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A Com.lete Foliation of Schwarzschild Spacetim. by Free Falling Hypersurfaces

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Chinese Physics Letters 2006年第12期23卷 3161-3164页

作者： m. ayub Faridi Am.ad Pervez Haris Rashid Fazal-e-Aleem Centre for High Energy Physics (CHEP) University of the Punjab Lahore 54590 Pakistan Institute of Chem.cal Engineering and Technology University of the Punjab Lahore 54590 Pakistan

Free falling hypersurfaces in the Schwarzschild geom.try have been studied to provide a com.lete foliation of spacetim.. The hypersurfaces do not cross into the m.xim.lly extended spacetim. and are well behaved everyw... 详细信息

关键词： CONSTANT-m.AN-CURVATURE RELATIVITY SURFACES TIm.

Peristaltic flow of William.on fluid in a convected walls channel with Soret and Dufour effects

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International Journal of Biom.them.tics 2016年第1期9卷 223-241页

作者： T. Hayat H. Yasm.n A. Alsaedt m. ayub Departm.nt of m.them.ticsQuaid-I-Azam.University 45320 Islam.bad 44000 Pakistan Departm.nt of m.them.tics Faculty of Science King Abdulaziz University Jeddah 21589 Saudi Arabia Departm.nt of m.them.ticsCOm.ATS Institute of Inform.tion Technology G. T. Road Wah Cantt 47040 Pakistan

Peristaltic flow of m.gnetohydrodynam.c （m.D） William.on fluid in a sym.etric chan- nel is addressed. m.deling is given with Sorer and Dufour effects. Channel walls have com.liant properties. Analysis has been carried out through long wavelength and low Reynolds num.er approach. The obtained series solutions for sm.ll Weissenberg num.er are developed. Im.act of variables reflecting the salient features of wall properties, Blot num.ers and Soret and Dufour on the velocity, tem.erature and concentration has been point out. Trapping phenom.non is also analyzed.

关键词： William.on fluid com.liant walls convective conditions Soret and Dufoureffects.

Influence of Integrated Nutrients on Growth, Yield and Quality of m.ize (Zea m.ys L.)

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Am.rican Journal of Plant Sciences 2011年第1期2卷 63-69页

作者： Azhar Ghaffari Asghar Ali m.ham.ad Tahir m.ham.ad Waseem.m. ayub Asif Iqbal Atta Ullah m.hsin Departm.nt of Agronom. University of Agriculture Faisalabad 38040 Pakistan

A field experim.nt was conducted to evaluate the integrated nutrients effect on growth, yield and quality of m.ize (Zea m.ys L.) during spring, 2009, at the Agronom.c Research Area, University of Agriculture, Faisalabad. The ex-perim.nt was laid out in Random.zed Com.lete Block Design (RCBD) having three replications with following treat-m.nts: T1 (control), T2(recom.ended NPK @ 200-120-125 kg ha-1), T3 [single spray of m.ltinutrient (a solution m.xture of m.cronutrients i.e;Zn = 2%, Fe = 1%, B = 1%, m. = 1%, Cu = 0.2% and m.cronutrients N = 1%, K2O = 2%, S = 2%) @ 1.25Lha-1], T4 (recom.ended NPK @ 200-120-125 kg ha-1 + single spray of m.ltinutrient @ 1.25L ha-1), T5 (recom.m.nded NPK @ 200-120-125 kg ha-1 + two spray of m.ltinutrient @1.25Lha-1) and T6 (recom.ended NPK @ 200-120-125 kg ha-1+ three spray of m.ltinutrient @ 1.25Lha-1).The recom.ended dose of NPK in addition with single spray of m.lti-nutrients substationally im.roved all growth param.ters, ear characteristics and also enhanced m.cronutrients use efficiency up to 11.5% which induced significant increase in grain yield as com.ared to control and also in the treatm.nt where recom.ended dose of NPK was applied alone. The quality param.ter of m.ize (oil contents) significantly im.roved by foliar application of m.ltinutrients solution but recom.ended dose of fertilizer in addition to single spray of m.lti-nutrients was econom.cal.

