From Director Chi-Chang Kao
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SSRL passed yet another important milestone in July, when the first SPEAR3 fill
for user operations on Wednesday morning, July 25, was a little different than
all the prior user operations fills in the forty year history of SSRL. The
SPEAR3 current display climbed up through 350 mA without stopping as SSRL
delivered the first user operations shifts at 450 mA. This milestone
represented the culmination of over a decade of effort conceptualizing,
designing, fabricating, installing, and commissioning the SPEAR3 storage ring
and associated beam line upgrades, followed by developing and validating the
safety of top off injection and beam line operations at elevated current.
Along the way, SPEAR3's emittance has been reduced from the 18 nm*rad design
emittance to the present 10 nm*rad, new undulators have been deployed, the low
alpha short pulse operations mode has been developed and implemented, and the
beam stability has been enhanced. Performance improvement will not stop with
this latest milestone. Over the past year a number of accelerator physics
shifts have been devoted to reducing the SPEAR3 emittance even further.
Approximately 6 nm*rad has been successfully demonstrated, although further
work is required before such an emittance reduction will be realized during
user operations. Nonetheless, it is clear that even brighter times are ahead
for SSRL and for providing our user community new capabilities.
On a different note, mesoscale science and technology opportunities, with input
from the scientific community through several town-hall meetings, were
summarized and discussed at the recent Basic Energy Sciences Advisory Committee
meeting. The priority research areas that were identified include:
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Mastering Defect Mesostructure and its Evolution
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Regulating Coupled Reactions and Pathway-Dependent Chemical Processes
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Optimizing Transport and Response Properties by Design and Control of
Mesoscale Structure
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Elucidating Non-equilibrium and Many-Body Physics of Electrons
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Harnessing Fluctuations, Dynamics and Degradation for Control of
Metastable Mesoscale Systems
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Directing Assembly of Hierarchical Functional Material
In order to realize these opportunities, new capabilities to synthesize,
characterize and model materials on the mesoscale will be needed. SSRL is
poised to take advantage of these opportunities with our emphasis on the
development of tools for multi-scale, multi-model imaging, time-resolved and
in-situ measurements, as well as the integration of theory, synthesis,
characterization and testing.
To engage the user community in this exciting new research direction, a
workshop that will focus on these opportunities will be held at the upcoming
SSRL/LCLS joint Annual Users' Meeting, October 3-6. In addition, Dr. George
Crabtree from Argonne National Laboratory and University of Illinois at
Chicago, who co-chaired the BESAC Mesoscale Subcommittee, will give one of the
key note talks at the Users' Meeting. I encourage you find time to attend the
meeting.
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Science Highlight
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- SSRL Scientists Confirm Method to Make Platinum a
Better Catalyst
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Schematic representation of Pt subsurface
alloys and corresponding shifts in Pt d-band center. |
The ability to customize and control the activities of scarce, expensive
transition metal catalysts is extremely important for the development of
economical industrial and energy-saving processes. Over the years several
methods have been suggested, especially for processes employing platinum, the
most active metal catalyst in many important reactions.
One promising option is to tune chemical functionality by implementing
a ligand effect – in other words, by changing the atomic nearest neighbor
environment, a conceptually simple way to modify the electronic structure of
platinum to enhance its catalytic activity. However, confirming the effect
experimentally has been difficult; conventional methods have been unable to
disentangle the various constituents of such a catalyst's electronic
structure.
Now scientists at the Stanford Synchrotron Radiation Lightsource have
used the unique capabilities of SSRL Beam Line 13-2 to study the ligand effect
in platinum. They used oxygen-resonant x-ray emission and absorption
spectroscopies to look at Pt(111) with either nickel or cobalt embedded in the
subsurface region. These spectroscopic techniques provided the means to probe
the density of states (DOS) projected on an atomic site in both occupied and
unoccupied electronic states. Because of element specificity, the DOS of
chemisorbed oxygen atoms could be disentangled from the substrate states and
any change in the platinum-oxygen chemical bond probed directly.
The researchers used these element-specific core level spectroscopy
techniques to separately probe the catalyst's metal valence states and the
density of the adsorbate (oxygen) states, and were able to show changes in the
strength of the bonding between platinum and its oxygen and hydrogen
adsorbates. This demonstrated how to modify the electronic configuration of the
adsorbate-metal bond and how the resulting effect can translate to improved
catalytic activity. Read more...
