FF-domains have been found widely in many signaling proteins. In this paper, the structure characteristics of FF-domain of the formin-binding protein 11 (FBP11) were studied by NMR spectroscopy. The spin systems for most of the amino acid residues in the FF-domain were identified by analyzing NMR spectra acquired in H₂O and D₂O. Sequence specific assignment of the spin systems was made using d_αN, d_NN and d_βN NOEs correlation calculated from NOESY spectra. The secondary structure of the FF-domain was found to include three α helices.

Based on the Peripheral Component Interconnect (PCI) bus of a personal computer, a highly integrated gradient waveform generator used for nuclear magnetic resonance and magnetic resonance imaging was developed. Three independent gradient waveform channels on a printed circuit board were used as the sources for X, Y and Z gradients. The main feature of the design is utilization of field programmable gate array technology, making the hardware structure simpler and more flexible. In addition, digital preemphasis function was integrated in the gradient waveform generator and implemented in the field programmable gate array.

³¹P NMR spectra of some organic pesticides were acquired at 600 MHz and analyzed. The effects of factors such as complex coupling, interconvert isomer, suffocate spin and chiral carbon on the appearance of the spectra were studied and discussed in the paper.

Phencyclonate {2′-pheny-2′-cycloamyl-2′-hydroxyacetic-N-methly-3-azabiclo[3, 3, 1] nonane-9a-carboxylate} was synthesized and studied by 1D-HOHAHA and 1D-NOESY NMR spectroscopy employing frequency-selective radiofrequency pulses and pulsed field gradients. The results showed that all protons in the compound could be assigned by the combined use of the two techniques. Based on the results obtained from the 1D-NOESY experiment, the conformational property and C-9 configuration were elucidated as (1A).

A pair of stereoisomeric furostanol saponins were isolated from fresh rhizomes of Polygonatum kingianum, and identified as 26-O-β-D-glucopyranosyl 25(S)-furostane-5-en-3β, 22, 26-triol-12-on-3-O-β-D-glucopyranosyl (1→4)-β-D-fucopyranoside (1) and 26-O-β-D-glucopyranosyl 25(R)-furostane-5-en-3β, 22, 26-triol-12-on-3-O-β-D-glucopyranosyl (1→4)-β-D- fucopyranoside (2), respectively, by 1D ¹H and ¹³C NMR and 2D NMR (including ¹H-¹H COSY, HSQC and HMBC). ¹H and ¹³C chemical shifts of the two compounds were completely assigned, and the configurations of the methyl group at C-25 were determined.

Studying the composition of product of thermally dissolved coaloil slurry can provide important information on how to control direct coal liquefaction. In this study, Shenhua coal was thermally dissolved in an autoclave using different solvents at different temperatures (250~370 ℃). Solid state ¹³C CP/MAS/TOSS NMR spectroscopy was used to analyze Shenhua coal, its thermally dissolved products and extracted residue. The results showed that thermal extraction removed oxygen-containing functional groups and some aliphatic hydrocarbon in the Shenhua coal, and fractured a fraction of aromatic bridgehead carbons and nonprotonated carbons. Increasing reaction temperature and continuous supply of hydrogen decreased the aromaticity of the THF extract, but increased the extraction yield.

²⁹Si and ²⁷Al MAS NMR spectra of calcined kaolin coming from different regions and kaolin calcined at different temperatures were acquired and compared. The results showed that the ²⁹Si spectra of calcined kaolin coming from different regions were similar while the ²⁷Al spectra were different. Calcination temperature was found to influence the ²⁹Si and ²⁷Al spectra of calcined kaolin obtained from the same area.

An equation: δ_cal=253.0+Δα+Δβ+Δγ for calculating ¹⁷O chemical shifts of carboxylic groups in carboxylic acids was provided. 17 substituent parameters in the equation were obtained with leastsquare linear regression. Experimentally measured ¹⁷O chemical shifts from 42 carboxylic acids were used as the test set to examine the accuracy of the calculated results. The confidence limit was found to be 99.5% and the calculating errors for about 95% of the compounds were less than 5.0 (relative errors ≤0.5%).

