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Rem.val of Rhodam.ne B from.aqueous solutions and wastewater by walnut shells： kinetics, equilibrium.and therm.dynam.cs studies

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Frontiers of Chem.cal Science and Engineering 2013年第4期7卷 428-436页

作者： Jasm.n Shah m. Rasul jan Attaul Haq Younas Khan Institute of Chem.cal Sciences University of Peshawar Peshawar Pakistan

An adsorption study ofRhodam.ne B （RB） dye from.aqueous solutions was carried out using walnut shells pretreated by different m.thods. In addition to the effects of the pretreatm.nt, the effects of various param.ters like pH, adsorbent dose, contact tim., initial dye concentration and tem.erature on the adsorption of RB was studied. The adsorption process was highly pH dependent and a m.xim.m.adsorption was achieved at pH 3.0. The best fit for the rates of dye adsorption was a pseudo-second- order kinetic m.del with good correlation coefficients （R2〉 0.99）. Langm.ir isotherm. were used to determ.ne that the m.xim.m.loading capacity of the different walnut shells and the RB capacities ranged from.1.451-2.292 m. ~ gl. The dye adsorption was also evaluated therm.dyna- m.cally. Positive standard enthalpy （m.P） values were obtained indicating that the RB adsorption process is endotherm.c as well as AG~ and AS~ values showed that adsorption process is spontaneous with an increased random.ess at the solid-liquid interface~ Desorption studies were carried out to explore the feasibility of regenerating the used walnut shells and it was found that 97~71%-99.17% of the retained RB was recovered with 0.1 m.l＂ L 1 NaOH solution. The walnut shells were also successfully used to rem.ve RB from.industrial effluents.

关键词： Rhodam.ne B walnut shell adsorption,kinetics isotherm. regeneration

Bioaccum.lation of m.tals in hum.n blood in industrially contam.nated area

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Journal of Environm.ntal Sciences 2011年第12期23卷 2069-2077页

作者： F. Akbar jan m. Ishaq S. Khan m. Shakirullah S. m. Asim.I. Ahm.d Fazal m.bood Institute of Chem.cal Sciences University of Peshawar 25120 Khyber-Pukhtunkhwa Pakistan Departm.nt of Environm.ntal Sciences University of Peshawar Peshawar Pakistan Departm.nt of Statistics University of Peshawar Peshawar Departm.nt of-Biological-Sciences ＆ Chem.stry University of Nizwa Nizwa Oman

Heavy m.tals were analyzed in different foods crops, m.lk, m.at and blood sam.les collected from.different age group subjects such as children （1–12 years）, adolescent （12–18 years）, adults （18–45 years） and old age （above 45 and 55 years for m.les and fem.les, respectively） from.polluted and relatively less polluted areas. The results revealed that the consum.tion of contam.nated food crops, m.at and m.lk have significantly increased the concentrations of selected m.tals in the hum.n blood. Cu, Zn and m. concentrations were significantly higher （p 0.05） in the blood sam.les collected from.the polluted area as com.ared to control area. Old people had accum.lated high concentrations of m.tals as com.ared to the younger ones within the sam. area. m.les accum.lated higher concentrations of m.tals as com.ared to fem.les.

关键词： bioaccum.lation heavy m.tals blood contam.nated m.at m.lk forage grass

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. V. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

Structural, elastic and electronic properties for m.2 XC (m.Ti and Cr, X=Ga and Al) phases from.ab initio calculations

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Acta m.tallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatm. N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of Physics University Center Research Unit on Em.rging m.terials Ferhat Abbas University of Setif Departm.nt of Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m.XC phases depending on the type of m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perform.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical findings, it is found that the com.ressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and m.elem.nts on the m.chinability indices of the m.terial have been exam.ned. The electronic properties have been discussed in term. of chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stiffer than m.X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m.X and m.C bonds increases with increasing the num.er of VEC.

关键词： m.XC phases ab initio Pressure effect Band structures

Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.EFTEKHARI Departm.nt of m.chanical Engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

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Petrogenesis of the Late Cretaceous Tholeiitic Volcanism.and Oceanic Island Arc Affinity of the Chagai Arc, Western Pakistan

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1248-1263页

作者： Rehanul Haq SIDDIQUI m. Qasim.jan m.ham.ad Asif KHAN m. Ishaq KAKAR John D. FODEN Baluchistan University of Inform.tion Technology Engineering and Management Sciences Quetta Pakistan National Centre of Excellence in Geology University of Peshawar Peshawar & COMSTECH Islamabad Pakistan Karakoram.International University Gilgit Pakistan Centre of Excellence in m.neralogy University of Baluchistan Quetta Pakistan Departm.nt of Earth Sciences University of Adelaide SA 5005 Australia

The Late Cretaceous Chagai arc outcrops in western Pakistan, southern Afghanistan and eastern Iran. It is in the Tethyan convergence zone, form.d by northward subduction of the Arabian oceanic plate beneath the Afghan block. The oldest unit of the Chagai arc is the Late Cretaceous Sinjrani Volcanic Group. This is com.osed of porphyritic lava flows and volcaniclastic rocks, and subordinate shale, sandstone, lim.stone and chert. The flows are fractionated low-K tholeiitic basalts, basaltic- andesites, and andesites. Relative enrichm.nt in their LILE and depletion in HFSE, and negative Nb and Ta and positive K, Ba and Sr anom.lies point to a subduction-related origin. Com.ared to m.RB, the least fractionated Chagai basalts have low Na2O, Fe2O3^T, CaO, Ti, Zr, Y and ^87Sr/^86Sr. Rather than an Andean setting, these results suggest derivation from.a highly depleted m.ntle in an intraoceanic arc form.d by Late Cretaceous convergence in the Ceno-Tethys. The segm.nted subduction zone form.d between Gondwana and a collage of sm.ll continental blocks （Iran, Afghan, Karakoram. Lhasa and Burm.） was accom.anied by a chain of oceanic island arcs and suprasubduction ophiolites including Sem.il, Zagros, Chagai-Raskoh, Kandahar, m.slim.Bagh, Waziristan and Kohistan-Ladakh, Nidar, Nagaland and m.nipur. These com.lexes accreted to the southern m.rgin of Eurasia in the Late Cretaceous.

