This study investigates pedagogical challenges posed by interdisciplinary courses using a mixed methods case study. Current engineering education literature describes many multidisciplinary and interdisciplinary efforts—curriculum, programs, courses, and projects—but lacks concrete pedagogical strategies appropriate to such efforts. In interdisciplinary courses, students represent a range of majors and often different academic levels. Consequently, they bring different disciplinary prior knowledge as well as different levels of understanding. This lack of common prior knowledge due to horizontal (disciplinary) and vertical (levels) integration creates unique challenges for faculty associated with both course content and instruction method. To address these challenges, this study adopted a mixed methods approach to collect quantitative and qualitative data in an interdisciplinary Green Engineering Life Cycle Analysis course. Data included surveys, observations, and interviews. The surveys addressed students' motivation for enrollment, prior knowledge of Green Engineering, perception of the course, reflections on course content, satisfaction, and content gains. Observations of classroom and team meeting behaviors, along with interviews of students and faculty provide complementary qualitative data. Quantitative analysis of the content knowledge data demonstrates significant gains for eight of ten concepts. Qualitative analysis shows that students also gained awareness of different perspectives from other disciplines. Qualitative analysis also identified key challenges for faculty in interdisciplinary settings: 1) structural issues related with organizing students from different disciplines with conflicting schedules and 2) disciplinary egocentrism of students through their education and training from in-major courses. The data also suggests teaching practices that have the potential to create new interdisciplinary pedagogies. / Master of Science

Manipulating matter at the nanoscale creates materials endowed with unique optoelectronic and physicochemical attributes. Among the noble metals, the properties of gold in "nano" can be manipulated by varying, their shapes and sizes. Gold nanoparticles find several applications in electronics, medicine and environmental reclamation. Emphasis has been on the “green synthesis” of nanogold to mitigate the hazardous implications stemmed from conventional nanogold synthesis. However, it is not known if the in planta synthesis of nanogold particles could be “green engineered” as well for generating desirable sizes and exotic shapes. In the present study, we used inductively coupled plasma (ICP) analysis to determine the species-specific variability, if any, in uptake of gold across taxonomically diverse plant species (alfalfa, cucumber, red clover, rye grass, sunflower, and oregano). Seedlings of these species were grown in half strength Hoagland’s solution supplemented with 100 ppm potassium tetrachloroaurate (KAuCl4) for 15d under controlled growth room conditions. Significant variations were detected in the ability of different plant species in accumulating gold in the root tissues ranging from 500 ppm (ryegrass) to 2500 ppm (alfalfa). Sunflower and oregano translocated significantly higher levels of gold into their aerial tissues compared to other species. This study thus suggested differential abilities of diverse plant species in uptake of gold by roots and its mobilization to aerial parts. For further elucidation of the effects of different growth variables on in planta synthesis of different shapes and sizes of nanogold particles, alfalfa was selected due to its ability to accumulate large quantities of gold in the root tissues. Further, alfalfa was subjected to KAuCl4 (50 ppm) treatment under variable growth conditions (duration of treatment, pH, temperature and light). Temporal analysis revealed that most of the nanogold particles formed within 6 h of treatment and majority fall within the size range of 10-30 nm. Spherical nanogold particles in the size range of 1-50 nm were detected ubiquitously across different treatments. Interestingly though, a noticeable shift was apparent towards the formation of nanogold particles of exotic shapes in response to specific treatments i.e., pH 3.8 (triangular), pH 7.8 (hexagonal), 15°C (rectangular). This study thus provides empirical evidence towards in planta “green engineering” of nanogold particles of exotic shapes and variable sizes. Efforts are now underway to decipher the mechanistic details governing the acquisition, synthesis and mobilization of nanogold particles in a model plant system. Furthermore, testing the efficacy of alternative non-lignified systems (callus and in vitro germinated pollen tubes) for nanogold particle production is of great interest in that in may be conducive for the extraction of nanogold particles.

