents, as its radioactivity can potentially affect public health and *** prevent radioiodine-131 from being released into the environment, the use of adsorbents that are highly efficient at high temperatures is significantly important. The radioactive gas from the nuclear core in an accident, such as the Fukushima nuclear accident, is usually released occurs under high-temperature conditions. Therefore, in this study, a 10 wt% silver phosphate-loaded alumina(Ag_3 PO_4/Al_2 O_3) adsorbent was prepared. Further, its performance toward radioiodine adsorption was tested at high temperatures up to 750 0 C, using Al_2 O_3 and traditional 10 wt% Ag/Al_2 O_3 adsorbent as controls. The results of the iodine adsorption test indicated that the 10 wt% Ag_3 PO_4/Al_2 O_3 adsorbent showed a higher decontamination factor than did the 10 wt% Ag/Al_2 O_3 adsorbent by two orders of magnitude at 650 and 750℃. Results of the iodine desorption test revealed that the new adsorbent could be effectively used at 750 ℃. The characteristic powder X-ray diffraction, nitrogen adsorption-desorption isotherm,X-ray photoelectron spectroscopy, and thermogravimetric analysis-differential scanning calorimetry data indicated that the enhanced adsorption ability at high temperatures was attributed to the formation of a solid solution between silver iodide and Ag_3 PO_4.

关键词： Nuclear accident Radioiodine Solid adsorbent High-temperature adsorption

Catalytic properties of Cu-Co catalysts supported on HNO_3-pretreated CNTs for higher-alcohol synthesis

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Journal of Natural Gas Chemistry 2011年第1期20卷 48-52页

作者： Limin Shi wei chu Siyu Deng School of Materials and Chemical Engineering Xi＇an Technological University Xi＇an 710032 Shanxi China School of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China

HNO 3 -pretreated CNTs were employed as supports, and a special ultrasound-assisted impregnation method was designed to prepare supported Cu-Co catalysts for higher-alcohol synthesis from syngas. The catalysts used in this work were characterized by N 2 adsorption-desorption, TEM, XRD, H 2 -TPR, CO-TPD techniques. It was found that the pre-treatment procedure of CNTs remarkably promoted the catalytic properties of the Cu-Co/CNTs catalysts. For the Cu-Co catalyst supported on CNTs pre-treated by 68 wt% HNO 3 , some active components were introduced into the CNTs channels, their dispersions and the amount of strongly adsorbed CO-species were improved. The CO conversion and alcohol yield on the HNO 3 -pretreated Cu-Co/CNTs catalyst were increased by ～21% and ～69%, respectively, compared with those on the normal Cu-Co/CNTs catalyst.

关键词： HNO 3 -pretreated CNTs Cu-Co/CNTs catalysts CO hydrogenation higher-alcohols

Optical microscopy approaches angstrom precision,in 3D!

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Light(Science & Applications) 2019年第1期8卷 60-61页

作者： Shi-wei chu Department of Physics and Molecular Imaging Center Taiwan University

By coupling dye molecules with a graphene layer and localizing the molecules through quantification of fluorescence lifetime quenching,a novel imaging system offers unprecedented 1-nm resolution with angstrom precisio... 详细信息

关键词： lifetime precision quenching

Ultrathin nanosheets of cobalt-nickel hydroxides hetero-structure via electrodeposition and precursor adjustment with excellent performance for supercapacitor

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Journal of Energy Chemistry 2018年第2期27卷 591-599页

作者： Min wei Qingsong Huang Yanping Zhou Zhu Peng wei chu School of Chemical Engineering Sichuan University School of Electronics and Information Engineering Sichuan University

A homogeneous better-dispersed ultrathin nanosheets（ca. 5 nm） of cobalt-nickel layered double hydroxides（LDH） supported on nickel foam scaffold was synthesized using controllable electrodeposition approach for high efficiency electrode materials of new supercapacitor. The morphology and electrochemical performances of the samples can be controlled by adjusting the precursor ratio, i.e., Ni（OAc）2/Co（NO3）2 molar ratio in the electrodeposition approach. With the increase of this molar ratio, the electrochemical performances give a volcano trend. When the optimized molar ratio is 0.64/0.36, the hybrid delivered a high specific capacitance of 1587.5 F g-1 at a current density of 0.5 A g-1, with good rate capability（1155 F g-1 was retained even at 10 A g-1） and a robust recycle stability（remaining 91.5% after 1000 cycles at 5 A g-1）. The good performance could be attributed to the enlarged interlayer spacing, ultrathin nanosheets and synergistic effects between Co（OH）2 and Ni（OH）2. Furthermore, an asymmetric supercapacitor with a high energy density of 34.5 Wh kg-1 at 425 W kg-1 and excellent cycling stability of 85.4% after 5000 charge-discharge cycles at 2 A g-1 was fabricated. We believe that this fantabulous new electrode material would have encouraging applications in electrochemical energy storage and a wide readership.