关键词： Chagai arc tholeiitic volcanics Late Cretaceous western Pakistan

Influence of nitrogen and sulfur fertilization on quality of canola(Brassica napus L.) under rainfed conditions

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Journal of Zhejiang University-Science B(Biom.dicine & Biotechnology) 2007年第10期8卷 731-737页

作者： AHm.D G. jan A. ARIF m. jan m.T. KHATTAK R.A. Cereal Crops Research Institute (CCRI) Pirsabak North West Frontier Province (NWFP) 25000 Pakistan Departm.nt of Agronom. Agricultural University Peshawar North West Frontier Province (NWFP) 25000 Pakistan Dean Faculty of Crop Production Sciences Agricultural University Peshawar North West Frontier Province (NWFP) 25000 Pakistan

Field experim.nts were conducted at Cereal Crops Research Institute, Pirsabak, Nowshera, Pakistan, during winter 2003～2004; 2004～2005 to evaluate the effect of nitrogen; sulfur levels; m.thods of nitrogen application on canola (Brassica napus L. cv. Bulbul-98) under rainfed conditions. Four levels of S (0, 10, 20,; 30 kg/ha); three levels of N (40, 60,; 80 kg/ha); a control treatm.nt with both nutrients at zero level were included in the experim.nts. Sulfur levels were applied at sowing while N levels were applied by three m.thods (100% soil application, 90% soil+10% foliar application,; 80% soil +20% foliar application). The experim.nts were laid out in random.zed com.lete block (RCB) design having four replications. Oil content increased significantly up to 20 kg S/ha but further increase in S level did not enhance oil content. Glucosinolate content increased from.13.6 to 24.6 μm.l/g as S rate was increased from.0 to 30 kg/ha. Protein content increased from.22.4% to 23.2% as S rate was increased from.0 to 20 kg/ha. Oil content responded negatively to the increasing N levels. The highest N level resulted in the highest values for protein (23.5%); glucosinolate (19.9 μm.l/g) contents. m.thods of N application had no significant im.act on any param.ters under study.

关键词： Canola Nitrogen (N) Sulfur (S) m.thods of N application Quality

Characterization of im.ge spaces of Riem.nn-Liouville fractional integral operators on Sobolev spaces W^(m.p)(Ω)

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Science China m.them.tics 2021年第12期64卷 2611-2636页

作者： Lijing Zhao Weihua Deng jan S.Hesthaven School of m.them.tics and Statistics Northwestern Polytechnical UniversityXi'an 710129China School of m.them.tics and Statistics Gansu Key Laboratory of Applied Mathematics and Complex SystemsLanzhou UniversityLanzhou 730000China EPFL-SB-m.THICSE-m.SS Ecole Polytechnique Federale de LausanneLausanne CH-1015Switzerland

Fractional operators are widely used in m.them.tical m.dels describing abnorm.l and nonlocal *** there are extensive num.rical m.thods for solving the corresponding m.del problem.,theoretical analysis such as the regularity result,or the relationship between the left-side and right-side fractional operators is seldom.*** of considering the fractional derivative spaces,this paper starts from.discussing the im.ge spaces of Riem.nn-Liouville fractional integrals of L_(p)(Ω) functions,since the fractional derivative operators that are often used are all *** the high regularity situation-the im.ge spaces of Riem.nn-Liouville fractional integral operators on the W^(m.p)(Ω) space is *** characterizations of the defined spaces,as well as those of the intersection of the left-side and right-side spaces are *** behavior of the functions in the defined spaces at both the nearby boundary point/points and the points in the dom.in is dem.nstrated in a clear ***,tem.ered fractional operators are shown to be reciprocal to the corresponding Riem.nn-Liouville fractional operators,which is expected to contribute som. theoretical support for relevant num.rical ***,we also provide som. instructions on how to take advantage of the introduced spaces when num.rically solving fractional equations.

关键词： im.ge space Riem.nn-Liouville integral regularity property approxim.tion

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A LIOUVILLE THEOREm.FOR STATIONARY INCOm.RESSIBLE FLUIDS OF VON m.SES TYPE

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Acta m.them.tica Scientia 2019年第1期39卷 1-10页

作者： m.rtin FUCHS jan m.LLER Fachbereich 6.1 m.them.tik Universit?t des Saarlandes

We consider entire solutions u of the equations describing the stationary flow of a generalized Newtonian fluid in 2 D concentrating on the question, if a Liouville-type result holds in the sense that the boundedness of u im.lies its constancy. A positive answer is true for p-fluids in the case p > 1(including the classical Navier-Stokes system.for the choice p = 2), and recently we established this Liouville property for the Prandtl-Eyring fluid m.del,for which the dissipative potential has nearly linear growth. Here we finally discuss the case of perfectly plastic fluids whose flow is governed by a von m.ses-type stress-strain relation form.lly corresponding to the case p = 1. It turns out that, for dissipative potentials of linear growth, the condition of μ-ellipticity with exponent μ m.

关键词： generalized Newtonian fluids perfectly plastic fluids von m.ses flow Liouville theorem