Resonant scanner

T. N. Rudakov, J. H. Flexman, V. T. Mikhaltsevitch, P. A. Hayes, W. P. Chisholm, C. N. Aitken, and J. H. Feldman, Nuclear Quadrupole Resonance Scanner for Detecting Explosives in Mail, Has Low Equivalent Series Resistance Switch to Switch Capacitance of Tunable circuit Enclosed by Electromagnetic Shield, US Patent Application No. US2006012366-A1 (2006). 

Leica TCS SP5 Resonant Scanner Confocal or equivalent fast imaging fluorescent microscope. 

Table 9.2. Overview of a possible scan protocol applied to a whole-body magnetic resonance scanner with 32-receiver channels. Total scan time approximately 55 min...

Session Time that a single sulgect is in the magnetic resonance scanner can be two hours for IMRI. 

In 1977, Raymond Damadian and colleagues built their first magnetic resonance scanner and named it Indomitable. It is housed in the Smithsonian. 

II. Nuclear Magnetic Resonance Scanners as Medical Instruments... 

II. NUCLEAR MAGNETIC RESONANCE SCANNERS AS MEDICAL INSTRUMENTS... 

R. Haken, B. Bliimich 2000, (Anisotropy in tendon investigated in vivo by a portable NMR scanner, the NMR-MOUSE), J. Magn. Reson. 144, 195-199. 

The accurate calculation of the resonance frequencies of a tripod scanner is a complicated problem. The flexing modes are effectively coupled with the stretching modes. An evaluation of the lowest resonance frequency of the flexing mode provides an order-of-magnitude estimation of the lowest resonance frequency of the tripod scanner. For a piezo made of PZT-5A, 20 mm long and 2 mm thick, the radius of gyration is 2 mm/y/ 2 = 0.577 mm. The speed of sound is about 2.8 km/sec. Using Eq. (9.44), the resonance frequency is found to be 3.3 kHz, which is close to the values often observed experimentally. 

In this section, we describe the tube scanner, which has high piezo constants as well as high resonance frequencies. Moreover, it is much simpler than both the tripod scanners and bimorph-based scanners. The tube scanner soon became the predominant STM scanner after its invention by Binnig and Smith (1986). 

Once the tube scanner was invented (Binnig and Smith, 1986), it soon became the primary choice of piezo scanners in STM. Its small size and high natural resonance frequency make the mechanical design and vibration isolation much easier. Currently, most of the commercial STMs as well as home-made STMs use tube scanners. 

See Lead zirconate titanate ceramics Quality number 219 Quantum transmission 59 Reciprocal space 123, 353 Reciprocity principle 88 Reconstruction 14, 327 Au(lll) 327 DAS model 16 Si(lll)-2X1 14 Recursion relations 352 Repulsive atomic force 185, 192 Resonance frequency 234, 241 piezoelectric scanners 234 vibration isolation system 241 Resonance interactions 171, 177 and tunneling 177 Resonance theory of the chemical bond 172... 

NMR spectroscopy, commonly called magnetic resonance spectroscopy (MRS) in its in vivo application, is continuing to expand its reach in both biomedical research and clinical medicine. Currently, most in vivo MRS utilizes as a straightforward addition to MRI on a clinical scanner. The high sensitivity of permifs relatively small tissue volumes, on the order of 1-8 ml, to be probed in vivo in humans. With water suppression,... 

J. R. James, Y. Gao, V. C. Soon, S. M. Topper, A. Babsky and N. Bansal, Controlled radiofrequency hyperthermia using an MR scanner and simultaneous monitoring of temperature and therapy response by H, Na and P magnetic resonance spectroscopy in subcutaneously implanted 9L-gliosarcoma. Int.. Hyperthermia, 2010, 26, 79-90. 

The MRI (magnetic resonance imaging) body scanners used in hospitals operate with 400 MHz radiofrequency energy. How much energy does this correspond to in kilojoules per mole ... 

The modulation frequency is typically in the range from 100 Hz to 3 kHz, and thus much lower than the resonance frequencies of the cantilever and the scanner. This enables better control of the forces exerted on the sample. The z-mod-ulation amplitude can be varied between 10 nm and 1 pm to ensure that that the tip is retracted from the surface. Shear forces are reduced permitting investigation of soft samples because of the small duration of the tip-surface contact, between 10 3 and 10 4 s. Pulse force mode SFM has been used to map adhesion of heterogeneous polymers in dependence of temperature and molecular weight as well as map electrostatic double-layer interactions [158-160]. 

The quasi in situ SFM setup utilizes a modified commercial SFM (Dimension 3100 equipped with a NanoScope IV SPM controller and a XY closed-loop scanner, all from Veeco Instruments.). A detailed description of the setup is reported elsewhere [9,32,34], Si3N4 cantilevers from Olympus were used (OMCL-AC160TS, spring constant 40N/m, resonance frequency 200-300kHz). All measurements were performed at free amplitudes of about 30-50 nm and a relative set point of about 0.95. 

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