Why having your head in the clouds could be a really good thing

The ATMOS research group in the NANOMO unit, led by Nønne Prisle, Associate Professor at the University of Oulu, are trying to find out what kind of chemistry is happening in cloud droplets and tiny nanometer-sized aerosol particles in the atmosphere. This knowledge could eventually, hopefully, give us more accurate theoretical models to understand the ongoing climate change.
– The only thing that can halter climate change is to stop emitting CO2. Nønne Prisle is very, very clear on that. Even so, she says, if we want to take any other step to try to counter climate change, we really need to know what’s going on in the clouds since these processes could be quite critical.
The ATMOS team are using the beamline HIPPIE at MAX IV being so-called commissioning experts, which means that the experiment is done both to provide useful data but also to verify the capacity and capability of the beamline experimental station.

>Read more on the MAX IV Laboratory website

Image: From left to right: Robert Seidel, Helmholtz Zentrum Berlin; Nønne Prisle, Kamal Raj and Jack Lin, University of Oulu at the HIPPIE beamline.

Capturing protein motion at FemtoMAX

Your body contains a large variety of different proteins. They are big, complex molecules with diverse functions, from transporting oxygen in your blood to making your muscles contract.

Many proteins change their shape and move as they perform their task. A research team from the University of Gothenburg recently visited the beamline FemtoMAX to develop a method for studying moving proteins. They use electric fields to stimulate motion of the proteins in a sample while imaging them with the X-ray beam.
To study how proteins move, we need something to nudge them and then image them after they have changed position. Certain proteins are activated by light and in that case, the researchers can hit them with a laser pulse to provoke the motion. However, that is far from always the case. In the method being developed by the Gothenburg team, the proteins are instead subjected to an electric field that make them move.
The field is synchronized to the short, femtosecond scale (10-15 s) X-ray pulses delivered at beamline FemtoMAX. Each X-ray pulse hitting the sample is like taking a photograph using extremely short shutter speed, just like trying to get sharp images of players on a football field. The X-ray pulses at FemtoMAX are short enough to let the researchers capture the instantaneous position of the protein. By varying the time between the electric field and the X-ray pulse they can see different stages of the movement and even put the frames together as a movie of the protein motion.

>Read more on the MAX IV Laboratory website

HIPPIE provides a closer look at water filtration

Clean fresh water is a scarce resource. Areas of the world suffering from drought have to filter the salt out of seawater to make it drinkable. In other areas, the water may instead have a high content of toxic compounds, such as arsenic.
If you think about a water filter as a kind of strainer with tiny holes through it, you would assume that since it does a pretty good job of filtering out the small ions of normal table salt, sodium, and chloride, from seawater it would work even better for the larger arsenic compounds. This is however not the case when it comes to desalination – the technology for producing fresh water from seawater; quite the opposite actually. While sodium and chloride are removed effectively, other, much larger contaminants pass through the filtration materials that are typically used. That indicates there must be another mechanism at work here.

>Read more on the MAX IV Laboratory website

Students use AI for sample positioning at BioMAX

The samples at BioMAX beamline are very sensitive biomolecule crystals. It could, for example, be one of the many proteins you have in your body. They only last for a short time in the intense X-ray light before being damaged and needs to be placed exactly right before the researchers switch on the beam. In their masters’ project, Isak Lindhé, and Jonathan Schurmann have used methods of artificial intelligence to train the computer how to do it.

Hundreds of thousands of proteins
You have hundreds of thousands of different proteins in your body. They do everything from transporting oxygen in your blood to letting your cells take up nutrients after you’ve eaten or make your heart beat. And when things go wrong, you get prescribed medication. The pharmaceutical molecules connect to the proteins in your body to change how they work. To develop new pharmaceuticals with few side effects, the researchers, therefore, need to understand what different proteins look like in detail.

A tedious task
To get high-quality data from a sample it needs to be correctly positioned in the X-ray beam. The conventional model for finding the right position is to scan the sample in the beam to optimize the position. At MAX IV, the X-ray light is very intense, which is good because smaller crystals can be used. But at the same time, very often the sample can’t be scanned in the beam since it would be damaged long before the right position is found. The researchers, therefore, have to perform the rather tedious task of positioning it manually.

