2008-2009 Colloquia Schedule

 

Oct 2: MEMRISTORS AND THEIR APPLICATIONS

Dr. Dmitri Strukov, Hewlett-Packard Laboratories

The memristor, the fourth passive circuit element, was predicted theoretically nearly forty years ago, but it was just recently demonstrated that memristance naturally occurs at the nanoscale in the systems where both electron and ion motions are coupled under external bias, e.g., in a thin film nonstochiometric oxides with mobile oxygen vacancies. Such thin film memristive devices are readily integrated in nanowire crossbars and since they exhibit both analog and digital properties they can be used to construct ultra-dense digital memories, Boolean logic circuits, and large scale analog adaptive networks.

In this presentation I will review some recent experimental results as well as theoretical aspects of memristors and their applications. I will provide some historical background and address some controversies related to this new technology.

Dmitri Strukov received a MS in Applied Physics from the Moscow Institute of Physics and Technology and PhD in EE from Stony Brook University. He is broadly interested in the physical implementation of computation, including device physics, circuit design, and high level architecture, with the emphasis on emerging device technologies. He is now working at Hewlett Packard Laboratories, Palo Alto on the theoretical aspects of electron transport and switching phenomena in memristive devices.

http://www.hpl.hp.com/news/2008/apr-jun/memristor.html?jumpid=reg_R1002_USEN

http://news.bbc.co.uk/1/hi/technology/7377063.stm

Dr. Stukov's presentation (PDF, 14 MB)

NOTE, THIS IS A SPECIAL COLLOQUIUM, THURSDAY October 2, 2008, at 2 p.m., Bldg 202 Auditorium by

Dr. George H. Miley, University of Illinois

Studies have described inertial electrostatic confinement (IEC) fusion power concepts using either D-He3 or P-B11 fuels to provide a high-power density fusion propulsion system capable of aggressive deep space missions. This presentation will describe a progression of near-term IEC thrusters, starting with a 1 – 10 kWe electrically driven IEC jet thrust followed by a small 50 – 100 kW IEC fusion thruster module for next-generation large satellites.

The initial electrically powered unit is a novel multi-jet plasma thruster based on spherical IEC technology using electrical input power from a solar panel. Ions are generated and accelerated towards the center of double concentric spherical grids, an electrostatic potential well structure is created in the central region, providing ion trapping, and then several enlarged grid opening extract intense quasi-neutral plasma jets. This design provides high maneuverability for satellite and small space probe operations. It offers a unique capability to cover a wide range of power from few watts to kilowatts while retaining good efficiency. The multiple jets provide rapid changes in thrust direction. Estimates show that the IEC electrical efficiency can match or exceed efficiencies of conventional plasma thrusters, e.g., Hall current thrusters, while offering added advantages such as reduced grid erosion (long lifetime), reduced propellant leakage losses (reduced storage weight), and a very high power-to-weight ratio. The multi-jet capability increases control and enables unique missions such as precision probing studies. The technology also has potential use as a power/propulsion unit for a manned interplanetary spacecraft for Mars or beyond.

Dr. Miley is internationally recognized for his research contributions in various areas of nuclear energy, ranging from fusion science/technology to radiation sources and direct radiation energy conversion. He is a professor of nuclear, plasma, and radiological engineering and electrical/computer engineering and director of the Fusion Studies Laboratory at the University of Illinois, Urbana-Champaign. He also holds nine patents and has authored/co-authored three books and more than 350 journal and meeting publications and reports. His academic degrees include a PhD in Chemical/Nuclear Engineering and an MS in Chemical Engineering, both from the University of Michigan, and a BS in Chemical Engineering from Carnegie Tech. In addition, he serves as a consultant to the Lawrence Livermore, Argonne (Illinois), and Los Alamos National Laboratories and as a member of the Illinois Department of Nuclear Safety Radiation Protection Advisory Council and the Governor's Commission on Science and Technology Fusion Task Force.

