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Two-Thirds Law of Nitrogen Mineralization Under Undisturbed Soil Conditions:A New Theory

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Pedosphere 2008年第2期18卷 149-153页

作者： g.SENEVIRATNE Institute of Fundamental Studies Hantana Road

It is reported in literature that globally, only about two-thirds of N in nutrient sources is available to plants and microbes in soils under undisturbed conditions. The present study explores this phenomenon and suggests a new theory to explain this. Diffusion of NH4^＋ from microsite sources is considered here and analyzed for a capillary of the soil system. It has been found that 68% of NH4^＋ diffused from the nutrient source is initially preserved in the proximity of the nutrient source, whereas, the remaining 32% is diffused away from the nutrient source and possibly immobilized in the nonexchangeable abiotic pools or lost. The NH4^＋ that has been initially retained near the microsites is gradually released to the mineral pool. Thus, about two-thirds of NH4^＋ released from microsites is available only to plants and microbes in the soil. This is a universal, natural mechanism of nutrient conservation for plant and microbial availabilities. The theory has important implications and applications in recommending N fertilizations in the forms of organic or mineral sources to plants grown across various soil textures, for which further studies are needed. Any deviations from this theory can mainly be attributed to various disturbances to the soil; for example, mechanical disturbances, nutrient leaching, and variations in pH and soil faunal activities. This theory may apply to other elements mineralized in the soils under undisturbed conditions, which must be investigated in future studies.

关键词： diffusion fertilizer immobilization mineralization nitrogen

Book Review on River Planet:Rivers from Deep Time to the Modern Crisis by Martin gibling

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Journal of Palaeogeography 2022年第1期11卷 145-150页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at ArlingtonUSA

***“River Planet”,published in October 2021,is a masterpiece by Martin *** in the UK,Martin gibling,Emeritus Professor,Department of Earth and Environmental Sciences,Dalhousie University,Halifax,Nova Scotia,Canada h... 详细信息

关键词： Canada rivers river

Further Observation on Tin Whisker from Electroplated Sn-Mn Alloy

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稀有金属材料与工程 2012年第S1期41卷 280-282页

作者： Wilcox g D Department of Materials Loughborough UniversityLE11 4EQUK

Tin whiskers from Sn-(0-49 wt%)Mn alloy electroplating on polished mild steel were examined with FEg-SEM with *** raw materials were Hull Cell samples kept in an office ambient with different storage time,up to 240 *** is found that,depending on Mn content and plating microstructure,Sn-Mn alloy shows various types of *** for the whisker forest found previously in Sn-20Mn,there exists another in Sn-(1%-5%)*** latter also has a very short incubation time,less than 4 *** interesting finding is that one type of whiskering with surface cap supports an established model.

关键词： Tin whisker microstructure electroplating

A remarkable decade of learning and sharing knowledge through the Journal of Palaeogeography(JoP)(2014-2024):Reminiscences from an Associate Editor-in-Chief

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Journal of Palaeogeography 2024年第4期13卷 1029-1040页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at ArlingtonArlingtonTX 76019USA

In this editorial,an Associate Editor-in-Chief of the Journal of Palaeogeography(JoP)reminisces his publication experience in JoP during the period 2014-2024.1)During a period of nine years,he contributed eight review articles,three discussions,two replies,one book review,one glossary,and one tribute to the first Editor-in-Chief ***-Zhao *** contributions totaled 534 printed pages.2)His contributions examined 19 different domains,such as landslides,submarine fans,seismites,SSDS,hyperpycnites,rivers,etc.3)His contributions coincided with the formative years of JoP.4)The impact of his articles is evident from the Stats published by *** example,his review article“The Landslide Problem”has reached11,611 Reads and 186 Citations after nine years of publication in 2015.5)In 2023,the CNKI(China National Knowledge Infrastructure)recognized his article“Submarine fans:a critical retrospective(1950-2015)”as the Top-1%most-highly cited publications in the Journal of Palaeogeography published during a 10-year survey period:2012-2022.6)He was inducted as a Founding Member of the International Society of Palaeogeography(ISP)at Changping District of China University of Petroleum(Beijing),Beijing on July 16,2022.7)His JoP editorship during the past 10 years has been the most challenging,inspiring,and rewarding experience of his global scientific journey spanning over six decades(1962-2024).

