Wei Jiang, University of Massachusetts, Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, Amherst, MA, USA, Tel: 413-545-3862, Fax: 413-545-3958, Email: wjiang@psis.umass.edu
Hamid Mashayekhi, University of Massachusetts, Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, Amherst, MA, USA, Tel: 413-545-3862, Fax: 413- 545-3958, Email: hamid@psis.umass.edu
Dr. Baoshan Xing, University of Massachusetts, Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, Amherst, MA, USA, Tel: 413-545-5212, Fax: 413- 545-3958, Email: bx@pssci.umass.edu

Nanotechnology is considered as one of the world’s most promising new technologies in this century. When materials are made in nanoscale (smaller than 100 nm), their properties and applications change vastly from ordinary materials with a same composition. Due to the expected wide use and large quantity production, manufactured nanomaterials will be inevitably released into the environment. The small size and unique properties of nanomaterials make them active in unusual ways in the environment and reacting with living organisms. Therefore, there are serious concerns about their adverse impacts in the environment including their toxicity. In this study we examined the toxicity of three oxide nanoparticles, i.e. zinc, aluminum, and silicon oxides as well as C60 fullerene to three bacteria: Bacillus subtilis, Pseudomonas fluorescence, and Escherichia coli. Bulk oxide particles and activated charcoals were used as control. Bacteria were grown in TS broth for 24h. Then the bacteria were separated from the broth, washed with an electrolyte solution and incubated with prepared sterilized nanoparticle water suspension for three hours. A decrease in bacterial population compared to that of control treatment was used as a toxicity indicator. All nanoparticles showed signs of toxicity compared to control. Toxicity of nanoparticles was independent from the dissolved elemental concentration. Sensitivity of different bacteria to each nanoparticle was different. Zinc oxide nanoparticles were most toxic among the studied particles. AFM and TEM images confirmed the attachment of nanoparticles to the surface of bacteria. We concluded that the studied nanoparticles were significantly more toxic than their bulk counterparts. Further work is needed to study the effect of natural environmental parameters on nanoparticle toxicity. This study emphasizes the important environmental implications of manufactured nanoparticles.

Testing a New Bioreactor Model for Biogas Production by Utilizing Municipal Solid Waste

Dr. Jeeban Shrestha, Amrit Science College, Tribhuban University, Faculty of Science and Technology, P.O.Box:8974, CPC-528, Kathmandu, Nepal , Tel: 977-1-4492872, Mobile : 977-9841-342656, Email: jeebanmanab@yahoo.com

Production of biogas as a renewable energy from organic fraction of municipal solid waste (MSW) is investigated in the present study. A new model of bio-reactor of 1800-liter capacity was designed and successfully tested. The bio-reactor was loaded with an input of 340 kg of MSW, which was diluted with 340 liter of water. The initial pH of the substrate was recorded to be 4.9. Substantial gas production was noted after 88 days of anaerobic fermentation. The bio-reactor produced 22 litres of biogas from 1 kg of MSW under ambient temperature. The digested slurry coming out from bio-reactor contained 1.16% Nitrogen, 0.32% Phosphorus, 2.5% Potassium and the pH of the slurry was 7.3. Based upon this study, some suggestions to increase the efficiency of the bio-digester have been made. The present model opens ways and possibilities for further research for production of biogas and bio-fertilizer from MSW at mass scale in order to mitigate environmental pollution problems which are acute in urban areas of this country and all over the world. It has opened ways to cut massive methane emission in environment, healthy waste management system and source of organic fertilizer.