Sustainability and green engineering are two main concepts considered throughout this study. Sustainability deals with the utilization of renewable and replaceable sugar-based twelve most promising building blocks included in the report prepared by U.S. Department of Energy and green engineering concept is related with the incorporation of environmental performance criteria to chemical process design. Process performance criteria at the conceptual design stage are selected as persistence, bioaccumulation and aquatic toxicity, economical potential of the processes, atom &amp / mass efficiency of the processes and the relationship between Gibbs free energy of reaction values and economical potential. It is observed that bioaccumulation potentials of both the raw materials and products are low. Petrochemical raw materials are more persistent in air than the bio-based ones. The aquatic toxicity of bio-based raw materials is low / whereas some of the petrochemicals are moderately toxic and allyl alcohol and acrylonitrile among the petrochemicals are classified as highly toxic. Bio -based routes are not economically feasible with 2002 market prices. Atom and mass efficiencies of petrochemical reactions for a group of chemicals are higher than bio-based ones due to mostly addition or substitution reactions. Among high number of products, 1,3 propanediol production from glycerol with two microorganisms is analyzed at preliminary design stage. Process performance criteria are selected as material and energy consumption, cooling water requirement, CO, CO2, SO2 and NOX emissions to the atmosphere per unit of 1,3 propanediol production. Klebsiella pneumoniae process requires less cooling water, but it is less energy efficient and causes higher emissions.

The use of natural environmentally benign agents in the treatment of drinking water is rapidly gaining interest due to their inherently renewable character and low toxicity. We show that the common Mexican cactus produces a gum-like substance, cactus mucilage, which shows excellent flocculating abilities and is an economically viable alternative for low-income communities. Cactus mucilage is a neutral mixture of approximately 55 high-molecular weight sugar residues composed basically of arabinose, galactose, rhamnose, xylose, and galacturonic acid. We show how this natural product was characterized for its use as a flocculating agent. Our results show the mucilage efficiency for reducing arsenic and particulates from drinking water as determined by light scattering, Atomic Absorption and Hydride Generation-Atomic Fluorescence Spectroscopy. Flocculation studies proved the mucilage to be a much faster flocculating agent when compared to Al2(SO4)3 with the efficiency increasing with mucilage concentration. Jar tests revealed that lower concentrations of mucilage provided the optimal effectiveness for supernatant clarity, an important factor in determining the potability of water. Initial filter results with the mucilage embedded in a silica matrix prove the feasibility of applying this technology as a method for heavy metal removal. This project provides fundamental, quantitative insights into the necessary and minimum requirements for natural flocculating agents that are innovative, environmentally benign, and cost-effective.

Orientador: Rubens Maciel Filho, Maria Regina Wolf Maciel / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-09T09:35:16Z (GMT). No. of bitstreams: 1 Custodio_AlineFerrao_D.pdf: 2173448 bytes, checksum: 27b046c8dc2de1781ef672eb1c4ab063 (MD5) Previous issue date: 2007 / Resumo: Este trabalho de tese propôs um processo para a produção de acetato de etila através da reação de esterificação do ácido acético com o etanol, utilizando conceitos de intensificação de processos e de Engenharia Verde (Zero Avoidable Pollution com renweable feedstock). A contribuição principal desta pesquisa é a proposta de uma planta conceitual com alta pureza de todas as correntes do processo, o que diminui desperdícios, de modo que o produto indesejado ou os reagentes não convertidos não estejam presentes nas correntes de saída do sistema. No processo proposto, todos os reagentes são de origem renovável. O acetato de etila é um solvente orgânico importante utilizado na produção de vernizes, de tintas, de resinas sintéticas e de agentes adesivos, sendo produzido normalmente, através da reação reversível do ácido acético com o etanol, com ácido sulfúrico com catalisador. O processo deste sistema de obtenção é bastante complexo porque o produto (acetato de etila) não é o componente mais volátil nem o menos volátil no sistema, de modo que a etapa de separação não é fácil de definir. O projeto conceitual proposto inclui um reator de tanque contínuo (CSTR) acoplado a um retificador, um decantador e duas colunas de purificação, para a água e o acetato de etila. O software comercial ASPEN PLUS® foi utilizado para a realização dos estudos do processo proposto através de simulação computacional em estado estacionário, e o simulador ASPEN DYNAMICS® foi utilizado para a simulação dinâmica / Abstract: This work proposes a process for ethyl acetate production via esterification of acetic acid with ethanol using concepts of process intensification and zero avoidable pollution. The main contribution of this work is the high-purity of all process streams, including the wastes ones, so that undesired product or unconverted reactants are not present in any throughput streams. Ethyl acetate is an important organic solvent widely used in the production of varnishes, ink, synthetic resins, and adhesive agents and it is normally produced via reversible reaction of acetic acid with ethanol, with sulfuric acid as catalyst. The process design of such system is complex because the ethyl acetate product is neither the lightest nor the heaviest component in the system, so that the separation stage is not an easy task. The proposed process design includes a continuous-stirred tank reactor (CSTR) coupled with a rectifier, a decanter and two purification columns for water and ethyl acetate. The commercial ASPEN PLUS® software was used to steady state simulation and ASPEN DYNAMICS® was used to dynamic simulation / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

