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Grid System Analysis of Urban Flora of Bukhara City (Uzbekistan)  [PDF]
Abdulla M. Umedov, Husniddin K. Esanov
American Journal of Plant Sciences (AJPS) , 2024, DOI: 10.4236/ajps.2024.152010
Abstract: This article presents information on the study of the flora of Uzbekistan based on grid system mapping. The urban flora of the city of Bukhara was researched in it. As a result of research, the territory of Bukhara city was divided into 85 indexes based on 1 × 1 km2 grid mapping system. The diversity and density of species in the indexes are determined. The influence of anthropogenic factors on the diversity of species in the indexes is determined.
Two Photon Absorption in Nanostructure Wide Band Gap Semiconductor CdS Using Femtosecond Laser  [PDF]
Abdulla M. Suhail, Raied K. Jamal, Hani J. Kbashi
Advances in Materials Physics and Chemistry (AMPC) , 2011, DOI: 10.4236/ampc.2011.13011
Abstract: Strong nonlinear absorption in CdS nanoparticles of dimensions in the range 4 - 50 nm when irradiated with a femtosecond pulsed laser at 800 nm is observed. The CdS nanoparticles sizes were controlled by changing the reaction time of aqueous solutions of thiourea and cadmium chloride. The structure of the prepared CdS nanoparticles were tested and their optical properties were investigated and the nonlinear absorption coeffi-cients were measured using a fully computerized z-scan unit. It is found that the formation of the CdS nanos-tructuresfor are responsible for the observation of the strong tow photon absorption.
Three-Photon Absorption in Zno Film Using Ultra Short Pulse Laser  [PDF]
Raied K. Jamal, Mohammed T. Hussein, Abdulla M. Suhail
Journal of Modern Physics (JMP) , 2012, DOI: 10.4236/jmp.2012.38112
Abstract: The three-photon absorption (3PA) in nanostructure wide-band gap ZnO semiconductor material is observed under high intensity femtosecond Titanium-Sapphire laser of 800 nm wavelength excitation. The ZnO film was prepared by chemical spray pyrolysis technique with substrate temperature of 400℃. The optical properties concerning the absorp-tion, transmission, reflection, Raman and the photoluminescence spectra are studied for the prepared film. The structure of the ZnO film was tested with the X-Ray diffraction and it was found to be a polycrystalline with recognized peaks oriented in (002), and (102). The measured of three photon absorption coefficient was found to be about 0.0166 cm3/Gwatt2, which is about five times higher than the bulk value. The fully computerized z-scan system was used to measure the nonlinear coefficients from the Gaussian fit of the transmitted laser incident.
HEAT TRANSFER CHARACTERISTICS OF A NUCLEAR FUEL ROD COOLED IN A SURROUNDING MEDIUM –A COMPARITIVE STUDY BETWEEN 1-D & 2-D ANALYSIS
FARES ABDULLA,MOHAMMED NAZAR,NAGEEM SHAFI,ABDULLA M.M
International Journal of Engineering Science and Technology , 2012,
Abstract: This paper presents the comparison of the heat transfer characteristics of a two-dimensional model of a nuclear fuel rod cooled in a surrounding medium with those of one- dimensional model. The equations governing the temperature field both for one and two-dimensional models are solved numerically using second order finite difference schemes. Thermal performance characteristics of the two-dimensional model of the fuel rod is obtained for a wide range of aspect ratio Ar, Biot number Bi, and heat generation parameter Q and compared with those of respective one-dimensional model. It is observed that for Ar 7.0, Bi and Q being kept fixed, onedimensionalmodel prediction is found to be quite satisfactory. Furthermore, for fixed values of Ar and Bi, there exists a limiting value of Q below which one-dimensional model prediction is valid. It is also noticed that for fixed values of Ar and Q and Bi 1.5, one-dimensional model prediction is in fairly good agreement with that of two-dimensional one.
