Explosives detection with electron‐rich polymers

The application of polymeric films as alarms for explosive materials is a critical issue these days as mandated by homeland security requirements. Amongst the multiple advantageous points of applying polymer films in this area is the fact that they are cheap material, so they can be applied on a broad scale for low cost. The basic idea of the current work is based on the fact that common explosives are electron deficient because of the existence of the nitro‐groups in their chemical structures, and this causes their high affinities towards electron rich materials to form charge‐transfer complex. Our endeavor is to trace any charge‐transfer complex formation, which would definitely cause a recognizable change in their physical properties. These changes in the polymers' physical properties could be utilized as alerts for the existence of explosive materials, especially if such changes could be incorporated into sophisticated electronic circuits that would give strong for traces of explosives. Copyright © 2013 John Wiley & Sons, Ltd.     

一些含三氮杂茂偶氮染料O,N供体的Zr(Ⅱ)配合物的合成、表征和抗微生物活性(英文)

合成了9种3-(2-羟基萘基-1-偶氮)-1,2,4-三氮唑(HL1),3-(2,4-二羟苯基-1-偶氮)-1,2,4-三氮唑(HL2),3-(2-羟基-3-羧基萘基-1-偶氮)-1,2,4-三氮唑(HL3),3-(2-羟基-5-溴苯基-1-偶氮)-1,2,4-三氮唑(HL4)和3-(2-羟基-5-甲基苯基-1-偶氮)-1,2,4-1,2,4-三氮唑(HL5)的Zr(Ⅱ)配合物并用元素分析,摩尔电导,磁矩,IR,UV-Vis,1H-NMR以及热分析(TGA和DTA)对其进行了表征。结果表明HL1-HL5以二齿一元配体方式通过偶氮的氮原子和羟基基团的氧原子与Zr(Ⅱ)离子配位生成单核配合物。用4种革兰氏阴性菌,即大肠杆菌(Escherichia coli),粘质沙雷氏菌(Serratia marcescens),阴沟肠杆菌(Enterobacter cloacae)和普通变形杆菌(Proteus vulgaris),以及2种真菌,即白色念珠菌(Candida albicans)和黑曲霉菌(Aspergillus niger)对配体及其配合物的生物学活性进行了研究。最小抑菌浓度(MICs)用纸上杯碟琼脂扩散法测定,结果表明在大多数情况下,金属化的配合物的抗微生物活性与自由配体相比有所增强。     

Investigation of 3-amino-1,2,4-triazole azodye derivatives as reagents for determination of mercury(II)

The reaction of mercury(II) with 3-(2,4-dihydroxyphen-1-ylazo)-1,2,4-triazole (HL¹), 3-(2-hydroxy-5-methylphen-1-ylazo)-1,2,4-triazole (HL²), 3-(2-hydroxy-5-ethoxycarbonylphen-1-ylazo)-1,2,4-triazole (HL³), 3-(2-hydroxy-5-acetylphen-1-ylazo)-1,2,4-triazole (HL⁴), 3-(2-hydroxy-5-formylphen-1-ylazo)-1,2,4-triazole (HL⁵), and 3-(2-hydroxy-5-bromophen-1-ylazo)-1,2,4-triazole (HL⁶) was studied. A new, direct, and simple procedure was suggested for the spectrophotometric determination of mercury(II) based on its complexation reaction with HL¹-HL⁶. The best reagent was found to be HL³ due to its high sensitivity and selectivity. In aqueous media of pH 9.0 containing 40 vol. % of methanol, Hg(II) reacts with HL³ to form a 1:2 (Hg(II) · HL³) complex having a sensitive absorption peak at 490 nm with the molar extinction coefficient of 3.31 × 10⁴ L mol⁻¹ cm⁻¹ using 4 × 10⁻⁴ M of the reagent. Beer’s law is obeyed over the range from 0.00 μg mL⁻¹ to 12.04 μg mL⁻¹ of mercury(II). The proposed method was applied in the determination of mercury(II) in tap water, seawater and synthetic seawater samples, without the need of prior treatment, with satisfactory results.     

The potential use of plume imaging for real-time monitoring of laser ablation cleaning of stonework

In this work, the potential of plume imaging was investigated as a real-time monitoring technique for the control of the laser cleaning process in cultural heritage objects with emphasis on encrusted stonework. Optical pulses generated by Nd:YAG laser were used to remove a high absorbing layer of crust from the surface of a lower absorbing marble substrate. Two regimes of operation have been employed for laser cleaning test, Q-switched ns mode, and short free running μs mode. Laser induced breakdown spectroscopy (LIBS) was also employed to study the stratigraphy of the cleaned surfaces, and thus to confirm the validity of the suggested monitoring technique. The tests proved the prospective of introducing plume imaging techniques as a straightforward and inexpensive tool for the real-time monitoring of laser ablation and the determination of the critical point for a safe surface cleaning intervention.     

Synthesis, molecular docking and preliminary in-vitro cytotoxic evaluation of some substituted tetrahydro-naphthalene (2',3',4',6'-tetra-O-acetyl-β-D-gluco/-galactopyranosyl) derivatives

A facile, convenient and high yielding synthesis of novel S-glycosides and N-glycosides incorporating 1,2,3,4-tetrahydronaphthalene and or 1,2-dihydropyridines moieties has been described. The aglycons 2, 4, and 7 were coupled with different activated halosugars in the presence of basic and acidic medium. The preliminary in-vitro cytotoxic evaluation revealed that compounds 3c, 3f, 5c and 7b show promising activity. A molecular docking study was performed against tyrosine kinase (TK) (PDB code: 1t46) by Autodock Vina. The docking output was analyzed and some compounds have shown hydrogen bond (H-B) formation with reasonable distances ranged from 2.06 A° to 3.06 A° with Thr 670 and Cys 673 residues found in the specified pocket. No hydrogen bond was observed with either Glu 640 nor Asp 810 residues, as was expected from pdbsum.     

