ZnS nanoparticles were prepared by a simple microwave irradiation method under mild condition. The starting materials for the synthesis of ZnS quantum dots were zinc acetate (R & M Chemical) as zinc source, thioacetamide as a sulfur source and ethylene glycol as a solvent. All chemicals were analytical grade products and used without further purification. The quantum dots of ZnS with cubic structure were characterized by X-ray powder diffraction (XRD), the morphology of the film is seen by scanning electron microscopy (SEM). The particle size is determined by field effect scanning electron microscopy (FESEM), UV-Visible absorption spectroscopy and XRD. UV-Visible absorption spectroscopy analysis shows that the absorption peak of the as-prepared ZnS sample (310 nm) displays a blue-shift comparing to the bulk ZnS (345 nm). Photoluminescence spectra of the samples revealed a broad peak centered at 404nm, which were related to excitonic emission. Photocatalytic degradation of Methylene Blue (MB) dye catalyzed by synthesized nanoparticles was studied under solar radiation, photocatalytic degradation increased with increasing time exposure to solar light.
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The present paper investigates the role of fear and predator dependent refuge in the prey-predator system. The system describes the interaction between prey and a stage structure of predator that incorporates Holling II functional response. The predator splits into two compartments immature (juvenile) and mature (adult). The mature predators can hunt and reproduce but this capability is not found in the immature predators, the immature depend on their parents. The growth rate of prey decreases due to the existence of mature predators. The existence, uniqueness, and boundedness of the solution of the system are investigated. Three equilibrium points of the system are determined. The local stability of the system is studied. The global stabil
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The effect of heat treatment on the optical properties of the bulk heterojunction blend nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt and Tris (8-hydroxyquinolinato) Aluminum (NiPcTs/Alq3) thin films which prepared by spin coating was described in this study. The films coated on a glass substrate with speed of 1500 rpm for 1.5 min and treated with different annealing temperature (373, 423 and 473) K. The samples characterized using UV-Vis, X ray diffraction and Fourier transform Infrared (FTIR) spectra, XRD patterns indicated the presence of amorphous and polycrystalline blend (NiPcTs/Alq3). The results of UV visible shows that the band gap increase with increasing the annealing temperature up to 373 K and decreases with
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Polyaniline Multi walled Carbon nanotubes (PANI/MWCNTs) nanocomposite thin films have been prepared by non-equilibrium atmospheric pressure plasma jet on glass substrate with different weight percentage of MWCNTs 1, 2, 3, 4%. The diameter of the MWCNTs was in the range of 8-55 nm and length - - 55 55 μm. the nanocomposite thin films were characterized by UV-VIS, XRD, FTIR, and SEM. The optical studies show that the energy band gap of PANI/MWCNTs nanocomposites thin films will be different according to the MWCNTs polyaniline concentration. The XRD pattern indicates that the synthesized PANI/MWCNTs nanocomposite is amorphous. FTIR reveals the presence of MWCNTs nanoparticle embedded into polyaniline. SEM surface images show that the MWCNT
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The determiner phrase is a syntactic category that appears inside the noun phrase and makes it definite or indefinite or quantifies it. The present study has found wide parametric differences between the English and Arabic determiner phrases in terms of the inflectional features, the syntactic distribution of determiners and the word order of the determiner phrase itself. In English, the determiner phrase generally precedes the head noun or its premodifying adjectival phrase, with very few exceptions where some determiners may appear after the head noun. In Arabic, parts of the determiner phrase precede the head noun and parts of it must appear after the head noun or after its postmodifying adjectival phrase creating a discontinu
... Show MoreA descriptive evaluation study is conducted on primary health care centers in Baghdad City in order to
evaluate the organization structure as component of quality improvement of maternal and child health promotion
from April 10th 2012 to May20th 2013. A total of (22) primary health care centers. Study instrument was
comprised of three questionnaires and overall items included in these questionnaire were (65) items. Data are
collected through the utilization of the developed questionnaire and the interview technique as means of data
collection. Data are analyzed through the application of descriptive statistical data analysis methods which
includes the measurement of the frequencies, percentages, and computation of mean
Abstract
The target derivative are gentamicin linked with L-Val- L-Ala by an ester linkage. These were synthesized by esterification method, which included the reaction of -OH hydroxyl group on (carbon No.5) of gentamicin with the acid chloride of the corresponding dipeptide, The preparation of new derivative of gentamicin involved protected the primary & secondary amine groups of Gentamicin, by Ethylchloroformate (ECF) to give N-carbomethoxy Gentamicin which was used for further chemical synthesis involving the free hydroxyl groups.
Then prepared dipeptide (L-Val- L-Ala) by conventional solution method in present DCC & HoBt then reacted with thionyl
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Means the current research to study the organization formal and its role in demonstrating aesthetic values of the publications issued by the Telecommunications Company (Asia Cell) in Iraq, where is the organization the formal need for a mission to find the concepts and dimensions of the functional and expressive and aesthetic added to the impact of the actor in achieving the goals set for the publication.
The target is determined by the researcher to disclose the role of formal organization to show the aesthetic values of the publication to reach scientific results
Ön söz
Büyük dil bilgini Kaşgarlı Mahmud’un Divan-ı Lugat-it Türk isimli muazzam eseri, 1910’a kadar adı bilinen, fakat kendisi meçhul bir eserdi. Diğer bir deyişle, o zamana değin, eserin sadece adı vardı, fakat kendisi ortada yoktu. Eser, bugün bütün dünyada biliniyor, hakkında kitap, makale yazılıyor ve üzerinde tartışmalar yapılıyorsa, bunu büyük kitap aşığı, ilim ve kültür sevdalısı Ali Emiri Efendi’ye borçluyuz. Ali Emiri Efendi, Abbasi Halifesine sunulmak üzere Bağdat’ta 1072-1074 yıllarında Kaşgarlı Mahmud tarafından yazılan bu muhteşem eseri, sahaflarda Divan-ı Lugat-it Türk olduğu bilinmeden satılı
... Show MoreIn this work, ZnO quantum dots (Q.dots) and nanorods were prepared. ZnO quantum dots were prepared by self-assembly method of zinc acetate solution with KOH solution, while ZnO nanorods were prepared by hydrothermal method of zinc nitrate hexahydrate Zn (NO3)2.6H2O with hexamethy lenetetramin (HMT) C6H12N4. The optical , structural and spectroscopic properties of the product quantum dot were studied. The results show the dependence of the optical properties on the crystal dimension and the formation of the trap states in the energy band gap. The deep levels emission was studied for n-ZnO and p-ZnO. The preparation ZnO nanorods show semiconductor behavior of p-type, which is a difficult process by doping because native defects.