关键词： Ultrathin nanosheets CoNi layered double hydroxides (LDH) electrode Ni(OAc)2/Co(NO3)2 precursors High performance Electrodeposition Asymmetric supercapacitor

Glow Discharge Plasma-Assisted Preparation of Nickel-Based Catalyst for Carbon Dioxide Reforming of Methane

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Chinese Journal of Chemical Physics 2008年第5期21卷 481-486页

作者： Fang Guo wei chu Jun-qiang Xu Lin Zhong Department of Chemical Engineering Sichuan University Chengdu 610065 China Department of Chemical and Biological Engineering Chongqing Institute of Technology Chongqing 400050 China

A plasma-assisted method was employed to prepare Ni/γ-All2O3 catalyst for carbon dioxide reforming of methane reaction. The novel catalyst possessed higher activity and better coke-suppression performance than those of the conventional calcination catalyst. To achieve the same CH4 conversion, the conventional catalyst needed higher reaction temperature, about 50 ℃ higher than that of the N2 plasma-treated catalyst. After the evaluation test, the deactivation rate of the novel catalyst was 1.7%, compared with 15.2% for the conventional catalyst. Different from the characterization results of the calcined catalyst, a smaller average pore diameter and a higher specific surface area were obtained for the plasma-treated catalyst. The variations of the reduction peak temperatures and areas indicated that the catalyst reducibility was promoted by plasma assistance. The dispersion of nickel was also remarkably improved, which was helpful for controlling the ensemble size of metal atoms on the catalyst surface. The modification effect of plasma- assisted preparation on the surface property of alumina supported catalyst was speculated to account for the concentration increase of absorbed CO2. An enhancement of CO2 adsorption was propitious to the inhibition of carbon formation. The coke amount deposited on plasma treated catalyst was much smaller than that on the conventional catalyst.

关键词： Nickel-based catalyst Plasma CO2 reforming of CH4 Coke Adsorption of CO2

Cultivated walnut trees showed earlier but not final advantage over its wild relatives in competing for seed dispersers

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Integrative Zoology 2017年第1期12卷 12-25页

作者： Hongmao ZHANG wei chu Zhibin ZHANG Institute of Evolution and Ecology School of Life SciencesCentral China Normal UniversityWuhanChina State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesBeijingChina

Little is known about seeding regeneration of cultivated trees compared to wild relatives in areas where seed dispersers are ***,we investigated the differences in seed fates of cultivated walnut(Juglans regia)and wild Manchurian walnut(Juglans mandshurica)trees under rodent predation and *** seeds have higher nutritional value(large size,mass and kernel mass)and lower mechanical defensiveness(thin endocarp)than *** *** tracked seeds of *** and *** under both enclosure and field conditions to assess differences in competing for seed dispersers of the two co-occurring tree species of the same *** found that rodents preferred to harvest,eat and scatter-hoard seeds of *** as compared to those of *** of *** were removed and scatter-hoarded faster than those of *** of *** were more likely to be rediscovered by rodents than those of *** results suggest that *** showed earlier dispersal fitness but not the ultimate dispersal fitness over *** in seeding regeneration under rodent mediation,implying that *** has little effect on seeding regeneration of *** in the *** effects of seed traits on seed dispersal fitness may vary at different dispersal stages under animal mediation.

关键词： cultivation plant-rodent mutualism seed dispersal seed trait stage-dependent dispersal

ANISOTROPIC PERMEABILITY EVOLUTION MODEL OF ROCK IN THE PROCESS OF DEFORMATION AND FAILURE

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Journal of Hydrodynamics 2012年第1期24卷 25-31页

作者： WANG Huan-ling chu wei-jiang HE Miao Key Laboratory of Coastal Disaster and Defence Ministry of EducationHohai UniversityNanjing 210098China Hydrochina Huadong Engineering Corporation Hangzhou 310014China Jiangsu Transportation Research Institute CO. LTDNanjing 211112China

The rock permeability is an important parameter in the studies of seepage and stress *** micro-cracks and pores can initiate and grow on a small scale and coalesce to form large-scale fractures and faults under compressive stresses,which would change the hydraulic conductivity of the rock,and therefore,the rock *** rock permeability is,therefore,closely rela-ted with the micro-cracking growing,coalescence,and macro new fracture *** article proposes a conceptual model of rock permeability evolution and a micro kinematics mechanism of micro-cracking on the basis of the basic theory of *** applicability of the established model is verified through numerical simulations of in situ tests and laboratory *** simu-lation results show that the model can accurately forecast the peak permeability evolution of brittle rock,and can well describe the macro-experimental phenomenon before the peak permeability evolution of brittle rock on a macro-scale.

关键词： rock hydraulics micro-mechanics permeability model validation

Effects of Ce/Zr ratio on the structure and performances of Co-Ce_(1-x)Zr_xO_2 catalysts for carbon dioxide reforming of methane

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Journal of Natural Gas Chemistry 2010年第2期19卷 117-122页

作者： Ning Wang wei chu Liqiong Huang Tao Zhang Department of Architecture and Environment Sichuan University Chengdu 610065 Sichuan China Department of Chemical Engineering Sichuan University Chengdu 610065 Sichuan China Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China

The Co-incorporated Ce1-xZrxO2 catalysts were prepared by co-precipitation for carbon dioxide reforming of *** ratio of Ce to Zr was varied to optimize the performances of co-precipitated Co-Ce-Zr-Ox *** prepared catalysts were characterized by various physico-chemical characterization techniques including TPR,X-ray diffraction,N2 adsorption at low temperature,XPS and *** co-precipitated Co-Ce0.8Zr0.2O2 sample containing 16% CoO exhibited a higher catalytic activity among the five catalysts,and the activity was maintained without significant loss during the reaction for 60 *** the conditions of 750 ℃,0.1 MPa,36000 ml/（h gcat）,and CO2/CH4 molar ratio of 1：1,the CO2 conversion over this catalyst was 75% while the CH4 conversion was 67%.The cubic Ce0.8Zr0.2O2 facilitated a higher dispersion and a higher reducibility of the cobalt component,and the apparent activation energy for Co-Ce0.8Zr0.2O2 sample was 49.1 kJ/mol in the CO2/CH4 reforming *** a result,the Co-Ce0.8Zr0.2O2 sample exhibited a higher activity and stability for the reforming of CH4 with CO2.

关键词： Ce1-xZrxO2 carbon dioxide methane dry reforming Co-incorporated catalyst characterization