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Influence of Fly Ash and Sewage Sludge Application on cadmium and Lead Sorption by an Acidic Alfisol

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Pedosphere 2010年第4期20卷 436-445页

作者： S.m.SHAHEEN c.D.TSADILAS Department of Soil Sciences Faculty of AgricultureUniversity of Kafrelsheikh National Agricultural Research Foundation Institute of Soil Mapping and Classification(Greece)

The safe recycling of fly ash (FA) and sewage sludge (SS) in the agricultural processes comprises an important environmental technology on waste management. Soils amended with FA and SS may change their ability to adsorb heavy metals due to either increase of soil pH or decomposition of sludge-borne organic matter. Thus, cd and Pb sorption was investigated by 1-month incubation under soil moisture content at field capacity and room temperature with an acidic Typic Haploxeroalf from central Greece amended with varying amounts of FA and SS. Batch experiments were conducted by equilibrating the soil samples with cacl2 solutions containing 0-400 mg Pb L-1 or 0-100 mg cd L-1. The results showed that the Freundlich equation described well the cd and Pb sorption. Distribution coefficient (Kd) values of Pb were higher than those of cd in all the treatments of this study. Application of FA increased Kd values for cd and Pb to 8.2 and 2.3 times more than the controls, respectively. Simultaneous applications of FA and SS caused a Kd increase of 3.8 and 2.1 times compared to the treatments that received only SS for cd and Pb, respectively. Treatment of SS alone did not significantly change cd and Pb sorption compared to the controls. The sorption reactions seemed to be mainly affected by soil pH, which was revealed by the significant correlations of cd and Pb sorption with soil pH. These suggested that fly ash was very useful as a low-cost adsorbent for cd and Pb and could be used as an ameliorant for biosolid-amended acidic soils.

关键词： ameliorant distribution coefficient Freundlich equation heavy metals soil pH

magnetism,optical,and thermoelectric response of cdFe_2O_4by using DFT scheme

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chinese Physics B 2018年第3期27卷 376-383页

作者： Q mahmood m Yaseen K c Bhamu Asif mahmood Y Javed Shahid m Ramay materials Growth and Simulation Laboratory Department of PhysicsUniversity of the Punjab Department of Physics University of AgricultureFaisalabad Department of Physics Goa University chemical Engineering Department College of Engineering King Saud University Physics and Astronomy Department College of Science King Saud University

comparative analysis of electronic, magnetic, optical, and thermoelectric properties of cdFe2O4, calculated by em- ploying PBEsol ＋ mBJ has been done. The PBEsol reveals metallic nature, while TB-mBJ illustrates ferromagnetic semiconducting behavior. The reasons behind the origin of ferromagnetism are explored by observing the exchange, crystal field, and John-Teller energies. The optical nature is investigated by analyzing dielectric constants, refraction, absorption coefficient, reflectivity, and optical conductivity. Finally, thermoelectric properties are elaborated by describing the electri- cal and thermal conductivities, Seebeck coefficient, and power factor. The strong absorption for the visible energy and high power factor suggest cdFe2O4 as the potential candidate for renewable energy applications.

关键词： frustrated magnetism density functional theory John-Teller distortion Hund's rule

Non-axisymmetric Homann stagnation-point flow of Walter’s B nanofluid over a cylindrical disk

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Applied mathematics and mechanics(English Edition) 2020年第5期41卷 725-740页

作者： m.KHAN m.SARFRAZ J.AHmED L.AHmAD c.FETEcAU Department of mathematics Quaid-i-Azam UniversityTaxila 47050Pakistan Department of Basic Sciences University of Engineering and TechnologySheringal Upper Dir 18000Pakistan Department of mathematics Shaheed Benazir Bhutto UniversitySheringal Upper Dir 18000Pakistan Academy of Romanian Scientists Bucuresti 050094Romania

