Designing a developed model for assessing the disaster induced vulnerability value in educational centers

To date, the models developed for assessing the vulnerability of societies have only taken account of the economic problems in the societies. Offering a model based on analytical hierarchy process and failure mode and effect analysis logic, the current study aims to determine the factors influencing the vulnerability of a higher education center and finally defines a vulnerability index. This model divides the factors influencing vulnerability into three categories: (1) the structure and layout of the buildings, (2) the occupants’ characteristics, (3) the controlling and warning systems. The academy community center of Science and Research Branch was assessed in terms of vulnerability. The findings indicated that the vulnerability value relating to various sections and university buildings was higher than the acceptable level which entailed the due attention of educational managers. The findings showed that if some parts of the educational and administrative buildings were used for laboratory as well as for the storage of hazardous and flammable materials, then the vulnerability value will be increased to 200. This highlights the impact that the type of buildings application has on the level of vulnerability. The study has been performed in the Science and Research Branch as an educational center in Tehran during 2009–2010.     

Preparation and Properties of Carboxymethyl Cellulose (CMC)/Sodium alginate (SA) Blends Induced by Gamma Irradiation

Carboxymethyl Cellulose (CMC)/Sodium alginate (SA) blends have been prepared by casting solution method. The effect of different irradiation doses (2.5, 5, 10, 15, and 20 kGy) of gamma rays on the physical properties of the CMC/SA blend containing different ratios of SA (20, 30, and 40 %) such as gel fraction (%) and swelling (%) of CMC/SA blends were investigated. It was found that the gel fraction increases with increasing irradiation dose up to 20 kGy while the swelling of CMC/SA blend films tends to increase with increasing SA content and reduced with increasing irradiation doses. Mechanical and thermal properties of the blend films were improved when CMC content increased and with increasing irradiation dose up to 20 kGy. Morphology of the blend was examined by SEM, which indicates compatibility between CMC and SA. The blend rich in SA content possessed good antimicrobial activity against Gram +ve Bacteria (Bacillus subtilis).     

Effect of dimethoate on the immune system of female mice

Abstract

The functional status of the immune system of female mice exposed to a single oral dose of dimethoate (16 mg / kg) was evaluated by assessing cell mediated and humoral immune responses, in addition to the effect of dimethoate on spleen and body weights after different time intervals. The data showed that dimethoate caused a time ‐ depended decrease in spleen weights in the absence of a change in body weights. The immunologic effect of dimethoate to female mice produced a dose‐dependent decrease in the number of the rosette forming cells (total and active erythrocyte rosette). The ability of splenocytes to proliferation in response to mitogens; phytohemagglutinin (PHA) for T cell and lipopolysaccharide (LPS) for B cell were significantly decreased at the different times. As compared to control, a significant decrease in serum total immunoglobulins (Ig) and IgM was found, while IgG was non‐significant deceased. Results of this study also revealed that dimethoate caused a significant decrease in the number of plaque forming cell (PFC / 10⁶ splenocytes) in a time dependent manner.     

Applying physicochemical approaches to control phosphogypsum heavy metal releases in aquatic environment

One of the most important sources of solid waste in the Mediterranean Basin ecosystem originated from the phosphate fertilizer industries, which discharge phosphogypsum (PG) directly into aquatic environments or are stacked on stockpiles. The present study investigates metal release from PG under the influence of variable pH, increasing PG mass content, and complexing organic matter ligands. Major ions from PG leachates, grain size and charge, main functional groups along with metal leachability (Pb, Cd, Cr, Cu, and Zn) were determined using ion chromatography, laser diffraction, zetameter, Fourier transform infrared spectroscopy, and atomic absorption spectroscopy, respectively. The complete dissolution of PG recorded is at 2 g/L. Saturation and supersaturation with respect to PG may occur at concentrations of 3 and 4 g/L, respectively, revealing a clustering phenomenon leading to heavy metal encapsulation within the aggregates. Organic ligands such as citrate may trigger the cationic exchange within the PG suspension leading to ion release. As these factors are considered as specific process involving the release of contaminants from PG during storage under natural conditions, this study could set the foundations for PG remediation in aquatic environment. Organic ligands under controlled pH conditions could be utilized in treating fertilizer industrial wastes by taking into consideration the particularity of the receiving area, thus decreasing metal hazardous impact on natural media.     

Chemical and biological release of 14C‐bound residues from soil treated with 14C‐p,p'‐DDT

Abstract

¹⁴C‐p,p'‐DDT‐bound residues in soil can be released by treatment with concentrated sulphuric acid at ambient temperatures. Within 6 days, about 70% of the bound residues was released. Bound residues released after 9 months incubation with ¹⁴C‐DDT showed the presence of DDT and DDE only while bound residues released after 18 months, contained in addition 13% DDD.

Release of bound ¹⁴C‐residues also occurs readily following inoculation of the soil‐bound residues with fresh soil or with individual microorganisms. Almost complete release of bound residues was observed after incubation for 45 days. The rate of release was rapid during the first two weeks and decreased thereafter. TLC and HPLC analysis showed that the released residues contained DDE (about 80%) and a smaller amount of DDD. The disappearance of DDT from the released residues may be attributed to its microbiological degradation to DDE and DDD, shortly after its release.     