In this study, 338 equivalence resonance carbon atoms in 54 pyranoses were characterized by the two dimensional topological structure of the molecules and the atomic elementary electronegativity interaction vector (AEIV). Three-parameter multiple linear regression was used to simulate ¹³C chemical shifts of these atoms. Correlation coefficient R_cum of the model was 0.969 6. Leave-one-out cross-validation was used to verify the predictive abilities of this model, and the correlation coefficient Q_cum was found to be 0.968 6.

Carbon-13 chemical shifts of 155 carbonyl groups were measured from 155 carbonyl compounds. The relationships between the ¹³C chemical shifts and the molecular distance-edge vector (MDE) and the γ parameter of the compounds were studied. The results indicated that the ¹³C chemical shifts of carbonyl compounds could be calculated by following equation:

δ_C=a+bμ₅₁+cμ₅₂+dμ₅₃+eμ₅₄+fγ.

The paper reports measurements of T₁ relaxation time and its distribution in porous media. Three models: the single-exponential model, the double-exponential model, and the multi-exponential model (τ -distribution curves) were used to fit the experimental data and compared for their performance. The Levenberg-Marquardt algorithm was used to perform nonlinear regression.

It was found in this study that the ESR spectra of three nitroxide radicals, 4-hydroxy-2,2,6,6-tetramethyliperidine-1-oxyl (R₁), 4-azido-2,2,6,6-tetramethyliperdine-1-oxyl (R₂) and 4-oxybenzene-sulfonyl-2,2,6,6-tetramethyliperidene-1-oxyl (R₃), show distinctive changes in rotational correlation time τ_C and hyperfine splitting constants a_N when included in β-cyclodextrin (β-CD) and 2-hydroxypropyl-β-CD in aqueous solution. Based on the EPR results, it is suggested that the steric factors and polarity of the functional groups affect the inclusion reaction.

Taking account of the effects of local distorted structure of the doped crystal, the relationship between the local distorted structure and the EPR parameters was established for RbMgF₃: Ni²⁺ system. The zero-field splitting parameter D and the g factors for Ni²⁺ ions in RbMgF₃ crystals with C_3v and D_3d symmetry were calculated, and found to agree well with the experimentally measured values.

The definition of metabonomics as “the quantitative measurement of the dynamic multi-parametric metabolic response of living systems to pathophysiological stimuli or genetic modification”is now becoming widely known. Here the role that metabonomics has in modern systems biology is reviewed and the techniques used are summarised.  This article concentrates on NMR spectroscopic methods but the use of mass spectrometry is increasing, and this is usually prefaced by a separations step using HPLC. Some modern developments in NMR technology are having an impact on metabonomics and these are also described. Finally, some recent applications of metabonomics are summarised including an improved understanding of normal physiological variation, the adverse effects of drugs and other xenobiotics, the impact of xenobiotic substances in environment pollution and the increasing use of metabonomics as a method for disease diagnosis.

Chemically induced dynamic electron polarization (CIDEP) is a powerful tool to determine and characterize intermediate paramagnetic species. It plays especially important roles in studying the mechanisms of transient photochemical and photophysical processes. In this review, four basic theories for CIDEP were introduced, and the polarized conditions required to obtain different experimental CIDEP spectra were discussed. Recent progresses in CIDEP studies of photochemical process in the homogeneous solvents and microheterogeneous phase systems were also presented.

Well-logging and mud-logging using nuclear magnetic resonance (NMR) technology are based on evaluation and interpretation of T₂ spectrum measured from the rock samples excavated from potential oil wells. Many factors may affect the T₂ spectrum of the rock samples, including technical parameters used in measurement, physical/chemical properties of the rock samples (i.e., lithology, particle size, granularity, dry or wet, composite and properties of pore-fluid, magnetic susceptibility, wettability and so on), degree of mineralization of formation water etc. The most important parameter relevant to logging that is obtainable from the T₂ spectra is the T₂ cutoff value, whose accurate determination influences greatly the meaning of the results of NMR measurements. In this paper, we reviewed the factors affecting T₂ spectra of oil well samples and the current methods for determining T₂ cutoff value.