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Aboveground nutrient components of Eucalyptus camaldulensis and E. grandis in semiarid Brazil under the nature and the mycorrhizal inoculation conditions

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Journal of Forestry research 2009年第1期20卷 15-22页

作者： Marcela C. Pagano Antonio F. Bellote Maria r. Scotti Microorganism-Plant Interaction LaboratolT Institute of Biological Sciences Federal University of Minas Gerais Av. Antonio Carlos 6627 Pampulha CEP： 31270-901 Belo Horizonte MG Brazil Embrapa Forestry Estrada da Ribeira km 111 Caixa Postal 319 - Colombo PR - 83411-000- Brazil.

A study was conducted to evaluate the aboveground biomass, nutrient content and the percentages of mycorrhizal colonization in Eucalyptus camaldulensis and Eucalyptus grand＆ plantations in the semiarid region （ 15° 09′ S 43° 49′ W） in the north of the State of Minas Gerais in Brazil. results show that the total above-ground biomass （dry matter） was 33.6 ***^-1 for E. camaldulensis and 53.1 Mg·ha^-1 for E. grandis. The biomass of the stem wood, leaves, branches, and stein bark for E. camaldulens accounted for 64.4%, 19.6%, 15.4%, and 0.6% of the total biomass, respectively （Table 2）; meanwhile a similar partition of the total above-ground biomass was also found for E. grand＆. The dry matter of leaves and branches of E. camaldulensis accounted for 35% of total biomass, and the contents of N, P, K, Ca, Mg, and S in leaves and branches accounted for 15.5%, 0.7%, 12.3%, 22.6%, 1.9%, and 1.4% of those in total above-ground biomass, respectively. In the trunk （bark and wood）, nutrient accumulation in general was lower. Nutrient content of E. grand＆ presented little variation compared with that orE. camaJd^llensis. Wood localized in superior parts of trunk presented a higher concentration of P and bark contained significant amounts of nutrients, especially in E. grand＆. This indicated that leaving vegetal waste is of importance on the site in reducing the loss of tree productivity in this semi-arid region. The two species showed mycotrophy.

关键词： Eucalyptus biomass nutrient components semi-arid region mycorrhizal symbioses Brazil

A new efficient optimal path planner for mobile robot based on Invasive Weed Optimization algorithm

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Frontiers of Mechanical Engineering 2014年第4期9卷 317-330页

作者： Prases K. MOHANTY Dayal r. PArHI robotics Laboratory National Institute of Technology Rourkela769008 India

Planning of the shortest/optimal route is essential for efficient operation of autonomous mobile robot or vehicle. In this paper Invasive Weed Optimization （IWO）, a new meta-heuristic algorithm, has been imple- mented for solving the path planning problem of mobile robot in partially or totally unknown environments. This meta-heuristic optimization is based on the colonizing property of weeds. First we have framed an objective function that satisfied the conditions of obstacle avoidance and target seeking behavior of robot in partially or completely unknown environments. Depending upon the value of objective function of each weed in colony, the robot avoids obstacles and proceeds towards destination. The optimal trajectory is generated with this navigational algorithm when robot reaches its destination. The effec- tiveness, feasibility, and robustness of the proposed algorithm has been demonstrated through series of simulation and experimental results. Finally, it has been found that the developed path planning algorithm can be effectively applied to any kind of complex situation.

关键词： mobile robot obstacle avoidance InvasiveWeed Optimization navigation

Stability analysis solutions of the nonlinear modified Degasperis-Procesi water wave equation

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Journal of Ocean Engineering and Science 2017年第3期2卷 155-160页

作者： M.A.Helal Aly r.Seadawy M.Zekry Mathematics Department Faculty of ScienceCairo UniversityGizaEgypt Mathematics Department Faculty of ScienceTaibah UniversityAl-UlaSaudi Arabia Mathematics Department Faculty of ScienceBeni-Suef UniversityEgypt

In the present study,the solitary wave solutions of modified Degasperis-Procesi equation are *** the standard Degasperis-Procesi equation,where multi-peakon solutions arise,the modification caused a change in the characteristic of these peakon solutions and changed it to bell-shaped *** using the extended auxiliary equation method,we deduced some new soliton solutions of the fourthorder nonlinear modified Degasperis-Procesi equation with constant *** solutions include symmetrical,non-symmetrical kink solutions,solitary pattern solutions,weiestrass elliptic function solutions and triangular function *** discuss the stability analysis for these solutions.

