Dr. Guaciara Macedo dos Santos

Research Project Scientist, Keck-CCAMS Group
Earth System Science Department
B321 Croul Hall,
University of California, Irvine
Irvine, CA 92697-3100
Phone: +1 (949) 824-9851 (office)
Phone: +1 (949) 824-3674 (lab)
Fax: +1 (949) 824-3874

Federal Fluminense University, Brazil         General Physics                   B.Sc. 1992
Federal Fluminense University, Brazil         General Physics                   Teacher License 1995
Federal Fluminense University, Brazil         Laser & Spectroscopy          M.Sc. 1995
Federal Fluminense University, Brazil         Apply Nuclear physics          Ph.D. 1999
Australia National University, Australia       Apply Nuclear physics           Postdoc 1999 to 2001


2016-present    Research Project Scientist V, KCCAMS/UCI Facility
2014-2016        Research Project Scientist IV, KCCAMS/UCI Facility
2011-2014        Research Project Scientist III, KCCAMS/UCI Facility
2008-2011        Research Project Scientist II, KCCAMS/UCI Facility
2006-2008        Specialist I, KCCAMS/UCI Facility
2004-2006        Associate Specialist III, KCCAMS/UCI Facility
2002-2004        Associate Specialist I, KCCAMS/UCI Facility
2002-present    Manager of the KCCAMS/UCI Facility
1999-2001        Post-doctoral Fellow on Accelerator Mass Spectrometry technique at the Nuclear Physics Department, Australia National University


• Awarded LABEX OT-Med 2013 (EU$20,000.00), as Senior Advisor – Title: “Revealing the source of carbon occluded in phytoliths (phytC): potential implication concerning the role of plant Si cycling on carbon cycling” submitted by Dr. A. Alexandre (PI) (
• Awarded NSF grant #EAR-1144888 (US$ 431,439) Principal Investigator, 2012-2015 (extended to 2017) – Is carbon biosequestration by plants feasible? Revealing the source of carbon embedded in phytoliths by using isotope analyses (d13C and 14C measurements) and nanoparticles.
• May to November, 2001 – Bridging Post-doctoral Fellow – ANU, Canberra, Australia – granted by the Institute of Advanced Studies, Research School of Physical Sciences and Engineering, ANU, Australia
• 1999-April,  2001 – Post-doctoral Fellow – ANU, Canberra, Australia – granted by the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazil.


• Characterization of CO2 emission sources.
• Isotopic analyses on carbon occluded in biogenic structures.
• Study of source partitioning of soot-black carbon.
• Tree-ring/14C crossdating to validate tree species and to expand the SH time-scale calibration curve.
• Radiocarbon analyses of purified compounds – lignin phenols in rivers, and phospholipid fatty acids, alkanes and black carbon in oceanic sediments;
• Year-of-death determinations and dietary analyses using Isotope measurements;
• Ultra-small graphite samples and its applications;
• Carbon in the oceans: Tracing natural processes with rare isotopes, Southern California coast.
• Quality control on graphite sample preparation for AMS measurements: background improvements, precision and reproducibility on regular and ultra-small samples;
• Accelerator Mass Spectrometry (AMS) operation, developments and applications.
• Ion-source development for AMS measurements;
• Supervision of 14C-AMS sample preparation for numerous students, pos-docs and professionals from UCI and outside visitors.
• Supervision and consultation on 14C-AMS sample preparation procedures and laboratory set up with numerous laboratories.