Master of Science / Department of Chemical Engineering / Larry E. Erickson / As our society continues to better prepare itself to address biological, radiological, chemical, and environmental emergencies, there is a need for better and more readily available emergency planning information for program managers and military/business personnel. An online hazardous materials and emergency planning tool for the Environmental Knowledge and Assessment Tool (EKAT: www.ekat-tool.com) would adequately fill that need. The proposed online Emergency Preparation and Green Engineering (EPGE) tool would provide the user with information regarding links to local emergency response teams and resources, guides for developing emergency plans and reports, Hazardous Materials (HAZMAT) training information, case studies to illustrate HAZMAT situations, and the ability to judge the environmental friendliness of chemicals. In this way it will serve as a means of facilitating and educating individuals for best responses in an organized fashion. In order to address their environmental responsibilities, public and private organizations are adopting Environmental Management Systems (EMS). The EPGE tool can be used in conjunction with Environmental Management Systems (EMS) to begin to address sustainability in a more practical setting. Currently the development of a comprehensive tool that identifies environmental, health, and safety concerns along with supplying relevant emergency data would be applicable to any business or organization. This tool will be available as an initial building block for the sustainability of the company. It can be used as a guide to better characterize and solve the environmental issues that could affect any business.

A broad scope analysis of waterjet cutting systems has been developed using thermodynamics, life cycle analysis, and biological system comparison. The typical assessments associated with mechanical design include measures for performance and thermodynamic efficiency. Further analysis has been conducted using exergy, which is not typically incorporated into design practices. Exergy measures the effectiveness of a process with respect to a base state, usually that of the systems surroundings. Comparing Gibbs free energy of biological processes to exergy efficiency has served to illustrate the need for various levels of comparison. Each biological process used in this comparison correlates to a different type of mechanical process and level of complexity. Overall, biological processes display similar properties to mechanical systems in that simpler systems are more energy efficient. In order to determine accurate efficiency and effectiveness values for a mechanical process, in this case waterjet cutting, a set of thermodynamic models was established to account for energy uses. Various output force and velocity models have been developed and are used here for comparison to assess output efficiencies with "no loss" models used as a lossless base. Experimental testing was then conducted using a simple nozzle and a pressure washer with 2 other diameter nozzles. The most energy efficient system used a turbojet nozzle. It was also the most efficient sustained system with energy inputs. However, it had a much lower exergy efficiency compared to the other systems. This implies that it could be significantly improved by more adequately utilizing the energy provided. An effort to assess the green nature of pressurized water systems was done through use of an Economic Input/Output Life Cycle Analysis (EIO-LCA). The EIO-LCA is designed to assess processes for greenhouse gas emissions and total power consumption across the life of a system. Calculations showed that increases in power consumption result in much higher greenhouse gas emissions per unit time than increases in water consumption. Financial cost however showed an opposite trend due to the much greater cost of water with regard to consumption rates in each system. The most "green" system used only a nozzle with no power consumption.