关键词： Modified Degasperis-Procesi water wave equation Extended auxiliary equation method Solitary wave solutions

LIE IDEALS, MOrITA CONTEXT AND GENErALIZED (α, β)-DErIVATIONS

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Acta Mathematica Scientia 2013年第4期33卷 1059-1070页

作者： S.Khalid NAUMAN Nadeem ur rEHMAN r.M.AL-OMArY Department of Mathematics King Abdulaziz University Department of Mathematics Aligarh Muslim University Department of Mathematics Ibb University

A classical problem in ring theory is to study conditions under which a ring is forced to become commutative. Stimulated from Jacobson＇s famous result, several tech- niques are developed to achieve this goal. In the present note, we use a pair of rings, which are the ingredients of a Morita context, and obtain that if one of the ring is prime with the generalized （α β）-derivations that satisfy certain conditions on the trace ideal of the ring, which by default is a Lie ideal, and the other ring is reduced, then the trace ideal of the reduced ring is contained in the center of the ring. As an outcome, in case of a semi-projective Morita context, the reduced ring becomes commutative.

关键词： prime rings (α β)-derivations and generalized (α β)-derivations Lie ideals Morita context

Optimal Coverage Multi-Path Scheduling Scheme with Multiple Mobile Sinks for WSNs

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Computers, Materials & Continua 2020年第2期62卷 695-711页

作者： Jin Wang Yu Gao Chang Zhou r.Simon Sherratt Lei Wang School of Computer&Communication Engineering Changsha University of Science&TechnologyChangsha410114China School of Information Engineering Yangzhou UniversityYangzhou225009China School of Information Science and Engineering Fujian University of TechnologyFuzhou350000China Department of Biomedical Engineering University of ReadingBerkshire RG66AYUK School of Civil Engineering Changsha University of Science&TechnologyChangsha410114China

Wireless Sensor Networks(WSNs)are usually formed with many tiny sensors which are randomly deployed within sensing field for target *** sensors can transmit their monitored data to the sink in a multi-hop communication ***,the‘hot spots’problem will be caused since nodes near sink will consume more energy during ***,mobile sink based technology provides an alternative solution for the long-distance communication and sensor nodes only need to use single hop communication to the mobile sink during data *** though it is difficult to consider many network metrics such as sensor position,residual energy and coverage rate etc.,it is still very important to schedule a reasonable moving trajectory for the mobile *** this paper,a novel trajectory scheduling method based on coverage rate for multiple mobile sinks(TSCr-M)is presented especially for large-scale *** improved particle swarm optimization(PSO)combined with mutation operator is introduced to search the parking positions with optimal coverage *** the genetic algorithm(GA)is adopted to schedule the moving trajectory for multiple mobile *** simulations are performed to validate the performance of our proposed method.

关键词： WSNs mobile sink trajectory scheduling network performance

Electro-Pulse-Boring(EPB): Novel Super-Deep Drilling Technology for Low Cost Electricity

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Journal of Earth Science 2015年第1期26卷 37-46页

作者： Hans O.Schiegg Arild rdland Guizhi Zhu David A.Yuen SwissG eo Power AG Stadtturmstrasse 19 CH-5401Switzerland Department of Petroleum Engineering and Applied Geophysics Norwegian University of Science and Technology7491 TrondheimNorway Department of Earth Sciences ETH-Zurich CH-8092Switzerland Department of Earth Sciences and Minnesota Supercomputing Institute University of MinnesotaMinneapolis MN 55455USA School of Environmental Studies China University of Geosciences

The inexhaustible heat deposit in great depths （5-10 km） is a scientific fact. Such deposit occurs around the globe. Thereby, everybody is enabled to generate autonomously clean and renewable energy, ample electricity and heat. The economical exploration and exploitation of this superdeep geothermal heat deposit requires a novel drilling technique, because the currently only deep drilling method （rotary） is limited to about 5 km, due to the rising costs, depending exponentially on depth. Electro-pulse-boring （EPB） is a valuable option to rotary drilling. EPB, originally investigated in russia, is ready to be developed for industrialization. The feasibility of EPB is proven by many boreholes drilled up to 200 m in granite （crystalline）. Estimates show outstanding low costs for drilling by EPB： 100 E/m for a borehole with a large diameter （φ） such as 20 （50 cm）, independent on depth and applicable likewise for sediments and crystalline rocks, such as granite. The current rate of penetration （rOP） of 3 m per hour is planned to be augmented up to 35 m per hour, and again, irrespective whether in sedimentary or crystalline formations. Consequently, a 10 km deep borehole with φ 50 cm will ultimately be drilled within 12 days. EPB will create new markets, such as：（i） EPB shallow drilling for geotechnics, energy piles, measures in order to mitigate natural hazards, etc., （ii） EPB deep drilling （3-5 km） for hydro-geothermics, exploration campaigns etc. and （iii） EPB super-deep drilling （5-10 km） for petro-geothermies, enabling the economic generation of electricity. The autonomous and unlimited supply with cost efficient electricity, besides ample heat, ensures reliably clean and renew- able energy, thus, high supply security. Such development will provide a substantial relief to cope with the global challenge to limit the climate change below 2 ℃. The diminution of fossil fuels, due to the energy transition in order to mitigate the climate change, implies likewise the decr

关键词： drilling technology electro pulse petro-geothermics geoenergy geothermal electricity climate change air pollution.

