Space time fractional KdV Burgers equation for dust acoustic shock waves in dusty plasma with non-thermal ions

The KdV–Burgers equation for dust acoustic waves in unmagnetized plasma having electrons, singly charged nonthermal ions, and hot and cold dust species is derived using the reductive perturbation method. The Boltzmann distribution is used for electrons in the presence of the cold(hot) dust viscosity coefficients. The semi-inverse method and Agrawal variational technique are applied to formulate the space–time fractional KdV–Burgers equation which is solved using the fractional sub-equation method. The effect of the fractional parameter on the behavior of the dust acoustic shock waves in the dusty plasma is investigated.     

Three-dimensional quantitative structure activity relationship (QSAR) of cytotoxic active 3,5-diaryl-4,5-dihydropyrazole analogs: a comparative molecular field analysis (CoMFA) revisited study

ABSTRACT: In vitro antitumor evaluation of the synthesized 46 compounds of 3,5-diaryl-4,5-dihydropyrazoles against EAC cell lines and 3D QSAR study using pharmacophore and Comparative Molecular Field Analysis (CoMFA) methods were described. CoMFA derived QSAR model shows a good conventional squared correlation coefficient r2 and cross validated correlation coefficient r2 cv 0.896 and 0.568 respectively. In this analysis steric and electrostatic field contribute to the QSAR equation by 70% and 30% respectively, suggesting that variation in biological activity of the compounds is dominated by differences in steric (van der Waals) interactions. To visualize the CoMFA steric and electrostatic field from partial least squares (PLS) analysis, contour maps are plotted as percentage contribution to the QSAR equation and are associated with the differences in biological activity. BACKGROUND: Pyrazole derivatives exhibit a wide range of biological properties including promising antitumor activity. Furthermore, Aldol condensation assisted organic synthesis has delivered rapid routes to N-containing heterocycles, including pyrazoles. Combining these features, the use of chalconisation-assisted processes will provide rapid access to a targeted dihydropyrazoles library bearing a hydrazino 3D QSAR study using pharmacophore and Comparative Molecular Field Analysis (CoMFA) methods were described for evaluation of antioxidant properties. RESULTS: Chalcones promoted 1 of the 2 steps in a rapid, convergent synthesis of a small library of hydrazinyl pyrazole derivatives, all of which exhibited significant antitumor activity against Ehrlich Ascites Carcinoma (EAC) human tumor cell line comparable to that of the natural anticancer doxorubicin, as a reference standard during this study. In order to understand the observed pharmacological properties, quantitative structure-activity relationship (3D QSAR) study was initiated. CONCLUSIONS: Chalcones heating provides a rapid and expedient route to a series of pyrazoles to investigate their chracterization scavenging properties. Given their favorable properties, in comparison with known anticancer, these pyrazole derivatives are promising leads for further development and optimization.     

Synthesis and antimicrobial evaluation of some pyrazole derivatives

Reaction of a series of (E)-3-phenyl-4-(p-substituted phenyl)-3-buten-2-ones with p-sulfamylphenyl hydrazine in glacial acetic acid gave the corresponding hydrazones, subsequent treatment of which with 30% HCl afforded pyrazole-1-sulphonamides. On the other hand, refluxing of chalcones with either thiosemicarbazide or isonicotinic acid hydrazide in ethanol containing a few drops of acetic acid gave pyrazoline-1-thiocarboxamides and isonicotinoyl pyrazolines, respectively. The structures of the synthesized compounds were determined on the basis of their elemental analyses and spectroscopic data. The antimicrobial activity of the newly isolated heterocyclic compounds was evaluated against Gram-positive, Gram-negative bacteria and fungi. Most of the compounds showed a moderate degree of potent antimicrobial activity.     

Mono- and penta-nuclear self-assembled silver(I) complexes of pyrazolyl s-triazine ligand; synthesis,structure and antimicrobial studies

The self-assembled [Ag (PTDM)NO₃] ( 1 ), [Ag (PTDM)₂(H₂O)]ClO₄^.H₂O ( 2 ) and [Ag₅(PTDM)₄(H₂O)₆(ClO₄)₄]ClO₄^.2H₂O ( 3 ) complexes were synthesized by the direct mixing of AgX (X = NO₃¯ or ClO₄¯) and 4,4′-[6-(3,5-dimethyl-1H-pyrazol-1-yl)-1,3,5-triazine-2,4-diyl]dimorpholine ( PTDM ) ligand in water–methanol mixture. The coordination numbers of silver range from three to five. Complex 3 is a rare case in which one nitrogen atom from the same s-triazine core of the PTDM ligand has a μ(1,1) bridging mode between Ag1 and Ag2 in the penta-nuclear array with Ag1–N1 and Ag2–N1 distances of 2.666(4) and 2.418(3) Å, respectively. Its 3D topology has a kind of primitive dense packing derived from the α-Po type structure. Hirshfeld analysis showed that the percentages of the O^…H hydrogen bonds were 32.4, 25.4, and 42.0% in complexes 1 – 3 , respectively. While the ligand showed no antimicrobial activity at the applicable concentration, the penta-nuclear complex 3 had higher antibacterial (MIC = 3.7 μmol/L) and antifungal (14.6 μmol/L) potencies toward the tested microbes compared with complexes 1 and 2 . Also, the killing doses of 3 were in the range of 7.3–58.5 μmol/L compared with 18.2–291.1 and 20.1–160.6 μmol/L for 1 and 2 , respectively. It is clear that the higher Ag-content in 3 could be the main reason for its higher antimicrobial activity.     

