Finding Neverland in the Netherlands: My Summer in an Art Heritage and Science Wonderland

Clockwise from top left: about to land at Schipol Airport; a scene taken during my daily bike commute to the lab; a private demonstration at De Kat, the only windmill still producing pigment; the Rijksmuseum and IAmsterdam sign

“There are some things you simply cannot prepare for,” I thought as the plane began the final descent over my home for the summer, the Netherlands. This first brush left me in awe– anxious to uncover the layers that make up this country’s unique character and rich past.

I had no idea that bike “traffic” existed, much less that there is a rush-hour for such traffic. I could not have anticipated being inches away from real-life actual Rembrandt paintings on our very first day. It is overwhelming to be in the presence of such revered masterpieces, and to contemplate how the artists of the Dutch Golden Age could achieve such strikingly realistic works. Even after seeing Girl with a Pearl Earring in person, I’m not sure I’ll ever understand how Vermeer was able to capture light in a bottle and apply it to canvas. Being in the center of this art hotspot feels like the luckiest day ever: as if you’d stumbled upon a whole field of four-leaf clovers, bathed overhead by a quadruple rainbow. Only in the Netherlands could I experience so much of the Dutch Golden Age. There have been so many once-in-a-lifetime experiences as I’ve learned about art conservation and Dutch cultural heritage.

The power of science to preserve these pieces is exhilarating. Admittedly, my background is in materials science and engineering, and so it has been eye-opening to be introduced to the art conservation field and its scientific, historical, cultural, and ethical components. I’ve learned it is a far cry from an easy task to preserve art; the endeavor seems quite chaotic when you stop to think of all the variables. What is the paint composition? What is the chemistry of the binders? How thick is each paint layer, and was it allowed to dry before the next layer was painted? What would the painting have looked like at the time of creation? This is just a tiny sample of questions that art conservators, art historians, and scientists must answer together.

As a student in the NU-IRES program, I conduct research at the University of Amsterdam (UvA) and make my own contribution to the art conservation community. My undergraduate research at Rutgers University heavily focused on characterization of polymer composites, and I became particularly interested in rheology. I am fortunate to continue studying rheology at Northwestern University as a graduate student in the Shull Group. Our group works extensively with the quartz crystal microbalance (QCM) to study polymer thin films. QCM is a powerful technique and—depending on film thickness– can be sensitive to mass changes and viscoelastic properties. At Northwestern, I have been using the QCM to investigate the effect of molecular weight on glass transition temperature in polystyrene thin films. A great advantage of the QCM is its portability. After my last final of the academic year, I packed the QCM equipment in a small cereal-sized box and took the lab on the road.

After landing in one of the art capitals of the world, it was time to shift to a material that art conservators and scientists really care about: linseed oil. I am investigating the QCM’s potential to study the early curing stages of this drying oil. My Dutch advisor, Dr. Piet Iedema, and his group have developed computational models to describe the mechanisms occurring in these early stages. I’m interested in developing a QCM experiment to study the changes in mass when a raw linseed oil film is applied to the QCM crystal. Linseed oil is composed of a hodgepodge of fatty acids; namely -linolenic, oleic, and linoleic acid. Atmospheric oxygen molecules react with the unsaturated bonds in these fatty acids and create highly reactive peroxide species, which then initiate a whole cascade of reactions. During these processes, the oxygen absorption corresponds to an increase in mass. The linseed oil also hardens during the cure process. I’m interested in using the QCM to monitor changes in both mass and viscoelasticity. Linseed oil has been more difficult than polystyrene to work with, and my equipment started malfunctioning. Fortunately, my best friend had planned to come visit in mid-July and was able to come with some replacement equipment from the Shull lab. But even with that stroke of luck, there’s always a risk of persistent problems. These various challenges provide great learning opportunities. So while I may not have been able to conduct as many experiments with linseed oil as I had hoped– I am still learning valuable information about QCM troubleshooting, circuits, mechanics, paintings, metal soaps, etc.

I am immensely grateful for the support of Dr. Shull, Dr. Iedema, Dr. Walton, and Dr. Gambardella this summer. Dr. Shull’s advising and troubleshooting help via email and weekly Skype calls has been a real lifeline. I thank him for his encouragement to apply for the NU-IRES program. The time here has been transformative in ways I could not have anticipated, but sometimes it’s fantastic to have your breath taken away.

Art and Science: The Amsterdam Experience

Posing in front of the Rijksmuseum in the famous “I Amsterdam” sign.

