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Mathematical Modeling and Simulation of Thermally Stimulated Current علاء الدين القطب عبد القادر محمد

In this work the dipole-dipole interaction model which was proposed by the
author using dipole-dipole interaction concept is reformulated to account also
for the energy distribution function. This lead to deveolpe four models of
mono-energy (MEAM, and MEWM) and distributed energy (EDMA, and
EDMW). A numerical studies was conducted to account for the validity of
these models. Using a computer simulated mono-energetic peak calculated at
difenet peak parameters (E, and τo) as a test peak for all four models. Then the
peak parameters (E, and τo) was compared in addition to the quality of fitting
of all four models.

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Modelling of Thermally Stimulated Depolarization Current (TSDC) Using Dipole-Dipole interaction Concept. علاء الدين القطب عبد القادر محمد

The study of thermally stimulated depolarization current (TSDC) using the dipole–dipole interaction
modelisdescribedinthiswork.Thedipole–dipoleinteractionmodel(DDIM)determinestheTSDCpeaksuccessfully
since it gives significant peak parameters (i.e. activation energy (E) and pre-exponential factor (τ0)) in addition to
the dipole–dipole interaction strength parameter (di). Application of this model to study the peak parameters of
some polymeric systems is presented.

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Computation of Dipole-dipole interaction Energy in Amorphous Polymers علاء الدين القطب عبد القادر محمد

In this work investigation of dipole-dipole interaction energy was made using
(TSDC) experimental technique deconvoluted by Thermal sampling (TS)
technique (TS-TSDC) the peaks were analyzed using a proposed model
based on the dipole-dipole interaction concept (DDIM) . The proposed model
describes the (TS-TSDC) peaks and gives a significant peak parameters (i.e.
Activation energy (E) and the pre-exponential factor (το) in addition to the
dipole-dipole interaction energy parameter (di). Application of this model to
determine the peak parameters of polyvinyl chloride(PVC) amorphous
polymer (TS-TSDC) data is presented . The results of the model was
compared to a well known peak shape methods namely, the Initial rise, the
half width, in addition to Cowell and Wood analysis.

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Comparative modeling studies of TSDC: investigation of Alpha- relaxation in Amorphous polymers علاء الدين القطب عبد القادر محمد

A model to investigate Thermally Stimulated Depolarization Current (TSDC) peak
parameters using the dipole-dipole interaction concept is proposed by the author in
this work. The proposed model describe the (TSDC) peak successfully since it
gives a significant peak parameters (i.e. Activation energy (E) and the per-
exponential factor (το) in addition to the dipole-dipole interaction strength parameter
(di). Application of this model to determine the peak parameters of polyvinyl
chloride(PVC) polymer is presented . The results show how the model fit the
experimental thermal sampling data. Finally the results are compared to the well
know techniques; the initial rise method (IR), the half width method (HW) in
addition to the Cowell and Woods analysis..

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Lithiation and Substitution of N′ (ω Phenylalkyl)-N,N-dimethylureas محمد بطاح الشمري

Lithiation of N-[2-(4-methoxyphenyl)ethyl]pivalamide at –20 to 0 °C with three equivalents of n-BuLi in anhydrous THF, followed by reactions with various electrophiles, gives high yields of products involving ring substitution ortho to the pivaloylaminoethyl group, which was unexpected in view of earlier results reported with t-BuLi.

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Variation in the Site of Lithiation of 2‑(2-Methylphenyl)ethanamine Derivatives محمد بطاح الشمري

Unexpectedly, lithiation of N′-(2-(2-methylphenyl) ethyl)-N,N-dimethylurea with 3 equiv of n-butyllithium in anhydrous THF at 0 °C takes place on the nitrogen and on the CH2 next to the 2-methylphenyl ring (α-lithiation). The lithium reagent thus obtained reacts with various electrophiles to give the corresponding  ubstituted derivatives in excellent yields. Similarly, lithiation of N-(2-(2-methylphenyl)ethyl)pivalamide under similar reaction conditions followed by reaction with benzophenone as a representative electrophile gave the corresponding α-substituted product in high yield. Surprisingly, no products resulting from lateral lithiation ere observed under the conditions tried, which sharply contrasts with the reported results for lateral lithiation of tert-butyl (2-(2-methylphenyl)ethyl)carbamate.

