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Constraints on generalized Chaplygin gas model including gamma-ray bursts

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 547-557页

作者： Fa-yin Wang Zi-Gao dai Shi Qi Department of Astronomy Nanjing University Nanjing 210093 China Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Joint Center for Particle Nuclear Physics and Cosmology Nanjing University- Purple Mountain Observatory Nanjing 210093 China

Generalized Chaplygin gas （whose equation of state is PGCG = -A/ρGCG^α） was proposed as a candidate for unification of dark energy and dark matter. We investigate constraints on this model with the latest observed data. We test the model with type-Ia supernovae （SNe Ia）, cosmic microwave background （CMB） anisotropy, X-ray gas mass fractions in clusters, and gamma-ray bursts （GRBs）. We calibrate the GRB luminosity relations without assuming any cosmological models using SNe Ia. We show that GRBs can extend the Hubble diagram to higher redshifts （z 〉 6）. The GRB Hubble diagram is well behaved and delineates the shape of the Hubble diagram well. We measure As≡A/ρGCG,0^α＋1 =0.68-0.08^＋0.04（where PGCG,0 is the energy density today） and α=-0.22 -0.13^＋0.15 at the 1σ confidence level using all the datasets. Our results rule out the standard Chaplygin gas model （α = 1） at the 3σ confidence level. The ACDM is allowed at the 2σ confidence level. We find that acceleration could have started at a redshift of z - 0.70. The concordance of the generalized Chaplygin gas model with the age estimate of an old high redshift quasar is found. In addition, we show that GRBs can break the degeneracy between the generalized Chaplygin gas model and the XCDM model.

关键词： gamma-rays bursts -- cosmology theory

Research into tritium and helium-3 contents distributions in steel wall of spherical pressure vessel

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Science China(Technological Sciences) 2011年第6期54卷 1521-1524页

作者： LIU YuanDong yin YiHui TAN Yun SUN yin mei Jun Institute of Structural Mechanics China Academy of Engineering Physics P. O. Box 919-401 Mianyang 621900 China Committee of Science and Technology China Academy of Engineering Physics Mianyang 621900 China

The tritium quantity stored in a steel pressure vessel decreases with time because of helium-3 decay and permeation of tritium into the steel wall of the pressure ***,the tritium quantity permeating into the steel wall also decreases with time due to helium-3 decay and diffusion in and out of the wall of *** and helium-3 in the steel wall will cause hydrogen and helium embrittlement of the wall material,respectively,and thereby change the carrying capacity of the *** contemporarily both decay and permeation of tritium within the vessel and decay and diffusion of tritium having permeated into the wall into consideration,the governing equations of tritium and helium-3 contents in the wall were established and solved,and relevant formulas were *** analytical calculations,curves of tritium and helium-3 contents versus radius and time were theoretically plotted,the contents spatio-temporal distributions laws were obtained,and a law about helium-3 contents distribution in steel wall of a spherical pressure vessel was discovered which was called the law of double helium-3 content.

关键词： steel spherical pressure vessel tritium decay helium-3 diffusion law of double helium-3 content

Electrocatalytic degradation of pesticide micropollutants in water by high energy pulse magnetron sputtered Pt/Ti anode

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Chinese Chemical Letters 2022年第12期33卷 5196-5199页

作者： Yuxin Zeng Siyao Zhang Lifeng yin Yunrong dai School of Environment Beijing Normal UniversityBeijing 100875China School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

The increasing occurrence of pesticide micropollutants highlights the need for innovative water treatment technologies,particularly for small-community and household ***-oxidation is being widely studied in this area,unfortunately,safe,stable and efficient electrocatalytic anodes without released heavy metal ions are still highly *** this study,we fabricated a Pt/Ti anode by high energy pulse magnetron sputtering(HiPIMS-PtTi)which was used to decompose dichlorvos(DDVP)and azoxystrobin(AZX)in *** results show that the reaction rate constant(kENR)on HIPIMS was 35.7 min-1(DDVP)and 41.3 min-1(AZX),respectively,superior to electroplating Pt/Ti anode(EP-PtTi).The identification of radicals(^(·)OH,^(1)O_(2),^(·)O_(2)-)and micro-area analyses evidenced that Pt atoms were embedded into the TiO_(2) lattice on the surface of Ti plate by high-energy ions,which resulted in more adsorbed hydroxyls,and higher production of·OH under polarization ***,the electro-oxidation intermediates of DDVP and AZX were identified and the degradation pathways were speculated:(1)indirect oxidation dominated by·OH attack,and(2)direct electron transfer reaction of pesticides on the anode *** cooperated reactions achieve the complete degradation and highly efficient mineralization of DDVP and AZX.

