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Physical Sciences Dean Miguel García-Garibay has been elected a 2019 Fellow of the American Chemical Society

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Photo of Miguel García-Garibay

Miguel García-Garibay, Dean of the UCLA College Division of Physical Sciences.

Miguel García-Garibay, dean of the UCLA Division of Physical Sciences and professor of chemistry and biochemistry, has been elected a 2019 fellow of the American Chemical Society, the ACS announced.

García-Garibay is a pioneer in research on molecular motion in crystals, molecular machines and green chemistry.

He has earned worldwide recognition in the fields of organic photochemistry, solid-state organic chemistry and physical organic chemistry. García-Garibay studies the interaction of light and molecules in crystals. Light can have enough energy to break and make bonds in molecules, and his research team has shown that crystals offer an opportunity to control the outcome of these chemical reactions. He is interested in the basic science of molecules in crystals.

His research has applications for green chemistry that may lead to the production of specialty chemicals that would be very difficult to produce by traditional methods due to their complex structures, as well as applications for molecular electronics and miniaturized devices. His research group has made advances in the field of artificial molecular machines and amphidynamic crystals, a term García-Garibay invented, referring to crystals built with molecules that have a combination of static and mobile components. His research is funded by the National Science Foundation, among other funding sources.

“I can get a precise picture of the molecules in the crystals, the precise arrangement of atoms, with almost no uncertainty,” García-Garibay said. “This provides a large level of control, which enables us to learn the different principles governing molecular functions at the nanoscale.”

He has won many honors for his research, including selection as a fellow of the American Association for the Advancement of Science, as well as numerous honors from the National Science Foundation and the American Chemical Society. He is a member of the California NanoSystems Institute and the Society for Advancement of Chicanos/Hispanics and Native Americans in Science, among other scholarly organizations.

ACS fellows are nominated by their peers and selected for their outstanding accomplishments in scientific research, education and public service. The 2019 fellows will be honored at a ceremony during the ACS national meeting in San Diego on Aug. 26.

This story originally appeared here.

4d graphic rendering of iron-platinum nanoparticle

Atomic motion is captured in 4D for the first time

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4d graphic rendering of iron-platinum nanoparticle

The image shows 4D atomic motion captured in an iron-platinum nanoparticle at three different times.
Credit: Alexander Tokarev

Results of UCLA-led study contradict a long-held classical theory

Everyday transitions from one state of matter to another — such as freezing, melting or evaporation — start with a process called “nucleation,” in which tiny clusters of atoms or molecules (called “nuclei”) begin to coalesce. Nucleation plays a critical role in circumstances as diverse as the formation of clouds and the onset of neurodegenerative disease.

A UCLA-led team has gained a never-before-seen view of nucleation — capturing how the atoms rearrange at 4D atomic resolution (that is, in three dimensions of space and across time). The findings, published in the journal Nature, differ from predictions based on the classical theory of nucleation that has long appeared in textbooks.

“This is truly a groundbreaking experiment — we not only locate and identify individual atoms with high precision, but also monitor their motion in 4D for the first time,” said senior author Jianwei “John” Miao, a UCLA professor of physics and astronomy, who is the deputy director of the STROBE National Science Foundation Science and Technology Center and a member of the California NanoSystems Institute at UCLA.

Research by the team, which includes collaborators from Lawrence Berkeley National Laboratory, University of Colorado at Boulder, University of Buffalo and the University of Nevada, Reno, builds upon a powerful imaging techniquepreviously developed by Miao’s research group. That method, called “atomic electron tomography,” uses a state-of-the-art electron microscope located at Berkeley Lab’s Molecular Foundry, which images a sample using electrons. The sample is rotated, and in much the same way a CAT scan generates a three-dimensional X-ray of the human body, atomic electron tomography creates stunning 3D images of atoms within a material.

Miao and his colleagues examined an iron-platinum alloy formed into nanoparticles so small that it takes more than 10,000 laid side by side to span the width of a human hair. To investigate nucleation, the scientists heated the nanoparticles to 520 degrees Celsius, or 968 degrees Fahrenheit, and took images after 9 minutes, 16 minutes and 26 minutes. At that temperature, the alloy undergoes a transition between two different solid phases.

