Open Access Case study

Potential Devastating Domino Effect: A Case Study of Msasa Industrial Area, Zimbabwe

N. Mudavanhu, P. Dzomba, L. D. Mudehwe

Chemical Science International Journal, Page 50-64
DOI: 10.9734/ACSJ/2013/2677

Aims: To assess the likelihood of occurrence of domino effect in a group of neighbouring companies in Msasa Industrial area.

Study Design: A case study approach was used.

Place and Duration of Study: Msasa industrial area, Harare Zimbabwe between June 2011 and June 2012.

Methodology: Information was sought through interviews, questionnaires and observations from 15 companies in Msasa. The What If Analysis (WIA) was also used to postulate the potential upsets that may result in accidents. A semi qualitative approximate domino effect analysis procedure was used to simulate the likely sequence of an event after its initiation.

Discussion: In the cluster, domino effect was most likely to be initiated and propagated by fires (pool, flash, fireballs or jet), explosions (confined vapour cloud explosions (CVCE), boiling liquid expanding vapour explosions (BLEVE), vented explosions, vapour cloud explosions, and dust explosions) and toxic release with effects ranging from being catastrophic, critical, marginal or negligible. It was found that there has been no domino risk analysis and hence was a strong possibility of destruction of the entire industrial area and neighbouring residential areas in the case of the forecast domino accidents. Toxic and dust releases were most likely to contaminate neighbouring residence leading to exposed toxic substance for long periods after the release.

Conclusion: Msasa industrial area may pose a serious domino effect risk, hence the need to make it mandatory for domino effect analysis studies in industrial areas and sharing safety information with neighbouring companies and communities.


Open Access Original Research Article

Yttria Nanoparticles Prepared from Salicylic Acid-Y(III) Nanocomposite as a New Precursor

Maryam Ranjbar, Soraya Mannan, Mohamad Yousefi, Anvar Shalmashi

Chemical Science International Journal, Page 1-10
DOI: 10.9734/ACSJ/2013/1618

A novel method for the fabrication of high purity yttria, Y2O3, nano-particles is presented by thermal decomposition of salicylic acid-Y(III) nano composite as precursor. The nano composite was formed by a sonochemical method from the reaction between Y(III) nitrate hexahydrate, potassium tiocyanide, KSCN, and 2-hydroxyl benzoic acid, (salicylic acid = sal) in ethyleneglycol, eg, under ultrasonic irradiation with the rated output power of 600 W and frequency 20 KHz. Characterization of the mentioned compound was performed by FTIR spectroscopy, elemental analysis, scanning electron microscopy (SEM) and thermal analysis, TG/DTA. Yttria, nanoparticles were prepared by thermal decomposition of the nano composite at two different conditions in ambient atmosphere. The product was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and fourier transform infrared (FT-IR) spectroscopy. The purity of Y2O3 nano-powder tested by ICP-AES analysis is 99.99%.


Open Access Original Research Article

Thermochemistry of Heteroatomic Compounds: Interdependence between of Some Thermochemical Parameters of the Different Classes Organic Nitro Compounds and a Number of Valence Electrons in their Molecules

Vitaly Ovchinnikov

Chemical Science International Journal, Page 11-23
DOI: 10.9734/ACSJ/2013/2079

The linear equation ∆cHo = i + f (N - g), in which i and f are the factors of correlation, describing interdependence between then heat of combustion organic compounds and their number (N) valence electrons except for a number of lone electron pairs (g) heteroatoms in them, it has been applied besides to the most thermochemical parameter for mono-, di- and trinitroalkanes, arenes and alkylated nitramines. It has appeared, that the given equation also is good applicable to calculation of the heats of formation, vaporization and atomization of nitro compounds in condensed and gas phases. Twenty six similar equations for calculation of thermochemical characteristics of substances with NO2 groups have been deduced on the basis of the analysis known in literary thermochemical parameters for 53 organic nitro compounds. The estimation of value coefficients f in these equations for calculation of the heats of combustion, formation in condensed and gaseous phases, vaporization, sublimation and atomization mononitro alkanes, various nitramines, dinitro alkanes and arenes, trinitroalkanes and arenes is made.

Open Access Original Research Article

Modified Composite Activated Carbon Derived from Post-Consumer Plastics and Lignocellulosic Materials

Abdoul Ntieche Rahman, Loura Benguellah Benoît, Abdelaziz Bacaoui, Ketcha Joseph Mbadcam

Chemical Science International Journal, Page 24-33
DOI: 10.9734/ACSJ/2013/2210

The composite activated carbons were produced using both lignocellulosic materials and urban waste plastics and their characteristics were investigated. The mixture of raw material was first carbonized at 600ºC in N2 atmosphere. The char obtained was then mixed with KOH (in the ratio 2:1 for KOH/char) before the activation process with steam at 850ºC. The results show that composite carbons are micro, mesoporous and have higher carbon yield compared to the carbons from both pure raw materials, which are mainly mesoporous. These results were confirmed by their high adsorption of methylene blue. BET surface area for all the samples were over the acceptable range (991.5 - 1412.9). Moreover, the average size of the pores of carbon between in the range of 1.8 – 2.3 nm. Carbon surfaces were analyzed in detail using FTIR and SEM, exhibiting hydroxyl and carboxylic functional groups on the surfaces and cavities of mesopore size.


Open Access Original Research Article

Synthesis and Antibacterial Activity of N,N-Diethylamide Bearing Benzenesulfonamide Derivatives

Olayinka O. Ajani, Oluwole B. Familoni, Johnbull O. Echeme, Feipeng Wu, Zheng Sujiang

Chemical Science International Journal, Page 34-49
DOI: 10.9734/ACSJ/2013/2397

Sulfonamides are known to represent a class of medicinally important compounds which are extensively used as antibacterial agents. Hence, a series of new N,N-diethyl amide bearing sulfonamides (2a-k) were synthesized via amidation of easily prepared benzenesulfonamide precursors (1a-k). The chemical structures of all synthesized compounds were substantiated using spectroscopic means such as IR, Mass spectra and 1H-NMR as well as analytical data. The antimicrobial activity of these compounds along with streptomycin, was investigated on Escherichia coli and Staphylococcus aureus. The results showed that this skeletal framework exhibited marked potency as antibacterial agents. The most active antibacterial agent against both targeted organisms was N,N-diethyl-1-(phenylsulfonyl) piperidine-2-carboxamide (2b).


Open Access Original Research Article

Cyclotriveratrylene Dendrimers with a Fullerene C60 in the Dendritic Branches

Karla E. Sanchez-Montes, Tatiana Klimova, Mark E. Martínez-Klimov, Marcos Martínez-García

Chemical Science International Journal, Page 65-79
DOI: 10.9734/ACSJ/2013/2467

Dendrons with dodecyl terminal groups joined to benzyloxy moieties were attached to a cyclotriveratrylene core. The dendrimers were used in Bingel cyclopropanation reaction with the fullerene C60. The structure of the synthesized dendrimers was confirmed by 1H- and 13C-NMR, MALDI-TOF mass spectrometry and elemental analysis.