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Journal of Environmental sciences 2018年第7期30卷 77-84页

作者： Santosh Kumar Mohmmad Y.Wani Joonseok Koh Joao M.Gil Abilio J.F.N.Sobral chemistry Center Department of ChemistryUniversity of CoimbraCoimbra 3004-535Portugal department of Organic and Nano System Engineering Konkuk UniversitySeoul 143-701Republic of Korea CFisUC Department of PhysicsUniversity of CoimbraCoimbra 3004-516Portugal

One of today＇s major challenges is to provide green materials for a cleaner environment. We have conducted studies on carbon dioxide（CO2） adsorption and conversion to valuable products by an ecofriendly approach based in chitosan/graphene oxide（CSGO） nanocomposite film. Rheological behavior indicates that the CSGO has a better solvation property than the pure chitosan. An adsorption capacity of 1.0152 mmol CO2/g of CSGO nanocomposite at4.6 bar was observed. The catalytic behavior of the CSGO nanocomposite in the presence of tetra-n-butylammonium iodide（n-Bu4 NI） as co-catalyst was evaluated for the cycloaddition of CO2 to epoxides, to give cyclic carbonates, in the absence of any solvent. These results strongly suggest that the CSGO nanocomposite may open new vistas towards the development of ecofriendly material for catalytic conversion and adsorption of CO2 on industrial scale.

关键词： Chitosan Graphene oxide Adsorption Conversion Carbon dioxide

Two and a Half Thousand Years of Navigation on the Dead Sea

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 432-433页

作者： Aharon OREN department of Plant and Environmental sciences The Institute of Life Sciences The Hebrew University of JerusalemEdmond J.Safra CampusGivat Ram

Today there is a single ship on the Dead Sea:a vessel that makes monthly research *** in earlier periods many kinds of boats sailed the waves of the saltiest of all *** and wooden anchors found on the newly

关键词： Two and a Half Thousand Years of Navigation on the Dead Sea

Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics

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Carbon Energy 2024年第5期6卷 65-80页

作者： Yewon Oh Jayaraman Theerthagiri Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi department of chemistry(BK21 FOUR) Research Institute of Natural SciencesGyeongsang National UniversityJinjuRepublic of Korea Core−Facility Center for Photochemistry and Nanomaterials Gyeongsang National UniversityJinjuRepublic of Korea

We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in *** interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron *** defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline ***_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER *** with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER *** results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural *** addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers.

关键词： acetone H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer

Statefinder Diagnosis for the Extended Holographic Ricci Dark Energy Model without and with Interaction

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Communications in Theoretical Physics 2013年第2期59卷 243-248页

作者：于飞张敬飞 College of sciences Shenyang Aerospace University department of Physics College of Sciences Northeastern University

We apply the statefinder diagnostic to the extended holographic Ricci dark energy (ERDE) model without and with interaction to study their behaviors. We plot the trajectories of various parameters for different cases. It is shown that the non-interacting model does not reach the LCDM point {1, 0 } and the interacting one is favored, because the interaction makes the evolution of the statefinder pair r, s quite different.

关键词： statefinder extended holographic Ricci dark energy interaction

A family of symmetric mixed finite elements for linear elasticity on tetrahedral grids

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Science China Mathematics 2015年第2期58卷 297-307页

作者： HU Jun ZHANG Shang You LMAM and School of Mathematical sciences Peking University department of Mathematical sciences University of Delaware

A family of stable mixed finite elements for the linear elasticity on tetrahedral grids are constructed,where the stress is approximated by symmetric H(div)-Pk polynomial tensors and the displacement is approximated by C-1-Pk-1polynomial vectors,for all k *** main ingredients for the analysis are a new basis of the space of symmetric matrices,an intrinsic H(div)bubble function space on each element,and a new technique for establishing the discrete inf-sup *** particular,they enable us to prove that the divergence space of the H(div)bubble function space is identical to the orthogonal complement space of the rigid motion space with respect to the vector-valued Pk-1polynomial space on each *** optimal error estimate is proved,verified by numerical examples.

关键词： mixed finite element symmetric finite element linear elasticity conforming finite element tetrahedral grid inf-sup condition

Proposed GSSP for the base of Cambrian Stage 9,coinciding with the first appearance of Agnostotes orientalis, at Duibian, Zhejiang, China

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Science China Earth sciences 2009年第4期52卷 434-451页

作者： Loren E. BABCOCK Gabriella BAGNOLI School of Earth sciences The Ohio State University department of Earth sciences of Pisa University

Exposed in natural outcrops near the Duibian Village, Jiangshan County, Zhejiang Province, China, the Duibian B section is proposed as the boundary stratotype for the base of an unnamed stage termed provisionally Cambrian Stage 9. The proposed position of the GSSP is 108.12 m above the base of the Huayansi Formation, at a horizon coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalis. This horizon coincides also with the first appearance of the cosmopoli-tan polymerid trilobite Irvingella angustilimbata. The section fulfills all the requirements for a GSSP, and the horizon can be constrained not only by the primary stratigraphic marker (A. orientalis) but also with secondary biostratigraphic, chemostratigraphic, and sequence-stratigraphic correlation tools. The first appearance of A. orientalis is one of the most readily recognizable levels in Cambrian, and can be correlated with precision to all paleocontinents.

