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Decision support tools for environmentally conscious chemical process design

Cano Ruiz, José Alejandro, 1969-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 599 p.; 16584894 bytes; 16584611 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
770.7721%
The environment has emerged as an important determinant of the performance of the modern chemical industry. Process engineering in the 21st century needs to evolve to include environmental issues as part of the design objectives, rather than as constraints on operations. A frequently cited objection to the use of quantitative indicators of environmental performance in product and process design is that the underlying data are too uncertain for the numbers to have any real meaning. This thesis demonstrates that explicit incorporation of uncertainties allows bounds to be established on the confidence of decisions made on the basis of uncertain indicators. The examples provided show that large uncertainties in indicators used to assess environmental performance do not necessarily imply uncertainty in decision-making. A series of computer-aided decision making tools have been developed to decrease the barriers to the use of environmental valuation functions in routine design activities. These tools include: uncertainty propagation of relative performance measures, a spreadsheet-based fate, transport and exposure model for chemicals, an information content chart for assessing the quality of uncertain indicators, a screening procedure to identify the most important structural and parametric uncertainties in multimedia exposure models...

Metabolic engineering analysis of post-burn hepatic hypermetabolism

Lee, Kyongbum, 1972-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 193 p.; 14005318 bytes; 14005075 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
770.3114%
Metabolic engineering refers to the directed improvement of product formation or cellular properties through the modification of specific biochemical reactions or introduction of new ones with the use of recombinant DNA technology. It has been used to investigate and modify intermediary metabolism in a variety of microbial organisms of biotechnological interest. An emerging area of application for metabolic engineering is medicine, in particular the study of metabolic disorders, where analysis and manipulation of metabolic pathways have obvious relevance. Central to metabolic engineering is the notion that metabolism results from the concerted and coordinated activities of biochemical pathways connected through shared intermediates in the form of common reactants, products, and catalysts. According to this "metabolic network" concept, an enhanced understanding of metabolism and cellular function is obtained by considering the component biochemical reactions together, rather than individually. In this light, this thesis work was motivated by the idea that the application of metabolic engineering analysis to biological systems relevant to human disease has the potential to provide valuable insight into the biochemical underpinnings behind metabolic disorders. In the present dissertation...

Acoustic emulsions of liquid, near-critical carbon dioxide and water : application to synthetic chemistry through reaction engineering

Timko, Michael T., 1974-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 2 v. (372 leaves); 18039811 bytes; 18039610 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
771.66805%
Supervised by The need to eliminate hazardous solvents, such as methanol, toluene, and dichloromethane, in specialty and pharmaceutical chemical synthesis applications has motivated the development of alternative approaches. Because of its environmental compatibility, low cost, and favorable physicochemical properties, supercritical carbon dioxide (scCO2) has been actively considered to replace conventional hydrocarbon solvents. Progress towards this objective has been impressive, for example scCO2 is used as a selective extraction solvent in several commercial processes. By comparison, development of scCO2 as a reaction solvent has been much less successful due to its limited solvation power. Furthermore, the rates of reactions conducted in scCO2 tend to be slower than and their selectivities are comparable to those observed in hydrocarbon solvents. This research focused on development of water/carbon dioxide biphasic reaction systems as an engineering solution to increase reaction rates and manipulate selectivity while preserving environmental compatibility of scCO2. Emulsification by power ultrasound was selected as an additive-free means to bring near-critical liquid carbon dioxide and water into intimate contact and increase interphase transport. With this approach...

Initiated chemical vapor deposition of polymeric thin films : mechanism and applications

Chan, Kelvin, Ph. D. Massachusetts Institute of Technology
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 166 leaves; 8940994 bytes; 8947975 bytes; application/pdf; application/pdf
ENG
Relevância na Pesquisa
772.50195%
Initiated chemical vapor deposition (iCVD) is a novel technique for depositing polymeric thin films. It is able to deposit thin films of application-specific polymers in one step without using any solvents. Its uniqueness of in situ surface polymer synthesis distinguishes iCVD from conventional processes such as spin-on deposition and plasma-enhanced chemical vapor deposition. It allows engineering polymers to be made with specific microscale properties translating to well-defined macroscale behaviors. In this thesis work, two application-specific polymers based on poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(cyclohexyl methacrylate) (PCHMA) were synthesized using iCVD. PHEMA thin films with specific degrees of cross-linking leading to well-defined structural, thermal, wetting, and swelling properties were made in a single vacuum step by simply adjusting chamber conditions. Cross-linked PCHMA thin films were synthesized for use as sacrificial layers for microfabrication. Such films of engineering polymers cannot be made using conventional methods. A study of the polymerization mechanism was included to serve as a groundwork for increased understanding of iCVD as a thin- film deposition method.; (cont.) Growth rates and molecular weights...

