BioNMR
NMR aggregator & online community since 2003
BioNMR    
Learn or help to learn NMR - get free NMR books!
 

Go Back   BioNMR > NMR community > News from NMR blogs
Advanced Search
Home Forums Wiki NMR feeds Downloads Register Today's Posts



Jobs Groups Conferences Literature Pulse sequences Software forums Programs Sample preps Web resources BioNMR issues


Webservers
NMR processing:
MDD
NMR assignment:
Backbone:
Autoassign
MARS
UNIO Match
PINE
Side-chains:
UNIO ATNOS-Ascan
NOEs:
UNIO ATNOS-Candid
UNIO Candid
ASDP
Structure from NMR restraints:
Ab initio:
GeNMR
Cyana
XPLOR-NIH
ASDP
UNIO ATNOS-Candid
UNIO Candid
Fragment-based:
BMRB CS-Rosetta
Rosetta-NMR (Robetta)
Template-based:
GeNMR
I-TASSER
Refinement:
Amber
Structure from chemical shifts:
Fragment-based:
WeNMR CS-Rosetta
BMRB CS-Rosetta
Homology-based:
CS23D
Simshift
Torsion angles from chemical shifts:
Preditor
TALOS
Promega- Proline
Secondary structure from chemical shifts:
CSI (via RCI server)
TALOS
MICS caps, β-turns
d2D
PECAN
Flexibility from chemical shifts:
RCI
Interactions from chemical shifts:
HADDOCK
Chemical shifts re-referencing:
Shiftcor
UNIO Shiftinspector
LACS
CheckShift
RefDB
NMR model quality:
NOEs, other restraints:
PROSESS
PSVS
RPF scores
iCing
Chemical shifts:
PROSESS
CheShift2
Vasco
iCing
RDCs:
DC
Anisofit
Pseudocontact shifts:
Anisofit
Protein geomtery:
Resolution-by-Proxy
PROSESS
What-If
iCing
PSVS
MolProbity
SAVES2 or SAVES4
Vadar
Prosa
ProQ
MetaMQAPII
PSQS
Eval123D
STAN
Ramachandran Plot
Rampage
ERRAT
Verify_3D
Harmony
Quality Control Check
NMR spectrum prediction:
FANDAS
MestReS
V-NMR
Flexibility from structure:
Backbone S2
Methyl S2
B-factor
Molecular dynamics:
Gromacs
Amber
Antechamber
Chemical shifts prediction:
From structure:
Shiftx2
Sparta+
Camshift
CH3shift- Methyl
ArShift- Aromatic
ShiftS
Proshift
PPM
CheShift-2- Cα
From sequence:
Shifty
Camcoil
Poulsen_rc_CS
Disordered proteins:
MAXOCC
Format conversion & validation:
CCPN
From NMR-STAR 3.1
Validate NMR-STAR 3.1
NMR sample preparation:
Protein disorder:
DisMeta
Protein solubility:
camLILA
ccSOL
Camfold
camGroEL
Zyggregator
Isotope labeling:
UPLABEL
Solid-state NMR:
sedNMR


Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
  #1  
Old 11-21-2013, 01:14 AM
nmrlearner's Avatar
Senior Member
 
Join Date: Jan 2005
Posts: 23,714
Points: 193,617, Level: 100
Points: 193,617, Level: 100 Points: 193,617, Level: 100 Points: 193,617, Level: 100
Level up: 0%, 0 Points needed
Level up: 0% Level up: 0% Level up: 0%
Activity: 50.7%
Activity: 50.7% Activity: 50.7% Activity: 50.7%
Last Achievements
Award-Showcase
NMR Credits: 0
NMR Points: 193,617
Downloads: 0
Uploads: 0
Default Theoretical Aspects of Dynamic Nuclear Polarization in the Solid State: The Influence of High Radical Concentrations on the Solid Effect and Cross Effect Mechanisms

From The DNP-NMR Blog:

Theoretical Aspects of Dynamic Nuclear Polarization in the Solid State: The Influence of High Radical Concentrations on the Solid Effect and Cross Effect Mechanisms


Hovav, Y., et al., Theoretical Aspects of Dynamic Nuclear Polarization in the Solid State: The Influence of High Radical Concentrations on the Solid Effect and Cross Effect Mechanisms. Appl. Magn. Reson., 2012. 43(1-2): p. 21-41.


http://dx.doi.org/10.1007/s00723-012-0359-0


Dynamic nuclear polarization (DNP) is used to enhance signals in NMR and MRI experiments. During these experiments microwave (MW) irradiation mediates transfer of spin polarization from unpaired electrons to their neighboring nuclei. Solid state DNP is typically applied to samples containing high concentrations (i.e. 10–40 mM) of stable radicals that are dissolved in glass forming solvents together with molecules of interest. Three DNP mechanisms can be responsible for enhancing the NMR signals: the solid effect (SE), the cross effect (CE), and thermal mixing (TM). Recently, numerical simulations were performed to describe the SE and CE mechanisms in model systems composed of several nuclei and one or two electrons. It was shown that the presence of core nuclei, close to DNP active electrons, can result in a decrease of the nuclear polarization, due to broadening of the double quantum (DQ) and zero quantum (ZQ) spectra. In this publication we consider samples with high radical concentrations, exhibiting broad inhomogeneous EPR line-shapes and slow electron cross-relaxation rates, where the TM mechanism is not the main source for the signal enhancements. In this case most of the electrons in the sample are not affected by the MW field applied at a discrete frequency. Numerical simulations are performed on spin systems composed of several electrons and nuclei in an effort to examine the role of the DNP inactive electrons. Here we show that these electrons also broaden the DQ and ZQ spectra, but that they hardly cause any loss to the DNP enhanced nuclear polarization due to their spin-lattice relaxation mechanism. Their presence can also prevent some of the polarization losses due to the core nuclei.