关键词： Electrocatalysis Magnetron sputtering Pesticide Degradation mechanism Dichlorvos Azoxystrobin

Characteristics of sewage sludge and distribution of heavy metal in plants with amendment of sewage sludge

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Journal of Environmental Sciences 2006年第6期18卷 1094-1100页

作者： dai Jia-yin CHEN Ling ZHAO Jian-fu MA Na Institute of Zoology Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and Engineering Tongji University Shanghai 200092 China

In order to better understand land application of sewage sludge, the characterization of heavy metals and organic pollutants were investigated in three different sewage sludges in Shanghai City, China. It was found that the total concentrations of Cd in all of sewage sludge and total concentrations of Zn in Jinshan sewage sludge, as well as those ofZn, Cu, and Ni in Taopu sludge are higher than Chinese regulation limit of pollutants for sludge to be used in agriculture. Leachability of rig in all of studied samples and that of Cd in Taopu sewage sludge exceed the limit values of waste solid extraction standard in China legislation. Based on the characteristics for three kinds of sewage sludge, a pot experiment was conducted to investigate the effect of soil amended with Quyang sewage sludge on the accumulation of heavy *** Begonia semperfloreas-hybr; Ophiopogon japonicas （L.F.） Ker-Gaw; Loropetalum chindense-var, rubrum; Dendranthema morifolium; Viola tricolor; A ntirrhinum majas; Buxas radicans Sieb; Viburnum macrocephalum; Osmanthas fragrans Lour; Cinnamomum camphora siebold and Ligustrum lucidum ait. Results showed that 8 species of plant survived in the amended soil, and moreover they flourished as well as those cultivated in the control soil. The heavy metal concentration in plants varied with species, As, Pb, Cd and Cr concentration being the highest in the four herbaceous species studied, particularly in the roots of D. morifolium. These plants, however, did not show accumulator of As, Pb, Cd and Cr. The highest concentration of Ni and Hg was found in the roots ofD. morifolium, followed by the leaves ofB. semperflorens-hybr. Levels of Zn and Cu were much higher in D. morifolium than in the other plant species. D. morifolium accumulated Ni, Hg, Cu and Zn, which may contribute to the decrease of heavy metal contents in the amended soil. Treatment with sewage sludge did not significantly affect the uptake of heavy metals by the L. chindense-var, rubrum, ho

关键词： sewage sludge characteristic lixiviation test pot experiments land application

A critical review of ferritin as a drug nanocarrier:Structure,properties,comparative advantages and challenges

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Particuology 2022年第5期20卷 65-84页

作者： Shuang yin Kenneth Davey Sheng dai Yongdong Liu Jingxiu Bi School of Chemical Engineering&Advanced Materials Faculty of EngineeringComputer and Mathematical Sciences.University of AdelaideAdelaideAustralia Department of Chemical Engineering Brunei University LondonUxbridge UB83PHUnited Kingdom State Key Laboratory of Biochemistry Engineering.Institute of Process Engineering Chinese Academy of Sciences.BeijingChina

Ferritin stores and releases iron ions in *** is globally important as a drug *** is because of its unique hollow-spherical structure,desirable stability and biological *** drug-loading approaches plus various functionalization approaches have been developed to improve ferritin in response to differing demands in disease ***,we critically review ferritin drug delivery and evaluate its diverse drug-loading and functionalization approaches,we:(1)Introduce basic structural and property information related to ferritin as a drug nanocarrier;(2)Contrast in detail the different means to load drugs and the selection of drug loading means;(3)Discuss multiple ferritin functionalization approaches,together with related advantages and potential risks;and,(4)Compare ferritin with alternative,commonly-used drug *** conclude that despite that no drugs based on ferritin are commercially available,the market potential for it is significant,and evaluate future research *** from this work will be of immediate benefit and interest to a wide range of researchers and manufacturers for drug delivery using ferritin.

关键词： Ferritin Drug delivery Drug nanocarrier Protein functionalization

Preparation and Acid Catalytic Activity of TiO2 Grafted Silica MCM-41 with Sulfate Treatment

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Chinese Journal of Chemical Physics 2008年第1期21卷 21-26页

作者： dai-shi Guo Zi-feng Ma Chun-sheng yin Qi-zhong Jiang Department of Chemical Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240China

TiO2 grafted silica MCM-41 catalyst with and without sulfate treatment were prepared. The structural and acid properties of these materials were investigated by XRD, N2 adsorption-desorption, element analysis, thermal analysis, Raman and FTIR measurements. Their acid-catalytic activities were evaluated using the cyclization reaction of pseudoionone. It was found that the obtained materials possess well-ordered mesostructure, and the grafted TiO2 components were in highly dispersed amorphous form. T/MCM41 without sulfation contained only Lewis acid sites, while Brφnsted and Lewis acidities were remarkably improved for the sulfated materials ST/MCM41 and d-ST/MCM41. T/MCM-41 was not active for the cyclization reaction of pseudoionone, but ST/MCM-41 and d-ST/MCM-41 possessed favorable catalytic activities. The catalytic performance of ST/MCM-41 was comparable with that of the commercial solid acid catalyst of Amberlyst-15, and better than that of d-ST/MCM-41, although the latter underwent a second TiO2 grafting process and accordingly had higher Ti and S content. The specific surface structure of Si-O-Ti-O-S=O in ST/MCM-41 and the bilateral induction effect of Si and S=O on Si-O-Ti bonds were speculated to account for its higher acid catalytic activity.