Anti-inflammatory and analgesic activities of some newly synthesized pyridinedicarbonitrile and benzopyranopyridine derivatives
Hanaa M. Hosni, Mohamed M. Abdulla
Acta Pharmaceutica , 2008, DOI: 10.2478/v10007-008-0005-4
Abstract: In continuation of our search for new substituted pyridine based anti-inflammatories, reaction of 1-(2-thienyl or furanyl)-3-(2-hydroxyphenyl)-2-propen-1-ones (1) with malononitrile in alcoholic KOH solution afforded a mixture of 4-alkoxy-2-(2-thienyl or furanyl)-5H-[1]benzopyrano[3,4-c]pyridine-5-ones (2) and 2-alkoxy-4-amino-6- (2-thienyl or furanyl)-3,5-pyridinedicarbonitriles (3). Some of the synthesized compounds were evaluated for their anti-inflammatory and analgesic activities compared to diclofenac potassium as positive control. Detailed synthesis, spectroscopic and toxicity data are reported.
Vitamin D Deficiency and Pseudofractures in Child-Bearing Egyptian Women: Successful Medical Treatment Helps to Avoid Fractures and Surgical Interference  [PDF]
Ghada M. El-Sagheer, Elwy Soliman, Ahlam M. Abdulla, Mohamed Ali
Open Journal of Endocrine and Metabolic Diseases (OJEMD) , 2016, DOI: 10.4236/ojemd.2016.68024
Abstract: Background: Recent evidence for the effects of vitamin D and recognition of the high prevalence of its deficiency has increased the interest in it. Vitamin D-sub nutrition may contribute to the risk of a wide range of disorders. Methods: The females in the child-bearing period attending the endocrinology and orthopedic out-patient clinics complaining of pain and/or tenderness at the groin were evaluated. Patients with chronic metabolic or skeletal illness, primary hyperparathyroidism, andpatients receiving drugs that interfere with bone mineral metabolisms were excluded. One hundred accepted and consented to participation in the study. All the participants were subjectedto full history taking, clinical evaluation, laboratory investigations including serum Ca, Ph, PTH,ALP, TSH, F T4, F T3, Cortisol level, and 25(OH)D level. Plain X-ray was done for the regions of bony tenderness. The subjects were divided into 2 groups based on the presenceor absence ofpseudo-fractures (looser zones). They were treated and followed up till normalization of the laboratory parameters and healing of the looser zones. Results: The mean age for patients was 30.45 ± 5.8, their mean 25(OH) vitamin D level was 14.7 ± 5.9 ng/ml, the mean PTH was 195.7 ± 162.6, and looser zones were evident in the X-rays of 34 patients. The serum 25(OH)D showed significant negative correlations with veiling, parity, localized hip pain, and tenderness, ALP, PTH, but, a significant positive correlation with sun exposure, dairy products consumption, vitamin D supplementation, and serum calcium levels. The independent factors associated with hypovitaminosis D were the lack of sun exposure, lack of vitamin D supplementation, and the presence of pseudo- fracture (p ≤ 0.009, 0.038, and 0.001 respectively). No surgery was required in any of
Protuupalno i analgetsko djelovanje novih derivata piridindikarbonitrila i benzopiranopiridina
M. ABDULLA, MOHAMED,M. HOSNI, HANAA
- , 2008, DOI: 10.2478/v1007-008-0005-4
Abstract: Sa?etak U nastavku istra?ivanja derivata piridina s potencijalnim protuupalnim djelovanjem sintetizirani su 4-alkoksi-2-(2-tienil ili furanil)-5H-[1]benzopirano[3,4-c]piridin-5-oni (2) i 2-alkoksi-4-amino-6-(2-tienil ili furanil)-3,5-piridindikarbonitrili (3). Smjesa spojeva 2 i 3 dobivena je reakcijom 1-(2-tienil ili furanil)-3-(2-hidroksifenil)-2-propen-1-ona (1) s malononitrilom u alkoholnoj otopini KOH. Neki od sintetiziranih spojeva testirani su na protuupalno i analgetsko djelovanje, uz diklofenak kalij kao pozitivnu kontrolu. U radu su dani detaljni sintetski, spektroskopski i toksikolo?ki podaci
Tannin–Phenol Formaldehyde Resins As Binders for Cellulosic Fibers: Mechanical Properties  [PDF]
A.S. Hussein, K.I. Ibrahim, K. M. Abdulla
Natural Resources (NR) , 2011, DOI: 10.4236/nr.2011.22013
