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Isolation and morphological study of ecologically-important insect “Hermetia illucens” collected from Roorkee compost plant
2017
Purkayastha, Debasree | Sarkar, Sudipta | Roy, Partha | Kazmi, Absar
Certain species of Hermetia illucens, also known as the Black Soldier Fly(BSF), were found in a compost plant in Roorkee located in Northern India. Its larvae arevoracious eaters of organic waste, hence can play an ecologically-important role in solidwaste management. Morphological analysis of various stages of BSF life cycle by SEMshowed that its body along with its wings is densely covered with hair. The identifiedspecies of BSF were black in color and oviposited into the composted material. The larvaegrew up to 30 mm long in 12 days from an initial length of only 6mm, gaining almost 200%of its initial weight after voraciously feeding on organic waste. The mouth of the H. illucensshowed a well-developed mandibular-maxillary complex that had similar characteristics ofscavengers, making the insect a suitable candidate for organic waste consumption.
显示更多 [+] 显示较少 [-]Removal of Hg (I) and Hg (II) Ions from Aqueous Solutions, Using TiO2 Nanoparticles
2017
Afshar, Elahe | Mohammadi-Manesh, Hossein | Dashti Khavidaki, Hossein
For the first time, the present study removes ions of mercury, in the form of Hg (I) and Hg (II) ions, from aqueous solutions by adsorbing them onto titanium dioxide nanoparticles. The effects of various parameters, such as solution's initial pH, temperature, sorbent dosage, initial mercury concentration, and contact time have been examined on the adsorption process. The experimental results have been compared with Langmuir, Freundlich, and Temkin adsorption isotherms. The maximum adsorption, obtained for Hg (I) and Hg (II) ions, have been 97.5% and 98.6%, respectively. Also, it has been shown that the Langmuir isotherm has better fitting with the equilibrium data than the Freundlich and Temkin isotherms. Thermodynamic parameters of the adsorption, such as and have been calculated, the negative values of which show that the mercury ions adsorption is an exothermic process and that randomness is decreased, respectively. The study of adsorption kinetics shows that the adsorption of Hg (I) and (II) ions with TiO2 nanoparticles is pseudo-second order.
显示更多 [+] 显示较少 [-]Status of CO as an air pollutant and its prediction, using meteorological parameters in Esfahan, Iran
2017
Masoudi, Masoud | Gerami, Soraya
The present study analyzes air quality for Carbon monoxide (CO), in Esfahan with the measurements taken in three different locations to prepare average data in the city. The average concentrations have been measured every 24 hours, every month and every season with the results showing that the highest concentration of CO occurs generally in the morning and at the beginning of night, while the least concentration has been found in the afternoon and early morning. Monthly concentrations of CO show the highest values in August and the lowest values in February. The seasonal concentrations show the least amounts in spring, while the highest amounts belong to summer. Relations between the air pollutant and some meteorological parameters have been calculated statistically, using the daily average data. The data include Temperature (min, max), precipitation, Wind Direction (max), Wind Speed (max), and Evaporation, considered independent variables. The relations between the pollutant concentration and meteorological parameters have been expressed by multiple linear regression equations for both annual and seasonal conditions, using SPSS software. Analysis of variance shows that both regressions of ‘enter’ and ‘stepwise’ methods are highly significant, indicating a significant relation between the CO and different variables, especially for temperature and wind speed in annual condition. RMSE test shows that among different prediction models, stepwise model is the best option.
显示更多 [+] 显示较少 [-]Levels of natural radioactivity in environment in residential area of Moradabad District, Western Uttar Pradesh
2017
Rastogi, Nikhil | Singh, Indu
Indoor radon and thoron have been measured in the houses ofMoradabad District, Uttar Pradesh India, by means of solid state nuclear trackdetectors. Radon, an invisible radioactive gas, occurs naturally in indooratmospheres and along with thoron is the most important contribution of humanexposure to natural sources. Radon exists in soil gas building materials and indooratmosphere to name but a few. Risk of lung cancer depends on the concentrationof radon and thoron and their decay products in the environment aboverecommended levels. The present article measures the concentration of indoorradon and thoron in 60 dosimeters by means of a solid state nuclear track detectorin different house types of Moradabad district, Uttar Pradesh. The measurementshave been carried out in residential buildings at a height of 2 m from the sea level,using a twin chamber radon dosimeter. The value of radon concentration in thepresent study varies between 10.5 Bq/m3 and 29.5 Bq/m3 with an average of 19.8Bq/m3 while that of thoron is between 5.6 Bq/m3 and 24 Bq/m3 with an average of14.9 Bq/m3 respectively. Results, obtained with twin cup radon/thoron dosimeter,show that the concentration of indoor radon and thoron have been within therecommended level, with all the values staying under the safe limits, decreed bythe International Commission on Radiological Protection (ICRP) and UnitedNations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR).
