f. piri

The hexogen, RDX and cyclotetramethylene-tetranitramine (HMX) are of the strongest explosives known to be classified as secondary explosives. These compounds, and some other similar compounds, have N-N and N-O covalent bonds, which appear to be an important factor in their explosive and energetic properties. In this paper, the optimal structures and energies of the RDX and HMX and also the energy and structure of some other similar compounds are studied and compared. The selected compounds have an equal number of atoms and in the structure of all of them, the skeletons of 1,3,5-triazine and 1,3,5,7-tetraazine are preserved and the effect of other functional groups such as NH2 and N3 has been investigated. The results of calculations based on density functional theory showed that the amount of energy and structure stability of these compounds depends on the kind of functional groups and the way they are connected to the main ring. Dense phase heat of formation, crystalline density, detonation velocity and detonation pressure for the selected compounds were calculated.

Contamination of the environment by heavy metals, pollute water and agricultural products. The aggregation of these metals will cause various diseases for human. Therefore, it is important to study how to make them safe. The purpose of this study is to evaluate the efficiency of starch-iron oxide nanocomposite in removing two heavy metals, nickel and cadmium, from wastewater.

In this study, an attempt was made to use starch as natural polymer to prepare starch-iron oxide nanocomposites. Its structural properties and functional groups were investigated using scanning electron microscopy (FE-SEM), elemental decomposition (EDX) and Fourier transform infrared (FT-IR) spectroscopy. Then, the efficiency of starch-iron oxide nanocomposite as an adsorbent for the removal of heavy metals including nickel and cadmium from continuous synthetic solutions was investigated. For this purpose, aqueous solution with a concentration of 1000 mg/l of nickel and cadmium metals was prepared. The effect of adsorbent amount, pH and contact time on the removal process was studied. Langmuir, Freundlich and Temkin isotherm models were used for study of procedure isotherm.

The synthesized nanocomposite has good efficiency in removing nickel and cadmium. Maximum uptake of heavy metal ions was occurred at pH=4, using 0.05g of starch-iron oxide nano-composite from 20 ml aqueous solutions content 10 ppm of two studied ions. The adsorption efficiencies were found to be pH dependent which because of ionic interaction, by increasing pH value the removal increased. The cadmium adsorption process follows the Freundlich equation, while the nickel metal does not follow any of the equations. Investigations of kinetics of the process were performed and showed pseudo second-order model has the best correlation for adsorption procedure.

In general, this investigation showed that, the fabricated adsorbent has high efficiency for removal of nickel and cadmium ions. But application of this method in the industry should be economically evaluated.

The present paper seeks to examine factors affecting the sense of security of religious tourists on the border of Mehran as a model of border towns. The research method is descriptive-analytic. Data was collected through library studies and a questionnaire. Data were analyzed using SPSS software and hypotheses. Findings show that there is no meaningful relationship between personal characteristics of respondents between their age and their sense of security. There is a significant relationship between the sense of security and gender, the sense of security and education of the respondents, and the sense of security and the status of the marital status of the respondents. In terms of touristschr('39') safety, the security of a person with T=37.4 is most secure. Road safety with a T-value of 97.2 is in the lowest category security. According  the Sperman test, in the study of the relationship between total safety indices and sub-indicators of tourism development, the highest correlation coefficient between total security and re-visit with a correlation value of 5.30 is obtained. In examining boundary measures for border city security, the predicted variables predict 0.79% of the safety sensitivity variance, and all variables significantly predict safety. The efforts of security officials to secure security on both sides of the border with (Beta=0.526; has the highest impact on the variable of security.

The Convention on the Recognition and Enforcement of Foreign Arbitral Awards 1958 (known as the ‘New York Convention’) deals with recognition of arbitration contracts and the recognition and enforcement of arbitral awards. The decision of a court on the recognition of arbitration contracts and the recognition and enforcement of arbitral awards, is subject to arbitration contracts compliant with the formal provisions set forth in the Convention. Although the formal provisions of arbitration contracts are mentioned in article II(2) of the Convention, nevertheless the States Parties to the Convention have not interpreted this article in the same way. Nowadays specific approaches in the interpretation of this article are emerging which attempt to coordinate the application of the Convention with current commercial practice.