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Phytoremediation: green technology for the clean up of toxic metals in the environment

Gratão,Priscila Lupino; Prasad,Majeti Narasimha Vara; Cardoso,Patrícia Felippe; Lea,Peter John; Azevedo,Ricardo Antunes
Fonte: Brazilian Journal of Plant Physiology Publicador: Brazilian Journal of Plant Physiology
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2005 EN
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The contamination of the environment by toxic metals poses a threat for "Man and biosphere", reducing agricultural productivity and damaging the health of the ecosystem. In developed nations, this problem is being addressed and solved to some extent by using "green technology" involving metal tolerant plants, to clean up the polluted soils. The use of naturally occurring metal tolerant plants and the application of genetic manipulation, should hasten the process of transferring this technology from laboratory to field. Therefore, it is essential to investigate and understand how plants are able to tolerate toxic metals and to identify which metabolic pathways and genes are involved in such a process. Recent advances in knowledge derived from the "omics", have considerable potential in developing this green technology. However, strategies to produce genetically altered plants to remove, destroy or sequester toxic metals from the environment and the long-term implications, must be investigated carefully.

Optimization of electrostatic binding free energy : applications to the analysis and design of ligand binding in protein complexes

Green, David Francis, 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 200 p.; 1949181 bytes; 1948869 bytes; application/pdf; application/pdf
ENG
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45.96%
Electrostatic interactions play an important role in determining the energetics of association in biomolecular complexes. Previous work has shown that, within a continuum electrostatic model, for any given complex there exists a ligand charge distribution which optimizes the electrostatic binding free energy - the electrostatic complement of the target receptor. This electrostatic affinity optimization procedure was applied to several systems both in order to understand the role of electrostatic interactions in natural systems and as a tool in the design of ligands with improved affinity. Comparison of the natural and optimal charges of several ligands of glutaminyl-tRNA synthetase from E. coli, an enzyme with a strong natural requirement for specificity, shows remarkable similarity in many areas, suggesting that the optimization of electrostatic interactions played a role in the evolution of this system. The optimization procedure was also applied to the design of improvements to two inhibitors of HIV-1 viral-cell membrane fusion. Two tryptophan residues that are part of a D-peptide inhibitor were identified as contributing most significantly to binding, and a novel computational screening procedure based on the optimization methodology was developed to screen a library of tryptophan derivatives at both positions. Additionally...

Orbit determination and prediction processes for low altitude satellites

Green, Andrew Joseph
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 518 p.; 26046055 bytes; 26045812 bytes; application/pdf; application/pdf
ENG
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45.96%
by Andrew Joseph Green.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1980.; MICROFICHE COPY AVAILABLE IN ARCHIVES AND AERO.; Vita.; Includes bibliographical references.

High green density metal parts by vibrational compaction of dry powder in three dimensional printing process

Gregorski, Steven Joseph
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 399 p.; 33845592 bytes; 33845349 bytes; application/pdf; application/pdf
ENG
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46.13%
The material properties and dimensional accuracy of metal tooling produced by the Three Dimensional Printing process can be enhanced by increasing the green density of the 3D printed part. Green density is the ratio of metal powder volume to the external volume of the printed part, and is a measure of how tightly packed the powder particles in the printed part are. The central goal of this thesis was to increase the green density of metal parts from the current level of 58% to levels greater than 75%. Two approaches were taken for increasing green density. The first was to utilize bimodal mixtures of metal powders which could be packed to significantly higher densities than the monomodal powders which had been previously used. Three bimodal powder mixtures, with tap densities near 80%, were studied. The second approach was to develop a new powder layering device which could pack these bimodal powders to the tap density during layer creation. New understandings about the relationship between the stresses applied to the powder layer and the resulting packing density changes were required to design this device. Shear cell and unconfined compression tests were performed to characterize the metal powder stress / strain behavior. Particulate stress / strain models...

The effects of carpet dye on the Bagmati River

Green, Hillary Monette, 1981-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 69 leaves; 7319297 bytes; 7319057 bytes; application/pdf; application/pdf
ENG
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45.96%
by Hillary Monette Green.; Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2003.; Includes bibliographical references (leaves 67-69).

