RSI Nameplate
  • Volume/Page
  • Keyword
  • DOI
  • Citation
  • Advanced
   
 
 
 

Flickr Twitter iResearch App Facebook

BROWSE VOLUMES

Year Range: 
Search Issue | RSS Feeds RSS
Previous Issue Next Issue

Mar 2012

Volume 83, Issue 3, Articles (03xxxx)

Issue Cover Spotlight Figure

Rev. Sci. Instrum. 83, 031301 (2012); http://dx.doi.org/10.1063/1.3688856 (11 pages)

Ronald P. Manginell, Matthew W. Moorman, Jerome A. Rejent, Paul T. Vianco, Mark J. Grazier, Brian D. Wroblewski, Curtis D. Mowry, and Komandoor E. Achyuthan

Microsamplers with low-power, low-outgassing, hermetic microvalves are poised for field sampling of light gases in applications including altitude-resolved collection of gases relevant to climate and weather.   The microsamplers are shown on a mirror, reflecting the weather on a spring day in Albuquerque, New Mexico. (Photo: Randy Montoya, Sandia Laboratories.)

Enlarge Image | Read More
Return to All Sections
back to top
RSS Feeds
back to top Electronics; Electromagnetic Technology; Microwaves

Accurate and low jitter time-interval generators based on phase shifting method

P. Kwiatkowski, Z. Jachna, K. Różyc, and J. Kalisz

Rev. Sci. Instrum. 83, 034701 (2012); http://dx.doi.org/10.1063/1.3690383 (4 pages)

Online Publication Date: 1 March 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
The paper describes two time-interval generators based on the phase shifting method. The first one utilizes the digital clock manager units integrated in a field programmable gate array (FPGA) device and has jitter below 65 ps (rms) over the range of 4 ns–50 ms, while the second one utilizes a separate direct digital synthesizer and has jitter below 15 ps (rms) over the range of 10.2 ns–50 ms. The phase shifting method can be used to design new low-cost and high-precision time-interval generators using the popular FPGA technology.
Show PACS
84.30.Ng Oscillators, pulse generators, and function generators
84.30.Sk Pulse and digital circuits

Design and testing of multi-standard waveguide couplers

S. Beeson and A. Neuber

Rev. Sci. Instrum. 83, 034702 (2012); http://dx.doi.org/10.1063/1.3692739 (4 pages)

Online Publication Date: 15 March 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
Most applications that use waveguides are designed for a single frequency or single band of frequency, and thus the waveguide dimensions are chosen for single mode operation. In special cases where multiple frequencies across multiple bands are needed (i.e., probing the temporal response of decaying plasma using a cw source that is generated by a pulsed source), special techniques must be used in order to implement both sources into a single waveguide structure. This paper presents two types of couplers designed to implement x-band frequencies into an s-band system with a large coupling coefficient (< −10 dB) and small reflection coefficient (> −10 dB) at the design frequency of 11 GHz. Along with a discussion on the design procedure, a detailed description on the parameter optimization and initial values estimation is presented. The custom waveguide structures were tested utilizing an Agilent E8364B PNA network analyzer, and showed reasonable agreement with the simulated performance over the frequency range of interest.
Show PACS
84.40.Az Waveguides, transmission lines, striplines
07.68.+m Photography, photographic instruments; xerography

Development of a compact cylindrical reaction cavity for a microwave dielectric heating system

Myungsik Kim and Kwangsoo Kim

Rev. Sci. Instrum. 83, 034703 (2012); http://dx.doi.org/10.1063/1.3693344 (6 pages)

Online Publication Date: 16 March 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
This paper describes a compact reaction cavity for a microwave-assisted synthesis system. The microwave dielectric heating is a key technology to improve synthesizing yield, however, the large size of the microwave generation and reaction parts in an all-in-one system is a major obstacle when applying the technique to various systems, of which the installation space is limited. For this particular problem, a compact stand-alone cylindrical reaction cavity was developed in the current study. A microwave excited from a monopole probe, which is inserted into the side of the cavity, is transferred to a reaction mixture through the upper hole of the cavity. The cavity is miniaturized by filling it with an alumina ceramic dielectric. Fine-tuning of the resonance frequency becomes available by controlling the length of the inserted screw between the probe and the upper hole. The physical properties of the cavity were simulated using high frequency structural simulator (HFSS) and the produced cavity was tested using an Agilent E8357A network analyzer. The test results show that the developed cavity is able to send enough energy to various solvents.
Show PACS
84.40.-x Radiowave and microwave (including millimeter wave) technology
07.20.Hy Furnaces; heaters
Author Select

Low temperature laser scanning microscopy of a superconducting radio-frequency cavity

G. Ciovati, Steven M. Anlage, C. Baldwin, G. Cheng, R. Flood, K. Jordan, P. Kneisel, M. Morrone, G. Nemes, L. Turlington, H. Wang, K. Wilson, and S. Zhang

Rev. Sci. Instrum. 83, 034704 (2012); http://dx.doi.org/10.1063/1.3694570 (12 pages) | Cited 3 times

Online Publication Date: 16 March 2012

Full Text: Read Online (HTML) | Download PDF

Show Abstract
An apparatus was developed to obtain, for the first time, 2D maps of the surface resistance of the inner surface of an operating superconducting radio-frequency niobium cavity by a low-temperature laser scanning microscopy technique. This allows identifying non-uniformities of the surface resistance with a spatial resolution of about 2.4 mm and surface resistance resolution of ∼1 μΩ at 3.3 GHz. A signal-to-noise ratio of about 10 dB was obtained with 240 mW laser power and 1 Hz modulation frequency. The various components of the apparatus, the experimental procedure and results are discussed in detail in this contribution.
Show PACS
85.25.-j Superconducting devices
42.62.Eh Metrological applications; optical frequency synthesizers for precision spectroscopy
Return to All Sections
Close

Google Calendar

ADVERTISEMENT

Go to AIP Home   © AIP Publishing LLC
close