Adsorptive characteristics of some metal ions on chitosan/zirconium phosphate/silica decorated graphene oxide

Journal of Radioanalytical and Nuclear Chemistry - Graphene oxide/chitosan/zirconiumphosphate/silicate (GO/CS/ZrP/Si) as a novel nano-composite has highly adsorption of 134Cs, 60Co, 152, 154Eu and...     

Synthesis and spectral characterization of some new N-substituted 2-aminobenzothiazoles, 2-aminothiazolopyridines and 2-aminothiazoloquinolines

A series of N-substituted 2-aminobenzothiazoles, 2-aminothiazolopyridines, and 2-aminothiazoloquinolines were prepared by the cyclization of N,N'-disubstituted thiourea derivatives by bromine in acetic acid. The uv, ir and nmr data for these compounds are presented and discussed.     

Then-component cubic model and flows: Subgraph break-collapse method

We specialize to then-component cubic model the subgraph break-collapse method which we recently developed for theZ() model. The cubic model has less symmetry than the Potts model, for which the method was originally developed, but nevertheless it is still possible to reduce considerably the computational complexity of the generalZ() model. Our recursive algorithm is similar, forn=2, to the break-collapse method for theZ(4) model proposed by Mariz and co-workers. It allows the exact calculation for the partition function and correlation functions forn-component cubic clusters, withn as a variable, without the need to examine all of the spin configurations. An important application is therefore in real-space renormalization-group calculations.     

The (4,0) mode of HF dimer at 14,700 cm(-l)

The deltaK = 0 and 1 subbands of the (4,0) <-- (0,0) transition of (HF)2, near 14,700 cm(-1), have been measured by molecular-beam intracavity laser-induced fluorescence. The hydrogen interchange tunneling is basically quenched in (4, 0) for both K = 0 and 1 levels, consistent with the early suggestion from a phenomenological model [H.-C. Chang and W. Klemperer, J. Chem. Phys. 104, 7830 (1996)]. The band origin upsilon0 = 14,700.458(7) cm(-1) and rotational constant (B + C)/2 = 0.22278(31) cm(-1) are determined for K = 0 of the (4, 0) mode. From the observed deltaK = 1 <-- 0 spectrum, we determined that A = 24.3 cm(-1), (B + C)/2 = 0.22296(20) cm(-1), and (B-C) = 4.5(2) x 10(-3) cm(-1). The predissociation linewidths of both K = 0 and 1 levels are 470(30) MHz with no apparent rotational dependence.     

New Polymer Syntheses Part 60: A Facile Synthetic Route to Polyamides Based on Thieno[2,3-b]thiophene and Their Corrosion Inhibition Behavior

Polyamides containing thieno[2,3-b]thiophene moiety were prepared via a simple polycondensation reaction of the diaminothieno[2,3-b]thiophene monomer 1 a with different kinds of diacid chlorides(including oxalyl, adipoyl, sebacoyl, isophthaloyl,terephthaloyl, 4,4′-azodibenzoyl, 3,3′-azodibenzoyl, p-phenylene diacryloyl) in the presence of Li Cl and NMP as a solvent through lowtemperature solution polycondensation. The chemical structures of model compound and synthesized polyamides were confirmed by FTIR, nuclear magnetic resonance spectroscopy(including ~1H-NMR and ~(13)C-NMR) and elemental analysis. In addition, the thermal stability, crystallinity structure and surface morphology of synthesized polyamides were characterized via thermogravametric analysis(TGA), wide-angle X-ray diffraction analysis(WAXD) and scanning electron microscopy(SEM). Also, the corrosion inhibition behavior of selected examples of polyamides was investigated; the inhibitive effect of the investigated polymers for carbon steel in 1.0 mol·L~(-1) HCl was studied using potentiodynamic polarization(PDP) and electrochemical impedance spectroscopy(EIS) methods. PDP results displayed that the polyamides containing thieno[2,3-b]thiophene moiety can be as mixed-type inhibitors. The inhibition efficiency(P, %) was found to be in the range from 67.13% to 96.01%. There is an increase in P by the synthesized polymers in comparison to the starting monomer.The adsorption of these polymers was found to obey Langmuir adsorption isotherm.