关键词： Cambrian GSSP FAD of Agnostotes orientalis China chronostratigraphy

Trace analysis of mefenamic acid in human serum and pharmaceutical wastewater samples after pre-concentration with Ni-Al layered double hydroxide nano-particles

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Journal of Pharmaceutical Analysis 2014年第5期4卷 331-338页

作者： Hossein Abdolmohammad-Zadeh Fatemeh Morshedzadeh Elaheh Rahimpour department of chemistry Faculty of SciencesAzarbaijan Shahid Madani University35 Km Tabriz-Marageh RoadP.O.Box 53714-161TabrizIran department of chemistry Payame Nour University of Tabriz

In this work, the nickel-aluminum layered double hydroxide （Ni-Al LDH） with nitrate interlayer anion was synthesized and used as a solid phase extraction sorbent for the selective separation and pre-concentration of mefenamic acid prior to quantification by UV detection at λmax ？ 286 nm. Extraction procedure is based on the adsorption of mefenamate anions on the Ni-Al（NO3？） LDH and/or their exchange with LDH interlayer NO3？ anions. The effects of several parameters such as cations and interlayer anions type in LDH structure, pH, sample flow rate, elution conditions, amount of nano-sorbent and co-existing ions on the extraction were investigated and optimized. Under the optimum conditions, the calibration graph was linear within the range of 2-1000 mg/L with a correlation coefficient of 0.9995. The limit of detection and relative standard deviation were 0.6 mg/L and 0.84% （30 mg/L, n ？ 6）, respectively. The presented method was successfully applied to determine of mefenamic acid in human serum and pharmaceutical wastewater samples.

关键词： Mefenamic acid Solid phase extraction Nano-sorbent Nickel-aluminum layereddouble hydroxide Ultraviolet spectroscopy

Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： Edgar López-Martínez Octavio Vázquez-Gómez Héctor Javier Vergara-Hernández Bernardo Campillo Faculty of chemistry Metallurgical Engineering Department Autonomous National University of Mexico National Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

SMOOTHING ESTIMATES OF THE RADIAL SCHRO ¨DINGER PROPAGATOR IN DIMENSIONS n≥2

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Acta Mathematica Scientia 2010年第6期30卷 2103-2109页

作者：李栋张晓轶 department of Mathematics University of Iowa Academy of Mathematics and System sciences Chinese Academy of Sciences

The usual Kato smoothing estimate for the Schrodinger propagator in 1D takes the form ｜｜｜δx｜1/2eitθxxu0｜｜ Lx∞Lt2〈∽｜｜u0｜｜Lx2. In dimensions n ≥ 2 the smoothing estimate involves certain localization to cubes in space. In this paper we focus on radial functions and obtain Kato-type sharp smoothing estimates which can be viewed as natural generalizations of the 1D Kato smoothing. These estimates are global in the sense that they do not need localization in space. We also present an interesting counterexample which shows that even though the time-global inhomogeneons Kato smoothing holds true, the corresponding time-local inhomogeneous smoothing estimate cannot hold in general.

关键词： SchrSdinger equation smoothing estimate

Multiple interface coupling on natural tourmaline enables high-efficiency removal of antibiotic:Superior property and mechanism

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Journal of Environmental sciences 2024年第6期140卷 242-254页

作者： Jingjing Cui Xiangyu Liu Feifan Qie Chengzhe Xie Qingdong He Jian Liu Steven L.Suib Wenbo Wang College of chemistry and Chemical Engineering Inner Mongolia UniversityHohhot 010021China department of chemistry University of ConnecticutStorrsCT 06269-3060United States

Reasonably designing highly active,environmentally friendly,and cost-effective catalysts for efficient elimination of pollutants from water is desirable but ***,an efficient heterogeneous photo-Fenton catalyst tourmaline(TM)/tungsten oxide(WO_(3-x))(named TW10)containing tungsten/boron/iron(W/B/Fe)synergistic active centers and 90%of cheap natural tourmaline(TM)mineral rich in Fe and B *** TW10 catalyst can quickly activate peroxymonosulfate(PMS)to generate massive active free radicals,which may induce the rapid and efficient degradation of tetracycline(TC).The TW10/PMS/Visible light system can effectively degrade up to 98.7%of tetracycline(TC)in actual waters(***,Yellow River,and Yangtze River water),and the catalytic degradation rates reach 1.65,5.569,and 2.38 times higher than those of TM,WO_(3-x),and commercial P25(Degussa,Germany),*** addition,the catalyst can be recycled and reused multiple *** spin resonance spectroscopy(EPR),X-ray photoelectron spectroscopy(XPS),and liquid chromatograph-mass spectrometer(LC-MS)analyses confirm that the synergistic catalytic effect of W/B/Fe sites on the TW10 catalyst accelerates the electron transfer between Fe(Ⅱ)and Fe(Ⅲ),as well as between W(Ⅴ)and W(Ⅵ),and thus promotes the rapid degradation of *** catalytic reaction mechanism and degradation pathway of TC were *** work provides a feasible route for the design and development of new eco-friendly and efficient catalyst.

关键词： Tourmaline(TM) Fenton-like catalyst Tungsten oxide Peroxymonosulfate Antibiotic