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Pedosphere 2008年第3期18卷 378-385页

作者： G.BARTH s.VON TuCHER u.sCHMIDHALTER Chair of Plant Nutrition Technical University MunichD-85350 Freising-Weihenstephan(Germany)

The efficacy of nitrification inhibitors depends on soil properties and environmental conditions. The nitrification inhibitor 3.4-dimethylpyrazole phosphate （DMPP） was investigated in a sandy loam and a loamy soil to study its effectiveness as influenced by inhibitor concentration, application form, and soil matric potential. DMPP was applied with concentrations up to 34.6 mg DMPP kg^-1 soil as solution or as ammonium-sulfate/ammonium-nitrate granules formulated with DMPP. DMPP inhibited the oxidation of ammonium in both soils, but this effect was more pronounced in the sandy loam than in the loamy soil. When applied as solution, increasing DMPP concentrations up to 7 mg DMPP kg^-1 soil had no influence on the inhibition. The effectiveness of DMPP formulated as fertilizer granules was superior to the liquid application of DMPP and NH4^＋, particularly in the loamy soil. Without DMPP, a decline in soil matric potential down to -600 kPa decreased nitrification in both soils, but this effect was more pronounced in the sandy loam than in the loamy soil. DMPP was most effective in the sandy loam particularly under conditions of higher soil moisture, i.e., under conditions favorable for nitrate leaching.

关键词： 3,4-dimethylpyrazole phosphate DMPP fertilizer granules nitrification inhibitor

Generation of a long-term daily gridded precipitation dataset for the rTjsj-upper Indus Basin(uIB)through temporal Reconstruction,Correction I sag&Informed Regionalization-“ReCIR”

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International soil and Water Conservation Research 2021年第3期9卷 445-460页

作者： Asim Jahangir khan Manfred Koch Department of Geohydraulics and Engineering Hydrology University of Kassel34125KasselGermany

This study attempted to generate a long-term(1961-2010)daily gridded precipitation dataset for the upper Indus Basin(uIB)with orographic adjustments so as to generate realistic precipitation estimates,enabling hydrological and water resource investigations that can close the water balance,that is difficult,if not impossible to achieve with the currently available precipitation data products for the *** procedure includes temporal reconstruction of precipitation series at points where data were not recorded prior to the mid-nineties,followed by a regionalization of the precipitation series to a smaller scale across the basin(0.125°x 0.125°),while introducing adjustments for the orographic effect and changes in glacier *** reconstruction process involves interpolation of the precipitation at virtual locations of the current(1995-)dense observational network,followed by corrections for frequency and intensity and adjustments for temporal trends at these virtual *** data generated in this way were further validated for temporal and spatial representativeness through evaluation of sWAT-modelled streamflow responses against observed flows across the *** results show that the calibrated sWAT-simulated daily discharge at the basin outlet as well as at different sub-basin outlets,when forcing the model with the reconstructed precipitation of years 1973—1996,is almost identical to that when forcing it with the reference precipitation data(1997-2008).Finally,the spatial distribution pattern of the reconstructed(1961—1996)and reference(1997—2008)precipitation were also found consistent across the uIB,reflecting well the large-scale atmospheric-circulation pattern in the region.

关键词： Precipitation Temporal reconstruction Orographic correction factor(OCF) soil and water assessment tool(sWAT) Glacier/water mass balance upper indus basin(uIB)

Future u.s.-Russian Relations

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Contemporary International Relations 2008年第2期18卷 69-81页

作者： Wei Zonglei research fellow and Deputy Director of the Center for u.s.-European studies,CICIR. the Center for u.s.-European

Presidential changes in Russia and the *** open new opportunities for improving increasingly important bilateral relations,but expectations are not *** the elapse of the so-called Putin autocracy and the Bush unilateralism,u.s.-Russian relations are overshadowed by a new'Cold Word War,'if not a Cold *** *** continue to accuse Russia of running an autocracy in order to justify its own invasive foreign conduct and gain the moral *** two powers will be involved in a bitter struggle,alternating between offensives and defensives, containment and cooperation.