Although the alloy looks the same to the naked eye in both phases, closer inspection shows that the 3D atomic arrangements are different from one another. After heating, the structure changes from a jumbled chemical state to a more ordered one, with alternating layers of iron and platinum atoms. The change in the alloy can be compared to solving a Rubik’s Cube — the jumbled phase has all the colors randomly mixed, while the ordered phase has all the colors aligned.

In a painstaking process led by co-first authors and UCLA postdoctoral scholars Jihan Zhou and Yongsoo Yang, the team tracked the same 33 nuclei — some as small as 13 atoms — within one nanoparticle.

“People think it’s difficult to find a needle in a haystack,” Miao said. “How difficult would it be to find the same atom in more than a trillion atoms at three different times?”

The results were surprising, as they contradict the classical theory of nucleation. That theory holds that nuclei are perfectly round. In the study, by contrast, nuclei formed irregular shapes. The theory also suggests that nuclei have a sharp boundary. Instead, the researchers observed that each nucleus contained a core of atoms that had changed to the new, ordered phase, but that the arrangement became more and more jumbled closer to the surface of the nucleus.

Classical nucleation theory also states that once a nucleus reaches a specific size, it only grows larger from there. But the process seems to be far more complicated than that: In addition to growing, nuclei in the study shrunk, divided and merged; some dissolved completely.

“Nucleation is basically an unsolved problem in many fields,” said co-author Peter Ercius, a staff scientist at the Molecular Foundry, a nanoscience facility that offers users leading-edge instrumentation and expertise for collaborative research. “Once you can image something, you can start to think about how to control it.”

The findings offer direct evidence that classical nucleation theory does not accurately describe phenomena at the atomic level. The discoveries about nucleation may influence research in a wide range of areas, including physics, chemistry, materials science, environmental science and neuroscience.

“By capturing atomic motion over time, this study opens new avenues for studying a broad range of material, chemical and biological phenomena,” said National Science Foundation program officer Charles Ying, who oversees funding for the STROBE center. “This transformative result required groundbreaking advances in experimentation, data analysis and modeling, an outcome that demanded the broad expertise of the center’s researchers and their collaborators.”

Other authors were Yao Yang, Dennis Kim, Andrew Yuan and Xuezeng Tian, all of UCLA; Colin Ophus and Andreas Schmid of Berkeley Lab; Fan Sun and Hao Zeng of the University at Buffalo in New York; Michael Nathanson and Hendrik Heinz of the University of Colorado at Boulder; and Qi An of the University of Nevada, Reno.

The research was primarily supported by the STROBE National Science Foundation Science and Technology Center, and also supported by the U.S. Department of Energy.

This story originally appeared in the UCLA Newsroom.

Photo of the UCLA team that built two NASA satellites to study space weather

UCLA students launch project that’s out of this world

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Photo of the UCLA team that built two NASA satellites to study space weather

UCLA aims to be one of the few universities to ever complete such a sophisticated space science mission — designed and built by students — from beginning to end.

Five years ago, a group of UCLA undergrads came together with a common goal — to build a small satellite and launch it into space. In the years since, more than 250 students — many of whom are now UCLA graduate students and alumni — have been the mechanical engineers, software developers, thermal and power testers, electronics technicians, mission planners and fabricators of the twin Electron Losses and Fields Investigation CubeSats, known as ELFIN.

Although UCLA has been building space instruments for NASA and other international space missions for more than 40 years, and members of its faculty have been critical contributors to space science, ELFIN is the first satellite mission built, managed and operated entirely at UCLA. And even more impressive, just about all of it has been done by the students.

This week, dozens of ELFINers (a nickname earned by those who’ve worked on the satellites), will drive about 150 miles up the California coast from Los Angeles to Vandenberg Air Force Base near Lompoc, to watch the product of their effort ascend into orbit.