View-dependent precomputed light transport using non-linear Gaussian function approximations

Green, Paul Elijah
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 46 p.; 2110289 bytes; 2228407 bytes; application/pdf; application/pdf
ENG
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45.96%
We propose a real-time method for rendering rigid objects with complex view-dependent effects under distant all-frequency lighting. Existing precomputed light transport approaches can render rich global illumination effects, but high-frequency view-dependent effects such as sharp highlights remain a challenge. We introduce a new representation of the light transport operator based on sums of Gaussians. The non-linear parameters of the representation allow for 1) arbitrary bandwidth because scale is encoded as a direct parameter; and 2) high-quality interpolation across view and mesh triangles because we interpolate the average direction of the incoming light, thereby preventing linear cross-fading artifacts. However, fitting the precomputed light transport data to this new representation requires solving a non-linear regression problem that is more involved than traditional linear and non-linear (truncation) approximation techniques. We present a new data fitting method based on optimization that includes energy terms aimed at enforcing good interpolation. We demonstrate that our method achieves high visual quality for a small storage cost and fast rendering time.; by Paul Elijah Green.; Thesis (S.M.)--Massachusetts Institute of Technology...

A lexicographic study of Ulwa

Green, Thomas Michael, 1966-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 297 leaves
ENG
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45.96%
by Thomas Michael Green.; Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Linguistics and Philosophy, 1999.; Includes bibliographical references (leaves 294-297).

Green fluorescent protein as a mechanical sensor; GFP as a mechanical sensor

Muso, Taro M. (Taro Michael)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 141 p.
ENG
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56%
Inquiry into intracellular and cytoskeletal mechanics requires an intracellular mechanical sensor to verify models of sub-cellular structure dynamics. To this end, the green fluorescent protein (GFP) is considered as a mechanical sensor candidate with many desirable characteristics. Implicit solvent molecular dynamics CHARMM simulations demonstrated details inaccessible by AFM and OT methods, such as the linkage dependency of fluorophore environment changes and the energy exchanges between protein components during protein unfolding. Theoretical considerations and in vitro experiments explored the parameters important to GFP conjugation by N-hydroxysuccinimide (NHS) ester chemistry, and the complexities associated with a polymer approach to a controlled distribution of force across fluorescent proteins in a polyacrylamide (PAM) gel.; by Taro M. Muso.; Thesis (S.M.)--Harvard-MIT Division of Health Sciences and Technology, 2007.; Includes bibliographical references (p. 133-141).

Green luxury student housing : a real estate feasibility study

Pace, Matthew E. (Matthew Edward)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 79, [1] leaves
ENG
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45.96%
The primary purpose of this thesis is to estimate the demand for student housing that focuses on upperclass undergraduate and graduate students who typically shy away from dormitory housing. The initial chapters provide a brief introduction to conventional student housing, explain why the market is growing, review the growing sustainability trend and introduce the idea of green luxury student housing. Chicago serves as the test market where more than forty universities currently operate. Methods for financing, demand drivers, and overall feasibility are discussed for relevance to the market. Two examples of recently built student housing projects in Chicago and Boston are reviewed for current trends and components to their success. Research conducted includes interviews with student housing developers, a student housing consultant, academic staff and other project participants. Site visits, available online data and reviews of project documentation supplement this research. The thesis concludes with the expected demand believed to support the newly defined market niche and its potential feasibility.; by Matthew E. Pace.; Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Architecture, 2007.; This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.; Includes bibliographical references (leaves 71-74).

Access to the vote in the 2006 midterm election : evidence from the 2006 Cooperative Congressional Election Study

Green-Atchley, Samantha (Samantha Welch Harrison)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 56 p.
ENG
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45.96%
The 2000 and 2004 U.S. national elections were plagued by problems which caused a significant number of citizens to be effectively denied access to the vote. This paper uses data from the 2006 Cooperative Congressional Election Study (CCES) public opinion poll to measure whether certain electoral problems persisted in the 2006 midterm elections. Of particular concern are whether voters were asked to show photo ID in order to vote, whether voters experienced problems with their registrations upon attempting to vote, what demographic groups experienced these problems most frequently, and what remedies were offered to such voters. Additionally, public opinion on whether all voters should be required to show photo IDs in order to vote and on whether polling stations were well operated in this election is also examined. The data shows that while significant percentages of CCES respondents experienced registration problems when voting and/or were asked to show photo ID before voting almost no respondents were prevented from casting ballots. Respondents showed overwhelming support for measures which would require all voters to show photo ID before voting, though this support varied significantly by party ID. Finally, respondents were overwhelmingly pleased with how their polling stations were operated during this election and very few of them were forced to wait in long lines before voting.; by Samantha Green-Atchley.; Thesis (S.M.)--Massachusetts Institute of Technology...