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Features
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SSRL Helps in Discovery of How Fungus Could Aid Mine Cleanups
Harvard-led researchers have discovered that an Ascomycete fungus that is
common in polluted water produces environmentally important minerals during
asexual reproduction.
The key chemical in the process, superoxide, is a byproduct of
fungal growth when the organism produces spores. Once released into the
environment, superoxide reacts with the element manganese (Mn), producing a
highly reactive mineral that aids in the cleanup of toxic metals, degrades
carbon substrates, and controls the bioavailability of nutrients.
The results, which will inform a wide range of future studies
in microbiology, environmental chemistry, developmental biology and geobiology,
were recently published online in the Proceedings of the National Academy
of Sciences (PNAS).
The principal investigator was Colleen Hansel, a faculty
associate at the Harvard School of Engineering and Applied Sciences (SEAS).
Co-authors of the study included SSRL staff scientist Sam Webb.
Visit Harvard SEAS to read the full announcement.
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Using X-ray Imaging to Observe Running Batteries in Real Time
Most electric cars, from the Tesla Model S to the Nissan Leaf, run on
rechargeable lithium-ion batteries - a pricey technology that accounts for more
than half of the vehicle's total cost. One promising alternative is the
lithium-sulfur battery, which can theoretically store five times more energy at
a much lower cost. But lithium-sulfur technology has a major drawback: After a
few dozen cycles of charging and discharging, the battery stops working.
"The cycle life of lithium-sulfur batteries is very short," said Johanna
Nelson, a postdoctoral scholar at SSRL. "Typically, after a few tens of cycles
the battery will die, so it isn't viable for electric vehicles, which require
many thousands of cycles over a 10- or 20-year lifetime."
A typical lithium-sulfur battery consists of two electrodes - a lithium metal
anode and a sulfur-carbon cathode - surrounded by a conductive fluid, or
electrolyte. Several studies have attributed the battery's short cycle life to
chemical reactions that deplete the cathode of sulfur.
But a recent study by Nelson and her colleagues is raising doubts about the
validity of previous experiments. Using high-power x-ray imaging of an actual
working battery, the Stanford-SSRL team discovered that sulfur particles in the
cathode largely remain intact during discharge. Their results, published in the
Journal of the American Chemical Society (JACS), could help
scientists find new ways to develop commercially viable lithium-sulfur batteries for electric
vehicles.
Read more in the Stanford News article summarizing these research results, SSRL's
June 2012 science
highlight on the same topic, and the SLAC Today User Spotlight.
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2012 Structural Molecular Biology Summer School Wrap-up
The 2012 Structural Molecular Biology (SMB) Summer School was held at SSRL from
July 16 to 20. This year the School focused on five main applications of
synchrotron radiation to Structural Biology: Macromolecular Crystallography,
Small Angle X-ray Scattering, X-ray Absorption Spectroscopy, X-ray Fluorescence
Imaging and X-ray Emission Spectroscopy. The five-day Summer School included
invited lectures by experts in the field on the first two days, followed by
hands-on data acquisition and practical training sessions on the Wednesday and
Thursday at Beam Lines 2-1 (X-ray Imaging), 4-2 (Small Angle X-ray Scattering),
7-3 (X-ray Absorption Spectroscopy) and 14-1 (Macromolecular Crystallography).
A half day on Friday was devoted to topics including data analysis, how to
write SSRL beam time proposals and some advanced lectures in each of the topics
by invited experts and on data analysis. Although the lectures were aimed at
the graduate student/beginners level, they were also appropriate for
experienced researchers with expertise in one technique and with an interest in
other techniques to further the scope of their Structural Biology research.
Eighteen participants with varying degrees of experience in Structural Biology,
predominantly at the graduate student level, attended the School. Both the
lecture and practical sessions were enthusiastically received by the
participants, expressing thanks to the tutors for providing a valuable learning
experience for everyone involved.
Co-Chairs for the 2012 SMB Summer School were SSRL Staff Scientists Ritimukta
Sarangi, Clyde Smith and Thomas Weiss, with the hands-on data collection and
analysis sessions facilitated in addition by SSRL Staff Scientists Sam Webb and
Tsu-Chien Weng. Funding for the SMB Summer School program is provided by
NIH-NIGMS and DOE-BER.