http://www.ne.uiuc.edu/faculty/miley.php

Dr. Ab Hashemi, LM/ATC, Lockheed Martin Fellow

One of the most significant drivers of change in the engineering field is the rapid advances in design and performance evaluation of products. Historically, product design and development have been achieved by serially focusing on: accurate presentation of the physical product; or, accurate representation of the physics involved; or, accurate representation of the product’s functional characteristics. This technique consists of a time-consuming and cyclic process involving geometric modeling and a series of analysis, each focusing on a different physical discipline. The performance and cost of the final design depends on how effectively and quickly the designers and analysts can accommodate the requirements imposed by each of these disciplines and their interaction with each other. As computing power has advanced, integrated multidisciplinary technology which relies on a common design and modeling environment has evolved. This is a cost efficient way to substantially reduce design time, provide system optimization, and generate accurate predictions. The next step in his process is virtual design which simultaneously considers the geometrical design, physics of the process and the functional performance of the product. This colloquium presentation provides an overview of the process with emphasis to the aerospace industry.

Dr. Hashemi is a Lockheed Martin Fellow and the Chief Scientist for the Strategic and Missile Defense Systems line of business. He led the thermal sciences group at the ATC for 22 years. He received his PhD in mechanical engineering (thermal sciences) from the University of California at Berkeley. In the heat transfer community, Dr. Hashemi is internationally recognized as a visionary in his field. He is a licensed professional engineer, a fellow of the ASME and author or co-author of more than 60 papers and over 50 reports. His previous positions include deputy head of the Thermal Hydraulics Division at Science Applications International Corporation (SAIC) and research scientist and project leader at Stanford Research Institute (SRI) International. Dr. Hashemi has taught undergraduate and graduate courses in heat transfer, thermodynamics, fluid mechanics and dynamics, mathematics and a variety of engineering subjects.

Dr. Hashemi's presentation (PDF, 4 MB)

Dr. Jennifer Wilcox, Department of Energy Resources Engineering, Stanford University

With the United States generating over half of its electricity from coal combustion, and with more than five-hundred 500 megawatt, coal-fired power plants existing in the U.S. with an average age of 35 years, coal as a significant future energy source is inevitable. With imminent plans for CO₂ regulations, coal gasification in the U.S., China, India, and Australia may play a more prominent role. Due to the high pressure of the fuel gas stream from the gasification process, membrane technology becomes an attractive option for effective CO₂ separation and subsequent H₂ production. Within our lab, inorganic membranes are designed with high H₂ permeabilities. Structural properties and sulfur resistance of these membranes is also investigated. These catalytic materials are computationally designed using density functional theory-based energetics obtained from VASP (Vienna ab initio Simulation Package). In a similar manner, materials are also designed within our group for Fischer-Tropsch (FT) applications. Doping traditional FT materials, such as cobalt and iron with trace metals that enhance carbon binding can lead to effective sulfur-resistant FT catalysts that can withstand the harsh conditions associated with coal-to-liquid processes. In total, our research efforts are aimed at minimizing the environmental effects associated with energy conversion from coal, the most abundant energy resource in the U.S.

Dr. Jennifer Wilcox received a Bachelor’s degree in Mathematics from Wellesley College in 1998 and received a Master’s degree in Physical Chemistry and a Ph.D. in Chemical Engineering from the University of Arizona in 2004. She joined Worcester Polytechnic Institute as an assistant professor in the Department of Chemical Engineering in July 2004 and has recently relocated to the Department of Energy Resources Engineering at Stanford University. She has received the NSF Career award for her work in trace element speciation in combustion flue gases and has received the Army Young Investigator award for her work in hydrogen separation with Pd-based membranes.

Dr. Wilcox's presentation (PDF, 5 MB)

Dr. Paul Worden, Stanford University

Gravity Probe B was launched in 2004 to measure two predictions of General Relativity, Geodetic Precession and Frame Dragging. Preliminary analysis was complicated by several effects related to a single cause, electrostatic patches and resulting torques on the gyroscopes. We have recently made significant progress understanding these effects and removing them from the analysis. This gives us a good expectation of obtaining an accurate measurement of the General Relativity predictions. The insights and methods leading to this progress, and some recent preliminary results, will be described.