1. Outreach (2004-present) – to the public: Instructor for the Summer 14C Short course at ESS/UCI); Facility chaperon to the following programs: Santa Ana and Pacific High School Students, Society for Advancement of Chicanos and Native Americans in Science (SACNAS), FOCUS Summer Teacher Training Institute, and American Indian Summer Institute and the California State Summer School for Mathematics and Science (COSMOS); – to the research community: Worldwide consultant of 14C-AMS facilities and procedural protocols (listed at;
2. Invited speaker to: the International Symposium of the Peopling of the Americas, Piaui, Brazil, 2006; Graphitization Workshop session (in the 20th Radiocarbon Conference), Hawaii, 2009; the NOSAMS/CSRA Workshop at WHOI, Cape Cod, USA 2010; the International Workshop on Small Scale 14C Analysis (keynote), ETH Zürich, Switzerland, 2011; the IX LASNPA, Ecuador, 2011; Department lecture series at CEREGE, Aix en Provence, France, 2012; the XVIII Escola de Verão Jorge André Swieca de Física Nuclear Experimental, UFF, Brazil, 2014; Geoscience Department (lecture), UFMG, Brazil, 2015; and 10th IMPR (keynote), Aix en Provence, France, 2016;
3. Professional affiliations: Tree ring society, American Geophysical Union, Physical Society of Brazil, and Phytolith society; and Reviewer for: Radiocarbon Journal, Quaternary Geochronology, Rapid Communications in Mass Spectrometry, Nuclear Instruments and Methods, The Science of the Total Environment, and NSF (proposals);
4. Co-mentoring of the – REU summer program: In 2012 (John Kearney with Prof. Dr. Claudia Czimczik, ESS/UCI), and in 2014 (Ms. Jessica Sanches with Prof. Dr. Eric Potman at the Department of Chemistry/UCI); – ESS/UCI Senior Thesis program: In 2014 (Ms. Araks Harutyunyan with Prof. Dr. Claudia Czimczik, ESS/UCI), 2009 (Ms. Karla Acaylar with Prof. Dr. Katheleen Johnson, ESS/UCI), 2008 (Ms. Elisa Hinger with Prof. Dr. Ellen Druffel, ESS/UCI); and – PhD Candidates from the Brazilian “sandwich” program: In 2014 (Dr. Fabiana Oliveira With Prof. Dr. Kita Macario, UFF/Brazil).
5. Scientific Advisory Panels and Conference Organization: The 12th Accelerator Mass Spectrometry (AMS) Conference, Wellington, New Zealand, 2011; 6th 14C and Archaeology Symposium, Paphos, Cyprus, 2011; the 22nd 14C Conference, Dakar, Senegal, 2015, and the 24th Conference on Application of Accelerators in Research and Industry (CAARI), Texas, USA, 2016; the 14th Accelerator Mass Spectrometry Conference, Ottawa, Canada, August 14-18, 2017 (upcoming event); and the 2nd International Radiocarbon in the Environment Conference (REII-2017) to take place between 3-7 July, 2017, in the Hungarian Academy of. Sciences, Debrecen, Hungary (upcoming event).


Organizer and associate in Instruction of the Summer UCI short course – “The use of Radiocarbon in Ecology and Earth System Science”. Assisted in instruction for 14C – AMS sample preparation procedures of carbonaceous raw materials and, AMS system operation and analyses of data (2014, 2011, 2009, 2007, 2006, 2005 and 2004).

· Student Lab and Specialist assistants:

Nina Aranas (2012-2014), Dina Saleh (2011-2014), Shari Bush (May 2011–2013), Hector Martinez De La Torre  (2010-2013), Kimberly Padua (2010-2012), Kaelyn Orsmby (2009-2011), Jigna Patel (2009-2011), Nathan Yee (2009-2010), Shenil Patel  (2008-2009), Kelly McKnight (2008), Denis Tauz (March 2007-2009), Christy Loo (March 2007-2009), Elise Hinger (2005-2009), Rachel B. Moore (2004-2008), Bita Hirsa  (August of 2006-January 2007), Robert K. Beverly (2004-2006), Sami Rifai (2004-January of 2006), Diana Hsueh (2003-2004), Susana E. Gonzalez (summer of 2003), Maya  Mazon (2002-2005), Kevin C. Druffel-Rodriguez (2002-2003), Shahla Ali (2002-2003) and Shaun Evola (2002).
· Research Associate Specialist: Will Beaumont (2007-2010)
· Junior Associate Specialist: Robert K. Beverly (2006-2011)
· Research Associate Specialist: Dr. Dachun Zhang (2005-2007)


For a complete list check the links above
Scholar h-index=27, citations= 2429 on January  2017