Sequential UV-biological degradation of chlorophenols

The sequential UV-biological degradation of a mixture of 4-chlorophenol (CP), 2,4-dichlorophenol (DCP), 2,4,6-trichlorophenol (TCP), and pentachlorophenol (PCP) was first tested with each pollutant supplied at an initial concentration of 50 mg l(-1). Under these conditions, the chlorophenols were photodegraded in the following order of removal rate: PCP>TCP>DCP>CP with only CP and DCP remaining after 40 h of irradiation. The remaining CP (41 mg l(-1)) and DCP (13 mg l(-1)) were then completely removed by biological treatment with an activated sludge mixed culture. Biodegradation did not occur in similar tests conducted with a non-irradiated mixture due to the high microbial toxicity of the solution. UV treatment lead to a significant reduction of the phytotoxicity to Lipedium sativum but no further reduction of phytotoxicity was observed after biological treatment. Evidence was found that the pollutants were partially photodegraded into toxic and non-biodegradable products. When the pollutants were tested individually (initial concentration of 50 mg l(-1)), PCP, TCP, DCP, 4-CP were photodegraded according to first order kinetic model (r2>99) with half-lives of 2.2, 3.3, 5.7, and 54 h, respectively. The photoproducts were subsequently biodegraded. This study illustrates the potential of UV as pre-treatment for biological treatment in order to remove toxicity and enhance the biodegradability of organic contaminants. However, it also shows that UV treatment must be carefully optimized to avoid the formation of toxic and/or recalcitrant photoproducts and results from studies conducted on single contaminants cannot be extrapolated to mixtures.     

Androgens,oestrogens, and progesterone concentrations in wastewater purification processes measured with capillary electrophoresis

A novel analytical-scale concept to improve reliability of detection and analysis of natural and processed wastewater samples from a purification plant was developed. A sequential sample clean-up system of polymer-based octadecyl and silane-based quaternary amine sorbents were used for concentrating human based steroid hormones and their metabolites and detecting them by UV absorption with capillary electrophoresis (CE). The water samples were collected from influent and effluent processes of the water purification plant in Helsinki, Finland.The CE methods were partial-filling micellar electrokinetic chromatography and capillary zone electrophoresis. The analysis times and method concentration levels were optimized with eight steroids at the range of 0.5–10 mg/L. Since in CE the detectable quantities were higher than the existing amounts in the process waters, the real samples needed matrix removal combined with steroid enrichment. After 20,000-fold concentration testosterone-glucoside, androstenedione, progesterone, and estradiol-glucoside could be determined in the process water samples. The amounts of individual steroids in influent and effluent waters were 0–429 and 0–207 ng/L, respectively. Correspondently, their total amounts were 735 and 212 ng/L with excellent in day and inter-day repeatability. The RSD values were less than 1, 9.7, and 19% in repeated analyses, calculated from 60 analyses during 24 h, and from 130 analyses during 15 months, respectively. The steroid removal in purification process was 65% on average. The solid particles separated in three steps during the water clean-up concept contained 9.8–45 ng/g steroids in combined dry precipitates.     

Synthesis,Characterization and Application of Biodegradable Crosslinked Carboxymethyl Chitosan/Poly(Ethylene Glycol) Clay Nanocomposites

Crosslinked carboxymethyl chitosan (CMCh)/poly(ethylene glycol) (PEG) nanocomposites were synthesized using terephthaloyl diisothiocyanate as a crosslinking agent, in presence of montmorillonite (MMT), in different weight ratios of the two matrices. Characterization of nanocomposites was performed using different analyses. Swelling behavior was studied in different buffered solutions. It was found that formation of crosslinked CMCh/PEG nanocomposites increased the swell ability. Metal ions adsorption had also been investigated. The results indicated that crosslinked CMCh adsorbs various metal ions much more than non-crosslinked CMCh. Antimicrobial activity was examined against Gram-positive bacteria (S. aureus (RCMB 010027) and S. Pyogens (RCMB 010015), Gram-negative bacteria (E. coli (RCMB 010056), and also against fungi (A. fumigates (RCMBA 02564, G. candidum (RCMB 05096) and C. albicans (RCMB 05035). Data indicated that most of these nanocomposites exhibited good antimicrobial potency. Degradation studies were carried out in simulated body fluid for different time periods in order to find out the degradation index. Results showed that weight loss (%) of most of the nanocomposites increased as a function of incubation time.     

Endosulfan sulfate sorption on natural organic substances

This work proposes a viable remediation method based on the use of natural organic substances (NOSs) that characterize the Mediterranean region to improve the ecological system. A series of experiments, including variable conditions, such as temperature, pH, contact time, and pesticide concentration, were performed to demonstrate the efficiency of endosulfan sulfate removal from water by NOSs. Experimental results showed that the pH and temperature of pesticide solutions negatively affect the adsorption process. The maximum adsorption capacity for a specific initial concentration of endosulfan sulfate (0.5 microg/L) was achieved with Origanum compactum (75%), followed by Cistus ladaniferus and Raphanus raphanistrum (72 and 68%, respectively). The adsorption tests gave very satisfying results and point to the possible application of these supports as a remediation technique to prevent pesticide contamination of aquatic ecosystems.