关键词：美国俄罗斯国际关系外交策略

Drilling study on lightweight structural Mg/siC composite for defence applications

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Defence Technology（防务技术） 2019年第4期15卷 557-564页

作者： K. Balamurugan M. uthayakumar s. Thirumalai Kumaran G.s. samy u.T.s. Pillai Department of Mechanical Engineering VFSTR (Deemed to be University) Guntur 522213 India Faculty of Mechanical Engineering Kalasalingam University Krishnankoil 626126 Tamil Nadu India CsIR-NIIsT Material Science and Technology Division Thiruvananthapuram 695019 India

Heat energy generated during machining has been found to have a greater influence on determining the machinability of the *** this work,magnesium-based silicon carbide composite,which has been identified as a suitable lightweight application material,is prepared with the weight ratio of 90:10 by a stir casting *** available Hss drill tools with different diameters of 4,6 and 8 mm are used to perform the drilling operations with governing parameters of spindle speed,feed rate and constant depth of *** image camera of the FLIR E60 series is used to measure the temperature variation in the cutting zone at different operating *** influences of machining temperature on chip morphology,tool wear and surface profile of the machined samples are *** speed has been found to have a significant effect on machining *** spindle speed increases,the diameter of drill tool increases the tool wear and surface profile,*** abrasion and adhesive type of wears are observed in the drill ***,change from abrasion to adhesive wear is noticed with the increase of the diameter of the drill *** plots are drawn with respect to the interaction of governing parameters along with the working temperatures obtained under different machining conditions.

关键词： Magnesium siC Drilling Thermal effect Chip morphology Tool wear

Control strategies of avian influenza pandemic model with time delay

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International Journal of Biomathematics 2017年第7期10卷 219-236页

作者： u. Roman Z. Gul I. saeed u. Hakeem s. shafie Department of Mathematics Bacha Khan University Charsadda Khyber Pakhtunkhwa Pakistan Department of Mathematics University of Malakand Chakdara Dir(Lower) Khyber Pakhtunkhwa Pakistan Department of Mathematics Abdul Wali Khan University Mardan Khyber Pakhtunkhwa Pakistan Department of Mathematical sciences universiti Teknologi Johor Bahru Malaysia

A mathematical model for avian influenza with optimal control strategies is presented as a system of discrete time delay differential equations （DDEs） and its important math-ematical features are analyzed. In alignment to manage this, we develop an optimally controlled pandemic model of avian influenza and insert a time delay with exponential factor. Then we apply two controlled functions in the form of biosecurity of poultry and the education campaign against avian influenza to control the disperse of the dis- ease. Our optimal control strategies will minimize the number of contaminated humans and contaminated birds. We also derive the basic reproduction number to examine the dynamical behavior of the model and demonstrate the existence of the controlled system. For the justification of Our work, we present numerical simulations.

关键词： Time-delay optimal control existence numerical simulation

Dissolution kinetics of iron oxides in clay in oxalic acid solutions

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1083-1087页

作者： u.K. sultana A.s.W. Kurny Department of Materials and Metallurgical Engineering Bangladesh University of Engineering and Technology

Clay samples containing 8.15% iron oxides and 27.49% alumina were leached in oxalic acid. Leaching experiments were per-formed in aqueous solutions of oxalic acid of 0.2-2 mol/L at 40-80 C for up to 90 min. The mixed kinetic mechanism, i.e., t/τ=[（1 2X/3）（1 X）2/3 ]＋b[ 1 （1 X）1/3], seemed to be the most appropriate one to fit the kinetic data of leaching iron oxides contained in clay in the aqueous oxalic acid solutions. The Arrhenius activation energy for leaching in the 1.8 mol/L oxalic acid was found to be 41.035 kJ/mol.

关键词： clay iron oxides leaching oxalic acid kinetics activation energy

Advanced Persistent Threat Detection and Mitigation using Machine Learning Model

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Intelligent Automation & soft Computing 2023年第6期36卷 3691-3707页

作者： u.sakthivelu C.N.s.Vinoth Kumar Department of Networking and Communications College of Engineering and Technology(CET)SRM Institute of Science and TechnologyKattankulathurChennai603203India

The detection of cyber threats has recently been a crucial research domain as the internet and data drive people’s *** cyber-attacks lead to the compromise of data *** proposed system offers complete data protection from Advanced Persistent Threat(APT)attacks with attack detection and defence *** modified lateral movement detection algorithm detects the APT attacks,while the defence is achieved by the Dynamic Deception system that makes use of the belief update *** termination,every cyber-attack undergoes multiple stages,with the most prominent stage being Lateral Movement(LM).The LM uses a Remote Desktop protocol(RDP)technique to authenticate the unauthorised host leaving footprints on the network and host *** anomaly-based approach leveraging the RDP event logs on Windows is used for detecting the evidence of *** extracting various feature sets from the logs,the RDP sessions are classified using machine-learning techniques with high recall and *** is found that the AdaBoost classifier offers better accuracy,precision,F1 score and recall recording 99.9%,99.9%,0.99 and 0.98%.Further,a dynamic deception process is used as a defence mechanism to mitigateAPTattacks.A hybrid encryption communication,dynamic(Internet Protocol)IP address generation,timing selection and policy allocation are established based on mathematical models.A belief update algorithm controls the defender’s *** performance of the proposed system is compared with the state-of-the-art models.