Significant research is ongoing in the world to meet the needs of social and environmental crisis by harnessing wind and solar energy at high altitudes. One such approach is the use of an inflatable High Altitude Aerial Platform (HAAP). In the presented work, such periodically supported beam-like structures are analyzed using various mathematical models primarily modeling them as an equivalent beam using one-dimensional theories. The Euler-Bernoulli Theory (EBT) has been widely used for high aspect ratio beams, whereas the First Order Shear Deformation Theory (FSDT), or the Timoshenko beam theory, considers transverse shear effects and hence is superior in modeling low aspect ratio beams. First, an Isogeometric Analysis (IGA) is conducted using both FSDT and EBT to predict thermal buckling of periodically supported composite beams. Isogeometric analysis overcomes the limitations of the Gibbs phenomenon at discontinuities for a periodically supported beam using a higher order textit{k}-refinement. Next, an Integral Equation Approach (IEA) is implemented using EBT to obtain natural frequencies and buckling loads of periodically supported non-prismatic beams. Ill-conditioning errors were alleviated using admissible orthogonal Chebychev polynomials to obtain higher modes. We also present the prediction of the onset of flutter instability for metal plate and inflatable wing shaped foam test articles analyzed using finite element analysis (FEA). FEA updating based on modal testing and by conducting a geometrically nonlinear analysis resulted in a good agreement against the experiment tests. Furthermore, a nonlinear co-rotational large displacement/rotation FEA including the effects of the pressure as a follower forces was implemented to predict deformations of an inflatable structures. The developed FEA based tool namely Structural Analysis of Inflatables using FEA (SAIF) was compared with the experiments and available literature. It is concluded that the validity of the developed tool depends on the flexibility of the beam, which further depends upon the length of the beam and the bending rigidity of the beam. Inflatable structures analyzed with materials with high value of the Young's modulus and low to medium slenderness ratio tend to perform better against the experimental data. This is attributed to the presence of wrinkling and/or the Brazier effect (ovalling of the cross section) for flexible beams. The presented work has applications in programmable buckling, uncertainty quantification, and design of futuristic HAAP models to help face the upcoming environmental crises and meet the societal needs. / Doctor of Philosophy / In the future, developed countries are projected to face an increase in renewable energy demands due to environmental crises and increasing societal needs for energy due to urbanization. Wind energy, a renewable source, has received increasing attention. Wind farms require large land space and offshore wind energy harvesting is prone to unstable environments. Crosswind kite power is one of the promising and emerging fields where one can harvest energy from the wind farm inaccessible and apparently endless winds at high altitudes. In this dissertation, we present analysis and experiments on investigating complex structures, such as inflatable high altitude aerial platforms (HAAP) by using various mathematical models, primarily modeling them as an equivalent beam using one-dimensional theories. We investigate the effects of internal pressure on such structures, which unlike many other types of applied loads, follow the direction of the deflections. When supported on multiple supports, these structures are more efficient in terms of increased payload capacity due to a better distribution of loads, despite the increased weight penalty. To name a few, there are direct applications of periodic supports in design of bridges and railway sleepers. To avoid violent vibrations or failure, we also investigate the effect of multiple supports on the so-called natural frequency, vibration frequency under absence of applied loads, and buckling loads, instabilities under compression, of such beam-like structures. The presented work will aid in the design of futuristic HAAP models to help face the upcoming environmental crises and meet the energy demands of society due to urbanization.

Sustainability has been heightened to a new level of importance, due to the current global race for commodities and conservation of our environment. Sustainable Buildings are of particular interest since buildings are significant contributors to consumption of resources. Since the inception of the United States Green Building Council (USGBC) in 1993, USGBC has played a key role in providing guidance to the design and construction community in building“green" structures. The Leadership in Energy and Environmental Design (LEED) rating system is an industry accepted standard for the design/construction and measurement of green buildings. Although USGBC provides guidance on performance measurement, a streamlined process of performance tracking and measurement has not been formalized. This research focuses on identifying vital areas of required tracking and measurement; to allow for a systematic analysis of costs and benefits, over the life of sustainable buildings. A case-study based on the recently designed and constructed East Hall LEED-Gold Certified, dormitory building at Worcester Polytechnic Institute (WPI), was undertaken to create and assess a life cycle costs analysis framework. This research is aimed at understanding what the costs of building green at WPI truly are. Life Cycle Cost Analyses of the mechanical, electrical, plumbing and roof components were evaluated to generate percent savings or percent added cost. This research reviewed the various green and non-green costs of construction, consumption, and operations and maintenance costs providing a comparative analysis to leading researchers in the field of costs and benefits of building green.

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