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Community st.ucture of Lumbricidae in beech woodland of the Bieszczady National Park, Southeast.Poland

Pedosphere 2021年第3期31卷 391-397页

作者： Anna MAZUR-PĄCZKA Grzegorz PĄCZKA Joanna KOst.CKA Kevin R.BUTT Marcin JAROMIN Mariola GARCZYŃSKA Agnieszka PODOLAK University of Rzeszów Faculty of Biology and AgricultureDepartment of Natural Theories of Agriculture and Environmental Education1a Cwiklinskiej St.Rzeszów 35-959Poland University of Central Lancashire Forensic and Applied SciencesPreston PR12HEUK Rzeszów University of Technology Faculty of ChemistryDepartment of Biotechnology and Bioinformatics6 Powstancow Warszawy AvenueRzeszów 35-959Poland

As ecosyst.m engineers,earthworms play a key role in the soil ***,due to increasing anthropogenic pressure,soil organisms,including earthworms,are being threatened by habitat *** this st.dy,we undertook a qualitative and quantitative invest.gation of earthworms of the family Lumbricidae in four types of Carpathian beech woodland(Fagetum carpaticum),characterized by their underst.ry vegetation(I,*** drymejae;Ⅱ,***;Ⅲ,***;and IV,***),in the Bieszczady National Park(East.rn Carpathians,Southeast.Poland).At each invest.gated site,soil monoliths(25 cm×25 cm×25 cm)were examined by hand *** were expelled from deep soil layers using a weak formalin solution(0.4%).Depending on the phytocoenosis,7 species of Lumbricidae were identified at each of the sites I,Ⅱ,andⅢand 10 at site *** IV(***)differed significantly(Pwith respect to earthworm biomass(59.71±39.53 g m^(-2))and the Shannon-wiener diversity index(0.52±0.12).Although present three decades ago,the deep-burrowing species Octodrilus transpadanus and the litter-dwelling species Dendrobaena octaedra were not found at site IV in the present *** suspect that these two species may have been displaced by the invasive Lumbricus terrest.is,which was not found at the same site in the *** observations warrant further invest.gation to verify the predicted effects of an invasive earthworm,including the potential effects on soils and other fauna and flora,which have been documented in numerous countries.

关键词： beech forest earthworm invasive species Shannon-wiener diversity index species diversity species dominance

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Anodic behavior of neodymium in acidic AlCl_3-1-ethyl-3-methyl-imidazolium chloride ionic liquid

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Journal of Rare Earths 2015年第7期33卷 776-782页

作者：曲瑞江奕东徐霸津丁晶晶廖成凌国平 College of Materials Science and Engineering Zhejiang University Chengdu green Energy and green Manufacturing Technology R&D Centre

The anodic behavior of neodymium in acidic AlCl3-1-ethyl-3-methyl-imidazolium chloride （AIC13-EMIC） ionic liquid was invest.gated by conducting linear sweep voltammeter and chonopotentiometry. The viscosity of Nd dissolved ionic liquid and the surface morphologies of Nd were characterized using an Ost.ald viscometer and a scanning electron microscope, respectively. The chemical composition of Nd surface was indentified by Raman spectra. The results showed that dissolution of Nd under anodic polarization occurred after the breakdown of oxide films. A viscous layer formed at the interface of Nd/ionic liquid during the galvanost.tic process of 5 and 20 mA/cm^2. The formation of viscous layer was attributed to the accumulation of Nd dissolved AlCl3-EMIC ionic liquid, which had high viscosity. The oxide films could be removed thoroughly and the surface of Nd was homogeneous without etching pits, when viscous layer formed in the anodic process. Otherwise, the surface showed a pitting morphology.