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Crystallography Users Learn Remote Data Collection
Ahead of NSLS Shutdown
This year's annual RapiData course at the NSLS included a
remote access data collection workshop organized by the Protein Crystallography
Research Resource (PXRR) and SSRL's Structural Molecular Biology group
(SMB). The intent of the workshop was to present a data-acquisition
option for NSLS crystallography users during the transition period between the
end of NSLS operations and the start of NSLS-II. SSRL staff scientists Graeme
Card and Clyde Smith provided hands-on training to the workshop participants in
the use of remote operations and data collection at SSRL macromolecular
crystallography beam lines. While other synchrotrons will certainly contribute
towards users' needs during the NSLS-II transition, SSRL's
expertise with remote users and the ability to handle new users makes it a
leading choice for this remote-user support initiative. Read
more...
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From the Acting Chief Operating Officer: SLAC is a Busy Place These Days:
How's Your Work Planning and Control?
This is an exciting time to be at SLAC: The Arrillaga Recreation Center and
grounds – built through a generous donation from Stanford alum John
Arrillaga – were just completed and opened following a ribbon-cutting
ceremony on Wednesday, July 18.
Then, on track for completion around April 2013, the
65,000-square-foot Research Support Building (Bldg. 52) along Loop Road will
house the Accelerator Directorate. And now, just breaking ground, the Stanford
Research Computing Facility on PEP Ring Road will provide data-center support
to multiple Stanford users.
Adding to this, SLAC is about to shut down our Stanford
Synchrotron Radiation Lightsource (SSRL), Linac Coherent Light Source (LCLS),
Facility for Advanced Accelerator Experimental Tests (FACET) and linac for two
months of scheduled maintenance and repairs. One critical project during this
shutdown will carefully switch SLAC's power to a backup source in order
to repair the 7.5-mile, 230-kilovolt power line (DOE owned) at Skyline
Boulevard that serves as the lab's main power source.
SLAC will continue
the celebration of its 50th anniversary with
2,000 of our closest friends at main events including a formal anniversary
celebration, and a technical symposium focusing on key research areas that will
lead to the lab's next major scientific discoveries. And shortly after
these events, we anticipate welcoming a new lab director to SLAC!
It's easy to find ourselves distracted at a time with so
much activity. And it's times like these when we should be extra vigilant
about planning our work, being aware of what is going on around us, and
watching out for unusual activities. Read
more...
Events
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Pittsburgh Diffraction Conference @ SLAC, September 30-October
2, 2012
The 70th Annual Pittsburgh Diffraction Conference will be held at SLAC
immediately preceding the 2012 SSRL/LCLS Users' Meeting and Workshops on
October 3-6. The Pittsburgh Diffraction Conference is a three-day event
featuring lecture and poster presentations covering a wide range of subjects of
interest to researchers in chemistry, physics and structural biology. The
conference brings together researchers in all areas of fundamental and applied
diffraction and crystallographic research to present current topics. The
program of the 2012 conference includes nanocrystallography, femtosecond
diffraction methods, hybrid methods for structural biology research, powder
diffraction and exciting macromolecular structures. Student poster abstracts
may be considered for an oral presentation and are eligible for the Chung Soo
Yoo Award. Conference social events include an opening reception on September
30 and a banquet on October 1. Register at the conference
website.
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Instruments of Discovery - Past and Future of Synchrotron Light
Sources. A Symposium to Honor Herman Winick on his 80th Birthday, October 2,
2012
A one-day symposium is being held to honor Herman Winick's many contributions
to synchrotron radiation science. Herman, who is Deputy Director Emeritus of
SSRL, has been a strong proponent of synchrotron radiation since he came to
Stanford in the 1970's to lead the technical design of SSRP (the Stanford
Synchrotron Radiation Project). He is best known for his leadership role in the
development of wiggler and undulator insertion devices as advanced synchrotron
radiation sources but has been involved in a number of significant synchrotron
science-related developments over the years. He has also actively promoted the
development of facilities in many countries, the latest being his efforts in
the initiation of SESAME.