Critical parameters of hard-core Yukawa fluids within the structural theory

A purely statistical mechanical approach is proposed to account for the liquid–vapor critical point based on the mean density approximation (MDA) of the direct correlation function. The application to hard-core Yukawa (HCY) fluids facilitates the use of the series mean spherical approximation (SMSA). The location of the critical parameters for HCY fluid with variable intermolecular range is accurately calculated. Good agreement is observed with computer simulation results and with the inverse temperature expansion (ITE) predictions. The influence of the potential range on the critical parameters is demonstrated and the universality of the critical compressibility ratio is discussed. The behavior of the isochoric and isobaric heat capacities along the equilibrium line and the near vicinity of the critical point is discussed in details.     

Pairwise weakly and pairwise strongly irresolute functions

In this paper we consider a new weak and strong forms of irresolute functions in bitopological spaces, namely, ij-quasi-irresolute functions and strongly irresolute functions. Several characterizations and basic properties of these functions are given. We investigate the relationships among some weak forms of continuity and other generalizations of continuous mappings in bitopological spaces.     

UV-vis, IR and (1)H NMR spectroscopic studies of some Schiff bases derivatives of 4-aminoantipyrine

Five Schiff bases derived from 4-aminoantipyrine and benzaldehyde derivatives (I) are prepared and their UV-vis, IR, (1)H NMR and fluorescence spectra are investigated and discussed. The electronic absorption spectra of the hydroxy 4-aminoantipyrine Schiff bases Ib and Ie as well as the fluorescence spectra of Ie are studied in the organic solvents of different polarity. The UV-vis absorption spectra of 4-aminoantipyrine Schiff bases Ib, Id and Ie are investigated in aqueous buffer solutions of varying pH and utilized for the determination of pK(a) and DeltaG of the ionization process. The reactions of the hydroxy compounds Ib and Ie with Ni(II) and Cu(II) ions are also studied. The results of spectral studies are supported by some molecular orbital calculations using an atom superposition and electron delocalization molecular orbital theory for a compound Ib.     

Liquid chromatographic method for the analysis of buspirone HCl and its potential impurities

An accurate, reproducible, and sensitive method for the determination of buspirone HCl and its potential impurities is developed and validated. The validated liquid chromaography method is conducted to meet the Food and Drug Administration/ International Conference on Harmonization requirements for the analysis of buspirone HCI in the presence of its impurities. Five buspirone HCI potential impurities, including 1-(2-pyrimidinyl)-piperazine (I), propargyl chloride (II), 3,3'-tetramethylene glutarimide (III), propargyl glutarimide (IV), and the Mannich base-condensate of I-IV fumarate (V), are separated using a microBondapack C18 column by gradient elution with a flow rate 2.0 mL/min. The initial mobile phase composition is 90:10 (v/v) 10mM KH2PO4 (pH 6.1)-acetonitrile. After a 1-min initial hold, a linear gradient is performed in 26 min to 35:65 (v/v) 10mM KH2PO4 (pH 6.1)-acetonitrile. The samples are detected at 210 and 240 nm using a photo-diode array detector. The linear range of detection for buspirone HCI was between 1.25 ng/microL and 500 ng/microL, with a limit of quantification of 1.25 ng/microL. The linearity, range, peak purity, selectivity, system performance parameters, precision, accuracy, and robustness for all of the impurities were also shown to have acceptable values.     

Elaborated spectral,modeling, QSAR,docking, thermal,antimicrobial and anticancer activity studies for new nanosized metal ion complexes derived from sulfamerazine azodye

New azodye ligand (H₂L) and its relative Cr(III)-, Mn(II)-, Fe(III)-, Co(II)-, Ni(II)-, Cu(II)-, Zn(II)- and Cd(II)-nanosized complexes were prepared. A new synthesized compounds were characterized using spectral (mass, IR, UV–Vis, XRD, and ESR) and analytical (elemental, molar conductance, thermal and magnetic moment measurements) tools. Infrared spectra showed that the ligand behaves as a monobasic bidentate, coordinating with central atoms through carbonyl oxygen and α-hydroxyl group. The geometrical structures of Cr(III) and Fe(III) complexes were found to be in octahedral configuration, whereas Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes have tetrahedral forms. XRD patterns reflect an amorphous appearance of all investigated complexes. TEM images showed nanosized particles and identical distribution over the complex surface. Molecular modeling for the drug ligand and its metal ion complexes were performed using Gaussian09 program to assert on their structural formulae. Some essential parameters were extracted using HOMO and LUMO energies. AutoDock tools 4.2 was used to simulate the interaction process with infected cell proteins to expect the experimental pathway. The inhibition activity of drug ligand and its metal ion complexes was evaluated towards different types of bacteria and fungi through in vitro antimicrobial activities. The antitumor activities of all compounds are straightened towards human liver carcinoma (HEPG2) cell lines. Fe(III) and Co(II) complexes exhibited IC₅₀ of 2.90 and 4.23 µg mL^?1, respectively, which means they are more potent anticancer drug than the standard (doxorubicin, IC₅₀ = 4.73 µg mL^?1). Therefore, the two complexes may consider promising anticancer drugs.