The study of non-axisymmetric Homann stagnation-point flow of Walter’s B nanofluid along with magnetohydrodynamic(mHD) and non-linear Rosseland thermal radiation over a cylindrical disk in the existence of the time-independent free stream is considered. moreover, the notable impacts of thermophoresis and Brownian motion are analyzed by Buongiorno’s model. The momentum, energy, and concentration equations are converted into the dimensionless coupled ordinary differential equations via similarity transformations, which are later numerically solved by altering the values of the pertinent parameters. The numerical and asymptotic solutions for the large shear-to-strain rate ratio γ =a/bfor the parameters of the displacement thicknesses and the wall-shear stress are computed by perturbative expansion and analyzed. Furthermore, the technique bvp4c in mATLAB is deployed as an efficient method to analyze the calculations for the non-dimensional velocities, temperature, displacement thickness, and concentration profiles. It is observed that the two-dimensional displacement thickness parameters α andβ are reduced due to the viscoelasticity and magnetic field effects. moreover, when the shear-to-strain rate ratio approaches infinity, α is closer to its asymptotic value, while βand the three-dimensional displacement thickness parameter δ1 show the opposite *** outcomes of the viscoelasticity and the magnetic field on the skin friction are also determined. It is concluded that ■ reaches its asymptotic behavior when the shearto-strain rate ratio approaches infinity. meanwhile, ■ shows different results.

关键词： Walter’s B fluid cylindrical disk nanofluid magnetic field non-linear thermal radiation stagnation-point flow

A minimizing Property of Homographic Solutions

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Acta mathematica Sinica,English Series 2014年第2期30卷 353-360页

作者： Abdalla m.mANSUR Daniel c.OFFIN Department of mathematics and Statistics Queen’s University

In this paper, we prove that the homographic solutions to the rhombus four body prob- lem are the variational minimizers of the Lagrangian action restricted on a holonomically constrained rhombus loop space.

关键词： Nbody problems holonomic systems action functional

The energy identity of mountainous areas:the example of Greece

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Journal of mountain Science 2018年第7期15卷 1429-1445页

作者： Nikolas m.KATSOULAKOS Dimitris c.KALIAmPAKOS National Technical University of Athens Metsovion Interdisciplinary Research Center National Technical University of Athens School of Mining and Metallurgical Engineering

mountainous areas have been long recognized as particularly important for the planet and sustainable mountain development is a global priority. In order to improve the socioeconomic development perspectives of mountain societies, efficient and well-targeted energy strategies should be formed. An important step towards this direction is adequate understanding of local conditions and specific features that affect energy sector. This procedure allows the inclusion of "locality" in energy planning and so, decentralized energy production is facilitated. The present study attempts to determine the particular energy identity of mountainous areas. Greece, which is the second most mountainous country in the EU, has been selected as a case study. Essential features of the mountainous space have been selected, namely altitude, inclination, remoteness, lack of productive activities, old buildings/vernacular architecture, in order to explore their interrelation with the energy sector. Based on literature review and research findings the interaction between mountainous character and energy is outlined. Therefore, a framework of the characteristics of mountain energy identity is composed, which can provide support to the formation of specialized energy policy for mountainous areas. Some of the main findings of the present study include the significantly increased energy loads of mountainous areas, the abundance of renewable energy potential in high – altitude areas, the vulnerability of mountain societies to energy poverty and the difficulties in sitting energy projects in the restricted usable space of mountains. Since the literature regarding mountains and energy is rather poor the present paper aspires to be a step towards highlighting the importance of energy issues for mountain areas and societies. By determining the features of mountain energy identity energy planning in high – altitude areas and so, helping make energy planning more effective, such research works can be par

关键词： Energy demand Renewable energy potential Energy poverty mountain energy policy mountain energy identity

ImPROVING THE mEcHANIcAL PROPERTIES OF cOPPER ALLOYS BY THERmO-mEcHANIcAL PROcESSING

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Acta metallurgica Sinica(English Letters) 2004年第2期17卷 111-117页

作者： m.c.Somani L.P.Karjalainen Department of mechanical Engineering University of Oulu90014 OuluFinlandDepartment of Mechanical EngineeringUniversity of Oulu90014 OuluFinland