Dr. Paul Worden is a graduate of Rice University and obtained his Ph.D. from Stanford University. He has been associated with GP-B since 1969 but most of his time since then has gone to another program, STEP (Satellite test of the Equivalence Principle), which tests the foundation of General Relativity. He returned to GP-B data analysis in 2002, and has contributed to studies of several systematic effects.

http://einstein.stanford.edu/

Dr. Worden's presentation (PDF, 3 MB)

Dr. Mark Zoback, Stanford University

The San Andreas Fault Observatory at Depth (SAFOD) main borehole was drilled through the San Andreas fault at a depth of 3.2 km in central California at a location (near Parkfield) where fault creep and repeating microearthquakes are actively occurring.

SAFOD Phase 3 concluded at the end of the summer of 2007 with recovery of nearly continuous cores from two active fault zones at depth. Both sets of cores reveal zones of profound strain localization and probable weakening. The fault zone cores consist of highly foliated zones of cohesionless, compacted fault gouges with clasts of serpentinite and other wall rocks floating in the gouges. There is no evidence of significantly elevated fluid pressure within the fault zone, as had been widely suspected prior to drilling.

For more information about the project, visit http://www.earthscope.org/observatories/safod.

Dr. Zoback is the Benjamin M. Page Professor of Geophysics at Stanford. His principal research interests are related to the forces that act within Earth's crust and their influence on processes related to plate tectonics, earthquakes, and oil and gas reservoirs. He has authored or co-authored approximately 250 technical papers, holds several patents, and wrote the technical reference book Reservoir Geomechanics, published in 2007 by Cambridge University Press.

Dr. Zoback's presentation (PDF, 11 MB)

Dr. Stuart McHugh, LM/ATC

Many think of Siberia as a place of bitter and unending cold, a place of exile, or both. In fact, it is home to about a third of Russia’s population and occupies about three-quarters of its area. Most of Siberia’s population lives along the route of the Trans-Siberian Railroad, in the south, where the climate averages 5 oF in January and 68 oF in July. Built in the late 19th century, the railroad spans almost 6,000 miles (seven time zones) from Moscow to Vladivostok.

Central Asia is the location of the various “stans”—including Kyrgyzstan, Kazakhstan, and Uzbekistan—and the Silk Road, actually many silk routes spanning several thousand miles and linking Asia to the Mediterranean.

This presentation is based on two tours sponsored by the Stanford Alumni Association: a tour in 2007 of the Silk Road and a tour in 2008 along the Trans-Siberian Railroad, which also included the total solar eclipse in Novosibirsk on Aug. 1.

A materials scientist, Dr. McHugh has worked at the Advanced Technology Center for more than 25 years. He received his MS and PhD degrees in Geophysics and an MS in Materials Science, all from Stanford University, and BS degrees in geological engineering and geophysics from the University of Nevada at Reno. One of his hobbies is taking his vacations in out-of-the-way places.

Central Asia (PDF, 9 MB)   Siberia (PDF, 14 MB)   Solar Eclipse Video (WMV, 18 MB)

Dr. Jennifer Saltzman, Stanford University

The Stanford School of Earth Sciences recognizes the need and takes seriously its responsibility to share our understanding of the Earth with the greater community. Consequently, we offer programs for K-12 students, their teachers, and the general public. We aim to bring a basic knowledge of Earth sciences to as many people as possible. From GeoKids, in which first-graders get to know rocks, minerals, fossils, and soils through hands-on activities, to our public lectures aimed at interested, non-expert citizens who wish to be better informed about issues of current importance, we hope to engage everyone in the Earth sciences. For teachers, professional development workshops to supplement science curriculum and strengthen teacher confidence when presenting scientific material.

Jennifer Saltzman has been the educational outreach coordinator at the Stanford University School of Earth Sciences since 2005. Previously, she coordinated education programs at the Farallones Marine Sanctuary Association, the Museum of Science and Industry in Chicago, and the Adler Planetarium. Jennifer taught oceanography at the U.S. Naval Academy, Millersville University, and Harold Washington College. She earned a B.S. at the University of Michigan and a Ph.D. at the University of Rhode Island’ Graduate School of Oceanography.

http://news-service.stanford.edu/news/2007/january17/geokids-011707.html

Dr. Saltzman's presentation (PDF, 6 MB)

Mr. Adam Coates, Stanford University

While helicopters present numerous challenges for control design, human remote control pilots are nonetheless capable of performing extreme aerobatics by learning from experience and from other pilots.

This presentation will cover learning algorithms developed from demonstrations of expert pilots and their flight experiences. These algorithms have been implemented on the Stanford Autonomous Helicopter, which can fly aerobatics at the level of an expert human pilot—well beyond the performance of any other autonomous helicopter

For more information about the autonomous helicopter project, visit http://heli.stanford.edu.

Mr. Coates is an instrument-rated private pilot and a PhD student in Computer Science at Stanford University, working with Professor Andrew Ng. His research focuses on robotics, machine learning, and control. He has co-authored several technical papers on autonomous helicopter flight. Mr. Coates received his MS and BS in Computer Science from Stanford.

http://www.cs.stanford.edu/people/ang/

Mr. Coates' presentation (PDF, 1 MB) (For videos, see http://heli.stanford.edu.)

Mr. Greg Edwards, Lockheed Martin

What is happening with the Internet in regard to computer security today? Over the past few years, there have been fewer virus outbreaks, but viruses, worms and trojans have become more dangerous. Phishing and various variations have increased dramatically. Identity theft has reached epidemic proportions with no end in site.

There are technical solutions to many of these technical problems. However, the “bad guys” are using more social engineering in their attacks and these often defeat the technical controls. Probably the best preventive control is more education on how con artists and fraudsters trick their victims.

This talk will include a review of current problems and suggestions on how to improve security while using the Internet at home and work. Useful URLs also will be provided.

Mr. Edwards works full time in computer security and teaches computer/network/wireless security part time at the University of California Santa Cruz Extension and elsewhere. He has a BS in physics from the University of California at Davis. He also is a Certified Information Systems Security Professional (CISSP), Certified Information System Auditor (CISA), Certified Information Security Manager (CISM), Certified Ethical Hacker (CEH), Certified Wireless Security Professional (CWSP) and Certified Wireless Network Administrator (CWNA). In addition, he has Global Information Assurance Certification in Incident Handling (GCIH) and certification in InfoSec Assessment Methodology (IAM).

Mr. Edward's presentation (PowerPoint, 450 kB)

Dr. Robert Smith, Lockheed Martin

Complementary metal oxide semiconductor (CMOS) techniques allow fabrication of low-cost, high-volume, and high-performance nanotechnology devices that utilize the unique properties of nanomaterials. These devices improve current functions and enable new applications. This presentation will address the challenges associated with the research, development, and productization of carbon nanotube devices; solutions to these issues; and specific applications in microelectronics, communications, power sources, and sensors. For example, nanotube-based/nonvolatile random access memory (NRAM), a new memory storage technology, blends together tiny carbon nanotubes with conventional semiconductors. Dr. Smith, now the director of Lockheed Martin Nanosystems, has spent his career developing, deploying, and supporting technology products for the U.S. government. He has held positions in the public and private sectors and has supported diverse missions and agencies. Dr. Smith holds a BSE in Chemical Engineering from the University of Maryland, a PhD in Chemical Engineering from Auburn University, and an MBA from Johns Hopkins University.

Dr. Smith's presentation

Ingrid Cotoros, Lockheed Martin/ATC

Semiconductors displaying carrier-mediated ferromagnetic order are ideal for both robust information storage and non-thermal, potentially fast spin manipulation and read-out. Prominent examples of such materials are Mn-doped III-V semiconductors, which offer unusual functionalities far beyond conventional ferromagnetic metals or non-magnetic semiconductors.

Custom-designed III-Mn-V heterostructures exhibit rich spin memory effects, and their magnetic properties show strong responses to external stimuli (light, electrical gate, and current) via carrier density tuning. Until now, all demonstrated detection schemes have been static measurements, offering read-out times much slower than the technologically important sub-nanosecond regime.

This presentation will include an ultrafast optical detection scheme for memory read-out functionality and new results of ultrafast photo-induced enhancement of the ferromagnetic order in GaMnAs and the paramagnetic-to-ferromagnetic phase transition around the critical Curie temperature TC.

Dr. Cotoros is a pioneering lead in wireless and infrared thermal detection technology and the principal investigator for a nanotechnology application research and development project at the Advanced Technology Center. She received her BS in Physics from California Institute of Technology and her PhD in Physics at the University of California at Berkeley, where she studied the ultrafast manipulation of strongly correlated materials via photoexcited transient carriers.