My name is Francesca Long and I am just entering into the second year of my PhD in materials science at Northwestern University. I am lucky enough to spend two months this summer in Amsterdam as part of the Cultural Heritage in the Netherlands program: a National Science Foundation (NSF) sponsored International Research Experience for Students (IRES). My undergraduate degree is in Materials Science and I focused in metallurgy, the topic of my graduate research as well. Back in the US, I study cobalt-based super alloys and do a lot of mechanical testing and microscopy to study my samples. Despite this background in metals, I had always had a strong passion and interest in the arts. I did a minor in Classical Studies alongside my bachelor’s degree and was able to take a class that blended art and Materials Science both in my senior year of undergrad and my first year of graduate school. The course I took in graduate school was all about the field of art conservation from the materials science point of view and really opened my eyes to this field. It became quite clear that this was something I was truly passionate about and wanted to be able to be a part of.

My favorite place to eat my lunch: in the Rijksmuseum garden.

I was fortunate enough to have been allowed to come to Amsterdam to get my first real experience in this field of research at the Ateliergebouw Rijksmuseum. My project is focused on the degradation of arsenic sulfide-based pigments. Artists use many layers in their works to achieve their desired final look, however over time the surface can change in appearance. It is well known that arsenic sulfide pigments, specifically Orpiment and Realgar, are very sensitive to light and moisture in the air and within the paint layers and as such they break down over time and can lose their gorgeous yellow and orange hues. I will be using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX) to analyze cross sections thought or known to contain these pigments in order to determine: the presence of orpiment and/or realgar and the composition of the paint layer as a whole. By knowing what else is present, we hope to add further insight into how these rich pigments go through such a dramatic change and lose their vibrant color and turn white or transparent with age. In addition to this, I am working in collaboration with a conservator who is translating paint recipes in order to hopefully pair up the paints we study in cross sections with old treatises to know exactly what recipes an artist used.

The Netherlands has a very strong national pride in their art. Rembrandt’s Night Watch is beloved all around the world but especially here among countless others. It is this dedication as a whole towards preserving their cultural icons that makes the Netherlands the perfect place for this kind of research. It is something people are fiercely passionate about and as such the resources needed to study how best to preserve and protect works of art are readily available. Not only that, but being in the context of the paintings one is studying makes all the difference in the world. I can look at a cross section and see on and online database what painting it came from and where, but to be able to walk across the street into the Rijksmuseum and see that same painting on the wall in it’s full glory is indescribable. It puts the work into perspective and makes it seem all that much more important.

EDX elemental mapping (right monitor) and corresponding SEM image (left monitor) of a cross section from a De Heem still life on a day it was cooperating with me.

I think doing research abroad has so many benefits to simply staying in the US and working with collaborators in different countries. It exposes one to new languages and cultures and allows one to immerse themselves in their work while experiencing all that another country has to offer. The relationships I can form and build on while here will carry on long after I leave the US and open up the doors in terms of future collaborations. It removes the distractions of being at home and allows the science to become the main focus of the summer. This is a wonderful opportunity and one I would highly recommend to anyone with even the slightest thought of wanting to do a program like this.

As with any research project, I quickly learned that things don’t always go to plan immediately. Equipment can break and take time to get working again which is always frustrating. However, when the SEM computer started giving up, it allowed me to attend a conference that was going on at the Ateliergebouw where I heard a lot of interesting talks about different techniques being developed for use by conservators to study their works safely. I have learned more about artistic methods and painting style in the last three weeks than I ever thought possible. I have learned that I really do want to continue working in this field because every day I am excited to go into the lab and do experiments or even to just sit at my desk and read papers about this line of work. I have also learned that the Dutch are far better at speaking English than I am at speaking Dutch (which isn’t saying much as I have only mastered a few words in Dutch so far) and are so welcoming and happy to help and share their own research with me. I never felt like my lack of experience in this field was a hindrance, it only meant that there was that much more for me to learn every day that I am here and for me to continue learning over the weeks to come.

As Interesting As Watching Paint Dry: The Analysis of Twentieth Century Oil Paints

The Er:YAG laser

My name is Samantha Miller, and I am a Colorado State University graduate student researching in Amsterdam as a part of the Cultural Heritage Science Research funded by the National Science Foundation. As a participant in this International Research Experience for Students (IRES), my work is focused on the chemistry of art conservation. I particularly enjoy this field because it brings together both art and science. By unifying the two, this work defies the stereotypical expectation that the two must be in constant rivalry in order to flourish. My Dutch mentor, Dr. Klaas Jan van der Berg, is a senior conservation scientist and has worked closely with me as I apply my background in analytical chemistry to the analysis of twentieth century oil paints.

Although the old adage “as interesting as watching paint dry” sarcastically illustrates the process as passive and mundane, a number of processes are occurring at the molecular level which alter the chemical composition of the paints. Common drying oils such as linseed and safflower oil are mixed with artists’ pigments and later undergo a series of autoxidation reactions in which triacylglycerides form a crosslinked polymer network as the paint dries. The presence of tri-, di-, and mono- glycerides can be monitored using Mass Spectrometry, a powerful technique that separates ions based on their mass-to-charge ratio. By identifying the presence of these different fatty acids, along with other key compounds such as palmitic acid, stearate, linoleic acid, oleic acid, etc., it’s possible to construct some preliminary commentary on the age of the oil paint as well as the conditions in which it aged.

