The influences of polymerization parameters such as polymerization temperature, Al/Ni Wnt inhibitor molar ratio, reaction time, and catalyst concentration on catalytic activity and molecular weight of the polystyrene were investigated in detail. The influence of the bulkiness of the substituents on polymerization activity was also studied. All of the four catalytic systems exhibited high activity (up to 10.50 x 10(5) gPS/(mol Ni h)) for styrene polymerization and provide polystyrene with moderate to low molecular weights (M-w = 4.76 x 10(4)-0.71 x 10(4) g/mol) and narrower molecular weight distributions about 2. The obtained polystyrene was characterized by means of FTIR, H-1-NMR, and C-13-NMR techniques. The results
indicated that the polystyrene was atactic polymer. The analysis of the end groups of polystyrene indicated that styrene polymerization with bispyrazolylimine dinickel complexes/MAO catalytic systems proceeded through a coordination mechanism. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 545-550, 2011″
“The effects of an electric field on the magneto-dynamics of a FeGaB/PZN-PT (lead JQ-EZ-05 mw zinc niobate-lead titanate) multiferroic heterostructure were investigated. It was found that with the increase of electric field applied on the PZN-PT
layer, the magnetoelectric coupling is increased, and the magnetization of the FeGaB film changes gradually from an unpinned to a pinned boundary condition at the FeGaB/PZN-PT interface. This change leads to the observation of the first-order standing spin wave mode and the varied resonance intensity ratio between the standing mode and the uniform mode from 1 to 5% in the FMR spectra. The E-field induced surface anisotropy change confirms the strain mediated magnetoelectric mechanism through the interface between multiferroic heterostructures. (c) 2011 American Institute of Physics. [doi: 10.1063/1.3562975]“
“With the aim
of assessing whether Selleckchem Galardin the Bath Ankylosing Spondylitis Activity and Function Indices (BASDAI and BASFI) are reliable measures of disease activity and function in patients with spondyloarthritides (SpAs), 341 patients with SpA (representing ankylosing spondylitis (14.5%), psoriatic arthritis (27.3%), enteropathic arthritis (6.3%), reactive arthritis (4.9%), and undifferentiated arthritis (46.5%) were asked to complete the BASDAI and BASFI. They were asked to report what their main problems associated with the disease were from a list of seven symptoms: fatigue, neck pain, upper back pain, lower back pain, stiffness, joint pain or swelling, and pain with pressure on joints. Correlations between the main symptoms experienced by patients with SpAs and the indices, defined by Spearman’s correlation coefficient, showed that BASDAI best correlated with neck pain [BASDAI 2 and total BASDAI score correlate strongly (p = 0.003 and 0.001, respectively), and BASDAI 1, 4, and 5 correlate moderately (p = 0.