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Doty "XC" MAS
Probes
Low E Field Sample Coils Since 1997
Reliable,
High-field MAS Probes for Solids, Tissues, and Liquids - for use in
WB or NB
High
Performance
13C-1H MAS-J-HMQC Solid State NMR Spectrum of β-maltose,
taken at
natural abundance in 13C . Homonuclear 1H
decoupling in the J evolution periods, τ , and t1 was
achieved using the PMLG technique.
See: Yates, et al., JACS . 2005, 127, 10216-10220. Spectrum
courtesy of S.P. Brown, Univ. of Warwick, UK.
High
Performance, Low Decoupler Heating |
110 kHz decoupling fields at 750 MHz
with 10 to 25 times lower sample heating compared to solenoid-only
probes. Stable tuning, low heating,
high sensitivity, and excellent B1 matching on both
coils, even for lossy samples. Unlike many sample coil designs,
the B1 homogeneity
of the XC coil is not significantly effected by the sample because
of its inherent electrical balance, symmetry, and very low inductance.
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XC
MAS probe features:
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Highest
decoupling efficiency, over 110 kHz for XC4 NB at 750 MHz with
250 W.
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An order of magnitude
lower decoupler heating of biological solids.
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High
rf homogeneity and efficiency on all channels.
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High
sensitivity, ≈ 250:1 on 70 μg glycine
at 750 MHz (triple-resonance XC4, nt=4, as
seen in figure
2 on this page).
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Lowest
thermal gradients (<1°C over sample
with full 1H decoupling, 13
kHz MAS, in XC5 with a silicon nitride
stator).
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Minimal 1H, 27Al, 13C
(CP) background. Special background
minimizations may affect some features such as VT range
and maximum B1 , B2 ,
B3 , B4 .
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Longest
acquisition times at full decoupling, 150-300
ms.
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Simple,
low-cost, leak-proof, Kel-F MAS
sample cells (also
known as sealing cells)
for liquids, CC, and
tissues.
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Standard
VT ranges: -80°C to +120°C for narrow-bore, -140°C
to +170°C for wide-bore. Extended temperature range
is available. Extended WB HT ranges to 250°C
(or
750°C HT Probe).
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Excellent B0 lineshape,
0.003 ppm FWHM.
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Optical
spin rate detection.
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CRAMPS,
wideline, slow-MAS, and fast-MAS solids.
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Suitable
for conventional solids or liquids and inverse
detection techniques.
Must remove probe to change samples.
Note:
Not all features are available on every probe
Sealing
Cells for use inside thin
and thick walled ceramic rotors
with
short plastic turbine caps.
MAS
at High Fields
Spectra courtesy of NIMS, Japan
VAS
and SAS Options
VAS
(Variable Angle Spinning, 0° to 90°, manual control) and SAS
(Switched Angle Spinning, 0° to 90° , with servo/computer
control) are now available only on the widebore XC MAS probe. Expect
more updates
here
in the near future. Performance
of a single HF ( 1H or 19F) cross-coil is essentially
independent of the spinner angle, although when two HF channels are
present, HF efficiency at 90° is about half that at 0° . An
XC probe can be ordered with a 4 mm, 5 mm, or 7 mm spinner.
For
information on our new SAS Probe…
Additional
XC Probe Specifications...
Please
contact sales
with questions or quote requests.
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