>Read more on the MAX IV Laboratory website

First commissioning results for insertion devices published

The intense X-ray light for each of the MAX IV beamlines is generated when fast electrons fly through an array of magnets, placed in a so-called insertion device.

In a recent report, our insertion device team present the commissioning results for the first nine of these beamline specific instruments.
At synchrotrons like MAX IV, we accelerate electrons to velocities close to the speed of light. The electrons are injected into storage rings where they travel turn after turn inside a vacuum tube, guided by the strong forces of hundreds of carefully tuned magnets. At certain places along the electron path, the magnets are arranged in arrays called insertion devices that make the electrons wiggle from side to side as they fly through. When the electrons perform this motion, they emit energy in the form of intense X-rays. Each beamline needs its dedicated insertion device, built to produce X-rays optimised for the measurement techniques performed there.
The insertion device team have now published the first commissioning results. At the time the report was written, twelve insertion devices were installed, and nine successfully commissioned to deliver according to specifications. Six of them have been built in-house, and two are transferred from the old MAX-lab and refurbished. The remaining insertion devices come from Hitachi and our French synchrotron colleague SOLEIL.

>Read more on the MAX IV Laboratory website

Towards upscaling the production of graphene nanoribbons for electronics

Two-dimensional sheets of graphene in the form of ribbons a few tens of nanometers across have unique properties that are highly interesting for use in future electronics.

Researchers have now for the first time fully characterised nanoribbons grown in both the two possible configurations on the same wafer with a clear route towards upscaling the production.
Graphene in the form of nanoribbons show so called ballistic transport, which means that the material does not heat up when a current flow through it. This opens up an interesting path towards high speed, low power nanoelectronics. The nanoribbon form may also let graphene behave more like a semiconductor, which is the type of material found in transistors and diodes. The properties of graphene nanoribbons are closely related to the precise structure of the edges of the ribbon. Also, the symmetry of the graphene structure lets the edges take two different configurations, so called zigzag and armchair, depending on the direction of the long respective short edge of the ribbon.

See some video interviews and the entire article on the MAX IV website

Biological material discovered in Jurassic fossil

Ichthyosaurs were reptiles that roamed the Jurassic oceans 180 million years ago. They are extremely well studied and the form will probably be instantly recognisable from museums and textbooks. They resemble modern toothed whales such as dolphins and this similarity led researchers to hypothesise that the two creatures had similar strategies for survival in the marine environment. However, until now, there was little evidence to support this hypothesis. The research team led by Lund researcher Johan Lindgren went on the search for biological material within fossils to help solve this puzzle. After a lot of preparation in the lab and traveling around the world to perform experiments, they discovered that the fossil contained remnants of smooth skin and subcutaneous blubber. This is compelling evidence that the Ichthyosaurs were indeed warm-blooded and confirms the previous hypothesis. Lindgren showed visible delight when he described how you could see that the 180-million-year-old blubber was indeed visibly flexible after treatment in his laboratory.

>Read more on the MAX IV Laboratory website

Image: MAX IV’s Anders Engdahl was part of a team that published a landmark study about biological tissue found in a Jurassic fossil. The work published this week in Nature is one of the most comprehensive studies of its kind and sheds new light on the life of a prehistoric sea creature.

The quest for better medical imaging at MAX IV

Advances in the world of physics often quickly lead to advances in the world of medical diagnostics. From the moment Wilhelm Röntgen discovered X-rays he was using them to look through his wife’s hand.

A lot of the physics principles at the foundation of MAX IV are also at the foundation of medical imaging technologies such as nuclear magnetic resonance imaging, x-ray computed tomography and positron emission tomography.
Positron emission spectroscopy is more commonly known as PET imaging. It’s a method used to study metabolic processes in the body as a research tool but also to diagnose disease. An important use today is in the diagnosis of metastases in cancer patients, but it can also be used to diagnose certain types of dementia.