“Just seeing all the hundreds of hours of work, that not just myself but others too, have put into this project, the many sleepless nights, the stressing out that you’re not going to make a deadline — just seeing it go up there … I’m probably going to cry,” said Jessica Artinger, an astrophysics major and geophysics and planetary science minor who will begin her fifth year this fall.

The two micro-satellites, each weighing about eight pounds and roughly the size of a loaf of bread, will help scientists better understand magnetic storms in near-Earth space. These storms are a typical form of “space weather” that is induced by solar activity, including flares and violent solar eruptions. Some solar outbursts can impact Earth, generating large amounts of invisible electromagnetic energy that transforms our local space environment.

“Magnetic storms are not just interesting space phenomena. They can energize electrons to high energies that can damage or even destroy orbiting satellites we depend on for GPS, communications and weather monitoring,” said Margaret Kivelson, UCLA professor emeritus of space physics. “They can also enhance space electrical currents which flow onto Earth, and could damage the power grid. Space weather research is also crucial for space tourism and space exploration.”

Currently, scientists’ ability to accurately model and predict space weather is in its infancy, just like meteorology was at the turn of the last century. ELFIN will make headway toward better understanding these phenomena.

ELFIN will go up as a secondary payload with the ICESat-2 mission at dawn on Saturday, Sept. 15, aboard the trusted Delta II, the final and hopefully 100th consecutive successful launch of this type of rocket. The launch will be streamed live on NASA TV’s YouTube channel, as well as on UCLA social media (follow #uclaELFIN).

Photo of Jessica Artinger

Jessica Artinger

Following the launch, many ELFINers at Vandenberg will come back to the campus command center to eagerly await the first Bruin transmissions from space, which are expected about 10 hours after blast-off. UCLA students will be directly involved in day-to-day mission activities and will have privileged access to ELFIN’s data. They will track and command the satellite via a custom-built antenna atop Knudsen Hall and will download data directly to the mission operations center located in the Earth, planetary and space sciences department. The ELFIN website will have interactive tools so the public can track and listen to the spacecraft as it passes overhead twice a day. The CubeSats are expected to remain in space for two years, after which they will gradually fall out of orbit and burn up in the atmosphere like shooting stars.

In fall 2017, as head of ELFIN’s fabrication team, Artinger led a small team that worked tirelessly in the EPSS prototyping lab using band saws, drill presses and a CNC machine (which is used to carve and smooth metal parts) to meticulously craft tightly toleranced components to meet their completion deadline.

“There was a lot of working things out in your head before machining it, especially for safety reasons,” said Artinger, who gave a final inspection by painstakingly sanding each part and then re-measuring each and every hole, comparing them to the technical drawings for accuracy before sending them upstairs to the mechanical team for assembly. The aerospace-grade tolerance requirement across the 13.5-inch long spacecraft, she said, was two thousandths of an inch — about half the thickness of a standard sheet of paper. The team also had to machine the sensitive energetic particle detector frames to an incredibly precise 1/10,000 of an inch, she said.

Artinger, a transfer student who graduated from Orange Coast College in 2016, plans to become a community college professor and can’t wait to use her ELFIN experience to inspire a new generation of students. She says ELFIN really opened her eyes to the power of mentoring through research and further solidified her commitment to teaching topics related to space science.

“Maybe we can discover something at the community college I’ll be working at using the actual data from the satellite that I helped build,” she said. “That would be really cool.”

Photo of Ethan Tsai

Ethan Tsai

Ethan Tsai learned about ELFIN when he was a UCLA sophomore. Despite having no background in space science, the former physics major started to work on simple tasks and gained the necessary skills to become the project’s attitude determination and control subsystem lead. Now studying for his master’s in electrical engineering, Tsai is ELFIN’s project manager.

“I was pretty honored to be able to work on a mission like this,” he said, adding that he never imagined being involved in a NASA mission as an undergraduate. “It wasn’t until about two years into the project that I started to understand and appreciate the quality of the work we were doing and how it’s going to actually affect not just our mission and the students around us but the scientific community as a whole.”

Tsai said he’s excited about the infrastructure he has helped create to make UCLA a “space campus,” supporting students who will work on future satellite missions.