Systematic physical simulation of thermo-mechanical processing routes has been ap-plied on a Gleeble 1500 simulator to four copper alloys (mass %) cu-0.57co-0.32Si,cu-0.55cr-0.065P, cu-0.22Zr-0.035Si and cu-1.01Ni-0.43Si aimed at clarifying theinfluences of processing conditions on their final properties, strength and electricalconductivity. Flow curves were determined over wide temperature and strain rateranges. Hardness was used as a measure of the strength level achieved. High hard-ness was obtained as using equal amounts (strains 0.5) of cold deformation beforeand after the precipitation annealing stage. The maximum values achieved for thecu-co-Si, cu-cr-P, cu-Zr-Si and cu-Ni-Si alloys were 190, 165, 178 and 193 HV5,respectively. A thermo-mechanical schedule involving the hot deformation-ageing-colddeformation stages showed even better results for the cu-Zr-Si alloy. consequently,the processing routes were designed based on simulation test results and wires of 5 and2mm in diameters have been successfully processed in the industrial scale.

关键词： copper allys thermo-mechanical processing ageing strength flow stress hardness

AcTPred: Activity Prediction in mobile Social Networks

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Tsinghua Science and Technology 2014年第3期19卷 265-274页

作者： Jibing Gong Jie Tang A.c.m. Fong School of Information Science and Engineering Yanshan University Department of computer Science and Technology Tsinghua University University of Glasgow in Singapore

A current trend for online social networks is to turn *** social networks directly reflect our real social life,and therefore are an important source to analyze and understand the underlying dynamics of human behaviors （activities）.In this paper,we study the problem of activity prediction in mobile social *** present a series of observations in two real mobile social networks and then propose a method,AcTPred,based on a dynamic factor-graph model for modeling and predicting users＇ *** approximate algorithm based on mean fields is presented to efficiently learn the proposed *** deploy a real system to collect users＇ mobility behaviors and validate the proposed method on two collected mobile *** results show that the proposed AcTPred model can achieve better performance than baseline methods.

关键词： social prediction activity prediction user modeling social networks

How can the neutrino interact with the electromagnetic field？

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chinese Physics c 2018年第1期42卷 23-31页

作者： m.Novello c.E.L.Ducap centro Brasileiro de Pesquisas Fisicas (cEAc/cBPF) Rua Dr. Xavier Sigaud 150 CEP 22290-180 Rio de Janeiro Brazil

maxwell electrodynamics in the fixed minkowski space-time background can be described in an equivalent way in a curved Riemannian geometry that depends on the electromagnetic field and that we call the electromagnetic metric（e-metric for short）. After showing such geometric equivalence we investigate the possibility that new processes dependent on the e-metric are allowed. In particular, for very high values of the field, a direct coupling of uncharged particles to the electromagnetic field may appear.

关键词： neutrino electromagnetic field effective metric

THE EFFEcT OF BORON AND cARBON ADDITION ON WELDABILITY OF DS TmS-75 SUPERALLOY

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Acta metallurgica Sinica(English Letters) 2005年第1期18卷 24-32页

作者： m.c. chaturvedi N.L. Richards Department of mechanical and Industrial Engineering University of manitoba Winnipeg Manitoba R3T 5V6 CanadaDepartment of Mechanical and Industrial Engineering University of Manitoba Winnipeg Manitoba R3T 5V6 Canada

Four alloys TmS-75 (Base), Base+B, Base+c and TmD-103 (Base+B+c) with varying levels of B, c were directionally solidified (DS), and their weldability was investigated by bead-on-plate electron beam welding. It was found that cracking occurred in the weld-metal, as well as in the heat affected zone (HAZ). Both γ/γ' and/or γ/carbide eutectic contributed to the weld-metal cracking, and the γ/γ' eutectic was found to be mainly responsible for cracking in HAZ. However, constitutional liquation of carbides seems to have made some contribution also. The B addition had a detrimental effect on HAZ cracking susceptibility, while c addition improved it appreciably even in the presence of B. In addition, no obvious differences were observed in cracking susceptibility of weld-metal in the four alloys. The cracking modes and mechanisms underlying the effect of B and c addition on weldability could be explained on the basis of microstructures of the four alloys.

关键词： Ni-based superalloy low melting point constituents liquation cracking