Sökning: "substitution"
Visar resultat 21 - 25 av 752 avhandlingar innehållade ordet substitution.
21. Nucleotide Substitution Patterns in Vertebrate Genomes
Sammanfattning : The rates and patterns at which nucleotide substitutions occur vary significantly across the genome sequence of vertebrates. A prominent example is the difference in the rate of evolution of functional sequences versus nonfunctional (neutrally evolving) sequences, which is explained by the influence of natural selection on functional sequences. LÄS MER
22. Meniscectomy, meniscal repair, and prosthetic substitution : Clinical and experimental investigations
Sammanfattning : This study comprising 7 papers is concerned with different treatment of meniscal injuries. The aim was to analyse today's clinical methods and the possibility for prosthetic substitution in the future. Open peripheral meniscal repair was compared with partial arthroscopic meniscectomy in a 7·year follow-up evaluation of 130 patients. LÄS MER
23. The role of wastepaper in the pulp and paper industry : investments, technical change and factor substitution
Sammanfattning : Environmental concerns, both public and private, has resulted in, among other things, an increased wastepaper recovery. The segment of the economy this has had a major impact on is the pulp and paper industry since they are the prime user of wastepaper in the production of paper and paperboard. LÄS MER
24. Computer-Assisted Organic Synthesis. Addition to Carbonyl Carbons and Aromatic Substitution
Sammanfattning : This thesis concerns the computer-assisted modelling of additions to ketones and aromatic substitution, and how this modelling can be used within an existing program for synthesis planning. I include a review of existing computer-assisted organic synthesis (CAOS) programs, and discuss how some of these programs deal with knowledge representation. LÄS MER
25. Quantum Chemical Studies of Aromatic Substitution Reactions
Sammanfattning : In this thesis, density functional theory (DFT) is used to investigate the mechanisms and reactivities of electrophilic and nucleophilic aromatic substitution reactions (SEAr and SNAr respectively). For SEAr, the σ-complex intermediate is preceded by one (halogenation) or two (nitration) π-complex intermediates. LÄS MER