Go to The DNP-NMR Blog for more info.
Reply With Quote


Did you find this post helpful? Yes | No

Reply
Similar Threads
Thread Thread Starter Forum Replies Last Post
Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics
From The DNP-NMR Blog: Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics Franck, J.M., et al., Quantitative cw Overhauser effect dynamic nuclear polarization for the analysis of local water dynamics. Prog Nucl Magn Reson Spectrosc, 2013. 74(0): p. 33-56. http://www.ncbi.nlm.nih.gov/pubmed/24083461
nmrlearner News from NMR blogs 0 11-21-2013 01:14 AM
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State
From The DNP-NMR Blog: Dynamic Nuclear Polarization Enhanced NMR in the Solid-State Akbey, Ü., et al., Dynamic Nuclear Polarization Enhanced NMR in the Solid-State. 2013, Springer Berlin Heidelberg. p. 1-48. http://dx.doi.org/10.1007/128_2013_436
nmrlearner News from NMR blogs 0 08-26-2013 08:46 PM
[NMR paper] Dynamic Nuclear Polarization Enhanced NMR in the Solid-State.
Dynamic Nuclear Polarization Enhanced NMR in the Solid-State. Dynamic Nuclear Polarization Enhanced NMR in the Solid-State. Top Curr Chem. 2013 Jul 7; Authors: Akbey U, Franks WT, Linden A, Rydmark MO, Lange S, Oschkinat H Abstract Nuclear magnetic resonance (NMR) spectroscopy is one of the most commonly used spectroscopic techniques to obtain information on the structure and dynamics of biological and chemical materials. A variety of samples can be studied including solutions, crystalline solids, powders and hydrated protein...
nmrlearner Journal club 0 07-09-2013 02:47 PM
The interplay between the solid effect and the cross effect mechanisms in solid state 13C DNP at 95 GHz using trityl radicals
From The DNP-NMR Blog: The interplay between the solid effect and the cross effect mechanisms in solid state 13C DNP at 95 GHz using trityl radicals Banerjee, D., et al., The interplay between the solid effect and the cross effect mechanisms in solid state 13C DNP at 95 GHz using trityl radicals. J. Magn. Reson., 2013. 230(0): p. 212-219. http://dx.doi.org/10.1016/j.jmr.2013.02.010
nmrlearner News from NMR blogs 0 05-07-2013 12:31 AM
High-Field (13)C Dynamic Nuclear Polarization with a Radical Mixture
From the The DNP-NMR Blog: High-Field (13)C Dynamic Nuclear Polarization with a Radical Mixture Michaelis, V.K., et al., High-Field (13)C Dynamic Nuclear Polarization with a Radical Mixture. J Am Chem Soc, 2013. http://www.ncbi.nlm.nih.gov/pubmed/23373472
nmrlearner News from NMR blogs 0 04-15-2013 08:52 AM
Dual-band Selective Double Cross Polarization for Heteronuclear Polarization Transfer between Dilute Spins in Solid-State MAS NMR
Dual-band Selective Double Cross Polarization for Heteronuclear Polarization Transfer between Dilute Spins in Solid-State MAS NMR Publication year: 2012 Source:Journal of Magnetic Resonance</br> Zhengfeng Zhang, Yimin Miao, Xiaoli Liu, Jun Yang, Conggang Li, Feng Deng, Riqiang Fu</br> A sinusoidal modulation scheme is described for selective heteronuclear polarization transfer between two dilute spins in double cross polarization magic-angle-spinning nuclear magnetic resonance spectroscopy. During the second N->C cross polarization, the 13C RF amplitude is...
nmrlearner Journal club 0 03-09-2012 09:16 AM
Dual-band Selective Double Cross Polarization for Heteronuclear Polarization Transfer between Dilute Spins in Solid-State MAS NMR
Dual-band Selective Double Cross Polarization for Heteronuclear Polarization Transfer between Dilute Spins in Solid-State MAS NMR Publication year: 2012 Source: Journal of Magnetic Resonance, Available online 5 March 2012</br> Zhengfeng*Zhang, Yimin*Miao, Xiaoli*Liu, Jun*Yang, Conggang*Li, ...</br> A sinusoidal modulation scheme is described for selective heteronuclear polarization transfer between two dilute spins in double cross polarization magic-angle-spinning nuclear magnetic resonance spectroscopy. During the second N->C cross polarization, theC RF amplitude is modulated...
nmrlearner Journal club 0 03-06-2012 06:04 AM
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR.
Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR. Related Articles Dynamic nuclear polarization experiments at 14.1 T for solid-state NMR. Phys Chem Chem Phys. 2010 Jun 14;12(22):5799-803 Authors: Matsuki Y, Takahashi H, Ueda K, Idehara T, Ogawa I, Toda M, Akutsu H, Fujiwara T Instrumentation for high-field dynamic nuclear polarization (DNP) at 14.1 T was developed to enhance the nuclear polarization for NMR of solids. The gyrotron generated 394.5 GHz submillimeter (sub-mm) wave with a power of 40 W in the second harmonic...
nmrlearner Journal club 0 08-26-2010 04:41 PM



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



BioNMR advertisements to pay for website hosting and domain registration. Nobody does it for us.



Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright, BioNMR.com, 2003-2013
Search Engine Friendly URLs by vBSEO 3.6.0

All times are GMT. The time now is 11:14 PM.


Map