Accumulation of heavy metals in agricultural soil irrigated by sewage sludge and industrial effluent (case study: Agh ghallah industrial estate)

Background and purpose: Industrial effluent and sewage sludge are used as fertilizer since they contain high levels of nutrient. The main pollutant in industrial effluent is heavy metals. In this study an assessment was made on the impact of industrial wastewater effluent and sewage sludge on accumulation of heavy metals in agricultural soil at Agh ghallah industrial Estate. Materials and methods: In a descriptive-analytic study, 72 samples (sewage sludge, effluent and soil) were collected from the Industrial state. All sampling and tests were performed according to standard methods and concentration of heavy metals was determined using polarography method. To analyze the data, SPSS was used and 95 confidence intervals (P 0.05). Conclusion: The concentrations of heavy metal were found lower than the maximum allowable level. Therefore, in this area, wastewater and sewage sludge could be used to irrigate agricultural lands and greenspaces in shortage of water, however, environmental regulations should be taken into account. © 2015 Mazandaran University of Medical Sciences. All rights reserved

The survey of removal of suspended solids from river at flooding period by plain sedimentation process

The most important of surface sources of water in the large city are rivers. The turbidity and flow rate of rivers is a constantly changing phenomenon in the seasons from year. During rainy period, the run off carries with it silt, clay and sand which make a severe increasing in turbidity to over 1000NTU. The increasing of turbidity causes which the water plant treatment receives the more solides.However; in order to protection of plant units must apply pretreatment processes. In this research, the effectiveness of settling process in order to removal of TSS from raw water was studied. The beginning of the work, lab-scale pilot designed which consisted of a raw water preparation container; the settling column was made of Plexiglas with 2m height, 20cm diameter and the six of sampling ports. The settling column filled with the raw water associated with sediments of river. At defined time steps (30-60-90-120-150-180 min) samples were taken out from the bottom of the column (180cm under water surface). The temperature of water was in the range of 15 to 18oC during experiments. The results showed that between the increasing of TSS removal and settling time, a direct and significant relative (p<0/01) was obtained by Pearson, s correlation coefficient. Also with increasing the depth, the removal efficiency of TSS and turbidity decreased. In the settling time of 30min, 2640mg/L of TSS concentration, the depths of 30 and 180cm, systematically, the TSS removal 92.42% and 80.47% was obtained. when the initial TSS concentration increase to 27640mg/L (the most concentration of TSS), with increasing SOR from 25m/d to 60m/d, the total removal efficiency decreased from 99.2% to 92.2%, and with the TSS of concentration equals to 2640mg/L, the rate of total removal efficiency decreased from 97.2% to 95.7%. The results showed that the rising of SOR and TSS concentration, decreased the total removal efficiency. Also, these are an opposite and significant relative (p<0/05) between the removal of TSS and initial concentration of TSS

Effectiveness of chitosan as natural coagulant aid in removal of turbidity and bacteria from turbid waters

There has been considerable interest in the development of natural coagulants such as chitosan. By using natural coagulants, considerable savings in chemicals and sludge handling cost may be achieved. Chitosan, a natural linear biopolyaminosaccharide, is obtained by alkaline deacetylation of chitin. Present study is aimed to examine the effects of aluminium sulfate (alum) as coagulant in conjunction with chitosan as coagulant aid on removal of turbidity and bacteria from turbid waters. These tests were carried out using artificial water and kaoline as model suspensions to represent the wide range of natural turbid waters. A conventional jar test apparatus was employed for the tests. After determining of optimum mixing intensity and duration, alum suspensions were added to the samples and after one minute, the desired doses of natural chitosan were added. In optimum condition, residual Al+3 in treated water was less than 0.2 mg/l and meets the EPA guidelines. Turbidity removal efficiency was 74.3- 98.2% by chitosan at a pH 7.0-7.5 for all turbidities. In addition, chitosan significantly reduced the required dosage of primary coagulant 50-87.5%. Bacteria reduction of 2-4 log units (99 - 99.99%) was obtained within the first 1 to 2 h of treatment. Overall results indicate that E.coli was removed better than S. faecalis. The main effects of coagulation by chitosan on bacteria are enmeshment and stack on the microbial cell surface. We demonstrated that optimal design method is an efficient approach for optimization of coagulation-flocculation process and appropriate for raw water treatment

Designing a Robust Decentralized Energy Transactions Framework for Active Prosumers in Peer-to-Peer Local Electricity Markets

In this paper, a fully decentralized local energy market based on peer-to-peer(P2P) trading is proposed for small-scale prosumers. In the proposed market, the prosumers are classified as buyers and sellers and can bilaterally engage in energy trading (P2P) with each other. The buyer prosumers are equipped with electrical storage and can participate in a demand response (DR) program while protecting their privacy. In addition to bilateral negotiating with the local sellers, these players can compensate for their energy deficiency from the upstream market as the retail market at hours without local generation. In this paper, the retail market price is assumed uncertain. Robust optimization is applied to model this uncertainty in the buyer prosumers model. The proposed decentralized robust optimization guarantees the solution’s existence for each realization of uncertainty components. Furthermore, it performs optimization to realize the hard worse case from uncertainty components. A fully decentralized approach known as the fast alternating direction method of multipliers (FADMM) is employed to solve the proposed decentralized robust problem. The proposed approach does not require third-party involvement as a supervisory node nor disclose the players’ private information. Numerical studies were carried out on a small distribution system with several prosumers. The numerical results suggested the operationality and applicability of the proposed decentralized robust framework and the decentralized solving method