Carbon-nitrogen bond-forming reactions in supercritical and expanded-liquid carbon dioxide media : green synthetic chemistry with multiscale reaction and phase behavior modeling; Green synthetic chemistry with multiscale reaction and phase behavior modeling

Ciccolini, Rocco P
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 338 p.
ENG
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46.04%
The goal of this work was to develop a detailed understanding of carbon-nitrogen (C-N) bond-forming reactions of amines carried out in supercritical and expanded-liquid carbon dioxide (CO2) media. Key motivations behind this study were the importance of nitrogen-containing compounds in the pharmaceutical and fine chemical industries and a growing commercial interest in utilizing environmentally-friendly syntheses and processing with cost-efficient, green solvents. The thermodynamics and reaction engineering characteristics associated with the synthesis of several model C-N bond-forming reactions were examined both experimentally and theoretically. Operating conditions and engineering correlations were identified that will facilitate process scale-up and potential commercialization of these and other fundamentally-important CO2-based processes. Amine chemistry in CO2-based media was complicated by the facility of nucleophilic amines to react with carbon dioxide to form carbamic acids, which sometimes interfered with desired reaction pathways. Experimental observations and a complimentary ab initio quantum chemical calculation study revealed that carbamic acid formation was suppressed when adding bulky N-substituents to primary amines and when operating at low pressures and/or high temperatures. With a firm understanding of amine-CO2 chemistry...

Lattice mismatched epitaxy of heterostructures for non-nitride green light emitting devices

Mori, Michael James
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 165 p.
ENG
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46.11%
In this project, we implement modern metal organic chemical vapor deposition (MOCVD) technology to fabricate monolithic platforms which integrate traditionally incompatible materials with the ultimate goal of achieving high brightness green to amber light emitting diodes (LEDs) and laser diodes (LDs). Unconventional compositions of aluminum indium gallium phosphide (AlInGaP), with lattice constants less than that of GaAs, offer improved electrical and optical characteristics over commonly used GaAsmatched material. Also, integration of optical III-V material on the CMOS platform has long been a technological goal, and these compositions of AlInGaP are amenable to monolithic integration on the (100) Si platform. In this thesis, we pioneer technology to integrate high quality, novel AlInGaP alloys on III-V substrates (and elsewhere, this technology is successfully extended for III-V integration on (100) Si). We first focus on creating a virtual substrate upon which any lattice constant intermediate to GaAs and GaP is available. Large amounts of lattice mismatch are ultimately relaxed through incremental introduction of strain in compositionally graded epitaxial layers, thus breaking the typical lattice-matched constraint of semiconductor systems. Tensile relaxed gallium arsenide phosphide (GaAsP) graded layers yield virtual substrates with extremely low threading defect densities ([rho]t=104cm-2)...

Enhanced polymeric nanoparticles for gene delivery

Green, Jordan Jamieson
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 228 p.
ENG
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45.96%
The potential of gene therapy to treat disease and improve human health is tremendous. The failure of viral gene therapy clinical trials due to toxicity, immunogenicity, and carcinogenicity has been tragic and strongly motivates a non-viral approach. However, non-viral gene delivery is currently ineffective. Here, we show that polymeric nanoparticles composed of poly([beta]-amino esters) (PBAEs) and DNA can be formulated to be stable in the presence of serum proteins and have high gene delivery without toxicity to human primary cells. The biophysical properties of PBAE/DNA nanoparticles have good correlation to transfection efficacy when tested in the appropriate media conditions. We also show that electrostatic interactions can drive peptide coating of nanoparticles and enable ligand-specific gene delivery. A biphasic efficacy relationship exists for peptide weight ratio, overall charge ratio, and ligand length, with intermediate values of coating being optimal. A balance is required when seeking to design nanoparticles that have reduced nonspecific uptake, but increased ligand-specific uptake. We develop a high-throughput assay to quantify polymer/DNA binding as a gene delivery bottleneck and find that a biphasic relationship exists between polymer/DNA binding constant...