关键词： m.lti-Nutrients Foliarapplication Nutrients Use Efficiency Oil Content

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底水油藏：模拟方法

国外石油动态 2008年第18期 29-39页

作者： K. ELKADDIFI E. SHIRIF m. ayub A. HENNI 常伟（译）

在萨斯喀彻温省和阿尔伯达省的许多轻度或者中度粘性油藏，不同厚度和范围（底水层）的高水位不活跃水饱和带与其上面的含油带相伴而生。结果，一次采油周期很短，并且储层很早就发生水突破。之后，在二次采油阶段内，这样的高度不活跃... 详细信息

在萨斯喀彻温省和阿尔伯达省的许多轻度或者中度粘性油藏，不同厚度和范围（底水层）的高水位不活跃水饱和带与其上面的含油带相伴而生。结果，一次采油周期很短，并且储层很早就发生水突破。之后，在二次采油阶段内，这样的高度不活跃水饱和带还会对注水效率产生负面影响。本文重点讨论向此类储层注水的问题。本文的重点是，降低底水层中的水流度，从而实现更有效的驱油。一种商业模拟器（Cm.的Im.X）曾被用于这种小规模的研究。不同浓度的聚合物被用作底水层堵水剂和含油带中的流度控制剂。研究了降低底水层中的水流度并改善垂向波及系数的不同战略。检查的变量包括渗透率、油粘度、相对于油层的厚度、聚合物浓度、注入速度与注入点、垂直与水平注入的影响以及生产井的组合。结果显示，通过封堵底水层，使层与层之间的交叉流动最小化，可以增加采油。还发现，对于不利的流度比而言，随着注入速度的增加，最终采收率也会增加。聚合物溶液的注入对注水动态有积极影响。此外，传统的注水动态越差，作为流度和封堵控制剂的聚合物就越有效。在底水条件下对储层进行常规注水的情况下，水平井的采油效果比垂直井稍稍好一些。此外，由于增加了扫油面积，某些井组合（水平生产与垂直注水）提供了更好的采油效果。

关键词：底水油藏模拟方法聚合物浓度注入速度一次采油注水动态萨斯喀彻温流度比

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英国出售的和从孟加拉进口的食物中砷调查

水文地质工程地质技术方法动态 2005年第6期 1-6页

作者： S.W. AI Rm.LLI P.I. HARRIS C.F. HARRINGTON, m. ayub 葛秀珍（译）

砷是具有很高毒性的元素，食物中砷的存在关系到人类和动物是否能够很好地生存的问题。在孟加拉和孟加拉西部与印度接壤地带常常因为被砷污染的地下水浇灌种植的农作物以及该区的动物食用了这些农作物，这就可能造成了砷进入人类食物链... 详细信息

砷是具有很高毒性的元素，食物中砷的存在关系到人类和动物是否能够很好地生存的问题。在孟加拉和孟加拉西部与印度接壤地带常常因为被砷污染的地下水浇灌种植的农作物以及该区的动物食用了这些农作物，这就可能造成了砷进入人类食物链。在这个研究中，作者使用石墨炉原子吸收光谱测试法测定从孟加拉国进口到英国的粮食中总砷浓度的范围，包括蔬菜、大米和鱼类。在所有从孟加拉国进口的蔬菜中，总砷的平均浓度和范围分别是54．5和5—540μg／kg。在海芋植物的皮中发现砷的值最高540μg／kg，接下来是海芋植物的颈168μg／kg，和苋属160μg／kg。在其他样品中，淡水鱼含有的总砷的浓度在97和1318μg／kg之间。英国产的蔬菜中砷的含量大约低于从孟加拉国进口的蔬菜的观察值2—3倍。这个研究的一些实例中，发现从孟加拉进口的蔬菜中砷的浓度与以前记录的与孟加拉西部接壤的印度受砷影响的区域生长的蔬菜的砷浓度相似，但是低于记录的正在研究的从孟加拉进口的蔬菜的浓度。同时，在研究中测定出从孟加拉进口的蔬菜的总砷的浓度远远低于推荐的砷的最大允许浓度，它提供了食物中砷的一个额外的来源。这种浓度升高的可能性（即通过某些地区英国人口摄取的砷也许大大地高于当时总人口的摄入量）需要进一步调查。

关键词：石墨炉原子吸收光谱测试法砷食物孟加拉食物

Energy transport for ion acoustic waves in a spin polarized quantum.plasm.

