Isatin (1H-indole-2, 3-dione) and its analogs are an important class of heterocyclic compounds. N-benzyl isatins and Schiff bases of isatin analogs have been reported to demonstrate a variety of biological activities. This work illustrates the synthesis of new N-benzylisatin Schiff bases and studies their biological activity. Firstly, Isatin and its analogs; 5-methoxyisatin, 5-fluoroisatin reacted with benzyl iodide to obtain N-benzylated derivatives of isatins 2 (ac). Secondly, these compounds were reacted with different amines (sulphanilamide and 4-methyl sulphonyl aniline) separately, to obtain Schiff bases compounds 3 (ac) and 4 (ac), respectively. The synthesized compounds were characterized by using FT-IR and 1HNMR spectroscopy. The s
... Show MoreBootstrap is one of an important re-sampling technique which has given the attention of researches recently. The presence of outliers in the original data set may cause serious problem to the classical bootstrap when the percentage of outliers are higher than the original one. Many methods are proposed to overcome this problem such Dynamic Robust Bootstrap for LTS (DRBLTS) and Weighted Bootstrap with Probability (WBP). This paper try to show the accuracy of parameters estimation by comparison the results of both methods. The bias , MSE and RMSE are considered. The criterion of the accuracy is based on the RMSE value since the method that provide us RMSE value smaller than other is con
... Show MoreIn this study, crop residues from rice husks were used to enhance the properties of the prepared
wood-plastic composites (W.P.C) are made from epoxy (EP) and unsaturated polyester (UPE) at
a ratio of (50:50) and reinforced with scales in different proportions, both types are fine
(300μm≤) and coarse (300μm>). These blends were undergoing (wear, impact, hardness,
differential scanning calorimetry (DSC), and thermal conductivity) tests and the results showed
the best weight fraction. is the fine particle weight fraction at 25% and coarse at 15%, depending
on the studied tribological characteristics. The results showed by thermal properties of glass
transition temperatures (Tg). For each of the (EP,
This work includes the synthesis of new ester compounds containing two 1,3,4-oxadiazole rings, 15a-c and 16a-c. This was done over seven steps, starting with p-acetamido-phenol 1 and 2-mercaptobenzoimidazole 2. The structure of the products was determined using FT-IR, 1H NMR, and mass spectroscopy. The evaluation of the antimicrobial activities of some prepared compounds was achieved against four types of bacteria (two types of gram-positive bacteria; Staphylococcus aureus and Bacillus subtilis, and two types of gram-negative bacteria, Pseudomonas aeruginosa and E. Coli), as well as against one types of fungus (C. albino). The results show moderate activit against the study bacteria, and the theoretical analysis of the toxi
... Show MoreIn this work, Schiff base ligands L1: N, N-bis (2-hydroxy-1-naphthaldehyde) hydrazine, L2: N, N-bis (salicylidene) hydrazine, and L3:N –salicylidene- hydrazine were synthesized by condensation reaction. The prepared ligands were reacted with specific divalent metal ions such as (Mn2+, Fe2+, Ni2+) to prepare their complexes. The ligands and complexes were characterized by C.H.N, FT-IR, UV-Vis, solubility, melting point and magnetic susceptibility measurements. The results show that the ligands of complexes (Mn2+, Fe2+) have octahedral geometry while the ligands of complexes (Ni2+) have tetrahedral geometry.
The purpose of this article is to improve and minimize noise from the signal by studying wavelet transforms and showing how to use the most effective ones for processing and analysis. As both the Discrete Wavelet Transformation method was used, we will outline some transformation techniques along with the methodology for applying them to remove noise from the signal. Proceeds based on the threshold value and the threshold functions Lifting Transformation, Wavelet Transformation, and Packet Discrete Wavelet Transformation. Using AMSE, A comparison was made between them , and the best was selected. When the aforementioned techniques were applied to actual data that was represented by each of the prices, it became evident that the lift
... Show MoreThis research of the thesis includes the preparation and identification of two new tetra dentate Schiff's base ligand . (H4L1 ) and then binuclear complexes with a group of transition metal ions in addition to cadmium with the general formula. [M2(L1)Cl2(H2O)2] M+2=[Mn,Co,Ni,Cu and Cd] The prepared complexes and ligands were identified by in pared(FT-IR) spectroscopy ,Ultra violet-visible(UV-visible) spectroscopy and H-NMR spectroscopy of the prepared ligand, also microanalysis (C.H.N) of some of the prepared compounds has been carried out and the melting points, the molar conductivity and magnetic susceptibility
B3LYP density functional is utilized for probing the effect of decorating Al, Ga, and In on the sensing performance of a boron phosphide nanotube (BPNT) in detecting the 2-chloroethanol (CHE) molecule. We predict that the interaction of pure BPNT with CHE is physisorption, and the sensing response (SR) of BPNT is approximately 6.3. The adsorption energy of CHE is about − 26.3 to − 91.1, − 96.6, and − 100.3 kJ/mol, when the Al, Ga, and In metals are decorated on the BPNT surface, respectively. This indicates that the decorated metals significantly strength the interaction. Also, the corresponding SR meaningfully rises to 19.4, 41.0, and 93.4, indicating that by increasing the atomic number of metals, the sensitivity i
... Show MoreThe logistic regression model regarded as the important regression Models ,where of the most interesting subjects in recent studies due to taking character more advanced in the process of statistical analysis .
The ordinary estimating methods is failed in dealing with data that consist of the presence of outlier values and hence on the absence of such that have undesirable effect on the result. &nbs
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