Abstract: In this study Eucalyptus tannin (T) was isolated from outer bark of Eucalyptus trees; as sodium phenoxide salt and used as extender or copolymer into phenol formaldehyde (PF) resin at five percent (10, 20, 30, 40 and 50)% W/W. Tan-nin-phenol formaldehyde (TPF) and tannin formaldehyde-phenol formaldehyde (TFPF) resins that synthesized in this study were evaluated as adhesive material for cellulosic fibers by study the mechanical properties of the composite sheets .The results show that the substituting of (PF) with tannin at (10 –50)% W/W give resins with mechanical properties comparable or near to those of pure (PF) , where the tensile strength at break (Tb) ranging from 15.15 Mpa to 22.27 Mpa as compared with 17.6 Mpa for pure (PF); while the impact strength properties (Im) of composites sheets increased with increased the (T) percents which were about 5.16 KJ/m2 for (TPF – 10%) and 7.21 KJ/m2 for (TPF - 50%) .On the other hand modification of (T) to tannin formaldehyde resin (TF) appear less performance at the results of this study , this effect probably to low penetration of (TFPF) resins between the small voids of cellulose fibers when soaked it in resin solutions. In general the results of this study indicate that the Eucalyptus tannin can be used for par-tial substitution of (PF) to produce resins with feasible mechanical properties and can be used in some applications of (PF) resins.
Mode of travel and the decision to allow children to walk or bike to schools—The Abu Dhabi experience  [PDF]
Masood A. Badri, Abdulla M. Ustadi, Lynne Pierson, Mubarak Al Dramaki
Open Journal of Preventive Medicine (OJPM) , 2012, DOI: 10.4236/ojpm.2012.24071
Abstract: The study investigates school travel to and from schools as perceived by parents in Abu Dhabi, United Arab Emirates. Far fewer children are cycling or walking to school, and more and more are being driven to school by car. Traffic conditions, environmental factors, distance to school, road’s infrastructures, walking or biking with groups, schools efforts to educate children about active travel, and preferences of parents to accompany children to school were significantly perceived as important. The absence of active travel culture in the community was seen as a significant factor. Parent’s gender, child’s gender, child’s grade level, number of cars owned by the family, nationality and number of children were significantly associated with parents’ decisions to allow active travel to school. Results show that Abu Dhabi must establish aggressive strategic plans to promote active-commuting to school as the main mode of transportation. Current conditions in Abu Dhabi City are not conducive to active travel to school.
Simultaneous Tuning of Power System Stabilizers for Enhancing the Damping Performance in Multi-Machine Power Systems
A. Mahabuba,M. Abdullah Khan,Yousif Abdulla
International Journal of Electrical and Power Engineering , 2012, DOI: 10.3923/ijepe.2010.198.208
Abstract: This study presents a simultaneous tuning of Power System Stabilizers (PSS) for enhancing the damping of low frequency electro-mechanical oscillations in a multi-machine power system using parameter- constrained non-linear optimization algorithm. The main objective of this procedure is to shift the undamped poles to the left hand side of the s-plane. In the proposed study, the parameters of each PSS controller are determined simultaneously using non-linear optimization technique. The objective of the simultaneous parameter tuning is to globally optimize the overall system damping performance by maximize the damping of all both local and inter area modes of oscillations. The results obtained from simultaneous coordinating tuning method validate the improvement in damping of the overall power system oscillations in an optimal manner. The time domain simulation results of multi-machine power system validate the effectiveness of the proposed approach. In this study, 10-machine 39-bus New England system is used as the test system.
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