显示更多 [+] 显示较少 [-]Evaluation of Cadmium Removal from the Water in Phytoremeiation Process Using Eichhornia crassipes
2017
Asrari, Elham | Avatefi Nezhad, Goltab
Conserving water resources and protecting them from pollution are of high account in the natural cycle of our life. This study has tried to determine the refining potential and capacity of water hyacinth (Eichhornia crassipes) in order to remove the cadmium from water, studying the influence of factors such as initial concentration of cadmium, contact time, absorbent mass, and pH. Results have shown that the best efficiency of cadmium, more than 99%, was obtained in the optimum conditions (i.e. retention time of 30 hours, adsorbent dose of three plants (12 stems), and pH=6.6). By increasing the initial concentration of cadmium from 0.28 to 8.28 mg/L, the elimination efficiency did not change; moreover, by increasing the absorbent mass, the elimination efficiency increased from 98.4 to 99.8 and the lowest retention time was obtained for the balance. All experiments have been repeated three times, showing in the end that water hyacinth is able to absorb cadmium up to 8.28 mg/L. This process follows Freundlich isotherm (R2=0.98). Results of this study indicate that this plant can grow well at high levels of cadmium and the growth of water hyacinth is better in the presence of cadmium than control conditions (city water). Finally, it can be concluded that it is necessary to provide a reliable, cheap, and fast method to eliminate pollution. Eichhornia crassipes, a promising plant with great functionality, can be used as a refiner in order to eliminate the heavy metals in wastewater (sewage) effluents, particularly industrial sewage.
显示更多 [+] 显示较少 [-]Utilization of temple floral waste for extraction of valuable products: A close loop approach towards environmental sustainability and waste management
2017
Singh, Pardeep | Borthakur, A. | Singh, R. | Awasthi, Sh. | Pal, D.B. | Srivastava, P. | Tiwary, D. | Mishra, P.K.
This study presents the natural dye recovery from various biodegradable temple and household wastes. The raw material for colour extraction consisted residual flowers and garlands from various temples as well as onion and vegetables peels from vegetable markets, university hostels, and households, which were washed, dried, crushed, and sieved. The extracted natural colours were produced by means of ultra-sonication, and were dried in the spray drier, being characterized by FT-IR and UV-Vis Spectrophotometers. They were used to dye various fabrics such as cotton, silk, and wool, not to mention different mordents. It was found out that the remaining residue, left after dye extraction, was rich in nutrients, hence, it could be further used as the resource material, itself. As a result, we explored these residual wastes for vermicomposting and biochar production, which can be further employed as an organic fertilizer for agriculture. Overall, the present waste management approach will lead to a closed-loop environmental management through waste reduction and reutilization. It will also provide value-added materials for economic gains from waste. Thus, it can be promoted as a potential mechanism to maintain the environmental sustainability at wider scales.
显示更多 [+] 显示较少 [-]Determination of nitrate utilization efficiency of selective strain of Bacillus sp. isolated from Eutrophic Lake, Theerthamkara, Kasaragod, Kerala
2017
Usharani, K. | Sruthilaya, K. | Divya, K.
Nitrate pollutants increase the growth of algal bloom, resulting in fresh water eutrophication. The high nitrogen level in wastewater has become a growing concern, which has risen the necessity to develop efficient nitrogen removal techniques. Biological denitrification, which is the reduction of oxidized nitrogen compounds like nitrate or nitrite to gaseous nitrogen compounds, is the most important and widely used method to treat nitrate wastes as it enables the transformation of nitrogen compounds into harmless nitrogen gas. As such, this study collected samples from Eutrophic Lake, picking isolates of bacterial strain with good growth rates in the nitrate medium. The selected bacterial strains were cultured on media 1and 2 and by means of UV-visible spectrophotometer, the nitrate removal efficiency and growth were detected at 410 nm and 600 nm OD respectively. After comparing three bacterial strains, it was found that RN1 had a higher efficiency in nitrate removal at 1000ppm nitrate concentration. At an optimum temperature of 37°C, pH of 7, and agitation of 121 rpm, after 432 hrs of the treatment, RN1 showed an optimum growth, equal to 0.1859 OD in 1000ppm nitrate solution with dextrose. Also the spectral analysis of RN1 strain showed 85% removal efficiency, thus making this strain the best one. Confirmed and identified as Bacillus species, it can be recommended for the bioremoval process of nitrate from wastewater.