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LCLS/SSRL Users' Meeting & Workshops, October 3-6, 2012
Please join us October 3-6 for our Users' Meeting & Workshops. This
annual event is a valuable opportunity to learn about our latest plans, new
developments and exciting research at LCLS and SSRL. It is also a great time to
interact with other scientists, potential colleagues, and vendors of light
source related products and services. Keynote talks will include:
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George Crabtree, ANL, Opportunities with
Synchrotron Radiation at the Mesoscale (October 4)
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Helmut Dosch, DESY, Future Opportunities with
XFELs (October 5)
This year's workshop topics include the following:
- De-Mystifying the Lightsource Experience
- Opportunities for Nanoscale Spectromicroscopy - Hard and
Soft X-ray Imaging
- Science with High Energy X-rays
- Toward Control: Untangling Ultrafast Mechanism of Lattice
and Electron Dynamics
- Translating Your Science for the Public
- Opportunities with Synchrotron Radiation at the
Mesoscale
- LCLS-II Instrument Workshop
More details can be found at the meeting website.
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Advanced Techniques in Actinide Spectroscopy (ATAS),
November 5-7, 2012
Helmholtz-Zentrum Dresden-Rossendorf,
Germany
The workshop focuses on recent advances in actinide
chemistry from both a spectroscopic and theoretical point of view. It covers
vibrational spectroscopy (IR and Raman), laser-induced spectroscopy
(luminescence and photoacoustic), X-ray absorption spectroscopy (XAS) and
quantum chemical calculations. Improvements of in situ experimental
setups, applications of quantum chemical methods in predictive and
interpretative ways as well as new data processing algorithms are major
topics. Conference website.
Announcements
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Call for Nominations for Spicer and Klein Awards - Due August 1
Please submit your nominations for SSRL's annual Klein and Spicer awards to
Cathy Knotts by
August 1. These awards, as well as talks from the award recipients, will
be presented at the joint SSRL and LCLS Users' Meeting during the Thursday,
October 4 plenary session:
William
E. and Diane M. Spicer Young Investigator Award
Melvin
P. Klein Professional Development Award
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Call for Lytle Award Nominations - Due August 15
Take a few minutes to nominate your colleagues, fellow users or staff for the
Farrel W. Lytle Award. The Lytle Award was established in 1998 by the SSRL
Users' Organization Executive Committee to promote important technical or
scientific accomplishments in synchrotron radiation-based science and to foster
collaboration and efficient use of beam time among users and staff at SSRL.
Submit nominations to recognize outstanding achievements by SSRL users or staff
by August 15 (send email to Cathy Knotts). Nominations will be
reviewed and
the recipient selected by members of the SSRL Users' Organization Executive
Committee. The Lytle Award will be presented at the annual Users' Meeting
awards dinner on October 4, 2012.
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User Research Administration Update
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X-ray/VUV Beam Time Requests Due August 13
Please submit X-ray/VUV beam time requests by August 13 to be considered for
beam time during the first scheduling period next year (Nov. 2012-Feb. 2013).
Macromolecular Crystallography beam time requests are due by September 15.
Request beam time via the user portal.
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X-ray/VUV Proposals Due September 1
New SSRL X-ray/VUV proposals can be submitted three times a year: September 1,
December 1, and June 1. X-ray/VUV Proposals submitted by September 1 will be
peer reviewed, rated and eligible for beam time beginning in February 2013.
The next deadline for submitting new Macromolecular Crystallography proposals
is December 1, 2012.
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Submit End-of-Run Survey via User Portal
Comments about your experience at SSRL are extremely important to us. If you
haven't already done so, please submit an End-of-Run Summary through the
user
portal.
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Inform Us of Publications
SSRL provides technical tools for world-leading science at no charge for
scientists who conduct non-proprietary research, with the understanding that
significant results are to be publicly disseminated. Scientists must
acknowledge use of the facility in presentations and publications and must
inform the facility of all publications, theses, awards, patents and other
forms of recognition resulting from research conducted fully or partially at
SSRL. These metrics of scientific achievements and productivity are extremely
important to the facility and to funding agencies. Please contact us as results
are about to be published so that we can work with you to more broadly
communicate your research. More information can be found on our publications page.
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Marguerite Shuttle Adds Early Service to SLAC from Hoover Tower
For you early birds, Stanford has expanded its Marguerite
service to SLAC, adding a shuttle that departs from Hoover Tower on the main
campus at 7:05 a.m. and arrives at SLAC at 7:27 a.m. The free weekday
SLAC/Stanford shuttle service operates every 20 minutes during the day.
Shuttle schedule
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SSRL Headlines is published electronically monthly to inform SSRL users,
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U.S.
Department of Energy Office of Basic Energy Sciences by Stanford
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DOE
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Questions?
Comments? Contact
Lisa Dunn
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