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Journal of environmental Sciences 2012年第9期24卷 1559-1568页

作者： X.J.lee l.Y.lee l.P.Y.Foo d.g.Hassell department of Chemical and environmental engineering University of Nottingham Malaysia CampusJalan Broga43500 SemenyihSelangor Darul EhsanMalaysia.

The present work covers the preparation of carbon-based nanosorbents by ethylene decomposition on stainless steel mesh without the use of external catalyst for the treatment of water containing nickel ions （Ni2＋）. The reaction temperature was varied from 650 to 850℃, while reaction time and ethylene to nitrogen flow ratio were maintained at 30 rain and 1：1 cma/min, respectively. Results show that nanosorbents synthesised at a reaction temperature of 650℃ had the smallest average diameter （75 nm）, largest BeT surface area （68.95 m2/g） and least amount of impurity （0.98 wt.% Fe）. A series of batch sorption tests were performed to evaluate the effects of initial pH, initial metal concentration and contact time on Ni2~ removal by the nanosorbents. The equilibrium data fitted well to Freundlich isotherm. The kinetic data were best correlated to a pseudo second-order model indicating that the process was of chemisorption type. Further analysis by the Boyd kinetic model revealed that boundary layer diffusion was the controlling step. This primary study suggests that the prepared material with Freundiich constants compared well with those in the literature, is a promising sorbent for the sequestration of Ni2＋ in aqueous solutions.

关键词： adsorption nanosorbent nickel ions isotherms kinetics

Ozone forming potential and sulfur effects on in-use vehicles of the metropolitan area of Mexico City

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2006年第3期7卷 463-471页

作者： SCHIFTeR I. díAZ l. lOPeZ-SAlINAS e. Instituto Mexicano del Petróleo Estudios Ambientales Eje Central Lázaro Cárdenas No. 152 San Bartolo Atepehuacan México D.F. 07730 Mexico

The largest urban areas of Mexico cities have witnessed high levels of air pollution in the past few decades. The most important air pollutants are ozone and paniculate matter with levels that are still far above current air quality standard. In this work we studied exhaust and evaporative emissions of Mexico City metropolitan area （MAMC） vehicles using fuels in which sulfur content was varied from 89×10^-6 to 817×10^-6, and calculated the ozone forming potential of emissions as well as the specific reactivity of the exhaust for each average fleet-fuel combinations. data on emission levels were compared to those obtained in 2000 for the same vintage of vehicles. The almost twofold increase in emissions found could be due to degradation of the exhaust emissions control systems.

关键词： Fuel formulation Ozone forming potential Vehicles emissions Mexico

ReSeARCH ON AS-CAST gRAIN ReFININg TeCHNOlOgY BY INOCUlATINg CleAN STeel WITH TITANIUM OXIde

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Acta Metallurgica Sinica(english letters) 2003年第5期16卷 379-384页

作者： g.g.Cheng M.l.Wang X.e.Yang Y.l.li Y.g.Wang l.Y.Wang P.Zhao UniversityofScienceandTechnologyBeijing Beijing100083China CentralIronandSteelResearchInstitute Beiiing100081China

Precipitation condition and nucleation of Ti2O3 during solidification of clean steel have been studied. The behavior of Ti2O3 during solidification as well as possibility of using Ti2O3 to refine as-cast grains as heterogeneous nucleation sites is discussed. It is shown that Ti2O3 can be formed provided that the steelmaking and solidification process is controlled strictly. And inoculating clean steel with Ti2O3 is an effective way to refine as-cast grains.

关键词： clean steel solidification Ti2O3 precipitation

Neuroimaging of inflammation in alcohol use disorder: a review

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Science China(Information Sciences) 2020年第7期63卷 19-37页

作者： dana e.FeldMAN Katherine l.MCPHeRSON Catherine l.BIeSeCKeR Corinde e.WIeRS Peter MANZA Nora d.VOlKOW gene-Jack WANg National Institute on Alcohol Abuse and Alcoholism National Institute on drug Abuse

Alcohol use disorder(AUd) is a global health concern associated with several *** health problems related to AUd, such as cognitive deficits, have been linked to *** use has been associated with changes in neuroimmune activity, although current literature has yielded mixed results. For example, markers of gliosis, including translocator protein 18-kda(TSPO), proinflammatory cytokines, glutamate(glu), and myo-inositol(mI), are disrupted in the alcohol-dependent brain. Further, neuroinflammatory-related phenomena including membrane turnover, blood brain barrier(BBB) permeability, and adenosine release have also shown alterations in AUd. However, current literature remains inconclusive about the directionality of these changes. Both in vivo and in vitro studies have provided insight on the relationship between alcohol use and neuroinflammatory processes, suggesting considerable treatment potential for alcohol use disorder and its inflammatory comorbidities. Here, we review current neuroimaging literature assessing the impacts of alcohol use on neuroimmune activity in the brain.

