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Aspect of the specialty metals potentials of pegmatites in western Oban massif,Se Nigeria:A preliminary geochemical approach

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Chinese Journal Of Geochemistry 2012年第4期31卷 355-361页

作者： Oden m.I. Igonor e.e. Department of Geology University of CalabarP.M.B.1115 CalabarNigeria Petra Prospectors Limited Nigeria

minerals in general and rare-metals in particular are of invaluable importance in the development and industrialization of any *** is true as they could affect a nation's national income,employment ratio,Gross National Product,and its entire *** study area(western Oban massif-Se Nigeria) was investigated for its specialty metals bearing potentials because of(1) its geology,which is similar to other specialty metals bearing areas of the world;(2) past works,which points to the area as a likely source of economic deposit of such metals;and(3) the soaring cost of these rare metals in the light of recent upsurge in global information/telecommunication *** from the study,show that only cesium(Cs) and beryllium(Be) show minute signs or indications of enrichment if properly *** these metals should be studied in details to ascertain their economic *** rocks are too deficient in the other rare-metals(lithium,zirconium,strontium,tantalite,niobium,tungsten,gallium,and chromium) to warrant further analysis.

关键词：特种金属尼日利亚地球化学方法电位伟晶岩稀有金属矿地块国民生产总值

Short-time Asymptotics of the Heat Kernel on Bounded Domain with Piecewise Smooth Boundary Conditions and Its Applications to an Ideal Gas

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Acta mathematicae Applicatae Sinica 2004年第2期20卷 215-230页

作者： e.m.e.ZAYeD mathematics Department Faculty of ScienceZagazig UniversityZagazigEgypt

The asymptotic expansion of the heat kernel Θ(t)=sum from ∞ to j=1 exp(-tλ_j) where {λ_j}_(j=1)~∞ are the eigen-values of the negative Laplacian -Δ_n=-sum from n to k=1((?))~2 in R^n(n=2 or 3) is studied for short-time t for a generalbounded domain Ω with a smooth boundary (?)Ω.In this paper,we consider the case of a finite number of theDirichlet conditions φ=0 on Γ_i (i=1,...,J) and the Neumann conditions (?)=0 on Γ_i (i=J+1,...,k) andthe Robin conditions ((?)+γ_i)φ=0 on Γ_i (i=k+1,...,m) where γ_i are piecewise smooth positive impedancefunctions,such that (?)Ω consists of a finite number of piecewise smooth components Γ_i(i=1,...,m) where(?)Ω=(?)Γ_*** construct the required asymptotics in the form of a power series over *** senior coefficients inthis series are specified as functionals of the geometric shape of the domain Ω.This result is applied to calculatethe one-particle partition function of a“special ideal gas”,i.e.,the set of non-interacting particles set up in abox with Dirichlet,Neumann and Robin boundary conditions for the appropriate wave *** the thermodynamic quantities for the ideal gas such as the internal energy,pressure and specific heat revealsthat these quantities alone are incapable of distinguishing between two different shapes of the *** seems to be intuitively clear because it is based on a limited information given by a one-particlepartition function;nevertheless,its formal theoretical motivation is of some interest.

关键词： Inverse problem heat kernel eigenvalues short-time asymptotics special ideal gas one-particle partition function

Remaining Phosphorus estimate Through multiple Regression Analysis

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Pedosphere 2006年第5期16卷 566-571页

作者： m.e.ALVeS A.LAVOReNTI Departamento de Ciencias exatas Escola Superior de Agriculture‘Luiz de Queiroz’-ESALQ/USPPiracicaba (SP) 13418-900 (Brazil)

The remaining phosphorus (Prem), P concentration that remains in solution after shaking soil with 0.01 mol L-1 CaCl2 containing 60μg mL-1 P, is a very useful index for studies related to the chemistry of variable charge soils. Although the Prem determination is a simple procedure, the possibility of estimating accurate values of this index from easily and/or routinely determined soil properties can be very useful for practical purposes. The present research evaluated the Prem estimation through multiple regression analysis in which routinely determined soil chemical data, soil clay content and soil pH measured in 1 mol L-1 NaF (pHNaF) figured as Prem predictor variables. The Prem can be estimated with acceptable accuracy using the above-mentioned approach, and pHNaF not only substitutes for clay content as a predictor variable but also confers more accuracy to the Prem estimates.