The project has been supported with funding from the National Science Foundation and NASA, with technical assistance from the Aerospace Corporation among other industry partners and universities.

Diagram of ELFIN components

CubeSats like ELFIN pack instruments into a loaf-of-bread sized satellite.

Those who have witnessed the aurora borealis and australis illuminate the skies, also known as the northern and southern lights, have experienced the beauty and power of space weather, likely without even knowing it.

“The aurora is sort of a TV screen that shows us what happens out in space.” said Vassilis Angelopoulos, a UCLA space physicist who got his doctorate at UCLA and serves as ELFIN’s principal investigator. “Space physicists can tell if something interesting or important is going on in space by looking at the aurora.”

Photo of Vassilis Angelopoulos

Vassilis Angelopoulos

ELFIN aims to observe the complex sequence whereby magnetic storms form waves near Earth, accelerating and forcing electrons to fall into the atmosphere, while a network of all-sky cameras across North America captures the resulting brightening of the auroral lights. The field of space science benefits from multi-satellite missions like ELFIN because of the ever-growing need to know about the dynamic conditions in space.

“Just like with atmospheric weather,” Angelopoulos said, “you need multiple space weather buoys to feed their data into our space weather models and be able to make predictions of conditions in the future.”

CubeSats fill this need because of their compact size, relative affordability ($300,000 compared to several hundred million dollars for a typical research satellite), and how quickly a team can go from prototyping to launch compared to standard-sized satellites. CubeSats uniquely allow students to witness end-to-end satellite mission development, testing and operations all within the span of their undergraduate studies.

For ELFINers, being part of an endeavor of this magnitude is reward enough, but working on this project also has professional and scientific benefits, Angelopoulos said. In addition to the leadership, interpersonal, problem-solving and technical skills they’ve developed, ELFINers are also contributing to the production of knowledge, something that is incredibly valuable to society and to their careers as scientists and engineers.

Photo of Ethan Tsai working on flight model assembly

Ethan Tsai works on the flight model assembly for the CubeSat ELFIN.

“As a researcher it’s important to not just analyze data that others collect, but to be involved in designing your own unique experiments to explore new key science questions. This is how space science started, with experiments on small rockets where students were involved in the nuts and bolts of them, and similarly with CubeSats, this is where the future of space science education is headed now,” Angelopoulos said.

Building on the opportunities that exist here at UCLA, and knowing the impact that experiential learning can have on a student’s academic life, Angelopoulos wanted to find a way to bring CubeSat development into the undergraduate experience.

“CubeSats are ideal because they create an environment where students from all walks of life, from all disciplines, can come together and practice what they’ve learned during their formal education in the context of a realistic environment,” Angelopoulos said. “This is exactly what academia, industry and research organizations around the country need — and they tell us that. This is the kind of experience they want in people who are applying to graduate school or who are applying to work in industrial firms because these are people who think on their feet and innovate.”

The launch of the UCLA-student-built ELFIN satellites

We have liftoff of student-built satellites

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The launch of the UCLA-student-built ELFIN satellites

The launch of the UCLA-student-built ELFIN satellites aboard a Delta II rocket from Vandenberg Air Force Base at 6:02 a.m. on Saturday, Sept. 15.

 

For the dozens of UCLA students, faculty, staff and alumni braving the chilly temperatures near Vandenberg Air Force Base on Saturday morning, the brilliant ray of white that radiated across the predawn horizon was the best goodbye ever.

At 6:02 a.m. a Delta II rocket lifted off from the base in Lompoc, California, carrying ELFIN — twin micro-satellites, each weighing about eight pounds and roughly the size of a loaf of bread — into orbit aboard NASA’s ICESat-2 mission.

Saturday’s launch was the culmination of years of planning, dreaming, fabricating, designing, assembling, testing and programming, virtually all of it done by more than 250 UCLA students, most of whom were undergraduates.

“It’s really been a very emotional moment for a lot of students here,” said Ethan Tsai, UCLA graduate student in electrical engineering and ELFIN’s project manager. Tsai, more than two dozen other current students, alumni and faculty, including Vassilis Angelopoulos, professor of space physics and ELFIN’s principal investigator, watched from the VIP area.