关键词： TiO2 grafting Sulfate treatment Silica MCM-41 Acid catalytic activity Cyclization of pseudoionone

Three-dimensional numerical analysis of the interaction of two crossing tunnels in soft clay

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Underground Space 2019年第4期4卷 310-327页

作者： Jin yin-Fu Zhu Bing-Qing yin Zhen-Yu Zhang Dong-mei Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina China Development Bank Sichuan Branch No.120Tiantai RoadGaoxin DistrictChengduSichuan ProvinceChina Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Recently,with the development of underground construction,multi-tunnel engineering has become a matter of concern since the interaction between tunnels at close ranges could cause additional deformation in strata as well as surrounding structures and even serious damage to surface *** tunnel displacement and soil deformation problems can be effectively predicted using numerical methods considering the influence of various factors,such as the anisotropic nature of soft *** this end,the anisotropic elastoplastic constitutive S-CLAY1 is implemented in finite element code to investigate deformation problems in the strata and nearby structures caused by the excavation of *** paper focuses in particular on configurations of two crossing *** 3D numerical simulations using ABAQUS enable successive analyses conducted for tunnels at different spacings(1.5D,2.5D,3.5D and 4.5D,where D is the tunnel diameter)of configurations aligned *** results,including the ground settlement,lining force and moment,and tunnel convergence,are *** each aspect,the most unfavorable case is determined by comparing the results of different *** investigation can provide a reference for multi-tunnels design and construction.

关键词： Multi-tunnels Anisotropy Clay Ground loss Finite element Constitutive relation

Defect-enhanced Photocatalytic Activity of ZnO Micro/nanostructures

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Chinese Journal of Chemistry 2013年第12期31卷 1557-1563页

作者： Yu Wang mei Yan Qinguo Chen yin Peng The Key Laboratory of Functional Molecular Solids Ministry of Education Anhui Key Laboratory of MolecularBased Materials College of Chemistry and Materials Science Anhui Normal University Wuhu 241000 China

ZnO micro/nanocrystals with controlled oxygen defects are successfully prepared through annealing precursors obtained via a simple solvothermal method. The size and surface defects of the as-synthesized ZnO mi- cro/nanocrystals increase with the solvent volume ratio of water/ethanol increasing; the BET surface areas of the corresponding samples decrease during these processes; photoluminescence reveals that the type and concentration of surface defects （oxygen vacancy and interstitial oxygen） are quite different for the samples prepared via different solvent volume ratio of water/ethanol. In addition, it is found that the photocatalytic activity of the synthesized ZnO nanocrystals is mainly dependent on the concentration of surface defects. The sample with more surface defects ex- hibits higher photocatalytic activity toward the degradation of methylene blue （MB）. The possible photocatalytic mechanism is discussed in detail.

关键词： ZnO micro/nanocrystals surface defects photocatalytic activity

Novel Nano-composites SDC–LiNaSO_4 as Functional Layer for ITSOFC

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Nano-Micro Letters 2015年第3期7卷 268-275页

作者： Weiming Lv Ze Tong Yi-mei yin Jiewei yin Zi-Feng Ma Shanghai Electrochemical Energy Devices Research Center School of Chemistry and Chemical Engineering Shanghai Jiao Tong University Shanghai Research and Development Center for Polymer Materials

As an ionic conductive functional layer of intermediate temperature solid oxide fuel cells(ITSOFC), samarium-doped ceria(SDC)–Li Na SO4nano-composites were synthesized by a sol–gel method and their properties were investigated. It was found that the content of Li Na SO4 strongly affected the crystal phase, defect concentration, and conductivity of the composites. When the content of Li Na SO4 was 20 wt%, the highest conductivity of the composite was found to be, respectively, 0.22, 0.26, and 0.35 S cm-1at temperatures of 550, 600, and 700 °C, which are much higher than those of SDC. The peak power density of the single cell using this composite as an interlayer was improved to, respectively, 0.23, 0.39, and 0.88 W cm-2at 500, 600, and 700 °C comparing with that of the SDC-based cell. Further, the SDC–Li Na SO4(20 wt%)-based cell also displayed better thermal stability according to the performance measurements at 560 °C for 50 h. These results reveal that SDC–Li Na SO4 composite may be a potential good candidate as interlayer for ITSOFC due to its high ionic conductivity and thermal stability.

关键词： Nano-composite SDC–Li Na SO4 Ionic conductor Solid oxide fuel cell