关键词： neodymium ionic liquid AlCl3-1-ethyl-3-methyl-imidazolium chloride anodic process viscous layer rare earths

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Depth Dist.ibutions of Belowground Production, Biomass and Decomposition in Rest.red Tallgrass Prairie

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Pedosphere 2019年第4期29卷 457-467页

作者： Adam C.VON HADEN Mathew E.DORNBUSH Environmental Science and Policy Graduate Program University of Wisconsin- Green Bay Green Bay WI 54311 (USA) Great Lakes Bioenergy Research Center University of Wisconsin-Madison Madison WI 53726 (USA) Department of Natural and Applied Sciences University of Wisconsin- Green Bay Green Bay WI 54311 (USA)

Grasslands st.re large st.cks of soil organic carbon(SOC) in the subsoil, but our knowledge of belowground processes becomes less robust.with depth. Vertically explicit SOC models typically assume that the depth dist.ibution of belowground production follows the depth dist.ibution of belowground biomass, but this assumption has not been test.d. In addition to the effects of soil temperature and moist.re on decomposition, some vertically explicit SOC models implement an intrinsic decrease in belowground decomposition with depth, yet this effect has rarely been observed empirically. we simultaneously measured the depth dist.ibutions of belowground biomass, production, and litter decomposition to assess whether belowground biomass depth dist.ibutions were suitable predictors of belowground production and whether belowground decomposition decreased with soil profile depth. we found that live and total(live +dead) belowground biomass was dist.ibuted relatively more shallowly than total belowground production, and thus total belowground biomass was a biased predictor of the vertical dist.ibution of belowground production. The depth dist.ibution of live roots was found to be the best.predictor of total belowground production depth dist.ibution. Using an intact decay core method,we found that belowground litter decomposition decreased by 49% from 0–10 to 30–40 cm depth, and model-simulated effects of soil temperature and moist.re accounted for only 9% of the observed decrease with depth. Vertically explicit SOC models can be improved with more accurate empirical belowground production depth dist.ibution est.mates, but depth-specific decomposition rates currently implemented in SOC models are necessary to explain observed decreases in belowground litter decay with depth.

关键词： carbon decomposition litter decay model simulation roots soil organic carbon soil organic matter temperate grassland vertical rooting dist.ibutions

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La^(3+) -doped SrBi_2Ta_2O_9 thin films for FRAM synthesized by sol-gel method

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Journal of Rare Earths 2014年第3期32卷 277-281页

作者： V.V.Sidsky A.V.Semchenko A.G.Rybakov V.V.Kolos A.S.Turtsevich A.N.Asadchyi w.st.ek F.Skorina Gomel st.te University JSC ?INTEGRAL? 121A Kazintsa st. Minsk 220108 Belarus Inst.tute of Low Temperature and st.uctures Research PAN Okolna st.2 Wroclaw Poland

This paper discusses the possibility of synthesis of SBTL sol-gel films for use as active layers for non-volatile memory （FRAM）. La-doped SrBi2Ta209 thin films were synthesized by sol-gel method on Pt/TiO2/BPSG/SiO2/Si subst.ates. The st.uctural features of the surface （AFM）, cryst.llization behavior （XRD） during the heating and ferroelectric properties of synthesized films were discussed. It was shown that an optimum surface st.ucture and a high share of perovskite phase of SBTL-films were compared to SBT-films （Theating=800 ℃）. Achieved ferroelectric parameters suggest.d the possibility of using synthesized SBTL sol-gel films in non-volatile memory devices.

关键词： ferroelectric thin films sol-gel method lanthanum ion non-volatile memory rare earths

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Synthesis of neodymium modified CeO_2-ZrO_2-Al_2O_3 support materials and their application in Pd-only three-way catalyst.

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Journal of Rare Earths 2012年第4期30卷 342-349页

作者：彭娜周菊发陈山虎罗秀超陈耀强龚茂初 Key Laboratory of green Chemist.y&Technology of the Minist.y of Education Sichuan University

Ce-Zr-Al-Nd2O3 （CZAN） support materials were prepared by co-precipitation and impregnation methods, respectively. They were characterized by X-ray diffTaction （XRD）, low temperature nitrogen adsorption-desorption, oxygen pulsing technique, H2-temperamre programmed reduction （H2-TPR） and X-ray photoelectron spectroscopy （XPS）. The Pd-only three-way catalyst. （Pd-TwC） supported on these materials were prepared by incipient wetness method and st.died by activity test.. The results demonst.ated that the CZAN supports obtained by the two methods showed better st.uctural, textural and redox properties than the CZA without Nd2O3, and the addition of Nd203 improved the catalytic activity of TwC. Especially, the CZAN-i support prepared by impregnation method had better thermal st.bility and redox property. Meanwhile, the Pd/CZAN-i catalyst.exhibited the best.catalytic performance. XPS measurements indicated that the Nd-modified samples possessed more Ce3＋ and oxygen vacancies on the surface of samples, which led to a better redox property. The excellent redox property of support materials helped to improve the catalytic activity of TwC.

