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DOE's Oakland Office to Close by End of 2004, Operations Will Shift To -0 Lam 0 fit U- fc Secretary Abraham Sends a Warm The Green Gets a Needed UPqIrade Thank you for an Enjoyable Visit ByShawna -a- Williams SLAC employees on their way Djrect pI,.e.Sr t r in. to and from the Cafeteria OFF:JCIAL IES^-° le-70 \~~~~~ ,^ may notice construction StanfAor ll ~a e,.. 2 Ad work on The Green over the as'^ -- "" next few months. gt4.u;..? Cli 275WdH rna 9402 The goal is to repair leaks in (Ulu2 L-as the irrigation cn system, "which ro cause a bog-type 0>I 1 1 1 effect," said 8 53 1,* I l tl t 1 | St 1 t ** * t ;" ...... U~~~lliili~~~~l""'"""'" ~~~.............. B * &-Z Liam Robinson, 0JJ facilities support -CJ- for manager Stan Namura (left) and Vicente Garnica look on as Angel ^O=Ke 'ILA-1M 9-%titthntc^Eb~wrAIMu lnt ur cr-Nr-x Site Engineering Martinez digs an irrigationtrench on The Green. All are WASHINGTON, D.C. 20585 and Maintenance employees of SLAC's landscaping contractor. (SEM). replace the one that died and was cut January 7, 2003 "The area may not be usable for the down. The irrigation repairs would next three months, but it will improve make a new tree's survival more the usability for the next 10 or 20 likely, since cork oak thrives in drier years," Robinson said, adding that Dr. Jonathan Dorfan soil. pedestrians should exercise caution Director on The Green in the next few months. For more information on this project, Stanford Linear Accelerator Center contact: Liam Robinson (SEM), Ext. 2575 Sand Hill Road Planners are also exploring the 2980, [email protected] 0 Menlo Park, California 94025 possibility of planting a cork oak to Dear Jonathan: DOE's Oakland Office to Close by Just a short note to thank you for making my visit to End of 2004, Operations Will Shift the Stanford Linear Accelerator Center (SLAC) successful. I appreciated your kind introduction to the to New Service Center packed all-hands meeting that you and your staff put together. Also, your tour through the SLAC was By Neil Calder extremely interesting and informative. The DOE recently announced that they will close the Oakland National I am impressed with the operation of SLAC and its Nuclear Security Administration contribution to fundamental science and to advances (NNSA) Service Center as part of a in technology that have come from that fundamental reorganization. We sat down with science research. John Muhlestein, head of DOE's Stanford Site Office, for more details Again, I appreciate the hard work of you and your on this upcoming change. staff. I look forward to a return visit. What has changed in the Sincerely, Department of Energy's organization n-V in the Bay Area? 0 0' "On December 17, 2002, DOE's 5I >c NNSA, which oversees the Bay ro 1) Area's Lawrence Livermore National Spencer Abraham n Laboratory and Sandia National 0 Laboratories, implemented a new House Science Committee Staff organizational structure, with John Muhlestein, head of DOE's Office Visits SLAC Albuquerque becoming the main of Science Stanford Site Office. Service Center." usual until transition plans have been "This new structure will streamline established and implementation of operations and oversight while links with the new Service Center has clarifying roles and responsibilities. begun. I will make sure that everyone A direct consequence of this at SLAC is kept fully informed of reorganization is that the DOE's developments."@ Oakland Service Center, which provides our Office of Science Stanford Site Office with a wide range of services, will close by the end of 2004." a/) How will these changes affect 0) 0 0: SLAC? co cd ro "SLAC staff should be reassured that there will be no sudden changes. We -0 0 4-(- still expect to get support from the 0 -C CL Oakland Service Center during the two years of transition. Members of the House Science Committee Staff, Gabe Rozsa, Tina Kaarsberg, Charlie Cook and Chris King, toured SSRL as part of their January 13 visit to SLAC. As an We do not yet know which center example of the kind of biological puzzles that can be examined with SSRL's technical will take over responsibility for capabilities, Linda Brinen (SSRL), far right, shows the visitors the molecular structure SLAC support, but it is business as of the anthrax lethal factor. New Gate House to be Built at MFD & Klystron Departments SLAC Main Gate Specialize in Hydrogen Brazing ff 0 0 By Kelley Ranlsey i) 0 A particularly unique technology Ol used in the Mechanical Fabrication 0 I (MFD) and Klystron and Microwave (KLY) departments is ultra-clean, C E:3 high temperature hydrogen furnace -c brazing. Hydrogen brazing is an essential .) C assembly technique for joining u components and assemblies for Ir V) critical ultra high vacuum (UHV) systems such as klystrons and This design