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SIDE-CHAIN LITHIATION OF 2- AND 4-SUBSTITUTED PYRIDINES: SYNTHESIS OF MORE COMPLEX SUBSTITUTED PYRIDINES محمد بطاح الشمري

Lithiation of pyridines substituted in the 2- and 4-positions by acylaminomethyl groups, namely of the corresponding N-(pyridinylmethyl)pivalamides, N'-(pyridinylmethyl)-N,N-dimethylureas and tert-butyl N-pyridinylmethylcarbamates, with two mole equivalents of t-BuLi in anhydrous THF at -78 C takes place on the nitrogen and on the methylene group of the side-chain. The lithium reagents thus obtained react with a variety of electrophiles to give the corresponding side-chain substituted derivatives in high yields.

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Asymmetric Addition of Diethyl Zinc to Benzaldehyde Catalyzed by Chiral Diamine Ligand and Ti-diamine Modified Complex Derived from D-mannitol محمد بطاح الشمري

Modified procedure for preparation of chiral: 3,4-Diazido-1, 2:5, 6-di-O-isopropylidene-Dmannitol from the corresponding bismesylate and new chiral ligand: 3, 4-diamino-1, 2:5, 6-Oisopropylidene-D-annitol was described. The application of both diamine and Ti-diamine complex as catalysts in enantioselective addition of diethyl zinc to prochiral benzaldehyde was described. High enantioselectivity up to 93% e.e. was achieved. The standard analytical measurements including optical activity of the diazide, diamine and the determination of optical purity of the resulting alcohol were reported.

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الشهادة كأداة إثبات في المملكة العربية السعودية والقانون المقارن سيف ابراهيم آل خميس

في هذا البحث قمت بشرح الشهادة وأثرها من الإثبات في الفقه الإسلامي خاصة الفقه الحنبلي و نظام المرافعات الشرعية السعودي مقارنا ببعض الأنظمة المجاورة خاصة النظام المصري

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Effect of glycine betaine and salicylic acid on growth and productivity of droughted Wheat cultivars: Image analysis for measuring the anatomical features in flag leaf and peduncle of the main shoot عبير حمدي الحكيم

 

H. S. Aldesuquy, S. A. Abo- Hamed, M. A. Abbas and A. H. Elhakem, (2013). J. of Stress Physiology & Biochemistry, Vol. 9 No. 2 2013, pp. 35-63 ISSN 1997-0838

   The present study was planned to investigate the possible role displayed by water stress and application of GB, SA or their interaction on some anatomical features in flag leaf at anthesis (after 95 days from sowing) by measuring leaf thickness, ground tissue thickness, number of hairs, metaxylem vessel area, xylem vessel area, phloem tissue area, vascular bundle tissues area, number of motor cells as well as number of opened and closed stomata on both upper and lower epidermis and some anatomical features of peduncle (peduncle diameter, tracheids area, metaxylem vessel area, xylem area, phloem area, vascular area, number of vascular bundle as well as opened and closed stomata) of the two wheat cultivars. Water stress markedly affected the anatomical features in flag leaves of both wheat cultivars. It caused massive decreases (P< 0.05) in the leaf thickness, ground tissue thickness, number of hairs, metaxylem vessel area, xylem vessel area, phloem tissue area, vascular bundle area, number of motor cells as well as number of opened stomata on both upper and lower epidermis. On the other hand, water stress increased (P< 0.05) the number of hairs and closed stomata on both upper and lower epidermis in flag leaves of the two wheat cultivars. The magnitude of decrease in all anatomical features in...

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