关键词： CeO2-ZrO2-Al2O3 support materials Nd2O3 Ce-O-Nd bonds Pd-only three-way catalyst. redox property rare earths

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Skew t dist.ibution and its moments

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Progress in Natural Science:Materials International 2006年第10期16卷 1033-1037页

作者： Saralees NADARAJAH Arjun K.GUPTA Department of st.tist.cs University of NebraskaLincolnNE 68583USA Department of Mathematics and st.tist.cs Bowling Green State UniversityBowling GreenOH 43403USA

A random variable X is said to have the skew-t dist.ibution if its pdf is f(x) = 2g(x) G(λx ), where g(·) and G (·), respectively, denote the pdf and the cdf of the st.dent' s t dist.ibution with degrees of freedom v. The moments of this dist.ibution appear not to have been st.died in detail. In this paper, we derive general expressions for the nth moment of X by considering the cases v odd and v even separately. These expressions turn out to involve sums of the Gauss hypergeometric function. we also provide closed form expressions for the moments of X for the particular cases v = 2,66666, 10.

关键词： complete elliptical integral of the first.kind complete elliptical integral of the second kind Gauss hypergeometric function moments skew t dist.ibution.

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Synergetic effect of thermo-photocatalytic oxidation of benzene on Pt-TiO_2/Ce-MnO_x

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Journal of Rare Earths 2012年第11期30卷 1106-1111页

作者：任成军周丽娜段银武陈耀强 Key Laboratory of green Chemist.y and Technology of the Minist.y of Education College of ChemistrySichuan University

Pt-TiO2/Ce-MnOx catalyst. were obtained by depositing TiO2 and platinum, respectively, on the Ce-Mn oxides prepared by co-precipitation method. The phases of CeO2 and anatase TiO2 were observed in the catalyst. from X-ray diffraction （XRD） patterns. X-ray photoelectron spectroscopy （XPS） revealed that lattice oxygen and surface active oxygen were found to be the major components of O 1 s. The experiment results showed that the kinetic const.nt of thermo-photocatalysis was 7.6 times of the kinetic const.nt of single photocatalysis, and was 2.29 times of the kinetic const.nt sum of photocatalytic and thermal catalytic reaction.

关键词： thermo-photocatalysis synergetic effect benzene Ce-Mn oxides TiO2 Pt rare earths

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Effects of La_2O_3 contents on the Pd/Ce_(0.8)Zr_(0.2)O_2-La_2O_3 catalyst. for methanol decomposition

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Journal of Rare Earths 2011年第6期29卷 544-549页

作者：李雪张利华张超赵明龚茂初陈耀强 Key Laboratory of green Chemist.y & Technology of Minist.y of Education College of Chemistry Sichuan University

The catalytic behaviors of Pd （1.4 wt.%） catalyst. supported on CeO2-ZrO2 promoted with La2O3 were invest.gated for methanol decomposition. The measurements of inductively coupled plasma emission spectroscopy （ICP）, N2 adsorption-desorption （BET）, powder X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, temperature-programmed reduction （TPR） and oxygen st.rage capacity （OSC） were used to characterize the properties of catalyst.. The catalyst.＇ activities were test.d in a fixed bed continuous flow reactor operating under atmospheric pressure. The Pd/Ce0.8Zr0.2O2-5 wt.%La2O3 catalyst.exhibited the best.activity. The reasons for this were twofold：（1） doping of La improved effectively textural properties of CeO2-ZrO2 oxygen st.rage materials, and （2） Pd/Ce0.8Zr0.2O2-5 wt.%La2O3 possessed super oxygen st.rage property and reducibility due to the exist.nce of lattice defect oxygen or mobile oxygen, which helped to re-oxidize zerovalent Pd0 to a partly oxidized Pdδ＋. By introducing 5 wt.%La2O3, the specific surface area of the sample increased, but declined if further increasing the content of La2O3 to 10 wt.%.