The quadrupole mass spectrometer with the SAWN chip accessory

My favorite part of chemistry is working with the instrumentation. Obtaining the spectra of different oil paints imparts a more poetic end to the passive drying process. By the end of my tenure here in Amsterdam, I hope to demonstrate that reproducible data can be obtained not only using electrospray ionization (ESI) mass spectrometry, but surface acoustic wave nebulization (SAWN) mass spectrometry as well. Just as the name implies, electrospray techniques use differential voltages across directing cones to generate a gentle stream of ions that pass into mass spectrometer, in our case, a quadruople time-of-flight spectrometer. SAWN uses an applied voltage to generate a standing wave whose energy is transferred to the analyte. Once a threshold energy is reached, the analyte is nebulized into a plume which directed into the mass spectrometer. Preliminary tests have shown that SAWN requires much less volume and adds the additional benefit of removing the ever temperamental injection equipment of ESI methods. Eliminating the pumps, capillary tubes, and injection syringes not only lowers the possibility that a faulty part will slow the experiment, but also the probability of introducing contaminants. The techniques differ only in the way the oil paint is ionized, and if SAWN proves to be a successful method, then hopefully the Rijksmuseum will be able to apply this softer and quicker ionization method to future oil paint samples as well.

As glamorous and photogenic as the research experience has been, the most enjoyable part about working at the Rijksmuseum and Amsterdam is collaborating with fellow scientists. Walking through the main hall of the Ateliergebouw or the University Science Park, it’s easy to see that everyone is absorbed in their work. Yet, beneath the lab coats or behind the monitors are people who share a common passion for both art and science. The scientific community here in Amsterdam has a tangible awareness that they are working towards something greater than their own conservation project or publication. Each office and laboratory I pass reminds me of a different gallery in an art museum; Each is littered with vestiges of their specialized field: spectroscopy, spectrometry, rheology, proteomics. Everyone represents a different facet of science through their approach to conservation. It’s humbling to think that together, the individual efforts, failures, and successes somehow combine to let national artifacts live on for a new audience to appreciate and treasure the way we have.

Sitting at the Intersection between Art and Medicine

My name is Gabriela Diaz and I am a 3rd year student at Texas A&M University, Kingsville pursuing a Bachelor of Science in Chemical Engineering. My background in cultural heritage is a research experience (NSF-REU) at the University of North Texas studying X-ray fluorescence (XRF) to characterization 19th and 20th century silver-plated objects from the Dallas Museum of Art. I am here in Amsterdam through the Cultural Heritage Research in the Netherlands, an International Research Experience for Students (IRES) which is sponsored by the National Science Foundation (NSF).

The focus of my summer research is a technique used primarily in the medical sciences but one that is rapidly gaining popularity in the art conservation community: optical coherence tomography (OCT).  This reseach brings me to work most often in the Academic Medical Center under the mentorship of forensic biophysicist Dr. Maurice Aalders.  However , since our primary aim is to use OCT at the Rijksmuseum, I also work with Katrien Keune in their atelier building. The technique operates on semi-transparent surfaces and is most famously used to understand the structure of the eye but has recently been applied in paintings conservation.

My research question explores how light penetrates the surface and stratigraphy of painting varnish layers. The chosen varnishes I will be working with will be dammar and mastic resin. Using OCT we measure the refractive index of different varnish recipes and also visualize how they  appear within layering scenarios. We can also explore which situations give false positives and false negatives in order to take some of the guess work out of OCT analysis.

The Netherlands holds a special place in my heart due to the fact that one of my favorite painters is Johannes Vermeer. One of the theories behind his success is his prodigious use of optics—adapting the camera obscura—in order to “paint with light.” It is certainly a wonderful coincidence that I, too, shall be operating lenses and mirrors to tell a story—though my case is through an interferometer inside the OCT. Studying these methods of art conservation abroad yields the opportunity to gain new perspective on the styles and approaches scientists outside the U.S. take to restore a work of art. Being in the Netherlands also gives me a chance to get to know a bit about the culture of these world-renowned masters as well as admire their beautiful country.

So far I have learned that no matter how well you think you understand something there will always be something unexpected to bring you back to the scientific chase. I never imagined finding myself studying methods to analyze art inside a hospital, and yet as the days pass it makes perfect sense that skills applied in preserving the health of an individual can find some application in preserving the health of a great painting. Everyday brings new questions and new things to image under the scan-head of the OCT. This constant curious thrill as well as the immersion in the energy of the city has made my transition from the states an adventure to remember.