This subproject is one of many research subprojects utilizing theresources provided by a Center grant funded by NIH/NCRR. The subproject andinvestigator (PI) may have received primary funding from another NIH source,and thus could be represented in other CRISP entries. The institution listed isfor the Center, which is not necessarily the institution for the investigator.In FT-ESR and DQC ESR we use microwave pulses with a width of a few nanoseconds. The generation of such pulses requires the use of very fast microwave switches. We purchased from several vendors the fastest switches available on the market. They are based on different types of fast pin-diodes. We found their switching speed is limited to 1-1.5 ns for the rise time and to a somewhat greater value of 1.5-3.5 ns fall times. Also, jitter is observed on the shorter edges. We need faster, more stable switching with both rise and fall times shorter than 1 ns and negligible video transients. Also, it is difficult to bring two short pulses close to each other using pin-diode switches. We successfully tested a switch based on MMIC technology, with improved performance characteristics, and switching in both directions in 1 ns at optimal conditions. This type of switch requires a very fast driver capable of generating voltage swings of 6 V in less than 1 ns and a 300 MHz data rate. This is challenging but we are close to a solution of this problem. In order to minimize the switching time and reduce the jitter to an insignificant level the switch needs to be integrated with the driver using surface-mount technology and wire-bonding techniques. Further progress on this pending project is contingent on the availability of funds needed to connectorize switches based on MMICS FET switches available in chip form. The connectorized package is required to make the switch suitable for practical use throughout the 6-18 GHz frequency range.

Agency
National Institute of Health (NIH)
Institute
National Center for Research Resources (NCRR)
Type
Biotechnology Resource Grants (P41)
Project #
5P41RR016292-07
Application #
7602616
Study Section
Special Emphasis Panel (ZRG1-BCMB-K (40))
Project Start
2007-09-01
Project End
2008-08-31
Budget Start
2007-09-01
Budget End
2008-08-31
Support Year
7
Fiscal Year
2007
Total Cost
$5,766
Indirect Cost
Name
Cornell University
Department
Chemistry
Type
Schools of Arts and Sciences
DUNS #
872612445
City
Ithaca
State
NY
Country
United States
Zip Code
14850
Jain, Rinku; Vanamee, Eva S; Dzikovski, Boris G et al. (2014) An iron-sulfur cluster in the polymerase domain of yeast DNA polymerase ?. J Mol Biol 426:301-8
Pratt, Ashley J; Shin, David S; Merz, Gregory E et al. (2014) Aggregation propensities of superoxide dismutase G93 hotspot mutants mirror ALS clinical phenotypes. Proc Natl Acad Sci U S A 111:E4568-76
Georgieva, Elka R; Borbat, Peter P; Ginter, Christopher et al. (2013) Conformational ensemble of the sodium-coupled aspartate transporter. Nat Struct Mol Biol 20:215-21
Airola, Michael V; Sukomon, Nattakan; Samanta, Dipanjan et al. (2013) HAMP domain conformers that propagate opposite signals in bacterial chemoreceptors. PLoS Biol 11:e1001479
Airola, Michael V; Huh, Doowon; Sukomon, Nattakan et al. (2013) Architecture of the soluble receptor Aer2 indicates an in-line mechanism for PAS and HAMP domain signaling. J Mol Biol 425:886-901
Sun, Yan; Zhang, Ziwei; Grigoryants, Vladimir M et al. (2012) The internal dynamics of mini c TAR DNA probed by electron paramagnetic resonance of nitroxide spin-labels at the lower stem, the loop, and the bulge. Biochemistry 51:8530-41
Smith, Andrew K; Freed, Jack H (2012) Dynamics and ordering of lipid spin-labels along the coexistence curve of two membrane phases: an ESR study. Chem Phys Lipids 165:348-61
Yu, Renyuan Pony; Darmon, Jonathan M; Hoyt, Jordan M et al. (2012) High-Activity Iron Catalysts for the Hydrogenation of Hindered, Unfunctionalized Alkenes. ACS Catal 2:1760-1764
Gaffney, Betty J; Bradshaw, Miles D; Frausto, Stephen D et al. (2012) Locating a lipid at the portal to the lipoxygenase active site. Biophys J 103:2134-44
Dzikovski, Boris; Tipikin, Dmitriy; Freed, Jack (2012) Conformational distributions and hydrogen bonding in gel and frozen lipid bilayers: a high frequency spin-label ESR study. J Phys Chem B 116:6694-706

Showing the most recent 10 out of 72 publications