• Absolute evaluation of ferrous and ferric concentration in Ca amphibole 

      Bahgat, A. A.; Fayek, M. K. ( WILEY-VCH Verlag , 1982 , Article)
      Studies are made of M?sshauer absorption of 57Fe in a Ca-amphibole schist sample at room and liquid nitrogen temperatures. The absolute concentration and the recoilless fraction for ferrous and ferric cations are determined ...
    • Mössbauer study of ZnxNi5/3−xFe1Sb1/3O4 spinel ferrite 

      El Nimr, M.K.; Saleh, H.A.; Fayek, M. K. ( Springer Verlag , 1985 , Article)
      The antimony substituted nickel ferrite ZnxNi5/3–xFe1Sb1/3O4 with different values ofx are prepared, checked by x-ray and studied with57Fe Mössbauer spectroscopy over a wide temperature range. Characteristic spectra of ...
    • Mössbauer effect study of Li21+Me4+Fe63+O122−spinels 

      Saleh, H.A.; El Nimr, M.K.; Nada, N.; Fayek, M. K. ( Baltzer Science Publishers, Baarn/Kluwer Academic Publishers , 1986 , Article)
      Mossbauer effect spectra are obtained for the cubic ferrites Li2 Me Fe6 O12 (where Me4+ is one of the tetravalent elements Ge, Si and Ti) at 78K up to their magnetic transition temperatures. In a rather large temperature ...
    • The Influence of Cation Substitution on the Magnetic Behaviour of Magnesium Ferrite 

      Fayek, M.; Elnimr, M.; Nada, N.; Saleh, H.; Eid, Y. ( WILEY-VCH Verlag GmbH & Co. , 1989 , Article)
      New polycrystalline specimens of the ferrites Mg1.5Fe1Si0.5O4, Mg1.5Fe1Ge0.5O4, Mg1.5Fe1Ti0.5O4 and Mg1.66Fe1Sb0.33O4 have been prepared and studied by nuclear gamma ray resonance technique, over a wide temperature range. ...
    • On the Valence State of Iron in Sr0.52+Ca0.52+Fe0.54+ Me0.54+O32− 

      Fayek, M. K.; Elnimr, M. K.; El Hamalawy, A.; Sekina, M. A. ( WILEY-VCH Verlag GmbH & Co. , 1989 , Article)
      Powder samples of Sr0.5Ca0.5Fe0.5Me0.5O3 (Me = Co, Zr or Mn) and Sr0.3La0.7FeO3 are investigated by X-ray diffraction and Mossbauer effect spectroscopy. Analysis of the completely ordered spectra suggested three kinds ...
    • On Transformations and Perturbations of Orthogonal r-Frames 

      Sherif, N. ( WILEY-VCH Verlag GmbH & Co. , 1993 , Article)
      A decomposition of Cn into a finite direct sum of orthogonal subspaces can be conveniently represented by its orthogonal projector frame, which is the collection of the corresponding orthogonal projectors. Two such ...
    • Effect of gamma radiation on the morphology and Thermophysical properties of the pollen wall of Phoenix dactylifera L. 

      El-Ghazaly, Gamal; Kassem, M.E. ( Qatar University , 1994 , Article)
      Pollen grains of Phoenix dactylifera were exposed to different doses of gamma radiation (250,500,1000 rad and 1 M rad). To access the effect of radiation on the external morphology of the pollen grains, they were examined ...
    • A 6th-order local approximation by a cubic curve 

      Rababah, A.; Ta'ani, A. A. ( Qatar University , 1997 , Article)
      We derive and present a MAPLE program for the construction of a parametric cubic polynomial curve which has sixth-order contract with a given smooth curve at a given point, thus providing a local sixth-order approximation ...
    • The Structure of the Free Volume in Poly(styrene-co-acrylonitrile) from Positron Lifetime and Pressure Volume Temperature (PVT) Experiments 

      Dlubek, Gunter; Bondarenko, Vladimir; Al-Qaradawi, Ilham Y.; Kilburn, Duncan; Krause-Rehberg, Reinhard ( WILEY-VCH Verlag , 2004 , Article)
      Summary: The structure of the free volume and its temperature dependence between 25 and 190 °C of copolymers of styrene with acrylonitrile, SAN (0 to 50 mol-% AN), is studied by pressure volume temperature (PVT) experiments ...
    • On the preparation of electron sensor using LiRbSO4 samples 

