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Vidar Remi Jensen's picture

Vidar Remi Jensen

Professor
  • E-mailVidar.Jensen@uib.no
  • Phone+47 55 58 34 89
  • Visitor Address
    Realfagbygget, Allégt. 41
    Room 
    2040
  • Postal Address
    Postboks 7803
    5020 BERGEN
Thematic areas for master thesis projects

Basically all master’s degree projects are related to either industrial or enzymatic catalysis. Even if the main tool of the research group is quantum chemistry and molecular modeling, it is possible to define combined theoretical/experimental projects and even pure experimental projects within synthesis and testing of catalysts.

 

Project theme: Industrial catalysis

Our studies of catalytic reactions focus on application and refinement of natural gas. Most of the Norwegian natural gas is currently exported and used as a source of heat. However, natural gas is also a valuable raw material for the production of everything from plastics to bioproteins. In the research group we investigate the complete spectrum of the natural gas value chain, from the activation (dehydrogenation) of the alkanes present in the raw natural gas, to the further application of the resulting alkenes in metathesis (to other alkenes, natural products, drugs, fine chemicals and polymers) and polymerization (to plastics). We work to uncover reaction mechanisms as well as to predict and develop new catalysts with desired activity and selectivity. The group is also involved in development of methods and tools for prediction of catalysts.

 

Methods used in projects on industrial catalysis

Methods of computational chemistry

Even if the computational tools used may span from classical (Newtonian) to quantum mechanical descriptions of the chemical systems, our most important methods are those of quantum, in particular density functional theory (DFT). We normally use existing software and programs (e.g., Gaussian and NWChem) to conduct the quantum chemical calculations. In projects on development of tools for prediction of new catalysts we focus on use of genetic algorithms for in silico “Darwinian” development of more active and selective compounds. It is possible to define projects exclusively devoted to method development and programming.

 

Example of title of doctoral thesis involving computational methods:

”Metallofullerenes of the Transition Metals: Theoretical Investigation of Structures and Chemical Properties”

 

Experimental methods

We work with catalysts in which the active centers consist of transition metal atoms bound to one or more organic ligands. Most such organometallic complexes are sensitive to air and moisture and the syntheses are conducted under inert atmosphere (argon), either in glove boxes or by using so-called Schlenk-technique.

 

Example of title of master’s thesis involving both experimental and computational methods:

”Design and Synthesis of Ruthenium based Olefin Metathesis Catalysts”

 

Project theme: Enzymatic catalysis – amino acid hydroxylase

The group focuses on activation of dioxygen in iron-dependent enzymes. More specifically, we focus on investigation of the mechanism of iron-catalyzed hydroxylases, in close collaboration with the group of Prof. Aurora Martinez (Department of Biomedicine). The goal is to use the mechanistic insight in theory-supported development of drugs, i.e., in silico drug design. Development of drugs is important since mutations in the iron-based hydroxylase enzymes are associated with a series of illnesses, among them phenylketonuria and Parkinson’s disease.

 

Methods used in projects on enzyme catalysis

The computational tools may span from classical (Newtonian) to quantum mechanical descriptions of the systems. Hybrid methods in which different parts of the system is described by different approximations (classical or quantum), may also be used. The research group itself is not conducting experiments within enzyme catalysis, but works closely with a group (Prof. Aurora Martinez) that does.

 

Example of title of master’s thesis involving classical mechanics and dynamics:

”Development of Starting Structures for QM/MM Simulations of the Catalytic Domain of Human Phenylalanine Hydroxylase using Molecular Dynamics”.

 

Example of title of master’s thesis involving both quantum chemistry and experimental studies:

”Theoretical and Experimental Vibrational Spectroscopy Studies of (6R)-L-Erythro-5,6,7,8 – Tetrahydrobiopterin and Its Interaction with Phenylalanine Hydroxylase”.

 

Example of title of doctoral thesis involving quantum chemistry:

”Mechanistic Investigation of Aromatic Amino Acid Hydroxylases”.

 

 

Previous master’s thesis projects
  • Design and Synthesis of Ruthenium based Olefin Metathesis Catalysts.
  • Development of Starting Structures for QM/MM Simulations of the Catalytic Domain of Human Phenylalanine Hydroxylase using Molecular Dynamics.
  • Theoretical and Experimental Vibrational Spectroscopy Studies of (6R)-L-Erythro-5,6,7,8 – Tetrahydrobiopterin and Its Interaction with Phenylalanine Hydroxylase.

