Four novel Schiff bases SB1 to SB4 as new aromatic compound not hydrolysed under ordinary conditions were synthesized in this study by condensation reactions between2,4dinitrophenylhydrazine: firstly with 2,4,4`-trihydroxybenzophenone to give SB1, secondly with 4hydroxybenzophenone to give SB2, thirdly with 4-dimethylaminobenzaldhyde to give SB3 and fourthly with 4-aminobenzaldehyde to give SB4. The molecular structures of these aromatic Schiff bases obtained were identified and characterized based on melting points, elemental analysis(CHN), FT-IR and UV-Visible spectra. The electronic absorption spectra of Schiff bases obtained were studied in the solvents of ethanol, DMF, water, chloroform, carbon tetrachloride and cyclohexane. The recorded absorption bands in ethanol solvent were assigned to corresponding electronic transitions were discussed. The absorption bands at 291 to 411 nm obtained in electronic spectra of the synthesized new aromatic Schiff bases were assigned to (π→π*) transition which originates from substituted benzophenone or benzaldehyde rings and directed along of molecule in Schiff bases. These transitions are assumed to represent the intramolecular charge-transfer complexes bands in which the substituted two moieties of benzophenone and benzaldehyde rings are the charge donors and the substituted phenylhydrazine ring is the charge acceptor. Also, the effect of polar, non-polar solvents on the electronic transitions of charge-transfer bands have measured and discussed. The physical-spectroscopic parameters in molecular structural shapes of intra CT complexes molecules such as transition energies, molar extinction coefficients, molecular oscillate strength; transition molecular dipole moment and molecular resonance have been calculated and discussed.
In this paper , two method which deal with finding the optimal value for adaptive smoothing constant, are compared .This constant is used in adaptive Single Exponential Smoothing (ASES).
The comparing is between a method uses time domain and another uses frequency domain when the data contain outlier value for autoregressive model of order one AR(1) , or Markov Model, when the time series are stationary and non stationary with deferent samples .
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X-ray phase analysis was used to analyse the composition of Pb8Na(2±x)(PO4)6 (lead-sodium apatite structure) with different X values (X values refer to changes in the excess or lack of sodium (2±X) in the apatite structure): -0.15, -0.10, -0.05, 0.00, +0.05, +0.10, and +0.15. The ceramic method (solid-state reaction) was used to synthesize all samples at a temperature of 800 °C. Many programs, such as match software (v.3), PDF-4 database (ICCD), and database PDF-4 (ASTM), were used to study the single phases. The least-squares method was used to calculate the unit cell parameters. Results have shown that the following compositions: Pb8Na2(PO4)6<
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In the present study a new synthesis method has been introduced for the decoration of platinum(Pt) on the functionalized graphene nanoplatelet (GNP) and also highlighted the preparation method of nanofluids. GNP–Pt uniform nanocomposite was produced from a simple chemical reaction procedure, which included acid treatment for functionalization of GNP. The surface characterization was performed by various techniques such as XRD, FESEMand TEM. The effective thermal conductivity, density, viscosity, specific heat capacity and stability of functionalized GNP–Pt water based nanofluids were investigated in different instruments. The GNP–Pt hybrid nanofluids were prepared by dispersing the nanocomposite in base fluid without adding any surfac
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A series of 1,3-diarylprop-2-en-1-one oximes (7-12) were synthesized via reaction of 1,3-diarylprop-2-en-1-one (1-6) with NH2OH. HCl in dry pyridine. In order to produce the required products (13-18) as anti-isomers, these products (7–12) were then treated with acetic anhydride in dry pyridine. Different substitutes are maintained, resulting in the separation of different products in different yields The recently produced esters are thought to be useful as building blocks for the synthesis of substituted pyridines and many other nitrogen-holding complexes, which are elaborate structures in medicinal chemistry and present in a variety of pharmaceutical medications. The synthesized products were characteriz
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The present study was carried to evaluate antibacterial activity of Acetone, Alcholic (cold and hot) and Aqueaus(water) extracts of Citrus aurantifoliaseeds,against growth of some bacteria isolated from burns infections(Pseudomonas aeruginosa,Escherichia coli, Klebsiellapneumonia,Staphylococcusaureus)fromKindy HospitalIn Baghdad from March to June 2012.Antibiotic Sensitivity was done for all isolated bacteria used in this study.Results showed variation in antibacterial activity of different extracts against all tested bacteria by well diffusion technique in agar and measuring the diameter of inhibition zone, at concentration 250Mg-ml. Acetone extract had the greatest inhibitory effect followed by hot alcoholci extract, and then cold alcohol
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In this paper, a description of a design for new DES block cipher, namely DES64X and DES128X. The goals of this design, a part of its security level, are large implementation flexibility on various operating systems as well as high performances. The high level structure is based on the principle of DES and Feistel schema, and proposes the design of an efficient key-schedule algorithm which will output pseudorandomsequences of subkeys. The main goal is to reach the highest possible flexibility, in terms of round numbers, key size, and block size. A comparison of the proposed systems on 32-bit, 64-bit operating system, using 32-bit and 64-bit Java Virtual Machine (JVM), showed that the latter has much better performance than the former.
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This paper considers and proposes new estimators that depend on the sample and on prior information in the case that they either are equally or are not equally important in the model. The prior information is described as linear stochastic restrictions. We study the properties and the performances of these estimators compared to other common estimators using the mean squared error as a criterion for the goodness of fit. A numerical example and a simulation study are proposed to explain the performance of the estimators.
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