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Are some communities of the coastal dune zonation more susceptible to alien plant invasion?

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Journal of plant Ecology 2010年第2期3卷 139-147页

作者： M.Carboni r.Santoro A.T.r.Acosta Dipartimento di Biologia Ambientale Universita`degli Studi di Roma TreViale Marconi 44600146 RomaItaly

Aims Coastal areas,and in particular coastal dunes,are ecosystems strongly affected by the invasion of alien ***,few attempts have ever been made to quantify alien species incidence in different communities along the coastal *** work aims to analyze the distribution of alien plants along the coastal zonation of sandy shores on the Tyrrhenian coast,addressing specifically differences among plant communities in abundance of alien *** The study was performed on recent dunes(Holocene)of the central western coast of *** selected dune landscapes where invasion processes were particularly *** plots were randomly sampled and through cluster analysis,we identified six plant communities corresponding to the typical zonation described for the Tyrrhenian sandy coast of Central *** evaluated and compared frequency and abundance of invasion in these different ***,we investigated how propagule pressure(measured using as proxy human structures)contributed to the observed invasion *** Findings We found a relatively low total number of aliens but also a differential distribution pattern and strong abundance of some of the aliens in specific sectors of the vegetation *** perennial community of transition dunes appears most affected by invasion processes,related almost exclusively to the frequent and widespread Carpobrotus *** alien species reaches high cover values,apparently lowering cover of native species of transition dune plant *** levels of invasion in the transition dune can be partially explained because of greater propagule pressure in this section of the dune *** findings thus have important conservation and management implications since transition dune communities with Crucianella maritima are rare and protected(sensu Habitat 92/43/EEC Directive)along the entire Italian coast.

关键词： level of invasion propagule pressure Carpobrotus aff.acinaciformis Central Italy coastal communities

ATp translocation and chloroplast biology

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National Science review 2019年第6期6卷 1073-1076页

作者： Chia p.Voon Boon L.Lim School of Biological Sciences University of Hong Kong

By studying changes in ATp levels in the plastids and cytosol of live plants using a Mg ATp2-specific F?rster resonance energy transfer（FrET）-based sensor, the entry of cytosolic ATp to the mature chloroplasts of Ar... 详细信息

关键词： ATp translocation and chloroplast biology

Inhibition of NO emission by adding antioxidant mixture in Jatropha biodiesel on the performance and emission characteristics of a C.I. engine

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Frontiers in Energy 2015年第2期9卷 238-245页

作者： A. prABU r. B. ANAND Department of Mechanical Engineering National Institute of Technol-ogy Tiruchirappalli 620015 India

In this paper, the effect of adding an antiox- idant mixture in Jatropha biodiesel as fuel, in a single cylinder, direct injection compression ignition engine was experimentally investigated and the level of pollutants in the exhaust and performance characteristics of the engine were analyzed. Nine test fuels were prepared with three antioxidants, namely, Suecinimide （C4H5NO2）, N,N-dimethyl-p-phenylenediamine-dihydrochloride （C8H14C12N2）, and N-phenyl-p-phenylenediamine （C6H5NHC6H4NH2） added to neat biodiesel at 500 parts per million （ppm）, 1000ppm and 2000ppm and the observed experimental results were compared with those of neat biodiese! and neat diesel as base fuels. The comparison showed that NO emission was reduced drastically for the test fuels with the antioxidant addition of 2000ppm. The maximum reduction of 10% of NO emission was observed for the antioxidant mixture in neat biodiesel, with a slight increase in unburned HC, CO and smoke opacity. In addition, the obtained experimental results reveal that the addition of two antioxidants as mixture in neat biodiesel caused improved NO emission reduction for all test fuels.

关键词： NO emission antioxidants Succinimide,N,N-dimethyl-p-phenylenediamine-dihydrochloride N-phenyl-p-phenylenediamine

Size Dependent physical properties of Nanostructured α-Fe_2O_3 Thin Films Grown by Successive Ionic Layer Adsorption and reaction Method for Antibacterial Application

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Journal of Materials Science & Technology 2015年第1期31卷 1-9页

作者： A.U.Ubale M.r.Belkhedkar Nanostructured Thin Film Materials Laboratory Department of PhysicsGovt.Vidarbha Institute of Science and Humanities Department of physics Shri Shivaji College

Thin films of nanostructured α-FeOwith thickness of 1 56,203 and 251 nm were deposited by successive ionic layer adsorption and reaction(SILAr) method onto glass substrates using FeCl-6HO and NaOH as cationic and anionic *** X-ray diffraction studies revealed that,α-FeOthin films are nanocrystalline in nature with rhombohedral *** morphological properties were investigated by field emission scanning electron and atomic force *** optical studies showed that α-FeOexhibits direct as well as indirect optical band gap *** electrical resistivity of α-FeOat 305 K decreases from 11.76×102 to9.46 × 10~2 Ω cm as film thickness increases from 156 to 251 *** thermo-emf measurements confirmed that α-FeOexhibits n-type *** nanocrystalline α-FeOexhibits antibacterial character against Staphylococcus aureus and its efficiency increases from 37.50%to 87.50%depending on crystallite size.

