In this article, the effect of carbon nanotube’s (CNT) surface modification on mechanical, thermal, and morphological properties of nanocomposite with different content of CNTs was studied. CNT/high-density polyethylene (HDPE) nanocomposites were prepared by a mini twin-screw extruder. To modify the dispersion of MWCNTs in HDPE, the surface of CNTs was functionalized by HNO3 and stearic acid (SA). The tensile tests results show that addition of 5% of acid-treated CNT in HDPE cause to increase in Young’s modulus and yield strength up to 4% and 6%, respectively; as compared to unmodified CNT/HDPE nanocomposite. The presence of the SA on CNTs can lead to slight decrease of the CNT-SA/HDPE strength properties; when compared to pure CNT/PE nanocomposite. However, there is a fracture toughness enhancement in CNT-SA/HDPE up to 10% compare to unmodified CNT/PE nanocomposite. Furthermore, the calculation of the stress whitening zone of all samples verifies the fracture toughness data of CNT/HDPE nanocomposites. Scanning electron microscopic images showed that the best dispersion of CNTs in the HDPE matrix was seen in CNT-SA/HDPE nanocomposite.

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Thallium and its compounds are a class of highly toxic chemicals that cause wide-ranging symptoms such as gastrointestinal disturbances; polyneuritis; encephalopathy; tachycardia; skin eruptions; hepatic, renal, cardiac, and neurological toxicities; and have mutagenic and genotoxic effects. The present research aimed to evaluate the efficacy of the chelating agents deferasirox (DFX) and deferiprone (L1) in reducing serum and tissue thallium levels after the administration of thallium (III), according to two different dosing regimens, to several groups of Wistar rats for 60 days. It was hypothesized that the two chelators might be more efficient as a combined therapy than as monotherapies in removing thallium (III) from the rats’ organs. The chelators were administered orally as either single or combined therapies for a period of 14 days. Serum and tissue thallium (III) and iron concentrations were determined by flame atomic absorption spectroscopy. Serum and tissue thallium (III) levels were significantly reduced by combined therapy with DFX and L1. Additionally, iron concentrations returned to normal levels and symptoms of toxicity decreased.

A series of 23 novel phosphorhydrazide derivatives were synthesized and characterized by spectral techniques, and their anti-ChE, antibacterial and insecticide activities were investigated.

For the first time, the thermal decomposition behavior of heterogeneous mixtures of ammonium perchlorate (AP) with two organic additives – 4, 4’‐Bipyridine, and biphenyl – were investigated. The heterogeneous mixtures of the additives and ammonium perchlorate were prepared by dissolving 1, 2, 3, 4, and 5 mg of the organic additives and 100 mg ammonium perchlorate in 2 ml of methanol as solvent. After that, the thermal decomposition behavior of prepared solid heterogeneous mixtures was monitored by thermogravimetry analysis, differential scanning calorimetry, and mass spectrometry analysis. The effect of the 4, 4’‐Bipyridine on thermal decomposition of AP enhanced the released heat from 479 to 1842 J g−1 and produced a decrease of decomposition temperature from 433 °C to 308 °C while the thermal decomposition of AP in the presence of biphenyl did not change as dramatically as it did with 4, 4’‐Bipyridine. With biphenyl, the decomposition temperature was found to be similar to that of pure AP and the evolved heat was about 718 J g−1. The gaseous products of decomposition of 4, 4’‐Bipyridine /ammonium perchlorate were monitored by mass spectrometric analysis. The main evolved decomposition gases of pure AP are N2O, O2, Cl2, ClO, ClO2, ClO3, HClO4, and HCl, while the major gaseous products of the 5:100 (w/w) mixture of 4, 4’‐Bipyridine with AP were detected as N2, NO, N2O, O2, Cl2, ClO, ClO2, ClO3, HClO4, HCl and 4, 4’‐Bipyridine. The change in the composition of volatile products indicates a change in the mechanism of AP decomposition from proton transfer to electron transfer in the presence of 4, 4’‐Bipyridine.