关键词： methanol decomposition palladium CeO2-ZrO2-La2O3 XPS catalyst rare earths

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Syntheses of Alkaline Earth and Lanthanide Cryptates with Pyridine-Based Group

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Journal of Rare Earths 2007年第6期25卷 674-678页

作者：胡学雷邱立陈中黄齐茂潘志权 Key Laboratory for green Chemical Process of Minist.y of Education Wuhan Institute of Technology

New alkaline earth metal cryptates [ML]（NO3）2 ·2H2O （M=Ca^2＋, Sr^2＋, Ba^2＋; L = 1, 4,12,15,18, 26, 31, 39, 42, 43, 44-undecaazapentacyclo- [ 13.***.13.1^6,10 .1^20,24 .1^33,37 ]-tetratetraconta -4, 6, 8, 10（44）, 11, 18, 20, 22, 24（43）, 25, 31, 33, 35, 37（42）, 38-pentadecaene） were synthesized by [2 ＋ 3 ] template condensation of tris（2-aminoethyl） amine with 2, 6-diformylpyridine, and then by transmetallation reactions of the calcium cryptate [CaL] （NO3）2·2H2O with corresponding lanthanide ions; three lanthanide cryptates [ LnL] （NO）3·3H2O （Ln = Eu, Gd, Tb） were synthesized and characterized by physical methods. The cryst.l st.ucture of the terbium cryptate [TbL] （NO）3·3H2O was st.died by X-ray analysis. The central atom was coordinated by three pyridyl and six imino nitrogen atoms and exhibited a dist.rted tricapped trigonal prismatic coordination geometry.

关键词： alkaline earth metal lanthanide cryptate synthesis cryst.l st.ucture rare earths

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Upconversion hollow nanospheres CeF_(3) co-doped with Yb^(3+) and Tm^(3+) for photocatalytic nitrogen fixation

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Journal of Rare Earths 2022年第4期40卷 586-594,I0003页

作者： Minghui Zhong Zhendong wang Da Dai Baozhu Yang Shixiang Zuo Chao Yao Fengqin wu Xiazhang Li Advanced Catalysis and green Manufacturing Collaborative Innovation Center Jiangsu Key Laboratory of Advanced Catalytic Materials and TechnologyChangzhou UniversityChangzhou 213164China w.M.Keck Center for Advanced Microscopy and Microanalysis University of DelawareNewarkDE19716USA

Solar driven nitrogen(N_(2))fixation to synthesize ammonia is a potential alternative for the traditional Haber-Bosch approach to meeting indust.ial demand,but is largely hampered by the difficulties in the harvest.ng of solar energy and activating inert N_(2).In this work,hollow CeF_(3) nanospheres co-doped with activator Tm^(3+)and sensitizer Yb^(3+)(Yb^(3+):Tm^(3+):CeF_(3))were prepared by microwave hydrothermal *** product was employed as a catalyst.for photo-driven N_(2) fixation by adjust.ng the molar ratio of Ce^(3+):Yb^(3+):Tm^(3+).Results show that the porous hollow st.ucture enhances the light-harvest.ng by physical scattering and *** addition,heteroatom doping generates abundant fluorine vacancies(F_(V))which provide abundant active sites for adsorption and activation of N_(2).The sample with molar ratio of CeF_(3):Yb^(3+):Tm^(3+)at 178:20:2 demonst.ates the highest.utilization of solar energy attributed to the st.ongest.upconversion capability of near-infrared(NIR)light to visible and ultraviolet(UV)light,and the NH_(4)+concentration achieves the highest.value of 15.06μmol/(gcat∙h)under simulated sunlight while nearly 6.22μmol/(gcat∙h)under NIR *** st.dy offers a promising and sust.inable st.ategy for the fixation of atmospheric N_(2) using full-spectrum solar energy.

关键词： Rare earth CeF_(3) Hollow st.ucture Upconversion Fluorine vacancy Photocatalytic nitrogen fixation

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