关键词： anionic adsorption pHNaF pedotransfer functions tropical soils

Spinless particles in the field of unequal scalar vector Yukawa potentials

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Chinese Physics B 2013年第4期22卷 81-86页

作者： m.Hamzavi S.m.Ikhdair K.e.Thylwe Department of Science and engineering Abhar Branch Islamic Azad University Abhar Iran Department of electrical and electronic engineering Near East University 922022 Nicosia North Cyprus Mersin 10 Turkey Department of Physics Faculty of Science An-Najah National University Nablus West Bank Palestine KTH-mechanics Royal Institute of Technology S-100 44 Stockholm Sweden

We present analytical bound state solutions of the spin-zero Klein–Gordon （KG） particles in the field of unequal mix-ture of scalar and vector Yukawa potentials within the framework of the approximation scheme to the centrifugal potential term for any arbitrary l-state. The approximate energy eigenvalues and unnormalized wave functions are obtained in closed forms using a simple shortcut of the Nikiforov–Uvarov （NU） method. Further, we solve the KG–Yukawa problem for its exact numerical energy eigenvalues via the amplitude phase （AP） method to test the accuracy of the present solutions found by using the NU method. Our numerical tests using energy calculations demonstrate the existence of inter-dimensional degeneracy amongst the energy states of the KG–Yukawa problem. The dependence of the energy on the dimension D is numerically discussed for spatial dimensions D = 2–6.

关键词： Klein–Gordon equation Yukawa potential D-dimensional space Nikiforov–Uvarov and amplitude phase methods

Higher order corrections to asymptotic-de Sitter inflation

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Chinese Physics C 2017年第8期41卷 112-117页

作者： m.mohsenzadeh e.Yusofi Department of Physics Qom BranchIslamic Azad UniversityQomIran Department of Physics Ayatollah Amoli BranchIslamic Azad UniversityAmolMazandaranIrana School of Astronomy Institute for Research in Fundamental Sciences(IPM)P.O.Box 19395-5531TehranIran

Since trans-Planckian considerations can be associated with the re-definition of the initial vacuum, we investigate further the influence of trans-Planckian physics on the spectra produced by the initial quasi-de Sitter（d S） state during inflation. We use the asymptotic-d S mode to study the trans-Planckian correction of the power spectrum to the quasi-d S inflation. The obtained spectra consist of higher order corrections associated with the type of geometry and harmonic terms sensitive to the fluctuations of space-time（or gravitational waves） during *** an important result, the amplitude of the power spectrum is dependent on the choice of c, i.e. the type of spacetime in the period of inflation. Also, the results are always valid for any asymptotic d S space-time and particularly coincide with the conventional results for d S and flat space-time.

关键词： initial state trans-Planckian effects inflation

Skew Braces of Size p^(2)q I:Abelian Type

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Algebra Colloquium 2022年第2期29卷 297-320页

作者： e.Acri m.Bonatto ImAS-CONICeT and Universidad de Buenos Aires Pabellon 1 Ciudad Universitaria1428Buenos AiresArgentina Dipartimento di matematica e Informatica Universita di FerraraItaly

This is the first part of a series of two *** this paper we enumerate and classify the left braces of size p^(2)q,where p and q are distinct prime numbers,by the classification of regular subgroups of the holomorph of... 详细信息

关键词： Yang-Baxter equation set-theoretical solution skew brace Hopf-Galois extension

modeling the Spike Response for Adaptive Fuzzy Spiking Neurons with Application to a Fuzzy XOR