In PET, a positron-emitting radionuclide is injected into a patient and travels around the body until it accumulates somewhere, depending on the chemical composition. For example, the fluorine-18 radionuclide when bound to deoxyglucose accumulates in metabolically active cells which is useful for finding metastases. The radionuclide is unstable and emits positrons which is the antimatter equivalent of an electron. When a positron and an electron inevitably meet, they annihilate one another, producing two pulses of gamma radiation traveling in opposite directions. By placing a detector around a patient, it is possible to measure the gamma radiation and convert the signal into something that can be more easily measured. These detectors are made up of materials known as scintillators which take high energy radiation and emit lower energy radiation that can be detected using fast photodetectors – photomultiplier tubes.

>Read more on the MAX IV Laboratory website

 

The human behind the beamline

Happy Birthday, Felix Bloch – 23rd October 1905

Felix Bloch was born on this day (23rd October) in 1905 in Zürich, Switzerland. He got a Ph.D. in 1928 studying under Werner Heisenberg. In his thesis, he established the quantum theory of solids describing how electrons moved through crystalline materials using Bloch waves. The phenomena he described are observed today using the technique ARPES which is carried out at the Bloch beamline at MAX IV.

>Read more on the MAX IV Laboratory website

Image: Detail of a Max Bloch illustration. To discover the entire illustration click here.
Credit: Emelie Hilner.

The search for clean hydrogen fuel

The world is transitioning away from fossil fuels and hydrogen is poised to be the replacement.

Two things are needed if we are to make the transition to a low carbon, “hydrogen economy” they are clean and high yielding sources of hydrogen, as well as efficient means of producing and storing energy using hydrogen.

Hydrogen powered cars are the perfect case study for how a hydrogen-fuelled future would look. While they work and show a great deal of promise, the best examples of hydrogen being used in fuel require very clean sources of hydrogen. If the source of hydrogen is mixed with contaminants like carbon monoxide, the efficiency of the fuel goes down and causes downstream problems in the fuel cell.

A team from KTH led by Jonas Weissenrieder is visiting MAX IV this week to try and solve this exact problem, how can we generate clean hydrogen for fuel cells? The team is working on a process to catalyse the oxidation of carbon monoxide, which adversely affects fuel cell performance, to harmless carbon dioxide. The catalysis reaction must be selective, and not affect the hydrogen gas that could be oxidised to water which is not great for running car engines.

>Read more on the MAX IV Laboratory website

Acid-base equilibria: not exactly like you remember in chemistry class

Work published in the Royal Society of Chemistry with the support of the Helmholtz Association through the Center for Free-Electron Laser Science at DESY, MAX IV Laboratory, Lund University, Sweden,  European Research Council (ERC) under the European Union’s Horizon 2020 and the Academy of Finland.

Remember doing titrations in chemistry class? Adding acid drop-by-drop to the beaker and the moment you took your eye off it the solution completely changed colour.
We learned in chemistry that by doing this titration, we were actually affecting an important equilibrium in the beaker between acids and bases. This equilibrium was first described at the turn of the 20th century by American biochemist Lawrence Henderson and modified by Karl Hasselbalch giving us the Henderson-Hasselbalch equation. The discovery and subsequent study of acids and bases using this equation has led to the discovery of many important phenomena in the natural world from as how cells function to how materials are formed.

However, after years of study, an idea arose that questioned the validity of the Henderson-Hasselbalch equation, what happens at the surface? If you have a beaker filled with a dilute acid, what happens at the very top atomic layer? The top layer of a liquid in a beaker is special for many reasons, but if you’re a dissolved molecule, it means that you’re no longer surrounded by water on all sides. For hydrophobic molecules, this means that it is favourable to be at the surface. With this in mind, the scientists took another look at the Henderson-Hasselbalch equilibrium equation and thought that it couldn’t work at the surface. Many studies have measured indicator chemical species, and determined that the Henderson-Hasselbalch equation does not seem to apply at the surface, and concluded that the concentration of hydronium or hydroxide ions, which determines the acidity/basicity, is different at the air-liquid interface than in the bulk.