关键词： acetate adenosine alcohol use disorder blood brain barrier choline gliosis glutamate myoinositol neuroimaging neuroinflammation

Non-aerated liquid culture promotes shoot organogenesis in eucalyptus globulus labill

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Journal of Forestry Research 2018年第3期29卷 621-627页

作者： T.d.Salla C.dos S.Silva K.l.de g.Machado l.V.Astarita e.R.Santarém laboratory of Plant Biotechnology Faculdade de Biociências Pontifícia Universidade Católica do Rio Grande do Sul

eucalyptus is very recalcitrant to in vitro *** this research, an efficient shoot organogenesis system was developed using 60-day-old plants of eucalyptus globulus grown in vitro and non-aerated liquid medium to improve shoot proliferation. Cultures were initiated with hypocotyls and leaf segments from plantlets cultivated on semisolid 1/2 MS modified medium supplemented with 4.44 μM 6-Benzyladenine(BA) and 16.1 μM 1-Naphthaleneacetic acid(NAA). Calli were transferred to shoot induction medium, with either 0.5 or 2.7 μM NAA. Shoot multiplication was carried out on 4.44 μM BA + 0.5 μM NAA medium, and semisolid and non-aerated liquid systems were compared for improving shoot *** of adventitious shoots was evaluated on medium containing NAA or Indole-3-butyric acid-IBA(5 and16 μM). Callogenesis was obtained from both types of explants, although shoot formation was only obtained from leaf-derived calli. Shoot proliferation on 4.44 μM BA+0.5 μM NAA resulted in the most shoots/***-aerated liquid medium was more efficient in promoting shoot multiplication(53.5 shoots/callus) than was semisolid medium(28.5 shoots/callus). levels of phenolic compounds were significantly reduced in the shoots cultivated in liquid medium. efficient rooting(76%) was obtained using 16 μM IBA.

关键词： Adventitious shoots Callus liquid medium Micropropagation Phenolic compounds Rooting

Xiamen after 20 Years of ecological Transformation

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China Today 2025年第1期74卷 66-68页

作者： ZACHARY g.lUNdQUIST 不详

The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean *** years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian ***,due to the fact that I was in a rush,I did not have the chance to see the whole *** memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this *** years went by until I was able to return to this city *** emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and *** exactly had given this city such vitality?

关键词： ecological Xiamen Transformation

Mountain tips as reservoirs for new rock-fungal entities: Saxomyces gen. nov. and four new species from the Alps

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Fungal diversity 2014年第2期65卷 167-182页

作者： l.Selbmann d.Isola e.egidi l.Zucconi C.gueidan g.S.de Hoog S.Onofri deB Universitàdegli Studi della TusciaLargo dell’UniversitàViterboItaly division of genomic&Microbial diversity Department of Life SciencesNatural History MuseumCromwell roadSW75BD LondonUK CBS-KNAW Fungal Biodiversity Centre Uppsalalaan 83584 CT UtrechtThe Netherlands

As part of a worldwide sampling nine black fungi were isolated from rocks collected in four distinct sites of the Alps at high *** on a nucSSU,nuclSU and mtSSU multi-locus phylogeny,seven of them were found to cluster into a distinct and wellsupported clade in a basal position within the Class *** in other rock fungi these new groups of isolates were characterized by a meristematic growth and a scarcely differentiated morphology with highly melanized and thick-walled toruloid ***,few peculiar characters were also observed as convoluted hyphal tips and the production of spherical *** new genus and species Saxomyces alpinus and ***,are here described based on morphological and molecular data,in a yet to be defined order of the *** remaining two black fungi clustered in Cryomyces,a genus previously exclusively found in rocks from the McMurdo dry Valleys in *** two isolates were genetically distant from other Antarctic Cryomyces species based on ITS sequences,and they showed a peculiar morphology;they are here described as the new species *** and *** of our results on the evolution,adaptation and dispersal of rock-inhabiting fungi under extreme conditions are discussed.