关键词： Advanced persistent threats lateral movement detection dynamic deception remote desktop protocol Internet Protocol attack detection

Dynamics of the phase-change material GeTe across the structural phase transition

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Frontiers of physics 2019年第2期14卷 65-71页

作者： T. Chatterji s. Rols u. D. Wdowik Institut Laue-Langevin 71 avenue des Martyres38000 GrenobleFrance Institut of Technology Pedagogical UniversityPodchorazych 2PL-30-084 KrakowPoland

Results of inelastic neutron scattering experinients and ab initio molecular dynamics simulations for GeTe 一 the parent compound of phase-change materials are reported. The inelastic neutron spectra of GeTe powder samples have been determined in the temperature range extending from 300 to 700 K. The phonon peaks undergo thermal shifts resulting from anharmonic effects being weaker for acoustic than optic modes. A small concentration of free charge carries arising from the presence of Ge-vacancies was found not to affect significantly the neutron weighted phonon densities of states of GeTe. The spectral pattern changes qualitatively across the structural phase transition, but the local structure of GeTe remains hardly affected, as confirmed by the analysis of temperature dependence of the pairdistribution function obtained from ab initio molecular dynamics investigations. The present theoretical studies support in a wide extent our experimental observations and also those provided by local probe methods.

关键词： phase-change mat erials inelastic neutron scattering ab initio molecular dynamics

MODELING A sOLID BOuNDARY As A FLuID OF INFINITE VIsCOsITY

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Chinese Journal of Mechanical Engineering 2000年第1期13卷 2-9页

作者： Gingold Harry Gera Dinesh West Virginia university u. s. A West Virginia university 美国

A new approach to model viscosity in the conservation of momentum equations is presented and discussed. Coefficient of viscosity is modeled in such a way that it reaches asymptotically to infinity at the solid boundary but still yields a finite value for the shear stress at the solid wall. Basic objective of this research is to show that certain combinations of higher order normal velocity gradients become zero at the solid boundary. Malled solutions for the Couette flow and Poiseuille flow between two parallel plates are obtained by modeling the coefficient of viscosity in a novel way. Also, viscous drag computed by our model is expected to yield higher values than the values predicted by the existing models, which matches closely to the experimental data.

关键词： Coefficient of viscosity solid boundary Viscous drag

Viscoelastic and Thermal Properties of Polyurethane Foams Obtained from Renewable and Recyclable Components

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Journal of Renewable Materials 2018年第7期6卷 755-763页

作者： s.Gaidukovs G.Gaidukova A.Ivdre u.Cabulis Faculty of Material science and Applied Chemistry Institute of Polymer MaterialsRiga Technical University3/7 Paula Valdena St.LV 1048RigaLatvia Faculty of Material science and Applied Chemistry Institute of Applied ChemistryRiga Technical University3/7 Paula Valdena St.LV 1048RigaLatvia Latvian state Institute of Wood Chemistry 27 Dzerbenes St.LV-1006RigaLatvia

This article deals with the study of the viscoelastic and thermal properties of polyurethane (Pu) rigid foamsfrom biobased and recycled components. Rapeseed oil (RO) and recycled poly(ethylene terephthalate)(PET) were used to synthesize Pu polyols. Addition of adipic acid (ADA) to polyol resulted in improvedthermal and viscoelastic properties of foam materials. ADA content was varied from 1 to 6 wt%. Results ofthe dynamic mechanical spectra indicate an increase of the storage modulus E′ and the loss modulus E″ inthe whole temperature range for specimens with higher loading of ADA. In addition, damping factor shiftedto higher temperatures, but damping intensity remained almost unaffected by the compositions. scanningelectron microscopy of the foams’ cross sections testified that the average cells’ size of 110 mm was unaffectedby the ADA content in polyol.

关键词： Polyurethane rigid foam rapeseed oil recycled poly(ethylene terephthalate) viscoelastic properties thermalproperties