Dr. Cotoros' presentation (PowerPoint, 4 MB)

Feb 26: CONTROLLING LIGHT IN PHOTONIC DEVICES USING METAMATERIALS

Dr. David Crouse, City College of New York

Recent discoveries in a new class of metal/dielectric composites called metamaterials or plasmonic crystals include anomalous transmission of light, light channeling, focusing, and super beaming.

Dr. Crouse will discuss both the technology and commercial potential of metamaterials for the development of high-performance sensors, solar cells, ultra-capacitors, and cloaking materials. He also will describe specific applications to the development of tandem solar cells, polarimetric focal plane arrays, and cloaking materials as well as new phenomena of light circulation and weaving in these materials.

Dr. Crouse is an associate professor in the Department of Electrical Engineering at the City College of New York and director of the Center for Advanced Technology in Photonics Applications at the City University of New York (http://www.cunyphotonics.com/). He also founded Phoebus Optoelectronics, LLC, to develop and commercialize nano-engineered materials and devices. His research interests include plasmonic crystals, metamaterials, and nanotechnology. Dr. Crouse received a BS in Physics from Purdue University and a Ph.D. in Electrical Engineering from Cornell University.

Dr. Crouse's presentation

Dr. Andrew Ng, Stanford University

Since its birth in 1956, the artificial intelligence (AI) dream has been to build systems that exhibit broad-spectrum competence and intelligence. The STanford Artificial Intelligence Robot project (STAIR) revisits this dream and seeks to integrate onto a single robot platform tools drawn from all areas of AI including learning, vision, navigation, manipulation, planning, and speech/natural language processing. This is in distinct contrast to, and also represents an attempt to reverse, the 30-year-old trend of working on fragmented AI subfields. STAIR’s long-term goal is to build a useful home assistant robot that can perform tasks such as tidying up a room, using a dishwasher, fetching and delivering items, and preparing meals. For details, visit http://stair.stanford.edu. This presentation will include satellite projects that led to key STAIR components such as (1) robotic grasping of previously unknown objects, (2) depth perception from a single still image, and (3) multi-modal robotic perception; the team’s progress in having the robot fetch items from around the office and take inventory of these items; and some of the main technical ideas that played key roles in enabling these STAIR components. Dr. Ng is an assistant professor of computer science at Stanford University. His research interests include machine learning, reinforcement learning/control, and broad-competence AI. He earned his BSc at Carnegie Mellon, MSc at Massachusetts Institute of Technology, and PhD at the University of California at Berkeley. He also received the Alfred P. Sloan Fellowship and the IJCAI 2009 Computers and Thought Award.

Apr 16: THE QUAKE-CATCHER NETWORK & EARTHQUAKE SENSITIVE COMPUTERS

Dr. Jesse Lawrence, Stanford University

The Quake-Catcher Network (QCN) is a collaborative initiative for developing the world's largest, low-cost strong-motion seismic network by utilizing sensors in and attached to internet-connected computers. With community involvement, the Quake-Catcher Network can provide better understanding of earthquakes and will eventually give early warning to schools, emergency response systems, and others. In the near future thousands of QCN’s low-cost sensors will complement more traditional seismic networks. These sensors will provide unprecedented images of large earthquake ruptures that will show us how earthquakes work. QCN will also benefit engineering by measuring how buildings shake, rattle, and roll. The QCN also provides educational software designed to help teach about earthquakes and earthquake hazards.

Come learn how you can participate in this growing network! For more information, visit the Quake-Catcher Network Web site at http://qcn.stanford.edu/.

Dr. Lawrence is an assistant professor in the Department of Geophysics at Stanford University. He has a BA in Economics from UC Davis and a PhD in Earth Sciences from Washington University in St. Louis. His research interests include deep-earth imaging (like sonograms for the Earth), computational algorithm development, earthquake ruptures, and distributed data acquisition.

http://www.economist.com/science/displaystory.cfm?story_id=12295198

Dr. Lawrence's presentation

Apr 23: WHAT COULD SMART(ER) ENERGY SOLUTIONS LOOK LIKE FOR THE U. S.?  AND WHAT IS NEEDED TO GET THERE?

Dr. Margot Gerritsen, Stanford University, Department of Energy Resources Engineering

Solutions for developing a more energy- efficient, more sustainable, and less energy-dependent society are not straightforward.

Dr. Gerritsen will discuss the energy solutions put forward by the new administration, particularly those in the stimulus package. In addition, she will address not only renewable energy solutions, but also fossil fuels, including peak oil and clean coal. For more information, visit http://margot.stanford.edu.

A faculty member in the Department of Energy Resources Engineering at Stanford University, Dr. Gerritsen specializes in developing computational models for flow in gas and oil reservoirs and tidal energy systems, teaches courses in computational modeling and energy systems, and pursues an interest in energy portfolio analysis. She has an MSc in applied mathematics from the Delft University of Technology in the Netherlands and a PhD in scientific computing and computational mathematics from Stanford University.

Dr. Gerritsen's presentation

Apr 30: LEAD-FREE SOLDERS FOR ELECTRONICS APPLICATIONS

Dr. Gregory Henshall, Hewlett-Packard Co.

International legislation restricting the use of hazardous materials has driven the electronics industry to transition away from traditional tin-lead solders to new, lead-free alloys. These materials have been used successfully in the consumer electronics sector for almost three years, yet challenges remain for their reliable implementation in applications demanding higher reliability and longer life.

This presentation will describe drivers for the use of lead-free electronics in such applications, the risks that must be addressed in their implementation, and how to manage those risks.

For more information, visit http://www.hp.com/hpinfo/globalcitizenship/index.html.

Dr. Henshall is an engineer at Hewlett-Packard, where he has focused on electronic interconnect reliability, including electronics manufacturing and materials issues related to the lead-free transition. He received a bachelor’s degree in physical metallurgy from Washington State University and his PhD in materials science from Stanford University. He formerly was a staff scientist at Lawrence Livermore National Laboratory. Dr. Henshall is involved with several industry partnerships and consortia. He also represents HP on the JEDEC JC14 Quality & Reliability committee and chairs iNEMI’s Pb-Free Alloy Alternatives project.

Dr. Henshall's presentation (PDF, 2 MB)

May 7: NANOTECHNOLOGY IS ALREADY PERVASIVE

Dr. Ricardo Zednik & Dr. Z. Pan, Exponent Failure Analysis Associates

Nanotechnology has been touching our daily lives for decades, even centuries. Focusing on advanced ceramics, this presentation will place current nanotechnology research in a historical context. For example, perovskite ceramic capacitors are by far the most common electronic part in digital electronics today and are routinely manufactured at the nanoscale.

Nevertheless, these ceramic materials are not very well understood at the nanoscale, and significant questions remain unanswered. Recent advances have drawn extensive attention to the remarkable size-dependency of material properties and unexpected phenomena related to downscaling. Given the ubiquitous nature of this class of materials, an improved understanding is critical for further advances in nanotechnology.

Doctors Zednik and Pan are associates at Exponent Failure Analysis Associates, an engineering and scientific consulting firm. Their expertise includes ceramics, electronic materials, thin-films, and microfabrication. Dr. Zednik received a BS in materials science and engineering and a BA in economics from Rice University in Texas and an MS and a PhD in materials science and engineering from Stanford University. Dr. Pan has a BS and an MS from Tsinghua University in Beijing and a PhD from Northwestern University in Illinois, all in materials science and engineering.

http://www.exponent.com/ricardo_zednik/

http://www.exponent.com/zixiao_pan/

May 21: UPDATE ON THE SPACE ELEVATOR

Mr. Ben Shelef, The Spaceward Foundation

The Space Elevator is probably the most daring space access proposal on the drawing boards today, offering mankind a way to expand its habitat beyond the confines of the Earth and enable a true spacefaring civilization. This presentation by the Spaceward Foundation is a light-technical talks that covers the history, basic concept, and future prospects of the Space Elevator.

The presentation is given by Ben Shelef, a co-founder of the Spaceward Foundation and a member of the Space Elevator community. An aerospace engineer by day, he dons the cape and mask of Space Elevator crusader by night, and engages in daring escapades such as running the $4,000,000 Space Elevator challenge, developing Carbon Nanotube technology, and giving talks like this one.

For more information, see http://www.spaceward.org.