关键词： Microcolonial fungi dothideomycetes extremotolerance Multilocus phylogeny

energy transfer and luminescent properties of Tb^(3+)and Tb^(3+),Yb^(3+)doped CNgg phosphors

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Journal of Rare earths 2022年第9期40卷 1445-1453,I0004页

作者： S.Hau g.Stanciu d.Avram l.gheorghe C.gheorghe National Institute for laser Plasma and Radiation PhysicsSolid State Quantum Electronics Laboratory409 Atomistilor StreetP.O.Box MG-36Magurele077125IlfovRomania

In this work,calcium niobium gallium garnet(Ca_(3)Nb_(1.6875)ga_(3.1875)O_(12)-CNgg)ceramic samples singledoped with Tb^(3+)and co-doped with Tb^(3+)and Yb^(3+)ions were sintered by the solid-state reaction *** structural characterization of the samples was carried out by X-ray diffraction *** optimal concentration of Tb^(3+)ions corresponding to the maximum luminescence in the green spectral range in CNgg:x at%Tb(x=0.1,0.5,1,2,3,4,and 5)was determined to be 4 at%.The timeresolved luminescence of the^(5)d_(4)level(Tb^(3+))in the CNgg:x at%Tb samples was analysed to explore the quenching mechanisms involved in the Tb^(3+)green ***-doped CNgg:4 at%Tb,y at%Yb(y=0.5,2,4,6,8,and 10)ceramics were prepared and *** is shown that CNgg:4 at%Tb,y at%Yb phosphors exhibit intense green luminescence under ultra-violet(UV),visible(VIS),and near-infrared(NIR)excitation,thus demonstrating the presence of simultaneous down-conversion(dC)and upconversion(UC)*** dependence of the UC luminescence intensity on the diode laser pumping power was measured and the results indicate a two-photon process based on cooperative energy transfer(CeT).Under UV excitation,the lifetime of the^(5)d_(4)(Tb^(3+))level slowly increases with increase of Yb^(3+)concentration,suggesting the energy transfer from Yb^(3+)to Tb^(3+)ions,while under NIR excitation,the lifetime of the^(5)d_(4)(Tb^(3+))level decreases with increase of Yb^(3+)ions concentration,indicating the presence of a strong energy transfer from Tb^(3+)to Yb^(3+)*** highest energy transfer efficiency ofη_(eT)≈42%was determined for the CNgg:4 at%Tb,10 at%Yb *** obtained results indicate that CNgg:(Tb^(3+),Yb^(3+))could be efficient new yellowish-green-emitting phosphors.

关键词： Phosphors Tb^(3+)and Tb^(3+)-Yb^(3+)luminescence properties Up-conversion down-conversion Quantum cutting process Rare earths

New method for oblique impact dynamics research of a flexible beam with large overall motion considering impact friction force

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Acta Mechanica Sinica 2016年第4期32卷 720-730页

作者： W.Yuan l.li d.g.Zhang J.Z.Hong School of Science Nanjing University of Science and Technology department of engineering Mechanics Shanghai Jiao Tong University

A flexible beam with large overall rotating motion impacting with a rigid slope is studied in this paper. The tangential friction force caused by the oblique impact is analyzed. The tangential motion of the system is divided into a stick state and a slip state. The contact constraint model and Coulomb friction model are used respectively to deal with the two states. Based on this hybrid modeling method, dynamic equations of the system, which include all states（before, during, and after the collision）are obtained. Simulation results of a concrete example are compared with the results obtained from two other models： a nontangential friction model and a modified Coulomb model. differences in the results from the three models are discussed. The tangential friction force cannot be ignored when an oblique impact occurs. In addition, the results obtained from the model proposed in this paper are more consistent with real movement.

关键词： collision oblique friction stick tangential considering Coulomb constraint coordinate rotating

Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas F.Sadreev Yong li Andrey e.Miroshnichenko School of Physics and electronic Sciences East China Normal University Institute of Acoustics Tongji University l.V.Kirensky Institute of Physics department of Mechanical engineering Rowan University School of engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and Friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to Δl-4,whereΔl embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3d waveguide-resonator,which are evidenced by the vanishing of the linewidth of Fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances