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Effects of Different Types of Sludge on Soil Microbial Properties:A Field Experiment on Degraded Mediterranean Soils

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Pedosphere 2010年第6期20卷 681-691页

作者： D.TARRASóN g.OJEDA O.ORTIZ J.M.ALCAIZ Centre for Ecological Research and Forestry Applications Autonomous University of Barcelona IMAR-Coimbra Interdisciplinary Centre Department of ZoologyUniversity of Coimbra

The recycling of suitable organic wastes can enhance soil fertility via effects on soil physical, chemical and biological properties. To compare the effects of digested (DS), thermally dried (TDS) and composted dewatered (CDS) sewage sludge on soil microbiological properties, an experiment was conducted at field sites for more than one year (401 d) when applied to two Mediterranean degraded soils (loam and loamy sand soils). All three types of sewage sludge had a significant effect on measured parameters. In a short time, the plots of both loamy sand and loam soils amended with TDS showed the highest microbial basal respiration (loam soil: P ghest microbial metabolic quotient (qCO 2 ) (P ge caused transient non-equilibrium effects on almost all soil microbial properties. However, there were no differences one year later because the remaining organic carbon was stable and quite similar in all treatments. These results may have practical implications for the rehabilitation of degraded soils.

关键词： basal respiration composted sludge soil microbial biomass thermally dried sludge

An Efficient Numerical Scheme for Biological Models in the Frame of Bernoulli Wavelets

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2381-2408页

作者： Fei Li Haci Mehmet Baskonus S.Kumbinarasaiah g.Manohara Wei gao Esin Ilhan Department of Scientific Research Yunnan Normal UniversityKunming650500China Department of Mathematics and Science Education Harran UniversitySanliurfa63050Türkiye Department of Mathematics Bangalore UniversityBengaluru560056India School of Information Science and Technology Yunnan Normal UniversityKunming650500China Faculty of Engineering and Architecture Kirsehir Ahi Evran UniversityKırsehir40500Türkiye

This article considers three types of biological systems:the dengue fever disease model,the COVID-19 virus model,and the transmission of Tuberculosis *** new technique of creating the integration matrix for the Bernoulli wavelets is ***,the novel method proposed in this paper is called the Bernoulli wavelet collocation scheme(BWCM).All three models are in the form system of coupled ordinary differential equations without an exact *** systems are converted into a system of algebraic equations using the Bernoulli wavelet collocation *** numerical wave distributions of these governing models are obtained by solving the algebraic equations via the Newton-Raphson *** results obtained from the developed strategy are compared to several schemes such as the Runge Kutta method,and ND solver in mathematical *** convergence analyses are discussed through *** newly implemented Bernoulli wavelet method improves the accuracy and converges when it is compared with the existing methods in the literature.

关键词： Biological systems system of coupled ODEs bernoulli wavelets functional matrix collocation technique

Using SPOT 5 fusion-ready imagery to detect Chinese tamarisk(saltcedar)with mathematical morphological method

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International Journal of Digital Earth 2014年第3期7卷 217-228页

作者： Q.S.Liu g.H.Liu C.Huang C.J.Xie State Key Laboratory of Resources and Environmental Information System Institute of Geographic Science and Natural Resources ResearchChinese Academy of SciencesBeijingChina

Chinese tamarisk(saltcedar)is a deciduous shrub that occurs widely across the Yellow River Delta in *** spatial structure of Chinese tamarisk is believed to have an influence on the landscape and habitats of rare *** this study,first,Chinese tamarisk is detected using Canny edge detector and mathematical morphological operators based on SPOT 5 fusion-ready *** the numbers,areas,locations,and patch spacing of Chinese tamarisk patches are *** experiments show that the detection accuracy of Chinese tamarisk patches is about 93.4%after the disconnection of connected *** distribution orientation of about 70%of the patches is approximately *** 91%of the minimum distances among the patches are between 12.5 and 57.5 *** rose graph indicates that the main azimuth between patches is north--northwest,and the second is northeast and *** present study indicates that the integrating Canny edge detector with the algorithms for extracting circular and elliptical objects based on mathematical morphology is simple and effective for detecting Chinese tamarisk patches and is easy to identify the spatial structure of Chinese tamarisk patches,which reduces the time and labor for the visual interpretation of Chinese tamarisk patches.

关键词： SPOT 5 Chinese tamarisk spatial structure mathematical morphology patch

Mechanical Behaviour and Structure Instability of Al_3Ti Alloy

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Journal of Materials Science & Technology 1994年第1期10卷 1-14页

作者： D.g.Morris(Institute of Structural Metallurgy, University of Neuchatel, Avenue de Bellevaux 51, Neuchatel, Switzerland) Univ of Neuchatel Neuchatel Switzerland

Trialuminide alloys of elements such as Ti. Nb or Zr are of particular interest as materials for high temperature usage because their density is very low and specific strength and elastic rnoduli are then very high. This report concentrates on recent work on Al3Ti alloys which have been alloyed with ternary elements such that the higher symmetry ordered cubic structure is obtained, leading to somewhat easier operation of deformation mechan isms and hence improved ductility and *** details of the crystal structure of cubic trialuminides are considered here and it is shown that the materials generally possess some remnant tetragonal chemical ordering which can affect their me chanical behaviour. In addition the compositional range over which a stable single phase is retained is shown to be extremely small, such that in most cases the materials examined show some form of microstructural instability. These instabilities affect the mechanical behaviour of the materials, for exarnple producing general strengthening. leading to precipitation hardening du ring hig h temperature testing, and causing age hardening instabilities during high temperature static or dynamic *** structural instabifity feads to significant modifications at superdislocations, affecting both the dislocation cores and their associated APB's. Failure for these cubic materials still occurs at very small plastic strains and seems to be determined by difficulties of superdislocation creation near a propagating crack rather than by problems of suitable dislocation configuration and mobility. Possible ways to enhance ductility and toughness by alloying and microstructural modification will be discussed.

关键词： Ti Figure Mechanical Behaviour and Structure Instability of Al3Ti Alloy Al

Clustering of Pathogen-Response genes in the genome of Arabidopsis thaliana

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Journal of Integrative Plant Biology 2011年第10期53卷 824-834页

作者： Olga A.Postnikova Natalia Y.Minakova Alexander M.Boutanaev Lev g.Nemchinov United States Department of Agriculture Agricultural Research ServicePlant Sciences InstituteMolecular Plant Pathology Laboratory Institute of Basic Biological Problems Russian Academy of Sciences

Previously, we used heterologous expressed sequence tag （EST） mapping to generate a profile of 4 935 pathogen-response genes of Arabidopsis thaliana. In this work, we performed a computer analysis of this profile, revealing 1594 non-homologous clustered genes distributed among all A. thafiana chromosomes, whose co-regulation may be related to host responses to pathogens. To supplement computer data, we arbitrarily selected two clusters and analyzed their expression levels in A. thaliana ecotypes Col-0 and C24 during infection with the yellow strain of Cucumber mosaic virus CMV（Y）. Ecotype Col-0 is susceptible to CMV（Y）, whereas C24 contains the dominant resistance gene RCY1. Upon infection with CMV（Y）, all clustered genes were significantly activated in the resistant ecotype C24. In addition, we demonstrated that posttranslational histone modifications associated with trimethylation of histone H3 lysine 27 are most likely involved in regulation of several cluster genes described in this study. Overall, our experiments indicated that pathogen-response genes in the genome of A. thaliana may be clustered and co-regulated.

关键词： CMV H3K27me3 heterologous EST mapping clustering of defense-related genes.

Analytical and simulation studies for diode and triode ion beam extraction systems

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Chinese Physics C 2012年第4期36卷 344-349页

作者： M. M. Abdelrahman N. I. Basal S. g. Zakhary Accelerators & Ion Sources Department Nuclear Research Center Atomic Energy Authority P.O. Box: 13759 Inchas Atomic Energy Authority

This work is concerned with ion beam dynamics and compares the emittance to aberration ratios of two-and three-electrode extraction systems. The study is conducted with the aid of Version 7 of SIMION 3D ray-tracing software. The beam dependence on various parameters of the extraction systems is studied and the numerical results lead to qualitative conclusions. Ion beam characteristics using diode and triode extraction systems are investigated with the aid of the computer code SIMION 3 D, Version 7.0. The diode （two electrode extraction system） and triode （three- electrode extraction, acceleration-deceleration system） extraction systems are designed and optimized with different geometric parameters of the electrode system, voltage applied to the extraction electrode, and plasma parameters inside the ion source chamber, as well as by the ion beam space charge. This work attempts to describe the importance of the acceleration-deceleration extraction system. It shows that besides an increase of the beam energy, the ion beam has lower emittance than the two-electrode extraction system. Ion beams of the highest quality are extracted whenever the half-angular divergence is minimum for which the perveance current intensity and the extraction gap have optimum value. Knowing the electron temperature of the plasma is necessary to determine plasma potential and the exact beam energy.

关键词： ion beam emittance plasma meniscus space charge ion beam SIMION computer program

Central nucleus-nucleus collisions at relativistic energies with a new method based on Random Matrix Theory

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Chinese Physics C 2010年第8期34卷 1076-1081页

作者： Z.Wazir R.g.Nazmitdinov E.I.Shahaliev M.K.Suleymanov Department of Physics COMSATS Institute of Information Technology Department de Fisica Universitat de les Illes Balears Bogoliubov Laboratory of Theoretical Physics Joint Institute for Nuclear Research High Energy Physics Laboratory Joint Institute for Nuclear Research Institute of Radiation Problems

Using the method based on Random Matrix Theory （RMT）, the results for the nearest-neighbor distributions obtained from the experimental data on ^12C-C collisions at 4.2 AgeV/c have been discussed and compared with the simulated data on ^12C-C collisions at 4.2 AgeV/c produced with the aid of the Dubna Cascade Model. The results show that the correlation of secondary particles decreases with an increasing number of charged particles Nch. These observed changes in the nearest-neighbor distributions of charged particles could be associated with the centrality variation of the collisions.

关键词： random matrix theory experimental data Dubna cascade model central collisions

IMPROVINg THE SURFACE PROPERTY OF TC4 ALLOY BY LASER NITRIDINg AND ITS MECHANISM

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Acta Metallurgica Sinica(English Letters) 2006年第2期19卷 151-156页

作者： Y.L. Yang g.J. Zhao D. Zhang C.S. Liu gollege of Sdence Northeastern University Shenyang 110004 Ghina College of Material and Metallurgy Northeastern University Shenya g 110004 China

The mixing technology of laser and heated nitrogen was applied to improve the surface hardness of titanium alloy （ TC4 ）. The samples were nitrided with laser power density of 6.S × 10^6SW. cm^-2, the scanning speed varioas from 100 to 500mm ·min^-1. The nitrogen gas was pre-heated to 300℃ to accelerate the nitriding process. Some interested samples were tested with XRD method （X-ray diffraction） to analyze the composition of nitrides, and the surface hardness of HV was measured. The results show that TiN and Ti2N were formed on the surface of Ti alloy with proper nitriding parameters, but TiN is the main composition. The surface hardness increased by three times, which is from the original value of 269to 794kg·mm^-2. The mechanism of the mixing technology is considered mainly of the activation of nitrogen by laser power and the pre-heated process which accelerated the nitriding process. The nitridation process can be considered as six steps given in detail. The result by analyzing the mechanism of improving the surface property of TiAl alloy shows the improvement of surface property due to two factors： the first reason is the result of laser annealing, and the second one is the formation of TiN.

关键词： laser nitridation surface property Ti alloy

gRAIN-BOUNDARY PRECIPITATION UNDER IRRADIATION IN DILUTE BINARY ALLOYS

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Acta Metallurgica Sinica(English Letters) 2003年第5期16卷 365-374页

作者： S.H.Song Z.X.Yuan J.Liu R.g.Faulkner SchoolofMaterialsandMetallurgy WuhanUniversityofScienceandTechnologyWuhan430081China InstituteofPolymerTechnologyandMaterialsEngineering LoughboroughUniversityLoughboroughLe-icestershireLE113TUUK

Irradiation-induced grain boundary segregation of solute atoms frequently bring about grain boundary precipitation of a second phase because of its making the solubility limit of the solute surpassed at grain boundaries. Until now the kinetic models for irradiation-induced grain boundary precipitation have been sparse. For this reason, we have theoretically treated grain boundary precipitation under irradiation in dilute binary alloys. Predictions of γ' -Ni3Si precipitation at grain boundaries are made for a dilute Ni-Si alloy subjected to irradiation. It is demonstrated that grain boundary silicon segregation under irradiation may lead to grain boundary γ'-Ni3Si precipitation over a certain temperature range.

关键词： segregation precipitation grain boundary irradiation