 

Journal articles
  • Chatterjee, Anamitra; Jensen, Vidar Remi. 2017. A Heterogeneous Catalyst for the Transformation of Fatty Acids to ?-Olefins. ACS Catalysis. 7: 2543-2547. doi: 10.1021/acscatal.6b03460
  • Chatterjee, Anamitra; Eliasson, Sondre H. Hopen; Törnroos, Karl Wilhelm; Jensen, Vidar Remi. 2016. Palladium precatalysts for decarbonylative dehydration of fatty acids to linear alpha olefins. ACS Catalysis. 6: 7784-7789. doi: 10.1021/acscatal.6b02460
  • Hessevik, Julie; Ralte, Lalrempuia; Nsiri, Hajar; Törnroos, Karl Wilhelm; Jensen, Vidar Remi; Le Roux, Erwan. 2016. Sterically (un)encumbered mer-tridentate N-heterocyclic carbene complexes of titanium(IV) for the copolymerization of cyclohexene oxide with CO2. Dalton Transactions. 45: 14734-14744. doi: 10.1039/c6dt01706a
  • Smit, Wietse; Koudriavtsev, Vitali; Occhipinti, Giovanni; Törnroos, Karl Wilhelm; Jensen, Vidar Remi. 2016. Phosphine-based Z-selective ruthenium olefin metathesis catalysts. Organometallics. 35: 1825-1837. doi: 10.1021/acs.organomet.6b00214
  • Throne-Holst, Harald; Vittersø, Gunnar; Barkved, Line Johanne; Jensen, Vidar Remi. 2016. Vi trenger en mer ansvarlig forskning. Forskning.no : nettavis med nyheter fra norsk og internasjonal forskning. Published 2016-04-29.
  • Venkatraman, Vishwesh; Gupta, Mayuri; Foscato, Marco; Svendsen, Hallvard Fjøsne; Jensen, Vidar Remi; Alsberg, Bjørn Kåre. 2016. Computer-aided molecular design of imidazole-based absorbents for CO2 capture. International Journal of Greenhouse Gas Control. 49: 55-63. doi: 10.1016/j.ijggc.2016.02.023
  • Foscato, Marco; Deeth, Robert J.; Jensen, Vidar Remi. 2015. Integration of ligand field molecular mechanics in Tinker. Journal of Chemical Information and Modeling. 55: 1282-1290. doi: 10.1021/acs.jcim.5b00098
  • Foscato, Marco; Houghton, Benjamin J.; Occhipinti, Giovanni; Deeth, Robert J.; Jensen, Vidar Remi. 2015. Ring closure to form metal chelates in 3D fragment-based de novo design. Journal of Chemical Information and Modeling. 55: 1844-1856. Published 2015-09-01. doi: 10.1021/acs.jcim.5b00424
  • Venkatraman, Vishwesh; Foscato, Marco; Jensen, Vidar Remi; Alsberg, Bjørn Kåre. 2015. Evolutionary de novo design of phenothiazine derivatives for dye-sensitized solar cells. Journal of Materials Chemistry A. 3: 9851-9860. doi: 10.1039/c5ta00625b
  • Foscato, Marco; Occhipinti, Giovanni; Venkatraman, Vishwesh; Alsberg, Bjørn Kåre; Jensen, Vidar Remi. 2014. Automated design of realistic organometallic molecules from fragments. Journal of Chemical Information and Modeling. 54: 767-780. doi: 10.1021/ci4007497
  • Foscato, Marco; Venkatraman, Vishwesh; Occhipinti, Giovanni; Alsberg, Bjørn Kåre; Jensen, Vidar Remi. 2014. Automated building of organometallic complexes from 3D fragments. Journal of Chemical Information and Modeling. 54: 1919-1931. doi: 10.1021/ci5003153
  • Heyndrickx, Wouter; Occhipinti, Giovanni; Jensen, Vidar Remi. 2014. Neutral nickel ethylene oligo- and polymerization catalysts: Towards computational catalyst prediction and design. Chemistry - A European Journal. 20: 7962-7978. doi: 10.1002/chem.201304889
  • Occhipinti, Giovanni; Koudriavtsev, Vitali; Törnroos, Karl Wilhelm; Jensen, Vidar Remi. 2014. Theory-assisted development of a robust and Z-selective olefin metathesis catalyst. Dalton Transactions. 43: 11106-11117. doi: 10.1039/c4dt00409d
