Master degree in Physics, Mathematics and Electronics at the University of Amsterdam.
Master thesis: "Magnetic measurement of low-temperature recovery after plastic deformation."
(also published in Solid State Physics in Electronics and Telecommunications, Academic Press Inc., London, 1960, 231.)
Examination professor prof. dr. G. (Gert) W. Rathenau.
Date June 18, 1958.

Doctor degree in Science at the University of Amsterdam.
Thesis: "Lithium drifted p-i-n junctions in silicon".
Promotor prof. dr. G. (Geert) de Vries.
Date November 8, 1967.

Stay as research scientist at the Research and Development Center, Luminescence Branch,
of the General Electric Company, Schenectady, NY, USA.
Host dr. G. (George) D. Watkins.
July - December 1970.

Teacher of course in Solid State Physics at the Faculty of Science, University of Amsterdam.
Years 1977 - 1998.

Teacher of course in Semiconductor Physics and Technology at the Faculty of Science, University of Amsterdam. Years 1974 - 1977, 1986 - 1995.

Teacher of course in General Physics for the Foundation Nutsseminarium. Years 1979 - 1983.

Chairman 12th International Conference on Defects in Semiconductors,
Amsterdam, Netherlands, August 31 - September 3, 1982.

Secretary Daily Board FOM Community Semiconductors (Werkgemeenschap Halfgeleiders),
1987 - 1995.

Secretary of the Division Semiconductors of the Dutch Physical Society.

Introduction of optical spectroscopy in research group Spectroscopy of Semiconductors, 1984.

Co-chairman (with A. Chantre and P. Wagner) of the Symposium on Science and Technology of Defects in Silicon,
European Materials Research Society (E-MRS),
Strasbourg, France, May 30 - June 2, 1989.

Appointment to professor in Semiconductor Physics at the University of Amsterdam. July 1, 1990.

Expansion of the Working Group by one permanent staff member (universitair (hoofd) docent), 1990.

Co-chairman (with F.F. Bekker, J.J.M. Franse, Nguyen Van Hieu and Than Duc Hien) of the International Workshop on Materials Science of Semiconductors and Rare-Earth Based Materials,
Hanoi, Vietnam, October 15 - 26, 1990.

Member International Advisory Board of the International Training Institute for Materials Science (ITIMS), Hanoi, Vietnam, December 1992 - June 1999.

Member Editorial Advisory Board Materials Science Forum, 1996 - 2004.

Member CERN/ISOLDE Scientific Committee, Geneva, Switzerland, May 1996 - May 1999.

Co-chairman (with B. Pajot) of the 7th International Conference of Shallow-Level Centers in
Semiconductors, Amsterdam, July 17 - July 19, 1996.

Seminar in celebration of 25 years of Spectroscopy of Semiconductors.
Guest seminar speakers prof. dr. R. (Ron) Newman, Reading, UK and prof. dr. J.M. (Martin) Spaeth, Paderborn, Germany.
Publication of the volumes: "Spectroscopie van Halfgeleiders", in volumes I, II and III. December 12, 1995.

Formal retirement, June 30, 1999.

Guest research physicist at the Van der Waals-Zeeman Institute of the University of Amsterdam.
Period July 1999 - June 2004.

Recipient of the 2002 IES Silver Medal Award for Physics and Materials Science by the International EPR/ESR Society.
Award presentation and lecture at the University of Poznan, Poland, July 2002.

Founder-board member of the Foundation Urbanus Ouderkerk aan de Amstel, January 20, 2004.
Secretary of the Foundation 2004 - 2010.

Founder-board member of the Foundation Vrienden Vollebregt Orgel Ouderkerk, January 20, 2004.
Secretary of the Foundation 2004 - 2010.
 
Member Probus Amstelveen-Ouderkerk, April 13, 2005.
Member of Board as treasurer years 2006 - 2008.
Member of Board as chairman years 2009 - 2013.

Founder of the Ammerlaan-Beuken Fonds in the Prins Bernhard Cultuurfonds, 2004.

Founder-board member of the Foundation Erfgoed Amstelland, July 2013.
Treasurer of the Foundation 2013 to present.

Founder of the Ammerlaan-Beuken Fonds in Landschap Noord-Holland, 2019.