Old standbys, new standards : evaluating LEED-ND through existing models of green urbanism; Evaluating Leadership in Energy and Environmental Design for Neighborhood Developments through existing models of green urbanism

Martin, Sophie C. (Sophie Christina)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 152 p.
ENG
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46.04%
The U.S. Green Building Council, the Congress for the New Urbanism, and the Natural Resources Defense Council are currently developing a rating system aimed at evaluating the environmental sustainability of new neighborhood developments. The system, known as LEEDND (Leadership in Energy and Environmental Design for Neighborhood Developments), will be the first comprehensive set of planning and design standards that has the potential for widespread adoption by the development industry. In the absence of a set of standards like these, planners and developers have traditionally looked to older communities that exhibit well-regarded environmental design as models. Because LEED-ND has the potential to supplant these example as a model for guiding future environmental planning and design endeavors, the extent to which LEED-ND captures the values manifested in earlier models should be evaluated. This thesis applies the LEED-ND standards retroactively to three existing communities that the planning and development professions have held up as good examples of environmentally sensitive design. Rather than using the new rating system to evaluate the developments, the developments themselves are used to evaluate LEED-ND and the degree to which it reflects the goals of traditional ecological planning. While the case studies each score high enough to be considered "LEED Certified" (on a modified version of the LEED-ND standards)...

The Greening of China's Food - Green Food, Organic Food and Eco-Labelling

Paull, John
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Conference paper
EN
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China is rapidly adopting, adapting and developing green technology and ideas. China is now a world leader in organic production and this can have implications for world food production. This paper examines the rapid rise of green food and organic agriculture in China, the multiple motivations that have driven it, and the innovative implementation strategies underpinning it. The first organic export from China was in 1990. The Chinese national organic standard and national organic logo were established in 2005. Thirty eight certifiers now operate in China servicing both domestic and export markets. While “Organic” is still poorly understood in the Chinese domestic market, “Green Food” is well known and readily available. Green Food is a Chinese innovation and dates from 1990. The China Green Food Development Centre was founded in 1992 to oversee the implementation of this food production innovation. Certification for Green Food production involves the regulation of inputs, with the objective of reduced use of pesticides, the oversight of production, and the residue testing of the produce. This Green Food strategy has been used as a “half-way house” between chemical food and organic food production. In 1995 Green Food certification was split into Grade A and Grade AA. It is this bifurcation of Green Food standards that laid the groundwork for the rapid articulation from Green Food certification to organic certification...

Building green infrastructure through urban land conservation : the social and ecological value of dispersed open space in the Boston urban wilds

Kinzer, Kirsten (Kirsten Lee)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 123 p.
ENG
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45.96%
Through an analysis of the thirty-year history of the Boston Urban Wilds, this thesis investigates the ability of distributed urban open spaces to provide social and ecological value to the surrounding community. The capacity of the Urban Wilds to act as system to provide simultaneously ecosystem services, public space and wildlife habitat is examined. The evolving understanding of green infrastructure is used as a lens through which to understand the elements of the Urban Wilds model applicable to other communities. Through this lens, the ability of the Urban Wilds to provide social and ecological value greater than the sum of its individual parts is considered. Reflecting on the tools that have been used to enact Urban Wilds conservation, the tools best suited to preserving the Urban Wilds' social and ecological value are assessed. Drawing from the evolution of the Boston Urban Wilds over the past three decades, this thesis concludes with designation, preservation and stewardship recommendations for other cities and towns considering a similar system of distributed open spaces.; by Kirsten Kinzer.; Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2006.; Includes bibliographical references (p. 118-123).