The Mineralisation Process as Deduced from Sr Isotopic Data from Lonplats' Eastern Platinum Mine,Western Bushveld Complex and Large-Scale Geometry of the Floor to the Merensky reef

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地学前缘 2009年第S1期16卷 164-165页

作者： refilwe Shelembe r.Grant Cawthorn Council for Geoscience University of the Witwatersrand

At Eastern Platinum Mine in the western Bushveld Complex,the entire Merensky Pyroxenite Unit reaches up to 11 m in thickness,in contrast to many sections where it is only 1-3 m *** greatly expanded section allows for a more detailed investigation of processes that are normally telescoped to the point of being *** minor platinum-group element(PGE)

关键词： PGE mineralisation pressure increase funnel-shaped magma chamber

Galvanically induced potentials to enable minimal tribochemical wear of stainless steel lubricated with sodium chloride and ionic liquid aqueous solution

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Friction 2018年第2期6卷 230-242页

作者： Tobias AMANN Felix GATTI Natalie OBErLE Andreas KAILEr Jürgen rüHE Fraunhofer Institute for Mechanics of Materials IWM Institute for Macromolecular Chemistry University of Freiburg IMTEK-Department of Microsystems Engineering University of Freiburg

The effect of galvanically induced potentials on the friction and wear behavior of a 1 rK91 stainless steel regarding to tribocorrosion was investigated using an oscillating ball-on-disk tribometer equipped with an electrochemical cell. The aim of this investigation is to develop a water-based lubricant. Therefore 1 molar sodium chloride(NaCl) and 1% 1-ethyl-3-methylimidazolium chloride [C_2 mim][Cl] water solutions were used. Tribological performance at two galvanically induced potentials was compared with the non-polarized state: cathodic potential-coupling with pure aluminum- and anodic potential-coupling with pure copper. Frictional and electrochemical response was recorded during the tests. In addition, wear morphology and chemical composition of the steel were analyzed using scanning electron microscopy(SEM) and X-ray photoelectron spectroscopy(XPS), respectively. The galvanically induced cathodic polarization of the stainless steel surface results in electrochemical corrosion protection and the formation of a tribolayer. Cations from the electrolyte(sodium Na^+ and 1-ethyl- 3-methylimidazolium [C_2 mim]^+) interact and adhere on the surface. These chemical interactions lead to considerably reduced wear using 1 NaC l(86%) and 1% 1-ethyl-3-methylimidazolium chloride [C_2 mim][Cl](74%) compared to the nonpolarized system. In addition, mechanical and corrosive part of wear was identified using this electrochemical technique. Therefore this method describes a promising method to develop water-based lubricants for technical applications.

关键词： sliding wear tribochemistry potential controlled friction and wear galvanic coupling ionic liquids tribolayer formation

Effect of Drainage Ditch Layout on Nitrogen Loss by runoff from an Agricultural Watershed

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Pedosphere 2013年第2期23卷 256-264页

作者： ZHANG Zhan-Yu KONG Li-Li ZHU Lei r.M.MWIYA Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China Ministry of EducationHohai University College of Water Conservancy and Hydropower Engineering Hohai University

A comparison experiment was performed, by designing one field ditch (D1 treatment), two field ditches (D2 treatment), three field ditches (D3 treatment), and no field ditch (CK treatment), in an upland of a small agricultural watershed in Nanjing-Zhenjiang hilly regions to observe the farmland surface runoff and N loss characteristics under the different layouts of field ditch. As the layout density of field ditch increased, the drainage effect was improved, the timing of the runoff peak was advanced, and also the peak flow was augmented. At the same time, both the concentration and accumulated transfer flux of total nitrogen (TN) were improved, and thereinto the accumulated transfer fluxes of TN under D3, D2 and D1 treatments were increased by 1.46, 1.34 and 1.16 times, respectively, than that under CK treatment. However, the accumulated transfer fluxes of nitrate-nitrogen (NO3-N) and ammonium-nitrogen (NH+4 -N) under D3, D2 and D1 treatments were reduced by 33.9%, 21.4% and 8.6%, and 35.8%, 24.7% and 12.2%, respectively, compared with those under CK treatment. Under CK treatment, the NO3-N and NH+4-N concentrations were more sensitive to rainfall intensity than the TN concentration. There were significant linear relationships between the transfer fluxes of TN, NO3 -N and NH+4 -N and the runoff flux, with the correlation coefficients of 0.942, 0.899 and 0.912, respectively. In addition, this correlation was also influenced by the layout density of field ditch. Therefore, the environmental effect should be taken into account when designing and constructing field ditches. Especially in the regions of severe fertilizer loss, the approaches of properly increasing the drainage area and decreasing the layout density of field ditch could be adopted under the precondition of avoiding crops from waterlogging.

关键词：径流流失排水沟渠小流域农业 NO3-N NH4-N 氮素峰值时间