  • Minenkov, Yury; Occhipinti, Giovanni; Jensen, Vidar Remi. 2013. Complete reaction pathway of ruthenium-catalyzed olefin metathesis of ethyl vinyl ether: kinetics and mechanistic insight from DFT. Organometallics. 32: 2099-2111. doi: 10.1021/om301192a
  • Occhipinti, Giovanni; Hansen, Fredrik Rosberg; Törnroos, Karl Wilhelm; Jensen, Vidar Remi. 2013. Simple and highly Z‑selective ruthenium-based olefin metathesis catalyst. Journal of the American Chemical Society. 135: 3331-3334. doi: 10.1021/ja311505v
  • Sparta, Manuel; Jensen, Vidar Remi; Børve, Knut J. 2013. Accurate metal-ligand bond energies in the (2)-C2H4 and (2)-C-60 complexes of Pt(PH3)(2), with application to their Bis(triphenylphosphine) analogues. Molecular Physics. 111: 1599-1611. doi: 10.1080/00268976.2013.809489
  • Chu, Yunhan; Heyndrickx, Wouter; Occhipinti, Giovanni; Jensen, Vidar Remi; Alsberg, Bjørn Kåre. 2012. An evolutionary algorithm for de Novo optimization of functional transition metal compounds. Journal of the American Chemical Society. 134: 8885-8895. doi: 10.1021/ja300865u
  • Heyndrickx, Wouter; Occhipinti, Giovanni; Bultinck, Patrick; Jensen, Vidar Remi. 2012. Striking a compromise: polar functional group tolerance versus insertion barrier height for olefin polymerization catalysts. Organometallics. 31: 6022-6031. doi: 10.1021/om3000828
  • Minenkov, Yuriy Valerievich; Occhipinti, Giovanni; Heyndrickx, Wouter; Jensen, Vidar Remi. 2012. The nature of the barrier to phosphane dissociation from grubbs olefin metathesis catalysts. European Journal of Inorganic Chemistry. 2012: 1507-1516. doi: 10.1002/ejic.201100932
  • Minenkov, Yury; Singstad, Åsmund; Occhipinti, Giovanni; Jensen, Vidar Remi. 2012. The accuracy of DFT-optimized geometries of functional transition metal compounds: a validation study of catalysts for olefin metathesis and other reactions in the homogeneous phase. Dalton Transactions. 41: 5526-5541. doi: 10.1039/c2dt12232d
  • Heyndrickx, Wouter; Occhipinti, Giovanni; Minenkov, Yury; Jensen, Vidar Remi. 2011. Neutral Nickel Oligo- and Polymerization Catalysts: The Importance of Alkyl Phosphine Intermediates in Chain Termination. Chemistry - A European Journal. 17: 14628-14642. Published 2011-12-16. doi: 10.1002/chem.201101152
  • Jensen, Vidar Remi. 2011. Modeling of chemical reactions and catalysis. META. 3. 19-21.
  • Merle, Nicolas; Törnroos, Karl Wilhelm; Jensen, Vidar Remi; Le Roux, Erwan. 2011. Influence of multidentate N-donor ligands on highly electrophilic zinc initiator for the ring-opening polymerization of epoxides. Journal of Organometallic Chemistry. 696: 1691-1697. doi: 10.1016/j.jorganchem.2011.02.015
  • Occhipinti, Giovanni; Jensen, Vidar Remi. 2011. Nature of the Transition Metal-Carbene Bond in Grubbs Olefin Metathesis Catalysts. Organometallics. 30: 3522-3529. doi: 10.1021/om200181y
  • Occhipinti, Giovanni; Meermann, Christian; Dietrich, Hans Martin; Litlabø, Rannveig; Auras, Florian; Törnroos, Karl Wilhelm; Maichle-Mossmer, Cäcilia; Jensen, Vidar Remi; Anwander, Reiner. 2011. Synthesis and stability of homoleptic metal(III) tetramethylaluminates. Journal of the American Chemical Society. 133: 6323-6337. doi: 10.1021/ja2001049
  • Olsson, Sara Elaine; Martinez, Aurora; Teigen, Knut; Jensen, Vidar Remi. 2011. Formation of the Iron-Oxo Hydroxylating Species in the Catalytic Cycle of Aromatic Amino Acid Hydroxylases. Chemistry - A European Journal. 17: 3746-3758. doi: 10.1002/chem.201002910