A Light, Transmission and Scanning Electron Microscope Study of Snuff-Treated Hamster Cheek Pouch Epithelium

The effects of smokeless tobacco (snuff) on hamster cheek mucosa were studied by light microscopy, transmission (TEM) and scanning electron microscopy (SEM). Two grams of commercially available smokeless tobacco were placed into the blind end of the right cheek pouch of each experimental animal, once a day and five days a week for 24 months. The control animals did not receive smokeless tobacco. After 24 months treatment with smokeless tobacco, hamster cheek mucosal epithelium lost its translucency and had become whitish in color. By light microscopy hyperorthokeratosis, prominent granular cell layers with increased keratohyalin granules and hyperplasia were seen. At the ultrastructural level, wider intercellular spaces filled with microvilli, numerous shorter desmosomes, many thin tonofilament bundles, increased number of mitochondria, membrane coating granules and keratohyalin granules were seen in snuff-treated epithelium. The changes in the surface of the epithelium as seen by SEM were the development of an irregular arrangement of the microridges and the disappearance of the normal honeycomb pattern. The microridges were irregular, widened and surrounded the irregular elongated pits. Some smooth areas without microridges and pits were also seen. The long-term histological, TEM and SEM changes induced by smokeless tobacco treatment of the epithelium are well correlated with each other and were similar to those reported in human leukoplakia without dyskeratosis. They imply changes of pathological response resulting from topically applied snuff

The Effect of Increasing Cognitive Load of Rhythmic Games on Theory of Mind in Children with Developmental Coordination Disorder

Background : The purpose of the present study was to determine the effect of increasing cognitive load of rhythmic games on theory of mind in children with developmental coordination disorder. Method: This is a quasi-experimental research. Participants in this study were 25 children (9 boys and 16 girls) aged 8 to 10 years old who were screened based on Parental Developmental Coordination Disorder Questionnaire (DCD- Q07) and confirmed for their impairment using the Movement Assessment Battery for Children (MABC) Test. All participants underwent Raven's test in the same condition and students with normal intelligence entered the study. Participants were matched in two groups of experimental (n = 13) and control (n = 12). The experimental group performed rhythmic games with cognitive load for 8 weeks and 2 sessions of 45 minutes per week, but the control group received only rhythmic games intervention. Participants were assessed before and after the intervention by Steerneman theory of mind test. Statistical analysis was performed using univariate and multivariate covariance tests. Results: The results indicated that rhythmic games with cognitive load developed the theory of mind in children with developmental coordination disorder (P=0.01). Conclusion: Since cognitive load rhythmic games have a positive effect on the theory of mind in children with developmental coordination disorder, it is recommended that these exercises be included in the daily activities of these children

Possibility of using fresh water rotifer Brachionus calyciflorus for feeding Persian sturgeon Acipenser persicus

Acipenser persicus, one of the native Species living in the southern part of the Caspian Sea, has high Percentage of larval mortality. Therefor to decrease the rate of mortality of larvae survival and to increase to regenerate properly during the active feeding process of fish larvae, while under artificial reproduction they were fed withe fresh water rotifer. Four types of feeding treatments were applied as follow: Treatment 1: Similar to normal process, first withe Artemia cyst then withe Daphnia Treatment 2: Mixture of Artemia, Rotifer and Daphnia; Treatment 3 freshwater Rotifera ;Treatment 4: fresh water Rotifer enriched with Vitamin C (Ascorbic acid- 6- Palmytat).Three replicates were used for each treatment. In the process of each observation 45 larvae in containers withe 100 liter capacity filled with 30 liters of water, after 8 days of external feeding process, were inspected closely, during which , they were under biometric measurement once every two days. Larvae were fed Four times a day at a rate of 25% of their body weight. The average temperature estimation was 22.5±0.5 centigrade, pH .of water being 85±0.1 while Oxygen proved to be 9.58±0.2 mg/l. At the end of the observation, the profile fatty acids of the remains were studied. The growth factors, the mouth size of the larvae and the expansion of the mouth size compared to the total length of the larvae during the whole observation were inspected. Credibility of data designated was examined by Shapiro Wilks test. Specific growth rate (SGR), weight growth (WG) and feed conversion ratio (FCR) were contemplated by one-way analysis test, and significant difference Tukey's test. The most notable diversity was evident between treatment 2, whose indicative factors were in the following order: 4.65± 0.06, 45.18±0.66, 4/48 ± 0/07 and treatment 4 whose indicative factors showed the following results: 10.47±0.04, 124.42±0.62, 1.51±0/008.For the determination of fatness rate and weight gains, Kruskal Valis and Man vit ni test were used .In this part of study , the highest diversity fatness appeared to be between treatment 4 ,reflecting 0.79±0.07 and treatment 2 showing the result 0.62±0.05.The highest gain was related to treatment 4, whit the rate of 99.33±0/68 mgr and the lowest gain occurred in treatment 2 white the rate 62.36 ± 0.65 mgr. This study also revealed that, the survival ratio connected with treatments 3 and 4, compared treatments 1 and 2, were significantly different. The profile of fatty acids also showed much higher percentage of PUFA and HUFA in treatments 3 and 4, than those in other treatments. Furthermore Brachionus calyciflorus proved to be a proper food supply for larvae. Therefore by building suitable pools next to the work side, other kinds of species fresh water rotifer could also be used as food improvements for feeding larvae