Mr. Shelef's presentation (PPT, 3.5 MB)

May 28: ALIGNED CARBON NANOTUBES FOR NANOSTRUCTURED LITHIUM-ION BATTERY ELECTRODES

Dr. Daniel T. Welna, AFRL/RXBN

Nanostructured electrodes offer an exciting solution to current battery technology limitations related to their size and power-to-weight ratio. Although nanostructured electrodes can lead to significantly increased performance, there is a need to understand how nanoscale morphology affects electrochemical behavior.

This presentation will focus on the relationship between electrochemical behavior (capacity, cyclability, and rate capability) and nanoscale morphological control of lithium-ion battery electrode materials, specifically analysis of carbon-based electrode materials. An examination of vertically aligned multi-walled carbon nanotube electrodes has shown significant improvement in both the lithium-ion storage capacity and the rate capability compared to other carbon-based electrodes and other negative electrode materials.

Dr. Welna works as an on-site research scientist for Universal Technology Corporation at the Air Force Research Laboratory (AFRL). He obtained his PhD in chemistry from Pennsylvania State University, studying the synthesis of electrolyte materials for energy storage applications. Following his graduate work, he became a National Research Council post-doctoral research associate at AFRL, where he focused on the development and evaluation of electrode materials for lithium-ion batteries. He has a BA in chemistry from Saint John’s University in Minnesota.

Dr. Welna's presentation (PDF, 5.6 MB)

June 4: MAGNETIC RECONNECTION IN GEOSPACE

Dr. Karlheinz Trattner, Lockheed Martin/ATC

Magnetic reconnection is a fundamental process in magnetized plasma where magnetic field lines are broken and reconnected, converting inflowing magnetic energy into heat and bulk kinetic energy. Reconnection is responsible for many dynamic processes just above the sun’s surface, in planetary magnetospheres, and around other astrophysical bodies.

Science satellites employing particle instruments and imagers, together with ground-based observations from all-sky cameras and radar arrays, are used to study the consequences of magnetic reconnection in the magnetosphere. Of special interest are the cusp regions where all magnetic field lines at the outer boundary of the magnetosphere (magnetopause) converge in a relatively confined space. A signature of every process that occurs at the magnetopause can be found in the precipitating magnetosheath ions in the cusps. This presentation will cover various methods developed for particle and radar observations and emissions from imagers that are used to gain insights into details of the reconnection process, including the continuity, pulsation frequency, and location of the reconnection site.

Dr. Trattner is a group leader at the Lockheed Martin Space Science Laboratory. He is involved in the Interstellar Boundary Explorer (IBEX) and Magnetospheric Multi Scale (MMS) programs and participates in several NASA and European Space Agency (ESA) geospace missions. After receiving his PhD in geophysics from Karl Franzens University in Graz, Austria, in cooperation with the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, he worked on cosmic rays and the cusp regions at ESA and the University College London.

Dr. Trattner's presentation (PDF, 6 MB)

June 11: WATER, THE STRANGEST LIQUID

Dr. Anders Nilsson, SLAC National Accelerator Laboratory/Stanford Synchrotron Radiation Lightsource

Many important physical, chemical, biological, and geological processes involve water – the key compound for our existence on this planet. Although water is the most common molecular substance, it is also the most unusual with many anomalies, such as compressibility, density variation, and heat capacity, in its thermodynamic properties.

The structure of the hydrogen bonding network in water has been discussed for more than 100 years but has not yet been resolved. This presentation will describe recent x ray spectroscopy and scattering measurements showing that water is an inhomogeneous liquid with a dynamical equilibrium between two types of local structures driven by incommensurate requirements for minimizing enthalpy and maximizing entropy.

Dr. Nilsson is a professor in photon science at the Stanford Synchrotron Radiation Lightsource, which is part of the Stanford Linear Accelerator Center (SLAC) National Accelerator Laboratory, and is deputy director of the Stanford Institute of Materials and Energy Sciences at SLAC. He has an MS in chemical engineering from the Royal Institute of Technology in Stockholm and a PhD in physics from Uppsala University, both in Sweden. For more information, visit http://www-ssrl.slac.stanford.edu/nilssongroup/ or http://www.slac.stanford.edu/.

Dr. Nilsson's presentation (PDF, 4 MB)

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