  • Olsson, Sara Elaine; Martinez, Aurora; Teigen, Knut; Jensen, Vidar Remi. 2011. Substrate Hydroxylation by the Oxido-Iron Intermediate in Aromatic Amino Acid Hydroxylases: A DFT Mechanistic Study. European Journal of Inorganic Chemistry. 17. 2720-2732. doi: 10.1002/ejic.201001218
  • Heyndrickx, Wouter; Occhipinti, Giovanni; Minenkov, Yury; Jensen, Vidar Remi. 2010. On the nature of the active site in ruthenium olefin coordination-insertion polymerization catalysts. Journal of Molecular Catalysis A: Chemical. 324: 64-74. doi: 10.1016/j.molcata.2010.03.023
  • Olsson, Elaine; Teigen, Knut; Martinez, Aurora; Jensen, Vidar Remi. 2010. The aromatic amino acid hydroxylase mechanism: A perspective from computational chemistry. Advances in Inorganic Chemistry. 62: 437-500. doi: 10.1016/S0898-8838(10)62011-9
  • Olsson, Sara Elaine; Martinez, Aurora; Teigen, Knut; Jensen, Vidar Remi. 2010. Water dissociation and dioxygen binding in phenylalanine hydroxylase. European Journal of Inorganic Chemistry. 3. 351-356. doi: 10.1002/ejic.200900489
  • Minenkov, Yury; Occhipinti, Giovanni; Jensen, Vidar Remi. 2009. Metal–ligand bond strengths of the transition metals. A challenge for DFT. Journal of Physical Chemistry A. 113: 11833-11844. doi: 10.1021/jp902940c
  • Occhipinti, Giovanni; Jensen, Vidar Remi; Törnroos, Karl Wilhelm; Frøystein, Nils Åge; Bjørsvik, Hans-Rene. 2009. Synthesis of a new bidentate NHC–Ag(I) complex and its unanticipated reaction with the Hoveyda–Grubbs first generation catalyst. Tetrahedron. 65: 7186-7194. doi: 10.1016/j.tet.2009.05.095
  • Occhipinti, Giovani; Jensen, Vidar Remi; Bjørsvik, Hans-Rene. 2007. Green and efficient synthesis of bidentate Schiff base Ru catalysts for olefin metathesis. Journal of Organic Chemistry. 72: 3561-3564. doi: 10.1021/jo070164z
  • Occhipinti, Giovanni; Bjørsvik, Hans-Rene; Törnroos, Karl Wilhelm; Fürstner, Alois; Jensen, Vidar Remi. 2007. The first imidazolium-substituted metal alkylidene. Organometallics. 26: 4383-4385. doi: 10.1021/om700590v
  • Occhipinti, Giovanni; Bjørsvik, Hans-Rene; Törnroos, Karl Wilhelm; Jensen, Vidar Remi. 2007. Ruthenium alkylidene complexes of Chelating amine Ligands. Organometallics. 26: 5803-5814. doi: 10.1021/om070219n S0276-7333(07)00219-1
  • Sparta, Manuel; Børve, Knut J.; Jensen, Vidar Remi. 2007. Activity of rhodium-catalyzed hydroformylation: Added insight and predictions from theory. Journal of the American Chemical Society. 129: 8487-8499. doi: 10.1021/ja070395n
  • Graf, Martin; Angermund, Klaus; Fink, Gerhard; Thiel, Walter; Jensen, Vidar Remi. 2006. Site epimerization in ansa-zirconocene polymerization catalysts. Journal of Organometallic Chemistry. 691: 4367-4378. doi: 10.1016/j.jorganchem.2006.01.019
  • Lillehaug, Sindre; Jensen, Vidar Remi; Børve, Knut J. 2006. Catalytic dehydrogenation of ethane over mononuclear Cr(III) surface sites on silica. Part II. C–H activation by oxidative addition. Journal of Physical Organic Chemistry. 19: 25-33. doi: 10.1002/poc.990
  • Loboda, Oleksandr; Jensen, Vidar Remi; Børve, Knut J. 2006. Multiple additions of palladium to C-60. Fullerenes, nanotubes, and carbon nanostructures (Print). 14: 365-371. doi: 10.1080/15363830600665672