Cost and benefit of energy efficient buildings

Zhang, Wenying, S.B. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 45 leaves
ENG
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46.14%
A common misconception among developers and policy-makers is that "sustainable buildings" may not be financially justified. However, this report strives to show that building green is cost-effective and does make financial sense today. Though green buildings typically have a higher upfront cost compared to conventional constructions, they do offer benefits that simply built-to-code projects lack. These benefits include cost savings from reduced energy and water use, less waste production, diminished environmental and emissions costs, lower operations and maintenance costs, and enhanced occupant productivity and health. These values range from being fairly predictable (energy and water savings can be recorded over time) to relatively uncertain (productivity/health benefits are somewhat arbitrary and subjective). Based on a 20-year Net Present Value analysis with a 5% real interest rate, a recent study by the California Sustainable Energy Task Force showed the total financial benefits of green design to be $50/ft2 - $75/ft2, depending on the building's level of LEED Certification. This number is over ten times bigger than the average 2% cost premium calculated for the 33 green buildings they analyzed-about $3-5/ft in California.; (cont.) Energy savings alone...

The application of information and incentives as tools to promote green affordable housing development

Geng, Lining, 1976-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 173 p.; 10305592 bytes; 10326903 bytes; application/pdf; application/pdf
EN_US
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46.24%
(cont.) developers to produce more green affordable housing.; This thesis examines development barriers to green buildings, particularly to green affordable housing. Green buildings offer intangible benefits in the form of improved environment and health through better air quality. Certain green features also offer significant life-cycle operating savings. These advantages are particularly valuable for affordable housing projects, where low operating costs are critical to affordability and higher indoor air quality is beneficial to modest-income residents that can rarely affect the quality of their living environment. Furthermore, there are many monetary, regulatory, and technical regulations and incentives in the U.S. to promote green building development. Notwithstanding the above advantages and supports, green affordable housing is not yet standard practice. Information and incentives are identified as two of the most important and easy-to-implement tools to promote green affordable housing development. Examples of available information and incentive mechanisms in the U.S. are briefly presented for the green affordable housing industry. Meanwhile, gaps and dysfunctions in the application of these tools are identified as development barriers. The Upham's Corner Marketplace Redevelopment in Massachusetts is presented as an example of a green affordable housing project. Finally...

Structured financial solutions for green affordable housing projects

Subramanian, Shwetha
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 63 p.; 662733 bytes; 662553 bytes; application/pdf; application/pdf
ENG
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46.17%
Environmentally responsible buildings are increasing gaining recognition in the building industry because they address objectives such as conserving natural resources, improving energy efficiency and indoor air quality and they make more economic sense. Affordable housing and Green buildings in particular combine well together as the goals of both overlap. A joint team comprising of New Ecology Initiatives, the Tellus Institute, LISC Boston and the Green CDC's Initiative is currently investigating the Costs and Benefits of Green Affordable Housing. This thesis builds on the research in progress, by focusing on the financial challenges and opportunities faced by green affordable housing. In an attempt to incentivize green affordable housing, this thesis investigates the capital sources that are available at key stages of the development process and how they can best be allocated to meet the costs and needs that arise at each developmental stage. Specifically, the fiscal sources utilized on two representative projects- one rental project and one homeownership project, were analyzed and solutions were found to restructure these resources to pay for green premiums. Several viable solutions emerged to offset the incremental costs of greening in the early phases of the two projects.; (cont.) But the most significant finding of this thesis was the opportunity for cost savings and enhancement of economic value of Green Affordable housing by capitalizing savings from lowered operating costs. This is a powerful mechanism that has the ability to service more debt on the project and cover costs incurred during the interim stages. This thesis demonstrates that there are several ways of structuring successful financing solutions to meet the objectives of all the participants involved...

Assessing the competency needs in the Green Technology Industry

McMahon, Rosemarie
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 29/04/2011 EN_US
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66.22%
This study reviews the technical and interpersonal competencies of professionals in the Green Technology industry. This industry is one of the fastest growing sectors in Europe. This growth trend is expected to continue and is largely due to global environmental issues and energy requirements. Ambitious European targets to reduce dependency on fossil fuels provide the ideal political framework for the expansion of this industry. In light of this development, an important consideration is the availability of skilled professionals in the workforce. This research examines the competencies of professionals based in Scandinavia (regions of Denmark, Norway and Sweden). Information for this study has been gathered from a number of Green Technology companies. This was managed through a series of interviews, focus group discussions and an online survey. Professionals involved in this study concur that education is invaluable to the development of this sector. Many of these professionals have already acquired university level education in disciplines such as engineering. According to the feedback, engineering skills in the Green Technology sector will continue to be important for the next 5 to 10 years. However, supplementary technical (e.g. project management...