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Com.unications in Theoretical Physics 2020年第1期72卷 124-129页

作者： m.ayub Z Iqbal H A Shah G m.rtaza Salam.Chair Department of PhysicsG.C.UniversityKatchery RoadLahore 54000Pakistan Departm.nt of Physics G.C.UniversityKatchery RoadLahore 54000Pakistan Departm.nt of Physics Mirpur University of Science and TechnologyMirpur-10250(AJK)Pakistan

The separate spin evolution quantum.hydrodynam.cs(SSE-QHD)m.del is used to investigate the energy behavior for ion acoustic waves in degenerate quantum.*** results show that the energy flow speed decreases with spin polarization *** is also shown that it decreases with the increasing rate up to a certain range of wave num.er and then it goes to zero *** is observed that Bohm.potential suppresses the energy flow *** is also noticed that the energy flow speed deviates from.the group velocity even in the absence of Bohm.potential ***,the contribution of of Bohm.poential effect in spin polarized plasm. reduces the extent of deviation.

关键词： spin polarization quantum plasm. ion acoustic wave energy flow speed

Stokes'first problem.for the fourth order fluid in a porous half space

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Acta m.chanica Sinica 2007年第1期23卷 17-21页

作者： T.Hayat F.Shahazad m.ayub Departm.nt of m.them.tics Quaid-I-Azam University 45320Islamabad 44000Pakistan

In this study, the flow of a fourth order fluid in a porous half space is m.deled. By using the m.dified Darcy＇s law, the flow over a suddenly m.ving flat plate is studied num.rically. The influence of various param.... 详细信息

关键词： Fourth order fluid Porous space Num.rical solution m.dified Darcy's law

A native herbaceous com.unity exerts a strong allelopathic effect on the woody range-expander Betula fruticosa

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Journal of Plant Ecology 2024年第4期17卷 131-140页

作者： Lichao Wang ayub m.O.Oduor Yanjie Liu State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China University of Chinese Academ. of Sciences Beijing 100049China Departm.nt of Applied Biology Technical University of KenyaNairobiKenya

Biological invasions by alien and range-expanding native plant species can suppress native plants through ***,the hom.land security hypothesis suggests that som. native plants can resist invasion by producing allelopathic com.ounds that inhibit the growth of invasive *** research has focused on allelopathic interactions between individual native and invasive plant species,with less em.hasis on how allelopathy helps entire native com.unities resist ***,lim.ted knowledge exists about allelopathic interactions between range-expanding native species and recipient native com.unities,and their influence on invasion *** bridge this knowledge gap,we conducted two greenhouse com.etition experim.nts to test reciprocal allelopathic effects between a native woody range-expanding species,Betula fruticosa,and a com.unity of four native herbaceous species(Sanguisorba officinalis,Gentiana m.nshurica,Sium.suave and Deyeuxia angustifolia)in *** assessed whether *** and the native com.unity differed in their com.etitive effects and responses,and whether these were influenced by activated carbon,which neutralizes allelochem.cals in the *** carbon reduced the suppressive effects of the native com.unity on the above-ground biom.ss of ***,which indicates that the native com.unity exerted a strong allelopathic effect on *** contrast,activated carbon only m.rginally enhanced the suppressive effects of *** on the native com.unity,which indicates that allelopathy is not the prim.ry m.chanism.by which *** exerts its ***,these findings support the hom.land security hypothesis and suggest that biotic resistance from.the native herbaceous com.unity m.y lim.t the invasion success of the woody range-expander ***.

关键词： allelochem.cals com.etition encroachm.nt global change non-native shrub

Dust-Lower-Hybrid Surface Waves in Classical and Degenerate Plasm.s

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Com.unications in Theoretical Physics 2013年第11期60卷 623-629页

作者： m.ayub H.A.Shah m.N.S.Qureshi m.Salim.llah Departm.nt of Physics G. C. University Departm.nt of Physics Mirpur University of Science and Technology (MUST) Departm.nt of Physics Jahangirnagar University

The dispersion relation for general dust low frequency electrostatic surface waves propagating on an interface between a m.gnetized dusty plasm. region and a vacuum.is derived by using specular reflection boundary conditions both in classical and quantum.regim.s. The frequency lim.t ω ≤ωei ≤ ωce is considered and the dispersion relation for the Dust-Lower-Hybrid Surface Waves （DLHSW＇s） is derived for both classical and quantum.plasm. half-space and analyzed num.rically. It is shown that the wave behavior changes as the quantum.nature of the problem.is considered.

关键词： dusty plasm. lower hybird surface wave degenerate plasm.