  • Occhipinti, Giovani; Bjørsvik, Hans-Rene; Jensen, Vidar Remi. 2006. Quantitative structure-activity relationships of ruthenium catalysts for olefin metathesis. Journal of the American Chemical Society. 128: 6952-6964. doi: 10.1021/ja060832i
  • Sparta, Manuel; Børve, Knut J.; Jensen, Vidar Remi. 2006. Structure and stability of networked metallofullerenes of the transition metals. Journal of Physical Chemistry A. 110: 11711-11716. doi: 10.1021/jp064071h
  • Sparta, Manuel; Jensen, Vidar Remi; Børve, Knut J. 2006. Structure and stability of substitutional metallofullerenes of the first-row transition metals. Fullerenes, nanotubes, and carbon nanostructures (Print). 14: 269-278. doi: 10.1080/15363830600663974
  • Bjørsvik, Hans-Rene; Gambarotti, Cristian; Jensen, Vidar Remi; Gonzaléz, Raquel Rodriguéz. 2005. A novel efficient deoxygenation process for N-heteroarene N-oxides. Journal of Organic Chemistry. 70: 3218-3224.
  • Bjørsvik, Hans-Rene; Occhipinti, Giovani; Gambarotti, Cristian; Cerasino, Leonardo; Jensen, Vidar Remi. 2005. Synthesis of methoxy-substituted phenols by peracid oxidation of the aromatic ring. Journal of Organic Chemistry. 70: 7290-7296.
  • Jensen, Vidar Remi; Graf, Martin; Thiel, Walter. 2005. Unusual temperature effects in propene polymerization using stereorigid zirconocene catalysts. ChemPhysChem. 6: 1929-1933. Published 2005-08-01. doi: 10.1002/cphc.200400581
  • Jensen, Vidar Remi; Koley, Debasis; Jagadeesh, Mavinahalli N.; Thiel, Walter. 2005. DFT investigation of the single-center, two-state model for the broken rate order of transition metal catalyzed olefin polymerization. Macromolecules. 38: 10266-10278.
  • Teigen, Knut; Jensen, Vidar Remi; Martinez, Aurora. 2005. The reaction mechanism of phenylalanine hydroxylase. A question of coordination. Pteridines. 16: 27-34.
  • Jensen, Vidar Remi. 2004. Utvikling og evaluering av ny kollokvieordning i Grunnstoffenes kjemi (KJEM120). UPED-skrift. 2. 57-70.
  • Wendt, R. A.; Angermund, K.; Jensen, Vidar Remi; Thiel, Walter; Fink, Gerhard. 2004. Ethene copolymerization with trialkylsilyl protected polar norbornene derivates. Macromolecular Chemistry and Physics. 205: 308-318. Published 2004-02-03.
  • Jensen, Vidar Remi; Poli, Rinaldo. 2003. Theoretical investigation of the low-energy states of CpMoCl(PMe3)2 and their role in the spin-forbidden addition of N2 and CO. Journal of Physical Chemistry A. 107: 1424-1432. Published 2003-03-06.
  • Jensen, Vidar Remi; Poli, Rinaldo. 2003. Theoretical Investigation of the Low-Energy States of CpMoCl(PMe3)2 and Their Role in the Spin-Forbidden Addition of N2 and CO. Journal of Physical Chemistry A. 107: 1424-1432.
  • Jensen, Vidar Remi; Børve, Knut J. 2002. Reduction of chromium in ethylene polymerization using bis(imido)chromium(VI) catalyst precursors. Chemical Engineering Communications. 542-543.
  • Jensen, Vidar Remi; Børve, Knut J. 2001. A theoretical investigation of bis(imido)chromium(VI) cations as polymerization catalysts. Organometallics. 20: 616-626.
  • Jensen, Vidar Remi; Angermund, K.; Jolly, P.W.; Børve, Knut J. 2000. Activity of Homogenous Cromium(III)-Based Alkene Polymerization Catalysts: The Lack of Importance of the Barrier to Ethylene Insertion. Organometallics. 19: 403-410.
  • Børve, Knut; Espelid, Øystein; Jensen, Vidar Remi. 1998. Structure and thermodynamics of Gaseous Oxides, Hydroxides and mixed Oxo-hydroxides of Chromium, CrOm/(OH)n. Journal of Physical Chemistry A. 102: 10414-10423.