“There’s half of my brain that’s trying to stick with the professional mode … and then part of me is just like I can’t believe this thing is launching and I can’t believe this thing is in space,” Tsai said. “I don’t know that it’s sunk in yet. But it’s really emotional for me.”

Luis Frausto, 34, a 2010 UCLA mechanical engineering graduate, who worked on early prototypes of ELFIN, said he was in “total awe” watching the launch from a public viewing site near Vandenberg Middle School.

Frausto, now a design engineer at TAE Technologies, Inc., was one of more than 200 (a record for the Vandenberg public viewing site, according to a base spokesman) who braved the chilly temperatures, including about 40 UCLA ELFINers and a few of their friends, who counted down to zero as the launch went off, sending the crowd into cheers and applause.

“You can’t compare it to watching it on TV. It was like a feeling inside my chest, like I was out of breath,” said Frausto, who left his home in Irvine at 12:30 a.m. to drive the 200 miles northwest to Lompoc. “I’m here and I’m honored to be around everyone who worked on ELFIN.”

ELFIN, which stands for Electron Losses and Fields Investigation CubeSats, is designed to help scientists better understand magnetic storms in near-Earth space. These storms are a typical form of “space weather” that is induced by solar activity, including flares and violent solar eruptions. Magnetic storms can result in damage or even destruction of orbiting satellites that humans depend on for GPS, communications and weather monitoring. Space weather research is also crucial for space tourism and space exploration.

Another former ELFINer who came out was Mike Lawson, who works at the Jet Propulsion Laboratory in Pasadena on the Mars 2020 mission. Lawson slept only two hours on a couch at UCLA before he left Westwood at midnight for what he described as an “emotional” drive on U.S. 101 that included listening to David Bowie’s “Starman.”

“It’s weird. It’s surreal. It was 10 years gone in like 20 seconds,” said Lawson, who earned his bachelor’s degree and Ph.D. in geology from UCLA. The 37-year-old was one of the original ELFINers 10 years ago who worked on prototypes for what would become the satellites that launched this morning. Work began five years ago on the actual satellites that went into orbit, aboard NASA’s final Delta II rocket mission.

Jessica Artinger, an astrophysics major who will begin her fifth year at UCLA this fall, left at 1 a.m. from Fountain Valley in Orange County to make the trip. Since fall quarter 2017, Artinger has led the fabrication team.

“Watching this,” said Artinger, who prior to the launch had expected to cry but despite the dry eyes was nevertheless moved, “my time here means something.”

Louise Tamondong, who is part of ELFIN’s flight operations team, said she got chills watching the launch, which was easily visible for just a few seconds before the rocket was shrouded in thick clouds. About 10 seconds after the sky lit up, the crowd finally heard the roar of the rocket’s engines.

“It felt so unreal that everything that we worked for is going into space … it only felt real when we saw that bright light and everything going up,” said Tamondong. After liftoff, she headed back to Westwood to listen for the first signal from the orbiting ELFIN through an antenna on the roof of UCLA’s Knudsen Hall. They received a signal around 4:30 p.m., confirming that both probes survived the bumpy ride to orbit. The team will now begin commissioning the spacecraft systems and instruments to prepare for the science operations phase.

As a new Bruin, Sixue Xu wasn’t part of the team that designed, tested and built ELFIN. But the graduate student in space physics will be among those who stand to benefit from ELFIN’s work.

“Now it’s our turn,” Xu said, “to make that data into science.”

Ph.D. student mixes science and entertainment to unleash a ‘wow’ factor

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For UCLA biochemistry Ph.D. student Jeffrey Vinokur, science is better when shared.

To share his favorite subject broadly, Vinokur leads a dual life as complex as some of the enzymes he is studying. When he’s not looking deep into the structural analysis of mevalonate-3-kinase in the quiet of his lab, he’s a nationally known chemist-meets-hip-hop dancer named the Dancing Scientist, running a one-man-show that automatically converts every stage into a classroom for zany science experiments.