Piezoelectric structures are nowadays used in many different applications. A better understanding of the influence of material properties and geometrical design on the performance of these structures helps to develop piezoelectric structures specifically designed for their application. Different equivalent circuits have been introduced in the literature to investigate the behaviour of piezoelectric transducers. The model parameters are usually determined from measurements covering the characteristic frequencies of the piezoelectric transducer. This article introduces an analytical technique for calculating the mechanical and electrical equivalent system parameters and characteristic frequencies based on material properties and geometry for a cantilever bimorph structure. The model is validated by measurements using a cantilever bimorph and fits the experimental results better than previous models. The model gives a full set of piezoelectric transducer parameters and is therefore well suited for further theoretical investigations of piezoelectric transducers for different applications. The results also show that even small manufacturing tolerances have a considerable effect on the system parameters and characteristic frequencies. This might lead to intolerable deviations, especially in dynamic applications and should be avoided by careful design and production.
Results of charge, neutron and matter densities and related form factors for one- proton halo nucleus 8B are presented using a two- frequency shell model approach. We choose a model space for the core of 7Be different from that of the extra one valence proton. One configuration is assumed for the outer proton to be in 1p1/2 - shell. The results of the matter density distributions are compared with those fitted to the experimental data. The calculated proton and matter density distributions of this exotic nucleus exhibit a long tail behavior, which is considered as a distinctive feature of halo nuclei. Elastic electron scattering form factors of this exotic nucleus are also studied. The effects of
... Show MoreThe concept of clarity and readability of the written texts is an important goal in order to convey the communication idea to the receiver easily; the written texts have special significance because it is the most effective way to fulfill this idea as well as to achieve the aesthetic dimension of the written material, and clarity in the written texts is a prerequisite for reading, and readability is the speed of the optical reading of the written form, as the letters design plays a key role in facilitating the readability of the texts, and thus, it is necessitated to take care of these texts and studied them thoroughly in terms of shape for easy to read, and thus to understand the implications of the texts.
For that reason, the resear
Precision is one of the main elements that control the quality of a geodetic network, which defines as the measure of the network efficiency in propagation of random errors. This research aims to solve ZOD and FOD problems for a geodetic network using Rosenbrock Method to optimize the geodetic networks by using MATLAB programming language, to find the optimal design of geodetic network with high precision. ZOD problem was applied to a case study network consists of 19 points and 58 designed distances with a priori deviation equal to 5mm, to determine the best points in the network to consider as control points. The results showed that P55 and P73 having the minimum ellipse of error and considered as control points. FOD problem was applie
... Show MoreBackground: To test effectiveness and safety of topical methotrexate 0.5%gel and to introduce new formula of methotrexate gel using suitable media for delivery.
Patients and Methods: The clinical work was performed at the Department of Dermatology and Venereology in Baghdad Teaching Hospital during the period from January 2008 to October 2008. While preparation of formula was performed in the laboratories of the Department of Pharmacology- College of Medicine-University of Baghdad. Patients were divided in to two groups according to the type of treatment, group (I) 32 patients treated with methotrexate 0.5% gel and group(II) (placebo group) included 33 patients treated with placebo gel.
Results: A tota
Many biochemical and physiological properties depend on the size of ions and the thermodynamic quantities of ion hydration. The diffusion coefficient (D) of lanthanide (III) ions (Ln+3) in solution assumed (1.558-1.618 ×10−9 m2 s−1) by Einstein–Smoluchowski relation. The association constant (KA) of Ln+3 ions was calculated (210.3-215.3 dm3 mole-1) using the Shedlovsky method, and the hydrodynamic radius calculated (1.515-1.569 ×10−10 m) by the Stokes-Einstein equation. The thermodynamic parameters (ΔGo, ΔSo) also calculated by used suitable relations, while ΔHo, values are obtained from the lit
... Show MoreThe research presented the tagged (aesthetic and expressive characteristics in the works of Jean Dubuffet), so the research objective was: to know the aesthetic and expressive characteristics in the works of (Jean Dubuffet), and the research included four chapters. The aim of the research, the limits of the research, and the definition of terms. The second chapter included four topics. The first topic presented the aesthetic essence and style, while the second topic dealt with expressionism: approaches in concept and meaning.
While the third topic was preoccupied with presenting the aesthetic and expressiveness in the drawings of modernity and beyond, while the fourth topic dealt with: Jean Dubuffet and the experience of raw art. Th
In this work 2-mercaptobenzoxazole (2-MBO) (1), was prepared by using homemade Auto clave .The synthesis involve treatment of 2-MBO with 2-chloro acetyl chloride to give 2-chloroacetyl thio benzoxazole (2), the product was treated with phenyl hydrazine to give 2-phenyl hydrazide acetyl thio benzoxazole (3). The new derivatives (4-13) were synthesized by reaction of 2-phenyl hydrazide acetyl thio benzoxazole (3) with different aromatic aldehydes in the presence of acetic acid. The compound (2) was treated with hydrazine hydrate to give product (14) then treated with different aromatic aldehydes in the presence of glacial acetic acid to give Schiff bases derivatives (15-24). Structure of all the prepared compounds confirmation were proved
... Show MoreOverall enthalpy and entropy of complex formation were calculated from stability constant measurements at different tempreture also experimental results
Recent progress in the understanding of psoriasis has shown that the regulation of local and systemic cytokines plays an important role in its pathogenesis. Different studies evaluated the association of serum levels of some proinflammatory cytokines invivo and their correlation with severity of psoriasis. Eighty cases of psoriatic patients had been studied. Patients were divided into mild psoriasis group (30) and severe psoriasis group (50) according to severity, and (30) apparently healthy individuals ware used as acontrol group. Sera samples of all groups were collected from all individuals for the estimation levels of interleukins (IL-6 and IL-8). All mean values sera levels (IL-6 32.004 pg/ml and 17.579 pg/ml for
... Show MoreA local isolate Bacillus subtilis was used, which producing
thennophilic complex enzyme having similar activity of endogluganase
enzyme ( Endo-l,4-B-Dglucanase ).
Partially digested chromosomal DNA of Bacillus subtilis by Eco
Rl restriction enzyme randomly cloned into Eco Rl pSU10l shuttle vector. The resulted hybrid plasmid was transformed into protoplast of
Streptomyces sp. SH-H.
The result revealed  
... Show More