Sökning: "equivalents"

Visar resultat 11 - 15 av 103 avhandlingar innehållade ordet equivalents.

1. 11. Accumulative Charge Separation in Photocatalysis : From Molecules to Nanoparticles

   Författare :Mariia Pavliuk; Jacinto Sá; Leif Hammarström; Gary Brudvig; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Accumulative charge separation; Electron transfer; Plasmon dynamics; Time-resolved spectroscopy; Photocatalysis.; Chemistry with specialization in Physical Chemistry; Kemi med inriktning mot fysikalisk kemi;

   Sammanfattning : Photochemical energy conversion into solar fuel involves steps of light absorption, charge separation and catalysis. Nature has taught us that the effective accumulation of redox equivalents and charge separation are the key steps in sunlight conversion. LÄS MER

3. 12. Control of weldability : Research leading to the development of two new quenched and tempered tool steels

   Författare :Per Hansson; Hannerz Nils Erik; Torsten Eriksson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Materialvetenskap; Materials science; Teknisk materialvetenskap;

   Sammanfattning : The understanding of the hardenability is important in steel development with respect to weldability of steels as well as to the design of quenched and tempered steels.The common way to judge if steel is suitability to welding is the use of a carbon equivalent, which reflects the alloy content to the hardenability of the heat affected zone (HAZ). LÄS MER

4. 13. Amidst the green Metal-catalyzed amide formation from carboxylic acids

   Författare :Helena Lundberg; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis describes novel methods for transition metal-catalyzed transformation of non-activated carboxylic acids to amides. It was found that 2-10 mol% of zirconium(IV) chloride or 10-20 mol% titanium(IV) isopropoxide catalyzed the formation of a range of secondary and tertiary amides in good to excellent yields (61-99%) in THF at 70-100°C, with molecular sieves present as water scavengers. LÄS MER

5. 14. Single and Accumulative Electron Transfer – Prerequisites for Artificial Photosynthesis

   Författare :Susanne Karlsson; Leif Hammarström; Hans-Christian Becker; Devens Gust; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Artificial photosynthesis; Photoinduced charge separation; Electron transfer; Energy transfer; Accumulative electon transfer; Donor-acceptor; Ruthenium; Linear arrays; Chemical physics; Kemisk fysik; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

   Sammanfattning : Photoinduced electron transfer is involved in a number of photochemical and photobiological processes. One example of this is photosynthesis, where the absorption of sunlight leads to the formation of charge-separated states by electron transfer. LÄS MER

7. 15. Lewis acid promoted endocyclic cleavage of glycosides and related acetals

   Författare :Roger Olsson; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; halichomycin; allylation; carbene; hydrogen bond; organozinc; organotitanium; furanosides; organoaluminium; pyranosides; glycosides; stereoselective; endocyclic cleavage; nucleophilic ring opening; ab initio; Organic chemistry; Organisk kemi;

   Sammanfattning : This thesis is a summary of five papers concerning endocyclic cleavage of glycosides and related acetals. Simple lactol ethers undergo endocyclic cleavage to give acyclic chain extended products on treatment with organoaluminium and organotitanium reagents. LÄS MER