Development of systematic and combinatorial approaches for the metabolic engineering of microorganisms

Alper, Hal (Hal Samuel)
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 261 p.
ENG
Relevância na Pesquisa
770.7996%
Explorations and optimizations through the genomic space are a daunting undertaking given the complexity and size of the possible search space. To approach this problem, systematic and combinatorial approaches were employed for the engineering of cellular phenotype in Escherichia coli. Initially, a computational method based on global cellular stoichiometry was employed to identify single and multiple gene knockout targets for lycopene production in E. coli. These targets led to substantial increases in lycopene production, but were limited in scope due to the nature of these models. Therefore, these approaches and targets were complemented with combinatorial searches to identify unknown and regulatory targets. When combined, these searches led to further increases of lycopene production and allowed for the visualization of the resulting metabolic landscape. A more exhaustive search was conducted in the background of eight genotypes which resulted in the formulation of the gene knockout search network. This network enables the investigation into how phenotype optimization is biased by search strategy.; (cont.) Collectively, these results demonstrated that despite the complexity and nonlinearity of genotype-phenotype spaces, most of the significant phenotypes were controlled and regulated by a small subset of key "gateway" nodes. Often...

Chemical engineering education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical engineering education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical engineering education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical engineering education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //Fall 2011 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //Fall 2012 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //2014 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //2014 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //2014 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Chemical Engineering Education; Chem. eng. educ.; CEE

American Society for Engineering Education -- Chemical Engineering Division
Fonte: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn ) Publicador: Chemical Engineering Division, American Society for Engineering Education; Chemical Engineering Division, American Society for Engineering Education ( Storrs, Conn )
Tipo: Artigo de Revista Científica Formato: v. : ill. ; 22-28 cm.
Publicado em //2014 ENGLISH
Relevância na Pesquisa
974.60125%
(Citation/Reference) Chemical abstracts; (Additional Physical Form) Also issued online.; (Dates or Sequential Designation) 1960-June 1964 ; v. 1, no. 1 (Oct. 1965)-; (Numbering Peculiarities) Publication suspended briefly: issue designated v. 1, no. 4 (June 1966) published Nov. 1967.; Title from cover.; Place of publication varies: Rochester, N.Y., 1965-1967; Gainesville, Fla., 1968-

Application of mixed-integer programming in chemical engineering

Pogiatzis, Thomas
Fonte: University of Cambridge; Department of Chemical Engineering and Biotechnology Publicador: University of Cambridge; Department of Chemical Engineering and Biotechnology
Tipo: Thesis; doctoral; PhD
EN
Relevância na Pesquisa
870.7721%
Mixed-Integer Programming has been a vital tool for the chemical engineer in the recent decades and is employed extensively in process design and control. This dissertation presents some new Mixed-Integer Programming formulations developed for two well-studied problems, one with a central role in the area of Optimisation, the other of great interest to the chemical industry. These are the Travelling Salesman Problem and the problem of scheduling cleaning actions for heat exchanger networks subject to fouling. The Travelling Salesman Problem finds a plethora of applications in many scientific disciplines, Chemical Engineering included. None of the mathematical programming formulations proposed for solving the problem considers fewer than O(n^2) binary degrees of freedom. The first part of this dissertation introduces a novel mathematical description of the Travelling Salesman Problem that succeeds in reducing the binary degrees of freedom to O(nlog2(n)). Three Mixed-Integer Linear Programming formulations are developed and the computational performance of these is tested through computational studies. Sophisticated methods are now available for scheduling the cleaning actions for networks of heat exchangers subject to fouling. In the majority of these...