关键词： Thin films Nanostructures AFM(atomic force microsc

A UNIVErSAL IN TAILING WAVETrAIN GENErATION

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Journal of Hydrodynamics 2004年第5期16卷 603-607页

作者： XUZhao-ting SAMUELS.p.Shen QIAOFang-li InstituteofphysicalOceanographyandphysicalOceanographyLaboratory OceanUniversityofChinaQingdao266003China DepartmentofMathematicsScience UniversityofAlbertaEdmontonT6G2G1Canada KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

A universal in tailing wave-train generation of forced soliton generationover topography is found theoretically as the flows are at the resonant points and it is examinedwith the numerical calculation of the corresponding fKdV e-quatioa From the comparisons, it is shownthat theoretical and numerical results on the invariance is in good agreement and the theory givenin this paper does not include the modulus truncation, any free constant and unknown function.

关键词： universal soliton tailing wave-train fKdV equation KdV equations

DATA rEDUCTION OF SNApSHOT VLBI OBSErVATIONS

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Science China Mathematics 1991年第5期34卷 590-597页

作者：南仁东 r.T.SCHILIZZI C. r.FANTI 邓杰 Beijing Astronomical Observatory Academia Sinica Beijing 100080 PRC radiosterrenwacht Dwingeloo the Netherlands Dipartimento di Astronomia Universita di BolognaItaly

Data reduction techniques have been developed for generating images of radio sourcesfrom snapshot very long baseline interferometry (VLBI) observations with poor u-v *** reliability of the radio source structures is d... 详细信息

关键词： VLBI CSS snapshot observation.

Outage performance of Cognitive DF relaying Networks Employing SWIpT

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China Communications 2018年第4期15卷 28-40页

作者： Jing Yang Yiyun Cheng Kostas p. peppas p. Takis Mathiopoulos Jie Ding School of Information Engineering Yangzhou University Yangzhou 225009 China Department of Telecommunication Science and Technology University of Peloponnese Tripoli 22100 Greece Department of lnformatics and Telecommunications National and Kapodistrian University of Athens Athens 157 84 Greece

In this paper, the outage perfor- mance of a cognitive relaying network over Nakagami-m fading channels, employing simultaneous wireless information and power transfer （SWIpT） technology is analyzed and evaluated. The operation of this network is considered in conjunction with the convention- al decode-and-forward （DF） and incremental DF （IDF） protocols. For the conventional DF protocol, it is assumed that there is no direct link between the secondary transmitter （S） and the secondary destination （D）, while （for both protocols） after harvesting energy, the relay node （r） always helps to forward the resulting signal to D. However, for the IDF protocol, r assists in relaying S＇s information to D only when the direct communication between S and D has failed. Furthermore, for both DF and IDF protocols, we assume there is no power supply for r, and r harvests energy from the transmitted signal of S. We derive exact ana- lytical expressions for the outage probability at D in DF and IDF protocols, respectively, in terms of the bivariate Meijer＇s G-function. performance evaluation results obtained by means of Monte-Carlo simulations are also provided and have validated the correctness of the oroDosed analysis.

关键词： cognitive relaying networks out-age probability energy harvestin incrementaldecode-and-forward

prognosis of residual coal gas capacity made by the ‘Express' method

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International Journal of Minerals,Metallurgy and Materials 2011年第2期18卷 127-131页

作者： pavel prokop pavel Zapletal Ivo pěgímek Technical University of Ostrava

An easy, reliable, and inexpensive method, called ＇Express＇ method, was described to determine the residual gas capacity of deep mines using results from an air and gas balance. Air and gas balances are common elements of mine management and must be performed periodically. Using the process described here to obtain balance results, it is straightforward to obtain the residual gas capacity, which is an important parameter for decision-making in current mine operations. After a mine is closed, the residual gas capacity becomes a dominant factor used to select methods to protect against gas emissions from the closed underground area or perhaps to provide information for the use of gas reserves. The proposed ＇Express＇ method is a much simpler method to obtain the residual gas capacity than other procedures used for this purpose to date.

关键词： coal mines gas storage methane ventilation degassing

Effect of induced magnetic field on natural convection in vertical concentric annuli

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Acta Mechanica Sinica 2012年第2期28卷 315-323页

作者： r.K.Singh A.K.Singh Department of Mathematics Central University of BiharPatnaIndia Department of Mathematics Banaras Hindu UniversityVaranasiIndia

In the present paper, we have considered the steady fully developed laminar natural convective flow in open ended vertical concentric annuli in the presence of a ra- dial magnetic field. The induced magnetic field produced by the motion of an electrically conducting fluid is taken into account. The transport equations concerned with the con- sidered model are first recast in the non-dimensional form and then unified analytical solutions for the velocity, induced magnetic field and temperature field are obtained for the cases of isothermal and constant heat flux on the inner cylin- der of concentric annuli. The effects of the various phys- ical parameters appearing into the model are demonstrated through graphs and tables. It is found that the magnitude of maximum value of the fluid velocity as well as induced magnetic field is greater in the case of isothermal condition compared with the constant heat flux case when the gap be- tween the cylinders is less or equal to 1.70 times the radius of inner cylinder, while reverse trend occurs when the gap between the cylinders is greater than 1.71 times the radius of inner cylinder. These fields are almost the same when the gap between the cylinders is equal to 1.71 times the radius of inner cylinder for both the cases. It is also found that as the Hartmann number increases, there is a flattening ten- dency for both the velocity and the induced magnetic field. The influence of the induced magnetic field is to increase the velocity profiles.

关键词： Natural convection Isothermal Heat flux Skin-friction Induced magnetic field Magnetohydrody- namics