Teaching Green – Upper Cape Cod Regional Technical School a Renewable Energy Pioneer

Frank Ricciardi, P.E., LSP, Weston & Sampson, Inc., 5 Centennial Dr., Peabody, MA 01960, Tel: 978-532-1900, Email: ricciarf@wseinc.com
Kevin Farr, Upper Cape Regional Technical High School , 220 Sandwich Road, Bourne, MA 02532, Tel: 508 759-7711, Email: kfarr@uppercapetech.org

Upper Cape Cod Regional Technical School (UCT) is a regional school district in the Commonwealth of Massachusetts.  For more than thirty years, high school students and adults seeking continuing education from the towns of Bourne, Falmouth , Marion , Sandwich, and Wareham have turned to UCT for quality educational opportunities. Recently, the school has developed an impressive curriculum focusing on renewable energy. Weston & Sampson has been working with UCT to enhance their already stellar renewable energy curriculum with real-world renewable energy and engineering projects related to the design of a Leadership in Energy and Environmental Design (LEED) accredited marine sciences building. This building will utilize green energy generated from an onsite commercial-scale wind turbine to be designed by Weston & Sampson and UCT students. Student involvement will be a main focus during the design and construction of these projects to ensure that the next generation of UCT graduates embraces renewable energy and understands the basic science behind these technologies. The Massachusetts Technology Collaborative (MTC) recently selected UCT to receive a Large Onsite Renewables Initiative (LORI) grant for the completion of a wind power feasibility study at the Site. In addition, UCT has recently installed photovoltaic cells at the school to power domestic hot water heaters and biodiesel fuel is being generated in the school’s laboratories to fuel a student-converted school vehicle.

This paper will discuss the renewable energy curriculum developed by the school and will present the recent design of the LEED-accredited marines sciences building and the results of the wind power feasibility study. The paper will also present the many student involvement opportunities that were available during the completion of these projects. Students used these opportunities to learn about the science and engineering evaluations associated with renewable energy projects and LEED design/construction techniques.

Multiresistant Microorganisms of Sewage from Leaky Sewers Pass the Urban Underground and Enter the Groundwater

M. Paul, PD, Dr. C. Gallert and Prof. Dr. J. Winter, University of Karlsruhe , Department of Biology for Engineers and Biotechnology of Wastewater treatment, Am Fasanengarten, D-76228 Karlsruhe, Germany, Tel: 0049-721-608-2297 or –2696,  Email: Claudia.Gallert@iba.uka.de; Josef.Winter@iba.uka.de

Background: In Europe sewers are more than 50 years old and leaky. Raw sewage is trickling through the vadose zone and is entering the groundwater after “soil filtration”. Since sand filters are used to remove bacteria from purified wastewater as the final treatment step, we investigated whether trickling of raw sewage through 1 – 2.5 m of sandy soil would be enough to prevent groundwater contamination with feacal bacteria or pharmaceuticals.

Research tools: The fate of trickling sewage was investigated in water-saturated and nonsaturated, aerobic or anaerobic sand columns and in-situ in a number of groundwater wells which were thrilled close to leaking sewers.

Results of study: Long-term trickling of sewage through different sand columns as well as in-situ investigations of groundwater from urban underground revealed the following results:

1. 99 – 99.9 % of the aerobic and anaerobic sewage population was eliminated after 1.25 m trickling in sandy soil, leaving a to high residual population of coliforms and enterococci as requested by the European bath water regulation. More than 3000 bacteria/ml of “sand-filtered” sewage reach the groundwater, containing still enterococci and coliforms.
2.  It takes about 20 days in a closed glass coulmn, before methane generation begins. Whereas the number of aerobic bacteria in the biofilm of sand columns decreases, the number of anaerobic bacteria increases on top and with depths. The highest density of anaerobes is found to a depth of 20 - 50 cm. Then carbon sources are no longer available for an unlimited growth of anaerobic bacteria.  
3. In anaerobic sand columns sulfate reduction leads to heavy metal precipitation and no metals are released with the effluent. Desulfovibrio is the predominant sulfate reducing species. 
4. Escherichia is part of the biofilm and is initially present only in the upper part of a sand column. With increasing leakage time it is also found in the biofilm of deeper zones. 
5. Multiresistant sewage bacteria are entering the groundwater and may lead to a distribution of antibiotics resistance gene cassettes. 
6. Several antibiotics in sewage are passing the underground and enter the groundwater, there inducing even more antibiotic resistances.

Trickling sewage may cause an increase of antibiotic resistances within groundwater bacteria by introducing antibiotic-resistant feacal bacteria and non-metabolized antibiotics into the groundwater.  

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