sketch shows the nrew Gate House for the SLAC Main Gate. accelerator structures. By Shawna Williams Construction should begin on the In hydrogen brazing, a metallurgical new building in late February, Say goodbye to the old guard shack bond is achieved using a filler-metal around the time the current work at SLAC's Main Gate. It will be torn having a lower melting point than on extending utilities to the new down and replaced in the next few the materials being joined. One of the guest house will be completed. The months. primary benefits of brazing is that building should take two to three the mating surfaces form a complete "The guard house that's there now months to complete. A temporary metallurgical joint. When heated in Derrik Soares (MFD) lifts the furnace has a huge leak problem," explained shack will be set up further down the pure hydrogen atmosphere, the heating elemtent off a red hot retort. Rick Yeager, Manager of Labratory the hill from the current one, and filler-metal melts, wets the surfaces Safeguards/Security. "It's old, it's traffic lanes at the main entrance will to be joined, and is drawn between carbon steel, molybdenum, Glidcop, outdated, there are holes in the probably be narrower. the mating surfaces by capillary Kovar and metallized alumina. The wall-it doesn't look nice." Yeager said hours at the Alpine action. The result is a high quality, filler metal is usually an alloy of The spacious new Main Gate House, Gate might be extended during the permanent metallurgical seal. copper and gold, but other alloys containing silver, nickel, indium, in addition to being more comfortable construction. Check the Web and With other joining techniques such palladium, and other metals are and attractive, will allow for the posted signs for further information as welding or mechanical seals, often used. The brazing process installation of a modern fire alarm on Alpine Gate hours. a unbounded mating surfaces can trap takes place in a specially designed system that relays more information contaminants, are difficult to out- furnace that employs controlled to firefighters. gas and can cause problems with heating cycles in the range between UHV systems. In addition, the high 750 and 1100 degrees Celsius. The temperature pure hydrogen brazing New Signs Promote Safety brazing atmosphere is contained in a atmosphere has powerful cleaning cylindrical retort that can measure 36 effects. Oxides of metals such as 0 inches across and 10 feet in length. Ol copper, nickel, iron and chromium cn ro0w are readily reduced and eliminated, At the present time, this technology is 0pa) resulting in a bright clean surface. being used to assemble components 0: Many other contaminants are required for SSRL and the SPEAR3 0 volatilized and removed during the Upgrade, the Accelerator Department Q..0. n-' brazing process. Modified processes and NLC. We also do special brazing can be employed, such as the use work for other national labs and Alert commuters might have noticed a new yellow warning sign that of wet hydrogen. This method universities. appeared just beyond the Main Gate on January 22. This was one of eight is currently being used for final signs posted at SLAC entrances recently, part of the Lab's For more information on the ongoing effort to processing of high-gradient Next keep safety a priority in all our activities. Mechanical Fabrication Department, Linear Collider (NLC) test structures see: http://www.slac.stanford.edu/ The ES&H Coordinating Council (which encompasses all divisions) decided to reduce surface carbon. grp/mfd/ to post the signs to let visitors and contractors know that they should Many different materials can be be vigilant and inquire as to SLAC For more information on the Klystron safety issues with which they may joined by hydrogen furnace brazing. be unfamiliar. Employees and others in the SLAC community and Microwave Department, see: who have Most brazing at SLAC involves completed the appropriate ES&H training should already be aware of hazards http://wwvw.slac.stanford.edu/grp/ joining copper and/or stainless steel, here. kly/index.html 0 however other materials commonly For more information, contact: Rachel Claus (BSD), Ext. 4343, brazed at SLAC include nickel, iron, [email protected] 0 TYPES OF DETECTORS AND HOW of detectors. Ionizing detectors To avoid nuisance alarms place Smoke Detector THEY WORK respond slightly faster to flaming fires detectors: while photoelectric detectors respond Basics Ionization smoke detectors: *Away from furnace or air faster to smoldering fires. Ideally, a conditioner vents Find Out More About One of The ionization chamber smoke home should be protected by at least · Away from bathrooms to avoid the Most Important Devices detector has a small radiation source one of each.
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