  • Børve, Knut; Espelid, Øystein; Jensen, Vidar Remi; Swang, J.A. 1998. Molecular modeling of metal-catalyzd reactions. Kjemi. 10: 22-27.
  • Jensen, Vidar Remi; Børve, Knut. 1998. An investigation of the quantum chemical description of the ethylenic double bond in reactions. Part II Insertion of ethylene into a titanium-carbo bond. Journal of Computational Chemistry. 19: 947-947.
  • Børve, Knut; Jensen, Vidar Remi; Karlsen, Tor; Støvneng, Jon-Andreas; Swang, Ole. 1997. Evaluation of PM3(tm ) as a geometry generator in theoretical studies of transition-metal based catalysts for polymerizing olefins. Journal of Molecular Modeling. 3: 193-202. Published 1997-04-25.
  • Jensen, Vidar Remi; Børve, Knut. 1997. Quantum chemical investigation of ethylene insertion into the Cr-CH3 bond in CrCl(H2O)CH3+ as a model of homogeneous ethylene polymerization. Organometallics. 16: 2514-2522.
  • Alsberg, B.K.; Jensen, Vidar Remi; Børve, K.J. 1996. The use of multivariate methods in the analysis of calculated reaction pathways. Journal of Computational Chemistry. 17: 1197-1216.
  • Børve, Knut; Jensen, Vidar Remi. 1996. An investigation of the quantum chemical description of the etylenic double bond in reactions. Part I. The electrophilic addition of hydrocloric acid to ethylene. Journal of Chemical Physics. 105: 6910.
  • Jensen, Vidar Remi; Børve, K.J.; Westberg, N.; Ystenes, Martin. 1995. Titanium-Ethylene Complexes Proposed to be Intermediates in Ziegler-Natta Catalysis. Can they be detected through Vibrational Spectroscopy? Organometallics. 14: 4349-4358.
  • Jensen, Vidar Remi; Børve, K.J.; Ystenes, Martin. 1995. The Ziegler-Natta Ethylene Insertion Reaction For a Five-Coordinate Titanium Chloride Complex Bridged to an Aluminium Hydride Cocatalyst. Journal of the American Chemical Society. 117: 4109-4117.
  • Rosenkilde, Christian; Voyiatzis, George; Jensen, Vidar R.; Ystenes, Martin; Østvold, Terje. 1995. Raman spectroscopic and ab initio quantum chemical investigations of molecules and complex ions in the molten system CsCl-NbCl%f-NbOCl%d. Inorganic Chemistry. 34: 4360-4369.
  • Rosenkilde, Christian; Voyiatzis, George; Jensen, Vidar Remi; Ystenes, Martin; Østvold, Terje. 1995. Raman spectroscopic and ab initio quantum chemical investigations of molecules and complex ions in the molten system CsCl-NbCl%f-NbOCl%d. Inorganic Chemistry. 34: 4360-4369.
  • Jensen, Vidar R. 1994. Studier av kjemiske reaksjonsmekanismer på Paragon. MPP-nytt. Mai. 8-9.
Book sections
  • Šoltészová, Veronika; Foscato, Marco; Eliasson, Sondre H. Hopen; Jensen, Vidar Remi. 2015. Evolution inspector: Interactive visual analysis for evolutionary molecular design. Poster abstracts, pages 219-220. In:
    • Chen, Min; Andrienko, Gennady. 2015. Proceedings of the IEEE Conference on Visual Analytics Science and Technology. IEEE. 224 pages. ISBN: 978-1-4673-9783-4.
  • Olsson, Sara Elaine; Martinez, Aurora; Teigen, Knut; Jensen, Vidar Remi. 2010. The aromatic amino acid hydroxylase mechanism: a perspective from computational chemistry. 62, pages 437-500. In:
    • van Eldik, Rudi; Harvey, Jeremy. 2010. Theoretical and Computational Inorganic Chemistry. Elsevier. 500 pages. ISBN: 978-0-12-380874-5.

More information in national current research information system (CRIStin)