显示更多 [+] 显示较少 [-]Growth-phase dependent biodesulfurization of Dibenzothiophene by Enterobacter sp. strain NISOC-03
2017
Papizadeh, Moslem | Roayaei Ardakani, Mohammad | Motamedi, Hossein
Petroleum-polluted soil samples from Ahvaz oilfield were enriched, using three methods to detect microorganisms with different dibenzothiophene degradation capabilities. Strain NISOC-03, a nitrate-reducing, oxidase negative, catalase, citrate, and urease positive, gram negative rod, showed interesting dibenzothiophene desulfurization behavior, designated as Entreobacter sp. strain NISOC-03 based on phenotype and genotype analyses. Gas chromatography, biomass measurement, and Gibb’s assay showed that in the presence of benzoate as the carbon source, strain NISOC-03 utilized 64% of 0.8 mM dibenzothiophene, producing 0.27 mM phenyl phenol during the exponential growth phase, though the produced phenyl phenol was degraded in the stationary growth phase. In the presence of glucose as the carbon source, however, strain NISOC-03 metabolized only 19.6% of 0.8 mM dibenzothiophene. Furthermore, replacing glucose with ethanol or glycerol led to the same reduction of the dibenzothiophene utilization. It is thus concluded that the chemistry of the potential carbon source(s) in the culture medium has a significant influence on the quality and the rate of dibenzothiophene metablization, and the enrichment designation has a very vital effect on the biodegradation efficiency of the isolated microorganisms.
显示更多 [+] 显示较少 [-]Evaluating the application of wastewater in different soil depths (Case study: Zabol)
2017
Shojaee, Saeed | Zehtabian, Gholamreza | Jafary, Mohammad | Khosravi, Hasan
Water scarcity, its necessity in food production, and environmental protection in the world have forced human beings to seek new water sources. Nowadays, application of unconventional water resources (wastewater) has been proposed in countries facing the crisis of water resources shortage; however, a few studies have dealt with this issue. The present study has evaluated the changes in the elements of the soil, irrigated with wastewater. For so doing, an experiment has been conducted on a randomized complete block design with three replications. Soil samples have been collected from the studied regions at two depths of 0-30 cm and 30-60 cm and the studied parameters have included sodium, total calcium, magnesium, some acidity, and electrical conductivity of the soil. Three regions of study (namely no irrigation, irrigation with treated wastewater, and irrigation with river waters) have been taken into consideration. Results have shown increased calcium, magnesium, and pH of the effluent from Zabol Wastewater Treatment Plant compared to the control; however, electrical conductivity and chloride have decreased in wastewater-irrigated soil. The electrical conductivity in the surface layer of wastewater samples, treated with an amount of 2.25 (ds/m), has had the most significant difference to the control and other treatments. It can be concluded that wastewater increases some soil properties, contributing to its restoration.
显示更多 [+] 显示较少 [-]Statistical modeling of the association between pervasive precipitation anomalies in Southern Alburz and global ocean-atmospheric patterns
2017
Molanezhad, Mahmoud
Precipitation patterns are influenced by many factors, such as global atmospheric circulations to name but one. Precipitation patterns in Iran have always had great fluctuations even in a smaller scale like the Alburz Mountain Range. The present research has tried to find the relationship between global atmospheric patterns and the pervasive precipitation ones in Alburz. For doing so, 17 climate indices have been chosen with the correlation between these indices and the precipitation data calculated in different lag times, using a backward correlation method (from the present time to 3 months earlier). Based on the obtained correlation results, a regression modeling has been conducted that employs a backward method. As for each lag time, one equation has been offered to estimate the amount of precipitation for every single region. Results have shown that the Bivariate ENSO Time Series (BEST) and the East Pacific Oscillation (EPO) provide the highest correlation with the pervasive precipitation time series. Also, it has been demonstrated that in multivariate correlation, the efficient index to model the relation among these indices as well as precipitation in southern Alburz alters in each lag time. Both MBE and RMSE, employed to evaluate the modeling, show relatively acceptable values, implying that the equations are acceptably capable of predicting the amount of precipitation in both northern and southern Alburz.
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