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Computer modeling in engineering & Sciences 2018年第6期115卷 295-311页

作者： A.m.e.Ramírez-mendoza CONACYT Research Fellow–State University of Nuevo León(UANL for its acronym in Spanish) Mechanical and Electrical Engineering School(FIME for its acronym in Spanish)Center for Research and Innovation in Aeronautical Engineering(CIIIA for its acronym in Spanish)Carretera a Salinas Victoria km.2.3ApodacaNuevo LeónMéxico

A spike response model(SRm)based on the spikes generator circuit(SGC)of adaptive fuzzy spiking neurons(AFSNs)is *** SRm is simulated in matlabTm *** proposed model is applied to a configuration of a fuzzy exclusive or(fuzzy XOR)operator,as an illustrative example.A description of the comparison of AFSNs with other similar methods is *** novel method of the AFSNs is used to determine the value of the weights or parameters of the fuzzy XOR,first with dynamic weights or self-tuning parameters that adapt continuously,then with fixed weights obtained after training,finally with fixed weights and a dynamic gain or self-tuning gain for a fine adjustment of amplitude.

关键词： Spike response model spikes generator circuit fuzzy XOR adaptive fuzzy spiking neuron learning algorithm fuzzy neuron self-tuning

Formation of AlN from Secondary Al Resources

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Journal of materials Science & Technology 2006年第5期22卷 621-624页

作者： m.Bahgat m.Radwan F.e.Farghaly Central metallurgical Research and Development Institute (CmRDI) P.O.Box 87 Helwan Cairo 11421 Egypt

Synthesis of AlN by NH4Cl-assisted direct nitridation of secondary Al resources was studied. Aluminum alloy scrap contained mg and Zn element was used. milled Al scrap （-1 mm） was mixed with NH4Cl and heated at 1000℃ for 1 h in presence of 1 L/min N2 flow gas. The nitrided product was evaluated by X-ray diffraction semi-quantitative analysis and scanning electron microscopy （Sem）. Aluminium nitride of 90.5% concentration was obtained with a hexagonal crystalline form. AlN is mostly formed in nano-whisker morphology （50～150 nm） which is homogenously distributed.

关键词： AlN Direct nitridation Nanowhisker Secondary resources

Structural and magnetic properties of turmeric functionalized CoFe_2O_4 nanocomposite powder

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Chinese Physics B 2016年第10期25卷 418-422页

作者： e mehran S Farjami Shayesteh m Sheykhan Nanostructures Laboratory Department of Physics University of Guilan Department of Chemistry University of Guilan

The structural and magnetic properties of the synthesized pure and functionalized CoFe2O4magnetic nanoparticles(NPs) are studied by analyzing the results from the x-ray diffraction(XRD), transmission electron microscopy(Tem), FT–IR spectroscopy, thermogravimetry(TG), and vibrating sample magnetometer(VSm). To extract the structure and lattice parameters from the XRD analysis results, we first apply the pseudo-Voigt model function to the experimental data obtained from XRD analysis and then the Rietveld algorithm is used in order to optimize the model function to estimate the true intensity values. Our simulated intensities are in good agreement with the experimental peaks, therefore, all structural parameters such as crystallite size and lattice constant are achieved through this simulation. magnetic analysis reveals that the synthesized functionalized NPs have a saturation magnetization almost equal to that of pure nanoparticles(PNPs). It is also found that the presence of the turmeric causes a small reduction in coercivity of the functionalized NPs in comparison with PNP. Our TGA and FTIR results show that the turmeric is bonded very well to the surface of the NPs. So it can be inferred that a nancomposite(NC) powder of turmeric and nanoparticles is produced. As an application, the anti-arsenic characteristic of turmeric makes the synthesized functionalized NPs or NC powder a good candidate for arsenic removal from polluted industrial waste water.

关键词： cobalt ferrite nanoparticles structural properties magnetic properties turmeric