      El-Muraikhi, M.; Kassem, M. E.; Gaafar, M.; Abdel Gawad, M. M. H.; Ragab, I. M. ( WILEY-VCH Verlag GmbH & Co. , 2005 , Article)
      The dielectric spectroscopy of metal�metal sulfate LiRbSO4 samples are described with particular emphasis on sensor performance to be used in the field of radiation. The obtained results as the effect of different electron ...
    • Is hypertension a predictor for heart failure? A cross cultural comparison over a 10-year period 

      Bener, A.; Al Suwaidi, J.; Ghaffar, A. ( Elsevier B.V. , 2005 , Article)
      This was a retrospective cohort study to assess the effect of hypertension (HTN) among Qatari and Asian patients admitted to the Hamad General Hospital in Qatar with heart failure (HF) and to identify risk factors that ...
    • Disability, depression and somatization in a low back pain population 

      Bener, Abdulbari; El-Rufaie, Omer F.; Kamran, Saadat; Georgievski, Ana B.; Farooq, Abdulaziz; ... more authors ( Blackwell Publishing Asia , 2006 , Article)
      Objective:  The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods:  This ...

      Baklizi, A. ( Blackwell Publishing Asia Pty Ltd. , 2007 , Article)
      A distribution-free test is proposed for the symmetry of a continuous distribution about a specified median. The test is based on a longest run statistic on the upper portion of the sequence of ordered �centred� observations ...
    • Gamma irradiation effects on polymethyl methacrylate 

      Al-Qaradawi, I. Y.; Abdulmalik, D. A.; Madi, N. K.; Almaadeed, M. ( WILEY-VCH Verlag , 2007 , Article)
      The effect of gamma-irradiation on the structure of polymethyl methacrylate (PMMA) has been investigated. In this study, the PMMA specimens were gamma-irradiated at doses in the range of 0-1000 kGy and measured by means ...
    • An upper bound of the basis number of the semi-strong product of cycles with bipartite graphs 

      Jaradat, Mohammed M.M. ( The Korean Mathematical Society , 2007 , Article)
      An upper bound of the basis number of the semi-strong product of cycles with bipartite graphs is given. Also, an example is presented where the bound is achieved.
    • Weighted estimates for rough parametric Marcinkiewicz integrals 

      Al-Qassem, Hussain Mohammed ( Korean Mathematical Society , 2007 , Article)
      We establish a weighted norm inequality for a class of rough parametric Marcinkiewicz integral operators . As an application of this inequality, we obtain weighted inequalities for a class of parametric Marcinkiewicz ...
    • A rich learning lesson using the Poisson distribution 

      Al-Saleh, Mohammad Fraiwan ( Elsevier B.V. , 2007 , Article)
      In this note, we explore the rich information about inference that the Poisson distribution has. The source of this information is mainly the fact that the mean and variance of this distribution are equal.
    • Homotopy perturbation method for nonlinear partial differential equations of fractional order 

      Momani, Shaher; Odibat, Zaid ( Elsevier B.V. , 2007 , Article)
      The aim of this Letter is to present an efficient and reliable treatment of the homotopy perturbation method (HPM) for nonlinear partial differential equations with fractional time derivative. The fractional derivative is ...
    • A generalized differential transform method for linear partial differential equations of fractional order 

      Odibat, Zaid; Momani, Shaher ( Elsevier B.V. , 2007 , Article)
      In this letter we develop a new generalization of the two-dimensional differential transform method that will extend the application of the method to linear partial differential equations with space- and time-fractional ...
    • Application of generalized differential transform method to multi-order fractional differential equations 

      Ertürk, Vedat Suak; Momani, Shaher; Odibat, Zaid ( Elsevier , 2007 , Article)
      In a recent paper [Odibat Z, Momani S, Erturk VS. Generalized differential transform method: application to differential equations of fractional order, Appl Math Comput. submitted for publication] the authors presented a ...