>Read more on the MAXIV Laboratory website

 

 

Golden nanoglue completes the wonder material

Modern microelectronics relies on semiconductors and their metal electrodes. High-performance device functionality demands high transistor density within a single chip, which soon will reach the physical limits of bulk materials. Alternatives have been found in atomically thin materials, e.g. graphene and its semiconductive inorganic relatives.

MoS2 (molybdenum disulphide) is the representative inorganic layered crystal with properties similar to those of graphene. To be useful in applications, it must be joined to the metallic electrodes to enable charge flow between the metals and semiconductive (M/S) counterparts. In a recent study, scientists from University of Oulu, Finland have demonstrated the success of joining MoS2 to Ni (nickel) particles by using gold (Au) nanoglue as a buffer material. Through in-house observations and the first-principles calculations, the semiconductor and metal can be bridged either by the crystallized gold nanoparticles, or by the newly formed MoS2-Au-Ni ternary alloy.
A metallic contact is formed, leading to enhanced electron mobility crossing the M/S interface.

>Read more on the MAX IV Laboratory website

Image: representation of gold nanoglue joining molybdenum disulphide and nickel. 

Impressions from the 30th MAX IV user meeting

At the 30th MAX IV user meeting over 250 attendees met to discuss and learn for three days in Lund.

The impressions that we collected from the meeting are positive overall.
There was a very good atmosphere, good backup from the users, lively discussion, and full rooms for the parallel sessions. These are very important signs for for us going forward, says interim director Ian McNulty and science director Marjolein Thunnissen. We also talked to a few of the users who appreciated that the user meeting is a good place to meet with colleagues and collaborators to discuss and learn. The other comment that we got from several of them was that it was important that they now have a clear time plan and overview of the status so that they can plan for their experiments at MAX IV.

>Read more on the MAX IV Laboratory website

First-year operational results of the MAX IV 3 GeV ring

If you fly over MAX IV right now and look down, you’ll see a large circular building. The reason for this size and shape is the 528-meter-long 3GeV storage ring which precisely guides bunches of electrons traveling at velocities approaching the speed of light. As the electrons pass through arrays of magnets called insertion devices, they produce bright X-rays which are then used by beamline scientists to do many different types of experiments.

In an article published this month in the Journal of Synchrotron Radiation, the 3 GeV ring team led by Pedro Tavares describe the results for the first year of operation. This important milestone in the MAX IV project provides validation for many of the brand-new concepts that were implemented in the MAX IV design in order to improve the performance of the machine and reduce downtime.

>Read more on the MAX IV Laboratory website

 

Synchrotrons in Black and White

Recently on social media, a number of synchrotrons have taken part in the Black and White Challenge. The rules are simple, each facility must take a photo every day, in black and white with no people and post it on social media. You are not allowed to explain what is in the photo or why you chose to post it, you must also nominate one more account to take up the challenge every day.

A few weeks ago, MAX IV was nominated by both ESRF and ALBA Synchrotron to take part in the challenge and we accepted. Below are examples from each challenge, along with links to all the photos on Twitter (account not required).

This is a good opportunity to follow our various social media accounts if you haven’t already. We are very active and post exclusive content there that can’t be found anywhere else.

>Read more on the MAX IV Laboratory website

Science Village gets go-ahead to start construction

The detailed development plan for Science Village gets a green light from the Government of Sweden which means that the construction of important support infrastructure for MAX IV and ESS can now start.

“This decision is obviously good for us. We welcome it and we have been waiting for a long time. We are happy for several reasons ­– in general, MAX IV needs neighbors to interact with, so this is an important step in that direction.  The first project for us is the SPACE building that will be constructed for ESS and MAX IV in the near future. In the somewhat more distant future, Lund University plan to move a significant part of their activities to Brunnshög. For that, a green light from the government is mandatory and very much appreciated”, says Christoph Quitmann, Director of MAX IV.

>Read more about the Science Village.

Illustration: ESS