关键词： Journal of Palaeogeography Associate Editor-in-Chief Editorial Landslides Submarine fans Seismites SSDS Hyperpycnites Zeng-Zhao Feng

Discussion on "Thermomagnetic viscoelastic responses in a functionally graded hollow structure"

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Acta Mechanica Sinica 2012年第3期28卷 911-912页

作者： Ugur güven Department of Mechanical Engineering Yildiz Technical University34349 BesiktasIstanbul-Turkey

Allam and Tantawy [1] presented an analytical solu- tion for stress distribution and perturbations of the magnetic field vector in FgM hollow structures made from viscoelas- tic composite materials .While studying thi... 详细信息

关键词： Discussion on Thermomagnetic viscoelastic responses in a functionally graded hollow structure Maxwell FgM

Remembering Mike Bedford （21.5.1932-24.2.2018）

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Asian Journal of Andrology 2018年第4期20卷 420-424页

作者： Trevor g Cooper Article notes Copyright and License information Disclaimer Correspondence: Dr. Tg Cooper (moc.liamg@grovertc) Received 2018 Apr 7 Accepted 2018 Apr 25.Copyright : © The Author(s)(2018)This is an open access journal and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License which allows others to remix tweak and build upon the work non-commercially as long as appropriate credit is given and the new creations are licensed under the identical terms.<h2 class="head no_bottom_margin" id="idm***title"

John Michael Bedford （Figure 1） studied at Sidney Sussex College, Cambridge University （1952-1958）, and gained his BA （1955） and MA （1958） in Natural Sciences, with postgraduate training in Veterinary Medicine and Surgery （Vet MB 1958）. He had academic appointments as a Fellow at Bristol University （1958-1959）, a scientist with MC Chang at the Worcester Foundation in Shrewsbury, MA, USA （1959-1961）,and studied for a PhD in Physiology with Professor Amoroso at the University of London （1961-1965）. During this time, he was also a lecturer at the Royal Veterinary College （1961-1966） and a teacher at the University of London （1965）.

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Phantom energy accretion onto a black hole in Horava-Lifshitz gravity

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Science China(Physics,Mechanics & Astronomy) 2014年第4期57卷 604-607页

作者： ABBAS g. Department of Mathematics COMSATS Institute of Information TechnologySahiwal-57000 Pakistan

In this Letter,we examine the phantom energy accretion onto a Kehagias-Sfetsos black hole in Horava-Lifshitz *** discuss the accretion process onto the black hole,the equations of phantom flow near the black hole have been *** is found that mass of the black hole decreases because of phantom *** discuss the conditions for critical ***,it has been found that the critical accretion phenomena is possible for different values of *** results for the Schwarzschild black hole can be recovered in the limiting case.

关键词： phantom energy accretion black hole Horava-Lifshitz gravity

Surface chemistry of nanoscale Fe_3O_4 dispersed in magnetic fluids

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Science China Chemistry 2007年第6期50卷 754-758页

作者： Bernd güNTHER Fraunhofer Institut für Fertigungstechnik und Angewandte Materialforschung D-28359 Bremen Germany

The interaction between stabilizers and nanoparticles is one of the important factors to prepare stable magnetic fluids. The magnetic nano-size Fe3O4 core with single domain and the average grain size around 8-12 nm were prepared by chemical precipitation method. The O/Fe molar ratio of the particle surface was measured by X-ray photoelectron spectroscopy (XPS). The heat effects of stabilizers ad- sorption on nanoparticles were measured by solution calorimetry. The excess amount of oxygen was possibly the result of the hydroxygen formed on the surface of the nanoparticles. The heat effects showed that compounds containing carboxyl groups can be adsorbed chemically on magnetite by forming chemical bonds. The other stabilizers involving NH-groups, such as polyethylene-imine, can be adsorbed physically. The exothermic value is about half of the former case.

关键词： nanoscale materials heat effect magnetic fluids surface chemistry

Real-time prediction of projectile penetration to laminates by training machine learning models with finite element solver as the trainer

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Defence Technology（防务技术） 2021年第1期17卷 147-160页

作者： Pushkar Wadagbalkar g.R.Liu Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnatiOH 45219USA

Studies on ballistic penetration to laminates is complicated,but important for design effective protection of *** means of study is expensive and can often be *** simulation has been an excellent supplement,but the computation is *** aim of this thesis was to develop and test an effective tool for real-time prediction of projectile penetrations to laminates by training a neural network and a decision tree regression model.A large number of finite element models were developed;the residual velocities of projectiles from finite element simulations were used as the target data and processed to produce sufficient number of training *** focused on steel 4340tpolyurea laminates with various *** different 3D shapes of the projectiles were modeled and used in the *** trained neural network and decision tree model was tested using independently generated test samples using finite element *** predicted projectile velocity values using the trained machine learning models are then compared with the finite element simulation to verify the effectiveness of the ***,both models were trained using a published experimental data of projectile impacts to predict residual velocity of projectiles for the unseen *** of both the models was evaluated and *** trained with Finite element simulation data samples were found capable to give more accurate predication,compared to the models trained with experimental data,because finite element modeling can generate much larger training set,and thus finite element solvers can serve as an excellent *** study also showed that neural network model performs better with small experimental dataset compared to decision tree regression model.

关键词： Finite element simulations Machine learning Neural networks Impact analysis Protective laminates Projectile Decision tree